中国西部雪冰中的黑碳及其辐射强迫

Black Carbon in Snow/Ice of West China and Its Radiative Forcing

在中国西部的青藏高原和新疆地区的若干条冰川区域采集雪和冰芯样品,分析了雪冰样品中的黑碳,并模拟了雪冰黑碳产生的辐射强迫。我国西部雪冰黑碳的平均浓度为63ng/g,高于北半球其他地区的实测结果。影响雪样黑碳浓度空间分布格局的主因是周边的排放源。模拟结果显示,黑碳在中国西部冰川雪表的沉降产生的平均辐射强迫为(+4.0±2.0)W/m2。喜马拉雅山中段的东绒布冰芯记录揭示黑碳主要来源于南亚,经印度夏季风输送;1951年以来黑碳的平均浓度为16ng/g,产生的月平均辐射强迫在2001年夏季超过了+4.5W/m2。南亚排放的黑碳可能抵达青藏高原南部腹地,对青藏高原的冰川表面能量平衡有一定影响。

Snow and ice core samples were collected from the glaciers located in the Tibetan Plateau （TP） and Xinjiang of west China. Black carbon （BC） was measured and its radiative forcing after deposition in snow was simulated. The average BC concentration in the snow of west China was about 63 ng/g, higher than the other measurements in the Northern Hemisphere; and its spatial distribution was primarily affected by surrounding emissions. Simulated mean radiative forcing caused by BC deposits in snow was about （＋4.0 ± 2.0） W/m^2. An ice core （aged 1951-2001） drilled in the middle Himalayas and transport analysis shows that black carbon was primarily transported from South Asia by Indian summer monsoon, causing a forcing over 4.5 W/m^2 in the summer of 2001. BC emitted from South Asia could penetrate into the inland of TP and might have significant effects on the surface energy balance of the glaciers in the TP.