Mark up one for global warming

Warmer world gets wetter �-�Satellite observations suggest climate models are wrong on rainfall.

From the above article:

Global warming will increase worldwide precipitation by three times the amount predicted by current climate models, according to a study based on two decades' worth of satellite observations.

The discrepancy between the models and the data might mean that the models are wrong. Or it might be that two decades is not long enough to test their predictions. But researchers believe that the work is a step towards understanding the thorny issue of how global temperatures affect rainfall.

Warmer air holds more water. Satellite observations and climate models agree that each rise of 1 °C in global temperatures increases the amount of water vapour in the atmosphere by about 6.5%.

But climate models project that global warming will also bring weaker winds, leading to less water evaporating from the ocean and counteracting the effect of warming. Models predict that worldwide precipitation — which must match the amount of evaporation — will increase by only 1-3% for each degree of future global warming.

The CSIRO predicts more drought for Australia as a result of global warming, but according to these researchers:

It is currently impossible to predict where additional precipitation will fall, says Wentz. Wet areas may get wetter, but drought-plagued regions might also get some relief.

While I am not a global warming sceptic, my hunch has long been that the CSIRO climatologists are over-confident of their models, and also appear to be amongst the most pessimistic in this field.

Any suggestion that Brisbane might get more rain as a result of global warming is very welcome at the moment.