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Today's ice sheets may be more resilient to increased carbon dioxide levels than previously thought, a new study suggests. This work explored these very old conditions and found that sea level might not have risen as much as previously thought -- and thus may not rise as fast as predicted now.

The mass balance of glaciers is mainly influenced by winter precipitation and summer temperature. In a recent study, researchers used simple statistical models to assess and quantify the relative importance of summer temperature and winter precipitation for annual mass balances of eight Scandinavian glaciers.

Fifty million years ago, the Cowboy State was crawling with crocodiles. Fossil records show that crocs lounged in the shade of palm trees from southwestern Wyoming to southern Canada during the Cretaceous and Eocene.  Exactly how the middle of the North American continent -- far from the warming effects of the ocean -- stayed so temperate even in winter months has long eluded scientists.

A well-known period of abrupt climate change 12,000 years ago occurred rapidly in northern latitudes but much more gradually in equatorial regions, a discovery that could prove important for understanding and responding to future climate change, scientists say.

At the bottom of a frigid Antarctic lake, a thin layer of green slime is generating a little oasis of oxygen, a team of researchers has found. It's the first modern replica discovered of conditions on Earth two and a half billion years ago, before oxygen became common in the atmosphere.

Ice experts have developed a straightforward new technique for estimating sea ice concentration in the Arctic Ocean, and the new method improves the US Navy's short-term sea ice forecast of ice edge location by almost 40 percent. With shipping on the rise in the Arctic Ocean, improving these short-term forecasts makes navigating in Arctic waters safer.

On Greenland's ice sheet, a vast icy landscape crisscrossed by turquoise rivers and dotted with meltwater lakes, a small cluster of orange camping tents popped up in late July. The camp, home for a week to a team of researchers, sat by a large, fast-flowing river. Just half a mile (a kilometer) downstream, the river dropped into a seemingly bottomless moulin, or sinkhole in the ice. The low rumble of the waters, the shouted instructions from scientists taking measurements, and the chop of the blades of a helicopter delivering personnel and gear were all that was heard in the frozen landscape.

Earlier this month, a NASA instrument nestled in the belly of a small plane flew over Greenland's ice sheet and the Arctic Ocean's icy waters. Flying above creviced glaciers, chunks of ice floating in melt ponds, and the slushy edges of the ice sheets, the instrument used a rapidly firing laser to measure the elevation of the surface below.

WHRC scientists have counseled the State Department on policies that could control permafrost thaw, including reducing global carbon emissions from fossil fuel use and deforestation, and limiting emissions of 'black carbon,' sooty particles that darken snow and ice and hasten Arctic warming.

The membranes of sediment-entombed archaea are an increasingly popular way to determine ocean surface temperatures back to the age of the dinosaurs. But new results show that changing oxygen can affect the reading by as much as 21 degrees C.

According to the 23-year record of satellite data from NASA and its partners, the sea level is rising a few millimeters a year -- a fraction of an inch. If you live on the U.S. East Coast, though, your sea level is rising two or three times faster than average. If you live in Scandinavia, it's falling. Residents of China's Yellow River delta are swamped by sea level rise of more than nine inches (25 centimeters) a year. These regional differences in sea level change will become even more apparent in the future, as ice sheets melt.

For thousands of years, sea level has remained relatively stable and human communities have settled along the planet's coastlines. But now Earth's seas are rising. Globally, sea level has risen about eight inches (20 centimeters) since the beginning of the 20th century and more than two inches (5 centimeters) in the last 20 years alone. All signs suggest that this rise is accelerating.

Seas around the world have risen an average of nearly 3 inches (8 centimeters) since 1992, with some locations rising more than 9 inches (25 centimeters) due to natural variation, according to the latest satellite measurements from NASA and its partners. An intensive research effort now underway, aided by NASA observations and analysis, points to an unavoidable rise of several feet in the future.

The second ice age during the Cryogenian period was not followed by the sudden and chaotic melting-back of the ice as previously thought, but ended with regular advances and retreats of the ice, according to new research.

A recalculation of the dates at which boulders were uncovered by melting glaciers at the end of the last Ice Age has conclusively shown that the glacial retreat was due to rising levels of carbon dioxide and other greenhouse gases, as opposed to other types of forces. The data helps to confirm predictions of future glacial retreat, and that most of the world's glaciers may disappear in the next few centuries.

The July average temperature across global land and ocean surfaces was 1.46°F (0.81°C) above the 20th century average. As July is climatologically the warmest month for the year, this was also the all-time highest monthly temperature in the 1880-2015 record, at 61.86°F (16.61°C), surpassing the previous record set in 1998 by 0.14°F (0.08°C).

In the Arctic, enhanced vegetation growth amplifies global warming. On the Tibetan Plateau, however, the situation is the reverse. “The trend in Tibet is the opposite of what we are seeing in the Arctic,” says an expert. “By restoring grasslands there, the climate can be improved – both locally and globally.”

A new international study is the first to use a high-resolution, large-scale computer model to estimate how much ice the West Antarctic Ice Sheet could lose over the next couple of centuries, and how much that could add to sea-level rise. The results paint a clearer picture of West Antarctica's future than was previously possible.

Along the Tien Shan, Central Asia's largest mountain range, glaciers have lost 27 percent of their mass and 18 percent of their area during the last 50 years. Glaciers play an important role in the water cycle of Central Asia. Snow and glacier melt from the Tien Shan is essential for the water supply of Kazakhstan, Kyrgyzstan, Uzbekistan, and parts of China.

Prior to the advent of human-caused global warming in the 19th century, the surface layer of Earth's oceans had undergone 1,800 years of a steady cooling trend, according to a new study. The results also indicate that the coolest temperatures occurred during the Little Ice Age -- a period that spanned the 16th through 18th centuries and was known for cooler average temperatures over land.