摘要:

The American Geophysical Union was established in 1919 as the American Committee of the International Union of Geodesy and Geophysics, and its Executive Committee is the Committee on Geophysics of the National Research Council. The objects of the Union are to promote the study of problems concerned with the figure and physics of the Earth, to initiate and coordinate researches which depend upon international and national cooperation, and to provide for their scientific discussion and publication. In the accomplishment of these objects, the Union is divided into sections following the plan of organization of the International Union of Geodesy and Geophysics. There are now seven sections, namely, (a) Geodesy, (b) Seismology, (c) Meteorology, (d) Terrestrial Magnetism and Electricity, (e) Oceanography, (f) Volcanology, and (g) Hydrology. A Section of Geophysical Chemistry was discontinued May 31, 1924, as the International Union had failed to provide such a Section; the Section of Hydrology was established November 15, 1930—matters pertaining to scientific hydrology referred to the American Geophysical Union had been previously looked after by special committees on Hydrolog

ISSN:0002-8606    

DOI:10.1029/TR020i001p00001

年代:1939

数据来源: WILEY

摘要:

This paper does not include the flood of March 2, 1938, and all comparisons are to be so construed.The rivers of Los Angeles and San Bernardino counties are subject to destructive floods to a greater degree than are the streams in the remainder of the State. Torrential rains are almost characteristic of the drainage areas of the Los Angeles, San Gabriel, and Santa Ana rivers.

ISSN:0002-8606    

DOI:10.1029/TR020i001p00006-2

年代:1939

数据来源: WILEY

摘要:

On March 2, 1938, Southern California experienced a major flood, which equalled or exceeded any previous flood of record. Most recent figures made available through the courtesy of the United States Engineer Office at Los Angeles show that as a result of this flood 87 lives were lost and property was damaged to the extent of 79 million dollars. I would like to present to this meeting some of the rainfall‐ and runoff‐data pertaining to this flood as it has been collected by the Los Angeles County Flood Control Distr

ISSN:0002-8606    

DOI:10.1029/TR020i001p00008

年代:1939

数据来源: WILEY

摘要:

The purpose of this paper is to discuss briefly the functioning of debris‐control structures in this region and the loss of storage‐capacity due to the accumulation of debris in local flood‐control reservoirs. In considering these subjects it is, I believe, essential that we have some conception of the why and the wherefore of the debris‐problem as faced here in Los Angeles County. In less arid localities there is little relationship between control of floods and control of debris. Here in Southern California, in some instances, when we control debris‐movement we go a long way in controllin

ISSN:0002-8606    

DOI:10.1029/TR020i001p00016-2

年代:1939

数据来源: WILEY

摘要:

Mr. Hubert asked that I bring out the special problems relating to flood‐control in Southern California., and I was assigned the comprehensive subject of “Hydraulic design of flood‐control basins and channels.” I believe this covers a rather broad field and overlaps and includes, in a general way, the entire programs outlined for today and part of t

ISSN:0002-8606    

DOI:10.1029/TR020i001p00022

年代:1939

数据来源: WILEY

摘要:

We are at the beginning of a rapidly expanding program of reservoir‐construction for multiple purposes of irrigation, power, flood‐control, domestic water‐supply, and silt‐abatement. We may safely anticipate that this program will continue to expand until virtually all reservoirs for which there is a need and an economic Justification will be created and placed in operation. We may speculate that the peak in this program will be reached in about 10

ISSN:0002-8606    

DOI:10.1029/TR020i001p00026

年代:1939

数据来源: WILEY

摘要:

The High Plains region has been passing through a prolonged low in the precipitation‐cycle during a large part of the last decade. The drought has continued longer and has been more severe than any that has been experienced since the region began to be farmed. It has caused untold distress. Crops have failed for years in succession. In large areas in the so‐called dust‐bowl the top soil has been almost entirely removed by wind‐erosion and the dust‐storms have become so bad at times that the health of the inhabitants has been seriously threatened. In some parts of the region the annual rainfall, which ranges from about 18 to 24 inches, according to the location of the area, has returned to about the normal or long‐time average. In others the drought is still in progress and a partial or complete crop‐failure was again experienced in 1938. When the rainfall‐record is studied, it becomes apparent that a large part of the High Plains never should have been farmed and should be allowed to go back to the range, if indeed the native grasses can be restored. Other parts, however, can still be farmed with moderate success by the farmer who uses proper methods of cultivation and crop‐rotation, and combines farming with stock‐raising by keeping a part of his land in pasture and raising mostly feed‐crops. Irrigation, if it can be accomplished at a practicable cost, affords security both to the fa

ISSN:0002-8606    

DOI:10.1029/TR020i001p00032

年代:1939

数据来源: WILEY

摘要:

The Corps of Engineers, United States Army, was not assigned official charge of Federal flood‐control activities until the passage of the Flood‐Control Act of June 22, 1936. However, prior to that date, the Corps prepared thousands of flood‐control studies throughout the United States, and by special acts of Congress, 1910, 1917, and 1928, designed and constructed flood‐control improvements on the Mississippi and Sacramento rivers. It may be of interest to learn the reasons why the Corps of Engineers, acting through the Chief of Engineers and the Secretary of War, became the agency responsible for the design and construction of flood‐control works throughout the United States. The reasons are logical and are based upon the experience of m

ISSN:0002-8606    

DOI:10.1029/TR020i001p00035

年代:1939

数据来源: WILEY

摘要:

Floods have been with us since the dawn of history. Early records describe not only the destruction caused by floods, but also Man's ineffectual efforts to prevent great losses of life and property once the raging waters were upon him. While no one can deny the value of well‐conceived construction programs designed to protect property and lives from floods, it is important to realize that modern scientific research has clarified the contributing causes and encouraged us to take them into consideratio

ISSN:0002-8606    

DOI:10.1029/TR020i001p00042

年代:1939

数据来源: WILEY

摘要:

The State of California has a recognized interest in flood‐control of long standing. Through legislation, investigations and planning, and direct expenditure of State funds, it has actively assisted or participated in flood‐control since the Fifties.One of the most serious problems early confronting the pioneers who settled in the Sacramento and San Joaquin valleys, as well as in other sections of the State, was that of controlling floods. Far too commonly towns and agricultural lands bordering the streams were inundated by floods resulting in destruction of life and property. Individuals who sought to cope with the problem soon found it to be far beyond their ability and resources and it was realized that only by organized effort could the necessary resources be mustered to provide the protective works required. It was natural that these early pioneers should turn to the State for assista

ISSN:0002-8606    

DOI:10.1029/TR020i001p00046

年代:1939

数据来源: WILEY