Molnar, P. and Ramirez, J.A. 2001. Recent trends in precipitation and streamflow in the Rio Puerco Basin. Journal of Climate 14: 2317-2328.
What was done
The authors conducted a detailed watershed-based analysis of precipitation and streamflow trends for the period 1948-97 in a semiarid region of the southwestern United States, namely, the Rio Puerco Basin of New Mexico.
What was learned
In the words of the authors, "at the annual timescale, a statistically significant increasing trend in precipitation in the basin was detected." This trend was driven primarily by an increase in the number of rainy days in the moderate rainfall intensity range, with essentially no change at the high-intensity end of the spectrum. In the case of streamflow, there was no trend at the annual timescale; but monthly totals increased in low-flow months and decreased in high-flow months.
What it means
Increasing precipitation in a semiarid region sounds like a plus to us. Having most of the increase in the moderate rainfall intensity range also sounds like a plus. Increasing streamflow in normally low-flow months sounds good as well, as does decreasing streamflow in high-flow months. In fact, what more could one possibly want in terms of changes in precipitation? ... especially in a world that (according to the anti-CO2 forces of the planet) is supposed to be experiencing more extreme weather events and increases in floods and droughts?
We once thought that by predicting both more floods and more droughts at one and the same time in response to global warming the climate alarmists were making sure they could not possibly miss in their predictions of CO2-induced calamities. Seems we were wrong.
Reviewed 23 January 2002