摘要:

At Sapporo, the prefectural capital of Hokkaido, the northernmost island of Japan, winter lasts four months, snowfall is abundant, and conditions are ideal for the study of snow‐crystals and snow‐drift.In 1932 Professor Nakaya began to make a detailed study of the physical aspects of snow‐crystals, conducting observations and experiments both in the field and in the labor

ISSN:0002-8606    

DOI:10.1029/TR021i001p00097

年代:1940

数据来源: WILEY

摘要:

In the above comparison the forecast‐figures were for probable runoff of rivers and rise of Lake Tahoe. The possible minimum estimate which is always given on the regular actual forecast‐reports is based on assuming a considerable deficiency in spring and summer precipitation. Actually in 1939 the April–May precipitation at Tahoe City was only about 54 per cent of normal and April–June and April–July only 49 per cent of normal. The deficiency, especially in the April–May period, most of which was in April, helps to account for the deficiency in the runoff of the Truckee River. Had this spring precipitation been normal, the rise of Tahoe and runoff of the Walker and Carson rivers would have been noticeably above t

ISSN:0002-8606    

DOI:10.1029/TR021i001p00099

年代:1940

数据来源: WILEY

摘要:

During the winter of 1938–39, 32 different organizations cooperated in the making of snow‐surveys in California. These organizations are segregated as follows: National forests, 10; National parks, 4; irrigation‐districts, 6; municipal districts, 4; private companies, 2; power‐companies, 2; State agencies, 3; and Federal agencies, 1. Coordinated, standardized, and supervised by the State Division of Water Resources, the snow‐surveys were made at 183 snow‐courses and, from the data gathered, forecasts were made on 17 different watersheds at 51 runoff stations. Many of these forecasts are based on only a few years' data and are still in the experimental stage, but 28 were considered as being sufficiently reliable for

ISSN:0002-8606    

DOI:10.1029/TR021i001p00100-2

年代:1940

数据来源: WILEY

摘要:

A short statement has been requested as to the experience of the year 1939 in forecasting runoff from snow. In the Department of Water and Power of the City of Los Angeles, the final estimate is usually the average of the consistent results of several methods of approach, wild answers being discarded. The approach is usually by means of years of similar mean water‐content values; by treating each course separately, as if it were the only one in the basin, and then averaging the results; by obtaining an adjusted basin normal water‐content by correction for elevation‐areas; and by means of the “State direct

ISSN:0002-8606    

DOI:10.1029/TR021i001p00101

年代:1940

数据来源: WILEY

摘要:

The Edison Company's Big Creek hydroelectric development is served by three storage‐reservoirs, namely, Huntington, Florence, and Shaver Lakes, which impound the runoff of Bear Creek, Mono Creek, South Fork San Joaquin River, Big Creek, Pitman Creek, and Stevenson Creek. The combined area of the six drainage‐basins is 449 square miles, 45 per cent of which is above an elevation of 10,000 feet. For the past 12 years, runoff‐predictions for this area, based on a function of the preCipitation received at several stations at various altitudes, have shown the following errors:March 1 Maximum error 23 per cent, average error 4.6 per centApril 1 Maximum error 18 per cent, average error 8.5 per centMay 1 Maximum error 13 per cent, average error 7.0 pe

ISSN:0002-8606    

DOI:10.1029/TR021i001p00102

年代:1940

数据来源: WILEY

摘要:

In Colorado we have two interesting watersheds, namely, the Arkansas and the Poudre. For the former, the water‐content and runoff for 1936, 1937, 1938, and 1939 correlate within very narrow limits, well within five per cent deviation for the Tennessee Pass snow‐course records. Also a good relationship is shown by using the Hoosier Pass snow‐course records which are for an adjacent drainage‐basin. If all our surveys were as consistent as Tennessee Pass, East Portal Twin Lakes Tunnel, and Hoosier Pass, with respect to runoff, we could feel highly pleased with our work.However, we find some of the data considerably out of line as is evident by the records for the Poudre drainage. For the Arkansas forecast‐curve, no correction for precipitation has been applied while for the Poudre we have attempted to so correct the water‐content as to better align the plotted points. With such an adjustment we are able to fix a line showing a deviation of about

ISSN:0002-8606    

DOI:10.1029/TR021i001p00103

年代:1940

数据来源: WILEY

摘要:

In 1938, on April 1, the snow‐pack in the Fort Peck headwaters area was 116 per cent of “normal”. However, in view of the dry conditions which had persisted through 1937, and in anticipation of a continued deficiency in precipitation, it was predicted that the runoff above Fort Peck during the four‐month period, April to July, 1938, would be only approximately 50 per cent of “normal”. This forecast was not subsequently revised. Actually, the precipitation which occurred was above “normal” (130 per cent of “normal”) for the first time in several years, and the resulting runoff was 89 p

ISSN:0002-8606    

DOI:10.1029/TR021i001p00104-2

年代:1940

数据来源: WILEY

摘要:

In a general way, runoff in British Columbia followed the trend indicated by snow‐cover measurements, as outlined in my “Report on British Columbia snow‐surveys and runoff probabilities” of April 6, 1939. The above‐normal snow water‐content reported for the coastal belt was reflected in runoff above normal. In the Kootenay and Columbia River basins as mentioned in the above report, the snow water‐content varied considerably but averaged about normal; the runoff, however, was fairly consistently below normal, being about 90 per cent. Data subsequent to the report of April 6 caused a downward revision of some forecasts. Where the changes were material, the interested authorities were notifie

ISSN:0002-8606    

DOI:10.1029/TR021i001p00105

年代:1940

数据来源: WILEY

摘要:

In order to prevent snow from freezing to the sampling tubes it has, for many years, been customary to shellac the tubes. Apparently it has been general practice, at least in the Sierra Nevada region, to use only white shellac for this purpose.I followed this practice until one season I was unable to obtain white shellac and was compelled to substitute orange. I found that it worked equally well and showed better on the tube, making it much easier to determine when a thorough job had been done. It has been our experience that, under certain weather‐conditions, even a small spot that is not properly coated will cause plugging of the sample

ISSN:0002-8606    

DOI:10.1029/TR021i001p00108

年代:1940

数据来源: WILEY

摘要:

The following forms, used for reports from the field and for office‐records in connection with our cooperative snow‐surveys, are being submitted for suggestions that may be helpful to those interested in this type of work.These forms are self‐explanatory and should need no special comment. The form entitled “Survey notes” is derived largely from Dean George D. Clyde of Utah State Agricultural College a

ISSN:0002-8606    

DOI:10.1029/TR021i001p00109

年代:1940

数据来源: WILEY