美国加州理工学院Elyssa L. Collins团队在研究中取得进展。他们发现了河流储水量随停留时间变化的全球格局。2024年4月22日出版的《自然—地球科学》杂志发表了这项成果。
研究人员利用全球河流流量观测和陆地表面模型的集合，来生成一个全球测量校正的月度河流流量和存储数据集。研究小组估计全球河流储水量平均值(±月变化)为2,246±505 km3，全球大陆流量为37,411±7,816 km3 /年。他们的全球河流储水时间序列表明，流波停留时间是一个基本的驱动因素，可以使河流储水量及其变异性增加一倍或减半。
课题组还调和了以前对全球河流流量月度变化估计的大范围。研究人员确定了以前未被重视的从海洋大陆(印度尼西亚、马来西亚和巴布亚新几内亚)流入海洋的淡水资源，其总量是刚果河的1.6倍，并阐明了它们检测严重人为取水的能力。
据悉，对全球河流流量和储存量的准确评估对于水管理实践至关重要，但目前对全球河流流量的估计显示出很大的差异，而对河流储存量的估计仍然很少。由于土地径流的不确定性，对河流流量和储水量的估计受到阻碍，而土地径流是向河流提供水的一种未观察到的量。
附：英文原文
Title: Global patterns in river water storage dependent on residence time
Author: Collins, Elyssa L., David, Cdric H., Riggs, Ryan, Allen, George H., Pavelsky, Tamlin M., Lin, Peirong, Pan, Ming, Yamazaki, Dai, Meentemeyer, Ross K., Sanchez, Georgina M.
Issue&Volume: 2024-04-22
Abstract: Accurate assessment of global river flows and stores is critical for informing water management practices, but current estimates of global river flows exhibit substantial spread and estimates of river stores remain sparse. Estimates of river flows and stores are hampered by uncertainties in land runoff, an unobserved quantity that provides water input to rivers. Here we leverage global river flow observations and an ensemble of land surface models to generate a globally gauge-corrected monthly river flow and storage dataset. We estimate a global river storage mean (± monthly variability) of 2,246±505 km3 and a global continental flow of 37,411±7,816km3yr1. Our global river water storage time series demonstrates that flow wave residence time is a fundamental driver that can double or halve river water stores and their variability. We also reconcile the wide range in previous estimates of monthly variability in global river flows. We identify previously underappreciated freshwater sources to the ocean from the Maritime Continent (Indonesia, Malaysia and Papua New Guinea) amounting to 1.6 times the Congo River and illustrate our capability of detecting severe anthropogenic water withdrawals.
DOI: 10.1038/s41561-024-01421-5
Source: https://www.nature.com/articles/s41561-024-01421-5