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利用现场观测与遥感数据对Lambert,Mellor和Fisher冰川的物质平衡及其在Amery冰架的底部融化与冻结状况进行了估算.结果表明,澳大利亚组织的Lambert冰川盆地(LGB)考察路线的上游地区,Lambert与Mellor冰川分别为(3.9±2.1)和(2.1±2.4)Gt·a-1的正平衡,而Fisher冰川基本处于平衡状态.上游地区总的正平衡为(5.9±4.9)Gt·a-1.考察路线以下,3条冰川均处于负平衡,总的负平衡为(-8.5±5.8)Gt·a-1.整个Lambert,Mellor和Fisher冰川均接近于平衡状态.3条冰川总净平衡为(-2.6±6.5)Gt·a-1.前人认为GL线(1970年代初澳大利亚在LGB建立的冰川运动观测点的连线)以上的内陆盆地处于显著正平衡,可能是因为过高地估算了总积累量,并低估了穿过GL线的冰通量.靠近Amery冰架南端着地线,冰架底部的平均融化速率为(-23.0±3.5)m冰·a-1,向下游方向快速减小,并在距冰架最南端约300km处过渡为底部冻结.沿3条冰川在Amery冰架的冰流带(flowband),冻结速率约介于(0.5±0.1)~(1.5±0.2)m冰·a-1.由于冰流带底部的融化,流入冰架的内陆冰损失了大约80%±5%.3条冰流带底部总融化和总冻结分别为(50.3±7.5)和(7.0±1.1)Gt冰·a-1,这要比前人通过模拟和海洋观测估算的整个Amery冰架底部总融化和总冻结还要大很多.
The physical balance of Lambert, Mellor and Fisher glaciers and their melting and freezing at the bottom of the Amery ice shelf were estimated using field observations and remote sensing data.The results show that the upper reaches of the Lambert Glacier Basin (LGB) The positive balance between the Lambert and Mellor glaciers is (3.9 ± 2.1) and (2.1 ± 2.4) Gt · a-1, respectively, while the Fisher glacier is basically in equilibrium. The total positive balance in the upper reaches is (5.9 ± 4.9) Gt · a- 1. Below the survey route, all three glaciers are in negative balance, with a total negative balance of (-8.5 ± 5.8) Gt · a-1. The Lambert, Mellor and Fisher glaciers are close to equilibrium. The total net balance of the three glaciers (-2.6 ± 6.5) Gt · a-1. It has been previously thought that the inland basins above the GL line (the connection of the glacier’s observation point established by the LGB in Australia in the early 1970s) are in a significantly positive balance, possibly because of the overbalanced The total accumulation was estimated and the ice flux through the GL line was underestimated.At the ground line to the southern end of the Amery ice shelf, the average melt rate at the bottom of the ice shelf was (-23.0 ± 3.5) m ice · a-1, The direction of rapid reduction, and the ice in the southernmost tip about 300km transition to the bottom of the frozen along the 3 glaciers in the Amery ice shelf (0.5 ± 0.1) ~ (1.5 ± 0.2) m ice · a-1 due to the melting of the bottom of the ice bank, the inland ice flowing into the ice shelf lost about 80 % ± 5%. The total melting and total freezing at the bottom of the three ice flow zones were (50.3 ± 7.5) and (7.0 ± 1.1) Gt ice · a-1, respectively, which was lower than that of the entire Amery estimated by simulation and ocean observations The bottom of the ice shelf always melts and the total freeze is still much larger.