A Statistical Study on Rain Characteristics of Tropical Cyclones Using TRMM Satellite Data

Abstract

Three-dimensional rain characteristics of tropical cyclones (TCs) are statistically quantified, using Tropical Rainfall Measuring Mission (TRMM) data from December 1997 to December 2003. Tropical cyclones are classified into four maximum intensity classes (Ͻ34, 34-64, 64-128, and Ն128 kt) and three stages (developing, mature, and decaying). First, rain characteristics of TCs are compared with those of the equatorial (10°N-10°S) mean. A notable finding here is that the average stratiform rain ratio (SRR), which is the contribution from stratiform rain in the total rainfall, of TCs is 52%, while it is 44% for the equatorial oceanic mean and 46% for the Madden-Julian oscillation in its mature phase. Stronger rain is observed in TCs both for convective and stratiform rain. Second, radial rain characteristics of TCs suggest that the region 0-60 km can be classified as "the inner core," and 60-500 km as "the rainband." The inner core is characterized with small SRR, very high rain-top height, and a large flash rate, indicating the vigor of convective activity. In contrast, the rainband is characterized with large SRR and relatively large rain yield per flash, indicating a large rainfall amount with a moderate convective activity. An important implication of this study is that TCs are listed in the high end of tropical oceanic organized rain systems, in terms of the organization levels of rain. Last, we use the above composite results to calculate the rainfall contribution of TCs to total annual rainfall between 35°N and 35°S as 3.3% Ϯ 0.1%.

Comparison of TRMM Rain-Rate Retrievals in Tropical Cyclones

“…Yokoyama and Takayabu (2008) demonstrated that TMI 2A12 substantially over-estimated the mean rain rates, compared to PR 2A25. The differences were greater than a factor of two in the 110 to 240 km region of major hurricanes, and greater than a factor of 1.5 for weaker TCs.…”

“…Alternatively, this paper assesses the retrieval characteristics specifically for tropical cyclones. Yokoyama and Takayabu (2008) estimate that 3.3% of the rain in the TRMM domain (35°S to 35°N) falls in tropical cyclones (TCs).…”

“…Lonfat et al (2004) and Chen et al (2006) used earlier versions of TMI 2A12 and PR 2A25, Yokoyama and Takayabu (2008) used PR 2A25 Version 5 and TMI 2A12 Version 5, Cecil (2007) used RSS V03, and Wingo and Cecil (2008) used RSS V04. Yokoyama and Takayabu (2008) presented compelling evidence that PR 2A25 Version 5 more effectively distinguishes between convective and stratiform rain than Version 6, with very high stratiform rain rates (> 10 mm h -1 ) occurring much more often in Version 6 than in Version 5. This paper only considers Version 6 of both 2A12 and 2A25 because those are the current versions of the standard TRMM algorithms and the older versions are not readily available.…”

Rainfall Variations Due to Twin Typhoons over Northwest Pacific Ocean

“…Rainfall intensity increases with its typhoon intensity (Prat and Nelson 2012 [19]). Typhoons have stronger convective rain in the inner core as well as stronger stratiform rain in the rain band than cloud clusters (Chie and Yukari 2008 [20]). The heaviest precipitation generally took place in the front of a typhoon and the asymmetry in typhoon precipitation varies with typhoon intensity (Lonfat et al, 2004 [12]), more asymmetric precipitation distribution occurs for weaker the typhoon.…”

A Framework for Moving Sensor Data Query and Retrieval of Dynamic Atmospheric Events

“…From published scientific journal papers [6][7][8][9][10], one observes that such a capability is extremely important to scientists who retrieve specific sensor data of specific atmospheric events for statistical analysis. Some query examples derived from these published scientific papers that require search, retrieval, and analysis of satellite data containing cyclone features, are listed below: Our problem is fundamentally different from previous research to discover and track cyclones from either sea-level pressure fields [11] or from heterogeneous satellite data [12].…”