Frozen in Time
Oct 09, 2007
Younger Dryas Glaciation Northern Hemisphere Only?

Science Alert, 8 October 2007

If the Earth is heading for a new ice age, Australia may not be as affected as countries in the Northern Hemisphere, according to new research from The Australian National University published in Science.  Dr Timothy Barrows, a palaeoclimatologist at the ANU Research School of Physical Sciences and Engineering, says that a freak cooling at the end of the last ice age 12,900 years ago, was a phenomenon felt only in the north, not globally as previously thought.

This rapid cooling, which brought on an ice age for 1400 years, is known as the Younger Dryas event. It was caused by a disruption of ocean circulation in the Atlantic Ocean, which could occur again if the Greenland Ice Sheet were to melt.

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“It was thought that climate change was always global, but our research shows that is not necessarily the case, in fact what happens in the north can be the opposite of what happens in the south. So if the Greenland Ice Sheet does melt because of global warming, triggering another ice age, Australia and New Zealand are the places to be,” Dr Barrows said. Read more here.

Oct 06, 2007
Prominent BBC Naturalist Joins Skeptics: ‘Our Climate Has Always Changed’

By Michael Deacon, UK Telegraph

One subject gets Titchmarsh more worked up than accusations of blandness, though. Perhaps, coming from a man who loves nature, it’s a slightly surprising one: our obsession with global warming.

‘I wish we could grow up about it,’ he says. ‘I’m sure we are contributing to global warming, and we must do all we can to reduce that, but our climate has always changed. The Romans had vineyards in Yorkshire. We’re all on this bandwagon of ‘Ban the 4x4 in Fulham’. Why didn’t we have global warming during the Industrial Revolution? In those days you couldn’t have seen across the street for all the carbon emissions and the crap coming out of the chimneys.’ He pauses for breath, then smiles. ‘Sorry, bit of a tirade there.’

Surely he worries that global warming may threaten some of the species in his series. But this doesn’t seem to bother him too much. ‘We’ll lose some, we’ll gain others,’ he says. ‘Wildlife is remarkably tenacious. Nature always copes.’

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Alan Titchmarsh, UK Naturalist

Oct 03, 2007
Scientific Consensus on Man-Made Ozone Hole May Be Coming Apart

Nature

As the world marks 20 years since the introduction of the Montreal Protocol to protect the ozone layer, Nature has learned of experimental data that threaten to shatter established theories of ozone chemistry. If the data are right, scientists will have to rethink their understanding of how ozone holes are formed and how that relates to climate change.

Markus Rex, an atmosphere scientist at the Alfred Wegener Institute of Polar and Marine Research in Potsdam, Germany, did a double-take when he saw new data for the break-down rate of a crucial molecule, dichlorine peroxide (Cl2O2). The rate of photolysis (light-activated splitting) of this molecule reported by chemists at NASA’s Jet Propulsion Laboratory in Pasadena, California1, was extremely low in the wavelengths available in the stratosphere - almost an order of magnitude lower than the currently accepted rate.

“This must have far-reaching consequences,” Rex says. “If the measurements are correct we can basically no longer say we understand how ozone holes come into being.” What effect the results have on projections of the speed or extent of ozone depletion remains unclear.

Other groups have yet to confirm the new photolysis rate, but the conundrum is already causing much debate and uncertainty in the ozone research community. “Our understanding of chloride chemistry has really been blown apart,” says John Crowley, an ozone researcher at the Max Planck Institute of Chemistry in Mainz, Germany.

“Until recently everything looked like it fitted nicely,” agrees Neil Harris, an atmosphere scientist who heads the European Ozone Research Coordinating Unit at the University of Cambridge, UK. “Now suddenly it’s like a plank has been pulled out of a bridge.” Post is here.

Oct 03, 2007
A Challenge to the Carbon Dioxide / Global Warming Connection

By Jules Kalbfeld

One issue that seems to have been lost or avoided in the debate over the connection between atmospheric carbon dioxide (CO2) and global warming is the miniscule mass of CO2 that is being blamed for so many past, present and predicted natural disasters. The mass of atmospheric CO2 is extremely small when compared to the total mass of the Earth’s atmosphere and even smaller when compared to the combined masses of the land and water features on the Earth’s surface as well.

The directly proportional relationship that exists between the mass of any object and its heat capacity is essentially axiomatic: all other factors being the same, the larger the mass of an object, the greater its ability to capture, store, transport and release heat. Since the concentration of CO2 in the Earth’s atmosphere is so small, the notion that it is causing global warming seems to ignore this basic truth.

This discussion illustrates how the connection between global warming and the tiny mass of CO2 in the Earth’s atmosphere has been exaggerated. The challenge, expressed here, simply asks the proponents of CO2 induced global warming to reconcile their theories with classical scientific principles and established physical data.
See paper here.

Sep 24, 2007
Dr. William Gray’s Response to Trenberth’s Op Ed “Clarity Emerging on Hurricanes?”

By Dr. William Gray

The September 14, 2007 Op Ed piece “Clarity Emerging on Hurricanes” by Kevin Trenberth may have been timed to coincide with the congressional Senate hearing on hurricanes and climate change scheduled in the Dirksen Building on 19 Sept ‘07.

Trenberth’s central theme of emerging clarity on hurricane and climate change is, in my view, totally bogus as was his Scientific American article of July 2007 saying how hurricanes will change in the future.  This article was very one sided and factually wrong in many places.  It appears not to have been peer reviewed. 

There is absolutely no clarity emerging on the question of human influence on hurricanes and hurricane changes associated with climate change.  This dichotomy between the group of researchers saying that humans are likely influencing hurricanes (Trenberth is of this group) and the many others of us saying there is no solid evidence or physical basis for such a linkage is widening, not converging.  Most of those believing that humans are affecting hurricanes have a vested interest that their views be accepted.  Most of us skeptics do not.

The papers Trenberth cites in his Op Ed as backing a growing clarity on this topic have major flaws and are likely not accepted by most of us who are skeptical of significant human influences on hurricanes.  There is no reliable evidence that Atlantic basin (or global) hurricane activity shows changes over the last century beyond the changes brought about by the oscillating Atlantic Ocean thermohaline circulation which appears to be driven by salinity changes.  United States landfalling hurricane numbers (the most reliable long-term data we have) show a small decrease over the last century.  This is particularly noticeable in US landfalling major (Cat 3-4-5) hurricanes.  In the 41 year period between 1925-1965 there were 39 US landfalling major hurricanes.  In the last 41 year period of 1966-2006 when global CO2 amounts were rising there were only 22 such US major hurricane landfalls.  How can anyone honestly conclude that long term Atlantic hurricane activity is increasing?

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