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Climate Change Drove Neanderthals to Cannibalism, New Research Suggests

Neanderthals are famous for having lived through the last major ice age, yet for a period of around 14,000 years they had to endure the effects of a naturally occurring global warming cycle. Struggling to adapt to the changing conditions, the Neanderthals turned to cannibalism in desperation, according to a provocative and timely new study.

gizmodo.com|George Dvorsky

New research published this week in the Journal of Archaeological Science suggests the crushing impact of the Last Interglacial Period, also known as the Eemian period, forced Neanderthals into cannibalism. This era of prehistory, between 128,000 to 114,000 years ago, saw global temperatures rise to about 2 degrees Celsius higher that the average global temperature in the 20th century. 

The archaeologists who authored the new study, Alban Defleur and Emmanuel Desclaux from French National Center for Scientific Research, presented new evidence showing how the sharp spike in temperature reshaped the Eurasian environment, and by consequence, the animals upon which the Neanderthals depended.

Scientists already knew that the Neanderthals of the Baume Moula-Guercy practiced cannibalism, but the link to climate change is new. On that note, the authors provided an ecological snapshot of Eemian Europe, highlighting the changing environmental conditions and the types of food available to the Neanderthals. Where grasslands once dominated the landscape, temperate forests crept in. Large prey animals such as mammoths, giant deer, straight-tusked elephants, and narrow-nosed rhinos were replaced by rodents, porcupines, snakes, and reptiles (including tortoises), many of which migrated north up from the Mediterranean region.

Neanderthals, she speculated, could have practiced cannibalism as a way to survive prolonged periods of food insecurity or desperation.

There's a Huge Cavity Under Antarctica's Most Endangered Glacier

Antarctica is the font of bad news that just keeps on giving. Thwaites Glacier, among the most threatened hunks of ice on the continent, is in even more dire straits than previously reported. Its melt from above and below is being aided by newly discovered cavities below the ice, as chronicled in Science Advances on Wednesday.

earther.gizmodo.com|Brian Kahn

Thwaites Glacier is located in West Antarctica, an area that is facing what could be runaway melt owing to geography and inescapable heat. The bedrock under Thwaites and other glaciers in the region slopes downward further inland, allowing that warm water to rot out the glaciers from underneath. The region is the fastest melting part of Antarctica, and losing the land ice could lead to more than 10 feet of sea level rise.

The gaping hole in the ice has a footprint two-thirds the size of Manhattan and is tall enough to fit the Statue of Liberty three times over.

“[The size of] a cavity under a glacier plays an important role in melting,” said the study’s lead author, Pietro Milillo, a scientist at NASA Jet Propulsion Laboratory who led the study, said in a press release. “As more heat and water get under the glacier, it melts faster.”

The glacier isn’t retreating uniformly. The fastest retreat of floating ice is about a half mile a year with various areas thinning at up to 650 feet per year.

U.S. Climate Report Warns of Damaged Environment and Shrinking Economy

Without major action to rein in global warming, the American economy could lose 10 percent of G.D.P. by 2100, according to a report from 13 federal agencies.

www.nytimes.com

A major scientific report issued by 13 federal agencies on Friday presents the starkest warnings to date of the consequences of climate change for the United States, predicting that if significant steps are not taken to rein in global warming, the damage will knock as much as 10 percent off the size of the American economy by century’s end.

The report, which was mandated by Congress and made public by the White House, is notable not only for the precision of its calculations and bluntness of its conclusions, but also because its findings are directly at odds with President Trump’s agenda of environmental deregulation, which he asserts will spur economic growth.

But in direct language, the 1,656-page assessment lays out the devastating effects of a changing climate on the economy, health and environment, including record wildfires in California, crop failures in the Midwest and crumbling infrastructure in the South. Going forward, American exports and supply chains could be disrupted, agricultural yields could fall to 1980s levels by midcentury and fire season could spread to the Southeast, the report finds.

The findings come a month after the Intergovernmental Panel on Climate Change, a group of scientists convened by the United Nations, issued its most alarming and specific report to date about the severe economic and humanitarian crises expected to hit the world by 2040. 

The nation’s farm belt is likely to be among the hardest-hit regions, and farmers in particular will see their bottom lines threatened.

“Rising temperatures, extreme heat, drought, wildfire on rangelands and heavy downpours are expected to increasingly disrupt agricultural productivity in the U.S.,” the report says. “Expect increases in challenges to livestock health, declines in crop yields and quality and changes in extreme events in the United States and abroad.”

By 2050, the scientists forecast, changes in rainfall and hotter temperatures will reduce the agricultural productivity of the Midwest to levels last seen in the 1980s.

Climate change: The Arctic as it is known today is almost certainly gone | The Economist

On current trends, the Arctic will be ice-free in summer by 2040

www.economist.com

THOSE who doubt the power of human beings to change Earth’s climate should look to the Arctic, and shiver. There is no need to pore over records of temperatures and atmospheric carbon-dioxide concentrations. The process is starkly visible in the shrinkage of the ice that covers the Arctic ocean. In the past 30 years, the minimum coverage of summer ice has fallen by half; its volume has fallen by three-quarters.

The Arctic is not merely a bellwether of matters climatic, but an actor in them (see pages Briefing).

If the Arctic heats faster than the tropics, this difference will decrease and wind speeds will slow—as they have done, in the northern hemisphere, by between 5 and 15% in the past 30 years. Less wind might sound desirable. It is not. One consequence is erratic behaviour of the northern jet stream, a circumpolar current, the oscillations of which sometimes bring cold air south and warm air north. More exaggerated oscillations would spell blizzards and heatwaves in unexpected places at unexpected times.

NASA Scientists Suggest We’ve Been Underestimating Sea Level Rise

Sea level rise has been underestimated by up to 28 percent in some areas.

motherboard.vice.com

But a new study, published this month to Geophysical Research Letters, found evidence to suggest that historical sea level records have been off—way off in some areas—by an underestimation of 5 to 28 percent. Global sea level, the paper concluded, rose no less than 5.5 inches over the last century, and likely saw an increase of 6.7 inches.

In terms of sea level changes, however, the study found the effects of melting are more drastically felt in regions farther from its source. According to InsideClimate News, melting sea ice in the Northern Hemisphere might raise water levels more in “the southern Pacific Ocean and equatorial regions.” 

Total global ice melt since 1900 is about equal to the amount of water in Lake Superior, about 2 quadrillion gallons, which is enough to cover North and South America in a foot of water. It's pouring into the oceans at a steady, gradually increasing rate, but it's not as simple as filling a bathtub. Propelled by the spin of the Earth, shifting gravitational fields, seasonal changes and wind, all that water sloshes around in a pattern that satellites can see.

This color-coded map in Robinson projection displays a progression of changing global surface temperature anomalies from 1880 through 2015. Higher than normal temperatures are shown in red and lower then normal termperatures are shown in blue. The final frame represents the global temperatures 5-year averaged from 2010 through 2015. Scale in degree Celsius. Download the visualization: http://svs.gsfc.nasa.gov/cgi-bin/deta....

How Earth's coastlines would look if all ice melted (bye Florida!)

sploid.gizmodo.com

National Geographic made precise maps on how Earth would look in the case all the planet's ice melted. The bad news: New York, San Francisco, New Orleans, London and other cool cities would be completely gone. The good news: the entire state of Florida would disappear.

Unprecedented Arctic warming: Average summer temperatures in last 100 years may be warmest in 120,000 years

www.sciencedaily.com

Average summer temperatures in the Eastern Canadian Arctic during the last 100 years are higher now than during any century in the past 44,000 years and perhaps as long ago as 120,000 years, says a new study.

NASA has just put out a time-lapse video showing how the changing climate is expected to impact our world between now and 2099.

Based on the agency’s models for climate and weather trends, NASA predicts that temperatures and rainfall will change drastically during the century to come. Globally, temperatures are expected to rise significantly. Precipitation will increase and decrease differently for various locations around the globe.