Arctic sea ice, the vast sheath of frozen seawater floating on the Arctic Ocean and its neighboring seas, has been hit with a double whammy over the past decades: as its extent shrunk, the oldest and thickest ice has either thinned or melted away, leaving the sea ice cap more vulnerable to the warming ocean and atmosphere.

“What we’ve seen over the years is that the older ice is disappearing,” said Walt Meier, a sea ice researcher at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “This older, thicker ice is like the bulwark of sea ice: a warm summer will melt all the young, thin ice away but it can’t completely get rid of the older ice. But this older ice is becoming weaker because there’s less of it and the remaining old ice is more broken up and thinner, so that bulwark is not as good as it used to be.”

The bulk of methane emissions in the United States can be traced to a small number of “super emitting” natural gas wells, according to a new study.

“We’re finding that when it comes to natural gas leaks, a 50/5 rule applies: That is, the largest 5 percent of leaks are typically responsible for more than 50 percent of the total volume of leakage,” said study co-author Adam Brandt, an assistant professor of energy resources engineering at Stanford’s School of Earth, Energy & Environmental Sciences.

The findings, published online in the journal Environmental Science & Technology, could lead to more efficient strategies for sampling emissions and fixing the most significant leaks, said Brandt, who is also a senior fellow at Stanford’s Precourt Institute for Energy. By focusing on finding and fixing the biggest emitters, companies can significantly reduce the amount of methane leaking into the atmosphere.

Plants are adapting to increasing atmospheric carbon dioxide according to a new study from the University of Southampton

The research, published in the journal Global Change Biology, provides insight into the long-term impacts of rising CO2 and the implications for global food security and nature conservation.

Lead author Professor Gail Taylor, from Biological Sciences at the University of Southampton, said: “Atmospheric CO2 is rising – emissions grew faster in the 2000s than the 1990s and the concentration of CO2 reached 400 ppm for the first time in recorded history in 2013.

Two new studies by researchers at the University of California, Irvine and NASA have found the fastest ongoing rates of glacier retreat ever observed in West Antarctica and offer an unprecedented look at ice melting on the floating undersides of glaciers. The results highlight how the interaction between ocean conditions and the bedrock beneath a glacier can influence the frozen mass, helping scientists better predict future Antarctica ice loss and global sea level rise.

The studies examined three neighboring glaciers that are melting and retreating at different rates. The Smith, Pope and Kohler glaciers flow into the Dotson and Crosson ice shelves in the Amundsen Sea embayment in West Antarctica, the part of the continent with the largest decline in ice.

The stomachs of cattle, fermentation in rice fields, fracking for natural gas, coal mines, festering bogs, burning forests — they all produce methane, the second most important greenhouse gas, after carbon dioxide. But how much? And how can we best cut these emissions? And is fracking frying the planet, or are bovine emissions more to blame? 

Globally averaged concentration of carbon dioxide in the atmosphere reached the symbolic and significant milestone of 400 parts per million for the first time in 2015 and surged again to new records in 2016 on the back of the very powerful El Niño event, according to the World Meteorological Organization's annual Greenhouse Gas Bulletin.

Understanding how tiny particles emitted by cars and factories affect Earth's climate requires accurate climate modeling and the ability to quantify the effects of these pollutant particles vs. particles naturally present in the atmosphere. One large uncertainty is what Earth was like before these industrial-era emissions began. In a paper just published in Nature, scientists collaborating on the GoAmazon study describe how they tracked particles in the largely pristine atmosphere over the Amazon rainforest, which has given them a way to effectively turn back the clock a few hundred years.  

Climate change is disrupting the sensory systems of fish and can even make them swim towards predators, instead of away from them, a paper by marine biologists at the University of Exeter says.

Research into the impact of rising CO2 has shown it can disrupt the senses of fish including their smell, hearing and vision.

Research by the University of Southampton shows that a change in the patterns of tropical storms is threatening the future of the Mekong River delta in Vietnam, indicating a similar risk to other deltas around the world.

The study, funded by the UK Natural Environment Research Council (NERC) and undertaken in collaboration with the universities of Exeter (UK), Hull (UK), Illinois (USA) and Aalto University (Finland), found that changes in the behaviour of cyclones mean less sediment is running into rivers upstream of the Mekong delta, starving it of material vital for guarding against flooding. The findings are published in the journal Nature.

A new multiyear study from scientists at the Woods Hole Oceanographic Institution (WHOI) has shown for the first time how changes in ocean temperature affect a key species of phytoplankton. The study, published in the October 21 issue of the journal Science, tracked levels of Synechococcus—a tiny bacterium common in marine ecosystems—near the coast of Massachusetts over a 13-year period. As ocean temperatures increased during that time, annual blooms of Synechococcus occurred up to four weeks earlier than usual because cells divided faster in warmer conditions, the study found.