OCR Text |
Show Range. Since it is the station used as the control (denominator) in forming co the ratios, all other ratios except possibly Yampa, which is surrounded by a complicated terrain, would be expected to run rather low for these two categories, and, indeed they do. For categories 1 and 2, a precipitation shadow lcs from the high White River Plateau should lower Steamboat Springs precipitation relatively, and thus raise the other ratios, which it does. For direction 5, Marvine should have its strongest orographic snow from the White River Plateau, while direction 6 places Marvine in a local precip:ii itation shadow from the 10, 000 ft. MSL terrain immediately northwest, but no still in good general orographic lift. Thus, ratios should be high for Marvine for both categories 5 and 6 but highest for 5. However, considering the de0 ., creased orographic effect at Steamboat for 6. Marvine might have a higher ratio for 6. For direction 6, the orographic effect should decrease at Steam., N, 0 ~: boat Springs and increase at Yampa partly due to terrain funneling. Thus, ) o: all ratios should be fairly high with Yampa expected to show the largest increase as compared to direction 5. This verifies . t- ~. l'. • Q: ) ,i : ; 01The two seeded seasons of 1965-66 and 1966-67 were not used in the computation of the 10 year precipitation ratio calculations but were rather held out : ~; to be used as test cases for finding a possible seeding effect. A study of ; o: Table 11 reveals the largest anomaly (positive) of observed compared to predicted seasonal total precipitation at Walden for 1966-67 as compared to ~: all other stations and all other years studied. Checking for the possibility 01that Steamboat Springs might have been in an unexpected minimum precipitation zone, anomalies at Hayden and Yampa both indicate that Steamboat ~; had slightly more than expected precipitation, while Marvine indicates that 0: Steamboat might be slightly deficient. At any rate, there is no evidence that Steamboat Springs was severely deficient in precipitation (relative to the Ln i derived mesoclimatology established in this study) during 1966-67. Thus, it ~'. is possible that a positive seeding effect occurred downstream at Walden. 0 ' Walden-to-Steamboat precipitation ratios by direction categories revealed that the ratios for categories 2 and 3 were at record high levels for both 01 ~'. 1965-66 and 1966-67, with the latter season showing the highest values. 0 ' Other direction category ratios for Walden were not unusually high for these It should be noted, however, that ratios for a number of other 0 i two years. ('): stations for direction 2 were also quite high for these two years. oi 119 |