中国MODIS逐日无云500m积雪面积产品数据集（2000-2020年）

积雪是冰冻圈重要的组成部分，积雪覆盖范围影响地气能量平衡，进而影响气候和环境变化。积雪面积是重要的积雪参数之一，是水文和气候模型的重要输入。本数据集针对中国积雪特性，基于MODIS反射率产品MOD/MYD09GA，利用不同土地覆盖类型条件下发展了多指数结合积雪判别算法，提高了林区和山区积雪面积精度，同时利用隐马尔科夫算法、多源数据融合方法实现了产品的完全去云，制备2000-2020年空间分辨率为500m的逐日无云积雪面积数据集。该数据集以HDF5文件格式存储，每个HDF5文件包含18个数据要素，其中包括数据值（0=陆地，1=影像识别积雪， 2=去云插补积雪，3=雪深插补积雪，4=水体，255=填充值）、数据起始日期、经纬度等。同时为了快速预览积雪分布情况，逐日文件包含积雪面积缩略图，以jpg格式存储。此外本数据集还包含了用户使用手册。本数据集采用完全开放共享。

Snow cover is an important component of the cryosphere. The extent of snow cover affects the atmosphere-land energy balance, which further influences climate and environmental changes. Snow cover area is one of the key snow parameters, serving as a critical input for hydrological and climate models. This dataset is tailored to the snow cover characteristics of China, based on the MODIS reflectance product MOD/MYD09GA. It develops a multi-index combined snow discrimination algorithm considering different land cover types, which improves the accuracy of snow cover area mapping in forested and mountainous regions. Meanwhile, it adopts the Hidden Markov Model (HMM) and multi-source data fusion methods to achieve complete cloud removal for the product, and compiles a daily cloud-free snow cover area dataset spanning 2000 to 2020 with a spatial resolution of 500 meters. This dataset is stored in HDF5 file format, and each HDF5 file contains 18 data fields, including data values (0 = land, 1 = snow identified from imagery, 2 = snow via cloud-removed interpolation, 3 = snow via snow depth interpolation, 4 = water body, 255 = fill value), data start date, latitude and longitude coordinates, etc. Additionally, to enable quick preview of snow cover distribution, each daily file includes a snow cover area thumbnail stored in JPG format. In addition, this dataset also provides a user manual. This dataset is fully open and publicly shared.

搜集汇总

背景与挑战

背景概述

该数据集是中国陆域2000-2020年逐日无云积雪面积产品，空间分辨率为500米，基于MODIS反射率数据开发，采用多指数结合算法和隐马尔科夫去云方法，提高了积雪面积在复杂地形区的精度。数据以HDF5格式存储，包含积雪分类、日期和经纬度等信息，适用于水文、气候模型及冰冻圈研究，并支持开放共享。