According to new research, the ice-free season across the Arctic is getting longer by five days per decade. New analysis of satellite data shows the Arctic Ocean absorbing ever more of the sun’s energy in summer, leading to an ever later appearance of sea ice in the autumn. In some regions, autumn freeze-up is occurring up to 11 days per decade later than it used to.
In recent years, palm oil production has come under fire from environmentalists concerned about the deforestation of land in the tropics to make way for new palm plantations. Now there is a new reason to be concerned about palm oil’s environmental impact, according to researchers at the Univ. of Colorado Boulder.
Volcanic eruptions in the early part of the 21st century have cooled the planet, according to a study led by Lawrence Livermore National Laboratory. This cooling partly offset the warming produced by greenhouse gases. Despite continuing increases in atmospheric levels of greenhouse gases, and in the total heat content of the ocean, global-mean temperatures at the surface of the planet have shown relatively little warming since 1998.
As a range of climate change mitigation scenarios are discussed, Univ. of Washington researchers have found that the injection of sulfate particles into the atmosphere to reflect sunlight and curb the effects of global warming could pose a severe threat if not maintained indefinitely and supported by strict reductions in greenhouse gas emissions.
The Arctic isn't nearly as bright and white as it used to be because of more ice melting in the ocean, and that's turning out to be a global problem, a new study says. With more dark, open water in the summer, less of the sun's heat is reflected back into space. So the entire Earth is absorbing much more heat than expected.
Methane, a key greenhouse gas, has more than doubled in volume in Earth's atmosphere since 1750. Its increase is believed to be a leading contributor to climate change. But where is the methane coming from? Research by a California Institute of Technology atmospheric chemist suggests that losses of natural gas—our "cleanest" fossil fuel—into the atmosphere may be a larger source than previously recognized.
The release of volatile organic compounds from Earth’s forests and smoke from wildfires 3 million years ago had a far greater impact on global warming than ancient atmospheric levels of carbon dioxide, a new Yale Univ. study finds. The research provides evidence that dynamic atmospheric chemistry played an important role in past warm climates, underscoring the complexity of climate change and the relevance of natural components.
The latest observations of Jakobshavn Glacier show that Greenland’s largest glacier is moving ice from land into the ocean at a speed that appears to be the fastest ever recorded. Researchers from the Univ. of Washington and the German Space Agency measured the speed of the glacier in 2012 and 2013.
Insects may thrive in the warmer average temperatures predicted by climate models but are threatened by greater temperature variation also anticipated in many areas around the globe, a Yale Univ.-led study predicts. Scientists have tested the impact of temperature on 38 species of insects. The team coupled that data with historic climate data and climate projections for 2050 to 2059 in order to assess effects of temperature variability.
Scientists studying the atmosphere above Barrow, Alaska, have discovered unprecedented levels of molecular chlorine in the air, a new study reports. Molecular chlorine, from sea salt released by melting sea ice, reacts with sunlight to produce chlorine atoms. These chlorine atoms are highly reactive and can oxidize many constituents of the atmosphere including methane and elemental mercury.
As the world warms, the United States is getting fewer bitter cold spells like the one that gripped much of the nation this week. So when a deep freeze strikes, scientists say, it seems more unprecedented than it really is.
Although few people live in the Western tropical Pacific Ocean region, the remote waters there affect billions of people by shaping climate and air chemistry worldwide. Next week, scientists will head to the region to better understand its influence on the atmosphere—including how that influence may change in coming decades if storms over the Pacific become more powerful with rising global temperatures.
Their effect on the surface of the ocean is negligible, producing a rise of just inches that is virtually imperceptible on a turbulent sea. But internal waves, which are hidden entirely within the ocean, can tower hundreds of feet, with profound effects on the Earth’s climate and on ocean ecosystems.
Pine Island Glacier is one of the biggest routes for ice to flow from Antarctica into the sea. The floating ice shelf at the glacier’s tip has been melting and thinning for the past four decades, causing the glacier to speed up and discharge more ice. Understanding this ice shelf is a key for predicting sea-level rise in a warming world.
Researchers at the Univ. of Utah have discovered a new aquifer in the Greenland Ice Sheet that holds liquid water all year long in the otherwise perpetually frozen winter landscape. The aquifer is extensive, covering 27,000 square miles and could figure significantly in understanding the contribution of snowmelt and ice melt to rising sea levels.
A dozen research papers in a recent special issue of the journal Climate Change are devoted to the topic of geoengineering. They include the most detailed description yet of the proposed Oxford Principles to govern geoengineering research, as well as surveys on the technical hurdles, ethics and regulatory issues related to deliberately manipulating the planet’s climate.
Using a new isotope technique and deep sea corals gathered near the Hawaiian Islands, a Lawrence Livermore National Laboratory scientist, in collaboration with Univ. of California Santa Cruz colleagues, has determined that a long-term shift in nitrogen content in the Pacific Ocean has occurred as a result of climate change. This shift is similar to major paleoceanographic transitions in the sedimentary record.
Interplay between genes and the environment has been pondered at least since the mid-1800s. But until the arrival of modern genomic sequencing tools, it was hard to measure the extent that the environment had on a species’ genetic makeup. Now, researchers studying fruit flies that live on opposite slopes of a unique natural environment known as “Evolution Canyon” show the driving force in the gene pool is largely the environment.
Scientists from the Univ. of Toronto have discovered a novel chemical lurking in the atmosphere that appears to be a long-lived greenhouse gas (LLGHG). The chemical—perfluorotributylamine (PFTBA)—is the most radiatively efficient chemical found to date, breaking all other chemical records for its potential to affect climate.
Two German researchers have used a simple energy balance analysis to explain how the Earth’s water cycle responds differently to heating by sunlight than it does to warming due to a stronger atmospheric greenhouse effect. This difference, their work shows, implies that reflecting sunlight to reduce temperatures may have unwanted effects on the Earth’s rainfall patterns.
At high pressures and low temperatures, such as those in the deep oceans, carbon dioxide occurs as a liquid that is denser than seawater. Researchers in England have identified regions beneath the oceans where the igneous rocks of the upper ocean crust could safely store very large volumes of carbon dioxide.
Hard-to-predict sudden changes to Earth's environment are more worrisome than climate change's bigger but more gradual impacts, a panel of scientists advising the federal government concluded Tuesday. The 200-page report by the National Academy of Sciences looked at warming problems that can occur in years instead of centuries. The report repeatedly warns of potential "tipping points" where the climate passes thresholds.
A new study reveals how pollution causes thunderstorms to leave behind larger, deeper, longer lasting clouds. Appearing in the Proceedings of the National Academy of Sciences, the results solve a long-standing debate and reveal how pollution plays into climate warming. The work can also provide a gauge for the accuracy of weather and climate models.
According to recent Princeton Univ.-led research that simulated an emissions-free Earth, the carbon dioxide already in the atmosphere could continue to warm our planet for hundreds of years, even if emission came to a sudden halt. The study suggests that it might take a lot less carbon than previously thought to reach the global temperature scientists deem unsafe.
For years scientists have intensely argued over whether increases of potent methane gas concentrations in the atmosphere, from about 5,000 years ago to the start of the industrial revolution, were triggered by natural causes or human activities. A new study suggests the increase in methane likely was caused by both.