Orographic Flow Response to Variations in Upstream Humidity

Autor:	Heather Dawn Reeves, Richard Rotunno
Rok vydání:	2008
Předmět:	Freezing level Atmospheric Science Materials science Meteorology Flow (psychology) Condensation Airflow Humidity Relative humidity Mechanics Lifted condensation level Orographic lift
Zdroj:	Journal of the Atmospheric Sciences. 65:3557-3570
ISSN:	1520-0469 0022-4928
DOI:	10.1175/2008jas2762.1
Popis:	The effects of upstream relative humidity (RH) on low-level wind and precipitation patterns for low-speed, statically stable flows over a mountain are investigated using idealized two- and three-dimensional numerical-simulation experiments in which RH is increased from 0% to 100%. For RH less than some critical threshold, the flow upstream becomes less decelerated as RH is increased; for RH greater than this threshold, the flow upstream becomes more decelerated as RH is increased. This increasing deceleration with RH is due to locally enhanced static stability resulting from enhanced condensation near the freezing level. Analyses from the simulations indicate that the lifted condensation level and the height of the freezing level are significant control parameters for the upstream-flow deceleration in the steady-state solutions. Dimensional analysis using these control parameters (as well as others) brings forth new nondimensional parameters that are shown to enter into analytic formulas for the orographic upstream-flow deceleration in a moist atmosphere.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::833aa9e7e6c4d3f70402c2e6b2f343b9 https://doi.org/10.1175/2008jas2762.1 Zobrazit plný text záznamu Plný text ve formátu PDF