Thursday, January 25, 2007

Climate change & climatic extremes: forecasts

One prediction is that with global heating (James Lovelock’s term that emphasizes that humans are cooking the planet) we will be hotter and there will be more climatic disasters. More droughts, floods, cyclones, extremely hot days and so on.

Australia’s climate is dominated by El Nino, and hence those ‘droughts and flooding rains’ that Dorothy Mackellar wrote about are already an integral part of our climate. Hence I thought we might really cope it in terms of increased climatic extremes when things get globally hotter. I also believed that Australia would cop it bad simply through above-average, average temperature elevation effects.

According to recent forecasts provided in the current New Scientist Australia is likely to get 6-7o C hotter – indeed the whole globe gets hotter - but the climatic extremes experienced and the extent of warming will be more moderate than those experienced in many other parts of the world. An exception is the area around Perth which will have a more extreme climate – Perth already faces a looming water supply crisis and is destined to be a climate change 'hotspot' (see R. Hensen, The Rough Guide to Climate Change. Roughguides 2006). Maybe that will finally deflate the booming Perth property market.

Globally the areas that are really hammered in terms of extreme climatic variability are the Amazon rainforest, the Congo Basin and a fair bit of China. These areas are also hammered in terms of the sheer extent of temperature gain - temperature increases will range up to 11 degrees C. The result for China is of particular interest since, although its per capita energy consumptions are low, it already emits 15% of the world's Greenhouse gas emissions. It has a stake in cutting carbon emissions to secure its own future viability!

Michele Battig provides a nice visual graphic of where things get much hotter here. She published her co-authored research in Geophysical Research Letters.

No comments: