Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Modern day scourge helped ancient Earth escape a deathly deep freeze

The planet’s present day greenhouse scourge, carbon dioxide, may have played a vital role in helping ancient Earth to escape from complete glaciation, say scientists in a paper published online today.

In their review for Nature Geoscience, UK scientists claim that the Earth never froze over completely during the Cryogenian Period, about 840 to 635 million years ago.

This is contrary to the Snowball Earth hypothesis, which envisages a fully frozen Earth that was locked in ice for many millions of years as a result of a runaway chain reaction that caused the planet to cool.

What enabled the Earth to escape from a complete freeze is not certain, but the UK scientists in their review point to recent research carried out at the University of Toronto. This speculates that the advancing ice was stalled by the interaction of the physical climate system and the carbon cycle of the ocean, with carbon dioxide playing a key role in insulating the planet.

The Toronto scientists say that as Earth’s temperatures cooled, oxygen was drawn into the ocean, where it oxidized organic matter, releasing the greenhouse gas carbon dioxide into the atmosphere.

The review’s lead author, Professor Phillip Allen, from Imperial College London’s Department of Earth Science and Engineering, says that something must have kept the planet’s equatorial oceans from freezing over. He adds:

“In the climate change game, carbon dioxide can be both saint and sinner. These days we are so concerned about global warming and the harm that carbon dioxide is doing to our planet. However, approximately 600 million years ago, this greenhouse gas probably saved ancient Earth and its basic life forms from an icy extinction.”

Professor Allen, whose previous research has found evidence demonstrating hot and cold cycles in the Cryogenian period, says a plethora of papers has been published and much debate has been devoted to the Snowball Earth theory since it was originally proposed. He says:

“Sedimentary rocks deposited during these cold intervals indicate that dynamic glaciers and ice streams continued to deliver large amounts of sediment to open oceans. This evidence contradicts the Snowball Earth theory, which suggests the oceans were frozen over. Yet, many scientists still believe Snowball Earth to be correct.”

Professor Allen hopes his review in Nature will prompt climate modellers to realign their thinking about the Cryogenian period and review their models to reflect a warmer Earth during this time. He adds:

“There is so much about Earth’s ancient past that we don’t know enough about. So it is really important that climate modellers get their targets right. They need to build into their calculations a warmer planet, with open oceans, despite lower levels of solar radiation at this time. Otherwise, climate models about the Earth’s distant past are aiming for a target that never existed.”

Colin Smith | alfa
Further information:

More articles from Earth Sciences:

nachricht UCI and NASA document accelerated glacier melting in West Antarctica
26.10.2016 | University of California - Irvine

nachricht Ice shelf vibrations cause unusual waves in Antarctic atmosphere
25.10.2016 | American Geophysical Union

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

How nanoscience will improve our health and lives in the coming years

27.10.2016 | Materials Sciences

OU-led team discovers rare, newborn tri-star system using ALMA

27.10.2016 | Physics and Astronomy

'Neighbor maps' reveal the genome's 3-D shape

27.10.2016 | Life Sciences

More VideoLinks >>>