document_title: The Big Sick

question_text: who plays the mom in the big sick

question_tokens: who plays the mom in the big sick

text: The Big Sick

text: Plot[edit]

text: Kumail is a comedian in Chicago trying to get his big break performing standup as well as a self-produced one-man show about his Pakistani background. His Muslim immigrant parents frequently set him up with young Pakistani women, expecting that he will follow their example of an arranged marriage; he is uninterested but tolerates the introductions. He also lets them believe he still shares their religious faith, though he has become agnostic.

text: During a standup show, Kumail is heckled by Emily, a white woman in the audience. He approaches her after the show and their one-night stand develops into a on-going relationship. Kumail does not tell his family about Emily, as they would disapprove, and his relationship with Emily is strained as he holds back, fearful of losing his family who disowned one of his cousins after he married a white woman. Emily finds pictures of the women Kumail's parents have set him up with; they argue and she asks whether he sees a long-term future with her, given his family's expectations. When he says he doesn't know, Emily ends their relationship.

text: Kumail learns weeks later that Emily has been taken to the hospital after having fainted. A doctor tells him that Emily has a serious lung infection and must be immediately placed in an induced coma with tracheal intubation. He signs the permission form and calls her parents, Beth and Terry. Aware of their daughter's messy breakup with Kumail, they tell him he is not needed, but Kumail stays and the three become close as they deal with Emily's illness.

text: Surgery is ineffective and the infection spreads to Emily's kidneys. Beth wants to transfer Emily to a different hospital, but Kumail and Terry disagree. Beth and Terry argue, and she brings up Terry's past. Terry stays at Kumail’s apartment where he reveals that he cheated on Beth and regrets it.

text: Kumail's parents visit his apartment, angry that he is not taking their marriage suggestions seriously. Kumail tells them that he does not want an arranged marriage and no longer practices Islam, and reveals his relationship with Emily. His parents disown him.

text: Moments before an audition for the Montreal Comedy Festival, Kumail learns that the infection has reached Emily's heart. Distraught on stage, Kumail spends the audition tearfully recounting his fears about Emily’s health, and fails the audition.

text: Emily wakes from her coma. The doctors explain she has adult-onset Still's disease, a rare and serious but treatable illness; Kumail inadvertently helped them diagnose her when he mentioned she had an ankle injury that was slow to heal. Still pained from their breakup, Emily tells Kumail to leave. Neverthless, Beth invites Kumail to Emily's homecoming party. Kumail asks Emily to take him back, but she refuses, reminding him that while he may have had a transformative experience during her illness, she was unconscious for duration and for her nothing had changed.

text: Kumail decides to move to New York City with two comedian friends. He tells his family about his plans and refuses to allow them to reject him. Emily discovers a video of Kumail's disastrous audition in which he spoke openly about his feelings for her and she goes to find him after his one-man show, saying she has something to tell him. But before she can, he tells her he is moving to New York City. He asks what she had wanted to tell him and she says only that she appreciates everything he did for her while she was in a coma and wishes him well in New York.

text: As Kumail prepares to depart for New York, his parents visit. His father tells him they are still angry, but gives him a dish of his favorite food and ask him to stay in touch. The film ends with Kumail performing in New York, where he is heckled by someone in the crowd; he sees that it is Emily.

text: Cast[edit]

text:
Kumail Nanjiani as Kumail
Zoe Kazan as Emily Gardner (based on Emily V. Gordon), Beth and Terry’s daughter
Holly Hunter as Beth Gardner, Emily’s mother and Terry’s wife
Ray Romano as Terry Gardner, Emily’s father and Beth’s husband
Bo Burnham as CJ
Zenobia Shroff as Sharmeen
Anupam Kher as Azmat
Adeel Akhtar as Naveed
Aidy Bryant as Mary
Rebecca Naomi Jones as Jessie
Kurt Braunohler as Chris
Shenaz Treasury as Fatima
David Alan Grier as Andy Dodd
Vella Lovell as Khadija
Linda Emond as Dr. Cunningham

text: Production[edit]

text: In December 2015, it was announced Kumail Nanjiani would star in the film from a screenplay written by him and wife Emily V. Gordon, while Judd Apatow would produce alongside Barry Mendel, under their Apatow Productions banner, while FilmNation Entertainment would finance the film.[6] Michael Andrews composed the film's score.[7]

text: Casting[edit]

text: In February 2016, Zoe Kazan joined the cast,[8] along with Holly Hunter and Ray Romano in April 2016.[9] Unlike many of the other portrayals in The Big Sick, Romano's and Hunter's roles in the film were not modeled after Emily V. Gordon's actual parents. Instead, Hunter said that she never contacted or spoke with Gordon's mother before playing the part, as she wanted to "feel my own freedom with the character".[10] In May 2016, Aidy Bryant, Bo Burnham, Adeel Akhtar and Kurt Braunohler also joined the cast of the film.[11][12] David Alan Grier was cast in The Big Sick after he met with Emily V. Gordon when she was a writer for The Carmichael Show. Grier's role was part of a larger subplot that was ultimately cut from the film's release.[13][14]

text: Anupam Kher's casting in the film was reported in June 2016. He was directly contacted by Kumail Nanjiani himself, as Nanjiani's own father had recommended Kher play the role. According to Kher himself, his character's last scene in the film was the first scene he had filmed for the production. The Big Sick marks Kher's 500th appearance in a feature film.[15][16][17][18]

text: Writing[edit]

text: The screenplay for The Big Sick is written by Emily V. Gordon and her husband Kumail Nanjiani and is loosely based on the real-life courtship between them before their marriage in 2007. According to Nanjiani, the idea to make a script about them was first inspired by the film's eventual co-producer Judd Apatow when the two met while appearing in a 2012 episode of the You Made It Weird podcast.[19] Developed over the course of three years, the script has been called semi-autobiographical because, in addition to the two lead characters modeled after them, many of the events occurring during Gordon and Nanjiani's relationship are noted as being portrayed to an extent in the film.[20][21][22][23][24]

text: Though not part of the original script, a real-life incident involving Holly Hunter heckling an unnamed player during a US Open tennis match inspired a similar scene in the film where Nanjiani's character is heckled during one of his stand-up sets.[25]

text: Filming[edit]

text: Principal photography began on May 11, 2016.[26]

text: Release[edit]

text: The Big Sick premiered at the Sundance Film Festival on January 20, 2017.[27] Shortly after, Amazon Studios acquired distribution rights to the film, after bids from Sony Pictures and Fox Searchlight Pictures.[28] The $12 million acquisition marked the second-largest deal of the 2017 festival.[29][30] Lionsgate partnered with Amazon on the U.S. release, and spent around $20 million on marketing the film.[31][32] It also screened at South by Southwest on March 16, 2017, where it won an Audience Award in the category Festival Favorites.[33] The film began a limited release on June 23, 2017, before going wide on July 14, 2017.[34]

text: Box office[edit]

text: The Big Sick grossed $42.9 million in the United States and Canada, and $13.4 million in other territories, for a total gross of $56.2 million.[3]

text: In the film's limited opening weekend, it made $421,577 from five theaters (a per-theater gross of $84,315, the best of 2017 until Lady Bird in November), finishing 17th at the box office.[35] The film expanded to 2,597 theaters on July 14, 2017, and was projected to gross $9–11 million over the weekend.[32] It grossed $7.6 million over the weekend, finishing fifth at the box office.[36] On July 25, the film crossed $26 million, becoming the second highest-grossing independent film of 2017.[37][38]

text: Critical response[edit]

text: On review aggregator Rotten Tomatoes, the film holds an approval rating of 98% based on 252 reviews, with an average rating of 8.2/10. The site's critical consensus reads, "Funny, heartfelt, and intelligent, The Big Sick uses its appealing leads and cross-cultural themes to prove the standard romcom formula still has some fresh angles left to explore."[39] It was rated as Rotten Tomatoes' #1 summer movie of 2017.[40] On Metacritic, which assigns a normalized rating to reviews, the film received an average score of 86 out of 100, based on 47 critics, indicating "universal acclaim."[41] Audiences polled by CinemaScore gave the film an average grade of "A" on an A+ to F scale.[36] According to a poll conducted by AwardsDaily in July 2017, polling one hundred critics, The Big Sick was voted the second best film of 2017 so far, behind Get Out.[42]

text: In a review for the Toronto Star, Peter Howell gave The Big Sick four stars out of four, praising the film as "hilarious and heartbreaking", as well as applauding the performances of the entire cast.[43] Richard Roeper similarly gave the film four stars out of four in his review for the Chicago Sun-Times, labeling it as "without a doubt one of the best romantic comedies I have seen in a long time."[44] The Big Sick was also selected as an "NYT Critic's Pick" by Manohla Dargis of The New York Times. In her review, Dargis praised Michael Showalter's direction and the screenplay by Emily V. Gordon and Kumail Nanjiani for "revitalizing an often moribund subgenre with a true story of love, death and the everyday comedy of being a 21st-century American.[45]

text: While praising the lead performances of Nanjiani, Kazan and Romano, Robbie Collin of The Daily Telegraph wrote a mixed review for The Big Sick. Collin contends that director Showalter "never comes close to dampening down its leading couple's inextinguishable appeal."[46] In a negative review for The New Yorker, Richard Brody wrote that the film "suffers from an excess of pleasantness, and this very pleasantness thins out its substance, blands out its tone, weakens its comedy."[47]

text: Accolades[edit]

text:
Award
Date of ceremony
Category
Recipient(s) and nominee(s)
Result
Ref.

AARP's Movies for Grownups Awards
February 5, 2018
Best Supporting Actress
Holly Hunter
Nominated
[48][49][50]

Best Intergenerational Film
The Big Sick
Nominated

Academy Awards
March 4, 2018
Best Original Screenplay
Emily V. Gordon and Kumail Nanjiani
Nominated
[51]

American Film Institute
January 5, 2018
Top Ten Films of the Year
The Big Sick
Won
[52]

Austin Film Critics Association
January 8, 2018
Best Supporting Actress
Holly Hunter
Nominated
[53]

Best Original Screenplay
Emily V. Gordon and Kumail Nanjiani
Nominated

Top 10 Films
The Big Sick
9th Place

Cinema For Peace
February 19, 2018
Most Valuable Movie of the Year
The Big Sick
Nominated
[54]

Chicago Film Critics Association
December 12, 2017
Best Supporting Actress
Holly Hunter
Nominated
[55]
[56]

Best Original Screenplay
Emily V. Gordon and Kumail Nanjiani
Nominated

Critics' Choice Movie Awards
January 11, 2018
Best Picture
The Big Sick
Nominated
[57]

Best Supporting Actress
Holly Hunter
Nominated

Best Original Screenplay
Emily V. Gordon and Kumail Nanjiani
Nominated

Best Comedy
The Big Sick
Won

Best Actor in a Comedy
Kumail Nanjiani
Nominated

Best Actress in a Comedy
Zoe Kazan
Nominated

Dallas–Fort Worth Film Critics Association
December 13, 2017
Best Supporting Actress
Holly Hunter
4th Place
[58]

Detroit Film Critics Society
December 7, 2017
Best Screenplay
Emily V. Gordon and Kumail Nanjiani
Nominated
[59]

Best Supporting Actress
Holly Hunter
Nominated

Best Ensemble
The cast of The Big Sick
Nominated

Empire Awards
March 18, 2018
Best Comedy
The Big Sick
Pending
[60]
[61]

Florida Film Critics Circle
December 23, 2017
Best Supporting Actress
Holly Hunter
Nominated
[62]
[63]

Best Original Screenplay
Emily V. Gordon and Kumail Nanjiani
Nominated

Best Cast
The cast of The Big Sick
Nominated

Georgia Film Critics Association
January 12, 2018
Best Picture
The Big Sick
Nominated
[64]

Best Supporting Actress
Holly Hunter
Nominated

Best Original Screenplay
Emily V. Gordon and Kumail Nanjiani
Nominated

Golden Tomato Awards
January 3, 2018
Best Wide Release 2017
The Big Sick
2nd Place
[65]

Best Romance Movie 2017
The Big Sick
Won

Gotham Awards
November 27, 2017
Best Screenplay
Emily V. Gordon and Kumail Nanjiani
Nominated
[66]

Houston Film Critics Society
January 6, 2018
Best Picture
The Big Sick
Nominated
[67]

Best Supporting Actress
Holly Hunter
Nominated

Best Screenplay
Emily V. Gordon and Kumail Nanjiani
Nominated

Humanitas Prize
February 16, 2018
Feature – Comedy
Emily V. Gordon and Kumail Nanjiani
Pending
[68]

IGN Awards
December 19, 2017
Movie of the Year
The Big Sick
Nominated
[69]

Best Comedy Movie
The Big Sick
Runner-up

Best Lead Performer in a Movie
Kumail Nanjiani
Nominated

Best Supporting Performer in a Movie
Holly Hunter
Nominated

Ray Romano
Nominated

Independent Spirit Awards
March 3, 2018
Best Supporting Female
Holly Hunter
Nominated
[70]

Best First Screenplay
Emily V. Gordon and Kumail Nanjiani
Won

IndieWire Critics Poll
December 19, 2017
Best Supporting Actress
Holly Hunter
4th Place
[71]

London Film Critics' Circle
January 28, 2018
Supporting Actress of the Year
Holly Hunter
Nominated
[72]

Make-Up Artists and Hair Stylists Guild
February 24, 2018
Feature Motion Picture: Best Contemporary Makeup
Kirsten Sylvester and Leo Won
Nominated
[73]

Feature Motion Picture: Best Contemporary Hair Styling
Tonia Ciccone and Toni Roman-grimm
Nominated

Online Film Critics Society
December 28, 2017
Best Supporting Actress
Holly Hunter
Nominated
[74]

Palm Springs International Film Festival
January 2, 2018
Career Achievement Award
Holly Hunter
Won
[75]

Producers Guild of America
January 20, 2018
Best Theatrical Motion Picture
Judd Apatow and Barry Mendel
Nominated
[76]

San Diego Film Critics Society
December 11, 2017
Best Supporting Actress
Holly Hunter
Nominated
[77]
[78]

Best Original Screenplay
Emily V. Gordon and Kumail Nanjiani
Nominated

Best Comedic Performance
Ray Romano
Nominated

San Francisco Film Critics Circle
December 10, 2017
Best Supporting Actress
Holly Hunter
Nominated
[79]

Best Original Screenplay
Emily V. Gordon and Kumail Nanjiani
Nominated

Santa Barbara International Film Festival
January 31, 2018
Virtuoso Award
Kumail Nanjiani
Won
[80]

Satellite Awards
February 10, 2018
Best Film
The Big Sick
Nominated
[81]

Best Supporting Actress
Holly Hunter
Nominated

Screen Actors Guild Awards
January 21, 2018
Outstanding Performance by a Cast in a Motion Picture
The cast of The Big Sick
Nominated
[82]

Outstanding Performance by a Female Actor in a Supporting Role
Holly Hunter
Nominated

Seattle Film Critics Society
December 18, 2017
Best Supporting Actress
Holly Hunter
Nominated
[83]

Best Screenplay
Emily V. Gordon and Kumail Nanjiani
Nominated

South by Southwest
March 18, 2017
Audience Award: Festival Favorites
The Big Sick
Won
[84]

St. Louis Film Critics Association
December 17, 2017
Best Supporting Actress
Holly Hunter
Runner-up
[85]

Best Original Screenplay
Emily V. Gordon and Kumail Nanjiani
Nominated

Washington D.C. Area Film Critics Association
December 8, 2017
Best Supporting Actress
Holly Hunter
Nominated
[86]

Best Original Screenplay
Emily V. Gordon and Kumail Nanjiani
Nominated

Women Film Critics Circle
December 17, 2017
Best Screen Couple
The Big Sick
Won
[87]
[88]

Writers Guild of America
February 11, 2018
Best Original Screenplay
Emily V. Gordon and Kumail Nanjiani
Nominated
[89]


document_title: Ozone depletion

question_text: ozone layer depletion in antartica is due to which compound

question_tokens: ozone layer depletion in antartica is due to which compound

root

text: Ozone depletion

text: Ozone cycle overview[edit]

text:
Three forms (or allotropes) of oxygen are involved in the ozone-oxygen cycle: oxygen atoms (O or atomic oxygen), oxygen gas (O
2 or diatomic oxygen), and ozone gas (O
3 or triatomic oxygen). Ozone is formed in the stratosphere when oxygen molecules photodissociate after intaking ultraviolet photons. This converts a single O
2 into two atomic oxygen radicals. The atomic oxygen radicals then combine with separate O
2 molecules to create two O
3 molecules. These ozone molecules absorb ultraviolet (UV) light, following which ozone splits into a molecule of O
2 and an oxygen atom. The oxygen atom then joins up with an oxygen molecule to regenerate ozone. This is a continuing process that terminates when an oxygen atom recombines with an ozone molecule to make two O
2 molecules.

tag: p

text:
O + O
3 → 2 O
2

text: The total amount of ozone in the stratosphere is determined by a balance between photochemical production and recombination.

text: Ozone can be destroyed by a number of free radical catalysts; the most important are the hydroxyl radical (OH·), nitric oxide radical (NO·), chlorine radical (Cl·) and bromine radical (Br·). The dot is a notation to indicate that each species has an unpaired electron and is thus extremely reactive. All of these have both natural and man-made sources; at the present time, most of the OH· and NO· in the stratosphere is naturally occurring, but human activity has drastically increased the levels of chlorine and bromine. These elements are found in stable organic compounds, especially chlorofluorocarbons, which can travel to the stratosphere without being destroyed in the troposphere due to their low reactivity. Once in the stratosphere, the Cl and Br atoms are released from the parent compounds by the action of ultraviolet light, e.g.

text:
CFCl
3 + electromagnetic radiation → Cl· + ·CFCl
2

text:
Ozone is a highly reactive molecule that easily reduces to the more stable oxygen form with the assistance of a catalyst. Cl and Br atoms destroy ozone molecules through a variety of catalytic cycles. In the simplest example of such a cycle,[5] a chlorine atom reacts with an ozone molecule (O
3), taking an oxygen atom to form chlorine monoxide (ClO) and leaving an oxygen molecule (O
2). The ClO can react with a second molecule of ozone, releasing the chlorine atom and yielding two molecules of oxygen. The chemical shorthand for these gas-phase reactions is:

text:
Cl· + O
3 → ClO + O
2
A chlorine atom removes an oxygen atom from an ozone molecule to make a ClO molecule
ClO + O
3 → Cl· + 2 O
2
This ClO can also remove an oxygen atom from another ozone molecule; the chlorine is free to repeat this two-step cycle

tag: ul

text: The overall effect is a decrease in the amount of ozone, though the rate of these processes can be decreased by the effects of null cycles. More complicated mechanisms have also been discovered that lead to ozone destruction in the lower stratosphere.

text:
A single chlorine atom would continuously destroy ozone (thus a catalyst) for up to two years (the time scale for transport back down to the troposphere) were it not for reactions that remove them from this cycle by forming reservoir species such as hydrogen chloride (HCl) and chlorine nitrate (ClONO
2). Bromine is even more efficient than chlorine at destroying ozone on a per atom basis, but there is much less bromine in the atmosphere at present. Both chlorine and bromine contribute significantly to overall ozone depletion. Laboratory studies have also shown that fluorine and iodine atoms participate in analogous catalytic cycles. However, fluorine atoms react rapidly with water and methane to form strongly bound HF in the Earth's stratosphere, while organic molecules containing iodine react so rapidly in the lower atmosphere that they do not reach the stratosphere in significant quantities.

text: A single chlorine atom is able to react with an average of 100,000 ozone molecules before it is removed from the catalytic cycle. This fact plus the amount of chlorine released into the atmosphere yearly by chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) demonstrates the danger of CFCs and HCFCs to the environment.[6][7]

text: Observations on ozone layer depletion[edit]

text: The ozone hole is usually measured by reduction in the total column ozone above a point on the Earth's surface. This is normally expressed in Dobson units; abbreviated as "DU". The most prominent decrease in ozone has been in the lower stratosphere. Marked decreases in column ozone in the Antarctic spring and early summer compared to the early 1970s and before have been observed using instruments such as the Total Ozone Mapping Spectrometer (TOMS).[8]

text: Reductions of up to 70 percent in the ozone column observed in the austral (southern hemispheric) spring over Antarctica and first reported in 1985 (Farman et al.) are continuing. Antarctic total column ozone in September and October have continued to be 40–50 percent lower than pre-ozone-hole values since the 1990s.[1] A gradual trend toward "healing" was reported in 2016.[9] In 2017, NASA announced that the ozone hole was the weakest since 1988 because of warm stratospheric conditions. It is expected to recover around 2070.[10]

text: The amount lost is more variable year-to-year in the Arctic than in the Antarctic. The greatest Arctic declines are in the winter and spring, reaching up to 30 percent when the stratosphere is coldest.

text: Reactions that take place on polar stratospheric clouds (PSCs) play an important role in enhancing ozone depletion.[11] PSCs form more readily in the extreme cold of the Arctic and Antarctic stratosphere. This is why ozone holes first formed, and are deeper, over Antarctica. Early models failed to take PSCs into account and predicted a gradual global depletion, which is why the sudden Antarctic ozone hole was such a surprise to many scientists.[citation needed]

text: It is more accurate to speak of ozone depletion in middle latitudes rather than holes. Total column ozone declined below pre-1980 values between 1980 and 1996 for mid-latitudes. In the northern mid-latitudes, it then increased from the minimum value by about two percent from 1996 to 2009 as regulations took effect and the amount of chlorine in the stratosphere decreased. In the Southern Hemisphere's mid-latitudes, total ozone remained constant over that time period. There are no significant trends in the tropics, largely because halogen-containing compounds have not had time to break down and release chlorine and bromine atoms at tropical latitudes.[1][12]

text: Large volcanic eruptions have been shown to have substantial albeit uneven ozone-depleting effects, as observed with the 1991 eruption of Mt. Pinotubo in the Philippines.[13]

text:
Ozone depletion also explains much of the observed reduction in stratospheric and upper tropospheric temperatures.[14][15] The source of the warmth of the stratosphere is the absorption of UV radiation by ozone, hence reduced ozone leads to cooling. Some stratospheric cooling is also predicted from increases in greenhouse gases such as CO
2 and CFCs themselves; however, the ozone-induced cooling appears to be dominant.[16]

text: Predictions of ozone levels remain difficult, but the precision of models' predictions of observed values and the agreement among different modeling techniques have increased steadily.[1] The World Meteorological Organization Global Ozone Research and Monitoring Project—Report No. 44 comes out strongly in favor of the Montreal Protocol, but notes that a UNEP 1994 Assessment overestimated ozone loss for the 1994–1997 period.[17]

text: Chemicals in the atmosphere[edit]

text: CFCs and related compounds in the atmosphere[edit]

text: Chlorofluorocarbons (CFCs) and other halogenated ozone depleting substances (ODS) are mainly responsible for man-made chemical ozone depletion. The total amount of effective halogens (chlorine and bromine) in the stratosphere can be calculated and are known as the equivalent effective stratospheric chlorine (EESC).[18]

text: CFCs were invented by Thomas Midgley, Jr. in the 1930s. They were used in air conditioning and cooling units, as aerosol spray propellants prior to the 1970s, and in the cleaning processes of delicate electronic equipment. They also occur as by-products of some chemical processes. No significant natural sources have ever been identified for these compounds—their presence in the atmosphere is due almost entirely to human manufacture. As mentioned above, when such ozone-depleting chemicals reach the stratosphere, they are dissociated by ultraviolet light to release chlorine atoms. The chlorine atoms act as a catalyst, and each can break down tens of thousands of ozone molecules before being removed from the stratosphere. Given the longevity of CFC molecules, recovery times are measured in decades. It is calculated that a CFC molecule takes an average of about five to seven years to go from the ground level up to the upper atmosphere, and it can stay there for about a century, destroying up to one hundred thousand ozone molecules during that time.[19][verification needed]

text: 1,1,1-Trichloro-2,2,2-trifluoroethane, also known as CFC-113a, is one of four man-made chemicals newly discovered in the atmosphere by a team at the University of East Anglia. CFC-113a is the only known CFC whose abundance in the atmosphere is still growing. Its source remains a mystery, but illegal manufacturing is suspected by some. CFC-113a seems to have been accumulating unabated since 1960. Between 2010 and 2012, emissions of the gas jumped by 45 percent.[20][21]

text: Computer modeling[edit]

text: Scientists have attributed ozone depletion to the increase of man-made (anthropogenic) halogen compounds from CFCs by combining observational data with computer models. These complex chemistry transport models (e.g. SLIMCAT, CLaMS—Chemical Lagrangian Model of the Stratosphere) work by combining measurements of chemicals and meteorological fields with chemical reaction rate constants. They identify key chemical reactions and transport processes that bring CFC photolysis products into contact with ozone.

text: Ozone hole and its causes[edit]

text: The Antarctic ozone hole is an area of the Antarctic stratosphere in which the recent ozone levels have dropped to as low as 33 percent of their pre-1975 values. The ozone hole occurs during the Antarctic spring, from September to early December, as strong westerly winds start to circulate around the continent and create an atmospheric container. Within this polar vortex, over 50 percent of the lower stratospheric ozone is destroyed during the Antarctic spring.[23]

text: As explained above, the primary cause of ozone depletion is the presence of chlorine-containing source gases (primarily CFCs and related halocarbons). In the presence of UV light, these gases dissociate, releasing chlorine atoms, which then go on to catalyze ozone destruction. The Cl-catalyzed ozone depletion can take place in the gas phase, but it is dramatically enhanced in the presence of polar stratospheric clouds (PSCs).[24]

text: These polar stratospheric clouds (PSC) form during winter, in the extreme cold. Polar winters are dark, consisting of 3 months without solar radiation (sunlight). The lack of sunlight contributes to a decrease in temperature and the polar vortex traps and chills air. Temperatures hover around or below −80 °C. These low temperatures form cloud particles. There are three types of PSC clouds—nitric acid trihydrate clouds, slowly cooling water-ice clouds, and rapid cooling water-ice (nacerous) clouds—provide surfaces for chemical reactions whose products will, in the spring lead to ozone destruction.[25]

text:
The photochemical processes involved are complex but well understood. The key observation is that, ordinarily, most of the chlorine in the stratosphere resides in "reservoir" compounds, primarily chlorine nitrate (ClONO
2) as well as stable end products such as HCl. The formation of end products essentially remove Cl from the ozone depletion process. The former sequester Cl, which can be later made available via absorption of light at shorter wavelengths than 400 nm.[26] During the Antarctic winter and spring, however, reactions on the surface of the polar stratospheric cloud particles convert these "reservoir" compounds into reactive free radicals (Cl and ClO). The process by which the clouds remove NO
2 from the stratosphere by converting it to nitric acid in the PSC particles, which then are lost by sedimentation is called denitrification. This prevents newly formed ClO from being converted back into ClONO
2.

text:
The role of sunlight in ozone depletion is the reason why the Antarctic ozone depletion is greatest during spring. During winter, even though PSCs are at their most abundant, there is no light over the pole to drive chemical reactions. During the spring, however, the sun comes out, providing energy to drive photochemical reactions and melt the polar stratospheric clouds, releasing considerable ClO, which drives the hole mechanism. Further warming temperatures near the end of spring break up the vortex around mid-December. As warm, ozone and NO
2-rich air flows in from lower latitudes, the PSCs are destroyed, the enhanced ozone depletion process shuts down, and the ozone hole closes.[27]

text: Most of the ozone that is destroyed is in the lower stratosphere, in contrast to the much smaller ozone depletion through homogeneous gas phase reactions, which occurs primarily in the upper stratosphere.[28]

text: Interest in ozone layer depletion[edit]

text: Public misconceptions and misunderstandings of complex issues like the ozone depletion are common. The limited scientific knowledge of the public led to a confusion with global warming[29] or the perception of global warming as a subset of the "ozone hole".[30] In the beginning, classical green NGOs refrained from using CFC depletion for campaigning, as they assumed the topic was too complicated.[31] They became active much later, e.g. in Greenpeace's support for a CFC-free fridge produced by the former East German company VEB dkk Scharfenstein.[31][32]

text: The metaphors used in the CFC discussion (ozone shield, ozone hole) are not "exact" in the scientific sense. The "ozone hole" is more of a depression, less "a hole in the windshield". The ozone does not disappear through the layer, nor is there a uniform "thinning" of the ozone layer. However they resonated better with non-scientists and their concerns.[33] The ozone hole was seen as a "hot issue" and imminent risk[34] as lay people feared severe personal consequences such as skin cancer, cataracts, damage to plants, and reduction of plankton populations in the ocean's photic zone. Not only on the policy level, ozone regulation compared to climate change fared much better in public opinion. Americans voluntarily switched away from aerosol sprays before legislation was enforced, while climate change failed to achieve comparable concern and public action.[33] The sudden recognition in 1985 that there was a substantial "hole" was widely reported in the press. The especially rapid ozone depletion in Antarctica had previously been dismissed as a measurement error.[35] Scientific consensus was established after regulation.[31]

text: While the Antarctic ozone hole has a relatively small effect on global ozone, the hole has generated a great deal of public interest because:

text:
Many have worried that ozone holes might start appearing over other areas of the globe, though to date the only other large-scale depletion is a smaller ozone "dimple" observed during the Arctic spring around the North Pole. Ozone at middle latitudes has declined, but by a much smaller extent (about 4–5 percent decrease).
If stratospheric conditions become more severe (cooler temperatures, more clouds, more active chlorine), global ozone may decrease at a greater pace. Standard global warming theory predicts that the stratosphere will cool.[36]
When the Antarctic ozone hole breaks up each year, the ozone-depleted air drifts out into nearby regions. Decreases in the ozone level of up to 10 percent have been reported in New Zealand in the month following the breakup of the Antarctic ozone hole,[37] with ultraviolet-B radiation intensities increasing by more than 15 percent since the 1970s.[38][39]

text: Consequences of ozone layer depletion[edit]

text: Since the ozone layer absorbs UVB ultraviolet light from the sun, ozone layer depletion increases surface UVB levels (all else equal), which could lead to damage, including increase in skin cancer. This was the reason for the Montreal Protocol. Although decreases in stratospheric ozone are well-tied to CFCs and to increases in surface UVB, there is no direct observational evidence linking ozone depletion to higher incidence of skin cancer and eye damage in human beings. This is partly because UVA, which has also been implicated in some forms of skin cancer, is not absorbed by ozone, and because it is nearly impossible to control statistics for lifestyle changes over time.

text: Increased UV[edit]

text: Ozone, while a minority constituent in Earth's atmosphere, is responsible for most of the absorption of UVB radiation. The amount of UVB radiation that penetrates through the ozone layer decreases exponentially with the slant-path thickness and density of the layer. When stratospheric ozone levels decrease, higher levels of UVB reach the Earth’s surface.[1][40] UV-driven phenolic formation in tree rings has dated the start of ozone depletion in northern latitudes to the late 1700s.[41]

text: In October 2008, the Ecuadorian Space Agency published a report called HIPERION. The study used ground instruments in Ecuador and the last 28 years' data from 12 satellites of several countries, and found that the UV radiation reaching equatorial latitudes was far greater than expected, with the UV Index climbing as high as 24 in Quito; the WHO considers 11 as an extreme index and a great risk to health. The report concluded that depleted ozone levels around the mid-latitudes of the planet are already endangering large populations in these areas.[42] Later, the CONIDA, the Peruvian Space Agency, published its own study, which yielded almost the same findings as the Ecuadorian study.

text: Biological effects[edit]

text: The main public concern regarding the ozone hole has been the effects of increased surface UV radiation on human health. So far, ozone depletion in most locations has been typically a few percent and, as noted above, no direct evidence of health damage is available in most latitudes. If the high levels of depletion seen in the ozone hole were to be common across the globe, the effects could be substantially more dramatic. As the ozone hole over Antarctica has in some instances grown so large as to affect parts of Australia, New Zealand, Chile, Argentina, and South Africa, environmentalists have been concerned that the increase in surface UV could be significant.[43]

text: Ozone depletion would magnify all of the effects of UV on human health, both positive (including production of Vitamin D) and negative (including sunburn, skin cancer, and cataracts). In addition, increased surface UV leads to increased tropospheric ozone, which is a health risk to humans.

text: Basal and squamous cell carcinomas[edit]

text: The most common forms of skin cancer in humans, basal and squamous cell carcinomas, have been strongly linked to UVB exposure. The mechanism by which UVB induces these cancers is well understood—absorption of UVB radiation causes the pyrimidine bases in the DNA molecule to form dimers, resulting in transcription errors when the DNA replicates. These cancers are relatively mild and rarely fatal, although the treatment of squamous cell carcinoma sometimes requires extensive reconstructive surgery. By combining epidemiological data with results of animal studies, scientists have estimated that every one percent decrease in long-term stratospheric ozone would increase the incidence of these cancers by two percent.[44]

text: Malignant melanoma[edit]

text: Another form of skin cancer, malignant melanoma, is much less common but far more dangerous, being lethal in about 15–20 percent of the cases diagnosed. The relationship between malignant melanoma and ultraviolet exposure is not yet fully understood, but it appears that both UVB and UVA are involved. Because of this uncertainty, it is difficult to estimate the effect of ozone depletion on melanoma incidence. One study showed that a 10 percent increase in UVB radiation was associated with a 19 percent increase in melanomas for men and 16 percent for women.[45] A study of people in Punta Arenas, at the southern tip of Chile, showed a 56 percent increase in melanoma and a 46 percent increase in nonmelanoma skin cancer over a period of seven years, along with decreased ozone and increased UVB levels.[46]

text: Cortical cataracts[edit]

text: Epidemiological studies suggest an association between ocular cortical cataracts and UVB exposure, using crude approximations of exposure and various cataract assessment techniques. A detailed assessment of ocular exposure to UVB was carried out in a study on Chesapeake Bay Watermen, where increases in average annual ocular exposure were associated with increasing risk of cortical opacity.[47] In this highly exposed group of predominantly white males, the evidence linking cortical opacities to sunlight exposure was the strongest to date. Based on these results, ozone depletion is predicted to cause hundreds of thousands of additional cataracts by 2050.[48]

text: Increased tropospheric ozone[edit]

text: Increased surface UV leads to increased tropospheric ozone. Ground-level ozone is generally recognized to be a health risk, as ozone is toxic due to its strong oxidant properties. The risks are particularly high for young children, the elderly, and those with asthma or other respiratory difficulties. At this time, ozone at ground level is produced mainly by the action of UV radiation on combustion gases from vehicle exhausts.[49]

text: Increased production of vitamin D[edit]

text: Vitamin D is produced in the skin by ultraviolet light. Thus, higher UVB exposure raises human vitamin D in those deficient in it. Recent research (primarily since the Montreal Protocol) shows that many humans have less than optimal vitamin D levels. In particular, in the U.S. population, the lowest quarter of vitamin D (<17.8 ng/ml) were found using information from the National Health and Nutrition Examination Survey to be associated with an increase in all-cause mortality in the general population.[50] While blood level of Vitamin D in excess of 100 ng/ml appear to raise blood calcium excessively and to be associated with higher mortality, the body has mechanisms that prevent sunlight from producing Vitamin D in excess of the body's requirements.[51]

text: Effects on non-human animals[edit]

text: A November 2010 report by scientists at the Institute of Zoology in London found that whales off the coast of California have shown a sharp rise in sun damage, and these scientists "fear that the thinning ozone layer is to blame".[52] The study photographed and took skin biopsies from over 150 whales in the Gulf of California and found "widespread evidence of epidermal damage commonly associated with acute and severe sunburn", having cells that form when the DNA is damaged by UV radiation. The findings suggest "rising UV levels as a result of ozone depletion are to blame for the observed skin damage, in the same way that human skin cancer rates have been on the increase in recent decades."[53]

text: Effects on crops[edit]

text: An increase of UV radiation would be expected to affect crops. A number of economically important species of plants, such as rice, depend on cyanobacteria residing on their roots for the retention of nitrogen. Cyanobacteria are sensitive to UV radiation and would be affected by its increase.[54] "Despite mechanisms to reduce or repair the effects of increased ultraviolet radiation, plants have a limited ability to adapt to increased levels of UVB, therefore plant growth can be directly affected by UVB radiation."[55]

text: Public policy[edit]

text: The full extent of the damage that CFCs have caused to the ozone layer is not known and will not be known for decades; however, marked decreases in column ozone have already been observed. The Montreal and Vienna conventions were installed long before a scientific consensus was established or important uncertainties in the science field were being resolved.[31] The ozone case was understood comparably well by lay persons as e.g. Ozone shield or ozone hole were useful "easy-to-understand bridging metaphors".[33] Americans voluntarily switched away from aerosol sprays, resulting in a 50 percent sales loss even before legislation was enforced.[33]

text: After a 1976 report by the United States National Academy of Sciences concluded that credible scientific evidence supported the ozone depletion hypothesis[56] a few countries, including the United States, Canada, Sweden, Denmark, and Norway, moved to eliminate the use of CFCs in aerosol spray cans.[57] At the time this was widely regarded as a first step towards a more comprehensive regulation policy, but progress in this direction slowed in subsequent years, due to a combination of political factors (continued resistance from the halocarbon industry and a general change in attitude towards environmental regulation during the first two years of the Reagan administration) and scientific developments (subsequent National Academy assessments that indicated that the first estimates of the magnitude of ozone depletion had been overly large). A critical DuPont manufacturing patent for Freon was set to expire in 1979. The United States banned the use of CFCs in aerosol cans in 1978.[57] The European Community rejected proposals to ban CFCs in aerosol sprays, and in the U.S., CFCs continued to be used as refrigerants and for cleaning circuit boards. Worldwide CFC production fell sharply after the U.S. aerosol ban, but by 1986 had returned nearly to its 1976 level.[57] In 1993, DuPont Canada closed its CFC facility.[58]

text: The U.S. Government's attitude began to change again in 1983, when William Ruckelshaus replaced Anne M. Burford as Administrator of the United States Environmental Protection Agency. Under Ruckelshaus and his successor, Lee Thomas, the EPA pushed for an international approach to halocarbon regulations. In 1985 20 nations, including most of the major CFC producers, signed the Vienna Convention for the Protection of the Ozone Layer, which established a framework for negotiating international regulations on ozone-depleting substances. That same year, the discovery of the Antarctic ozone hole was announced, causing a revival in public attention to the issue. In 1987, representatives from 43 nations signed the Montreal Protocol. Meanwhile, the halocarbon industry shifted its position and started supporting a protocol to limit CFC production. However, this shift was uneven with DuPont acting more quickly than their European counterparts. DuPont may have feared court action related to increased skin cancer especially as the EPA had published a study in 1986 claiming that an additional 40 million cases and 800,000 cancer deaths were to be expected in the U.S. in the next 88 years.[59] The EU shifted its position as well after Germany gave up its defence of the CFC industry and started supporting moves towards regulation. Government and industry in France and the UK tried to defend their CFC producing industries even after the Montreal Protocol had been signed.[60]

text: At Montreal, the participants agreed to freeze production of CFCs at 1986 levels and to reduce production by 50 percent by 1999.[57] After a series of scientific expeditions to the Antarctic produced convincing evidence that the ozone hole was indeed caused by chlorine and bromine from manmade organohalogens, the Montreal Protocol was strengthened at a 1990 meeting in London. The participants agreed to phase out CFCs and halons entirely (aside from a very small amount marked for certain "essential" uses, such as asthma inhalers) by 2000 in non-Article 5 countries and by 2010 in Article 5 (less developed) signatories.[61] At a 1992 meeting in Copenhagen, the phase-out date was moved up to 1996.[61] At the same meeting, methyl bromide (MeBr), a fumigant used primarily in agricultural production, was added to the list of controlled substances. For all substances controlled under the protocol, phaseout schedules were delayed for less developed ('Article 5(1)') countries, and phaseout in these countries was supported by transfers of expertise, technology, and money from non-Article 5(1) Parties to the Protocol. Additionally, exemptions from the agreed schedules could be applied for under the Essential Use Exemption (EUE) process for substances other than methyl bromide and under the Critical Use Exemption (CUE) process for methyl bromide.[62][63]

text: Civil society including especially NGOs, played critical roles at all stages of policy development leading up to the Vienna Conference, the Montreal Protocol, and in assessing compliance afterwards.[64][65][66][67] The major companies claimed that no alternatives to HFC existed.[68] An ozone-safe hydrocarbon refrigerant was developed at a Hamburg technological institute in Germany, and in 1992 came to the attention of the non-governmental organization (NGO) Greenpeace. Greenpeace was given the patent, called it "Greenfreeze," and left the patent as open source.[69][70] The NGO then worked successfully first with a small and struggling company to market an appliance beginning in Europe, then Asia and later Latin America, receiving a 1997 UNEP award.[71][72] By 1995, Germany had already made CFC refrigerators illegal.[72] Since 2004, corporations like Coca-Cola, Carlsberg, and IKEA have been forming a coalition to promote the ozone-safe Greenfreeze units. Production spread to companies like Electrolux, Bosch, and LG, with sales reaching some 300 million refrigerators by 2008.[71][73] In Latin America, a domestic Argentinian company began Greenfreeze production in 2003, while the giant Bosch in Brazil began a year later.[74][75] By 2013 it was being used by some 700 million refrigerators, making up about 40 percent of the market.[68] In the U.S., however, change has been much slower. To some extent, CFCs were being replaced by the less damaging hydrochlorofluorocarbons (HCFCs), although concerns remain regarding HCFCs also. In some applications, hydrofluorocarbons (HFCs) were being used to replace CFCs. HFCs, which contain no chlorine or bromine, do not contribute at all to ozone depletion although they are potent greenhouse gases. The best known of these compounds is probably HFC-134a (R-134a), which in the United States has largely replaced CFC-12 (R-12) in automobile air conditioners. In laboratory analytics (a former "essential" use) the ozone depleting substances can be replaced with various other solvents.[76] Chemical companies like Du Pont, whose representatives even disparaged Greenfreeze as "that German technology," maneuvered the EPA to block the technology in the U.S. until 2011.[77][78][79][80] Ben & Jerry's of Unilever and General Electric, spurred by Greenpeace, had expressed formal interest in 2008 which figured in the EPA's final approval.[71][81]

text: More recently, policy experts have advocated for efforts to link ozone protection efforts to climate protection efforts.[82][83] Many ODS are also greenhouse gases, some thousands of times more powerful agents of radiative forcing than carbon dioxide over the short and medium term. Thus policies protecting the ozone layer have had benefits in mitigating climate change. In fact, the reduction of the radiative forcing due to ODS probably masked the true level of climate change effects of other GHGs, and was responsible for the "slow down" of global warming from the mid-90s.[84] Policy decisions in one arena affect the costs and effectiveness of environmental improvements in the other.

text: ODS requirements in the marine industry[edit]

text: The IMO has amended MARPOL Annex VI Regulation 12 regarding ozone depleting substances. As from July 1, 2010, all vessels where MARPOL Annex VI is applicable should have a list of equipment using ozone depleting substances. The list should include name of ODS, type and location of equipment, quantity in kg and date. All changes since that date should be recorded in an ODS Record book on board recording all intended or unintended releases to the atmosphere. Furthermore, new ODS supply or landing to shore facilities should be recorded as well.

text: Prospects of ozone depletion[edit]

text:
Since the adoption and strengthening of the Montreal Protocol has led to reductions in the emissions of CFCs, atmospheric concentrations of the most-significant compounds have been declining. These substances are being gradually removed from the atmosphere; since peaking in 1994, the Effective Equivalent Chlorine (EECl) level in the atmosphere had dropped about 10 percent by 2008. The decrease in ozone-depleting chemicals has also been significantly affected by a decrease in bromine-containing chemicals. The data suggest that substantial natural sources exist for atmospheric methyl bromide (CH
3Br).[1] The phase-out of CFCs means that nitrous oxide (N
2O), which is not covered by the Montreal Protocol, has become the most highly emitted ozone-depleting substance and is expected to remain so throughout the 21st century.[85]

text: A 2005 IPCC review of ozone observations and model calculations concluded that the global amount of ozone has now approximately stabilized. Although considerable variability is expected from year to year, including in polar regions where depletion is largest, the ozone layer is expected to begin to recover in coming decades due to declining ozone-depleting substance concentrations, assuming full compliance with the Montreal Protocol.[86]

text: The Antarctic ozone hole is expected to continue for decades. Ozone concentrations in the lower stratosphere over Antarctica will increase by 5–10 percent by 2020 and return to pre-1980 levels by about 2060–2075. This is 10–25 years later than predicted in earlier assessments, because of revised estimates of atmospheric concentrations of ozone-depleting substances, including a larger predicted future usage in developing countries. Another factor that may prolong ozone depletion is the drawdown of nitrogen oxides from above the stratosphere due to changing wind patterns.[87] A gradual trend toward "healing" was reported in 2016.[9]

text: Research history[edit]

text:
The basic physical and chemical processes that lead to the formation of an ozone layer in the Earth's stratosphere were discovered by Sydney Chapman in 1930. Short-wavelength UV radiation splits an oxygen (O
2) molecule into two oxygen (O) atoms, which then combine with other oxygen molecules to form ozone. Ozone is removed when an oxygen atom and an ozone molecule "recombine" to form two oxygen molecules, i.e. O + O
3 → 2O
2. In the 1950s, David Bates and Marcel Nicolet presented evidence that various free radicals, in particular hydroxyl (OH) and nitric oxide (NO), could catalyze this recombination reaction, reducing the overall amount of ozone. These free radicals were known to be present in the stratosphere, and so were regarded as part of the natural balance—it was estimated that in their absence, the ozone layer would be about twice as thick as it currently is.

text:
In 1970 Paul Crutzen pointed out that emissions of nitrous oxide (N
2O), a stable, long-lived gas produced by soil bacteria, from the Earth's surface could affect the amount of nitric oxide (NO) in the stratosphere. Crutzen showed that nitrous oxide lives long enough to reach the stratosphere, where it is converted into NO. Crutzen then noted that increasing use of fertilizers might have led to an increase in nitrous oxide emissions over the natural background, which would in turn result in an increase in the amount of NO in the stratosphere. Thus human activity could affect the stratospheric ozone layer. In the following year, Crutzen and (independently) Harold Johnston suggested that NO emissions from supersonic passenger aircraft, which would fly in the lower stratosphere, could also deplete the ozone layer. However, more recent analysis in 1995 by David W. Fahey, an atmospheric scientist at the National Oceanic and Atmospheric Administration, found that the drop in ozone would be from 1–2 percent if a fleet of 500 supersonic passenger aircraft were operated.[88] This, Fahey expressed, would not be a showstopper for advanced supersonic passenger aircraft development.[89]

text: Rowland–Molina hypothesis[edit]

text:
In 1974 Frank Sherwood Rowland, Chemistry Professor at the University of California at Irvine, and his postdoctoral associate Mario J. Molina suggested that long-lived organic halogen compounds, such as CFCs, might behave in a similar fashion as Crutzen had proposed for nitrous oxide. James Lovelock had recently discovered, during a cruise in the South Atlantic in 1971, that almost all of the CFC compounds manufactured since their invention in 1930 were still present in the atmosphere. Molina and Rowland concluded that, like N
2O, the CFCs would reach the stratosphere where they would be dissociated by UV light, releasing chlorine atoms. A year earlier, Richard Stolarski and Ralph Cicerone at the University of Michigan had shown that Cl is even more efficient than NO at catalyzing the destruction of ozone. Similar conclusions were reached by Michael McElroy and Steven Wofsy at Harvard University. Neither group, however, had realized that CFCs were a potentially large source of stratospheric chlorine—instead, they had been investigating the possible effects of HCl emissions from the Space Shuttle, which are very much smaller.

text:
The Rowland–Molina hypothesis was strongly disputed by representatives of the aerosol and halocarbon industries. The Chair of the Board of DuPont was quoted as saying that ozone depletion theory is "a science fiction tale … a load of rubbish … utter nonsense".[90] Robert Abplanalp, the President of Precision Valve Corporation (and inventor of the first practical aerosol spray can valve), wrote to the Chancellor of UC Irvine to complain about Rowland's public statements.[91] Nevertheless, within three years most of the basic assumptions made by Rowland and Molina were confirmed by laboratory measurements and by direct observation in the stratosphere. The concentrations of the source gases (CFCs and related compounds) and the chlorine reservoir species (HCl and ClONO
2) were measured throughout the stratosphere, and demonstrated that CFCs were indeed the major source of stratospheric chlorine, and that nearly all of the CFCs emitted would eventually reach the stratosphere. Even more convincing was the measurement, by James G. Anderson and collaborators, of chlorine monoxide (ClO) in the stratosphere. ClO is produced by the reaction of Cl with ozone—its observation thus demonstrated that Cl radicals not only were present in the stratosphere but also were actually involved in destroying ozone. McElroy and Wofsy extended the work of Rowland and Molina by showing that bromine atoms were even more effective catalysts for ozone loss than chlorine atoms and argued that the brominated organic compounds known as halons, widely used in fire extinguishers, were a potentially large source of stratospheric bromine. In 1976 the United States National Academy of Sciences released a report concluding that the ozone depletion hypothesis was strongly supported by the scientific evidence. In response the United States, Canada and Norway banned the use of CFCs in aerosol spray cans in 1978. Early estimates were that, if CFC production continued at 1977 levels, the total atmospheric ozone would after a century or so reach a steady state, 15 to 18 percent below normal levels. By 1984, when better evidence on the speed of critical reactions was available, this estimate was changed to 5 to 9 percent steady-state depletion.[92]

text: Crutzen, Molina, and Rowland were awarded the 1995 Nobel Prize in Chemistry for their work on stratospheric ozone.

text: Antarctic ozone hole[edit]

text: The discovery of the Antarctic "ozone hole" by British Antarctic Survey scientists Farman, Gardiner and Shanklin (first reported in a paper in Nature in May 1985[93]) came as a shock to the scientific community, because the observed decline in polar ozone was far larger than anyone had anticipated.[35] Satellite measurements showing massive depletion of ozone around the south pole were becoming available at the same time. However, these were initially rejected as unreasonable by data quality control algorithms (they were filtered out as errors since the values were unexpectedly low); the ozone hole was detected only in satellite data when the raw data was reprocessed following evidence of ozone depletion in in situ observations.[60] When the software was rerun without the flags, the ozone hole was seen as far back as 1976.[94]

text: Susan Solomon, an atmospheric chemist at the National Oceanic and Atmospheric Administration (NOAA), proposed that chemical reactions on polar stratospheric clouds (PSCs) in the cold Antarctic stratosphere caused a massive, though localized and seasonal, increase in the amount of chlorine present in active, ozone-destroying forms. The polar stratospheric clouds in Antarctica are only formed when there are very low temperatures, as low as −80 °C, and early spring conditions. In such conditions the ice crystals of the cloud provide a suitable surface for conversion of unreactive chlorine compounds into reactive chlorine compounds, which can deplete ozone easily.

text: Moreover, the polar vortex formed over Antarctica is very tight and the reaction occurring on the surface of the cloud crystals is far different from when it occurs in atmosphere. These conditions have led to ozone hole formation in Antarctica. This hypothesis was decisively confirmed, first by laboratory measurements and subsequently by direct measurements, from the ground and from high-altitude airplanes, of very high concentrations of chlorine monoxide (ClO) in the Antarctic stratosphere.[95]

text: Alternative hypotheses, which had attributed the ozone hole to variations in solar UV radiation or to changes in atmospheric circulation patterns, were also tested and shown to be untenable.[citation needed]

text: Meanwhile, analysis of ozone measurements from the worldwide network of ground-based Dobson spectrophotometers led an international panel to conclude that the ozone layer was in fact being depleted, at all latitudes outside of the tropics.[12] These trends were confirmed by satellite measurements. As a consequence, the major halocarbon-producing nations agreed to phase out production of CFCs, halons, and related compounds, a process that was completed in 1996.

text: Since 1981 the United Nations Environment Programme, under the auspices of the World Meteorological Organization, has sponsored a series of technical reports on the Scientific Assessment of Ozone Depletion, based on satellite measurements. The 2007 report showed that the hole in the ozone layer was recovering and the smallest it had been for about a decade.[96] The 2010 report found, "Over the past decade, global ozone and ozone in the Arctic and Antarctic regions is no longer decreasing but is not yet increasing. The ozone layer outside the Polar regions is projected to recover to its pre-1980 levels some time before the middle of this century. In contrast, the springtime ozone hole over the Antarctic is expected to recover much later."[97] In 2012, NOAA and NASA reported "Warmer air temperatures high above the Antarctic led to the second smallest season ozone hole in 20 years averaging 17.9 million square kilometres. The hole reached its maximum size for the season on Sept 22, stretching to 21.2 million square kilometres."[98] A gradual trend toward "healing" was reported in 2016.[9]

text: The hole in the Earth's ozone layer over the South Pole has affected atmospheric circulation in the Southern Hemisphere all the way to the equator.[99] The ozone hole has influenced atmospheric circulation all the way to the tropics and increased rainfall at low, subtropical latitudes in the Southern Hemisphere.

text: Arctic ozone hole[edit]

text: On March 3, 2005, the journal Nature[100] published an article linking 2004's unusually large Arctic ozone hole to solar wind activity.

text: On March 15, 2011, a record ozone layer loss was observed, with about half of the ozone present over the Arctic having been destroyed.[101][102][103] The change was attributed to increasingly cold winters in the Arctic stratosphere at an altitude of approximately 20 km (12 mi), a change associated with global warming in a relationship that is still under investigation.[102] By March 25, the ozone loss had become the largest compared to that observed in all previous winters with the possibility that it would become an ozone hole.[104] This would require that the quantities of ozone to fall below 200 Dobson units, from the 250 recorded over central Siberia.[104] It is predicted that the thinning layer would affect parts of Scandinavia and Eastern Europe on March 30–31.[104]

text: On October 2, 2011, a study was published in the journal Nature, which said that between December 2010 and March 2011 up to 80 percent of the ozone in the atmosphere at about 20 kilometres (12 mi) above the surface was destroyed.[105] The level of ozone depletion was severe enough that scientists said it could be compared to the ozone hole that forms over Antarctica every winter.[105] According to the study, "for the first time, sufficient loss occurred to reasonably be described as an Arctic ozone hole."[105] The study analyzed data from the Aura and CALIPSO satellites, and determined that the larger-than-normal ozone loss was due to an unusually long period of cold weather in the Arctic, some 30 days more than typical, which allowed for more ozone-destroying chlorine compounds to be created.[106] According to Lamont Poole, a co-author of the study, cloud and aerosol particles on which the chlorine compounds are found "were abundant in the Arctic until mid March 2011—much later than usual—with average amounts at some altitudes similar to those observed in the Antarctic, and dramatically larger than the near-zero values seen in March in most Arctic winters".[106]

text: Tibet ozone hole[edit]

text: As winters that are colder are more affected, at times there is an ozone hole over Tibet. In 2006, a 2.5 million square kilometer ozone hole was detected over Tibet.[107] Also again in 2011 an ozone hole appeared over mountainous regions of Tibet, Xinjiang, Qinghai and the Hindu Kush, along with an unprecedented hole over the Arctic, though the Tibet one is far less intense than the ones over the Arctic or Antarctic.[108]

text: Potential depletion by storm clouds[edit]

text: Research in 2012 showed that the same process that produces the ozone hole over Antarctica occurs over summer storm clouds in the United States, and thus may be destroying ozone there as well.[109][110]

text: Ozone depletion and global warming[edit]

text: Among others, Robert Watson had a role in the science assessment and in the regulation efforts of ozone depletion and global warming.[31] Prior to the 1980s, the EU, NASA, NAS, UNEP, WMO and the British government had dissenting scientific reports and Watson played a role in the process of unified assessments. Based on the experience with the ozone case, the IPCC started to work on a unified reporting and science assessment[31] to reach a consensus to provide the IPCC Summary for Policymakers.

text: There are various areas of linkage between ozone depletion and global warming science:

text:
The same CO
2 radiative forcing that produces global warming is expected to cool the stratosphere.[111] This cooling, in turn, is expected to produce a relative increase in ozone (O
3) depletion in polar area and the frequency of ozone holes.[112]
Conversely, ozone depletion represents a radiative forcing of the climate system. There are two opposing effects: Reduced ozone causes the stratosphere to absorb less solar radiation, thus cooling the stratosphere while warming the troposphere; the resulting colder stratosphere emits less long-wave radiation downward, thus cooling the troposphere. Overall, the cooling dominates; the IPCC concludes "observed stratospheric O
3 losses over the past two decades have caused a negative forcing of the surface-troposphere system"[14] of about −0.15 ± 0.10 watts per square meter (W/m2).[86]
One of the strongest predictions of the greenhouse effect is that the stratosphere will cool.[111] Although this cooling has been observed, it is not trivial to separate the effects of changes in the concentration of greenhouse gases and ozone depletion since both will lead to cooling. However, this can be done by numerical stratospheric modeling. Results from the National Oceanic and Atmospheric Administration's Geophysical Fluid Dynamics Laboratory show that above 20 km (12 mi), the greenhouse gases dominate the cooling.[113]
As noted under 'Public Policy', ozone depleting chemicals are also often greenhouse gases. The increases in concentrations of these chemicals have produced 0.34 ± 0.03 W/m2 of radiative forcing, corresponding to about 14 percent of the total radiative forcing from increases in the concentrations of well-mixed greenhouse gases.[86]
The long term modeling of the process, its measurement, study, design of theories and testing take decades to document, gain wide acceptance, and ultimately become the dominant paradigm. Several theories about the destruction of ozone were hypothesized in the 1980s, published in the late 1990s, and are currently being investigated. Dr Drew Schindell, and Dr Paul Newman, NASA Goddard, proposed a theory in the late 1990s, using computational modeling methods to model ozone destruction, that accounted for 78 percent of the ozone destroyed. Further refinement of that model accounted for 89 percent of the ozone destroyed, but pushed back the estimated recovery of the ozone hole from 75 years to 150 years. (An important part of that model is the lack of stratospheric flight due to depletion of fossil fuels.)

text: Misconceptions[edit]

text: CFC weight[edit]

text: Since CFC molecules are heavier than air (nitrogen or oxygen), it is commonly believed that the CFC molecules cannot reach the stratosphere in significant amount.[114] However, atmospheric gases are not sorted by weight; the forces of wind can fully mix the gases in the atmosphere. Lighter CFCs are evenly distributed throughout the turbosphere and reach the upper atmosphere,[115] although some of the heavier CFCs are not evenly distributed.[116]

text: Percentage of man-made chlorine[edit]

text: Another misconception is that "it is generally accepted that natural sources of tropospheric chlorine are four to five times larger than man-made ones." While strictly true, tropospheric chlorine is irrelevant; it is stratospheric chlorine that affects ozone depletion. Chlorine from ocean spray is soluble and thus is washed by rainfall before it reaches the stratosphere. CFCs, in contrast, are insoluble and long-lived, allowing them to reach the stratosphere. In the lower atmosphere, there is much more chlorine from CFCs and related haloalkanes than there is in HCl from salt spray, and in the stratosphere halocarbons are dominant.[117] Only methyl chloride, which is one of these halocarbons, has a mainly natural source,[118] and it is responsible for about 20 percent of the chlorine in the stratosphere; the remaining 80 percent comes from manmade sources.

text: Very violent volcanic eruptions can inject HCl into the stratosphere, but researchers[119] have shown that the contribution is not significant compared to that from CFCs. A similar erroneous assertion is that soluble halogen compounds from the volcanic plume of Mount Erebus on Ross Island, Antarctica are a major contributor to the Antarctic ozone hole.[119]

text: Nevertheless, a 2015 study[120] showed that the role of Mount Erebus volcano in the Antarctic ozone depletion was probably underestimated. Based on the NCEP/NCAR reanalysis data over the last 35 years and by using the NOAA HYSPLIT trajectory model, researchers showed that Erebus volcano gas emissions (including hydrogen chloride (HCl)) can reach the Antarctic stratosphere via high-latitude cyclones and then the polar vortex. Depending on Erebus volcano activity, the additional annual HCl mass entering the stratosphere from Erebus varies from 1.0 to 14.3 kt.

text: First observation[edit]

text: G.M.B. Dobson (Exploring the Atmosphere, 2nd Edition, Oxford, 1968) mentioned that when springtime ozone levels in the Antarctic over Halley Bay were first measured in 1956, he was surprised to find that they were ~320 DU, or about 150 DU below spring Arctic levels of ~450 DU. These were at that time the only known Antarctic ozone values available. What Dobson describes is essentially the baseline from which the ozone hole is measured: actual ozone hole values are in the 150–100 DU range.

text: The discrepancy between the Arctic and Antarctic noted by Dobson was primarily a matter of timing: during the Arctic spring ozone levels rose smoothly, peaking in April, whereas in the Antarctic they stayed approximately constant during early spring, rising abruptly in November when the polar vortex broke down.

text: The behavior seen in the Antarctic ozone hole is completely different. Instead of staying constant, early springtime ozone levels suddenly drop from their already low winter values, by as much as 50 percent, and normal values are not reached again until December.[121]

text: Location of hole[edit]

text: Some people thought that the ozone hole should be above the sources of CFCs. However, CFCs are well mixed globally in the troposphere and stratosphere. The reason for occurrence of the ozone hole above Antarctica is not because there are more CFCs concentrated but because the low temperatures help form polar stratospheric clouds.[122] In fact, there are findings of significant and localized "ozone holes" above other parts of the earth.[123][better source needed]

text: World Ozone Day[edit]

text: In 1994, the United Nations General Assembly voted to designate September 16 as the International Day for the Preservation of the Ozone Layer, or "World Ozone Day", to commemorate the signing of the Montreal Protocol on that date in 1987.[124]


document_title: Extreme points of North America

question_text: the north american country that is farthest north

text: Extreme points of North America

text: North America and surrounding islands[edit]

text:
Northernmost point — Kaffeklubben Island, Greenland 83°40′N 29°50′W / 83.667°N 29.833°W / 83.667; -29.833 (Kaffeklubben Island). Although politically part of the Kingdom of Denmark, Greenland is geologically part of the North American plate. If Greenland is excluded from North America, the northernmost point is Cape Columbia, Ellesmere Island, Nunavut, Canada 83°8′N 74°13′W / 83.133°N 74.217°W / 83.133; -74.217 (Cape Columbia).
Southernmost point — Cocos Island, Costa Rica 5°31′8″N 87°4′18″W / 5.51889°N 87.07167°W / 5.51889; -87.07167 (Cocos Island)
Westernmost point — The westernmost point depends on the definition of "westernmost". If following the International Date Line, it would be Cape Wrangell on Attu Island, Alaska, United States 52°55′28″N 172°28′22″E / 52.92444°N 172.47278°E / 52.92444; 172.47278 (Cape Wrangell). However, if the border between east and west is defined by the 180th meridian, the westernmost point is the West Point of Amatignak Island 51°17′N 179°9′W / 51.283°N 179.150°W / 51.283; -179.150 (West Point of Amatignak Island), as Attu Island is in the Eastern Hemisphere.
Easternmost point — Nordostrundingen, Greenland 81°26′25″N 11°29′22″W / 81.44028°N 11.48944°W / 81.44028; -11.48944 (Nordostrundingen). If Greenland is excluded, then the easternmost point is Cape Spear, Newfoundland, Canada 47°31′25″N 52°37′10″W / 47.52361°N 52.61944°W / 47.52361; -52.61944 (Cape Spear). Again, if one uses the technical definition of longitude, it is Pochnoi Point on Semisopochnoi Island, Alaska, 51°57′N 179°52′E / 51.950°N 179.867°E / 51.950; 179.867 (Pochnoi Point) since the state stretches into the Eastern Hemisphere.

text: Continental North America[edit]

text:
Northernmost point — Zenith Point, Canada 72°0′0″N 94°38′59″W / 72.00000°N 94.64972°W / 72.00000; -94.64972 (Zenith Point)
Southernmost point — Punta Mariato, Panama 7°12′32″N 80°53′10″W / 7.20889°N 80.88611°W / 7.20889; -80.88611 (Punta Mariato)
Westernmost point — Cape Prince of Wales, Alaska 65°35′47″N 168°5′5″W / 65.59639°N 168.08472°W / 65.59639; -168.08472 (Cape Prince of Wales)
Easternmost point — Cape Saint Charles, Labrador 52°13′3″N 55°37′15″W / 52.21750°N 55.62083°W / 52.21750; -55.62083 (Cape Saint Charles)

text: Highest points[edit]

text:
Denali (Mount McKinley), Alaska, United States 63°4′10″N 151°0′26″W / 63.06944°N 151.00722°W / 63.06944; -151.00722 (Mount McKinley) — highest summit of North America at 6,190.5 m (20,310 feet).[1]
Pico de Orizaba (Volcán Citlaltépetl),[note 1][2] Puebla and Veracruz, Mexico 19°1′50″N 97°16′11″W / 19.03056°N 97.26972°W / 19.03056; -97.26972 (Pico de Orizaba) — highest volcano summit of North America at 5,636 m (18,491 feet).
Grays Peak,[note 2][3][4][note 3] Colorado, United States 39°38′2″N 105°49′3″W / 39.63389°N 105.81750°W / 39.63389; -105.81750 (Grays Peak) — highest point on the Continental Divide of North America at 4,352 m (14,278 feet).
Volcán Tajumulco,[note 4][5] San Marcos, Guatemala 15°2′37″N 91°54′12″W / 15.04361°N 91.90333°W / 15.04361; -91.90333 (Volcán Tajumulco) — highest summit of Central America at 4,220 m (13,850 feet).
Gunnbjørn Fjeld,[note 5][6] Sermersooq, Island of Greenland, Greenland 68°55′10″N 29°53′55″W / 68.91944°N 29.89861°W / 68.91944; -29.89861 (Gunnbjørn Fjeld) — highest island summit of the Americas and the Western Hemisphere and highest summit of the entire Arctic at 3,694 m (12,119 feet).
Pico Duarte,[note 6][7] Dominican Republic, Hispaniola 19°1′23″N 70°59′53″W / 19.02306°N 70.99806°W / 19.02306; -70.99806 (Pico Duarte) — highest summit of the Caribbean at 3,175 m (10,417 feet).
Ixchiguán, San Marcos Department, Guatemala — highest town of North America at 3200m  m (10,500 feet)
Leadville, Colorado, United States 39°14′50″N 106°17′30″W / 39.24722°N 106.29167°W / 39.24722; -106.29167 (Leadville, Colorado) — highest city of North America at 3094 m (10,152 feet)
Lake County Airport, Colorado, United States 39°13′13″N 106°19′00″W / 39.22028°N 106.31667°W / 39.22028; -106.31667 (Lake County Airport) — highest airfield of North America at 3026 m (9,927 feet)

text: Lowest points[edit]

text:
Badwater Basin, Death Valley, California, United States 36°14′23″N 116°50′5″W / 36.23972°N 116.83472°W / 36.23972; -116.83472 (Badwater Basin) — lowest land surface of North America at −85.0 m (−279 feet)[8]
Salton Sea, California, United States 33°19′59″N 115°50′3″W / 33.33306°N 115.83417°W / 33.33306; -115.83417 (Salton Sea) — lowest lake of North America at −69 m (−226 feet)
Furnace Creek Airport, California, United States 36°27′50″N 116°52′53″W / 36.46389°N 116.88139°W / 36.46389; -116.88139 (Furnace Creek Airport) — lowest airfield of the Americas at −64 m (−210 feet)
Furnace Creek,[9] California, United States 36°27′29″N 116°52′15″W / 36.45806°N 116.87083°W / 36.45806; -116.87083 (Furnace Creek, California) — lowest settlement of the Americas at −58 m (−190 ft)
Calipatria, California, United States 33°07′32″N 115°30′51″W / 33.12556°N 115.51417°W / 33.12556; -115.51417 (Calipatria, California) — lowest city of the Americas at −56 m (−184 feet)
Lago Enriquillo, Dominican Republic, Hispaniola 18°30′N 71°35′W / 18.500°N 71.583°W / 18.500; -71.583 (Lago Enriquillo) — lowest lake on an island and lowest surface point on any ocean island on Earth at −27 m (−89 feet)
New Orleans, Louisiana, United States 29°58′N 90°03′W / 29.967°N 90.050°W / 29.967; -90.050 (New Orleans, Louisiana) — lowest city of the Americas with an average elevation of −0.5 m (−1.5 feet)
Isthmus of Rivas, Rivas, Nicaragua 12°1′N 86°27′W / 12.017°N 86.450°W / 12.017; -86.450 (Isthmus of Rivas) — lowest pass between Caribbean Sea and Pacific Ocean (on the Continental Divide of the Americas) at 56 m (184 feet)
Great Slave Lake bottom, Northwest Territories, Canada 61°40′N 114°00′W / 61.667°N 114.000°W / 61.667; -114.000 (Great Slave Lake) — lowest fresh water point of the Americas at −458 m (−1,503 feet)

text: Other points[edit]

text:
The geographic center of the North American continent is located at 48°10′N 100°10′W / 48.167°N 100.167°W / 48.167; -100.167 (Geographic center of the North American continent), about 6 miles west of Balta in Pierce County, North Dakota, United States.
The North American pole of inaccessibility is located at 43°22′N 101°58′W / 43.367°N 101.967°W / 43.367; -101.967 (North American pole of inaccessibility), about eleven miles southeast of the town of Kyle on the Pine Ridge Indian Reservation in Bennett County, South Dakota, United States, 1650 km (1025 miles) from the nearest coastlines.

text: Islands[edit]

text:
Island of Greenland 68°55′10″N 29°53′55″W / 68.91944°N 29.89861°W / 68.91944; -29.89861 (Island of Greenland) — most extensive island on Earth at 2,130,800 km2 (822,700 square miles) and tallest island of Western Hemisphere. Highest point is Gunnbjørn Fjeld at 12,118 feet (3,694 m).
Island of Cuba 21°30′N 80°0′W / 21.500°N 80.000°W / 21.500; -80.000 (Island of Cuba) — most extensive island of the Caribbean at 104,556 km2 (40,369 square miles). Highest point is Pico Turquino at convert 6,480 feet (1,980 m).
Hispaniola 19°1′23″N 70°59′53″W / 19.02306°N 70.99806°W / 19.02306; -70.99806 (Hispaniola) — tallest island of the Caribbean and second most extensive island of the Caribbean at 76,480 km2 (29,529 square miles). Highest peak is Pico Duarte at 10,417 ft (3,175 m).
Manitoulin Island in Lake Huron, Ontario, Canada 45°46′N 82°12′W / 45.767°N 82.200°W / 45.767; -82.200 (Manitoulin Island) — most extensive lake island on Earth at 2,766 km2 (1,068 square miles)
Unimak Island - highest point is Shishaldin Volcano at 9,373 ft (2,857 m).
Ellesmere Island - highest point is Barbeau Peak at 8,583 ft (2,616 m).
Jamaica - highest point is Blue Mountain Peak at 7,402 ft (2,256 m).
Axel Heiberg Island - highest point is Outlook Peak at 7,251 ft (2,210 m).
Vancouver Island - highest point is Golden Hinde at 7,211 ft (2,198 m).
Baffin Island - highest point is Mount Odin at 7,044 ft (2,147 m).
Umnak Island - highest point is Mount Vsevidof at 6,920 ft (2,110 m).
Unalaska Island - highest point is Makushin Volcano at 6,680 ft (2,040 m).

text: Lakes[edit]

text:
Lake Superior, Canada and the United States 47°45′N 87°30′W / 47.750°N 87.500°W / 47.750; -87.500 (Lake Superior) — most voluminous lake in Western Hemisphere at 11,600 km3 (2,800 cubic miles)
Great Slave Lake, Northwest Territories, Canada 61°40′N 114°00′W / 61.667°N 114.000°W / 61.667; -114.000 (Great Slave Lake) — deepest lake in Western Hemisphere at 614 m (2,014 feet)
Lake Michigan–Huron, Canada and the United States 45°49′N 84°45′W / 45.817°N 84.750°W / 45.817; -84.750 (Lake Michigan–Huron) — most extensive lake in Western Hemisphere and the most extensive fresh water lake on Earth at 117,702 km2 (45,445 square miles)
Nettilling Lake on Baffin Island, Nunavut, Canada 66°30′N 70°50′W / 66.500°N 70.833°W / 66.500; -70.833 (Nettilling Lake) — most extensive lake on an island on Earth at 5,066 km2 (1,956 square miles)
Great Salt Lake, Utah, United States 31°10′N 112°35′W / 31.167°N 112.583°W / 31.167; -112.583 (Great Salt Lake) — most extensive endorheic lake at 4,400 km2 (1,700 square miles)
Lake Manitou on Manitoulin Island in Lake Huron, Ontario, Canada 45°46′42″N 81°59′30″W / 45.77833°N 81.99167°W / 45.77833; -81.99167 (Lake Manitou) — most extensive lake on an island in a lake on Earth at 104 km2 (40 square miles)

text: Rivers[edit]

text:
Mississippi Basin, Canada and the United States 29°9′4″N 89°15′12″W / 29.15111°N 89.25333°W / 29.15111; -89.25333 (Mississippi River) — most extensive river basin at 2,981,076 km2 (1,151,000 square miles)
Mississippi-Missouri-Jefferson Rivers, United States 29°9′4″N 89°15′12″W / 29.15111°N 89.25333°W / 29.15111; -89.25333 (Mississippi-Missouri-Jefferson Rivers) — longest river system at 6,275 km (3,902 miles)
Missouri River, United States 38°48′49″N 90°7′11″W / 38.81361°N 90.11972°W / 38.81361; -90.11972 (Missouri River) — longest main stem river at 3,768 km (2,341 miles)
Mississippi River, United States 29°9′4″N 89°15′12″W / 29.15111°N 89.25333°W / 29.15111; -89.25333 (Mississippi River) — longest Gulf of Mexico main stem river at 3,544 km (2,202 miles)
Yukon River, Canada and the United States 62°35′55″N 164°47′40″W / 62.59861°N 164.79444°W / 62.59861; -164.79444 (Yukon River) — longest Bering Sea main stem river at 3,185 km (1,979 miles)
Nelson River, Manitoba, Canada 57°5′5″N 92°30′8″W / 57.08472°N 92.50222°W / 57.08472; -92.50222 (Nelson River) — longest Hudson Bay main stem river at 2,575 km (1,600 miles)
Colorado River, United States and Mexico 31°48′57″N 114°48′22″W / 31.81583°N 114.80611°W / 31.81583; -114.80611 (Colorado River) — longest Gulf of California main stem river at 2,330 km (1,450 miles)
Columbia River, Canada and the United States 46°14′39″N 124°3′29″W / 46.24417°N 124.05806°W / 46.24417; -124.05806 (Columbia River) — longest Pacific Ocean main stem river at 2,000 km (1,243 miles)
Mackenzie River, Northwest Territories, Canada 68°56′23″N 136°10′22″W / 68.93972°N 136.17278°W / 68.93972; -136.17278 (Mackenzie River) — longest Arctic Ocean main stem river at 1,738 km (1,080 miles)
Saint Lawrence River, United States and Canada 49°40′N 64°30′W / 49.667°N 64.500°W / 49.667; -64.500 (Saint Lawrence River) — longest Atlantic Ocean main stem river at 965 km (600 miles)

text: Extreme points of North American countries[edit]

text:
Extreme points of Canada
Extreme points of Cuba
Extreme points of Greenland
Extreme points of Mexico
Extreme points of the United States


document_title: Sunbeam Alpine

question_text: what kind of car in to catch a thief

question_tokens: what kind of car in to catch a thief

text: Sunbeam Alpine

text: Alpine Mark I and III[edit]

text:
Sunbeam Alpine Mark I & III

Alpine with factory aero-screens
registered November 1953

Overview

Production
1953–55
1.582 made[1]

Assembly
United Kingdom
Australia[2]

Body and chassis

Body style
2-door roadster

Related
Sunbeam-Talbot 90

Powertrain

Engine
2267 cc (2.3L) I4

Dimensions

Wheelbase
97.5 in (2,476 mm)[3]

Length
168.5 in (4,280 mm)[3]

Width
62.5 in (1,588 mm)[3]

Chronology

Successor
Series Alpine

tag: table

text: The Alpine was derived from the Sunbeam-Talbot 90 Saloon, and has become colloquially known as the "Talbot" Alpine. It was a two-seater sports roadster initially developed for a one-off rally car by Bournemouth Sunbeam-Talbot dealer George Hartnell.[1] It had its beginnings as a 1952 Sunbeam-Talbot drophead coupé. Announced in March 1953[4] it received its name following Sunbeam-Talbot saloons successes in the Alpine Rally during the early 1950s. On its first competitive outing, the July 1953 Coupe des Alpes, the new car won the Coupe des Dames (Sheila van Damm) and, without loss of any marks, four Coupes des Alpes driven by Stirling Moss, John Fitch, G Murray-Frame and Sheila van Damm.[5]

text: The car has a four-cylinder 2,267 cc (138.3 cu in) engine from the saloon, but with a raised compression ratio. However, since it was developed from the saloon platform, it suffered from rigidity compromises despite extra side members in the chassis. The gearbox ratios were changed, and from 1954 an overdrive unit became standard. The gearchange lever was column-mounted.[1] A true open 2-seater there were no external door handles or wind-up windows.

text:
Open two-seater (without wind-up windows)

1954

The Alpine Mark I and Mark III (no Mark II was made) were hand-built – as was the 90 drophead coupé – at Thrupp & Maberly coachbuilders from 1953 to 1955, and remained in production for only two years. Of the 1582 automobiles produced, 961 were exported to the USA and Canada, 445 stayed in the UK, and 175 went to other world markets. It has been estimated that perhaps as few as 200 have survived.[when?]
The Sunbeam Alpine Mk 1 Special: It was based on the 2267cc Mk 1 Sunbeam Talbot motor, with alloy rocker cover and Siamese exhaust ports [ cylinders 2 and 3 ]. These motors developed a reputed, 97.5 bhp at 4,500 rpm, mainly by raising the compression ratio to 8.0:1 and incorporating a special induction manifold with a twin choke Solex 40 P.I.I carburettor .
Sunbeam Alpine Team Cars : MKV 21 - 26: The motors were configured the same as the Sunbeam Alpine Mk I Special, with further tuning by ERA to raise power to 106 bhp.

text: Very few of these cars are ever seen on the big screen. However, a sapphire blue Alpine featured prominently in the 1955 Alfred Hitchcock film To Catch a Thief starring Cary Grant and Grace Kelly. More recently, the American PBS show History Detectives tried to verify that an Alpine roadster owned by a private individual was the actual car used in that movie. Although the Technicolor process could "hide" the car's true colour, and knowing that the car was shipped back from Monaco to the USA for use in front of a rear projection effect, the car shown on the programme was ultimately proven not to be the film car upon comparison of the vehicle identification numbers.

text: Alpine Series I to V[edit]

text:
Sunbeam Alpine Series I to V

Sunbeam Alpine Series IV

Overview

Production
1959–68
69,251 made[1]

Body and chassis

Body style
2-door roadster

Related
Sunbeam Tiger

Powertrain

Engine
Series I: 91.2 cu in (1.5 L) I4
Series II, III & IV—1592 cc (1.6L) I4
Series V—1725 cc (1.7L) I4

Dimensions

Wheelbase
86 in (2,184 mm)[3]

Length
155 in (3,937 mm)[3]

Width
61 in (1,549 mm)[3]

Height
51 in (1,295 mm)[6]

Chronology

Successor
none

text: The first open 2-seater Alpines were based on the Hillman 14 and its successor the Humber Hawk. Rootes replaced them with a softer new smaller 2-seater sports convertible coupé based on the current Hillman Minx and its variants. Kenneth Howes and Jeff Crompton were tasked with doing a complete redesign in 1956, with the goal of producing a dedicated sports car aimed principally at the US market. Ken Howes contributed some 80 per cent of the overall design work, he had worked at Ford before joining Rootes.

text: The Alpine was produced in four subsequent revisions until 1968. Total production numbered around 70,000. Production stopped shortly after the Chrysler takeover of the Rootes Group.

text: Series I 1959–60[edit]

text: The "Series" Alpine started production in 1959. One of the original prototypes still survives and was raced by British Touring car champion Bernard Unett.[7]

text: The car made extensive use of components from other Rootes Group vehicles and was built on a modified floorpan from the Hillman Husky estate car.[8] The running gear came mainly from the Sunbeam Rapier, but with front disc brakes replacing the saloon car's drums. An overdrive unit and wire wheels were optional. The suspension was independent at the front using coil springs and at the rear had a live axle and semi-elliptic springing. The Girling-manufactured brakes used 9.5 in (241 mm) discs at the front and 9 in (229 mm)drums at the rear.

text: Coupé versions of the post-1959 version were built by Thomas Harrington Ltd. After the Le Mans Index of Efficiency success of 1961, Harrington sold replicas as the "Harrington Le Mans", using a fastback body and an engine tuned to 104 hp (78 kW). Unlike the Le Mans racers, these cars had a more integrated rear roofline and were without the tail fins of the roadsters.[9] Until 1962 the car was assembled for Rootes by Armstrong Siddeley.[1]

text: An open car with overdrive was tested by the British magazine The Motor in 1959. It had a top speed of 99.5 mph (160.1 km/h) and could accelerate from 0–60 mph (97 km/h) in 13.6 seconds. A fuel consumption of 31.4 miles per imperial gallon (9.0 L/100 km; 26.1 mpg‑US) was recorded. The test car cost £1031 including taxes.[6]

text: 11,904 examples of the series I were produced.[1]

text: In 1960 Rootes Group marketed a limited-production three-door variant of the Alpine, marketed as a shooting brake. With leather interior and walnut trim, its price was double that of its open counterpart.[10]

text: The Series I used a 1,494 cc (91.2 cu in) engine and was styled by the Loewy Studios for the Rootes Group. It had dual downdraft carburetors, a soft top that could be hidden by special integral covers and the first available wind-up side windows offered in a British sports car of that time.

text: Series II 1960–63[edit]

text: The Series II of 1960[11] featured an enlarged 1,592 cc (97.1 cu in) engine producing 80 bhp and revised rear suspension, but there were few other changes. When it was replaced in 1963, 19,956 had been made.[1]

text: A Series II with hardtop and overdrive was tested by The Motor magazine in 1960, which recorded a top speed of 98.6 mph (158.7 km/h), acceleration from 0–60 mph (97 km/h) in 13.6 seconds and a fuel consumption of 31.0 miles per imperial gallon (9.1 L/100 km; 25.8 mpg‑US). The test car cost £1,110 including taxes.[12]

text: Series III 1963–64[edit]

text: The Series III was produced in open and removable hardtop versions. On the hardtop version the top could be removed and the soft-top was stored behind the small rear seat; also the 1592 cc engine was less powerful. To provide more room in the boot, twin fuel tanks in the rear wings were fitted. Quarter lights were fitted to the windows. Between 1963 and 1964, 5863 were made.[1]

text: Series IV 1964–65[edit]

text: There was no longer a lower-output engine option; the convertible and hardtop versions shared the same 82 bhp engine with single Solex carburettor. A new rear styling was introduced with the fins largely removed. Automatic transmission with floor-mounted control became an option, but was unpopular. From autumn 1964 a new manual gearbox with synchromesh on first gear was adopted in line with its use in other Rootes cars. A total of 12,406 were made.[1]

text: Series V 1965–68[edit]

text: The final version had a new five-bearing 1,725 cc (105.3 cu in) engine with twin Zenith-Stromberg semi-downdraught carburettors producing 93 bhp.[1] There was no longer an automatic transmission option. 19,122 were made.[1] In some export markets, 100 PS (99 bhp) SAE were claimed.[13]

text:
Sunbeam Alpine Series IV

1967 Sunbeam Alpine Series V

1967 Sunbeam Alpine Series V

text: A muscle-car variant of the later versions was also built, the Sunbeam Tiger.

text: Competition[edit]

text: The Alpine enjoyed relative success in European and North American competition. Probably the most notable international success was at Le Mans, where a Sunbeam Harrington won the Thermal Index of Efficiency in 1961.[9] In the United States the Alpine competed successfully in Sports Car Club of America (SCCA) events.

text: Vince Tamburo won the G-Production National Championship in 1960 using the 1494cc Series I Alpine. In 1961 Don Sesslar took 2nd in the F-Production National Championship followed by a 3rd in the Championship in 1962. For 1963 the Alpine was moved into E-Production facing stiff competition from a class dominated by the Porsche 356. Sesslar tied in points for the national championship while Norman Lamb won the Southwest Division Championship in his Alpine.

text: A championship for Don Sesslar finally was achieved in 1964 with 5 wins (the SCCA totaled the 5 top finishes for the year). Dan Carmichael won the Central Division Championship in 1964 and '65. Carmichael continued to race the Alpine until 1967, when he finished 2nd at the American Road Race of Champions.

text: Bernard Unett raced factory prototype Alpine (registration number XRW 302) from 1962 to 1964 and in 1964 won the Fredy Dixon challenge trophy, which was considered to be biggest prize on the British club circuit at the time. Unett went on to become British Touring car champion three times during the 1970s.[14]

text: A six-car works team was set up for the 1953 Alpine Rally. Although outwardly similar to their production-car counterparts they reputedly incorporated some 36 modifications, boosting the engine to an estimated 97.5 bhp.[15]

text: Alpine "Fastback"[edit]

text:
Sunbeam Alpine "Fastback"

Overview

Production
1969–75

Body and chassis

Body style
2-door fastback

Powertrain

Engine
1725 cc (1.7L) I4

Dimensions

Wheelbase
98.5 in (2,502 mm)[3]

Length
174.5 in (4,432 mm)[3]

Width
64.75 in (1,645 mm)[3]

Height
55 in (1,397 mm)[16]

Chronology

Successor
none

text: Rootes introduced the "Arrow" range in 1966, and by 1968 the saloons and estates (such as the Hillman Hunter) had been joined by a Sunbeam Rapier Fastback coupé model. In 1969, a cheaper, slightly slower and more economical version of the Rapier (still sold as a sporty model) was badged as the new Sunbeam Alpine.

text: All models featured the group's strong five-bearing 1725 cc engine, with the Alpine featuring a single Zenith-Stromberg CD150 carburettor to the Rapier's twins, and the Rapier H120's twin 40DCOE Weber carburettors.

text: Although drawing many parts from the group's "parts bin", including the rear lights of the estate Arrow models, the fastbacks nevertheless offered a number of unique features, including their pillar-less doors and rear side windows which combined to open up the car much like a cabriolet with a hardtop fitted. Extensive wooden dashboards were fitted to some models, and sports seats were available for a time.

text: Post-Sunbeam Alpine[edit]

text: The Alpine name was resurrected in 1976 by Chrysler (by then the owner of Rootes), on a totally unrelated vehicle: the UK-market version of the Simca 1307, a French-built family hatchback. The car was initially badged as the Chrysler Alpine, and then finally as the Talbot Alpine following Chrysler Europe's takeover by Peugeot in 1978. The name survived until 1984, although the design survived (with different names) until 1986.

text: Notable film and television appearances[edit]

text: This article contains embedded lists that may be poorly defined, unverified or indiscriminate. Please help to clean it up to meet Wikipedia's quality standards. Where appropriate, incorporate items into the main body of the article. (January 2015)

text:
A metallic blue 1953 Sunbeam Alpine Mk I is driven by Grace Kelly in To Catch a Thief (1955) with Cary Grant.
A Sunbeam Alpine Mk III is driven by Peggy Cummins in the film Night of the Demon (1957).
A red Series I Alpine is driven by Elizabeth Taylor in the film Butterfield 8 (1960) and features in a number of scenes.
A white Series 1 Alpine was the regular drive of Rod Taylor's character Glenn Evans, a crime fighting news reporter, in the early 1960s TV series, Hong Kong.
A lake blue "Series II" Alpine roadster is amongst the first on-screen "Bond cars" when it is rented and driven by James Bond in Dr. No of 1962, most notably in a scene where Bond drives it under a truck to escape from pursuing hit men. It was reportedly borrowed from a local resident, as the only suitable sports car available on the island used for filming.[17] In the novel, a Sunbeam Alpine was the chosen car of assassinated Secret Service agent John Strangways.
Michael Caine's character is rescued by a woman in a white 1968 Alpine roadster in the 1971 British crime film Get Carter. The car is later shunted into a dock with the owner locked in the boot.
A Sunbeam Tiger (the V8 version of the Alpine) was also the vehicle of choice for spy Maxwell Smart in the 1960s TV comedy series Get Smart. An Alpine, outfitted to look like the Tiger, was used for the "gadget" shots, such as the cannon that comes up through the bonnet. The Alpine was used because the cannon would not fit under the bonnet of a V-8 car. The car was modified by noted American customizer Gene Winfield and was the subject of a 1/25th scale plastic model kit.[18]
A similar Alpine is seen in the Arnold Schwarzenegger film Commando, where it was destroyed.[19][20]
A Sunbeam Alpine was driven by Imogen Stubbs in the 1990s British TV series Anna Lee.
A Sunbeam Alpine is driven by Michael Caine in the 1967 film Gambit. The film also starred Shirley MacLaine and Herbert Lom.
A powder blue 1967 Sunbeam Alpine is driven by Tuesday Weld and Anthony Perkins in the 1968 film "Pretty Poison".
In the TV series Heartbeat, the character of Jackie Bradley, portrayed by Fiona Dolman, drives a green hardtop Series V Sunbeam Alpine, with red interior, bearing the original registration plate LVY 666F (1967). In Series 11, episode 12, Closing the Book two characters arrive at Scripp's Garage in a gold, hardtop Sunbeam Alpine, bearing the registration plate 836 FXH.