Back to Search
Start Over
Finescale Diurnal Rainfall Statistics Refined from Eight Years of TRMM PR Data.
- Source :
-
Journal of Applied Meteorology & Climatology . Feb2008, Vol. 47 Issue 2, p544-561. 18p. 2 Charts, 9 Graphs, 11 Maps. - Publication Year :
- 2008
-
Abstract
- The adequacy of hourly rainfall sampling was examined in terms of the detection of diurnal variations using 8 yr (1998–2005) of data observed by the precipitation radar on the Tropical Rainfall Measuring Mission (TRMM) satellite. It was found that the monthly and hourly rain samples for each 0.2° grid point over the 8-yr period are composed of multiple precipitation systems. In this study, a “3-h-significant diurnal peak” was defined as the time of maximum rainfall with consecutive positive anomalies for more than 3 h. The fraction of the analyzed area with a 3-h-significant diurnal peak increased annually and accounted for 43% of the total global tropics at 0.2° resolution over the 8-yr period. The diurnal signature over Tibet and the Amazon showed a high degree of spatial uniformity (at >10° scale). The degree of similarity and locations of the regional diurnal characteristics are described in terms of seasonal variations and at multiple resolutions based on spatial uniformity. For example, uniform early-afternoon peaks generally appear over the coastal land and areas of high relief, whereas a seasonally invariant early-afternoon peak over the low-lying Amazon basin is recognized as a regional characteristic. In areas of coastal ocean, early-morning peaks appear in certain regions such as the area surrounding the so-called Maritime Continent and the area off the west coast of Mexico. These peaks are distinct from the global characteristics of late-morning rainfall maxima recorded over most coastal oceans and early-morning peaks recorded over open ocean. The results are also compared with those derived from TRMM Microwave Imager (TMI) data. In addition to obtaining a coherent signal, regional differences in the timing of maximum rainfall over the Tibetan Plateau were addressed; this discrepancy is attributed to limitations of the scattering algorithm used for TMI data in terms of detecting shallow convection and screening cold surfaces. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 15588424
- Volume :
- 47
- Issue :
- 2
- Database :
- Academic Search Index
- Journal :
- Journal of Applied Meteorology & Climatology
- Publication Type :
- Academic Journal
- Accession number :
- 31549050
- Full Text :
- https://doi.org/10.1175/2007JAMC1559.1