Although Howitt thought that their numbers on revenues were of greater interest, it turned out that the numbers on jobs attracted much more attention. The media, politicians and farmers all seized on the higher figure** (naturally) in making their arguments that export cutbacks were resulting in terrible human suffering. This pressure was at least partially responsible for Judge Wanger's decision to take "human impacts" into consideration when enforcing the Endangered Species Act, i.e., to consider larger exports.***
In my opinion, Howitt et al.'s estimate of impacts was ripe for misunderstanding:
- As they mentioned, markets could reduce the impacts.
- Their estimates were confounded with high unemployment in places like Firebaugh and Mendota, where 30-40 percent unemployment is the norm, year after year, high water or low.
- They were the result of a simulation (the impact of water on crops) fed into a simulation (the impact of crops on revenue) fed into a simulation (the impact of revenue on jobs). Read my critique of this method here.
Anyway, what's upset me about this whole business is not the well-meaning debate between two academics, but the way that various partisan groups have used the original 80,000 figure** to rant about "blood on the arid soil" on the one side (Hannity and Stewart on Hannity), or claims of "nothing happening here, please move along" on the other. Although I have been very critical of
(I am really sad that the fight has turned into "pumps on" vs. "pumps off." First, the pumps ARE on. Second, water markets could have reduced the economic and social cost of shortages.)
Right -- so that's some background...
In this revision [PDF] to the revision**** to their original study, Howitt et al. admit to using some flawed data in the first study and estimate 21,000 total job losses, with 16,000 from drought and 5,000 from pumping restrictions.
Although their note is pretty geeky (IMPLAN vs. REMI vs. SWAP simulation methods and detailed comparisons with Michael's estimate of 6,000 lost jobs, of which 2,000 are from pumping restrictions), and I still dislike simulations (the world is too complex), I am happy to see Howitt et al.'s efforts to improve accuracy.
And yet, I have the following gripes:
- They claim that county data are inaccurate because "impacts on the west side of Fresno county might be greater than on the east side." After several emails with Howitt, I do not understand this problem. I do understand that their model resolution is better than county-wide, and that their statistics are more "granular" than county EDD statistics on employment, but the numbers should match (in the medium term). If we want to talk about data problems, we can go on for days!
- It does seem as if Howitt et al. are defending assumptions when calibrating and interpreting their model that contribute to higher job losses. (It's obvious that they have an incentive to do so, since they -- like everyone -- prefer that their new conclusions support their old ones.) Of course, Michael appears to be doing the same, in the opposite direction. He averages his estimated impact of 12,000 losses and a "no impact" lower bound of zero losses to arrive at a final figure of 6,000 losses.
- Partisans will use the numbers that serve their interest, i.e., we will still see the inaccurate and disowned 80,000 figure.**
- 21,000 lost jobs is bad but remember that those are only about one percent of the region's 1.7 million jobs (in a population of 3.8 million).
- Howitt and Michael are at least converging in agreement on the strengths, weaknesses and differences between their methods, even if their results vary.
- I had lunch with Howitt and Michael last week. Both of them were visibly tired of the controversy over these numbers. Although everyone likes some attention to their work, they've been getting perhaps too much -- especially of the negative variety.
- At this lunch, I proposed that I write a short note comparing and contrasting their methods and results (similar to my attempt here). They think that's a good idea (getting everything in one place, side-by-side) -- as long as they don't have to devote too much MORE time to my effort. I will pay attention to the response to this post before I proceed.
* The study used January 2009 data on groundwater pumping and ZERO surface water exports from the Delta.
** Howitt says he has no idea how the 60,000-80,000 figure was inflated to 90,000 lost jobs, but it's sadly obvious why politicians, pundits and partisans would keep using a number he discarded five months ago.
*** Exports were reduced in compliance with the "biological opinion" that they were harming the Delta Smelt, an endangered species.
**** In the earlier revision, Howitt et al. considered updated data on groundwater pumping and the updated estimates of surface water deliveries (from zero to 10-15 percent of contracted allocations) and estimated 35,000 job losses and $980 million in lost revenue; the recent update used better data to estimate 21,000 job losses; economic losses are the same.