Atmospheric

Scientists at the University of Liverpool have found that natural variability in the earth’s atmosphere could be masking the overall effect of global warming in the North Atlantic Ocean. Scientists have said that surface temperatures around the globe have risen over the last 30 years in accord with global warming. New data, however, shows that heat stored in the North Atlantic Ocean has a more complex pattern than initially expected, suggesting that natural changes in the atmosphere also play a role. A coalition of researchers at the University of Liverpool and Duke University analyzed 50…

Rainfall data from a NASA satellite show that summertime storms in the southeastern United States shed more rainfall midweek than on weekends. Why would that be? Thomas Bell, an atmospheric scientist at NASA's Goddard Space Flight Center, says air pollution is the culprit because it also peaks mid-week. The link between rainfall and the day of the week is evident in data from NASA's Tropical Rainfall Measuring Mission satellite, known as TRMM. Midweek storms tend to be stronger, drop more rain and span a larger area across the Southeast compared to calmer and drier weekends. To find out…

It used to be that El Nino was a predictable phenomenon that explained odd weather changes but recent global warming studies minimized its impact - everything was global warming instead. Now, it seems, El Nino is back in atmospheric fashion. Scientists have known about El Niño weather fluctuations over a large portion of the world since the early 1950s. They occur in cycles every three to seven years, changing rain patterns that can trigger flooding as well as drought. Siegfried Schubert of NASA's Goddard Space Flight Center in Greenbelt, Md., and his colleagues studied the impact that El…

In transportation, road traffic contributes the most to global warming, aviation is second, railways are negligible and shipping actually has a net cooling effect on the earth’s climate, according to a study published recently. But we can't simply switch to shipping and cure global warming. Shipping emits large portions of SO2 and NOx, which both have cooling effects, but this effect will diminish as the gases don’t live long in the atmosphere. After a few decades, the long-lived CO2 will dominate, giving shipping a warming effect in the long run. Both SO2 and NOx also have other impacts…

Climatologists at the NASA Goddard Institute for Space Studies (GISS) in New York City released an analysis showing that 2007 tied with 1998 for Earth’s second warmest year in a century. 2006 was fifth in that period. There will be some issue with accuracy. The researchers used temperature data from weather stations on land, satellite measurements of sea ice temperature since 1982 and data from ships for earlier years. The greatest warming in 2007 occurred in the Arctic, and neighboring high latitude regions. Global warming has a larger affect in polar areas, as the loss of snow and ice…

Are we running out of helium? Lee Sobotka, professor of chemistry and physics at Washington University in St. Louis, says it is being depleted so rapidly in the world’s largest reserve, outside of Amarillo, Tex., that supplies are expected to be gone there within the next eight years. The helium we have on earth is not readily renewable, it has been built up over billions of years from the decay of natural uranium and thorium. The decay of these elements proceeds at a super-snail’s pace. It will impact more than balloons and kids' voices, Sobotka says. “Helium’s use in science is…

An international study investigating the carbon sink capacity of northern terrestrial ecosystems discovered that the duration of the net carbon uptake period (CUP) has on average decreased due to warmer autumn temperatures. Net carbon uptake of northern ecosystems is decreasing in response to autumnal warming according to findings published in Nature. The carbon balance of terrestrial ecosystems is particularly sensitive to climatic changes in autumn and spring. Over the past two decades autumn temperatures in northern latitudes have risen by about 1.1 °C with spring temperatures up by 0.8 °C…

Record-breaking amounts of ice-free water have deprived the Arctic of more of its natural "sunscreen" than ever in recent summers. The effect is so pronounced that sea surface temperatures rose to 5 C above average in one place this year, a high never before observed, says the oceanographer who has compiled the first-ever look at average sea surface temperatures for the region. Such superwarming of surface waters can affect how thick ice grows back in the winter, as well as its ability to withstand melting the next summer, according to Michael Steele, an oceanographer with the University of…

Methane, a potent greenhouse gas, is emitted in great quantities as bubbles from seeps on the ocean floor near Santa Barbara. About half of these bubbles dissolve into the ocean, but the fate of this dissolved methane remains uncertain. Researchers at the University of California, Santa Barbara have discovered that only one percent of this dissolved methane escapes into the air -- good news for the Earth's atmosphere. Coal Oil Point (COP), one of the world's largest and best studied seep regions, is located along the northern margin of the Santa Barbara Channel. Thousands of seep fields exist…

The climatic event El Niño, literally “the Baby Jesus”, was given its name because it generally occurs at Christmas time along the Peruvian coasts. This expression of climatic variability, also called El Niño Southern Oscillation (ENSO), results from a series of interactions between the atmosphere and the tropical ocean. It induces drought in areas that normally receive abundant rain and, conversely, heavy rainfall and floods in usually arid desert zones. Scientists term this phenomenon a “quasi-cyclic” variation because its periodicity, which varies from 2 to 7 years, shows no regular time…