高亚洲冰川区度日因子空间分布数据集

A dataset of spatial distribution of degree-day factors for glaciers in High Mountain Asia

基于冰雪消融与气温之间线性关系建立的度日模型是冰川研究中应用较为广泛的模型。度日因子是该模型的重要参数,反映了单位正积温产生的冰雪消融量,其空间变化对于该模型模拟冰雪消融过程的精度影响较大。然而,高亚洲地区有长期观测的冰川数量较少,无法为应用度日模型开展区域冰川消融模拟提供必要的参数。本研究基于高亚洲不同地区40余条冰川的考察和观测资料,构建了冰川冰与雪度日因子的转换公式,获取了高亚洲冰川区度日因子的空间分布格网数据集(GeoTIFF格式,32位浮点型),空间分辨率为0.5°,同时本数据精度已在典型区域的冰川物质平衡模拟应用中得到了验证。本数据集可为开展高亚洲区域冰川消融过程及其对水资源变化与相关灾害影响研究提供模型参数,为进一步分析高亚洲地区冰川变化与气候变化、水资源变化及其灾害效应提供必要的数据支撑。

The degree-day model,a widely used approach for ice and snow melt computation,rests upon a relationship between snow or ice melt and air temperature that is usually expressed in the form of positive temperature.The degree-day factor(DDF)is an important parameter for the model,and its spatial variation largely affects the accuracy of snow and ice melt simulations.Across High Mountain Asia(HMA),only a few glaciers have long-term observational records over the past decades,failing to provide necessary parameters for regional melting simulation based on degree-day models.In this study,we collected investigations and observations on 40 glaciers located in different regions of HMA,and estimated the transfer functions for snow and ice DDFs to obtain the dataset of spatial distributions of DDFs for snow and ice in HMA.These data,with a spatial resolution of 0.5°,were stored in GeoTIFF format in 32-bit floating point.Their accuracy is confirmed through a comparison between regional mass balance simulations using this dataset and observations in a typical region.The dataset provides model parameters for the study of regional glacier melting process and its impact on water resources and associated glacier disasters in HMA.It also provides data support for further analysis of glacier change and climate change,water resources change and its disaster effects in HMA.