Evaluation of reconstructed multi-decadal lake levels using ICESat, ICESat-2, and Landsat satellites

Overview: This dataset contains lake hypsometry and time-varying lake levels (1992-2018) for 342 lakes worldwide with sizes ranging from 1 to 81,844 km2. The method is described in detail in Yao et al., Water Resources Research (in review), but a quick overview is provided here.

1. We developed a proxy-based approach to reconstruct global-scale, multi-decadal lake levels using water areas and hypsometric curves.

2. We depended on elevation measurements from laser altimeters ICESat and ICESat-2 and water areas from Landsat imagery to construct lake hypsometry.

3. We used dynamic water masks to reduce the uncertainties in water levels derived from ICESat and ICESat-2.

4. We refined water areas mapped from Landsat based on topographic constraints on lake growth and shrinkage and levels from ICESat and ICESat-2.

5. We validated the method on 342 lakes against observed long-term water levels from in-situ gauges or satellite radar altimeters.

This dataset includes:

1. Lake hypsometry from Landsat, ICESat, and ICESat-2 satellites

2. Reconstructed water levels using Landsat-derived water areas and hypsometric curves

3. Reference level data

概述：本数据集收录了全球342个面积介于1至81844平方千米的湖泊的湖泊高程-面积分布（lake hypsometry）与1992-2018年的时序湖泊水位数据。相关研究方法详见Yao等人发表于《Water Resources Research》（审稿中）的学术论文，此处仅作简要概述。

1. 我们采用替代指标法，基于水域面积与高程-面积分布曲线重建了全球尺度的多年代际湖泊水位序列。
2. 我们依托激光高度计ICESat与ICESat-2的高程测量数据，以及Landsat遥感影像提取的水域面积，构建了湖泊高程-面积分布数据集。
3. 我们采用动态水域掩码（dynamic water masks），降低了由ICESat及ICESat-2反演水位所引入的不确定性。
4. 我们基于湖泊扩张与收缩的地形约束条件，结合ICESat与ICESat-2获取的水位数据，对Landsat影像解译得到的水域面积进行了精细化修正。
5. 我们选取342个湖泊，利用原位水位监测站或卫星雷达高度计获取的长期实测水位数据，对本方法进行了验证。

本数据集包含以下内容：
1. 基于Landsat、ICESat及ICESat-2卫星获取的湖泊高程-面积分布
2. 利用Landsat反演水域面积结合高程-面积分布曲线重建得到的湖泊水位序列
3. 参考水位数据集