Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 4 of 4
Full-Text Articles in Physical Sciences and Mathematics
Changing Fields: Agricultural Land Use Changes In Nebraska 1925-1974, Donald A. Wilhite
Changing Fields: Agricultural Land Use Changes In Nebraska 1925-1974, Donald A. Wilhite
Drought Mitigation Center: Faculty Publications
The series of graphs and maps which follow illustrate agricultural land use changes in Nebraska from 1925 to 1974. With these graphs and maps, the major agronomic crops of corn (dryland and irrigated), wheat, sorghum and soybeans are analyzed. The purpose of this analysis is to provide a pictorial history of Nebraska's ever-changing cropping system and, hopefully, to stimulate ideas and discussion with regard to trends and future directions. The Nebraska Water Resources Center is deeply interested in both the past and the future of Nebraska's agriculture because of the demands which agriculture places on the state's water resources. An …
Some Trends In Forecast Skill At The National Severe Storms Forecast Center, Allen Pearson, Steven J. Weiss
Some Trends In Forecast Skill At The National Severe Storms Forecast Center, Allen Pearson, Steven J. Weiss
United States Geological Survey: Staff Publications
Tornado watch and severe local storm outlook verification statistics reveal the trends in forecast skill at the National Severe Storms Forecast Center. The skill level of the outlook has been steadily increasing since 1973. The percentage of watches verifying has been gradually increasing since 1970. While the probability of detection for tornadoes has decreased slightly since 1974, this appears to be highly correlated with the number of outbreak tornadoes reported in a given year. During significant tornado days, a much higher degree of skill is exhibited for both outlooks and watches. Factors influencing the results are discussed, including the impact …
Turbulence Spectra Above A Vegetated Surface Under Conditions Of Sensible Heat Advection, Raymond P. Motha, Shashi B. Verma, Norman J. Rosenberg
Turbulence Spectra Above A Vegetated Surface Under Conditions Of Sensible Heat Advection, Raymond P. Motha, Shashi B. Verma, Norman J. Rosenberg
Drought Mitigation Center: Faculty Publications
Spectra of vertical and horizontal velocity, air temperature and humidity fluctuations were analyzed from measurements made over a well-watered alfalfa crop under conditions of sensible heat advection. Vertical velocity and air temperature spectra as well as cospectra of momentum, sensible heat and water vapor were found to be dependent on atmospheric thermal stratification. These spectra and cospectra were shifted toward higher frequencies under advective as compared to lapse conditions. These results indicate that the predominant eddy sizes are relatively smaller under advective conditions. Humidity spectra, on the other hand, were independent of daytime thermal stratification conditions but were influenced by …
Uranium Transport In The Walker River Basin, California And Nevada, Larry Benson, D. L. Leach
Uranium Transport In The Walker River Basin, California And Nevada, Larry Benson, D. L. Leach
United States Geological Survey: Staff Publications
During the summer of 1976 waters from tributaries, rivers, springs and wells were sampled in the Walker River Basin. Snow and sediments from selected sites were also sampled. All samples were analyzed for uranium and other elements. The resulting data provide an understanding of the transport of uranium within a closed hydrologic basin as well as providing a basis for the design of geochemical reconnaissance studies for the Basin and Range Province of the Western United States. Spring and tributary data are useful in locating areas containing anomalous concentrations of uranium. However, agricultural practices obscure the presence of known uranium …