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Zuohao Cao and Jianmin Ma

.g., Garratt 1994 ) is the Obukhov length, which is defined as where T is the average temperature at two heights and g is the gravitational acceleration. The virtual temperature T v , is defined as It can be shown that L formulated in Eq. (5a) is equivalent to the following definition (e.g., Brutsaert 1982 ; Busch 1973 ; Cao and Ma 2005 ; Cao et al. 2006 ): In Eqs. (1) – (3) ψ m , ψ h , and ψ q are integral forms of the departure of wind speed, temperature, and moisture

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David A. Brooks

to a waveguide. Tropospheric ducting can provide strong-signal VHF pathsfar beyond the geometric horizon. The atmospheric index of refraction N is a functionof temperature, pressure and moisture content, expressed in the form (Bean and Dutton, 1968)where c~, c2 are constants, and T, p and q are,respectively, the temperature, pressure and partialpressure of water vapor. In the climatological-meanatmosphere, it is found that the vertical dependenceof N approximately follows an exponential law

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Biswadev Roy, Jeffrey B. Halverson, and Junhong Wang

. (9) 4. Results a. Overall RH correction Average daytime and nighttime vertical profiles of the uncorrected RH ( U m ) minus corrected RH ( U W02 ) values (the difference profile) are presented in Fig. 4 , which shows nighttime and daytime difference profiles for each site. The difference profiles show negative values mostly. This means that more moisture is added to the soundings. The daytime corrections include SAHE modification to the first 50 s of the sounding or up to about 200

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Jason A. Otkin, Derek J. Posselt, Erik R. Olson, Hung-Lung Huang, James E. Davies, Jun Li, and Christopher S. Velden

used to provide realistic fluxes of heat and moisture at the surface. For a complete description of the MM5 modeling system, the reader is referred to Grell et al. (1994) and Dudhia et al. (2003) . WRF is a sophisticated numerical model that solves the compressible nonhydrostatic Euler equations (cast in flux form) on a mass-based terrain-following coordinate system. The WRF model includes several microphysical, cumulus, and planetary boundary layer (PBL) schemes and also employs the recently

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Timothy J. Wagner, David D. Turner, Larry K. Berg, and Steven K. Krueger

longwave absorption of radiation by cumuli result in a net cooling of the environment. Of course, the environment in which these clouds form significantly affects their macrophysical and microphysical characteristics through the regulation of available heat and moisture. Cumuli mix with air from the environment through the entrainment process in which unsaturated environmental air is engulfed by and assimilated into the moist cloud environment. Entrainment impacts the cloud by reducing its liquid water

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Xue-Fa Wen, Xuhui Lee, Xiao-Min Sun, Jian-Lin Wang, Ya-Kun Tang, Sheng-Gong Li, and Gui-Rui Yu

is injected into an evaporation flask that is supplied continuously with dry air. In the flask, evaporation occurs instantly and completely to prevent any fractionation, so that the moisture stream exiting the flask has isotope ratios that are presumably identical to those of the source liquid water feed, the latter of which can be measured accurately according to the VSMOW-SLAP scale. The first such device, called a dripper, consists of a syringe pump that delivers the liquid water slowly into

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Jinpeng Fan

. Moisture. and Humidity 1985; Measurement and Control in Science and Industry. Proc. Int. Syrup. on Moisture and Humidity, Washington D.C., Instrument Society of America, 57-73.--., and T. Lalas, 1981a: The WMO Psychrometer. Div. 0f Appl. Physics Tech. Paper No. 3, Commonwealth Scientific and In dustrial Research Organization (CSIRO), Australia. (Also pub lished by CSIRO under the title "The WMO Reference Psy chrometer" for distribution by CSIRO and the World Meteo rological Organization

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Christopher A. Fiebrich, Cynthia R. Morgan, Alexandria G. McCombs, Peter K. Hall Jr., and Renee A. McPherson

process, such true meteorological phenomena can be distinguished from sensor problems. d. Soil moisture Soil moisture may be the most difficult variable to quality assure in a surface observing network. Its dependence on rainfall, evaporation, vegetation type and condition, slope, soil texture, and soil structure (e.g., compactness, profile) presents a wide range of possible correct values ( Hillel 1982 ; Illston et al. 2008 ). Numerous sensor technologies and methods for measuring soil moisture also

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Paul Schmid and Dev Niyogi

1. Introduction The planetary boundary layer (PBL) is the turbulent layer near the earth’s surface. Determining the PBL height is important because it is where any moisture, aerosol, or heat from the surface can be exchanged with the free atmosphere above. It is most commonly observed as an inversion in potential temperature and dewpoint, or as a peak in low-level wind ( Holzworth 1964 ; Grossman and Gamage 1995 ). The top can also be observed from a strong gradient in lidar backscatter

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Hung-Lung Huang and George R. Diak

moisture profiling of the atmospherefrom a microwave instrument a routine possibility. Inthe clear atmosphere, the primary absorbing constitc 1992 American Meteorological SocietyAUGUST 1992 HUANG AND DIAK 355 TABLE 1. AMSU-B (channels 16-20) noise values are intended torepresent the expected effective noise after averaging to AMSU-A(channels 1

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