One for Tim Blair

Total destruction of forests predicted to cool Earth - Modelling study no excuse for deforestation, researchers warn.

I think I have read something like this before, but news@nature is running this story:

Large-scale deforestation — long fingered as a contributing factor in climate change — could cool Earth, say the researchers behind one of the first attempts to model the phenomenon at a global scale.

Logging is often attacked because living trees help to mop up carbon dioxide, thereby buffering rises in greenhouse gases. But deforestation has different effects in different parts of the world.

In high latitudes, for example, removing the forests could help to cool these regions. This is because the trees, which absorb sunlight, would be replaced by snow-covered fields in winter that reflect the light. But in tropical regions, cutting back on forests would mean that less water is transferred from soils into the atmosphere, meaning fewer clouds and a warmer planet.

Ken Caldeira of the Carnegie Institution of Washington in Stanford, California, and his colleagues have now compared these two effects and declared that the effect of boreal deforestation dominates. Removing all the forests would put a slight brake on global warming, they predict — enough to leave the world 0.3 °C cooler in 2100, they report..

Woodchipping for global warming - that should be Labor's new forestry policy.