Increased Amazon Basin wet-season precipitation and river discharge since the early 1990s driven by tropical Pacific variability
نویسندگان
چکیده
Abstract The Amazon Basin, the largest watershed on Earth, experienced a significant increase in wet-season precipitation and high-season river discharge from early 1990s to 2010s. Some studies have linked increased Basin hydrologic cycle decadal trends of Pacific trade winds, eastern sea surface temperature (SST) cooling, associated strengthening Walker circulation. However, it has been difficult disentangle role variability impacts greenhouse gases other external climate drivers over same period. Here, we separate contributions forcings those by comparing two large ensembles model experiments with identical radiative forcing agents but imposing different tropical wind stress. One ensemble constrains stress its long-term climatology, suppressing variability; imposes observed anomalies, simulating realistic variability. Comparing hydroclimate response allows us distinguish common both simulations related For 1992–2012 trend, anomalies simulate circulation between South America sharpening Pacific–Atlantic interbasin SST contrast, driving discharge. In these intensification are absent climatological This work underscores importance hydrological changes modulating global warming Basin.
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ژورنال
عنوان ژورنال: Environmental Research Letters
سال: 2021
ISSN: ['1748-9326']
DOI: https://doi.org/10.1088/1748-9326/abd587