黑碳对北冰洋积雪和海冰影响的模拟研究

Simulation of the impact of black carbon on snow and sea ice in the Arctic Ocean

当黑碳沉降到冰雪表面时,可使冰雪表面反照率降低,对短波辐射的吸收增加,黑碳的变化对海冰融化过程的影响值得研究。本文利用CICE海冰模式进行数值模拟,并定量分析北冰洋冰雪中黑碳造成的影响。研究表明,在不同黑碳数据源的强迫下,1980-2014年间,模拟结果给出的夏季北冰洋反照率平均下降为0.82%~1.71%,最终造成海冰面积下降了0.97%~1.93%,而在巴伦支海、喀拉海以及拉普捷夫海,夏季黑碳造成的海冰面积下降约为北冰洋整体的2-3倍。不同黑碳沉降强迫下的模拟结果均显示,1980-1995年,北冰洋区域黑碳对反照率的影响呈现减小趋势,但在1996-2014年,黑碳影响转为增加趋势。在低纬度海区,由于海冰的消退,黑碳的辐射效应呈现减小趋势,而在高纬度海区,由于多年冰内黑碳的累积效应,黑碳的辐射影响呈现增强效应。

When black carbon deposits on snow/ice surface,it can reduce the albedo and increase the absorption of shortwave radiation.The changes in black carbon and their impact on the sea ice melting process are worth investigating.Study of the influence of black carbon in the Arctic Ocean was conducted using the CICE sea ice model.The results indicates that under the impact of black carbon deposition from different sources,from 1980 to 2014,the simulated summer albedo of the Arctic Ocean decreased by 0.82%to 1.71%,ultimately causing a decrease in sea ice extent by 0.97%−1.93%.In the Barents Sea,Kara Sea,and Laptev Sea,the summer sea ice area reduction caused by black carbon is approximately 2–3 times greater than the overall reduction in the Arctic Ocean.The simulation results under different black carbon deposition all show that from 1980 to 1995,the impact of black carbon on albedo in the Arctic exhibited a decreasing trend.However,from 1996 to 2014,the black carbon effect shifted to an increasing trend.In low-latitude regions,due to the retreat of sea ice,the effect of black carbon showed a decreasing trend,while in high-latitude regions,due to the cumulative effect of black carbon in multi-year ice,the radiative impact of black carbon showed an enhancing effect.