ORONO – A proposed federally funded research project on abrupt climate change that would be based at the University of Maine has cleared its highest hurdle.

Late last week, the Senate Appropriations Committee approved $1.6 million for research on abrupt climate change, a growing field in which scientists study ancient ice and sediment samples to find patterns in the world’s climate.

Several of the field’s leading researchers, including George Denton and Paul Mayewski, are based at UMaine.

Billions of dollars in federal research money currently goes toward studying the causes of long-term climate changes, in which temperatures rise or fall a few degrees over decades and centuries. But no such federal research program has existed specifically to examine abrupt climate change, in which temperatures can drop or spike several degrees over just a few years.

Most of the current research funding is devoted to studying the long-term impact of greenhouse gases from cars and factories, which most scientists believe are responsible for altering the world’s climate by a degree or two over the last few decades.

Recently, scientists have proven, through the study of the ancient geological record, that the Earth’s climate at times has shifted by as much as 15 degrees in a decade or less. The causes of these abrupt changes are unknown.

When Europe’s climate abruptly changed around 1300, plunging the continent into a centuries-long cold period known as the Little Ice Age, crops failed and the bubonic plague killed thousands of people. Ancient floods and droughts that destroyed civilizations may also have links to abrupt climate change.

The impacts of a similar change on modern agriculture and energy supplies could be disastrous, particularly if global warming caused by human activity combines with whatever natural factors have created abrupt climate changes in the past.

Last December, the National Academy of Sciences issued a report saying that the topic needs “immediate study.”

Understanding what causes abrupt climate change, and how natural climate shifts interact with man-made climate change will be crucial to predicting the future of the world’s climate, it said.

Thousands of ice and sediment samples have been taken in the Northern Hemisphere to support abrupt climate change hypotheses, such as variations in solar radiation or shifts in ocean currents. But few records exist for the Southern Hemisphere, particularly its temperate regions. Currently, scientists aren’t even sure whether abrupt climate change is a worldwide or regional phenomenon, Denton said Monday.

If the funding receives final approval in Congress, research teams led by UM scientists will head to New Zealand, Chile and Argentina to take ice and sediment cores, as well as study the Southern Hemisphere’s geological and botanical histories for clues.

The $1.6 million would cover the cost of several expeditions and pay for the expensive analysis of the samples, Denton said.

“As soon as we get the money, we’ll be off,” he said.

Denton has high hopes that Congress also will approve a separate abrupt climate change research project, by appropriating another $60 million over six years, to be shared among a consortium of universities. Maine’s Climate Change Institute would likely lead that massive research effort.

Both Sens. Olympia Snowe and Susan Collins have actively supported funding for abrupt climate change research, Denton said.

Last year, the $60 million had been included in the Senate’s version of an energy bill, but the funding was lost, primarily due to proposals for oil drilling in Alaska’s Arctic National Wildlife Refuge, which were attached to the same legislation.

This year, the proposal has been added to the energy bill currently under consideration. With the recent blackout in the Midwest and parts of New England and Canada, Washington insiders say that chances are good for a 2003 approval of the bill in some form.