Geology Times
Recent News |  Archives |  Tags |  About |  Newsletter |  Submit News |  Earthquakes |  Subscribe to GeologyTimes.com RSS Feed Subscribe


More Articles
The internet was delivered to the masses; parallel computing is not far behindThe internet was delivered to the masses; parallel computing is not far behind

Worker bees 'know' when to invest in their reproductive futureWorker bees 'know' when to invest in their reproductive future

The channel that relaxes DNAThe channel that relaxes DNA

A spectacular landscape of star formationA spectacular landscape of star formation

Cool moleculesCool molecules

Tilted acoustic tweezers separate cells gentlyTilted acoustic tweezers separate cells gently

Study: Earth can sustain more terrestrial plant growth than previously thoughtStudy: Earth can sustain more terrestrial plant growth than previously thought

A breakthrough in imaging gold nanoparticles to atomic resolution by electron microscopyA breakthrough in imaging gold nanoparticles to atomic resolution by electron microscopy

Evolutionary history of honeybees revealed by genomicsEvolutionary history of honeybees revealed by genomics

Bombarded by explosive waves of information, scientists review new ways to process and analyze Big DataBombarded by explosive waves of information, scientists review new ways to process and analyze Big Data

Key to speed? Elite sprinters are unlike other athletes -- deliver forceful punch to groundKey to speed? Elite sprinters are unlike other athletes -- deliver forceful punch to ground

Researchers block plant hormoneResearchers block plant hormone

Hot-spring bacteria reveal ability to use far-red light for photosynthesisHot-spring bacteria reveal ability to use far-red light for photosynthesis

Stem cells reveal how illness-linked genetic variation affects neuronsStem cells reveal how illness-linked genetic variation affects neurons

Proteins: New class of materials discoveredProteins: New class of materials discovered

Abusive leadership infects entire teamAbusive leadership infects entire team

Study suggests hatha yoga boosts brain function in older adultsStudy suggests hatha yoga boosts brain function in older adults

Program earns kudos for improving grades, retaining studentsProgram earns kudos for improving grades, retaining students

Common household chemicals decrease reproduction in mice, study findsCommon household chemicals decrease reproduction in mice, study finds

A self-organizing thousand-robot swarmA self-organizing thousand-robot swarm

Crash-testing rivetsCrash-testing rivets

Scientists discover the miracle of how geckos move, cling to ceilingsScientists discover the miracle of how geckos move, cling to ceilings

Geography matters: Model predicts how local 'shocks' influence U.S. economyGeography matters: Model predicts how local 'shocks' influence U.S. economy

Shrinking dinosaurs evolved into flying birdsShrinking dinosaurs evolved into flying birds

A healthy lifestyle adds years to lifeA healthy lifestyle adds years to life

Do probiotics help kids with stomach bugs?Do probiotics help kids with stomach bugs?

Strict diet suspends development, doubles lifespan of wormsStrict diet suspends development, doubles lifespan of worms

Identified for the first time what kind of explosive has been used after the detonationIdentified for the first time what kind of explosive has been used after the detonation

Copied from nature: Detecting software errors via genetic algorithmsCopied from nature: Detecting software errors via genetic algorithms

Early Earth may have been prone to deep freezes (12/13/2011)

Tags:
climate

Two University of Colorado Boulder researchers who have adapted a three-dimensional, general circulation model of Earth's climate to a time some 2.8 billion years ago when the sun was significantly fainter than present think the planet may have been more prone to catastrophic glaciation than previously believed.

The new 3-D model of the Archean Eon on Earth that lasted from about 3.8 billion years to 2.5 billion years ago, incorporates interactions between the atmosphere, ocean, land, ice and hydrological cycles, said CU-Boulder doctoral student Eric Wolf of the atmospheric and oceanic sciences department. Wolf has been using the new climate model -- which is based on the Community Earth System Model maintained by the National Center for Atmospheric Research in Boulder -- in part to solve the "faint young sun paradox" that occurred several billion years ago when the sun's output was only 70 to 80 percent of that today but when geologic evidence shows the climate was as warm or warmer than now.

In the past, scientists have used several types of one-dimensional climate models -- none of which included clouds or dynamic sea ice -- in an attempt to understand the conditions on early Earth that kept it warm and hospitable for primitive life forms. But the 1-D model most commonly used by scientists fixes Earth's sea ice extent at one specific level through time despite periodic temperature fluctuations on the planet, said Wolf.

"The inclusion of dynamic sea ice makes it harder to keep the early Earth warm in our 3-D model," Wolf said. "Stable, global mean temperatures below 55 degrees Fahrenheit are not possible, as the system will slowly succumb to expanding sea ice and cooling temperatures. As sea ice expands, the planet surface becomes highly reflective and less solar energy is absorbed, temperatures cool, and sea ice continues to expand."

Wolf and CU-Boulder Professor Brian Toon are continuing to search for the heating mechanism that apparently kept Earth warm and habitable back then, as evidenced by liquid oceans and primordial life forms. While their calculations show an atmosphere containing 6 percent carbon dioxide could have done the trick by keeping the mean temperatures at 57 degrees F, geological evidence from ancient soils on early Earth indicate such high concentrations of CO2 were not present at the time.

The CU-Boulder researchers are now looking at cloud composition and formation, the hydrological cycle, movements of continental masses over time and heat transport through Earth's system as other possible modes of keeping early Earth warm enough for liquid water to exist. Wolf gave a presentation on the subject at the annual American Geophysical Union meeting held Dec. 5-9 in San Francisco.

Toon said 1-D models essentially balance the amount of sunshine reaching the atmosphere, clouds, and Earth's terrestrial and aquatic surfaces with the amount of "earthshine" being emitted back into the atmosphere, clouds, and space, primarily in the infrared portion of the electromagnetic spectrum. "The advantage of a 3-D model is that the transport of energy across the planet and changes in all the components of the climate system can be considered in addition to the basic planetary energy balance."

In the new 3-D model, preventing a planet-wide glaciation requires about three times more CO2 than predicted by the 1-D models, said Wolf. For all warm climate scenarios generated by the 3-D model, Earth's mean temperature about 2.8 billion years ago was 5 to 10 degrees F warmer than the 1-D model, given the same abundance of greenhouse gases. "Nonetheless, the 3-D model indicates a roughly 55 degrees F mean temperature was still low enough to trigger a slide by early Earth into a runaway glacial event, causing what some scientists call a 'Snowball Earth,'" said Wolf.

"The ultimate point of this study is to determine what Earth was like around the time that life arose and during the first half of the planet's history," said Toon. "It would have been shrouded by a reddish haze that would have been difficult to see through, and the ocean probably was a greenish color caused by dissolved iron in the oceans. It wasn't a blue planet by any means." By the end of the Archean Eon some 2.5 billion year ago, oxygen levels rose quickly, creating an explosion of new life on the planet, he said.

Testing the new 3-D model has required huge amounts of supercomputer computation time, said Toon, who also is affiliated with CU-Boulder's Laboratory for Atmospheric and Space Physics. A single calculation for the study run on CU-Boulder's powerful new Janus supercomputer can take up to three months.

Note: This story has been adapted from a news release issued by the University of Colorado at Boulder

Post Comments:

Search

New Articles
Yellowstone supereruption would send ash across North AmericaYellowstone supereruption would send ash across North America

Composition of Earth's mantle revisited

Pacific plate shrinking as it coolsPacific plate shrinking as it cools

Severe drought is causing the western US to rise

Has the puzzle of rapid climate change in the last ice age been solved?Has the puzzle of rapid climate change in the last ice age been solved?

Induced quakes rattle less than tectonic quakes, except near epicenter

Gorges are eradicated by downstream sweep erosion

Foreshock series controls earthquake rupture

Study of Chilean quake shows potential for future earthquake

A new look at what's in 'fracking' fluids raises red flagsA new look at what's in 'fracking' fluids raises red flags

New tools reveal mysteries of an ancient Arctic terraneNew tools reveal mysteries of an ancient Arctic terrane

Ancient shellfish remains rewrite 10,000-year history of El Nino cyclesAncient shellfish remains rewrite 10,000-year history of El Nino cycles

Sea-level spikes, volcanic risk, volcanos cause drought

Burrowing animals may have been key to stabilizing Earth's oxygenBurrowing animals may have been key to stabilizing Earth's oxygen

Scientists warn time to stop drilling in the darkScientists warn time to stop drilling in the dark



Archives
September 2014
August 2014
July 2014
June 2014
May 2014
April 2014
March 2014
February 2014
January 2014
December 2013
November 2013
October 2013
September 2013
August 2013
July 2013
June 2013
May 2013
April 2013
March 2013
February 2013
January 2013
December 2012
November 2012
October 2012
September 2012
August 2012
July 2012
June 2012
May 2012
April 2012
March 2012
February 2012
January 2012
December 2011
November 2011
October 2011
September 2011
August 2011
July 2011
June 2011
May 2011
April 2011
March 2011
February 2011
January 2011
December 2010
November 2010
October 2010
September 2010
August 2010
July 2010
June 2010
May 2010
April 2010
March 2010
February 2010
January 2010
December 2009
November 2009
October 2009
September 2009
August 2009
July 2009
June 2009
May 2009
April 2009
March 2009
February 2009
January 2009
December 2008
November 2008
October 2008
September 2008
August 2008
July 2008
June 2008
May 2008
April 2008
March 2008
February 2008
January 2008
December 2007
November 2007
October 2007
September 2007
August 2007
July 2007
June 2007


Science Friends
Agricultural Science
Astronomy News
Biology News
Biomimicry Science
Cognitive Research
Chemistry News
Tissue Engineering
Cancer Research
Cybernetics Research
Electonics Research
Forensics Report
Fossil News
Genetic Archaeology
Genetics News
Microbiology Research
Nanotech News
Parenting News
Physics News


  Archives |  Submit News |  Advertise With Us |  Contact Us |  Links
Use of this site constitutes acceptance of our Terms of Service and Privacy Policy. All contents © 2000 - 2015 Web Doodle, LLC. All rights reserved.