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<br />Comments to SWSI, November 3, 2003, by John Wiener
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<br />broadly to changing conditions in agriculture - of which changing climate is only one
<br />factor." (Reilly et al. 2001: 122).
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<br />The most important implication, in my opinion, is that the unforeseeable future adds weight to the
<br />wisdom of maintaining water distribution flexibility. The sector team identified changes in sowing
<br />dates, fallowing practices, and changes in irrigation and drainage as likely to be useful in some of
<br />the possible circumstances, and they also were concerned with soil erosion reduction and
<br />impacts of changes in land use. This report is Reilly, J., et al. 2001, Aariculture: the potential
<br />consequences of climate variabilitv and chanqe for the United States, US National Assessment of
<br />the Potential Consequences of Climate Variability and Change, US Global Change Research
<br />Program. It is available at: <http://www.usgcrp.gov/usgcrp/nacc/default.htm>.
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<br />There is also some up-dating from many of the same researchers: Reilly, J., et al., 2003, U.S.
<br />Agriculture and Climate Change: New Results, Climatic Chanae 57: 43-69 (may be available on-
<br />line th rough un iversities: http://www.kluweronline.com/issn/0165-0009/contents ).
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<br />Again, they find with further work that climate impacts on US agriculture as a whole may be small,
<br />in terms of production, and may be less decisive than the influence of other factors.
<br />Economically, farmers and ranchers are not expected to benefit, and some areas may suffer
<br />considerably more than others, while some benefit. Personally, I find this depressing for the
<br />Colorado prospects, and hope that Dr. Pielke Sr. is right about the chances to modify larger-scale
<br />processes by local and regional land and water use.
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<br />One persistent issue in the efforts to consider pOSSible changes is the countervailing influences of
<br />increased precipitation, widely expected, though not everywhere, and increased productivity for
<br />some kinds of crops from the increased levels of carbon dioxide, versus the decreased water
<br />availability from warmer temperatures - the ET increase. The warmer night-time and longer
<br />warm seasons expected are very worrisome for soil moisture, in terms of infiltration and retention.
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<br />Drought and the past variability
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<br />Turning to drought, the 2002 events brought to light a great deal of paleo-climatology on tree-ring,
<br />lake sediment, and other evidence of past dry periods and variability in climate. Since John Henz
<br />addressed this already, I will not. And, the Colorado State University Water Resources Research
<br />Center and other water-related departments and services have provided excellent coverage of
<br />both drought impacts and drought history in the State. It is interesting and sad to read the report
<br />of the 1977 COlorado Drouaht Workshops, available from CSU WRRI, Information Series No. 27,
<br />under publications < http://www.cwrrLcolostate.edui>; things have not changed much. The CSU
<br />WRRI publication on Water in the Balance (#9), A Historv of Drouaht in Colorado:
<br />Lessons Learned and What Lies Ahead is very informative. The drought literature is quite large;
<br />Wilhite and his National Drought Mitigation Center provide excellent sources and syntheses.
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<br />But, from my own work (notably a forthcoming book chapter, soon to be available I hope) on
<br />drought policy, I will note that Homer Kraenzel's powerful advice to "be resilient!" from The Great
<br />Plains in Transition (1955, Oklahoma) hasn't been taken well enough and is still right. The great
<br />majority of drought policy, as Wilhite has shown (noted above) is devoted to emergency
<br />response. I call this "the stability bias" - the urge to "make it like it was", to "get back to normal".
<br />The bias is in investing and re-investing in "normal" when in fact this part of the world has a highly
<br />variable past and doubtless future. Why not invest in resilience - the quality of being able to
<br />absorb shocks without breaking, and being able to - in practical terms - put aside some activities
<br />and enterprises under adverse circumstances, and resume when conditions are more favorable.
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<br />I think it is well worth considering the costs and benefits of a State program, for instance, to
<br />support work by the Extension and Experiment Station and cooperators on designation and
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