Seafloor sediment cores reveal abrupt, extensive loss of oxygen in the ocean when ice sheets melted roughly 10,000 to 17,000 years ago, according to a study. The findings provide insight into similar changes observed in the ocean today. In the study, researchers analyzed marine sediment cores from different world regions to document the extent to which low oxygen zones in the ocean have expanded in the past, due to climate change.
Geologists from Brown Univ. have found new evidence that glacier-like ice deposits advanced and retreated multiple times in the mid-latitude regions of Mars in the relatively recent past. For the study, the researchers looked at hundreds of gully-like features found on the walls of impact craters throughout the Martian mid-latitudes.
Scientists have reconstructed the past climate for the region around Cantona, a large fortified city in highland Mexico, and found the population drastically declined in the past, at least in part because of climate change. The research appears in the online edition of the Proceedings of the National Academy of Sciences.
A new study finds that most climate models likely underestimate the degree of decade-to-decade variability occurring in mean surface temperatures as Earth's atmosphere warms. The models also provide inconsistent explanations of why this variability occurs in the first place. These discrepancies may undermine the models' reliability for projecting the short-term pace as well as the extent of future warming, the study's authors warn.
Satellite images have revealed that a remote Arctic ice cap has thinned by more than 50 m since 2012 and that it’s now flowing 25 times faster. A team led by scientists from the Centre for Polar Observation and Modelling (CPOM) at the Univ. of Leeds combined observations from eight satellite missions, including Sentinel-1A and CryoSat, with results from regional climate models, to unravel the story of ice decline.
The Bulletin of the Atomic Scientists says Earth is now closer to human-caused doomsday than it has been in more than 30 years because of global warming and nuclear weaponry. But other experts say that's way too gloomy. The advocacy group founded by the creators of the atomic bomb moved their famed "Doomsday Clock" ahead two minutes on Thursday.
Researchers who are building the highest-resolution map of the Greenland Ice Sheet to date have made a surprising discovery: two lakes of meltwater that pooled beneath the ice and rapidly drained away. One lake once held billions of gallons of water and emptied to form a mile-wide crater in just a few weeks. The other lake has filled and emptied twice in the last two years.
The Republican-controlled Senate acknowledged Wednesday that climate change is real but refused to say humans are to blame. The series of votes publicly tested Republicans' stance on global warming just days after two federal agencies declared 2014 the hottest year on record and hours after President Barack Obama called global warming one of the greatest threats to future generations.
Researchers at Oak Ridge National Laboratory have developed a population distribution model that provides unprecedented county-level predictions of where people will live in the U.S. in the coming decades. Initially developed to assist in the siting of new energy infrastructure, the team’s model has a broad range of implications from urban planning to climate change adaptation.
As the Earth warms and glaciers all over the world begin to melt, researchers and public policy experts have focused largely on how all of that extra water will contribute to sea level rise. But another impact lurking in that inevitable scenario is carbon. More specifically, what happens to all of the organic carbon found in those glaciers when they melt?
For the third time in a decade, the globe sizzled to the hottest year on record, federal scientists announced. Both the National Oceanic and Atmospheric Administration and NASA calculated that in 2014 the world had its hottest year in 135 years of record-keeping. Earlier, the Japanese weather agency and an independent group out of UC Berkeley also measured 2014 as the hottest on record.
An international team of researchers says climate change, the loss of biosphere integrity, land-system change and altered biogeochemical cycles like phosphorus and nitrogen runoff have all passed beyond levels that put humanity in a “safe operating space.” Civilization has crossed four of nine so-called planetary boundaries as the result of human activity, according to a report published in Science by the 18-member research team.
Almost half of the processes that are crucial to maintaining the stability of the planet have become dangerously compromised by human activity. That is the view of an international team of 18 researchers who provide new evidence of significant changes in four of the nine systems which regulate the resilience of the Earth.
Mass die-offs of animals may be increasing in frequency and in severity as well, according to a study of 727 mass mortality events since 1940. Despite the ecological importance of individual mass mortality events, in which a larger than normal number of individuals die within a population, little research has been conducted on patterns across mass mortality events.
The world's oceans are now rising far faster than they did in the past, a new study says. The study found that for much of the 20th century the sea level was about 30% less than earlier research had figured. But that's not good news, scientists say, because about 25 years ago the seas started rising faster and the acceleration in 1990 turns out to be more dramatic than previously calculated.
Penn State Univ. will lead a five-year, $30 million mission to improve quantification of present-day carbon-related greenhouse gas sources and sinks. An improved understanding of these gases will advance our ability to predict and manage future climate change.
The economic damage caused by a ton of carbon dioxide emissions could be six times higher than the value that the U.S. now uses to guide current energy regulations, and possibly future mitigation policies, Stanford Univ. scientists say. A recent U.S. government study concluded, based on the results of three widely used economic impact models, an additional ton of carbon dioxide emitted in 2015 would cause $37 worth of economic damages.
As the largest single chunk of melting snow and ice in the world, the massive ice sheet that covers about 80% of Greenland is recognized as the biggest potential contributor to rising sea levels due to glacial meltwater. Until now, however, scientists’ attention has mostly focused on the ice sheet’s aquamarine lakes and on monster chunks of ice that slide into the ocean to become icebergs.
The “warming hiatus” over the past 15 years has been caused in part by small volcanic eruptions. Scientists have known volcanoes cool the atmosphere because of the sulfur dioxide that is expelled during eruptions. Droplets of sulfuric acid that form when the gas combines with oxygen in the upper atmosphere can persist for many months, reflecting sunlight away from Earth and lowering temperatures at the surface and in the lower atmosphere.
On a day when much of the U.S. struggled with bone-chilling cold, federal meteorologists said America's weather in 2014 wasn't really that bad. They announced Thursday that the U.S. average temperature in 2014 was half a degree warmer than normal and weather was less disastrous and drought-struck than previous years.
A third of oil reserves, half of gas reserves and over 80% of current coal reserves globally should remain in the ground and not be used before 2050 if global warming is to stay below the 2 C target agreed by policy makers, according to new research by the UCL Institute for Sustainable Resources.
The rate at which carbon emissions warmed Earth's climate almost 56 million years ago resembles modern, human-caused global warming much more than previously believed but involved two pulses of carbon to the atmosphere, researchers at the Univ. of Utah, the Univ. of Michigan and three other universities found.
Cities like Miami are all too familiar with hurricane-related power outages. But a Johns Hopkins Univ. analysis finds climate change will give other major metro areas a lot to worry about in the future. Johns Hopkins engineers created a computer model to predict the increasing vulnerability of power grids in major coastal cities during hurricanes.
A rare weather phenomenon at the Grand Canyon had visitors looking out on a sea of thick clouds just below the rim. The total cloud inversion is expected to hang inside the canyon throughout Thursday.
Off the West Coast of the United States, methane gas is trapped in frozen layers below the seafloor. New research from the University of Washington shows that water at intermediate depths is warming enough to cause these carbon deposits to melt, releasing methane into the sediments and surrounding water.