Monitoring of seasonal glacier mass balance over the European Alps using low-resolution optical satellite images
Monitoring of seasonal glacier mass balance over the European Alps using low-resolution optical satellite images
复制标题
使用低分辨率光学卫星图像监测欧洲阿尔卑斯山的季节性冰川质量平衡
作者：
V. Drolon;P. Maisongrande;E. Berthier;E. Swinnen;M. Huss
摘要探索一种利用低分辨率光学遥感反演季节性冰川物质平衡的新方法。我们推导出1998-2014年期间使用SPOT/VEGETATION 1 km分辨率图像的阿尔卑斯山冬季和夏季年度雪图。我们将联合收割机这些季节性雪图与DEM相结合，以计算冰川周围区域的“平均区域”积雪高度（Z）。然后，我们比较了年际变化的Z与观测到的冬/夏冰川MB 55阿尔卑斯山冰川在1998-2008年，我们的校准期。我们发现在冬季（平均R2 = 0.84）和重建的冬季MB（平均RMSE = 158 mm（w.e.）a−1）。这低于冰川学MB测量（200-400 mm w.e.）通常假设的误差。a−1）。夏季MB的结果也令人满意（平均R2和RMSE分别为0.74和314 mm w.e.）。a−1）。与2009-2014年（我们的评估期）观测到的冬季19个冰川和夏季13个冰川的季节性甲基溴数据相比，冬季的一致性很好（RMSE = 405毫米湿当量）。a−1）和夏季稍大的误差（RMSE = 561 mm w.e. a−1）。这些结果表明，我们的方法可能是有价值的远程确定大区域的冰川的季节性MB。
ABSTRACT We explore a new method to retrieve seasonal glacier mass balances (MBs) from low-resolution optical remote sensing. We derive annual winter and summer snow maps of the Alps during 1998–2014 using SPOT/VEGETATION 1 km resolution imagery. We combine these seasonal snow maps with a DEM to calculate a ‘mean regional’ altitude of snow (Z) in a region surrounding a glacier. Then, we compare the interannual variation of Z with the observed winter/summer glacier MB for 55 Alpine glaciers over 1998–2008, our calibration period. We find strong linear relationships in winter (mean R 2 = 0.84) and small errors for the reconstructed winter MB (mean RMSE = 158 mm (w.e.) a−1). This is lower than errors generally assumed for the glaciological MB measurements (200–400 mm w.e. a−1). Results for summer MB are also satisfying (mean R 2 and RMSE, respectively, 0.74 and 314 mm w.e. a−1). Comparison with observed seasonal MB available over 2009–2014 (our evaluation period) for 19 glaciers in winter and 13 in summer shows good agreement in winter (RMSE = 405 mm w.e. a−1) and slightly larger errors in summer (RMSE = 561 mm w.e. a−1). These results indicate that our approach might be valuable for remotely determining the seasonal MB of glaciers over large regions.