A few weeks ago (here, or there, among many others) I discussed shortly the increase of the frequency of natural catastrophes. An example is perhaps Australia, with major droughts over the past 10 years; a summer heat wave in Victoria, Australia, caused the massive bushfire in 2009; the flooding in Queensland this winter, as well as a huge cyclone. So it looks like Australia is experiencing that increase of the frequency of natural catastrophes.
Nature published last week a series of interesting papers on natural catastrophes (and its relation with a human factor). Increased flood risk linked to global warming by Quirin Schiermeier (likelihood of extreme rainfall may have been doubled by rising greenhouse-gas levels);Climate change: Human influence on rainfall by Richard P. Allan including some Letter by Min and another Letter by Pall; Human contribution to more-intense precipitation extremes by Seung-Ki Min,et al; and Anthropogenic greenhouse gas contribution to flood risk in England and Wales in autumn 2000 by Pardeep Pall et al.