The report, published in the journal Hydrology and Earth System SciencesExternal link, measured both the melting of glaciers over the course of 40 years and the temperature of rivers they discharge into. They found that rivers had warmed by an average of 0.33°C every decade since 1980, and by 0.37°C per decade over the past 20 years. They also observed a 3% average decrease in meltwater discharge over the past 40 years as glaciers shrink. The trend has accelerated in the past two decades with a 10% decrease in glacial meltwater discharge into rivers.