Re-measurement of microparticle content of surface 10 m ice core from the top of King George Island Ice Cap shows that, except samples in 8. 5～ 10 m depth, the microparticle content generally decreases 45%～ 85% with...Re-measurement of microparticle content of surface 10 m ice core from the top of King George Island Ice Cap shows that, except samples in 8. 5～ 10 m depth, the microparticle content generally decreases 45%～ 85% within first 48 hours at melted state, afterwards, the content change is small. Content at each grain size interval has a decrease, but the main decrease is in particles of <3μm. Though particle content varies with depth, the decreases are much larger in peak areas than in valleys. From the tests, it can be considered that, the reason of particle content decrease at melted state is that some sea salt grains in samples dissolved. The microparticle content of samples in 8. 5～ 10 m depth has not decrease, the reason is that melting and re freezing have occurred at the depth, because the ice temperature is near 0 °C, and there are series of ice layers, the thickest is 7 cm, at that depth. The chemical analyses for same samples at same conditions show that, except irregular changes in NH4,NO, there are small changes in other ions, probably the content changes in micro-grain <3 μm can not obviously cause the chemical content change in samples.展开更多
During the Austral summer of 1996/1997, the First Chinese Antarctic Inland Expedition reached the inland area about 330 km along the direction around 76°E from Zhongshan Station, and collected 84 surface snow...During the Austral summer of 1996/1997, the First Chinese Antarctic Inland Expedition reached the inland area about 330 km along the direction around 76°E from Zhongshan Station, and collected 84 surface snow samples at an interval of 4 km . Micro particle analysis of the samples indicates that the micro particle concentration apparently decreases with the increasing of altitude, and the amplitudes of micro particle concentration is much larger in the lower altitude than in the higher altitude. Further analysis of grain size distributions of micro particle, percentage of micro particles from different sources and variations with altitude suggest that micro particles in this area are from a considerably dominant source. Although this area is controlled by polar easterly wind and katabatic wind, transportation and deposition of the micro particles are mainly influenced by marine transportation in coastal area.展开更多
文摘Re-measurement of microparticle content of surface 10 m ice core from the top of King George Island Ice Cap shows that, except samples in 8. 5～ 10 m depth, the microparticle content generally decreases 45%～ 85% within first 48 hours at melted state, afterwards, the content change is small. Content at each grain size interval has a decrease, but the main decrease is in particles of <3μm. Though particle content varies with depth, the decreases are much larger in peak areas than in valleys. From the tests, it can be considered that, the reason of particle content decrease at melted state is that some sea salt grains in samples dissolved. The microparticle content of samples in 8. 5～ 10 m depth has not decrease, the reason is that melting and re freezing have occurred at the depth, because the ice temperature is near 0 °C, and there are series of ice layers, the thickest is 7 cm, at that depth. The chemical analyses for same samples at same conditions show that, except irregular changes in NH4,NO, there are small changes in other ions, probably the content changes in micro-grain <3 μm can not obviously cause the chemical content change in samples.
文摘During the Austral summer of 1996/1997, the First Chinese Antarctic Inland Expedition reached the inland area about 330 km along the direction around 76°E from Zhongshan Station, and collected 84 surface snow samples at an interval of 4 km . Micro particle analysis of the samples indicates that the micro particle concentration apparently decreases with the increasing of altitude, and the amplitudes of micro particle concentration is much larger in the lower altitude than in the higher altitude. Further analysis of grain size distributions of micro particle, percentage of micro particles from different sources and variations with altitude suggest that micro particles in this area are from a considerably dominant source. Although this area is controlled by polar easterly wind and katabatic wind, transportation and deposition of the micro particles are mainly influenced by marine transportation in coastal area.
