Climatological characteristics of fronts in the western North Pacific based on surface weather charts

Composite front climatology in the western North Pacific is determined using a newly developed 1.0° gridded data set. Here we propose a research strategy for determining the spatiotemporal distribution of fronts using weather chart images published by the Japan Meteorological Agency, one of the major data providers in the region. A preliminarily investigation of the internal data characteristics for the period of 2000–2010 is undertaken, and the final 4 years of data are used for an analysis of front climatology to avoid the effect of any spurious trends. This enables in‐depth analyses to be conducted, which have not previously been possible in the region, including the composites of cross‐sectional patterns for the thermal fields and precipitation near fronts, front length seasonality, and the significance of the thermal gradient near the fronts, in addition to determining the frontal frequency and spatial distribution of frontal precipitation. Pixel‐wise analysis reveals that 56% of the local precipitation maximum is located on the warm side of a cold front caused by less tilted upward motion on the warm side, with the intrusion of the upper level cold dry air into the warm side. This new data set also enables a further analysis of the occluded fronts, which are not correctly distinguished in the existing objective detection method.

[1]  V. Sinclair.  A 6-yr Climatology of Fronts Affecting Helsinki, Finland, and Their Boundary Layer Structure , 2013 .

[2]  N. Nicholls,et al.  Relating global precipitation to atmospheric fronts , 2012 .

[3]  Ian Simmonds,et al.  Identification and Climatology of Southern Hemisphere Mobile Fronts in a Modern Reanalysis , 2012 .

[4]  Neil F Laird,et al.  Surface Fronts, Troughs, and Baroclinic Zones in the Great Lakes Region , 2011 .

[5]  Michael J. Reeder,et al.  A global climatology of atmospheric fronts , 2011 .

[6]  Michael Sprenger,et al.  Detection and climatology of fronts in a high‐resolution model reanalysis over the Alps , 2009 .

[7]  S. Kobayashi,et al.  The JRA-25 Reanalysis , 2007 .

[8]  Misako Kachi,et al.  Global Precipitation Map Using Satellite-Borne Microwave Radiometers by the GSMaP Project: Production and Validation , 2006, IEEE Transactions on Geoscience and Remote Sensing.

[9]  Phil Dominy.  Creating the daily analysis charts for the Weather log , 2006 .

[10]  F. Sanders.  Real Front or Baroclinic Trough , 2005 .

[11]  Eric G. Hoffman,et al.  A Climatology of Surface Baroclinic Zones , 2002 .

[12]  Donald W. McCann,et al.  Problems and solutions for drawing fronts objectively , 2001 .

[13]  J. Susskind,et al.  Global Precipitation at One-Degree Daily Resolution from Multisatellite Observations , 2001 .

[14]  T. Hewson.  Objective fronts , 1998 .

[15]  P. Hobbs,et al.  Structure and Evolution of Winter Cyclones in the Central United States and Their Effects on the Distribution of Precipitation. Part III: The Development of a Squall Line Associated with Weak Cold Frontogenesis Aloft , 1995 .

[16]  K. Ninomiya,et al.  Multi-scale Features of Baiu, the Summer Monsoon over Japan and the East Asia , 1992 .

[17]  M. Shapiro.  Meteorological Tower Measurements of a Surface Cold Front , 1984 .

[18]  L. H. Horn,et al.  Northern Hemisphere extratropical cyclone activity for four mid‐season months , 1984 .

[19]  K. Browning,et al.  A Simple Model for the Synoptic Analysis of Cold Fronts , 1982 .

[20]  H. Arakawa,et al.  Prefrontal rain bands located in the warm sector of subtropical cyclones over the ocean , 1968 .

[21]  G. Lackmann.  Midlatitude Synoptic Meteorology , 2011 .

[22]  N. Kitabatake.  The role of convective instability and frontogenetic circulation in the torrential rainfall in the Tokai District on 11-12 September 2000. , 2002 .

[23]  F. Fujibe.  Climatology of Mesoscale Warm and Cold Fronts in the Kanto Plain. , 1992 .

[24]  Keith A. Browning,et al.  Organization of Clouds and Precipitation in Extratropical Cyclones , 1990 .

[25]  K. Hoinka.  On fronts in Central Europe , 1985 .

[26]  K. Ninomiya,et al.  Characteristics of Baiu Front as a Predominant Subtropical Front in the Summer Northern Hemisphere , 1984 .

[27]  山川 修治.  A synoptic climatological study of cold fronts and cold frontal precipitation over Japan , 1983 .

[28]  G. Morgan,et al.  Climatology of surface fronts , 1975 .