Tuesday, October 5, 2010

How much should crop production decline during a drought?

According to the report I recently published with UC-Davis researchers, crop production in the San Joaquin Valley declined between 2.3% and 2.5% in the 3rd year of a extended drought in which water supplies declined by a much greater percentage.  I find the 2.5% decline to be a remarkably low number, half what most experts predicted, and the agriculture industry and water managers certainly deserve credit for their achievement in the face of adversity. 

Still, the conventional wisdom is that we have a terribly broken water system, especially for agriculture.  Would a truly broken and disfunctional system deliver such results?  To those who hold this view, I wonder how much would crop production have to decline in a drought for them to be satisfied with the water system.  Would -1% be good enough?  0%?

When the drought is over, agricultural production in the Valley will still be constrained by environmental pumping restrictions brought on by a collapse in fish populations.  The highest estimate I have seen of the impact of these pumping restrictions on Valley crop production is a 1% decline.  Is that too much to ask given the great environmental damage created by the pumps?  What is a reasonable expectation?  -0.3%?  0%?

Postscript (10/6):  I see that asking reasonable questions like this about Valley agriculture has been called waterboarding and generates comparisons to Nazi's these days.

1 comment:

  1. Dry years are often very productive, since pollination conditions tend to be good, and weeds and diseases are suppressed. Of course, that assumes one has some water; but few farmers had *no* water that year. Many did get by using old salty wells, which is clearly an unsustainable strategy.
    So the observation that the system is broken still holds. Nunes' hysterical and insulting comment was unhelpful, and ought to have been revealing to some of his supporters.