The good news is sea level will not rise if Arctic melts. Your soft drink full of ice cubes does not overflow for same reason. Instead of the Northwest and Northeast Passages will become navigable by regular ships for part of the year very soon and feeds economic and military interests.
International shipping routes between Asia and Europe will be reduced by thousands of miles. Canada could face worldwide demands on opening the Passage for international transit. The implications in terms of increased ship traffic, pollution and infrastructure development regarding Arctic’s fragile ecosystems are obviously.
Each year the Arctic undergoes the seasonal formation in winter and in summer an area of ice the size of Europe melts away to freeze again the following winter - usually.
20th September 2007 - the National Ice and Snow Data Center announced a historical arctic sea ice minimum: A loss of 4.61 million square kilometer. That means some square meters per terrestrial - compared against the 20 year average minimum. Your greenhouse gas emissions do count!
Due to the positive ice-albedo feedback effect Arctic sea ice is a sensitive tipping point in the Earth climate system. Without that ice, heat energy from the ocean would be transferred to warm the polar air. In fact, sea ice is so effective an insulator that its absence would warm the overlying air by between 20 and 40°C during winter.
Last year the September minimum did not break the latest record, on the other hand it was just a matter of a few days. What can we expect for 2009? An important factor is the thickness of the sea ice. Scientists distinguish between annual and multi-annual ice. The latter is thicker and less vulnerable to sun rays, warmer sea water or air.
Based on submarine measurements, the ice draft is reported to have thinned by 40% from the 1960s and 1970s to the 1990s. Latest satellite based analysis show Arctic is now literally on thin ice. Thicker ice, which survives two or more years, now comprises just 10 percent of wintertime ice cover, down from 30 to 40 percent.
Personally, I think Climate Change is lacking a powerful symbol. CO2 is invisible, so what can we print on T-shirts? Although measurements and graphs state a yearly sea level rise of millimeters, a temperature increase of fractions of a degree and a few ppm of CO2 molecules - does someone feels the daily impact?
The vanishing Arctic may serve as a symbol, but climate models estimate the Arctic might be completely ice free in summer in 20 or 30 years. This would be an irreversible result of uncontrolled greenhouse gas emissions and a lack of political action and responsibility. Not all aspects of the Arctic are already modeled - possibly you can book a tourist trip to North Pole much earlier. Until then you may like the idea to see and prove how Global Warming is already changing our planet.
Two NASA satellites called Aqua and Terra capture daily photos of the poles on their orbit. The MODIS Rapid Response System at NASA/GSFC combines them into a daily mosaic of the Arctic since 18th April 2009. Since a few days the mosaic from the day before is available using the Explorer here with geoLink 1650.
More interactivity allows the spin-off side ice-map.appspot.com: seven daily updated maps, four zoom levels, a perma link feature and the calendar give you full access to the current melting season.
By default it starts with the latest complete mosaic of the Arctic. You can zoom in from a resolution of 4km to 500m meters per pixel (Ctrl-down/up) and see daily changes (Ctrl-left/right).
The tiles are downloaded and cropped on request, depending on the zoom level it may take some seconds or more until the picture is complete. But once all the tiles are processed and cached the interface is very responsive. The more users the better is the performance. Unfortunately the NASA near-realtime data feed experiences sometimes technical issues, a status page give latest information.
Very informative is the band 367 layer with a false color display. It includes an infra-red band and maps the wave lengths differently to the red, blue and green channels. Clouds, ice, water, land and vegetation are shown in different colors.
The photo on the right shows some dark red areas with melt water on the ice surface. In summer blue melt ponds will dot the surface of Greenland. If in late September there is no more red - all ice had disappeared.
For your convenience here are a few direct links:
Iceland (20/04/2009 - Band 367), Jakobshavn Glacier (24/04/2009 - Band 367), Bering Strait (06/05/2009), former Ellesmere Ice Shelf (02/05/2009), Nuuk (07/05/2009)
Did I mention Antarctica is also available? At least the outer regions are enjoying still a bit of sun light, but using the calendar you can go back and see an nearly intact Wilkins Ice Shelf (06/03/2009).
Follow Arctic sea ice changes on Twitter and discuss by using the comment function.
Many thanks to the whole MODIS Rapid Response team. Without their cooperation this project would not have been possible.
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