Complex influences of meteorological drought time-scales on hydrological droughts in natural basins of the contiguous Unites States
Complex influences of meteorological drought time-scales on hydrological droughts in natural basins of the contiguous Unites States
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DOI：
10.1016/j.jhydrol.2018.11.026
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发表时间：
2019
影响因子：
6.4
通讯作者：
M. Peña‐Gallardo;S. Vicente‐Serrano;J. Hannaford;J. Lorenzo-Lacruz;M. Svoboda;F. Domínguez‐Castro
中科院分区：
文献类型：
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作者：
M. Peña‐Gallardo;S. Vicente‐Serrano;J. Hannaford;J. Lorenzo-Lacruz;M. Svoboda;F. Domínguez‐Castro
我们使用美国境内非常密集和多样化的测量自然流域网络来分析气象干旱和水文干旱之间的关系。具体来说，这项工作使用了涵盖 1940 年至 2013 年期间 289 个测量站的数据集。使用数字地形模型获得每个测量站的排水盆地。除了气象数据（例如降水、气温和大气蒸发需求）外，我们还获得了每个定义的流域的许多地形、土壤和遥感变量。计算每个流域的水文干旱指数（标准化径流量指数；SSI），并将其与标准化降水蒸散指数（SPEI）联系起来，后者用作气候干旱严重程度的指标。通过皮尔逊相关系数评估不同 SPEI 时间尺度与其相应 SSI 之间的关系。此外，还利用主成分分析确定了水文干旱对气候干旱响应的一般模式。总体而言，结果表明 SSI 在较短的时间尺度上对 SPEI 做出了积极的响应，具有很强的季节性和明显的空间差异。我们还使用预测判别分析评估了一些气候和环境因素在解释这些不同反应中的作用。结果表明，海拔和植被覆盖度是 SSI 对 SPEI 时间尺度不同响应的主要驱动因素。对三个子时期（1940-1964年、1965-1989年和1989-2013年）进行了类似的分析，其结果证实了过去八十年来SSI对SPEI的反应存在显着差异。
We analyzed the relationships between meteorological drought and hydrological drought using very dense and diverse network of gauged natural drainage basins across the conterminous U.S. Specifically, this work utilized a dataset of 289 gauging stations, covering the period 1940–2013. Drainage basins were obtained for each gauging station using a digital terrain model. In addition to meteorological data (e.g., precipitation, air temperature and the atmospheric evaporative demand), we obtained a number of topographic, soil and remote sensing variables for each defined drainage basin. A hydrological drought index (the Standardized Streamflow Index; SSI) was computed for each basin and linked to the Standardized Precipitation Evapotranspiration Index (SPEI), which was used as a metric of climatic drought severity. The relationships between different SPEI time-scales and their corresponding SSI were assessed by means of a Pearson correlation coefficient. Also, the general patterns of response of hydrological droughts to climatic droughts were identified using a principal component analysis. Overall, results demonstrate a positive response of SSI to SPEI at shorter time-scales, with strong seasonality and clear spatial differences. We also assessed the role of some climatic and environmental factors in explaining these different responses using a predictive discriminant analysis. Results indicate that elevation and vegetation coverage are the main drivers of the diverse response of SSI to SPEI time-scales. Similar analyses were made for three sub-periods (1940–1964, 1965–1989 and 1989–2013), whose results confirm considerable differences in the response of SSI to SPEI over the past eighty years.