Ancient Arctic Water Cycles are Red Flags to Future Global Warming

August 14, 2006

Ancient plant remains recovered in recent Arctic Ocean sampling cores shows that during a period of carbon dioxide-induced global warming, humidity, precipitation and salinity of the ocean water altered drastically, along with elevated global and regional temperatures, according to a report in the August 10 issue of Nature.

The Arctic Ocean drilling expedition in 2004 allowed scientists to directly measure samples of biological and geological material from the beginning of the Paleocene/Eocene thermal maximum (PETM), a period of rapid, extreme global warming about 55 million years ago. It has given researchers a direct resource of measurable information on global warming — from a time when the overall global temperature was higher and more uniform from the subtropics to the arctic.

The researchers measured carbon and hydrogen isotopes in fossil plants remains and reconstructed the pattern of precipitation and characteristics of the ancient arctic water. “Our results told us a lot about the way that the large-scale water cycle is affected during global warming,” said Mark Pagani, professor of geology and geophysics at Yale and principal author of the study.

The large-scale water cycle refers to the way water vapor is transported from the tropics and subtropics to the poles. “We are all familiar with the rain and storms that occur when warm air masses meet cool northern fronts. During the PETM, temperature differences from the tropics to the poles were lower, reducing rainfall between the subtropics and the North Pole and increasing the amount of water transported to the Arctic,” said Pagani. “It looks like a substantial increase in precipitation led to increased river runoff, lower ocean salinity, and drastically lower oxygen levels in the Arctic Ocean.”

“It is important to realize that the impact of global warming is not just about searing hot summers — it also concerns the water cycle. We need to anticipate big changes in patterns of precipitation as temperatures rise – where and when it will rain and whether or not water resources are available,” said Pagani. “This work is potentially a red flag for things to come.”

Co-author Matthew Huber, an assistant professor of earth and atmospheric sciences at Purdue University's College of Science compared data from the research expedition with complex climate-model simulations to study and predict the effects of greenhouse gases. Their measurements confirm that the carbon dioxide level increase in the PETM was at least twice as large as those previously proposed.

“We now have a pretty good correlation between records of past warmth and higher carbon dioxide concentrations,” Huber said. “What it tells you is that it's not too difficult to push the climate system to a warm state. If you work out the numbers, it's almost identical to what we are expected to do over the next few hundred years.”

Co-authors of the work were Nikolai Pedentchouk at Yale; Appy Sluijs and Henk Brinkhuis at Utrecht University; Gerald Dickens now at Rice University; Stefan Schouten and Jaap Sinninghe Damste at the Royal Netherlands Institute for Sea Research, and “the Expedition 302 Scientists.”

The expedition was an operation of the Integrated Ocean Drilling Program (IODP), an international marine research program primarily funded by the National Science Foundation, and Japan’s Ministry of Education, Culture, Sports, Science and Technology.

Source: Yale University

Explore further: A balanced diet is good for corals too, study finds

Related Stories

A balanced diet is good for corals too, study finds

October 1, 2015

A new study found that a nutrient-rich, balanced diet is beneficial to corals during stressful thermal events. The research led by scientists at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science ...

Surface of the oceans affects climate more than thought

September 30, 2015

The oceans seem to produce significantly more isoprene, and consequently affect stronger the climate than previously thought. This emerges from a study by the Institute of Catalysis and Environment in Lyon (IRCELYON, CNRS ...

New hypothesis on the origin of Mars megafloods

September 30, 2015

A study published in Scientific Reports advances a new explanation for the Martian megafloods: enormous discharges of subterranean water that dug out the biggest flood channels in the solar system over 3000 million years ...

NASA's GPM analyzes Typhoon Dujuan's large rainfall totals

September 30, 2015

The Global Precipitation Measurement or GPM mission core satellite measured the rainfall that Typhoon Dujuan dropped on Taiwan. Highest rainfall totals were over the northwestern Pacific Ocean, and along the eastern coast ...

Highest tides for 18.6 years set for this week in UK

September 29, 2015

Many places along the UK coastline will experience the highest tide for 18.6 years between the 19th and 30th of September, as a result of the co-incidence of a series of astronomical factors.

Recommended for you

History shows more big wildfires likely as climate warms

October 5, 2015

The history of wildfires over the past 2,000 years in a northern Colorado mountain range indicates that large fires will continue to increase as a result of a warming climate, according to new study led by a University of ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.