While the summer season usually conjures up images of warm weather and beach trips, summer in Antarctica is certainly not that.

The penguins might enjoy it, but with temperatures ranging from zero to 20 degrees Fahrenheit, sometimes dipping to minus 25, it's enough to make anyone long for the milder winter in State College.

Within the last few weeks, two separate groups of Penn State students and faculty left for barren Antarctica to conduct research, two of the many projects Penn State is spearheading in the effort to understand the pressing issue of climate change.

The projects involve drilling deep ice cores to better understand past climate changes, as well as exploring the large Thwaites Glacier to determine how fast the glacier is moving, a concern because of global warming, said Richard Alley, Evan Pugh professor of geosciences.

Alley, who was a contributing and leading author for two chapters in the recent Intergovernmental Panel on Climate Change (IPCC) report, said Penn State is a "world leader" in ice sheet research.

Across the globe, the polar bear, or the "poster child" for climate change, has been affected by the Arctic Sea ice near Greenland that melted to record lows last summer.

The ice is slowly expanding, but the surface area it covers still remains well below normal levels for this time of year, Alley said.

"The minimum reached was way smaller than the long-term average ... by about 40 percent," he said, adding that data for the size of the ice sheet goes back to 1979.

According to the United States Geological Survey, nearly two-thirds of the world's polar bear population could disappear by the mid-21st century if projected changes in Arctic Sea ice are realized.

Michael Mann, associate professor of meteorology, lead author on the previous IPCC report and expert reviewer for the current assessment, said the Greenland ice sheet is a major concern for climate change experts.

"There is some uncertainty in how quickly the Greenland ice sheet will melt as we continue to warm surface temperatures," he said.

"The models may be giving us very conservative answers; they may be indicating that these ice sheets will take far longer to melt than they actually will."

The Greenland ice sheet is of concern for the United States because its melting could lead to widespread flooding of the coastlines, Mann said.

"The southern third of Florida would be gone with 18 feet of sea level rise, which is what would happen if we melted the Greenland ice sheet," he said. "Many scientists feel we could be quite close. If we warm by 2 degrees Celsius ... that amount of warming alone might be enough to ensure the eventual destruction of the Greenland ice sheets."

Scientists differ on how fast the ice sheets could melt, Mann said, with some indicating it could take a few hundred years and others believing it could occur within a century.

The possible results of sea level rise are astonishing: Traditional vacation spots for Pennsylvanians along the shore of New Jersey could be wiped out by erosion.

Additionally, salt water could intrude up to 30 miles inland into the tributaries, Mann said.

Most experts now agree that there is no longer a question of who is causing climate change.

"I think we are very certain that humans play an important role in changing climate," said Klaus Keller, assistant professor of geosciences.

A contributing author to the most recent IPCC assessment, Keller studied the effects of climate change on human populations and how societies become vulnerable to it.

Potential changes in precipitation can lead to drought, thereby decreasing crop production, Keller said.

"Our actions now have implications for future climates for many decades," he said.

Alley's summary of one of IPCC chapters mentions humans burning fossil fuels and other activities as contributing to current and future climate changes.

"This will affect almost everything on the planet, with winners and losers and with losers becoming dominant," Alley said.

Mann said that as a result of climate change, droughts in Pennsylvania could also become more typical.

Warm winters, already seen in the area, could also become more frequent and lead to problems with mosquito-borne diseases, Mann said.

"We could eventually be looking at malaria becoming more prevalent in the United States," he said.

With Europe witnessing extreme heat waves in the past few summers, it is no coincidence that these heat waves are also predicted to become more frequent, even within the United States, Mann said.

Mann recently studied hurricane activity in the Atlantic Ocean and said the early record of cyclones in the area -- thought by some to be inaccurate and falsely evident of an increase in cyclones over time -- was, in fact, reliable.

"This trend does appear to be related to increasing surface temperatures," he said. "We expect to see the temperatures increase in the future ... and continue to see increasing cyclone activity in the Atlantic Ocean."

Keller said climate change has been a gradual process over time, he acknowledged that sudden changes might also occur, but are harder to predict.

"Those strong changes, fast changes, abrupt changes are the ones which have big impacts," he said.

Many scientists agree; as the world continues to deal with climate change and its resulting temperature warming, the periphery results are still not fully known.

As Keller put it: "Expect changes and expect the unexpected."