We are all familiar with them. The ‘skeptics’ that discount all scientific evidence of the dire situation humanity has created with regards to the build-up of green-house gases and the resulting effect on the climate.

Skeptics’ disputes with the IPCC and advocates of action on climate change are commonly along one or more of the following lines:

    * There is no conclusive evidence that climate change is happening;
    * The changes in measured temperatures are part of the natural cycle;
    * Even if the changes are human induced, the scale is not sufficiently large to make changes beyond sensible “least cost” measures; and
    * The economic impact of making substantial cuts in greenhouse gas emissions on the scale suggested by the IPCC or other groups is too large.

While some skeptics challenge a particular technical point or approach in the IPCC reports – for instance, that there is global warming but it is not due to human activity – others have a more sweeping rejection of climate change science and proposed responses in general.

Denial in the face of what we all can observe around us. The horrific bushfires in Australia – oh, just part of the natural cycle. Hardly any news outlet has reported on the connection between climate change and more frequent, and intense bushfires.:

Professor Field says that a warming planet will dry out forests in tropical areas, making them much more likely to suffer from bushfires.

And what about the ‘little’ things around us? This report was released only a few days ago; A Briefing for Policymakers and Concerned Citizens on Audubon’s Analyses of North American Bird Movements in the Face of Global Warming–February, 2009 (warning: pdf). And what did they find?
Analysis of four decades of Christmas Bird Count observations reveal that birds seen in North America during the first weeks of winter have moved dramatically northward–toward colder latitudes–over the past four decades. Significant northward movement occurred among 58% of the observed species–177 of 305. More than 60 moved in excess of 100 miles north, while the average distance moved by all studied species–including those that did not reflect the trend–was 35 miles northward.
There was also movement inland, from warmer coastal states into areas not long accustomed to winter temperatures suitable for their new arrivals.
The analysis found these trends among nearly every type of species, their sheer numbers and variety pointing to a powerful common force contributing to the movements.

So, the canaries are moving north…..

And now, just over a year after the release of the IPCC’s report (the work resulted in the Nobel Peace Prize for 2007) – what is the latest update:

CHICAGO, Feb. 14 — The pace of global warming is likely to be much faster than recent predictions, because industrial greenhouse gas emissions have increased more quickly than expected and higher temperatures are triggering self-reinforcing feedback mechanisms in global ecosystems, scientists said Saturday.

“We are basically looking now at a future climate that’s beyond anything we’ve considered seriously in climate model simulations,” Christopher Field, founding director of the Carnegie Institution’s Department of Global Ecology at Stanford University, said at the annual meeting of the American Association for the Advancement of Science.

Field, a member of the United Nations’ Intergovernmental Panel on Climate Change, said emissions from burning fossil fuels since 2000 have largely outpaced the estimates used in the U.N. panel’s 2007 reports. The higher emissions are largely the result of the increased burning of coal in developing countries, he said.

Reassured now? Still skeptical?

I am sure all of us have anecdotal evidence of changes, but cumulatively it becomes an important data set. In the town where I grew up, the snow now comes an average of 2-3 weeks later than in the ’60s – and spring is also 2-3 weeks earlier. Much less snow accumulates during a typical winter. There are still yearly fluctuations, but the trend is very obvious.

What are your experiences?