A look at the past suggests atmospheric rivers inundating California could get worse
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Over the past two winters, parts of California have seen much more rain than is normal for the region. The reason for it has been the creation of what have come to be called atmospheric rivers over parts of the Pacific Ocean, which dump wave after wave of rain as they move over land.
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For this new study, the researchers focused on the history of atmospheric rivers dumping rain on California. They traveled to Leonard Lake in northern California to collect core sediment samples. The lake was chosen due to its relatively stable history going back thousands of years and its geographical features.
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In studying the core samples, the research team found evidence of the largest atmospheric river events, which both exceeded those from recent years, occurring two and three millennia ago and dumping massive amounts of rainfall in the region.
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