Case study of the leeside mesolow and mesocyclone in TAMEX

Chung Chieh Wang, George Tai Jen Chen

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

An observational study was performed on a leeside mesolow case that occurred 8 June 1987 during the Taiwan Area Mesoscale Experiment (TAMEX). The case developed as prevailing west-southwest winds strengthened and interacted with the terrain of Taiwan, with a Froude number (Fr = U/Nh) increasing from below 0.3 to over 0.5. A quasi-stationary mesolow formed to the southeast of Taiwan with no closed circulation through most of its 13-h life stages until passage of the Mei-yu front. A stationary and localized mesovortex also formed about 90 km southwest of the low center, but little adjustment was observed between the mesolow and the vortex. Results suggest that airflow at lower levels was blocked and moved around the terrain of the southern Central Mountain Range (CMR). This led to the formation of low-level jets (LLJs) both to the northwest and southeast of Taiwan. The latter branch provided shear vorticity in the background region of the vortex. Air parcels at higher levels, on the other hand, tended to climb over the mountain and caused precipitation on the windward slope, then subsided at the lee side. The subsidence produced the mesolow through adiabatic warming and drying, which was strongest between 1 and 2 km. Latent heat release at the windward side was estimated to contribute a maximum of about 55%-60% of the total warming. Eventually, as the Mei-yu front moved southward along the eastern coast of Taiwan, the mesolow merged with the front and transformed into a migratory mesocyclone along the front.

Original languageEnglish
Pages (from-to)2572-2592
Number of pages21
JournalMonthly Weather Review
Volume130
Issue number11
DOIs
Publication statusPublished - 2002 Nov

Fingerprint

vortex
warming
experiment
Froude number
vorticity
airflow
subsidence
mountain
coast
air
mountain range
drying

ASJC Scopus subject areas

  • Atmospheric Science

Cite this

Case study of the leeside mesolow and mesocyclone in TAMEX. / Wang, Chung Chieh; Chen, George Tai Jen.

In: Monthly Weather Review, Vol. 130, No. 11, 11.2002, p. 2572-2592.

Research output: Contribution to journalArticle

Wang, Chung Chieh ; Chen, George Tai Jen. / Case study of the leeside mesolow and mesocyclone in TAMEX. In: Monthly Weather Review. 2002 ; Vol. 130, No. 11. pp. 2572-2592.
@article{595d7d7aaa9447518d1c11ac76aa4586,
title = "Case study of the leeside mesolow and mesocyclone in TAMEX",
abstract = "An observational study was performed on a leeside mesolow case that occurred 8 June 1987 during the Taiwan Area Mesoscale Experiment (TAMEX). The case developed as prevailing west-southwest winds strengthened and interacted with the terrain of Taiwan, with a Froude number (Fr = U/Nh) increasing from below 0.3 to over 0.5. A quasi-stationary mesolow formed to the southeast of Taiwan with no closed circulation through most of its 13-h life stages until passage of the Mei-yu front. A stationary and localized mesovortex also formed about 90 km southwest of the low center, but little adjustment was observed between the mesolow and the vortex. Results suggest that airflow at lower levels was blocked and moved around the terrain of the southern Central Mountain Range (CMR). This led to the formation of low-level jets (LLJs) both to the northwest and southeast of Taiwan. The latter branch provided shear vorticity in the background region of the vortex. Air parcels at higher levels, on the other hand, tended to climb over the mountain and caused precipitation on the windward slope, then subsided at the lee side. The subsidence produced the mesolow through adiabatic warming and drying, which was strongest between 1 and 2 km. Latent heat release at the windward side was estimated to contribute a maximum of about 55{\%}-60{\%} of the total warming. Eventually, as the Mei-yu front moved southward along the eastern coast of Taiwan, the mesolow merged with the front and transformed into a migratory mesocyclone along the front.",
author = "Wang, {Chung Chieh} and Chen, {George Tai Jen}",
year = "2002",
month = "11",
doi = "10.1175/1520-0493(2002)130<2572:CSOTLM>2.0.CO;2",
language = "English",
volume = "130",
pages = "2572--2592",
journal = "Monthly Weather Review",
issn = "0027-0644",
publisher = "American Meteorological Society",
number = "11",

}

TY - JOUR

T1 - Case study of the leeside mesolow and mesocyclone in TAMEX

AU - Wang, Chung Chieh

AU - Chen, George Tai Jen

PY - 2002/11

Y1 - 2002/11

N2 - An observational study was performed on a leeside mesolow case that occurred 8 June 1987 during the Taiwan Area Mesoscale Experiment (TAMEX). The case developed as prevailing west-southwest winds strengthened and interacted with the terrain of Taiwan, with a Froude number (Fr = U/Nh) increasing from below 0.3 to over 0.5. A quasi-stationary mesolow formed to the southeast of Taiwan with no closed circulation through most of its 13-h life stages until passage of the Mei-yu front. A stationary and localized mesovortex also formed about 90 km southwest of the low center, but little adjustment was observed between the mesolow and the vortex. Results suggest that airflow at lower levels was blocked and moved around the terrain of the southern Central Mountain Range (CMR). This led to the formation of low-level jets (LLJs) both to the northwest and southeast of Taiwan. The latter branch provided shear vorticity in the background region of the vortex. Air parcels at higher levels, on the other hand, tended to climb over the mountain and caused precipitation on the windward slope, then subsided at the lee side. The subsidence produced the mesolow through adiabatic warming and drying, which was strongest between 1 and 2 km. Latent heat release at the windward side was estimated to contribute a maximum of about 55%-60% of the total warming. Eventually, as the Mei-yu front moved southward along the eastern coast of Taiwan, the mesolow merged with the front and transformed into a migratory mesocyclone along the front.

AB - An observational study was performed on a leeside mesolow case that occurred 8 June 1987 during the Taiwan Area Mesoscale Experiment (TAMEX). The case developed as prevailing west-southwest winds strengthened and interacted with the terrain of Taiwan, with a Froude number (Fr = U/Nh) increasing from below 0.3 to over 0.5. A quasi-stationary mesolow formed to the southeast of Taiwan with no closed circulation through most of its 13-h life stages until passage of the Mei-yu front. A stationary and localized mesovortex also formed about 90 km southwest of the low center, but little adjustment was observed between the mesolow and the vortex. Results suggest that airflow at lower levels was blocked and moved around the terrain of the southern Central Mountain Range (CMR). This led to the formation of low-level jets (LLJs) both to the northwest and southeast of Taiwan. The latter branch provided shear vorticity in the background region of the vortex. Air parcels at higher levels, on the other hand, tended to climb over the mountain and caused precipitation on the windward slope, then subsided at the lee side. The subsidence produced the mesolow through adiabatic warming and drying, which was strongest between 1 and 2 km. Latent heat release at the windward side was estimated to contribute a maximum of about 55%-60% of the total warming. Eventually, as the Mei-yu front moved southward along the eastern coast of Taiwan, the mesolow merged with the front and transformed into a migratory mesocyclone along the front.

UR - http://www.scopus.com/inward/record.url?scp=0036853593&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0036853593&partnerID=8YFLogxK

U2 - 10.1175/1520-0493(2002)130<2572:CSOTLM>2.0.CO;2

DO - 10.1175/1520-0493(2002)130<2572:CSOTLM>2.0.CO;2

M3 - Article

AN - SCOPUS:0036853593

VL - 130

SP - 2572

EP - 2592

JO - Monthly Weather Review

JF - Monthly Weather Review

SN - 0027-0644

IS - 11

ER -