Researchers identify a 'heartbeat' in Earth's climate

Dec 21, 2006
Earth from space

A few years ago, an international team of researchers went to the middle of the Pacific Ocean and drilled down five kilometers below sea level in an effort to uncover secrets about the earth's climate history. They exceeded their expectations and have published their findings in the Dec. 22 edition of the journal Science.

The researchers' drilling produced pristine samples of marine microfossils, otherwise known as foraminifera. Analysis of the carbonate shells of these microfossils, which are between 23 million to 34 million years-old, has revealed that the Earth's climate and the formation and recession of glaciation events in the Earth's history have corresponded with variations in the earth's natural orbital patterns and carbon cycles.

The researchers were particularly interested in these microfossils because they came from the Oligocene epoch, a time in Earth's history known for falling temperatures.

"The continuity and length of the data series we gathered and analyzed allowed for unprecedented insights into the complex interactions between external climate forcing, the global carbon cycle and ice sheet oscillations," said Dr. Jens Herrle, co-author of the paper and a micropaleontology professor at the University of Alberta.

The authors also show how simple models of the global carbon cycle, coupled to orbital controls of global temperature and biological activity, are able to reproduce the important changes observed after the world entered an "ice-house" state about 34 million years ago.

In the early half of the 20th century, Serbian physicist Milutin Milankovitch first proposed that cyclical variations in the Earth-Sun geometry can alter the Earth's climate and these changes can be discovered in the Earth's geological archives, which is exactly what this research team, consisting of members from the United Kingdom, the U.S. and Canada, has done.

"This research is not only concerned with the climate many millions-of-years-ago. Researching and understanding 'extreme' climate events from the geological past allows us to better tune climate models to understand present and future events, and the response to major perturbations of Earth's climate and the global carbon cycle, Herrle added.

Source: University of Alberta

Explore further: Study shows air temperature influenced African glacial movements

add to favorites email to friend print save as pdf

Related Stories

Melting during cooling period

19 hours ago

(Phys.org) —A University of Maine research team says stratification of the North Atlantic Ocean contributed to summer warming and glacial melting in Scotland during the period recognized for abrupt cooling ...

Meteorites yield clues to Martian early atmosphere

13 hours ago

(Phys.org) —Geologists who analyzed 40 meteorites that fell to Earth from Mars unlocked secrets of the Martian atmosphere hidden in the chemical signatures of these ancient rocks. Their study, published ...

Warm US West, cold East: A 4,000-year pattern

22 hours ago

Last winter's curvy jet stream pattern brought mild temperatures to western North America and harsh cold to the East. A University of Utah-led study shows that pattern became more pronounced 4,000 years ago, ...

Better climate predictions within grasp

Apr 14, 2014

that will improve our understanding of the consequences of climate change and could save the global economy up to $30 trillion - has received funding to develop a more detailed design of the technology and identify partners. ...

Scientists explore one of Earth's deepest ocean trenches

Apr 11, 2014

What lives in the deepest part of the ocean—the abyss? A team of researchers funded by the National Science Foundation (NSF) will use the world's only full-ocean-depth, hybrid, remotely-operated vehicle, ...

Recommended for you

New study outlines 'water world' theory of life's origins

Apr 16, 2014

(Phys.org) —Life took root more than four billion years ago on our nascent Earth, a wetter and harsher place than now, bathed in sizzling ultraviolet rays. What started out as simple cells ultimately transformed ...

User comments : 0

More news stories

Melting during cooling period

(Phys.org) —A University of Maine research team says stratification of the North Atlantic Ocean contributed to summer warming and glacial melting in Scotland during the period recognized for abrupt cooling ...

Warm US West, cold East: A 4,000-year pattern

Last winter's curvy jet stream pattern brought mild temperatures to western North America and harsh cold to the East. A University of Utah-led study shows that pattern became more pronounced 4,000 years ago, ...

New clinical trial launched for advance lung cancer

Cancer Research UK is partnering with pharmaceutical companies AstraZeneca and Pfizer to create a pioneering clinical trial for patients with advanced lung cancer – marking a new era of research into personalised medicines ...

More vets turn to prosthetics to help legless pets

A 9-month-old boxer pup named Duncan barreled down a beach in Oregon, running full tilt on soft sand into YouTube history and showing more than 4 million viewers that he can revel in a good romp despite lacking ...