An international team of researchers may have found what cause a dramatic cooling near the end of the last major Ice Age more than 12,000 years ago. The recently published study, which involved the study of rock melted into carbon spherules, describes evidence of a major cosmic event near the end of the Ice Age. The ensuing climate change forced many species to adapt or die.
According to research taking place at Lawrence Livermore National Laboratory, the distortion of the ancient shoreline and flooding surface of the U.S. Atlantic Coastal Plain are the direct result of fluctuations in topography in the region and could have implications on understanding long-term climate change, according to a new study.
The old saying that "what goes up must come down" doesn't apply to carbon dioxide pollution in the air, which just hit an unnerving milestone. The chief greenhouse gas was measured Thursday at 400 parts per million in Hawaii, a monitoring site that sets the world's benchmark. This was last matched about 2 million years ago, or more, and is more than modern humans have ever encountered.
Researchers studying the origin of cirrus clouds have found that these thin, wispy trails of ice crystals are formed primarily on dust particles and some unusual combinations of metal particles—both of which may be influenced by human activities. The findings are important, scientists say, because cirrus clouds cover as much as one-third of the Earth and play an important role in global climate.
University of Manchester scientists, writing in Nature Geoscience, have shown that natural emissions and manmade pollutants can both have an unexpected cooling effect on the world’s climate by making clouds brighter. Clouds are made of water droplets, condensed on to tiny particles suspended in the air. When the air is humid enough, the particles swell into cloud droplets.
The growing global demand for energy, combined with a need to reduce emissions and lessen the effects of climate change, has increased focus on cleaner energy sources. But what unintended consequences could these cleaner sources have on the changing climate? Researchers at Massachusetts Institute of Technology now have some answers to that question, using biofuels as a test case.
A team from the Smithsonian and the University of Rhode Island has found unsuspected linkages between the oxidation state of iron in volcanic rocks and variations in the chemistry of the deep Earth. Their detailed spectroscopic work has uncovered chemical trends that not only run counter to predictions from recent decades of study, they belie a role for carbon circulating in the deep Earth.
The Environmental Protection Agency has dramatically lowered its estimate of how much of a potent heat-trapping gas leaks during natural gas production. This shift has major implications for a debate that has divided environmentalists, which is whether the recent boom in fracking helps or hurts the fight against climate change.
Recent work by University of Washington climate scientists have provided new insights into how to keep a drink cold on a hot day. Their work shows that, in sultry weather, condensation on the outside of a canned beverage doesn’t just make it slippery: those drops can provide more heat than the surrounding air, meaning the drink would warm more quickly.
The most comprehensive evaluation of temperature change on Earth’s continents over the past 1,000 to 2,000 years indicates that a long-term cooling trend—caused by factors including fluctuations in the amount and distribution of heat from the sun, and increases in volcanic activity—ended late in the 19th century.
A new global-scale modeling study that takes into account nitrogen—a key nutrient for plants—estimates that carbon emissions from human activities on land were 40% higher in the 1990s than in studies that did not account for nitrogen. Most existing models used to estimate global emissions changes based on land use do not have the ability to model nitrogen limitations on plant regrowth.
Using a new laboratory geochemical technique to analyze heavy isotopes of carbon and oxygen in fossil snail shells, scientists have gained insights into an abrupt climate shift that transformed the planet nearly 34 million years ago. At that time, the Earth switched from a warm and high-carbon dioxide "greenhouse" state to the lower-carbon dioxide, variable climate of the modern "icehouse" world.
A Purdue University-led team of researchers discovered sunlit snow to be the major source of atmospheric bromine in the Arctic, the key to unique chemical reactions that purge pollutants and destroy ozone. The team's findings suggest the rapidly changing Arctic climate—where surface temperatures are rising three times faster than the global average—could dramatically change its atmospheric chemistry.
New research indicates that cutting emissions of certain pollutants can greatly slow sea level rise this century. Scientists focussing on emissions of four heat-trapping pollutants—methane, tropospheric ozone, hydrofluorocarbons, and black carbon—found that reductions these pollutants that cycle comparatively quickly through the atmosphere could temporarily forestall the rate of sea level rise by roughly 25 to 50%.
Obama proposed Wednesday spending nearly $35 million in his 2014 budget to refurbish a satellite, nicknamed GoreSat by critics, that's been sitting in storage after it was shelved in 2001, months after Bush took office. It cost about $100 million by then with NASA's internal auditors faulting its cost increases.
For decades, scientists have used sophisticated instruments and computer models to predict the nature of droughts. The majority of these models have steadily predicted an increasingly frequent and severe global drought cycle. But a recent study from a team of researchers in the United State and Australia suggests that one of these widely used tools—the Palmer Drought Severity Index (PDSI)—may be incorrect.
As recently as 5,000 years ago, the Sahara was a verdant landscape, with sprawling vegetation and numerous lakes. The Sahara’s “green” era likely lasted from 11,000 to 5,000 years ago, and is thought to have ended abruptly. Now researchers have found that this abrupt climate change occurred nearly simultaneously across North Africa.
According to a new study by scientists funded by the National Science Foundation (NSF) and at the National Oceanic and Atmospheric Administration (NOAA), clouds over the central Greenland Ice Sheet last July were "just right" for driving surface temperatures there above the melting point. The 2012 melt illustrates the often-overlooked role that clouds play in climate change. Current models don’t do enough, says researchers, to account for their effects.
In 2011, Lake Erie experienced a record-breaking algae bloom that began in the lake's Western region in mid-July and eventually covered an area of 230 square miles. At its peak in October, the bloom had expanded to more than 1,930 square miles, three times greater than any other bloom on record. According to recent research, the bloom was triggered by long-term agricultural practices coupled with extreme precipitation, followed by weak lake circulation and warm temperatures.
Researchers from several universities, AT&T Labs, and the American Museum of Natural History have built new models that show a widespread redistribution of Arctic vegetation. They say their findings predict a massive “greening” in the Arctic, as much as 50% in over the next few decades. This transition will help accelerate climate warming, they add.
Lawrence Berkeley National Laboratory recently hosted an international workshop that brought together top climatologists, computer scientists, and engineers from Japan and the United States to exchange ideas for the next generation of climate models as well as the hyper-performance computing environments that will be needed to process the data from those models. It was the 15th in a series of such workshops that have been taking place around the world since 1999.
It’s not entirely clear what caused the end-Triassic extinction, although most scientists agree on a likely scenario: Over a relatively short period of time, massive volcanic eruptions from a large region known as the Central Atlantic Magmatic Province (CAMP) spewed forth huge amounts of lava and gas, including carbon dioxide, sulfur and methane. Now, a research team has determined that these eruptions occurred precisely when the extinction began, providing strong evidence that volcanic activity did indeed trigger the end-Triassic extinction.
According to new research, models of carbon dioxide in the world’s oceans need to be revised. Trillions of plankton near the surface of warm waters are far more carbon-rich than has long been thought global marine temperature fluctuations could mean that tiny microbes digest double the carbon previously calculated.
With the planet heating up, many scientists seem fairly certain some weather elements like hurricanes and droughts will worsen. But tornadoes have them stumped. As the traditional tornado season nears, scientists have been pondering a simple question: Will there be more or fewer twisters as global warming increases?
Geoengineering, the use of human technologies to alter the Earth's climate system has emerged as a potentially promising way to mitigate the impacts of climate change. But such efforts could present unforeseen new risks. That inherent tension, argue two professors, has thwarted both scientific advances and the development of an international framework for regulating and guiding geoengineering research.