New clues to air circulation in the atmosphereAugust 22, 2008Air circulates above the Earth in four distinct cells, with two either side of the equator, says new research out today (21 August) in Science. The new observational study describes how air rises and falls in the atmosphere above the Earth's surface, creating the world's weather. This process of atmospheric circulation creates weather patterns and influences the climate of the planet. It is important to understand these processes in order to predict weather events, and to improve and test climate models. Previous theories have claimed that there are just two large circular systems of air in the atmosphere, one either side of the equator. These theories suggested that air rises at the equator and then travels towards either the north or south polar regions, where it falls. The new research suggests instead that there are two cells in both the northern and southern hemispheres. In the first cell, air rises at the equator and then falls in the subtropics. In the second cell, air rises in the mid-latitudes - approximately 30 to 60 degrees north and south of the equator - and then falls in the polar regions. The researchers say that this second cell of rising air is a mechanism responsible for setting the distribution of temperature and winds in the mid-latitudes which has not been fully appreciated before. The mid-latitudes include the UK, Europe and most of the United States. Dr Arnaud Czaja from Imperial College London's Department of Physics and the Grantham Institute for Climate Change, one of the authors of the new research, explains: "Our model suggests that there is a second cell of air in each hemisphere which is characterised by air rising, clouds forming, storms developing and other processes associated with moisture in the air occurring in the mid-latitudes." Current theories to describe weather patterns in the mid-latitudes do not take these moisture-based processes into consideration. Dr Czaja argues that these theories are therefore incomplete, and that water vapour plays as much of an important role in the weather systems of the mid-latitudes as it does in the tropics, where it is a well-documented driver of weather events. The research team carried out their study by conducting new analyses of extensive meteorological data. Dr Czaja says that he hopes the research will lead to a more detailed understanding of how air circulation in our atmosphere works, and how it affects the weather: "With more attention than ever before being focused on understanding our planet's climate, weather systems and atmosphere, it's important that scientists challenge their own assumptions and current theories of how these complex processes work. I think our study sheds new light on the driving forces behind the weather in the mid-latitudes," Dr Czaja added. Imperial College London |
|||||||||||||||||||||
| Related Atmosphere Current Events and Atmosphere News Articles Researchers Hail Innovative Plan to Save Rainforest, Reduce Greenhouse Gas Emissions An innovative proposal by the Ecuadorian government to protect an untouched, oil rich region of Amazon rainforest is a precedent-setting and potentially economically viable approach, says a team of environmental researchers from the University of Maryland, the World Resources Institute and Save America's Forests. Texas A&M prof to predict weather on Mars Is there such a thing as "weather" on Mars? There are some doubts, considering the planet's atmosphere is only 1 percent as dense as that of the Earth. Carbon atmosphere discovered on neutron star Evidence for a thin veil of carbon has been found on the neutron star in the Cassiopeia A supernova remnant. This discovery, made with NASA's Chandra X-ray Observatory, resolves a ten-year mystery surrounding this object. Report on US-China collaboration on carbon capture and sequestration Lawrence Livermore National Laboratory's Julio Friedmann, in collaboration with the Center for American Progress, the Asia Society Center and with partner Monitor Group, today released the report, "A Roadmap for U.S.-China Collaboration on Carbon Capture and Sequestration." NRL sensor provides critical space weather observations Launched from Vandenberg Air Force Base, Calif., aboard an United Launch Alliance Atlas V launch vehicle, Oct. 18, 2009, the Special Sensor Ultraviolet Limb Imager (SSULI) developed by NRL's Space Science Division and Spacecraft Engineering Department offers a first of its kind technique for remote sensing of the ionosphere and thermosphere from space. Iron controls patterns of nitrogen fixation in the Atlantic Scientists including researchers from the National Oceanography Centre, Southampton and the University of Essex have discovered that interactions between iron supply, transported through the atmosphere from deserts, and large-scale oceanic circulation control the availability of a crucial nutrient, nitrogen, in the Atlantic. VERITAS telescopes help solve 100-year-old mystery: The origin of cosmic rays Nearly 100 years ago, scientists detected the first signs of cosmic rays - subatomic particles (mostly protons) that zip through space at nearly the speed of light. Iowa State researchers contribute to discovery of gamma rays from starburst galaxy Iowa State University astrophysicists contributed to the recent discovery that a galaxy quickly creating new stars is also a source of high energy gamma rays. 'Ultra-primitive' particles found in comet dust Dust samples collected by high-flying aircraft in the upper atmosphere have yielded an unexpectedly rich trove of relicts from the ancient cosmos, report scientists from the Carnegie Institution. Starburst galaxy sheds light on longstanding cosmic mystery An international collaboration that includes scientists from the University of Delaware's Bartol Research Institute in the Department of Physics and Astronomy has discovered very-high-energy gamma rays in the Cigar Galaxy (M82), a bright galaxy filled with exploding stars 12 million light years from Earth. More Atmosphere Current Events and Atmosphere News Articles |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||