Why do we care about Antarctic climate?

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Why do we care about Antarctic climate? A talk given by Andrew Russell at the north-west local centre of the Royal Meteorological Society on 29th March 2011

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Why do we care about Antarctic climate?

  1. 1. Why do we care about Antarctic climate? Dr Andrew Russell Brunel University [email_address] @dr_andy_russell @Antarctic_news
  2. 2. Antarctic talk <ul><li>Background (map, trivia, history) </li></ul><ul><li>The Antarctic ozone “hole” </li></ul><ul><li>Antarctic temperature and sea ice trends </li></ul><ul><li>Ice cores </li></ul><ul><li>Why I care about Antarctic climate i.e. my own research </li></ul><ul><li>Why you should care about Antarctic climate i.e. ice sheets and sea level rise </li></ul>
  3. 3. Image: BAS
  4. 4. Antarctic trivia <ul><li>Coldest continent – lowest recorded temperature is -89°C </li></ul><ul><li>Driest – strictly a desert (South Pole receives <10 cm per year, on average) </li></ul><ul><li>Windiest – the katabatic wind </li></ul><ul><li>Highest – ice up to 5km thick, average 1.6km across continent </li></ul><ul><li>Home to 90% of world’s ice </li></ul><ul><li>Population: 1000-5000 </li></ul>
  5. 5. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul>
  6. 6. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul>
  7. 7. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul>Wikipedia – image of 17 th Century Chinese map
  8. 8. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul>
  9. 9. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul>
  10. 10. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul><ul><li>1839: US expedition from Australia discovers Wilkes Land </li></ul>
  11. 11. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul><ul><li>1839: US expedition from Australia discovers Wilkes Land </li></ul><ul><li>1841: James Clark Ross passed through the Ross Sea and discovered Ross Island </li></ul>
  12. 12. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul><ul><li>1839: US expedition from Australia discovers Wilkes Land </li></ul><ul><li>1841: James Clark Ross passed through the Ross Sea and discovered Ross Island </li></ul><ul><li>1909: Mawson, David and Mackay (from Sir Ernest Shackleton's Nimrod Expedition) claimed to have found the South Magnetic Pole (72°S 155°E at that time) </li></ul>
  13. 13. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul><ul><li>1839: US expedition from Australia discovers Wilkes Land </li></ul><ul><li>1841: James Clark Ross passed through the Ross Sea and discovered Ross Island </li></ul><ul><li>1909: Mawson, David and Mackay (from Sir Ernest Shackleton's Nimrod Expedition) claimed to have found the South Magnetic Pole (72°S 155°E at that time) </li></ul><ul><li>1911: Roald Amundsen became the first to reach the geographic South Pole (14 Dec) </li></ul>
  14. 14. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul><ul><li>1839: US expedition from Australia discovers Wilkes Land </li></ul><ul><li>1841: James Clark Ross passed through the Ross Sea and discovered Ross Island </li></ul><ul><li>1909: Mawson, David and Mackay (from Sir Ernest Shackleton's Nimrod Expedition) claimed to have found the South Magnetic Pole (72°S 155°E at that time) </li></ul><ul><li>1911: Roald Amundsen became the first to reach the geographic South Pole (14 Dec) </li></ul><ul><li>1912: Scott reaches the pole </li></ul>
  15. 15. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul><ul><li>1839: US expedition from Australia discovers Wilkes Land </li></ul><ul><li>1841: James Clark Ross passed through the Ross Sea and discovered Ross Island </li></ul><ul><li>1909: Mawson, David and Mackay (from Sir Ernest Shackleton's Nimrod Expedition) claimed to have found the South Magnetic Pole (72°S 155°E at that time) </li></ul><ul><li>1911: Roald Amundsen became the first to reach the geographic South Pole (14 Dec) </li></ul><ul><li>1912: Scott reaches the pole </li></ul><ul><li>1914: Shackleton's Endurance expedition </li></ul>
  16. 16. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul><ul><li>1839: US expedition from Australia discovers Wilkes Land </li></ul><ul><li>1841: James Clark Ross passed through the Ross Sea and discovered Ross Island </li></ul><ul><li>1909: Mawson, David and Mackay (from Sir Ernest Shackleton's Nimrod Expedition) claimed to have found the South Magnetic Pole (72°S 155°E at that time) </li></ul><ul><li>1911: Roald Amundsen became the first to reach the geographic South Pole (14 Dec) </li></ul><ul><li>1912: Scott reaches the pole </li></ul><ul><li>1914: Shackleton's Endurance expedition </li></ul>Wikipedia
  17. 17. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul><ul><li>1839: US expedition from Australia discovers Wilkes Land </li></ul><ul><li>1841: James Clark Ross passed through the Ross Sea and discovered Ross Island </li></ul><ul><li>1909: Mawson, David and Mackay (from Sir Ernest Shackleton's Nimrod Expedition) claimed to have found the South Magnetic Pole (72°S 155°E at that time) </li></ul><ul><li>1911: Roald Amundsen became the first to reach the geographic South Pole (14 Dec) </li></ul><ul><li>1912: Scott reaches the pole </li></ul><ul><li>1914: Shackleton's Endurance expedition </li></ul><ul><li>1956: Halley Research Station and Amundsen-Scott South Pole Station founded </li></ul>
  18. 18. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul><ul><li>1839: US expedition from Australia discovers Wilkes Land </li></ul><ul><li>1841: James Clark Ross passed through the Ross Sea and discovered Ross Island </li></ul><ul><li>1909: Mawson, David and Mackay (from Sir Ernest Shackleton's Nimrod Expedition) claimed to have found the South Magnetic Pole (72°S 155°E at that time) </li></ul><ul><li>1911: Roald Amundsen became the first to reach the geographic South Pole (14 Dec) </li></ul><ul><li>1912: Scott reaches the pole </li></ul><ul><li>1914: Shackleton's Endurance expedition </li></ul><ul><li>1956: Halley Research Station and Amundsen-Scott South Pole Station founded </li></ul>
  19. 19. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul><ul><li>1839: US expedition from Australia discovers Wilkes Land </li></ul><ul><li>1841: James Clark Ross passed through the Ross Sea and discovered Ross Island </li></ul><ul><li>1909: Mawson, David and Mackay (from Sir Ernest Shackleton's Nimrod Expedition) claimed to have found the South Magnetic Pole (72°S 155°E at that time) </li></ul><ul><li>1911: Roald Amundsen became the first to reach the geographic South Pole (14 Dec) </li></ul><ul><li>1912: Scott reaches the pole </li></ul><ul><li>1914: Shackleton's Endurance expedition </li></ul><ul><li>1956: Halley Research Station and Amundsen-Scott South Pole Station founded </li></ul>
  20. 20. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul><ul><li>1839: US expedition from Australia discovers Wilkes Land </li></ul><ul><li>1841: James Clark Ross passed through the Ross Sea and discovered Ross Island </li></ul><ul><li>1909: Mawson, David and Mackay (from Sir Ernest Shackleton's Nimrod Expedition) claimed to have found the South Magnetic Pole (72°S 155°E at that time) </li></ul><ul><li>1911: Roald Amundsen became the first to reach the geographic South Pole (14 Dec) </li></ul><ul><li>1912: Scott reaches the pole </li></ul><ul><li>1914: Shackleton's Endurance expedition </li></ul><ul><li>1956: Halley Research Station and Amundsen-Scott South Pole Station founded </li></ul>
  21. 21. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul><ul><li>1839: US expedition from Australia discovers Wilkes Land </li></ul><ul><li>1841: James Clark Ross passed through the Ross Sea and discovered Ross Island </li></ul><ul><li>1909: Mawson, David and Mackay (from Sir Ernest Shackleton's Nimrod Expedition) claimed to have found the South Magnetic Pole (72°S 155°E at that time) </li></ul><ul><li>1911: Roald Amundsen became the first to reach the geographic South Pole (14 Dec) </li></ul><ul><li>1912: Scott reaches the pole </li></ul><ul><li>1914: Shackleton's Endurance expedition </li></ul><ul><li>1956: Halley Research Station and Amundsen-Scott South Pole Station founded </li></ul><ul><li>1957-1958: International Geophysical Year (IGY), suggested by leading scientists (including S. Fred Singer) in 1950, gave rise to year of Antarctic science </li></ul>
  22. 22. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul><ul><li>1839: US expedition from Australia discovers Wilkes Land </li></ul><ul><li>1841: James Clark Ross passed through the Ross Sea and discovered Ross Island </li></ul><ul><li>1909: Mawson, David and Mackay (from Sir Ernest Shackleton's Nimrod Expedition) claimed to have found the South Magnetic Pole (72°S 155°E at that time) </li></ul><ul><li>1911: Roald Amundsen became the first to reach the geographic South Pole (14 Dec) </li></ul><ul><li>1912: Scott reaches the pole </li></ul><ul><li>1914: Shackleton's Endurance expedition </li></ul><ul><li>1956: Halley Research Station and Amundsen-Scott South Pole Station founded </li></ul><ul><li>1957-1958: International Geophysical Year (IGY), suggested by leading scientists (including S. Fred Singer) in 1950, gave rise to year of Antarctic science </li></ul><ul><li>1959: Signing of the Antarctic Treaty (e.g. Article 1 – The area to be used for peaceful purposes only; military activity, such as weapons testing, is prohibited but military personnel and equipment may be used for scientific research or any other peaceful purpose) </li></ul>
  23. 23. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul><ul><li>1839: US expedition from Australia discovers Wilkes Land </li></ul><ul><li>1841: James Clark Ross passed through the Ross Sea and discovered Ross Island </li></ul><ul><li>1909: Mawson, David and Mackay (from Sir Ernest Shackleton's Nimrod Expedition) claimed to have found the South Magnetic Pole (72°S 155°E at that time) </li></ul><ul><li>1911: Roald Amundsen became the first to reach the geographic South Pole (14 Dec) </li></ul><ul><li>1912: Scott reaches the pole </li></ul><ul><li>1914: Shackleton's Endurance expedition </li></ul><ul><li>1956: Halley Research Station and Amundsen-Scott South Pole Station founded </li></ul><ul><li>1957-1958: International Geophysical Year (IGY), suggested by leading scientists (including S. Fred Singer) in 1950, gave rise to year of Antarctic science </li></ul><ul><li>1959: Signing of the Antarctic Treaty (e.g. Article 1 – The area to be used for peaceful purposes only; military activity, such as weapons testing, is prohibited but military personnel and equipment may be used for scientific research or any other peaceful purpose) </li></ul><ul><li>1985: Discovery of the Antarctic &quot;ozone hole&quot; by BAS </li></ul>
  24. 24. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul><ul><li>1839: US expedition from Australia discovers Wilkes Land </li></ul><ul><li>1841: James Clark Ross passed through the Ross Sea and discovered Ross Island </li></ul><ul><li>1909: Mawson, David and Mackay (from Sir Ernest Shackleton's Nimrod Expedition) claimed to have found the South Magnetic Pole (72°S 155°E at that time) </li></ul><ul><li>1911: Roald Amundsen became the first to reach the geographic South Pole (14 Dec) </li></ul><ul><li>1912: Scott reaches the pole </li></ul><ul><li>1914: Shackleton's Endurance expedition </li></ul><ul><li>1956: Halley Research Station and Amundsen-Scott South Pole Station founded </li></ul><ul><li>1957-1958: International Geophysical Year (IGY), suggested by leading scientists (including S. Fred Singer) in 1950, gave rise to year of Antarctic science </li></ul><ul><li>1959: Signing of the Antarctic Treaty (e.g. Article 1 – The area to be used for peaceful purposes only; military activity, such as weapons testing, is prohibited but military personnel and equipment may be used for scientific research or any other peaceful purpose) </li></ul><ul><li>1985: Discovery of the Antarctic &quot;ozone hole&quot; by BAS </li></ul><ul><li>2002: Larsen B ice shelf collapses </li></ul>
  25. 25. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul><ul><li>1839: US expedition from Australia discovers Wilkes Land </li></ul><ul><li>1841: James Clark Ross passed through the Ross Sea and discovered Ross Island </li></ul><ul><li>1909: Mawson, David and Mackay (from Sir Ernest Shackleton's Nimrod Expedition) claimed to have found the South Magnetic Pole (72°S 155°E at that time) </li></ul><ul><li>1911: Roald Amundsen became the first to reach the geographic South Pole (14 Dec) </li></ul><ul><li>1912: Scott reaches the pole </li></ul><ul><li>1914: Shackleton's Endurance expedition </li></ul><ul><li>1956: Halley Research Station and Amundsen-Scott South Pole Station founded </li></ul><ul><li>1957-1958: International Geophysical Year (IGY), suggested by leading scientists (including S. Fred Singer) in 1950, gave rise to year of Antarctic science </li></ul><ul><li>1959: Signing of the Antarctic Treaty (e.g. Article 1 – The area to be used for peaceful purposes only; military activity, such as weapons testing, is prohibited but military personnel and equipment may be used for scientific research or any other peaceful purpose) </li></ul><ul><li>1985: Discovery of the Antarctic &quot;ozone hole&quot; by BAS </li></ul><ul><li>2002: Larsen B ice shelf collapses </li></ul>
  26. 26. Antarctic history <ul><li>25 million years ago: Antarctica formed from the gradual break up of Gondwana </li></ul><ul><li>1st Century AD: Ptolemy suggested the idea to preserve the symmetry of known landmasses </li></ul><ul><li>1773: Cook came within 75 miles of Antarctica but retreated in the face of ice </li></ul><ul><li>1820: 1st confirmed sighting of Antarctica by the Russian expedition of von Bellingshausen and Lazarev (sighted twice more in 1820 by Bransfield and Palmer) </li></ul><ul><li>1839: US expedition from Australia discovers Wilkes Land </li></ul><ul><li>1841: James Clark Ross passed through the Ross Sea and discovered Ross Island </li></ul><ul><li>1909: Mawson, David and Mackay (from Sir Ernest Shackleton's Nimrod Expedition) claimed to have found the South Magnetic Pole (72°S 155°E at that time) </li></ul><ul><li>1911: Roald Amundsen became the first to reach the geographic South Pole (14 Dec) </li></ul><ul><li>1912: Scott reaches the pole </li></ul><ul><li>1914: Shackleton's Endurance expedition </li></ul><ul><li>1956: Halley Research Station and Amundsen-Scott South Pole Station founded </li></ul><ul><li>1957-1958: International Geophysical Year (IGY), suggested by leading scientists (including S. Fred Singer) in 1950, gave rise to year of Antarctic science </li></ul><ul><li>1959: Signing of the Antarctic Treaty (e.g. Article 1 – The area to be used for peaceful purposes only; military activity, such as weapons testing, is prohibited but military personnel and equipment may be used for scientific research or any other peaceful purpose) </li></ul><ul><li>1985: Discovery of the Antarctic &quot;ozone hole&quot; by BAS </li></ul><ul><li>2002: Larsen B ice shelf collapses </li></ul><ul><li>2004: Dome C ice core data (~800,000 years) published </li></ul>
  27. 27. What’s black and white and red all over?
  28. 28. Robert McCabe
  29. 29. The Antarctic “ozone hole”
  30. 30. Ozone depletion and “hole” <ul><li>CFCl 3 + hν -> CFCl 2 + Cl </li></ul><ul><li>Cl + O 3 -> ClO + O 2 </li></ul><ul><li>ClO + O 3 -> Cl + 2 O 2 </li></ul><ul><li>+ </li></ul><ul><li>chemical reactions on polar stratospheric clouds in the cold Antarctic stratosphere </li></ul><ul><li>= </li></ul>
  31. 31. Antarctic temperature trends
  32. 32. Is Antarctica warming, cooling or do we not really know?
  33. 33. Is Antarctica warming, cooling or do we not really know? Yes
  34. 34. Turner et al. (2005) “Antarctic climate change during the last 50 years” International Journal of Climatology 25 , 279-294.
  35. 35. Image: United States Historical Climatology Network
  36. 36. USA: 1000 observing stations, some go back to late 1800s Antarctica: 55 stations, very few go back to before 1957 Image: NASA
  37. 37. Can we be clever?
  38. 38. Steig et al. (2009) “Warming of the Antarctic ice-sheet surface since the 1957 International Geophysical Year” Nature 457 , 459-462.
  39. 39. O’Donnell et al. (2011). Improved methods for PCA-based reconstructions: case study using the Steig et al. (2009) Antarctic temperature reconstruction Journal of Climate , in press
  40. 40. Antarctic sea ice NSIDC Zhang (2004)
  41. 41. Antarctic sea ice <ul><li>Surface temperature increases </li></ul><ul><li>Upper ocean warms </li></ul><ul><li>Ice growth decreases </li></ul><ul><li>Decrease in salt rejection from new ice </li></ul><ul><li>Salinity of the upper ocean falls </li></ul><ul><li>Lower salinity and warmer water </li></ul><ul><li>Lower water density in the upper ocean </li></ul><ul><li>Fresher, less dense upper water </li></ul><ul><li>Increased stratification of ocean layers </li></ul><ul><li>Weaker convective overturning </li></ul><ul><li>Less ocean heat is transported upwards </li></ul><ul><li>Decrease in ice melting from ocean heat </li></ul><ul><li>Increase in net ice production </li></ul><ul><li>Sea ice increases </li></ul>skepticalscience.com
  42. 42. Antarctic ice cores
  43. 43. Bubbles and gases * V BAS
  44. 44. What period do ice cores cover?
  45. 45. Petit et al. (1999)
  46. 46. Tilt Eccentricity Precession Wikipedia IPCC
  47. 47. EPICA (2004) Nature
  48. 48. Phew! Wikipedia
  49. 49. But CO2 lags temperature in these records so how does this explain the warming?
  50. 50. Idea “borrowed” from Richard Alley. An analogy.. Initial credit card debt of £1000 Pay off £5 per month 20% APR interest Can an initial forcing be amplified by some other mechanism?
  51. 51. Idea “borrowed” from Richard Alley.
  52. 52. Not well understood but most likely some interplay of ocean processes like: <ul><li>ocean circulation </li></ul><ul><li>ocean temperature/salinity </li></ul><ul><li>marine biological activity </li></ul><ul><li>ocean-sediment interactions </li></ul><ul><li>seawater carbonate chemistry </li></ul><ul><li>air-sea exchange </li></ul>
  53. 53. My work on Antarctic weather and climate
  54. 55. Changes in the Southern Annular Mode IPCC (2007) IPCC (2007)
  55. 56. The Southern Annular Mode http://www.niwa.co.nz NIWA
  56. 57. The Southern Annular Mode http://www.niwa.co.nz
  57. 58. Negative SAM index
  58. 59. Positive SAM index
  59. 60. Changes in the Southern Annular Mode Gillett and Thompson (2003) Science Thompson and Solomon (2002) Science IPCC (2007) Marshall (2003)
  60. 62. Russell et al. (2008) ASL
  61. 63. Russell & McGregor (2010) Climatic Change Russell et al. (2004) Tellus A
  62. 70. Russell et al. (2006) GRL
  63. 72. http://nsidc.org/iceshelves/larsenb2002/animation.html
  64. 73. Southern Annular Mode BAS
  65. 74. Why you should be a bit concerned about Antarctic climate
  66. 75. IPCC (2007) Bindschadler et al. (1998) EoS “ Ice sheet models indicate that this would be offset by tens of percent by increased ice discharge, but still give a negative contribution to sea level, of –0.8 m by 3000 in one simulation with Antarctic warming of about 4.5°C ” Antarctic ice sheet
  67. 76. Rignot and Thomas (2002)
  68. 77. Peter Boyer Under the Antarctic ice sheet
  69. 78. Oppenheimer (1998) Nature Under the Antarctic ice sheet
  70. 79. Shepherd et al. (2001) Science Vaughan et al. (2006) GRL Pine Island Glacier
  71. 80. &quot;Parts of the Antarctic ice sheet that rest on bedrock below sea level have begun to discharge ice fast enough to make a significant contribution to sea level rise. Understanding the reason for this change is urgent in order to be able to predict how much ice may ultimately be discharged and over what timescale. Current computer models do not include the effect of liquid water on ice sheet sliding and flow, and so provide only conservative estimates of future behaviour.&quot; Chris Rapley, former director of BAS
  72. 81. 84m sea level rise! Benfield Hazard Research Centre. This plot is silly. Worse case scenario - complete WAIS collapse - would result in 4-6m of sea level rise.
  73. 82. Why you should be very interested in Antarctic climate
  74. 83. Ted Scambos
  75. 84. Manchester Science Festival 22-30 October 2011

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