scholarly journals Development and Formation Mechanism of the Southeast Asian Winter Heavy Rainfall Events around the South China Sea. Part I: Formation and Propagation of Cold Surge Vortex*

2015 ◽  
Vol 28 (4) ◽  
pp. 1417-1443 ◽  
Author(s):  
Tsing-Chang Chen ◽  
Jenq-Dar Tsay ◽  
Jun Matsumoto ◽  
Jordan Alpert
Keyword(s):  
South China Sea ◽  
South China ◽  
Heavy Rainfall ◽  
The Philippines ◽  
The South China Sea ◽  
The South ◽  
Cold Surge ◽  
China Sea ◽  
Flow Type ◽  
Development Processes

Abstract Examination of the development of cold season heavy rainfall/flood (HRF) events around the South China Sea (SCS) from their parent cold surge vortices (CSVs) shows three new development processes. First, the formation mechanism of the parent CSV of an HRF event [CSV(HRF)] has a preference as to geographic location, flow type of the cold surge inside the SCS, and time of day. The surface trough east of the Philippines, Taiwan, and southern Japan island chain in late fall and the near-equator trough across Borneo in winter facilitate the CSV(HRF) formation in two regions—the vicinity of the Philippines and Borneo. The formation of the Philippine (Borneo) CSV(HRF) occurs at 0600 UTC (0000 UTC) with involvement from the Philippine Sea (PHS)-type (SCS type) of cold surge flow. Second, the flow type of the cold surge determines the CSV(HRF) propagation across the South China Sea. The PHS-type (SCS type) facilitates (hinders) the CSV(HRF) westward propagation. This occurs because the easterly (northerly) flow is greater than (less than) the northerly (easterly) flow at the maximum isotach location of the cold surge flow associated with CSV(HRF) and is centered east of the demarcation line for propagation. This flow-type contrast is substantiated by the vorticity budget analysis for CSV(HRF). The positive 925-hPa vorticity tendency is located west of (coincident with) the 925-hPa vorticity center for the PHS-type (SCS type) of cold surge. Third, the CSV(HRF) development into a HRF event is achieved through multiple interactions of former vortices with sequential cold surges across the South China Sea. The first two CSV(HRF) development processes are reported herein; the last process is presented in Part II.

scholarly journals Development and Formation Mechanism of the Southeast Asian Winter Heavy Rainfall Events around the South China Sea. Part II: Multiple Interactions*

2015 ◽  
Vol 28 (4) ◽  
pp. 1444-1464 ◽  
Author(s):  
Tsing-Chang Chen ◽  
Jenq-Dar Tsay ◽  
Jun Matsumoto
Keyword(s):  
South China Sea ◽  
South China ◽  
Heavy Rainfall ◽  
Cold Season ◽  
The South China Sea ◽  
Northwestern Pacific ◽  
The South ◽  
Cold Surge ◽  
China Sea ◽  
Multiple Interactions

Abstract About 44% of the cold-season heavy rainfall/flood (HRF) events around the South China Sea require six days or longer to develop from the formation time of their parent cold surge vortices (CSVs). Formations for both the parent CSV and HRF event are involved with interactions of the concerned vortices with two different cold surge flows. The occurrence frequency of the East Asian cold surge flow varies from 4.5 to 6 days. The longevous CSVs enable their developments to interact with the second cold surge flows between formations of these CSVs and HRF events. Two requirements for the formation of HRF events are 1) synchronized occurrence of the HRF event and the northwestern Pacific explosive cyclone and 2) simultaneous occurrence of the maximum speeds among westerlies of the northwestern Pacific explosive cyclone and easterlies of the tropical trade winds and the HRF event. These requirements cannot be met by the CSV at its second maximum peak intensity, but the CSV at this stage plays an indispensible role for the formation of the HRF event to make its intensity and rainfall amount larger than those HRF events without this relay intensification. The development of an HRF event through multiple interactions of CSVs with sequential cold surge flows may pose difficulties to numerically simulate/predict the occurrence of these HRF events over the cold-season rainfall centers around the South China Sea.

The South China Sea Arbitration: Bindingness, Finality, and Compliance with UNCLOS Dispute Settlement Decisions

2017 ◽  
Vol 8 (1) ◽  
pp. 36-50
Author(s):  
Hao Duy PHAN ◽  
Lan Ngoc NGUYEN
Keyword(s):  
South China Sea ◽  
South China ◽  
Dispute Settlement ◽  
The Philippines ◽  
The South China Sea ◽  
The South ◽  
China Sea ◽  
Binding Force ◽  
State Compliance ◽  
Dispute Settlement Mechanisms

AbstractOn 12 July 2016, the Tribunal in theSouth China Seaarbitration issued its final award. China rejected the ruling as “null and void”. The Philippines dismissed it as “a piece of paper” after initially hailing the ruling a “milestone decision”. The reactions of the parties concerned raise important questions about the bindingness, finality, and state compliance with UNCLOS dispute settlement decisions. This paper addresses these questions by dissecting China’s arguments that the award “has no binding force” and by examining the options available for promoting compliance with the award. The paper also considers the broader question of how states generally comply with UNCLOS dispute settlement decisions and evaluates the significance of UNCLOS dispute settlement mechanisms, including theSouth China Seaarbitration, in the absence of external enforcement.

Diurnal Cycle of Coastal Convection in the South China Sea Region and Modulation by the BSISO

2021 ◽  
pp. 1-53
Author(s):  
Weixin Xu ◽  
Steven A. Rutledge ◽  
Kyle Chudler
Keyword(s):  
South China Sea ◽  
South China ◽  
The Philippines ◽  
The South China Sea ◽  
Boreal Summer ◽  
Total Precipitation ◽  
The South ◽  
Low Level ◽  
China Sea ◽  
Diurnal Cycles

AbstractUsing 17-yr spaceborne precipitation radar measurements, this study investigates how diurnal cycles of rainfall and convective characteristics over the South China Sea region are modulated by the Boreal Summer Intraseasonal Oscillation (BSISO). Generally, diurnal cycles change significantly between suppressed and active BSISO periods. Over the Philippines and Indochina, where the low-level monsoon flows impinge on coast lines, diurnal cycles of rainfall and many convective properties are enhanced during suppressed periods. During active periods, diurnal variation of convection is still significant over land but diminishes over water. Also, afternoon peaks of rainfall and MCS populations over land are obviously extended in active periods, mainly through the enhancement of stratiform precipitation. Over Borneo, where the prevailing low-level winds are parallel to coasts, diurnal cycles (both onshore and offshore) are actually stronger during active periods. Radar profiles also demonstrate a pronounced nocturnal offshore propagation of deep convection over western Borneo in active periods. During suppressed periods, coastal afternoon convection over Borneo is reduced, and peak convection occurs over the mountains until the convective suppression is overcome in the late afternoon or evening. A major portion (> 70%) of the total precipitation over Philippines and Indochina during suppressed periods falls from afternoon isolated to medium-sized systems (< 10,000 km2), but more than 70% of the active BSISO rainfall is contributed by nocturnal (after 18 LT) broad precipitation systems (> 10,000 km2). However, offshore total precipitation is dominated by large precipitation systems (> 10,000 km2) regardless of BSISO phases and regions.

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