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Title: Regimes of Diurnal Variation of Summer Rainfall over Subtropical East Asia

Abstract

Using hourly rain gauge records and Tropical Rainfall Measuring Mission 3B42 from 1998 to 2006, the authors present an analysis of the diurnal characteristics of summer rainfall over subtropical East Asia. The study shows that there are four different regimes of distinct diurnal variation of rainfall in both the rain gauge and the satellite data. They are located over the Tibetan Plateau with late-afternoon and midnight peaks, in the western China plain with midnight to early-morning peaks, in the eastern China plain with double peaks in late afternoon and early morning, and over the East China Sea with an early-morning peak. No propagation of diurnal phases is found from the land to the ocean across the coastlines. The different diurnal regimes are highly correlated with the inhomogeneous underlying surface, such as the plateau, plain, and ocean, with physical mechanisms consistent with the large-scale 'mountain-valley' and 'land-sea' breezes and convective instability. These diurnal characteristics over subtropical East Asia can be used as diagnostic metrics to evaluate the physical parameterization and hydrological cycle of climate models over East Asia.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
BROOKHAVEN NATIONAL LABORATORY (BNL)
Sponsoring Org.:
USDOE SC OFFICE OF SCIENCE (SC)
OSTI Identifier:
1048201
Report Number(s):
BNL-98146-2012-JA
Journal ID: ISSN 0894-8755; JLCLEL; R&D Project: 2014-BNL-EE631EECA-Budg; KP1703020; TRN: US201216%%797
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Climate; Journal Volume: 25; Journal Issue: 9
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; ASIA; CHINA; CHINA SEA; CLIMATE MODELS; DAILY VARIATIONS; INSTABILITY; METRICS; RAIN

Citation Formats

Yuan W., Lin W., Yu, R., Zhang, M., Chen, H., and Li, J.. Regimes of Diurnal Variation of Summer Rainfall over Subtropical East Asia. United States: N. p., 2012. Web. doi:10.1175/JCLI-D-11-00288.1.
Yuan W., Lin W., Yu, R., Zhang, M., Chen, H., & Li, J.. Regimes of Diurnal Variation of Summer Rainfall over Subtropical East Asia. United States. doi:10.1175/JCLI-D-11-00288.1.
Yuan W., Lin W., Yu, R., Zhang, M., Chen, H., and Li, J.. 2012. "Regimes of Diurnal Variation of Summer Rainfall over Subtropical East Asia". United States. doi:10.1175/JCLI-D-11-00288.1.
@article{osti_1048201,
title = {Regimes of Diurnal Variation of Summer Rainfall over Subtropical East Asia},
author = {Yuan W. and Lin W. and Yu, R. and Zhang, M. and Chen, H. and Li, J.},
abstractNote = {Using hourly rain gauge records and Tropical Rainfall Measuring Mission 3B42 from 1998 to 2006, the authors present an analysis of the diurnal characteristics of summer rainfall over subtropical East Asia. The study shows that there are four different regimes of distinct diurnal variation of rainfall in both the rain gauge and the satellite data. They are located over the Tibetan Plateau with late-afternoon and midnight peaks, in the western China plain with midnight to early-morning peaks, in the eastern China plain with double peaks in late afternoon and early morning, and over the East China Sea with an early-morning peak. No propagation of diurnal phases is found from the land to the ocean across the coastlines. The different diurnal regimes are highly correlated with the inhomogeneous underlying surface, such as the plateau, plain, and ocean, with physical mechanisms consistent with the large-scale 'mountain-valley' and 'land-sea' breezes and convective instability. These diurnal characteristics over subtropical East Asia can be used as diagnostic metrics to evaluate the physical parameterization and hydrological cycle of climate models over East Asia.},
doi = {10.1175/JCLI-D-11-00288.1},
journal = {Journal of Climate},
number = 9,
volume = 25,
place = {United States},
year = 2012,
month = 5
}
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