Focus on Research
Penn State Intercom......October 31, 2002

Uncertainty in West African climate
could have a far-ranging impact

By A'ndrea Messer
Public Information RESEARCH_Jenkins

Plans to meet the outcome of global climate change are under way worldwide, but nowhere is that planning more difficult than in West Africa where the climate has some of the largest signals of change and the climate models have the greatest level of uncertainty, according to meteorologists.

"Adaptability to change is important, but it is hard to determine what to do until we have good climate assessments and can model potential impacts," said Gregory S. Jenkins, associate professor of meteorology. "We know the area is in a trend of less precipitation and higher temperatures, but we do not fully understand why."

Jenkins, working with A.T. Gaye, Cheikh Anta Diop University, Senegal, and A. J. Adedoyin, University of Botswana, Botswana, as part of a U.N. environmental program, is looking at the climate trends and at the global climate models. The climate in West Africa -- the area north of the equator and south of the Sahara desert from Chad in the east to Guinea and Senegal on the west -- has suffered repeated droughts since the 1960s. Recent studies show that the mean rainfall in the Sahel, the area south of the Sahara in West Africa, dropped 37 percent in the period from 1968 to 1997 compared to the period from 1930 to 1960. Temperatures in the region also are warming, with most increases in the spring, summer and autumn months.

"Trying to use observations to extrapolate to the future is not easy," Jenkins said. "Rain occurs in West Africa in the 100 to 1,000 kilometer ranges, but this mesoscale range is too small for the global models. Storms are too small to be noticed by the global climate models."

The solution is to use nested models, regional climate models linked to the global climate models. To do this, the regional models must be tested against observations and then applied to climate change scenarios.

"Eventually, we want the results to go to the end user," Jenkins said. "The water resource planners, health planners and agriculturists who can use the models to plan adaptations to change. These are people who need to know how the timing, patterns and amounts of rain have changed."

Jenkins hopes to begin to answer questions about what is happening to climate in West Africa. Researchers know that when rainfall decreases, the winds of the African Easterly Jet at 10,000 feet decrease in intensity and the winds of the Tropical Easterly Jet at 30,000 feet decrease as well. However, what is not known with climate change is if the rainy season gets shorter, or if less rain falls over the same period of time. Or, does the season begin earlier and end later?

Questions like these are important not just for water and food security, but also for economic development because most power
in the region comes from hydroelectric plants that depend on river flows.

"People in this area frequently lose power once or twice a week," Jenkins said. "Climate changes could seriously impact power supply."

A better understanding of the changes occurring in the region and the way it will alter life in West Africa hopefully will be the result of a better modeling of climate in the area. Before regional plans are formulated to meet future climate change and help the peoples of West Africa adapt to the changes, researchers must understand the dynamics in the region.


A'ndrea Messer can be reached at aem1@psu.edu.

College of Medicine at Hershey Medical Center
awarded $6.9 million grant to improve MRIs

Clearer images of the body's interior may allow physicians to get to the bottom of their patients' medical problems faster.

A $6.9 million grant from the National Institutes of Health's National Institute of Biomedical Imaging and Bioengineering will allow a team of researchers led by Michael B. Smith, professor of radiology, Penn State College of Medicine, to study ultra high field magnetic resonance imaging (MRI) and improve images of the interior of the body.

"Ultimately, this research will lead to improved MRI scanners that will produce clearer, more precise images of the brain, tumors, organs or other structures in the body," Smith said.

MRI is a non-X-ray technique using magnetic fields and radio frequency waves to visualize organs and other structures in the body. The strongest MRI magnet approved for human use is 3 tesla, but most standard high-field MRIs are 1.5 tesla. Investigators at Penn State Milton S. Hershey Medical Center will be studying MR imaging at magnetic field strengths ranging from 3 tesla to 11.7 tesla. A tesla is a measure of magnetic strength; the higher the tesla, the more signal there is to make MR images. However, development of higher magnetic field scanners has thus far been limited by distortion in the images. Interference, or static or radio frequency field distortion causes flaws or black spots -- collectively called "artifacts" -- on MRIs making them difficult to read.

The goal of this grant is to understand why these artifacts occur and develop new techniques for obtaining artifact-free MR images at very high magnetic field strengths.

Grant to study fish, parasites
aimed at controlling disease

A professor in the College of Agricultural Sciences, who has studied the biology of fish in Central Africa's huge Lake Malawi since 1983, has been awarded a $1.6 million, five-year joint grant from the National Science Foundation and National Institutes of Health to research how fish might be managed to control the secondary snail hosts of human parasites.

Jay Stauffer, professor of ichthyology, is the lead researcher on the project. Other grant recipients are Paola Ferreri, associate professor of fisheries management, and Kenneth McKaye, a professor at the Appalachian Environmental Laboratory, University of Maryland System, based in Frostburg, Md.

Stauffer has studied cichlids in Lake Malawi for the past 20 years. Under his guidance, researchers cataloged new species and generated much of the scientific knowledge known about this family of often bright-colored, tropical fishes that are an important food source for Africans and widely available as aquarium specimens in this country.

The funding will allow the research team to look at whether populations of certain cichlids, now diminished by overfishing, can be managed to again control the organisms that cause the disease schistosomiasis. The organisms must live in specific snail species to complete their life cycle and enter human skin through contact in the water. It is hoped that the cichlids can control schistosomiasis by preying on the snails, which have become much more numerous in Lake Malawi as fish numbers have decreased.

In the last two decades, schistosomiasis in humans has reached epidemic proportions in regions bordering Lake Malawi. Schistosomiasis, commonly known as snail fever, occurs in 74 countries and is ranked second only to malaria as a leading cause of human morbidity by a parasitic agent.

Back