Ice‐Covered Lakes of Tibetan Plateau as Solar Heat Collectors
Ice‐Covered Lakes of Tibetan Plateau as Solar Heat Collectors
复制标题
DOI：
10.1029/2021gl093429
复制
发表时间：
2021-07
影响因子：
5.2
通讯作者：
G. Kirillin;T. Shatwell;L. Wen
中科院分区：
文献类型：
--
作者：
G. Kirillin;T. Shatwell;L. Wen
青藏高原拥有世界上最大的高寒湖泊系统，在陆气相互作用中起着至关重要的作用。我们首次报道了对高原最大淡水湖冰下热量和辐射状况的观测。结果表明，青藏高原淡水湖在冰下充分混合。由于强烈的太阳加热，在冰破裂前1-2个月，水的温度上升到最大密度值以上，形成稳定的热层结，其地下温度为>；6°C。由此产生的从水到冰的热流对冰盖融化做出了关键贡献。冰破裂后，累积的热量在1-2天内被释放到大气中，使湖-大气热通量增加到500W m−2。深对流混合的直接生物地球化学后果是深水湖水的充气和营养物质向上供应到上层光层。
The Qinghai‐Tibet Plateau possesses the largest alpine lake system, which plays a crucial role in the land‐atmosphere interaction. We report first observations on the thermal and radiation regime under ice of the largest freshwater lake of the Plateau. The results reveal that freshwater lakes on the Tibetan Plateau fully mix under ice. Due to strong solar heating, water temperatures increase above the maximum density value 1–2 months before the ice break, forming stable thermal stratification with subsurface temperatures >6°C. The resulting heat flow from water to ice makes a crucial contribution to ice cover melt. After the ice breakup, the accumulated heat is released into the atmosphere during 1–2 days, increasing lake‐atmosphere heat fluxes up to 500 W m−2. The direct biogeochemical consequences of the deep convective mixing are aeration of the deep lake waters and upward supply of nutrients to the upper photic layer.