摘要
大部分结冰湖泊在封冻期的湖温都稳定维持在一定温度,而在青藏高原典型湖泊鄂陵湖2015-2016年观测到的湖温在冰期会出现持续上升现象,且这种现象普遍存在于整层水体,但目前出现这一现象的原因尚不明确。本文利用鄂陵湖站点观测数据和湖温观测数据、EnontekiöKilpisjärvi Kyläkeskus站点观测数据、MODIS地表温度数据、中国气象局降水数据和NCEP-DOE再分析资料评估了LAKE2.3模式在鄂陵湖的适用性,分析了局地气候特征和影响水体中辐射传输的主要物理参数对冰期湖温持续上升的影响。评估结果表明,LAKE2.3能够很好的模拟出鄂陵湖的温度变化及其内部的热力层结,特别是结冰期,模拟和观测的湖温廓线较为吻合。冰厚的模拟值较观测值偏小约30%,可能是由于岸边观测和一维模式的限制,无法模拟出由于三维动力作用而造成的湖冰在岸边堆积现象。敏感性实验结果显示,高原较强的向下短波辐射是造成鄂陵湖冰期湖温持续上升的主要气候因子,较大的风速使湖温上升幅度和速率增大,较小的向下长波辐射使冰期明显缩短。冰期湖温上升速率和幅度随着冰反照率和冰消光系数的增大而减小,无冰期较深层的湖温随着水消光系数的增大而减小。
The water temperature of most of the frozen lakes is stable at a certain value during the ice period.However,the water temperature of Ngoring Lake,a typical lake in the Qinghai-Xizang Plateau,will continue to rise during the ice period,and this phenomenon generally exists in the whole water body,but the reason for this phenomenon is still unclear.Based on station observation and lake temperature observation data in Ngoring Lake,EnontekiöKilpisjärvi Kyläkeskus station observation data,MODIS surface temperature data,China Meteorological Administration precipitation data and NCEP-DOE reanalysis data,the applicability of LAKE2.3 model in Ngoring lake was evaluated,and the influence of local climate characteristics and main physical parameters affecting radiation transmission in water body on the phenomenon is analyzed.The assessment results show that LAKE2.3 can well simulate the temperature change and thermal stratification in Ngoring lake,especially during the ice period,and the simulated and observed lake temperature profiles are relatively consistent.However,the simulated ice thickness is about 30%smaller than the observed value,which may be due to the limitation of shore observation and one-dimensional model that can’t simulate the lake ice accumulation phenomenon caused by three-dimensional dynamic action.The results of sensitivity experiments show that the strong downward shortwave radiation is the main climate factor that causes the continuous rise of water temperature in Ngoring Lake during the ice period.The larger wind speed further increases the rising range and speed of water temperature range and rate of the temperature rise,while the smaller downward long wave radiation shortens the ice duration.The rising rate and amplitude of lake temperature in ice period decrease when ice albedo and ice extinction coefficient increased,while the temperature of deep layer of the lake in ice free period decreases with the increase of water extinction coefficient.
作者
王梦晓
文莉娟
李照国
苏东生
WANG Mengxiao;WEN Lijuan;LI Zhaoguo;SU Dongsheng(Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions,Northwest Institute of Eco-Environment and Resources,Lanzhou 730000,Gansu,China;University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《高原气象》
CSCD
北大核心
2021年第5期965-976,共12页
Plateau Meteorology
基金
国家重点研发计划政府间国际科技创新合作项目(2019YFE0197600)
中德科学中心中德合作项目(GZ1259)
中科院“西部之光”计划西部青年学者A类项目(Y929641001)
中国科学院“西部之光”重点实验室交叉团队项目。
关键词
鄂陵湖
热力状况
冰厚
湖温上升现象
LAKE2.3模式
Ngoring Lake
thermal condition
ice thickness
the phenomenon of rising lake temperature
LAKE2.3 model
