Large-scale changes in Earth’s climate may originate in the Pacific

The retreat of North America’s ice sheets in the latter years of the last ice age may have begun with “catastrophic” losses of ice into the North Pacific Ocean along the coast of modern-day British Columbia and Alaska, scientists say. 

In a new study published October 1 in Science, researchers find that these pulses of rapid ice loss from what’s known as the western Cordilleran ice sheet contributed to, and perhaps triggered, the massive calving of the Laurentide ice sheet into the North Atlantic Ocean thousands of years ago. That collapse of the Laurentide ice sheet, which at one point covered large swaths of Canada and parts of the United States, ultimately led to major disturbances in the global climate (SN: 11/5/12).

The new findings cast doubt on the long-held assumption that hemispheric-scale changes in Earth’s climate originate in the North Atlantic (SN: 1/31/19). The study

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Newly identified ‘landfalling droughts’ originate over ocean — ScienceDaily

Meteorologists track hurricanes over the oceans, forecasting where and when landfall might occur so residents can prepare for disaster before it strikes. What if they could do the same thing for droughts?

Stanford scientists have now shown that may be possible in some instances — the researchers have identified a new kind of “landfalling drought” that can potentially be predicted before it impacts people and ecosystems on land. They found that these droughts, which form over the ocean and then migrate landward, can cause larger and drier conditions than droughts that occur solely over the land. Of all the droughts affecting land areas worldwide from 1981 to 2018, roughly one in six were landfalling droughts, according to the study published Sept. 21 in Water Resources Research.

“We normally don’t think about droughts over the ocean — it may even sound counterintuitive. But just as over land, there can be times

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