Figure1. Credit: National Geographic
Declining sea ice is leading to an increase in sunlight reaching the upper layers of the ocean, setting off increased photosynthesis and greater production of phytoplankton, tiny marine plants which form the base of the food chain for fish and marine mammals. The timing of phytoplankton blooms throughout the Arctic Ocean is also being affected, with more frequent secondary blooms during the fall. In June, July and August 2014 the highest primary production - occurred in the Kara and Laptev seas north of Russia.
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Ⅰ. Thawing of permafrost Permafrost, a layer of soil that remains frozen throughout the year in high-latitude regions, currently holds about twice as much carbon as the atmosphere. As permafrost thaws under rapidly rising Arctic temperatures, microbes in the soil become more active, breaking down organic carbon and accelerating the release of carbon dioxide and methane into the air. These natural greenhouse gas emissions create even more climate warming. Figure2. As sea ice retreats in summer, more sunlight reaches
the upper layers of the sea, triggering increased blooms of phytoplankton such as here in the Bering Sea this fall. (Credit: NASA) |
Figure3. The polar jet stream can travel at speeds greater than 100 mph.
Here, the fastest winds are colored red; slower winds are blue. View animated version here. Credit: NASA/Goddard Space Flight Center |
Ⅲ. Jet Stream Increasing global warming is causing the glacial to melt during the summer, and the dark waters beneath the glacier expose to sunlight. It increases the absorption of solar radiation and causes the water to overheat during the summer, thereby accelerates the melting phenomenon. Excessive heat is discharged into the atmosphere, especially during the autumn reducing the temperature and atmospheric pressure gradients between the Arctic and mid-latitudes. Reduction in the pressure gradient along the latitude weakens the strength of the wind associated with the jet stream and the polar vortex. In the normal state, polar vortex makes the cold Arctic air masses to exist over the Arctic Circle, but when this gets weak, then cold air will invade the low latitude regions. This is the reason why the extreme cold occurs in the winter. |
References :
http://www.noaanews.noaa.gov/stories2014/20141217_arctic_report_card_2014.html
http://www.globalchange.gov/news/thawing-permafrost-slow-steady-emissions-likely
http://www.usgs.gov/newsroom/article.asp?ID=4185#.VVTUBPntmkq
Scientists Predict Gradual, Prolonged Permafrost Greenhouse Gas Emissions
U.S. Department of the Interior, U.S. Geological Survey
Office of Communications and Publishing
12201 Sunrise Valley Dr, MS 119
Reston, VA 20192
http://w1.weather.gov/glossary/index.php?letter=j
http://www.noaanews.noaa.gov/stories2014/20141217_arctic_report_card_2014.html
http://www.globalchange.gov/news/thawing-permafrost-slow-steady-emissions-likely
http://www.usgs.gov/newsroom/article.asp?ID=4185#.VVTUBPntmkq
Scientists Predict Gradual, Prolonged Permafrost Greenhouse Gas Emissions
U.S. Department of the Interior, U.S. Geological Survey
Office of Communications and Publishing
12201 Sunrise Valley Dr, MS 119
Reston, VA 20192
http://w1.weather.gov/glossary/index.php?letter=j