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Last modified
7/28/2009 2:42:09 PM
Creation date
4/30/2008 2:44:24 PM
Metadata
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Template:
Weather Modification
Contract/Permit #
14-06-D-7052
Title
Ecological Impacts of Snowpack Augmentation in the San Juan Mountains, Colorado
Date
3/1/1976
State
CO
Weather Modification - Doc Type
Report
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<br /> Question <br />1.d. To what extent have the following <br /> impacted your project? <br />(1) Technical competence of project <br /> professionals <br />(2) Personal relations among project <br /> professionals <br />(3) Conceptual competence of project <br /> professionals <br />(6) Quality of support personnel <br /> <br />No. of Responses <br /> <br />Table 7. The perceived scientific competence of investigators <br /> <br />Modal Response <br /> <br />No. in Mode <br /> <br />16 <br /> <br />Favorable <br /> <br />8 (14) <br /> <br />16 <br /> <br />Favorable <br /> <br />8 (13) <br /> <br />16 <br />15 <br /> <br />Favorable <br />Adequate <br /> <br />8 (14) <br />6 (8) <br /> <br />Source: Responses to the questionnaire administered to SJEP investigators by Benton & Meiman in mid-1975 <br />(Appendix A). <br /> <br />Questions condensed from the actual form used. <br /> <br />All questions were scored by each respondent on a scale with 7 classes. The modal response is the one used <br />most frequently by respondents. For range of modal classes, see Appendix A. <br /> <br />Values in parentheses are for the modal class and the two adjacent ones. <br /> <br />It is also addressed by the amount of external fund- <br />ing made available for SJEP-related research from <br />agencies other than the Bureau of Reclamation. In <br />addition to these formal contacts, we have attempted <br />to keep in touch with the Colorado Division of <br />Wildlife, and with the U.S. Forest Service personnel <br />in southwestern Colorado, since the research has <br />been conducted on federal land administered by the <br />Forest Service. However, these contacts have been <br />more for the purpose of information exchange than <br />for cooperative research. <br /> <br />RESEARCH STRATEGIES AND TOOLS <br /> <br />Three general approaches to evaluating the impacts of <br />snowpack augmentation were considered at the start <br />of the San Juan Ecology Project in 1970: monitoring <br />by classical comparative designs, process studies, <br />and simulation modeling. These three are not <br />entirely independent and all of them have been used, <br />at least in parts of the project. Nevertheless, <br />the decision was made not to attempt the monitoring <br />of actual effects by classical comparative studies <br />on a project-wide scale. Instead, the SJEP concen- <br />trated on the elucidation of the mechanisms whereby <br />the seeding agent or the winter snowfall could <br />produce ecological responses. Ecosystem simulation <br />modelling would have been barely feasible in 1970 <br />and would have been severely handicapped by the un- <br />even research coverage of the ecosystem components <br />which appeared after the selection of projects for <br />Phase II. <br /> <br />These alternatives and others have been evaluated <br />by Cooper et al. (1974, Section 2) but are worth <br />comment in the light of SJEP experience. They are <br />considered in the sequence introduced above: <br />classical designs; process studies; and ecosystem <br />modelling. This is followed by a discussion of the <br />interpretation and evaluation of research results. <br /> <br />Classical Designs <br /> <br />Under this heading are three broad-scale approaches <br />which require comparisons in either time or space, <br />or both of these. They are (1) before-and-after <br />studies of the same system, (2) target-and-control <br />comparisons, and (3) time trend analyses. <br /> <br />Both the before-and-after and paired catchment <br />(target-and-control) approaches have a long history <br />of use, especially in hydrology, and are often <br />combined because of the need to calibrate a paired <br />comparison. Cons,equently, the statistical procedures <br />needed to evaluate the results gained from such <br />procedures are readily available. In SJEP, these <br />approaches were rejected for four reasons. <br /> <br />1. The before-case was not available; cloud seeding <br />and SJEP started together. <br /> <br />2. The comparability of target-and-control areas <br />could not be high because wide spatial <br />separation would be necessitated by the size <br />of the San Juan target area. This problem would <br />be exacerbated by the lack of a calibration <br />period before the start of cloud seeding. <br /> <br />3. The response time of many of the systems likely <br />to be influenced by snowpack augmentation in <br />the San Juan Mountains was not known but was <br />thought to be longer than the initial 4-year <br />study period. <br /> <br />4. The intrinsic variability of the natural systems <br />under study also was not known in detail, but <br />seemed likely to be much greater than that <br />capable of being produced by cloud seeding. <br /> <br />These four reasons appear among the reasons given <br />by Cooper et al. (1974, p. 21) for not recommending <br />before-and-after or paired comparison studies. <br /> <br />~ <br />I <br /> <br />Also included as a classical design is time trend <br />analysis, i.e. the search for a consistent change <br />in the ecosystem with time from the start of cloud <br />seeding. This general approach was rejected in SJEP <br />for many of the reasons listed above and because <br />other problems were foreseen. Temporal trends are <br />unlikely to be clearly identified by a study of a <br />few years duration, particularly where a system state <br />is described by a single annual value (e.g. plant <br />productivity or wildlife population). This problem <br />is magnified by the natural variability of the system <br />studied and by its long response time. Any attempt <br />to define time trends in the systems studied by SJEP <br />investigators would probably require decades of study, <br /> <br />28 <br />
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