Warming Deep-Sea Temperatures Ended Last Ice Age 

Not by Fire but by Ice


Discover What Killed the Dinosaurs . . . and Why it Could Soon Kill Us

Web www.iceagenow.com

8 October 07


Generate income from 
your website with
Google Adsense

Warming Deep-Sea Temperatures 
Ended Last Ice Age

Study Validates My Theories
27 Sep 07 - USC College researcher shows that deep-sea temperatures rose 1,300 years before the buildup of atmospheric carbon dioxide, ruling out CO2 as driver of the last ice age’s meltdown.

In contrast to what is often inferred from the geologic record, carbon dioxide did not cause the end of the last ice age, a new USC study published in Science suggests.

"There has been this continual reference to the correspondence between CO2 and climate change as reflected in ice core records as justification for the role of CO2 in climate change," said paleoclimatologist Lowell Stott, the study’s lead author and a professor of earth sciences at USC College.

"You can no longer argue that CO2 alone caused the end of the ice ages."

Deep-sea temperatures warmed about 1,300 years before the tropical surface ocean and well before the rise in atmospheric CO2, the study found. The finding suggests the rise in greenhouse gas was likely a result of warming – but not its main cause. 

            (Rising CO2 levels are a result of warming, not a cause 
            - just as I say in "Not by Fire but by Ice.")

"What this means is that a lot of energy went into the ocean long before the rise in atmospheric CO2," Stott said.

But where did this energy come from? Evidence pointed southward.

The warming deep water appeared to come from the Antarctic Ocean, then moved northward, the scientists wrote

In addition, the researchers noted that the increases in deep-sea temperature coincided with the retreat of Antarctic sea ice, both occurring 19,000 years ago, before the northern hemisphere’s ice retreat began.

Finally, Stott and colleagues found a correlation between melting Antarctic sea ice and increased springtime solar radiation over Antarctica, suggesting this was the energy source.

As the sun pumped in heat, the warming accelerated because of sea-ice albedo feedbacks, in which retreating ice exposes more of the ocean that can absorb heat from the sun, much like a dark T-shirt on a hot day, and this results in more melting.

In addition, the authors’ model showed how changed ocean conditions may have been responsible for the release of CO2 from the ocean into the atmosphere, which like the albedo feedbacks, also accelerated the warming. 

            (I also say this in "Not by Fire but by Ice" – that 
            rising CO2 levels come from the warming ocean.)

The link between the sun and ice age cycles is not new. The theory of Milankovitch cycles states that periodic changes in Earth’s orbit cause increased summertime solar radiation in the northern hemisphere, which controls ice size.

If CO2 caused the warming, one would expect surface temperatures to increase before deep-sea temperatures, since the heat slowly would spread from top to bottom. Instead, carbon-dating showed that the water used by the bottom-dwelling organisms began warming about 1,300 years before the water used by surface-dwelling ones, suggesting that the warming spread bottom-up instead.

            (Just as I say in "Not by Fire but by Ice." It’s not 
            global warming, it’s ocean warming. And this time 
            it’s leading us into an ice age.)

Stott is an expert in paleoclimatology and was a reviewer for the Intergovernmental Panel on Climate Change. He also recently co-authored a paper in Geophysical Research Letters tracing a 900-year history of monsoon variability in India.

See entire article by Terah U. DeJong:
Thanks to Vagrant Viking for this link

See also:
Thanks to Jimmy Walter for this link

See also:
Thanks to Craig Adkins for this link



Order Book I Q & A I Book Reviews I Plant Hardiness Zone Maps I Radio Interviews I Table of Contents I Excerpts I Author Photo I Pacemaker of the Ice Ages I Extent of Previous Glaciation I Crane Buried in Antarctic Ice Sheet I Ice Ages and Magnetic Reversals I It's Ocean Warming I E-Mail Robert at rwfelix@juno.com l Expanding Glaciers