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Massive freshwater river flows stemming from glacier-fed flooding at the end of the last ice age surged across eastern Washington to the Columbia River and out to the North Pacific Ocean, where they triggered climate changes throughout the northern hemisphere.

Anthropologists have found out that prehistoric migration from Africa, Asia and Europe to the Mediterranean islands took place long before the era of the Mediterranean seafaring civilizations. For their analysis they used the DNA of prehistoric individuals from Sicily, Sardinia and the Balearic Islands.

The decision of each individual bear to stay on the ice or to move to land appears to be linked to the energetic cost or benefit of either option, and the potential of having to swim to reach land.

New research has revealed new insights into how the microscopic algae that thrives along the edge of the Greenland Ice Sheet causes widespread darkening.

New work shows how using next-generation DNA sequencing on ancient packrat middens -- nests made out of plant material, fragments of insects, bones, fecal matter, and urine -- could provide ecological snapshots of Earth's past. The study may pave the way for scientists to better understand how plant communities -- and possibly animals, bacteria, and fungi as well -- will respond to human-caused climate change.

As global temperatures rise, permafrost and methane hydrates -- large reservoirs of ancient carbon -- have the potential to break down, releasing enormous quantities of the potent greenhouse gas methane. But would this methane actually reach the atmosphere? Researchers found that even if methane is released from these natural stores in response to warming, very little reaches the atmosphere; therefore, anthropogenic emissions should be more concerning than these natural feedbacks.

Climate scientists propose that massive amounts of melting sea ice in the Arctic drained into the North Atlantic and disrupted climate-steering currents, thus playing an important role in causing past abrupt climate change after the last Ice Age, from about 8,000 to 13,000 years ago.

Researchers measured methane levels in ancient air samples and found that scientists have been vastly underestimating the amount of methane humans are emitting into the atmosphere via fossil fuels. The researchers indicate that reducing fossil fuel use is a key target in curbing climate change.

A 784,000 year climate simulation suggests that Southern Ocean sea ice significantly reduces deep ocean ventilation to the atmosphere during glacial periods by reducing both atmospheric exposure of surface waters and vertical mixing of deep ocean waters; in a global carbon cycle model, these effects led to a 40 ppm reduction in atmospheric CO2 during glacial periods relative to pre-industrial level, suggesting how sea ice can drive carbon sequestration early within a glacial cycle.

Mediterranean-type climates face immediate drops in rainfall when greenhouse gases rise, but this could be interrupted quickly if emissions are cut.

Within this century already, due to Antarctica alone global sea level might rise up to three times as much as it did in the last century. This is a finding of an exceptionally comprehensive comparison of state-of-the-art computer models from around the world.

Satellite tracking of adult females and visual monitoring of polar bears in Baffin Bay show changes from the 1990s to the period from 2009 to 2015. Bears in Baffin Bay are getting thinner and adult females are having fewer cubs than when sea ice was more available.

Rising ocean temperatures drove the melting of Antarctic ice sheets and caused extreme sea level rise more than 100,000 years ago, a new international study l shows - and the scientists say we're headed in that direction again.

More frequent and intense rainfall events due to climate change could cause more landslides in the High Mountain Asia region of China, Tibet and Nepal, according to the first quantitative study of the link between precipitation and landslides in the region.

An analysis of the so called climate spectrum shows why the ice ages have not behaved precisely as the models predict. A large element of coincidence is involved when an ice age begins or ends, the analysis shows. The results imply we should maybe use a more conservative risk assessment then the one IPCC recommends.

Human beings altered one of the highest peaks in the Himalayas hundreds of years before a person ever set foot there, new research has found. The study indicates that the byproducts of burning coal in Europe in the late 18th century made their way to the Dasuopu glacier in the central Himalayas, some 6,400 miles as the crow flies from London, the birthplace of the Industrial Revolution.

This new work sheds fresh light on the complicated interplay of factors affecting global climate and the carbon cycle -- and on what transpired millions of years ago to spark two of the most devastating extinction events in Earth's history.

About 55 million years ago, a rapidly warming climate decimated marine communities around the world. But according to new research, it was a different story for snails, clams and other mollusks living in the shallow waters along what is now the Gulf Coast of the United States. They were able to survive.

An emerging scientific consensus is that gases -- in particular carbon gases -- released by volcanic eruptions millions of years ago contributed to some of Earth's greatest mass extinctions. But new research suggests that that's not the entire story.

Using 12 years of satellite data, NASA scientists have measured how the influx of cold, fresh water is affecting the Beaufort Gyre, a major Arctic current.