NASA Scientific and Technical Aerospace Reports

to reduce stormwater runoff volume and pollutant loadings. Specifically, the paper focuses on the use of LID on commercial
and institutional land uses in urbanized areas. The paper first introduces some of the background issues associated with LID,
including the history of stormwater management, an understanding of stormwater as it relates to the hydrologic cycle, and a
discussion of associated stormwater management issues. Part 2 of the paper discusses the regulatory framework for stormwater
management, including national and local policies. Part 3 introduces LID and examines the particular methods appropriate for
commercial or institutional land uses in urbanized areas: bioretention, permeable pavements, and rain barrels. Case studies of
urban LID projects are presented in Part 4. Part 5 discusses the obstacles to implementing LID and possible ways to encourage
it, specifically through stormwater utility credits. The final section presents conclusions and recommendations. Although LID
was initially developed in a low-density residential setting, the case studies reviewed in this paper suggest that LID methods
can reduce stormwater runoff volume and pollution in urban areas with medium and high-density land uses. Additionally, the
LID methods can be adapted for use on large commercial and institutional land uses. This paper provides an overview of
relevant cases and a better understanding of LID implementation for property owners and municipalities. (4 tables, 5 figures,
41 refs.)
DTIC
Cities; Drainage; Environment Management; Land Use; Management Planning; Rain
20040112011 NASA Langley Research Center, Hampton, VA, USA
Cloud Detection Using Measured and Modeled State Parameters
Yi, Y.; Minnis, P.; Huang, J.; Ayers, J. K.; Doelling, D. R.; Khaiyer, M. M.; Nordeen, M. L.; [2004]; 4 pp.; In English; 13th
AMS Conference on Satellite Oceanography and Meteorology, 20-24 Sep. 2004, Norfolk, VA, USA; Original contains color
illustrations
Contract(s)/Grant(s): DE-A102-97-ER-62341; DE-A102-02ER-63319; No Copyright; Avail: CASI; A01, Hardcopy
In this study, hourly RUC analyses were used to examine the differences between RH and temperature values from RUC
reanalysis data and from radiosonde atmospheric profiles obtained at the ARM SCF. The results show that the temperature
observations from the SONDE and RUC are highly correlated. The RHs are also well-correlated, but the SONDE values
generally exceed those from RUC. Inside cloud layers, the RH from RUC is 2-14% lower than the RH from SONDE for all
RUC layers. Although the layer mean RH within clouds is much greater than the layer mean RH outside cloud or in the
clear-sky, RH thresholds chosen as a function of temperature can more accurately diagnose cloud occurrence for either dataset.
For overcast clouds, it was found that the 50% probability RH threshold for diagnosing a cloud, within a given upper
tropospheric layer is roughly 90% for the Vaisala RS80-15LH radisonde and 80% for RUC data. While for the partial cloud
(cloud amount is less than 90%), the RH thresholds of SONDE are close to RUC for a given probability in upper tropospheric
layers. The probabilities of detecting clouds at a given RH and temperature should be useful for a variety of application such
as the development of new cloud parameterizations or for estimating the vertical profile of cloudiness underneath a given cloud
observed from the satellite to construct a 3-D cloud data set for computing atmospheric radiative heating profiles or
determining potential aircraft icing conditions.
Author
Mathematical Models; Cloud Cover; Parameterization; Meteorology; State Estimation
20040120849 National Center for Atmospheric Research, Boulder, CO, USA
Free Oscillations of Deep Nonhydrostatic Global Atmospheres: Theroy and a Test of Numerical Schemes
Kasahara, A.; Jan. 2004; 88 pp.; In English
Report No.(s): PB2004-105846; NCAR/TN-457-STR; No Copyright; Avail: CASI; A05, Hardcopy
This report describes a method of calculating the modes of small-amplitude free oscillations of a compressible, stratified,
rotating deep atmosphere, confined between two concentric spheres, including sin phi and cos phi Coriolis terms, where phi
is the latitude. Unlike the Laplace-Taylor problem for the hydrostatic primitive equations that can be solved by the separation
of variables, the present problem is non-separable. In this study, normal mode solutions are obtained numerically by setting
up an eigenvalue-eigenfunction matrix problem by the combination of a spherical harmonics expansion in the horizontal
direction and a finite-difference discretization in the radial direction. A Test of the numerical schemes is conducted for an
isothermal basic state with a constant gravitational acceleration. In order to identify the species of solutions, a shallow
atmosphere version of the same formulation is considered in parallel.
NTIS
Atmospheric Models; Hydrostatics; Matrices (Mathematics)
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