The Ends of the Earth: Studying the Polar Regions

1. The Ends of the Earth: Studying the Polar Regions Guest Scientist: Michael Studinger Originally Presented 10 Nov 2007

2. We join in the IPY 2007 - 2008 • IGY—International Geophysical Year—1957 – 1958 • Sputnik, Van Allen Belts, exploration of Antarctica • Large-scale international cooperative investigations • International Polar Year 2007 - 2008

3. What is IPY? IPY Timeline IPY Draft Themes Education and Outreach IPY “Focus on …” Land Oceans Atmosphere Ice Space People http://www.ipy.org/

4. Satellite Studies of Polar Regions • Making accurate observations in polar regions is difficult and, for people, dangerous • So one of the most important advances during the last 50 years is use of satellite observation • Several polar-orbiting satellites with a variety of instruments routinely observe winds, ice, and other conditions

5. NASA’s Earth Observing System TERRA • “ASTER” Advanced Spaceborne Thermal Emission and Reflection Radiometer • “CERES” Clouds and the Earth's Radiant Energy System • “MODIS” Moderate-resolution Imaging Spectroradiometer Ross Ice Shelf, Antarctica http://veimages.gsfc.nasa.gov/245/MODIS1000029_md.jpg

6. “A Tour of the Cryosphere” NASA recently released an 8-minute multimedia DVD, which is also available on the Internet at http://www.nasa.gov/vision/earth/environment/cryosphere.html This provides a brief overview of some of the geographic and logistical challenges of working and living in polar regions.

7. Polar Aircraft Getting to and around Antarctica has posed logistical challenges that frequently have been met through specialized aircraft to operate in extreme conditions. Michael Studinger and colleagues have been involved in testing some of these. The Alfred Wegener Institute for Polar and Marine Research recently acquired new research capabilities.

8. Another LDEO Example • West Antarctica Ice Sheet Airborne Gravimetry

9. Even so, for those of us in the US and most of the Northern Hemisphere, the Southern Hemisphere is largely “Terra Incognito” We can look at maps and see shapes and unfamiliar names. But we tend to think of the Southern Ocean and surrounding land masses merely as the bottom half of maps or globes. New techniques are beginning to allow us to show more about this interesting portion of our planet: http://www.ngdc.noaa.gov/mgg/image/predict.gif

10. http://tea.armadaproject.org/activity/demello/ICE_CONTINENT_ENCOUNTER.doc#AntarcticMapshttp://tea.armadaproject.org/activity/demello/ICE_CONTINENT_ENCOUNTER.doc#AntarcticMaps

11. In previous E2C Workshops, Dr. Michael Studinger shared his research into how we can study features hidden beneath the ice sheets of Antarctica • You can find links to these from the E2C website. • This year, Michael will discuss some of the contributions he and other LDEO scientists are making toward IPY 2007 – 2008.

12. Some More Useful Background Information:The most important feature about Antarctica is that it is now very cold! Located at Earth’s southern pole means that little or no solar energy is received during half the year, and although the sun shines for long day lengths in the other half, not much energy is absorbed

13. But it wasn’t always this way! • 200 mya, what was to become Antarctica was at the center of Gondwanaland, the southern supercontinent created as Pangaea began to split apart • It was connected to Australia, Africa, South America, India, and New Zealand • Fossils provide evidence that climate was much warmer and lush vegetation covered much of the surface • Any polar ice cap was much smaller, so sea level was much higher

14. Becoming Antarctica • Formation of the Circumpolar Current (West Wind Drift) played a major role in isolating and cooling Antarctica • Changes in ocean circulation had major effects on energy transfer on the globe, which will explored in the next few slides • Consequently, the ice cap grew and sea level was lowered, and Antarctica became “Earth’s ice box”

15. You can study an animation from a PBS “NOVA” program showing the breakup of Gondwanaland at http://www.pbs.org/wgbh/nova/eden/media/stt.html

16. Modern Antarctica results largely from its isolation at the pole and the ocean currents that surround it. http://www.windows.ucar.edu/tour/link=/earth/Water/images/Surface_currents_jpg_image.html

17. What did you notice abut these currents? • The Southern Ocean is the only area of the world with flow uninterrupted by land • The general movement is west-to-east • There are connections with other surface currents to the north and poleward • These involve both wind-driven surface currents and density-driven deeper circulations

18. Connections between Surface and Deep-Sea Currents In the past few years, greater under-standings have developed concerning the elaborate interactions between the wind-driven surface patterns and the thermo-haline (temperature and salinity) deeper flows. One model of this is the “Ocean Conveyor Belt, depicted in the next slide:

19. http://www.grida.no/climate/vital/32.htm

20. Much attention has been given to this model, especially speculations about what might happen if it changes LDEO’s Wally Broecker, who helped devise this model, recently considered the impact on climate that might ensue if the conveyor belt slowed or stopped http://faculty.washington.edu/wcalvin/teaching/Broecker99.html

21. So the circulation patterns around Antarctica play major roles in global air-sea exchanges http://www.glacier.rice.edu/oceans/4_antsurfwater.html

22. What lies on land beneath Antarctica’s Icecap? http://www.earthinstitute.columbia.edu/news/story3_2_01.html

23. Probing Beneath the Ice Cap Between 1988 – 1997, NASA’s RADARSAT program studied our planet using SAR (Synthetic Aperture Radar) techniques. NASA’s Scientific Visualization Studio has created an animation using these data.

24. And what does Lake Vostok look like? From the surface, nothing that would indicate there’s an interesting lake can be seen In fact, more than 70 subglacial lakes have been identified by remote sensing http://www.earthinstitute.columbia.edu/news/story3_2_01a.html

25. Lake Vostok Animation LDEO scientists Robin Bell, Michael Studinger, and colleagues have created this animation about Lake Vostok: http://www.earthinstitute.columbia.edu/news/vostok/vostok.swf

26. Life Under Extreme Conditions • One of the major reasons to study Lake Vostok is that it is possible that bacteria and other microbes may exist under the ice in vast extreme ecosystems. • Understanding how these extremophiles exist may be vital to studying possible lifeforms elsewhere, especially Europa, the frozen moon of Jupiter

27. Antarctic seas also teem with interesting lifeforms and ecosystems Dr. Sam Bowser was the 2003 Keynote Speaker at the 108th STANYS Conference Dr. Bowser’s research about foraminifer and other life in Antarctic waters is available at http://members.global2000.net/bowser/

28. LDEO’s contributions to IPY LDEO research scientists are actively involved in several IPY programs, as Michael Studinger will discuss in his portion of this E2C Workshop. Next month, Trevor Williams will continue this theme with his account of ANDRILL, the Antarctic Drilling Project. We also expect to have a live teleconference with Louise Huffman, a Teacher-in-Antarctica with ANDRILL and School of Rocker. Y’all come back, y’hear!