Main Title |
Mixing heights, wind speeds, and potential for urban air pollution throughout the contiguous United States / |
Author |
Holzworth, George C.,
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Other Authors |
|
CORP Author |
Environmental Protection Agency, Research Triangle Park, N.C. Office of Air Programs. |
Publisher |
United States Environmental Protection Agency, Office of Air Programs, |
Year Published |
1972 |
Report Number |
EPA450R72102; AP-101 |
Stock Number |
PB-207 103 |
OCLC Number |
00305516 |
Subjects |
Urban climatology--United States ;
Weather forecasting--United States ;
Boundary layer (Meteorology) ;
Air--Pollution--United States ;
Synoptic climatology--United States ;
Mathematical models ;
Models, Theoretical ;
Models, Theoretical--United States ;
Weather--United States
|
Additional Subjects |
Synoptic climatology--United States ;
Urban climatology--United States ;
Air--Pollution--United States ;
Boundary layer (Meteorolgy) ;
( Air pollution ;
Atmospheric motion) ;
( Urban areas ;
Atmospheric motion) ;
Forecasting ;
Temperature inversions ;
Wind(Meteorology) ;
Climatology ;
Seasonal variations ;
Mixing ;
Graphs(Charts) ;
Wind velocity ;
Dispersing ;
Air pollution forecasts ;
Air pollution episodes
|
Internet Access |
|
Holdings |
Library |
Call Number |
Additional Info |
Location |
Last Modified |
Checkout Status |
EHAD |
EPA AP-101 |
|
Region 1 Library/Boston,MA |
01/04/2016 |
EKBD |
EPA-AP-101 |
c.1, with errata |
Research Triangle Park Library/RTP, NC |
07/10/2019 |
STATUS |
EKBD |
EPA-AP-101 |
c.2 |
Research Triangle Park Library/RTP, NC |
07/10/2019 |
ELBD ARCHIVE |
EPA 450-R-72-102 |
Received from HQ |
AWBERC Library/Cincinnati,OH |
10/04/2023 |
DISPERSAL |
ELCM |
QC983.H64 1972 |
|
NVFEL Library/Ann Arbor, MI |
01/02/1998 |
NTIS |
PB-207 103 |
Some EPA libraries have a fiche copy filed under the call number shown. |
|
07/26/2022 |
|
Collation |
xi, 118 pages illustrations, tables, maps, 28 cm |
Abstract |
There is interest in pertinent climatological information and an overall appraisal thereof in terms of quantitative pollution potential. As used here, the potential for urban air pollution refers to certain meteorological factors that generally are important in the transport and diffusion of pollutants emitted by myriad but non-trivial sources in urban complexes. The mixing-layer height and the average wind speed within the mixing layer were calculated twice for each day of a 5-year record of upper air observations at 62 National Weather Service stations in the contiguous United States. These calculations illustrate the typical large diurnal variation in atmospheric dispersion. Twenty charts present seasonal and annual, and morning and afternoon mean mixing heights and wind speeds. A model of some general dispersion features over urban areas is described in which the normalized pollutant concentration averaged over a city is a function of mixing height, wind speed, and city size (distance the wind travels across the city). Isopleths of the total number of episode-days for episodes lasting at least 2 days and at least 5 days with various limiting mixing-height and wind-speed values are presented in 20 charts. (Author) |
Notes |
"January 1972" -- title page Title from title page Includes bibliographical references (pages 117-118). |
Contents Notes |
The mixing-layer height and the average wind speed within the mixing layer were calculated twice for each day of a 5-year record of upper air observations at 62 National Weather Service stations int he contiguous United States. The times of day of these calculations are morning and mid-afternoon. A rough allowance was made for effects of the urban "heat island" on the morning mixing heights. The morning and afternoon times coincide approximately with those of maximum and secondary minimum concentrations of slow-reacting pollutants in cities. These calculations illustrate the typical large diurnal variation in atmospheric dispersion. Twenty charts present seasonal and annual, and morning and afternoon mean mixing heights and wind speeds. A model of some general dispersion features over urban areas is described in which the normalized pollutant concentration averaged over a city is a function of mixing height, wind speed, and city size (distance the wind travels across the city). Frequency values of mixing height by wind speed are used with the model to calculate average normalized concentration frequencies for each weather station. Thirty charts present isopleth analyses of seasonal and annual, and morning and afternoon normalized pollutant concentrations that were exceeded 10, 25, and 50 percent of the time for specified city sizes. The occurrence of episodes during which upper limits on mixing height and wind speed were not exceeded were determined from the daily morning and afternoon values of these parameters. Isopleths of the total number of episode-days for episodes lasting at least 2 days and at least 5 days with various limiting mixing-height and wind-speed values are presented in 20 charts. |