(CNN) -- An international team of researchers plans to head to Antarctica later this year to begin a four-year project exploring some of the last uncharted regions on Earth.
An international team of scientists is heading to Antarctica to study hidden areas of the continent.
The project involving an international team of scientists will reveal what lies beneath the thick polar ice sheet and, they hope, unveil clues about climate change.
The Aurora and Wilkes Subglacial Basins -- an area equivalent to half the size of the United States -- include mountains, valleys, and lakes, all covered in ice that is rapidly melting into the sea, said Professor Martin Siegert of the University of Edinburgh, one of the three groups leading the study.
"The satellite observations tell us the ice is losing mass at this moment and we really do need to understand that," Siegert told CNN. "We need to comprehend why the ice sheet is responding in this way."
Siegert and colleagues from the University of Texas at Austin and the Australian Antarctic Division plan to fly over the area in a World War II-era plane, starting in December. They will be based at Australia's Casey Station.
The team chose to use the upgraded DC-3 aircraft because it offers greater fuel efficiency than the heavy cargo planes used in the past, and better range than the lighter planes, which require extra fuel to be flown in.
"We're getting much more science done with less oil using this old airframe with modern engines," said Don Blankenship, a research scientist at the the Institute for Geophysics at UT-Austin.
Siegert said the plane was "optimum" for what the scientists hoped to do: "This is quite a robust aircraft. It's been used in Antarctica quite often."
The previous research covered only about 40 percent of the ice sheet and stopped in the 1970s, Siegert said.
"I guess everyone thought we'd return one day," he said. "I don't think anybody realized it would take us 30 years."
The research can resume now, he said, because the Australians built an airstrip near Casey that they can use for the project, Siegert said.
As they fly over the area, the researchers plan to use high-resolution radar and other instruments to measure the thickness of the ice and the composition, density and texture of the rocks beneath it.
The findings will help them analyze past climate change over thousands of years and also forecast sea level changes.
"The data that we collect should provide a lot more detail of what caused past climate shifts, why there appears to be more ice loss from glaciers at present, and give us real clues to what may happen in the coming decades," Siegert said.
Funding for the project comes from Britain's Natural Environmental Research Council, the U.S. National Science Foundation, the Australian Antarctic Division and UT-Austin.
Charting of the areas will happen over three Antarctic summers, beginning in December with the eastern section. That area is believed to have the thickest ice on the continent -- up to 5 kilometers (3 miles) thick.
The chemistry of the thick ice might also solve a mystery about past climate, the researchers said.
Antarctic ice cores have already revealed aspects of the earth's climate dating back 800,000 years. But around 1 million years ago, the earth's climate changed in a way that caused ice ages to come and go much more rapidly than before and scientists have long wondered what caused this shift, the University of Texas said.
The Australian researchers on the project plan to search for sites to drill new ice cores to reveal data even older than 1 million years.