Warming of planet will affect storms differently in Northern and Southern hemispheres

MIT study finds that more intense storms will occur in the Southern Hemisphere

2010-10-26

(Press-News.org) CAMBRIDGE, Mass. -- Weather systems in the Southern and Northern hemispheres will respond differently to global warming, according to an MIT atmospheric scientist's analysis that suggests the warming of the planet will affect the availability of energy to fuel extratropical storms, or large-scale weather systems that occur at Earth's middle latitudes. The resulting changes will depend on the hemisphere and season, the study found.

More intense storms will occur in the Southern Hemisphere throughout the year, whereas in the Northern Hemisphere, the change in storminess will depend on the season — with more intense storms occurring in the winter and weaker storms in the summer. The responses are different because even though the atmosphere will get warmer and more humid due to global warming, not all of the increased energy of the atmosphere will be available to power extratropical storms. It turns out that the changes in available energy depend on the hemisphere and season, according to the study, published Monday in the Proceedings of the National Academy of Sciences.

Fewer extratropical storms during the summer in the Northern Hemisphere could lead to increased air pollution, as "there would be less movement of air to prevent the buildup of pollutants in the atmosphere," says author Paul O'Gorman, the Victor P. Starr Career Development Assistant Professor of Atmospheric Science in MIT's Department of Earth, Atmospheric and Planetary Sciences. Likewise, stronger storms year-round in the Southern Hemisphere would lead to stronger winds over the Antarctic Ocean, which would impact ocean circulation. Because the ocean circulation redistributes heat throughout the world's oceans, any change could impact the global climate.

O'Gorman's analysis examined the relationship between storm intensity and the amount of energy available to create the strong winds that fuel extratropical storms. After analyzing data compiled between 1981 and 2000 on winds in the atmosphere, he noticed that the energy available for storms depended on the season. Specifically, it increased during the winter, when extratropical storms are strong, and decreased during the summer, when they are weak.

Because this relationship could be observed in the current climate, O'Gorman was confident that available energy would be useful in relating temperature and storminess changes in global-warming simulations for the 21st century. After analyzing these simulations, he observed that changes in the energy available for storms were linked to changes in temperature and storm intensity, which depended on the season and hemisphere. He found that available energy increased throughout the year for the Southern Hemisphere, which led to more intense storms. But for the Northern Hemisphere, O'Gorman observed that available energy increased during the winter and decreased during the summer.

This makes sense, O'Gorman says, because the changes in the strength of extratropical storms depend on where in the atmosphere the greatest warming occurs; if the warming is greatest in the lower part of the atmosphere, this tends to create stronger storms, but if it is greatest higher up, this leads to weaker storms. During the Northern Hemisphere summer, the warming is greatest at higher altitudes, which stabilizes the atmosphere and leads to less intense storms.

Although the analysis suggests that global warming will result in weaker Northern Hemisphere storms during the summer, O'Gorman says that it's difficult to determine the degree to which those storms will weaken. That depends on the interaction between the atmosphere and the oceans, and for the Northern Hemisphere, this interaction is linked to how quickly the Arctic Ocean ice disappears. Unfortunately, climate scientists don't yet know the long-term rate of melting.

INFORMATION: Source: "Understanding the varied response of the extratropical storm tracks to climate change," by Paul A. O'Gorman. Proceedings of the National Academy of Sciences, 25 October, 2010

ELSE PRESS RELEASES FROM THIS DATE:

World's largest, most complex marine virus is major player in ocean ecosystems: UBC research

2010-10-26

UBC researchers have identified the world's largest marine virus--an unusually complex 'mimi-like virus' that infects an ecologically important and widespread planktonic predator. Cafeteria roenbergensis virus has a genome larger than those found in some cellular organisms, and boasts genetic complexity that blurs the distinction between "non-living" and "living" entities. "Virus are classically thought of small, simple organisms in terms of the number of genes they carry," says UBC professor Curtis Suttle, an expert in marine microbiology and environmental virology ...

Barber-based intervention may help black men better control high blood pressure

2010-10-26

Black men who are offered a blood pressure check while at the barbershop appear more likely to improve control of hypertension, according to a report posted online today that will be published in the February 28 print issue of Archives of Internal Medicine, one of the JAMA/Archives journals. "Uncontrolled hypertension is one of the most important causes of premature disability and death among non-Hispanic black men," the authors write as background information in the article. "Compared with black women, men have less frequent physician contact for preventive care and ...

Primary care physicians may earn lowest hourly wages

2010-10-26

Clinician's wages appear to vary significantly across physician specialties and are lowest for those in primary care, according to a report in the October 25 issue of Archives of Internal Medicine, one of the JAMA/Archives journals. "Numerous studies have documented substantial income disparities between primary care and other physician specialties. Such disparities may impede health care reform by undermining the sustainability of a vigorous primary care workforce," the authors write as background information in the article. Comparing clinicians' annual income may not ...

Active ingredient levels vary among red yeast rice supplements

2010-10-26

Different formulations of red yeast rice, a supplement marketed as a way to improve cholesterol levels, appear widely inconsistent in the amounts of active ingredients they contain, according to a report in the October 25 issue of Archives of Internal Medicine, one of the JAMA/Archives journals. In addition, one in three of 12 products studied had detectable levels of a potentially toxic compound. "Chinese red yeast rice, also known as Hong Qu, is a medicinal agent and food colorant made by culturing a yeast, Monascus purpureus, on rice," the authors write as background ...

Heavy smoking in midlife may be associated with dementia in later years

2010-10-26

Heavy smoking in middle age appears to be associated with more than double the risk for Alzheimer's disease and other forms of dementia two decades later, according to a report posted online today that will be published in the February 28 print issue of Archives of Internal Medicine, one of the JAMA/Archives journals. Current estimates suggest smoking is responsible for several million deaths per year from causes such as heart disease and cancer, according to background information in the article. Although smoking increases risks of most diseases and of death, some studies ...

Complications after endoscopies may be underestimated using standard reporting procedures

2010-10-26

Hospital visits following outpatient gastrointestinal endoscopies may be more common than previously estimated, according to a report in the October 25 issue of Archives of Internal Medicine, one of the JAMA/Archives journals. About 15 to 20 million endoscopic procedures, in which a clinician uses a tube-like instrument called an endoscope to see inside a patient's body, are performed each year in the United States, according to background information in the article. However, data on the safety of these procedures and the complications occurring afterward are limited. ...

Physicians agree Medicare reimbursement is flawed, disagree on how to reform it

2010-10-26

A national survey finds most physicians believe Medicare reimbursement is inequitable, but there appears to be little consensus regarding proposed reforms, according to a report in the October 25 issue of Archives of Internal Medicine, one of the JAMA/Archives journals. "Across the political spectrum, there is general agreement that the cost of health care has risen to untenable levels and is threatening the future of Medicare and the economic well-being of the United States," the authors write as background information in the article. Clinicians account for one-fifth ...

Blood pressure checks performed by barbers improve hypertension control in African-American men

2010-10-26

LOS ANGELES (STRICTLY EMBARGOED UNTIL 3 PM CDT ON OCT. 25, 2010) – Neighborhood barbers, by conducting a monitoring, education and physician-referral program, can help their African-American customers better control high blood pressure problems that pose special health risks for them, a new study from the Cedars-Sinai Heart Institute shows. The study -- the first to subject increasingly popular barbershop-based health programs to a scientific scrutiny with randomized, controlled testing -- demonstrates the haircutters' heart health efforts work well enough that they ...

Bicarbonate adds fizz to players' tennis performance

2010-10-26

Dietary supplementation with sodium bicarbonate (baking soda) on the morning of a tennis match allows athletes to maintain their edge. A randomized, controlled trial reported in BioMed Central's open access Journal of the International Society of Sports Nutrition found that those players who received the supplement showed no decline in skilled tennis performance after a simulated match. Chen-Kang Chang from the National Taiwan College of Physical Education, Taiwan, worked with a team of researchers to carry out the study. He said, "We found that sodium bicarbonate supplementation ...

Huge amber deposit discovered in India

2010-10-26

Those who are proud to have a piece of amber that holds a little animal trapped in it maybe should not continue to read this. For what can be seen in the millions of years-old tree resin is almost always just a paper-thin façade. If sliced down the middle, you would find no more than a hollow space covered in some sort of "insect photo wallpaper." This does not apply to the amber Bonn paleontologist Professor Dr. Jes Rust and his colleagues have been looking at for two years. The lumps that resemble herbal cough drops are "full of it," containing numerous insect bodies, ...

Warming of planet will affect storms differently in Northern and Southern hemispheres

ELSE PRESS RELEASES FROM THIS DATE:

LAST 30 PRESS RELEASES: