Ancient Arctic Water Cycles are Red Flags to Future Global Warming

Aug 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: The Albian Gap, salt rock, and a heated debate

Related Stories

Peat moss, a necessary bane

May 21, 2015

The temperature balance on Earth may be dependent on a conspicuous creation that sours life for everyone around, guzzles more than a sponge and produces lots of offspring that behave likewise. And you thought ...

Oceanographer publishes atlas of seafloor volcanoes and deep-ocean life

May 20, 2015

A University of Washington oceanographer has helped create the first full-color photographic atlas of the ocean floor. "Discovering the Deep: A Photographic Atlas of the Seafloor and Ocean Crust" (Cambridge University Press, 2015) was almost a decade in the making and contains more than 500 original illustrations and col ...

How do you measure a sea's level, anyway?

May 19, 2015

There are about 330 million cubic miles of water in the world oceans today, 97% of all the water on the planet. Early in our planet's 4.5 billion year history, water from the atmosphere and from the inte ...

Recommended for you

The Albian Gap, salt rock, and a heated debate

5 hours ago

Salt rock behaves as a fluid and can play a pivotal role in the large-scale, long-term collapse of the world's continental margins. However, the precise way in which this occurs is laced in controversy; nowhere ...

Satellites catch the birth of two volcanic islands

15 hours ago

The birth of a volcanic island is a potent and beautiful reminder of our dynamic planet's ability to make new land. Given the destruction we've seen following natural events like earthquakes and tsunamis in t ...

Uncovering diversity in an invisible ocean world

16 hours ago

Plankton are vital to life on Earth—they absorb carbon dioxide, generate nearly half of the oxygen we breathe, break down waste, and are a cornerstone of the marine food chain. Now, new research indicates ...

User comments : 0

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.