为了探讨VIC(Variable infiltration capacity)水文模型在季节性冻土区水文模拟中的适用性，以大凌河复兴堡站以上流域为研究区，构建了考虑能量平衡模式的VIC大尺度水文模型，评价了VIC模型在东北季节性冻土区水文模拟的适用性，并对不考虑能量平衡模式的水文模拟进行了比较分析。结果表明，考虑能量平衡模式的VIC模型率定期和验证期径流模拟效率系数在0.63以上，相对误差在6.0%以内。与不考虑能量平衡模式的水文过程模拟差异性比较显示，考虑了能量平衡模式的VIC模型可以更好地刻画由于冻土冻融过程引起的径流变化特征，模拟的土壤含水量和蒸散发量的空间分布特征更加合理。

Future changes of pan-Arctic land-atmospheric methane (CH4) and carbon dioxide (CO2) depend on how terrestrial ecosystems respond to warming climate. Here, we used a coupled hydrology-biogeochemistry model to make our estimates of these carbon exchanges with two contrasting climate change scenarios (no-policy versus policy) over the 21st century, by considering (1) a detailed water table dynamics and (2) a permafrost-thawing effect. Our simulations indicate that, under present climate conditions, pan-Arctic terrestrial ecosystems act as a net greenhouse gas (GHG) sink of -0.2 Pg CO2-eq.yr(-1), as a result of a CH4 source (53 Tg CH4 yr(-1)) and a CO2 sink (-0.4 Pg C yr(-1)). In response to warming climate, both CH4 emissions and CO2 uptakes are projected to increase over the century, but the increasing rates largely depend on the climate change scenario. Under the non-policy scenario, the CH4 source and CO2 sink are projected to increase by 60% and 75% by 2100, respectively, while the GHG sink does not show a significant trend. Thawing permafrost has a small effect on GHG sink under the policy scenario; however, under the no-policy scenario, about two thirds of the accumulated GHG sink over the 21st century has been offset by the carbon losses as CH4 and CO2 from thawing permafrost. Over the century, nearly all CO2-induced GHG sink through photosynthesis has been undone by CH4-induced GHG source. This study indicates that increasing active layer depth significantly affects soil carbon decomposition in response to future climate change. The methane emissions considering more detailed water table dynamics continuously play an important role in affecting regional radiative forcing in the pan-Arctic.