Atmospheric

Extreme weather is more common than ever. EPA, CC BY-NC By Mark Maslin, University College London Climate change is one of the few scientific theories that makes us examine the whole basis of modern society. It is a challenge that has politicians arguing, sets nations against each other, queries individual lifestyle choices, and ultimately asks questions about humanity’s relationship with the rest of the planet. The Intergovernmental Panel on Climate Change published its synthesis report on November 2, a document that brings together the findings from the IPCC’s three main working groups. It…

A man relaxes in some decidedly un-Scottish weather outside the venue for this year's Commonwealth Games in Glasgow. AAP Image/ Dave Hunt By Andrew King, University of Melbourne; David Karoly, University of Melbourne and Sophie Lewis, Australian National University It’s clear: 2014 has been a scorcher. As well as probably being the hottest year on record globally, regional and local climate records have tumbled too. Australia recently had its hottest spring on record, beating the previous record set only last year. Human influences on the climate very likely played a significant role in this…

The rate at which carbon emissions might be warm Earth's climate today are a lot like the past. 56 million years in the past. The authors of a new paper believe the Paleocene-Eocene thermal maximum, or PETM, can provide clues to the future of modern climate change. The good news: Earth and most species survived warming that was a lot more pronounced  -  up to 15 degrees Fahrenheit - than even the most dour predictions being made now. The bad news: It took 200,000 years to get back to what we now consider normal. The authors report in Nature Geoscience that carbonate or limestone…

A new analysis to be presented next week at the American Geophysical Union's Fall Meeting in San Francisco says that extreme climate and weather events such as record high temperatures, intense downpours and severe storm surges are more common in many parts of the world. It's hard to be sure. High quality weather records only go back about 30 years and even suspect quality records only go back 100, so there is inference between modern record-keeping and the data trapped in tree rings and ice cores from ancient times. The Intergovernmental Panel on Climate Change (IPCC), stung by…

Braving the eye of the bomb. Danny Lawson/PA By Edward Hanna, University of Sheffield A dramatically-named “weather bomb” exploded across the UK in the past week, bringing winds gusting up to 144 mph on outlying islands. But despite the cool name these “bombs” are more common than you might think. The UK’s forecasting agency the Met Office defines a weather bomb as an intense low-pressure system with an atmospheric pressure in its core that drops at least 24 millibars in 24 hours. Their charts indeed show an impressive low-pressure system tracking slowly eastwards between southern Greenland…

Ten years after carbon emissions happen, the warming effect is maximized. Methane is even quicker, and far more potent, though it also disappears much more rapidly. CO2 emissions certainly matter over the long haul but they are important in the short term also, and that means there is some good news. Though China, the world's top polluter, has been allowed to emit unchecked until 2030, the United States is back at early 1990s levels of CO2 emissions and the biggest source of industrial emissions, energy from coal, is back at early 1980s levels, thanks to natural gas. Climate models will need…

Each year, the biosphere balances its atmospheric budget: The carbon dioxide absorbed by plants in the spring and summer as they convert solar energy into food is released back to the atmosphere in autumn and winter. Levels of the greenhouse gas fall and rise with growth and harvesting. Obviously we grow more food than 50 years ago and so that budget has gotten bigger. Over the last five decades, the swing has grown nearly 50 percent in the Northern Hemisphere. Now, new research shows that humans and their crops have a lot to do with it, highlighting the profound impact people have on…

Iowa corn farmers have a lot of clout during the political cycle in America. Former US Vice-President Al Gore even sided with environmentalists and embraced ethanol - which all of science said was a bad idea - and later acknowledged it was just to appeal to Iowa. They help pick presidents and now it turns out that their 2.2 billion bushels of corn are helping to save the planet too. Each year in the Northern Hemisphere, levels of atmospheric carbon dioxide drop in the summer and during the last 50 years, the size of this seasonal swing has increased by as much as half, for reasons…

The Moderate Resolution Imaging Spectroradiometer (MODIS) instrument that flies aboard NASA's Aqua satellite captured a visible picture of Tropical Storm Adjali on Nov. 19th at 9:05 UTC (1:05 A.M. Pacific) curving to the southwest on its trek through the Southern Indian Ocean. The MODIS image showed that the storm began curving to the southwest, and despite slight weakening, thunderstorms circled around the low-level center. Adjali was curving to the southwest as it continued to move along the extreme southwestern edge of an equatorial ridge (elongated area) of high pressure, located…

Volcanoes have long been known to have an impact on climate - the 1815 Tambora volcanic eruption is famous for its impact on climate worldwide, making 1816 the 'Year Without a Summer'. Maybe they are the reason global warming has not taken off the way climate researchers estimated it would. Sulfur dioxide gas that eruptions expel might be cooling the atmosphere more than previously thought, contributing to the recent slowdown in global warming, according to a new study. Droplets of sulfuric acid that form when sulfur dioxide gas combines with oxygen in the upper atmosphere can remain for…