Reference
Smith, L.C., Pavelsky, T.M., MacDonald, G.M., Shiklomanov, A.I. and Lammers, R.B. 2007. Rising minimum daily flows in northern Eurasian rivers: A growing influence of groundwater in the high-latitude hydrologic cycle. Journal of Geophysical Research 112: 10.1029/2006JG000327.
What was done
The authors present "a first analysis of a new data set of daily discharge records from 138 small to medium-sized unregulated rivers in northern Eurasia," focusing on providing "a first continental-scale assessment of low-flow trends since the 1930s."
What was learned
Smith et al. report that "a clear result of this analysis is that, on balance, the monthly minimum values of daily discharge, or 'low flows,' have risen in northern Eurasia during the 20th century," adding that "from 12 unusually complete records from 1935-2002 we see that the minimum flow increases are greatest since ~1985." In addition, they write that "discharge reconstructions (up to 1990) modeled from dendrochronology suggest that the late 20th century Eurasian discharge increase, while large, is not unprecedented over the past ~200 years."
What it means
Climate alarmists typically contend that global warming will result in more frequent and more severe floods and droughts throughout the world. From the things discovered by Smith et al., however, it is clear that over much of northern Eurasia, predictions of more drought seem rather off the mark, as daily low flows of the majority of northern Eurasian rivers have been increasing. Moreover, in the words of the five researchers, they have been increasing "in summer as well as winter and in non-permafrost as well as permafrost terrain," with the greatest increases occurring "since ~1985," when the world experienced what climate alarmists typically describe as a warming that was unprecedented over the past one to two millennia.
Consequently, not only did one of the climate alarmists' major negative scenarios fail to materialize, just the opposite actually occurred, as whatever drought tendencies may have originally been present in northern Eurasia were likely significantly ameliorated between 1985 and the present.
Reviewed 15 October 2008