Archives for January 25, 2008

This dominant 4.5metre male Estuarine Crocodile (Crocodylus porosus) resides a kilometre or so downstream from my own abode on Cooper Creek; a proximity that we never forget!

It has long been known that crocodile gender is determined by temperature. If the temperature of egg incubation is cool, around 30 degrees C, the hatchlings are all female. Warmer temperatures, around 34 degrees C, hatch all males. There is also strong population bias towards females; often as high as 10 to 1.

For about thirty years, this skewed ratio was thought to provide an evolutionary advantage, whereby sex ratio optimises survivorship considerations.

In a recent News in Science article by Dani Cooper, entitled ‘Sex-change lizards settle a hot topic’, Professor Rick Shine of Sydney University and his former student Dr Daniel Warner, now of Iowa State University, report that they have proven this 30-year-old theory.

Studying the relatively short-lived Jacky dragon (Amphibolurus muricatus), which produces off-spring within one year of hatching and lives no longer than four years, the researchers found that hormonal manipulation of gender determination had no effect on the health and survival of the hatchlings, but the natural males were five to 10 times better in terms of mating and producing offspring, while the natural females produced four to five times more offspring.

It was therefore shown that the incubation temperature that produces that sex in nature optimised reproductive success of each sex.

Speaking in Davos, at the World Economic Forum, Al Gore is quoted saying, ‘Climate change ‘significantly worse’ than feared.’

Gore claims, “the climate crisis is significantly worse and unfolding more rapidly than those on the pessimistic side of the IPCC projections had warned us.” Apparently there are new forecasts that the North Pole ice caps “could” disappear during summer within 5 years. We can hold you to that one Al.

Mmmm! Since 1990, the IPCC has lowered both it’s temperature and sea level rise forecasts, in 1995, 2001 and 2007. In fact, the IPCC seems to have abandoned decadal sea level forecasts in AR4 and gone for an unverifiable 90-year projection/prediction.

If any readers know where Al gets his worsening ‘climate crisis’ information from, let us know.

The American Geophysical Union (AGU) have released this statement on Climate Change:

The Earth’s climate is now clearly out of balance and is warming. Many components of the climate system – including the temperatures of the atmosphere, land and ocean, the extent of sea ice and mountain glaciers, the sea level, the distribution of precipitation, and the length of seasons – are now changing at rates and in patterns that are not natural and are best explained by the increased atmospheric abundances of greenhouse gases and aerosols generated by human activity during the 20th century. Global average surface temperatures increased on average by about 0.6°C over the period 1956-2006. As of 2006, eleven of the previous twelve years were warmer than any others since 1850. The observed rapid retreat of Arctic sea ice is expected to continue and lead to the disappearance of summertime ice within this century. Evidence from most oceans and all continents except Antarctica shows warming attributable to human activities. Recent changes in many physical and biological systems are linked with this regional climate change. A sustained research effort, involving many AGU members and summarized in the 2007 assessments of the Intergovernmental Panel on Climate Change, continues to improve our scientific understanding of the climate.

During recent millennia of relatively stable climate, civilization became established and populations have grown rapidly. In the next 50 years, even the lower limit of impending climate change – an additional global mean warming of 1°C above the last decade – is far beyond the range of climate variability experienced during the past thousand years and poses global problems in planning for and adapting to it. Warming greater than 2°C above 19th century levels is projected to be disruptive, reducing global agricultural productivity, causing widespread loss of biodiversity, and-if sustained over centuries-melting much of the Greenland ice sheet with ensuing rise in sea level of several meters. If this 2°C warming is to be avoided, then our net annual emissions of CO2 must be reduced by more than 50 percent within this century. With such projections, there are many sources of scientific uncertainty, but none are known that could make the impact of climate change inconsequential. Given the uncertainty in climate projections, there can be surprises that may cause more dramatic disruptions than anticipated from the most probable model projections.

With climate change, as with ozone depletion, the human footprint on Earth is apparent. The cause of disruptive climate change, unlike ozone depletion, is tied to energy use and runs through modern society. Solutions will necessarily involve all aspects of society. Mitigation strategies and adaptation responses will call for collaborations across science, technology, industry, and government. Members of the AGU, as part of the scientific community, collectively have special responsibilities: to pursue research needed to understand it; to educate the public on the causes, risks, and hazards; and to communicate clearly and objectively with those who can implement policies to shape future climate.

Human Impacts on ClimateAdopted by Council December 2003
Revised and Reaffirmed December 2007

Marc Morano’s response:

“The AGU Board issued a statement on climate change without putting it to a vote of the group’s more than 50,000 members. Its sweeping claims, drafted by nine committee members, rely heavily on long term computer model projections, cherry-picking of data and a one-sided view of recent research. As with the recent statements by the AMS and the NAS, this is the product of a small circle of scientists who all share the same point of view, and who failed to put their statement to a vote of the AGU members on whose behalf they now claim to speak. As such it amounts to nothing more than a restatement of the opinion of a small group, rather than a consensus document.”

Marc Morano
Communications Director
Senate Environment and Public Works Committee (EPW) Inhofe Staff