Focus on Research
Penn State Intercom......October 10, 2002

Extensive survey confirms
global warming effect

By Barbara Kennedy
Eberly College of Science

RESEARCH_PostA comprehensive summary has revealed, for the first time, the dramatic extent of disruptions now being experienced by Earth's species as a result of global warming.

The extensive report compiles the results of more than 100 research studies on the effects that recent climate changes have had on animals and plants throughout the world. The international team of researchers included Eric Post, assistant professor of biology, and others at institutions in Australia, France, Germany, Texas, and the United Kingdom.

"We tried to provide the biggest possible picture of what is now happening to the world's species," Post said.

Post said the researchers were somewhat surprised, as the results of the study unfolded before their eyes, to see the extent of the evidence for the impact of Earth's changing climate on species worldwide.

"That anyone can question whether living things are being affected by climate change now seems incredibly dubious itself," he said.

The study ranges from how climate changes are affecting individual animals and plants, such as in the timing of migration, breeding or plant flowering; to local populations of the same species; to communities of species and their interactions within a single habitat; to major redistributions of assemblages of species within entire ecosystems.

"All the major biomes on Earth have been affected by a temperature increase of just a little more than half a degree Celsius -- most of which has occurred during the last two decades," said Post, who described this increase as comparable to the warming that occurs from about 8 a.m. to 9:30 a.m. on a typical spring day. "That such a small change has had such an extensive effect is alarming when you consider that even conservative estimates predict the climate will heat up at least two or three degrees more."

The scientists found that because global climate change is highly variable throughout the world, it is affecting different species and different locations in different ways.

Robins in the Colorado Rockies, for example, who migrate to higher altitudes when climate signals tell them the spring breeding season has arrived, are finding that it is still winter at their higher-elevation breeding sites. "The climate is warming earlier at lower elevations in the Rockies, but at higher elevations the thick winter snow has not yet melted so the robins can't get to the worms and other invertebrates that are their major food source," Post said. "We can expect to see mass deaths in some populations, or years when very few young survive into adulthood."

The researchers also found that early-blooming species of plants now are blooming earlier in the spring, effectively lengthening their blooming period. "An analysis of 50 years of data from Norway on 13 plant species in 137 locations revealed changes directly related to climate in 71 percent of the total, with early-blooming and herbaceous species showing greater reactions to winter warming than late-blooming and woody plants," Post said.

The study reveals that sudden climate events that have an extreme local effect can have significant consequences for groups of local species. "We are seeing evidence in the Sonoran Desert in the Southwestern United States, for example, that just one extreme El Niño event can send a ripple through the biological community, tipping the ecological balance a little bit in favor of one species over another, which can result in a whole new assemblage of species," Post said.

"If climate temperatures increase suddenly instead of gradually, of if we have one exceptionally unusual warm season, or if there is an unforeseen sudden climate change, then past climate history would become irrelevant as a tool for predicting what will happen in the future," Post said. "In addition, some ecological changes could be gradual until it reaches an unknown critical point, at which a sudden catastrophic event could occur. "

Barbara Kennedy can be reached at science@psu.edu.


Grant will bolster graduate
training program to aid rural children

The Department of Communication Sciences and Disorders has received a four-year, $800,000 grant from the U.S. Department of Education for a graduate training program that will help address the needs of children with speech-language and literacy problems, particularly in rural areas.

The Speech Language Literacy Project will provide tuition and stipends for up to 32 students who are pursuing master's degrees in communication sciences and disorders and who plan to become speech-language pathologists. The comprehensive pre-service training program will prepare students to provide high-quality services to children with speech-language disabilities and literacy problems, especially those from culturally and linguistically diverse backgrounds. The grant also enables the department to address the existing shortage of speech-language pathologists, particularly in rural areas.

Gordon Blood, professor and head of the Department of Communication Sciences and Disorders, will serve as principal investigator for the project, which was developed in collaboration with numerous state departments of education; national, regional and local community education agencies; parents and consumer representatives. Constance Dean Qualls and Carol Scheffner Hammer, assistant professors of communication sciences and disorders, will serve as co-directors.


Students overcome
fuel cell barriers

A series of obstacles fell before the onslaught of a University engineering graduate class as it tackled and found solutions to all the barriers preventing development of a hybrid fuel cell automobile using hydrogen fuel cells and battery storage.

"The professors asked the class to solve the problem of hydrogen odorization," said Jamie Weston, graduate student in energy and geoenvironmental engineering. "We quickly came up with a solution and, took the rest of the course to develop our solution and follow the problems as far as we could."

The students -- Mike Sprague, Hui Long, Ramya Venkataraman, Patrick Flynn, Eric Wolfe and Weston -- are all in the Energy and Geoenvironmental Engineering program and took the hands-on fuel science class taught by Alan W. Scaroni, head and professor, Andre Boehman, associate professor, and Sarma V. Pisupati, associate professor in the department.

Hydrogen is a colorless and odorless gas. The government mandates that all flammable gases must have an odor. The chemicals used to add a smell to the gas, limit the possibility of using the hydrogen in a fuel cell because the chemicals often poison the cells.

"We came up with a simple system that removes the odorant with adsorbers and then tests to ensure that all the odorant is removed before sending the hydrogen to solid storage and fuel cell," Weston said.

Fuel cells convert the chemical potential of hydrogen and oxygen to electrical potential with heat and water without burning the hydrogen. For a fuel cell to work, the hydrogen must be ultra pure.

Another problem in the conceptualization of hybrid fuel cell vehicles is hydrogen storage. While it is easily stored as a compressed gas, safety concerns swayed the students to use a technically feasible, solid storage method. The students chose a metal hydride system based on magnesium. The hydrogen in the magnesium hydride is stable up to 554 degrees Fahrenheit, but once heated above that temperature, hydrogen gas is released.

Fuel cells are not the sole energy source in this hybrid automobile. The battery stacks, which may be charged from an outlet in the garage or by the fuel cells are the primary source of power for short trips and in town driving. The batteries also will power the electric heating units that heat up sections of the magnesium hydride, once the battery stack is drained to a certain capacity. Excess energy from the fuel cells will recharge the batteries.

"Batteries are now being reduced in size, so the weight of the batteries and the hydrogen fuel system will not make the car too heavy," Weston said. "Because most of the hydrogen is stored as a solid, the automobile may be as safe as today's cars."

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