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The chemical and biological components of rainwater a case study for the habitability of the atmosphere /Rust, Phillip Lloyd, January 2007 (has links) (PDF)
Thesis (M.S. in geology with a major in hydrogeology)--Washington State University, December 2007. / Includes bibliographical references (p. 57-67).
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Rainfall over coastal waters of the Pacific NorthwestReed, Ronald Keith 30 August 1972 (has links)
The objective of this study was to ascertain the magnitude and
distribution of rainfall over coastal waters of the northwestern United
States and to compare values with those at nearby land stations.
Precipitation was measured with gauges at Totem, rainfall amounts
were assessed from weather reports at lightships off the coast, and
precipitation frequencies at lightships and land stations were examined.
Results from the three methods were quite consistent; precipitation.
on at sea was only about one-third that at coastal land stations.
These values are appreciably less than previous estimates of oceanic
rainfall in this area, and they support the view that a significant
horizontal gradient of precipitation may exist between the coast and
open sea. Rainfall typically occurs both at sea and ashore on the
same day, but it rains fewer hours at sea. The relative amount of
rain at sea varies with the type of atmospheric system, and rainfall
at the coast appears to be intensified by frictional processes.
Estimates of evaporation minus precipitation are less negative
than earlier ones; consideration of their relation to surface salinity
leads to distributions that are in good agreement with oceanographic
knowledge. The newer values suggest that in this region the heat
gain by the atmosphere may be less (but moisture entrainment may
be greater) than was thought. / Graduation date: 1973
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A study of the relation between radar and raingage indicated rainfall over northern CaliforniaStrem, Eric Thomas 30 June 1975 (has links)
The WSR-57 weather radar operated by the National
Weather Service at Sacramento, California, plus a network
of precipitation gages provided data for this comparison
of radar reflectivity with precipitation rates. Located
in a valley with mountains within range of the radar on
three sides, this radar has varying sensitivity for
precipitation rates as a result of the terrain effects.
Variation in the terrain surrounding the radar has led
to a very wide scatter in precipitation rates associated
with any particular radar reflectivity. The radar failed
to detect precipitation up to 77% of the time over the
Coast Range at ranges greater than 100 nm. Linear
regression analyses revealed very poor correlation between
the raingage indicated precipitation rate and the radar
reflectivity. These analyses resulted in values of (R²),
the coefficient of determination, ranging from zero as
a minimum to only 0.502 as a maximum. Such results are
generally much poorer than results obtained by others.
The poor correlations and both overestimation and
underestimation of rainfall resulted from factors such
as range, terrain blocking, windward or leeward exposure,
freezing level height, beam height and width, and the
distribution of water vapor in the vertical. / Graduation date: 1976
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Comparitive snow accumulation and melt during rainfall in forest and clearcut plots in western Oregon /Berris, Steven Neil. January 1984 (has links)
Thesis (M.S.)--Oregon State University, 1985. / Typescript (photocopy). Includes bibliographical references (leaves 121-127). Also available online.
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An examination of precipitation variability with respect to frontal boundariesBrinson, Kevin R. January 2007 (has links)
Thesis (M.S.)--University of Delaware, 2007. / Principal faculty advisor: David R. Legates, Dept. of Geography. Includes bibliographical references.
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Rainfall temporal patterns and runoff at Coshocton, Ohio /Chukwuma, Godwin Ositadinma, January 1982 (has links)
Thesis (Ph. D.)--Ohio State University, 1982. / Includes bibliographical references (leaves 121-124). Available online via OhioLINK's ETD Center
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The Value of Pasture, Rangeland, Forage Rainfall Index Insurance to Texas RanchersMaisashvili, Aleksandre 2010 May 1900 (has links)
In the beginning of the 2007 crop year, the Federal Crop Insurance Corporation
(FCIC) launched the Pasture, Rangeland, Forage Rainfall Index Pilot Program (PRF-RI)
for six states. This insurance is an index and not individual insurance. Risk Management
Agency officials claim that PRF-RI insurance mitigates the risk because index and
forage production move in the same direction. Therefore when the index is low there is
the expectation that production will also be low. PRF-RI is a pilot program and ranchers
are skeptical as to whether or not it is viable to purchase the insurance.
The objective of this research was to determine the economic benefits of rainfall
insurance in selected counties in Texas and estimate the probability of indemnities under
different types of coverage levels and index intervals.
Historical rainfall indices were simulated for all index intervals and a
multivariate empirical distribution of rainfall indices were used. The model was run for
alternative scenarios on the available coverage levels (90%, 85%, 80%, 75%, 70%) and
relevant premium rates. Each scenario resulted in an estimate of the insurance benefits variable probability density function for a particular coverage level. Stochastic
Dominance with Respect to a Function (SDRF), Stochastic Efficiency with Respect to a
Function (SERF), and StopLight chart were used to rank the benefits of alternative
coverage levels.
The results indicated that for all regions tested, the best alternative when
purchasing PRF-RI was to buy the 90% coverage level. Probabilities of earning net
indemnities decreased at lower coverage levels. December-January is a critical time
period that should be taken into consideration by the ranchers. The results indicated also
that insurance returns depend on the region where the policy is purchased. In southern
and eastern parts of Texas net indemnities appeared to be significantly less and have
lower probabilities of being positive than in West Texas. Ranchers from West Texas
may be able to significantly benefit from the insurance.
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The use of large plot rainfall simulation to investigateSorenson, Joshua Russell 12 April 2006 (has links)
In this study, large scale rainfall simulation was used to evaluate runoff generation from canopy
and intercanopy areas within an ashe juniper woodland of the Edwards Plateau. One 3 x 12 m site was
established beneath the canopy of mature ashe juniper trees and two sites were established in intercanopy
areas. At the base of each plot a trench was constructed for capturing and monitoring shallow subsurface
flow. Rainfall simulations on the juniper site produced little surface runoff even though rainfall intensity
exceeded 145mm/hour on some occasions. A total of 82.6% of the water applied to the juniper dominated
site was accounted for as shallow subsurface flow. The dynamic nature of shallow subsurface flow
indicate this process is driven chiefly by macropore flow. On the intercanopy site, 12.67% of the water
left the site as surface runoff and ≤3% left as shallow subsurface flow. Large root channels and conduits,
which were not present on the intercanopy site, within the soil may promote shallow subsurface flow
beneath the juniper canopy. This study is the first to document and suggest shallow subsurface flow
occurs on Texas rangelands. The results of this experiment indicate shallow subsurface flow is an
important mode of runoff generation on the Edwards Plateau.
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The use of a rainfall simulator for brush control research on the Edwards Plateau region of TexasPorter, Shane Courtney 12 April 2006 (has links)
The thicketization of the semi-arid region of the United States has resulted in a dramatic
change allowing invasive woody species to dominate the landscape with an unknown
impact to the water budget. This landscape transformation has created a need to study
the hydrology of the region and in particular the effects of increased brush on the water
cycle. To study the effects of invasive brush on the water budget, a portable abovecanopy
rainfall simulator was developed for plot scale hydrologic research. The rainfall
simulator was tested at various field locations, including within the Edwards Plateau, to
replicate natural rainfall events on typical hillslope-scale plots. The rainfall simulator
was used to quantify aspects of the water budget for a 7 m by 14 m research plot on the
Edwards Plateau in Texas. Three rainfall simulation dates were selected for detailed
hydrologic analysis. Overall, throughfall accounted for 74% of the water applied to the
plot, while 26% of applied water was in the form of stemflow. Lateral subsurface flow
represented 33% of the water measured leaving the research plot. A notable result of
rainfall simulations was extensive lateral subsurface flow and no surface runoff. The
rainfall simulator has proven to be a cost-effective and efficient research tool for
replicating natural rainfall in arid and semi-arid environments.
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Modeling of runoff-producing rainfall hyetographs in Texas using L-moment statisticsAsquith, William Harold, Sharp, John Malcolm, January 2003 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2003. / Supervisor: John M. Sharp. Vita. Includes bibliographical references. Also available from UMI.
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