Laserfiche WebLink
<br />-,---- <br /> <br />-r- <br /> <br />- <br />.- <br /> <br />P values < alpha)j100 where alpha is the <br />specified significance level. <br />Estimated project duration values <br />suggest that the Moroccan program must <br />operate efficiently at least 6 years with 10% <br />increases for at least a 50% probability-of- <br />detection (alpha = 0.1). However, if the cloud <br />seeding program achieves a 15% increase in <br />seasonal streamflow, at least a 75% probability <br />of detection can be achieved with a 6-year <br />treated period and alpha is set at the more <br />stringent 0.05 level. <br /> <br />5. HYDROLOGIC AND ECONOMIC <br />BENEFIT - COST STUDY <br /> <br />The hydrologic and economic study was <br />designed to evaluate the distribution and use <br />patterns of added streamflow that might be <br />produced by cloud seeding operations in the <br />Oued Oum er Rbia Basin and then provide a <br />benefit - cost analysis of the value of the <br />additional streamflow produced versus the total <br />cost of cloud seeding operations (Cheney and <br />Shuyler, 1987). Cheney and Shuyler used a <br />river simulation model from the Government of <br />Morocco to determine the physical impact of <br />5 and 10% increases in streamflow from 1939 <br />to 1984. The results were combined with <br />economic values of additional water for <br />irrigation, domestic and industrial purposes, <br />and hydroelectric power to determine the <br />benefit to cost ratio for the project. <br />Preliminary analysis indicates a benefit to cost <br />ratio of 1.2 and 2.2 for 5 and 10% increases, <br />respectively. The internal rate of return was <br />estimated at 23 and 70% for 5 and 10% <br />increases, respectively. <br /> <br />6. SUMMARY AND CONCLUSIONS <br /> <br />The Programme AI Ghait - Winter <br />Snowpack Augmentation Demonstration <br />Project in Morocco's High Atlas Mountains has <br />conducted scientific seeding operations using <br />target-control nonrandomized statistical design <br />since 1984. Operational cloud seeding <br />efficiency levels were 10 to 15% during the <br />project's first field season in 1984 and increased <br />to 40 to 70% only after ground generators were <br />installed in January 1987. The efficiency <br />increased to 70 to 80% in 1988 as operators <br />gained experience and communications <br />improved. The preliminary physical analyses of <br />clouds are encouraging and indicate that <br />seed able clouds often occur. At least 6 years <br />of efficient cloud seeding operations producing <br />a 10 to 15% increase in streamflow must be <br />conducted to achieve acceptable probability-of- <br />detection levels. Given that efficient cloud <br /> <br />seeding operations did not begin until February <br />1987 after the ground-based generators were <br />installed, the project should continue <br />opc~rations through the 1992-93 winter season. <br />The preliminary estimates from the <br />hydrologic-economic analyses are e:ncouraging. <br />However, evaluation of actual streamflow <br />observations is needed to properly assess the <br />physical meaning of these economic estimates. <br />USAID assistance on Programme Al <br />Ghait is scheduh:d to end during 1989. A final <br />report from USBR to USAID containing more <br />details on this project should be available by <br />the end of the y(:ar. <br /> <br />REFERENCES <br /> <br />Baddour, 0" and R. Rasmussen, 1988: <br />Microphysical observations over the Atlas Mountains in <br />Morocco. Preprint, 10th International Cloud Physics <br />Conference, WMO, pp. 356-358. <br />Baddour, 0., M, Nbou, M. El Mokhtari, R. M. <br />Rasmussen, D. B. Johnson, and D. A. Matthews, 1989: <br />Seedability of Moroccan Clouds. 5th International <br />Weather Modification and Applied Cloud Physics <br />Cottference, WMO. <br />Benass~ M., 1988: Adaptation of the SCPP <br />targeting model to Morocco. Unpublished; available from: <br />Dirl~ction de la Meteorologie Nationale, DDR-Meteo, <br />Aeroport Casa-Anfa, BP 8106, Casablanca 02, Morocco. <br />Cheney, R. W., and K. D. Shuyler, 1988: Work plall <br />for hydrologic and economic evaluations with ill Programme <br />Al Ghait. Bureau of Reclamation, Denver, CO, 18 pp. <br />El Majdoub, A., J. G. Medina, and H. R. Orville, <br />1989: Adaptation of the Rhea orographic precipitation <br />model to Morocco. 5th International Weather <br />Modification and Applied Cloud Physics Conference, <br />WMO. <br />Hartzell, C., D. Matthews, B. Silverman, <br />S. Benarafa, M, Maidane, A. El Majdoub, Y. LeGoff, <br />1986: Operations plan, Programme Al Gllait. Bureau of <br />Reclamation, Denver, CO, 200 pp. <br />Loukah, El B., 1986: Preliminary Studies of Cloud <br />Seedability over the Atlas Mountains. M.S. Thesis, South <br />Dakota School of Mines and Technology, Rapid City, SD, <br />80 pp. <br />Mielke, P. W., Jr., K. J. Berry, and J. G. Medina, <br />1982: Climax I and II: distortion resistant residual <br />analyses. J. Appl. Meteor., 21, 788-792. <br />Mielke, P. W., Jr., and J. G. Medina, 1987: A design <br />for Evaluation of cloud seeding effects Oil streamflow ill <br />Morocco. Bureau of Reclamation, Denver, CO, 46 pp, <br />Rauber, R. M., R. D. Elliott, and A. W. Huggins, <br />1987: The SCPP targeting model, Filial repon for the sepp <br />meteorological alld statistical support. Electronic <br />Techniques, Inc., Fort Collins, CO, pp. 173.222. <br />Rhea, J. 0., 1978: Orographic precipitation model <br />for hydrometeorological use. Atmospheric Science Paper <br />No. '2B7, Colorado State University, Fort Collins, CO, <br />198 pp. <br />