| Based on AMSR sea ice concentration data from2003to2013, this paper analyzes thechanges of the Arctic sea ice in distribution, change of concentration, regulations of areaand extent, condition of one-year and perennial ice, the summer sea ice of2003to2013,finding out that it is obvious regional, seasonal, inter-annual different and hysteretic.(1)The results show that the arctic sea ice in the summer has high intensity center on theNorth Pole, sea ice intensity from the north to the south gradually reduces, most of thearea is covered by sea ice in north of80°N, which concentration is above95%.If thearctic is divided into four areas, the study found that the distribution of sea ice Area1isthe most extensive; many islands situated in Area2, which impedes the sea ice move, inorder to virtually no change except the Baffin bay and the Greenland sea; Area3hasopen waters, contributing to melt and move, sea ice changing obviously; Area4is thearctic ocean blocking by Asian continent leading to more heat transportation to sea inthe summer, large amount of sea ice melting. If only into two areas, the number anddistribution of the Pacific area is always more than the other zone on the side of theAtlantic. Although the condition and change differ in each area, in general, closing tothe mainland or connecting to the open waters changes even more significant.(2)It has obvious difference in four seasons of sea ice concentration, number, extent andchange trend. The average sea ice intensity is biggest in winter while is smaller in springand smallest in summer. The area and extent reach to minimum:5.05×106km2,5.86×106km2in summer, which are most in winter. The total extent of the Arctic sea icedecreases the most rapidly in summer, while the speed reduces less quickly in autumnand lest in winter and spring.(3) Arctic ice is most serious in2003,2004,2005,2006,2009, when the area and extentare larger, while in2007,2011and2012, the arctic sea ice is relatively less. From2003to2013, sea ice area and extent reduce by0.10×106km2,0.11×106km2. It shows a trendof decrease in the nearly10years by0.14×106km2,0.14×106km2annually. Overall,the arctic sea ice area has similar change speed to extent.(4)Arctic sea ice maxmum value appears in March:10.07×106km2,10.37×106km2, andthe smallest annual average temperature in Sepember:4.16×106km2,4.82×106km2. Arctic sea ice minimum value appears in September, and the biggest annual averagetemperature in March. So changes in sea ice have a lag for there is energy accumulatedprocess.(5)The multiyear ice has high concentration in more than90%, locating in north of80°N. On average, one-year ice increases0.09×106km2annually, and Multi-year icereduces0.16×106km2year by yeae. For the increasing speed quick than decreasing, thetotal number is less and less. In addition, the change trend of a single month, July,August and September and the changes in the overall summer is extremely similar, allperforming decreasing trends, reducing the fastest in September by0.15×106km2, mostslow in August, decreasing by0.12×106km2. |
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