A diagnostic study of the asymmetric distribution of rainfall during the landfall of typhoon Haitang (2005)

Abstract

The precipitation during landfall of typhoon Haitang (2005) showed asymmetric structures (left side/right side of the track). Analysis of Weather Research and Forecasting model simulation data showed that rainfall on the right side was more than 15 times stronger than on the left side. The causes were analyzed by focusing on comparing the water vapor flux, stability and upward motion between the two sides. The major results were as follows: (1) Relative humidity on both sides was over 80%, whereas the convergence of water vapor flux in the lower troposphere was about 10 times larger on the right side than on the left side.(2) Both sides featured conditional symmetric instability [MPV (moist potential vorticity) <0], but the right side was more unstable than the left side. (3) Strong (weak) upward motion occurred throughout the troposphere on the right (left) side. The Q Q Q vector diagnosis suggested that large-scale and mesoscale forcing accounted for the difference in vertical velocity. Orographic lift and surface friction forced the development of the asymmetric precipitation pattern. On the right side, strong upward motion from the forcing of different scale weather systems and topography caused a substantial release of unstable energy and the transportation of water vapor from the lower to the upper troposphere, which produced torrential rainfall. However, the above conditions on the left side were all much weaker, which led to weaker rainfall. This may have been the cause of the asymmetric distribution of rainfall during the landfall of typhoon Haitang.Citation: Yue, C. J., S. T. Gao, L. Liu, and X. F. Li, 2015: A diagnostic study of the asymmetric distribution of rainfall during the landfall of typhoon Haitang (2005).

Upper Ocean Response to Typhoon Kalmaegi and Sarika in the South China Sea from Multiple-Satellite Observations and Numerical Simulations

“…Figure 12 shows that high rainfall rates occurred on the left side of Typhoon Sarika's track. Many studies have shown that the remarkable asymmetric TC rainfall distribution is caused by the vertical wind shear, tropical cyclones motion, and water vapor flux or topography, in which the vertical wind shear is the primary factor [46][47][48][49][50][51][52][53]. Moreover, the rainfall maximum in the inner-core region of a TC is always located on the downshear left side for TCs in the Northern Hemisphere regardless of the storm motion and shear orientation [52,53].…”

The Spatial Characteristics of Hourly Rainfall Induced by Tropical Cyclones Along the South China Coast

“…The leading factors which have a significant impact on both the amount and distribution of rainfall associated with landfalling TCs are the following: (a) TC intensity, (b) TC distance to the station, and (c) TC azimuth relative to the station, respectively (Dominguez & Magaña, 2018;Yu & Wang, 2018;Yue et al, 2015). The high intensity TC type mostly appears along the coastline and gradually decreases toward the inland areas.…”

“…All rights reserved. Yue et al, 2015). The high intensity TC type mostly appears along the coastline and gradually decreases towards the inland areas.…”

“…Therefore, a better understanding of the factors that control the TCs' rainfall distribution is crucial for real-time operational rainfall forecasts. Some research studies on landfalling TC-rainfall presented that the amount of rainfall was often more substantial to the right side of the TC track as compared to the left in the north hemisphere owing to the dissimilar surface friction when TC approached the coast (Miller, 1964;Yue et al, 2015). The rainfall distribution caused by TC is asymmetric and mainly concentrates on one side of the TC track (Corbosiero & Molinari, 2003;Deng & Ritchie, 2018).…”

Spatial and temporal heterogeneity of tropical cyclone precipitation over China from 1959 to 2018

“…There are substantial discrepancies between the different regions affected by TCP over China due to the complex terrain and various climate characteristics (Yue et al, 2015;Qiu et al, 2019). Previous studies have pointed out that mountainous terrain can increase the intensity of TCP (Jiang et al, 2018;Chen et al, 2019).…”