Characteristics and Mechanisms of Low-Level Jets in the Yangtze River Delta of China

A dataset obtained using a wind-profile radar located at the Yangtze River Delta in China (N, E) in 2009 was used to investigate the characteristics and evolution of low-level jets (LLJs) along the east China coast. The study investigated the daily and seasonal structures of LLJs as well as several...

Full description

Bibliographic Details
Published in:Boundary-Layer Meteorology
Main Authors: Wei, W., Wu, B. G., Ye, X. X., Wang, H. X., Zhang, H. S.
Other Authors: Zhang, HS (reprint author), Peking Univ, Sch Phys, Dept Atmospher & Ocean Sci, Lab Climate & Ocean Atmosphere Studies, Beijing 100871, Peoples R China., Peking Univ, Sch Phys, Dept Atmospher & Ocean Sci, Lab Climate & Ocean Atmosphere Studies, Beijing 100871, Peoples R China., Tianjin Meteorol Bur, Tianjin 300074, Peoples R China., CAAC, Ningxia Subbur Northwest Air Traff Management Bur, Ningxia 750009, Peoples R China.
Format: Journal/Newspaper
Language:English
Published: boundary layer meteorology 2013
Subjects:
Coastal jet
Hilbert-Huang transform
Land-sea temperature contrasts
Low-level jet
South-west Jet
Yangtze River Delta of China
ATMOSPHERIC BOUNDARY-LAYER
OCEAN DYNAMICS EXPERIMENT
SOUTHERN GREAT-PLAINS
INERTIAL OSCILLATIONS
CALIFORNIA COAST
WARM-SEASON
HILBERT SPECTRUM
WEDDELL SEA
CLIMATOLOGY
INSTABILITY
Weddell
Weddell Sea
Online Access:https://hdl.handle.net/20.500.11897/148193
https://doi.org/10.1007/s10546-013-9852-8
Description
Summary:A dataset obtained using a wind-profile radar located at the Yangtze River Delta in China (N, E) in 2009 was used to investigate the characteristics and evolution of low-level jets (LLJs) along the east China coast. The study investigated the daily and seasonal structures of LLJs as well as several possible causes. A total of 1,407 1-h LLJ periods were detected based on an adaptive definition that enabled determination of four LLJ categories. The majority (77 %) of LLJs were found to have speeds 14.0 m s (maximum of 34.6 m s and occur at an average altitude below 600 m (76 % of the observed LLJs). The dominant direction of the LLJs was from the south-south-west, which accounted for nearly 32 %, with the second most common wind direction ranging from to , albeit with a number of stronger LLJs from the west-south-west. A comparison of LLJs and South-west Jets revealed that the frequencies of occurrence in summer are totally different. Results also revealed that in spring and summer, most LLJs originate from the south-south-west, whereas in autumn and winter, north-east is the dominant direction of origin. The peak heights of LLJs tended to be higher in winter than in other seasons. The horizontal wind speed and peak height of the LLJs displayed pronounced diurnal cycles. The Hilbert-Huang transform technique was applied to demonstrate that the intrinsic mode functions with a cycle of nearly 23 h at levels below 800 m, and the instantaneous amplitudes of inertial events (0.0417-0.0476 h frequencies) have large values at 300-600 m. The variations in the occurrences of LLJs suggested connections between the formation mechanisms of LLJs and the South-west Jet stream, steady occupation of synoptic-scale pressure system, and land-sea temperature contrasts. http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000327208300004&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701 Meteorology & Atmospheric Sciences SCI(E) EI 5 ARTICLE 3 403-424 149

Similar Items