Science Daily

Scientists have reconstructed the ancient atmospheric carbon dioxide (CO2) record from about 300 million years ago. Their study reveals previously unknown fluctuations of atmospheric CO2 at levels projected for current century, they say. It also highlights the potential impact the loss of tropical forests can have on climate.

Low-frequency vibrations of the Ross Ice Shelf are likely causing ripples and undulations in the air above Antarctica, a new study finds. Using mathematical models of the ice shelf, the study's authors show how vibrations in the ice match those seen in the atmosphere, and are likely causing these mysterious atmospheric waves.

Environmental contaminants such as PFASs can be transferred from mother to offspring through the placenta and mother's milk, exposing the young mammal before and after birth. PFASs are a family of human-made chemicals, which have been used in a number of consumer products such as textiles, carpets, paper plates and food packaging because they repel grease, water and stains and are heat resistant. Since it was discovered that they pose a risk to wildlife and human health, some PFASs have been phased out of use, but they have not been universally banned.

Bolivian glaciers shrunk by 43% between 1986 and 2014, and will continue to diminish if temperatures in the region continue to increase. Glacier recession is leaving lakes that could burst and wash away villages or infrastructure downstream, warns one expert.

August's warmth spread into September, contributing to the warmest year to date for the globe, but not enough to continue the recent 16-month streak of record warmth, according to the U.S. National Oceanic and Atmospheric Administration. Even so, September 2016 ranked as the second warmest September on record.

The first large-scale map of rainfall declines revealed by signatures in ancient soil could help researchers better understand profound regional and global climate transformation.

The same hotspot in Earth's mantle that feeds Iceland's active volcanoes has been playing a trick on the scientists who are trying to measure how much ice is melting on nearby Greenland. According to a new study, the hotspot softened the mantle rock beneath Greenland in a way that ultimately distorted their calculations for ice loss in the Greenland ice sheet. This caused them to underestimate the melting by about 20 gigatons (20 billion metric tons) per year.

New research reveals how a single warming event in Antarctica may be an indication of future ecosystem changes. Stationed in East Antarctica's McMurdo Dry Valleys -- a polar desert that's among the driest places on Earth -- the research team studied the effects of massive flooding caused by the glaciers that melted when air temperatures suddenly warmed to 39 degrees Fahrenheit. Flooding streams eroded, lake ice thinned, lake levels rose, and water reached new places across the barren landscape.

Geomorphologists who study Earth’s surface features and the processes that formed them have long been interested in how floods, in particular catastrophic outbursts that occur when a glacial lake ice dam bursts, for example, can change a planet’s surface, not only on Earth but on Mars. Now geoscience researchers have proposed and tested a new model of canyon-forming floods that suggests that deep canyons can be formed in bedrock by significantly less water than previously thought.

In pictures, the Arctic appears pristine and timeless with its barren lands and icy landscape. In reality, the area is rapidly changing. Scientists are working to understand the chemistry behind these changes to better predict what could happen to the region in the future. One team reports that sea salt could play a larger role in the formation of local atmospheric pollutants than previously thought.

Every school child knows that ice melts in the summer and freezes in the winter. But it turns out that the process isn’t that simple in the Arctic, where one type of sea ice structure, called an ice ridge, can actually get stronger in the summer due to melting.

Scientists examining naturally occurring uranium levels in ancient deep sea corals have discovered new insights into how the major northern ice sheets retreated during the last major deglaciation on Earth.

Carbon dioxide levels in Earth's atmosphere passed a troubling milestone for good this summer and locked in levels of the heat-trapping gas not seen for millions of years.

The ocean circulation that is responsible for England's mild climate appears to be slowing down. The shift is not sudden or dramatic, as in the 2004 sci-fi movie "The Day After Tomorrow," but it is a real effect that has consequences for the climates of eastern North America and Western Europe.

New research shows that the longest and highest-quality records of historical ocean water levels may underestimate the amount of global average sea level rise that occurred during the 20th century.

Researchers have compiled 30 years of data to construct the first ice core-based record of atmospheric oxygen concentrations spanning the past 800,000 years. The record shows that atmospheric oxygen has declined 0.7 percent relative to current atmospheric-oxygen concentrations, a reasonable pace by geological standards, the researchers said. During the past 100 years, however, atmospheric oxygen has declined by a comparatively speedy 0.1 percent because of the burning of fossil fuels, which consumes oxygen and produces carbon dioxide.

Earlier recent work has shown that the east, southeast and northwest regions of the Greenland ice sheet have contributed to 77% of the total mass loss over the last century. Now, researchers have used GPS data to show that the east, southeast and northwest also contributed significantly to ice mass loss in the past, over thousands of years: about 40% of the total loss of ice mass.

By analyzing ice cores drilled from deep inside the Greenland ice sheet, researchers have started to calculate how much Arctic sea ice there was in the past.

A shift in westerly winds, which has led to climate impacts in Australia and the Southern Ocean, is human-induced, new research suggests. To date, limited data on Antarctic climate has meant that it’s been difficult to disentangle changes caused by human activity from natural fluctuations.

New research shows that human pollution of the atmosphere with acid is now almost back to the level that it was before the pollution started with industrialization in the 1930s. The results come from studies of the Greenland ice sheet.