1,218 research outputs found
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WALLER CREEK STATUS REPORT 2002
This short report contains information on Waller Creek's estimated population, fecal coliform levels, land use distribution, mean baseflow, total phosphorus, and other water quality indicators.Water chemistry and biological data from Waller Creek were reviewed in order to evaluate temporal and spatial trends on this urban stream. The results of site analysis of variance indicated little discernable difference among sites and variability was high for conventional water chemistry constituents. Temporal trends were inconsistent with no notable degradation or improvements. Benthic macroinvertebrate surveys showed some significant site differences that appear to relate primarily to flow and possibly to nutrient enrichment. These surveys documented decreasing water quality over time; however, this result is apparently an artifact of the final survey, which took place after a long dry period. Overall, Waller Creek has low water quality and biological integrity when compared to other Austin area streams (worse than 75 percent of the watersheds for most measures).Waller Creek Working Grou
VAS sounding data evaluation
The VAS soundings derived by NOAA personnel and NASA personnel and rawinsonde soundings are compared: (1) directly by plotting on Skew t-log p diagrams; (2) by pairing rawinsonde soundings with the closest satellite soundings and calculating the mean and standard deviations of differences between the two data sets; and (3) by constructing synoptic and subsynoptic scale analyses with rawinsonde and satellite data. Differences for various parameters are discussed
Meteorological balloon Patent
Aerodynamically stable meteorological balloon using surface roughness effec
Rough surface improves stability of air- sounding balloons
Aerodynamic stability of balloons used for measuring the intensity and direction of atmospheric winds at various elevations is improved by incorporating a rough surface on the balloons. The rough-surfaced balloon is useful for collecting wind profiles and other meteorological data
Citizen Gain: The Economic Benefits of Naturalization for Immigrants and the Economy
Citizenship brings many benefits to immigrants, the opportunity to participate more fully in our democracy through the right to vote being primary among them. But beyond the clear civic gain is an often overlooked economic benefit: for a variety of reasons, naturalized immigrants are likely to see a boost in their family incomes that can benefit their children, their communities and the nation as a whole.Why is the economic importance of naturalization -- the process by which immigrants become citizens -- so often overlooked? Part of the reason is that much of the heated debate around the economic effects of immigration in the U.S. tends to focus on the unauthorized (or "illegal") population. The economic evidence in this arena points in multiple directions -- positive gains at an aggregate level, negative effects on specific sectors of the labor market, mixed impacts on government coffers -- but lost in that discussion is the fact that nearly three-fourths of all immigrants are either naturalized citizens or Lawful Permanent Residents (LPRs), those who have legal status and may be eligible to naturalize but have not yet done so. What would happen if those individuals who were eligible to naturalize actually chose to do so? How much would their economic situation improve -- and what would be the effects on the overall economy? If such gains are possible, how could policymakers help to encourage even higher rates of naturalization? In this policy brief, SIIS tackles these questions by combining individual-level data from the Census Bureau's 2010 Public Use Microdata Sample (PUMS) with the most recent data on the number of LPRs eligible to naturalize from the U.S. Office of Immigration Statistics (OIS). This brief begins with a review of the literature, drawing out both theory and evidence on why naturalization might be associated with a higher earnings trajectory. The authors then discuss the data used and the regression models developed; and make a number of choices along the way to insure that the estimates presented here are as conservative as possible. The brief then discuss how the wage trajectory might change over time -- benefits would actually accrue over a number of years -- and then examines the possible impacts on aggregate earnings and the overall economy.The brief concludes with a discussion of the policy implications, particularly how these benefits might be made clear to those who have not yet naturalized and how new financial and other vehicles could be used to induce higher levels of naturalization
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The Flow Permanence Index: A Statistical Assessment of Flow Regime in Austin Streams
The report makes two explicit mentions of Waller Creek, briefly mentioning flow patterns and how they are highest near its mouth. In addition, the report contains valuable information concerning the importance of baseflow in the sustainability of a creek ecosystem.Flow permanence or the reliability of baseflow in a stream is an important metric in determining the potential of local streams to support aquatic life and can be used to provide an indication of future ecological changes. This report looks at quantifying the probabilities associated with permanent flow at all streams monitored for the City of Austin Environmental Integrity Index. Spatial patterns in flow permanence were examined, as well as the contributions of rainfall to flow permanence. Among the principal results is an index and ranking of streams with the most and least consistently flowing monitoring sites and a heuristic to calculate the probability of flow in a stream given the cumulative rainfall in the previous three months.Waller Creek Working Grou
General purpose simulator system study
Modifications to computerized simulator system for space shuttle and space station application
The development of convective instability, wind shear, and vertical motion in relation to convection activity and synoptic systems in AVE 4
Data from the Fourth Atmospheric Variability Experiment were used to investigate conditions/factors responsible for the development (local time rate-of-change) of convective instability, wind shear, and vertical motion in areas with varying degrees of convective activity. AVE IV sounding data were taken at 3 or 6 h intervals during a 36 h period on 24-25 April 1975 over approximately the eastern half of the United States. An error analysis was performed for each variable studied
A preliminary assessment of the accuracy of selected meteorological parameters determined from Nimbus 6 satellite profile data
Published rms errors in rawinsonde data and discrepancies between satellite and rawinsonde profile data for temperature, dewpoint temperature, mixing ratio, and wind speed. Satellite rms errors were found to be 2 to 3 times as large as those for rawinsonde data. Gradients of the preceding parameters were computed for both rawinsonde and satellite data and compared with means and near extreme values computed from the AVE 2 and AVE 4 experiments. In all cases, it was found that satellite data can be used to determine with relatively good accuracy the near extreme gradients but not those whose value does not exceed the average. Synoptic charts were prepared to show that patterns of temperature could be determined with relatively good accuracy, while those of dew point were not as good as those for temperature. Winds represented by cloud motion vectors (satellite winds) were compared with rawinsonde winds, and it was found that large gaps exist in satellite values for a given pressure level and that errors in the satellite determined concluded that satellite profile data are very useful in synoptic analysis, particularly in data sparse regions as well as regions where near extreme gradients exist in the measured parameters
Determination of wind from NIMBUS 6 satellite sounding data
Objective methods of computing upper level and surface wind fields from NIMBUS 6 satellite sounding data are developed. These methods are evaluated by comparing satellite derived and rawinsonde wind fields on gridded constant pressure charts in four geographical regions. Satellite-derived and hourly observed surface wind fields are compared. Results indicate that the best satellite-derived wind on constant pressure charts is a geostrophic wind derived from highly smoothed fields of geopotential height. Satellite-derived winds computed in this manner and rawinsonde winds show similar circulation patterns except in areas of small height gradients. Magnitudes of the standard deviation of the differences between satellite derived and rawinsonde wind speeds range from approximately 3 to 12 m/sec on constant pressure charts and peak at the jet stream level. Fields of satellite-derived surface wind computed with the logarithmic wind law agree well with fields of observed surface wind in most regions. Magnitudes of the standard deviation of the differences in surface wind speed range from approximately 2 to 4 m/sec, and satellite derived surface winds are able to depict flow across a cold front and around a low pressure center
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