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Title: Physical Determinants and Reduced Models of the Rapid Cooling of Urban Surfaces During Rainfall
Abstract

Using a detailed model, sensitivity analyses are conducted to identify the leading physical determinants and heat fluxes that control energy exchange between surface runoff and urban pavements during rainfall. These analyses confirm that pavement characteristics, such as albedo and thermal effusivity, strongly influence the initial temperature of the pavement before rain starts. Moreover, this sensitivity propagates to the runoff and pavement temperatures as well as to sensible heat and evaporation fluxes during and after rainfall. Heat transfer inside the runoff and pavement during rainfall is also very sensitive to the rain temperature and is the leading process in surface cooling (the classically important sensible and latent heat fluxes to the atmosphere are minor contributors). Finally, based on the findings from the sensitivity analyses, using a bulk energy approach, a reduced version of the full model is proposed. This simple model uses the spatially averaged temperatures of the runoff and pavement and can predict their temperatures and the associated energy fluxes almost as accurately as the full model. The reduced model has the added advantages of computational efficiency and simplicity of implementation in coarse earth system models.

 
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Award ID(s):
1664021
NSF-PAR ID:
10460146
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Journal of Advances in Modeling Earth Systems
Volume:
11
Issue:
5
ISSN:
1942-2466
Page Range / eLocation ID:
p. 1364-1380
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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