Scientists study 'Snowball Earth'

Nov 28, 2006

Canadian scientists have determined the factors involved in ending a severe ice age 750 million years ago that nearly completely froze Earth's oceans.

Since the factors initiating a so-called "Snowball Earth" era have been the subject of much study, Jeffrey Lewis and colleagues at the University of Victoria focused on determining the factors that pulled Earth from its snowball state.

Noting that accepted values for both snow and ice albedo -- the ratio of incident to reflected solar radiation -- cover a wide range, the researchers sought to quantify the relative sensitivity of various surface albedos on the same climate model as it emerges from a snowball state.

They found the range of ice, snow, and land albedos and the resulting minimum carbon dioxide greenhouse forcing required for deglaciation of the Neoproterozoic snowball Earth. They also found greenhouse forcing can vary by nearly an order of magnitude within the accepted albedo ranges, suggesting the physics of deglaciation in terms of radiation budgets, snow and ice dynamics, and atmospheric processes needs to be better modeled.

The study is detailed in the journal Geophysical Research Letters.

Copyright 2006 by United Press International

Explore further: Icelandic volcano sits on massive magma hot spot

add to favorites email to friend print save as pdf

Related Stories

Image: Comet 67P/Churyumov–Gerasimenko

Oct 21, 2014

It was 45 years ago when astronomer Klim Churyumov and Svetlana Gerasimenko, one of his researchers, unwittingly began a new chapter in the history of space exploration.

Study debunks theory on end of 'Snowball Earth' ice age

May 25, 2011

A team of scientists led by researchers from Caltech report in this week's issue of the journal Nature that the rocks on which much of a theory on how the "Snowball Earth" ice age ended was based were formed ...

Clouds could explain how Snowball Earth thawed out

Nov 13, 2012

Glaciation events during the Neoproterozoic (524-to-1,000 million years ago) and Paleoproterozoic (1,600-to-2,500 million years ago) periods - events that spawned ice ages that persisted for millions of years ...

Recommended for you

Icelandic volcano sits on massive magma hot spot

1 hour ago

Spectacular eruptions at Bárðarbunga volcano in central Iceland have been spewing lava continuously since Aug. 31. Massive amounts of erupting lava are connected to the destruction of supercontinents and ...

NASA sees Tropical Storm Ana still vigorous

3 hours ago

NASA's TRMM satellite saw that Tropical Storm Ana was still generating moderate rainfall is it pulled away from Hawaii. The next day, NASA's Aqua satellite saw that wind shear was having an effect on the ...

User comments : 0