1 / 52

Impacts of a Disappearing Arctic Sea Ice Cover

Impacts of a Disappearing Arctic Sea Ice Cover. Peter Wadhams Professor of Ocean Physics Department of Applied Mathematics and Theoretical Physics University of Cambridge Cambridge Society for the Application of Research, 15 October 2012. The Earth is warming rapidly….

evangeline-byrd
Download Presentation

Impacts of a Disappearing Arctic Sea Ice Cover

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Impacts of a Disappearing Arctic Sea Ice Cover Peter Wadhams Professor of Ocean Physics Department of Applied Mathematics and Theoretical Physics University of Cambridge Cambridge Society for the Application of Research, 15 October 2012

  2. The Earth is warming rapidly…

  3. SSG Copenhagen 24-5-07

  4. Arctic ice is disappearing in summer….

  5. Record minimum ice extent in Sept. 2007 2005

  6. Ice drift summer 2007 Aug/Sept 2007

  7. Fitting multibeam to a submarine – Kongsberg EM3002 on HMS “Tireless” March 2007, Arctic Ocean transect EM3002 multibeam sonarin forward sonar dome

  8. Submarine track

  9. UK submarine cruises in Greenland Sea prior to 2007

  10. Example of multiyear ridge intersected by refrozen lead – note poorer resolution than AUV due to greater depth (120 m) and speed of vehicle. But longer range (2000 km of data).

  11. First use of a through-ice AUV – Gavia plus Geoswath sonar from APLIS 2007 ice camp in Beaufort Sea. Vehicle operated under first-year ridge (foreground) from black and red hut (background)

  12. Working hut (right) and 3-man sleeping hut (left) in field of multi-year ridging

  13. A nearby multiyear ridge (left back) showing very solid smoothed ice blocks intersected by leads. Isolated pinnacles in first year ice in foreground. Figure 2. Sonar swath west of the deployment.

  14. High-resolution multibeam of the first-year ridge. Detail in red is genuine resolution of small broken ice blocks (see diver photo)

  15. Mean drafts from April 2004(Initial Processing) Contour maps of mean ice drafts from Eurasian Basin, October 1976 and May 1987 (Wadhams, Nature, 1990)

  16. SSG Copenhagen 24-5-07

  17. Changing MY fraction (Kwok et al, 2009)

  18. retreat of sea ice from around Greenland speeds summer melt, accelerating sea level rise

  19. b SSG Copenhagen 24-5-07

  20. BUT… exposure of the shelves leads to permafrost melt and methane release, both offshore and on land Canada Alpha-Mendeleev Ridge Greenland Russia Lomonosov Ridge SSG Copenhagen 24-5-07

  21. Oil exploration will be easier

  22. …and will extend into areas previously considered too hostile, like the NE Greenland shelf

  23. Conclusions • So long as carbon emissions continue to increase, global warming will continue to develop. • Even if carbon emissions were to stop entirely, there would still be some continued warming for several decades. • If present trends continue, average warming at low latitudes will be about 4°C by end of 21st Century. • Multiply this by 2-4 for high latitudes. • This will be accompanied by GLOBAL SEA LEVEL RISE (about 1 m in century); LOWER PRECIPITATION in key tropical regions leading to desertification, reduced food production, and loss of rain forest • Possible surprises: methane boost from permafrost melt causing short term acceleration of warming, other effects not yet spotted (cf. ocean acidification).

More Related