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Bao Ming - One of the best experts on this subject based on the ideXlab platform.

  • the statistical analysis of the persistent Heavy Rain in the last 50 years over china and their backgrounds on the large scale circulation
    Chinese Journal of Atmospheric Sciences, 2007
    Co-Authors: Bao Ming
    Abstract:

    Based on the daily precipitation datasets at 730 stations in China from 1951 to 2005,two objective methods are adopted to depict the variations and characteristics of the persistent Heavy Rain in the last 50 years over China.One is the definition of the local persistent Heavy Rain,and the other is the definition of the regional persistent Heavy Rain.The local persistent Heavy Rain means that sequential Heavy Rain(the daily precipitation amount exceeds 50 mm) occur at a certain station at least 3 days.The regional persistent Heavy Rain denotes that the extent in which the total precipitation amount exceeds 100 mm during 3 days at certain region achieves the threshold,as such the extent in which the daily precipitation amount exceeds 25 mm in the same region achieves this threshold.According to the first definition,the results show that the local persistent Heavy Rain occurs in South China and to the southern parts of the Yangtze River mostly in the last 50 years,and the maximum instances of the local persistent Heavy Rain occur in June.According to the second definition,the results show that there are four kinds of regional persistent Heavy Rain primarily,namely the Bohai Sea-western Liaoning Province type,the northern meridional type,the southern front type,and tropical depression type in South China.Three types in the regions of the Yangtze River-Huaihe River,the southern parts of the Yangtze River and South China are included in the southern front type.All types of regional Heavy Rain searched from the historical observational data are analyzed using the intercomparison method among these cases of the same type.The seasonal and interannual variations of the regional persistent Heavy Rain are compared and these backgrounds on the large scale circulation of the different types are also studied.

  • Characteristics of the Interdecadal Variations of Heavy Rain over China in the Last 40 Years
    Chinese Journal of Atmospheric Sciences, 2006
    Co-Authors: Bao Ming
    Abstract:

    Serious flooding disasters owing to Heavy Rain occur frequently in summer in China,especially in the middle and lower reaches of the Yangtze River.Previous many studies about Heavy Rain in China have been conducted on the synoptic scale,but few on the climatology.Tao and Ding(1981) studied Heavy Rain in China with the data during 1953-1977 and found there are three zones in which Heavy Rain occurs frequently.Matsmoto and Takahashi(1999) studied Heavy Rain in East Asia and pointed out that a Heavy Rain zone exists from the Yangtze River basin in China to the southern parts of Japan.Recently,Zhai et al.(2005) researched the trend of Heavy Rain in China.The characteristics of the interdecadal variations of Heavy Rain in China are analyzed by using the daily precipitation data at 610 stations in China for the Last 40 years of 1961-2000.The results indicate that Heavy Rain mostly occurs in the middle and lower reaches of the Yangtze River,South China,the central and eastern parts of Sichuan Province,the area between the Yellow River and the Huaihe River and the eastern part of North China in summer.The occurrence frequency of the summertime Heavy Rain has an obvious interdecadal variability,but there are some differences among these areas.More Heavy Rain occurred in the 1980s than 1970s followed by a step-up increase in the 1990s in the middle and lower reaches of the Yangtze River.Whereas the decrease of Heavy Rain in the eastern part of North China has happened since the late 1970s.In the boreal spring and autumn,the interdecadal variations in the southern China are not obvious.Moreover,the analyzed results also show that there is a close relationship between Heavy Rain and flooding disasters in the monsoon region of eastern China,especially,Heavy Rain greatly contributed to flooding disasters in the Yangtze River and Huaihe River valleys in the 1990s.Furthermore,the climatic background of interdecadal variability of the occurring frequency of the summer Heavy Rain is also discussed preliminarily.The interdecadal decrease of Heavy Rain in North China from the late 1970s may be related to the interdecadal variation of SST in the equatorial central and eastern Pacific,and the interdecadal increase of Heavy Rain to the south of the Yangtze River in the 1990s may be associated with the thermal convective activities over the eastern part of the tropical northwestern Pacific.The interdecadal variation of outgoing longwave radiation(OLR) over the eastern part of the tropical northwestern Pacific induces the interdecadal variation of the subtropical anticyclone at the lower layer over the northwestern Pacific,which has an impact on the interdecadal variation of Heavy Rain to the south of the Yangtze River in the 1990s.

A. Genovés - One of the best experts on this subject based on the ideXlab platform.

  • Heavy Rain events in the Western Mediterranean: an atmospheric pattern classification
    Advances in Science and Research, 2008
    Co-Authors: C. Martínez, Joan Campins, A. Jansà, A. Genovés
    Abstract:

    Abstract. Heavy Rain is one of the most important high-impact weather phenomena that occasionally affect Mediterranean areas. The aim of this study is to achieve a classification of atmospheric patterns related to Heavy Rain events in both French and Spanish Mediterranean regions. The classification is made on some atmospheric fields (geopotential at 1000 hPa and at 500 hPa and temperature at 850 hPa) of HIRLAM-INM-0.5° operational analysis, for Heavy Rain events included in the High Impact Weather MEDEX database. It covers a period of roughly 7 and a half years, from January 1997 to May 2004. A Principal Components Analysis was conducted to reduce the number of variables. After that, by means of a Cluster Analysis, the Heavy Rain events are classified into 8 atmospheric patterns. The results show a good relationship between regions affected by Heavy Rain and atmospheric patterns, in the sense that the same atmospheric patterns usually produce Heavy Rain in different regions, and Heavy Rain in different regions is usually due to specific atmospheric patterns.

  • Atmospheric patterns for Heavy Rain events in the Balearic Islands
    Advances in Geosciences, 2007
    Co-Authors: A. Lana, Joan Campins, A. Genovés, A. Jansà
    Abstract:

    The Balearic Islands, as well as other Mediter- ranean regions, are occasionally affected by Heavy Rain events, which can produce numerous damages. This study contributes to improve the understanding of the dynamical mechanisms that produce Heavy Rain events by means of a classification of their related atmospheric patterns. Heavy Rainfall dataset for the Balearic Islands and some gridded atmospheric parameters, derived from the HIRLAM- INM-0.5 analyses, were the data used in this study. Heavy Rain events were recorded at a set of pluviometric stations along the Balearics for a period of 9 years, from June 1995 to May 2004. The 1000 hPa and 500 hPa geopotential heights (hereafter 1000 and 500), as well as the 850 hPa temperature (T850) were the fields utilized in the classification. By means of a principal components analysis (PCA) the number of variables was reduced. The cluster analysis (CA) was then applied on those new variables and eight atmo- spheric patterns were finally obtained. Most of the patterns showed a strong relationship between Heavy Rain events and cyclones.

  • Western Mediterranean cyclones and Heavy Rain. Part 2: Statistical approach
    Meteorological Applications, 2001
    Co-Authors: A. Jansà, Joan Campins, A. Genovés, M Angeles Picornell, Ricardo Riosalido, Olinda Carretero
    Abstract:

    This is the second part (statistical approach) of a work concerning the relationship between Heavy Rain and cyclonic centres in the western Mediterranean. Using a statistical approach we seek to verify the indirect role of the cyclone centres in locating, triggering or focusing Heavy Rain: a cyclonic centre –even if neither strong nor deep –may contribute to the low-level flow organisation and so to the creation or intensification of a low-level warm and wet current that can feed and sustain convective Rain in favourable environmental conditions. The foundation for the statistical approach is several Several databases maintained and updated by the Spanish Institute of Meteorology (INM). These databases of cyclonic centres, Heavy Rain and strong wind events, and mesoscale convective systems (MCSs), all covering the western Mediterranean or part thereof, can be cross-referenced by looking for simultaneity between Heavy Rain events (or MCSs) and cyclone centres in the vicinity. We have found that in most of the Heavy Rain events (around 90%) there is a cyclonic centre in the vicinity, usually located so that its presence favours the creation or intensification of a feeding flow of Mediterranean air towards the area affected by Heavy Rain. The same occurs with the MCSs. Copyright © 2001 Royal Meteorological Society

  • western mediterranean cyclones and Heavy Rain part 1 numerical experiment concerning the piedmont flood case
    Meteorological Applications, 2000
    Co-Authors: A Jansa, A. Genovés, Jose Antonio Garciamoya
    Abstract:

    Heavy Rain events constitute a major operational problem in the Mediterranean area. The present work tries to contribute to a better understanding of this problem by considering the possible indirect influence of surface depressions in the triggering and location of the Heavy Rain. The idea is that any surface low contributes to the organisation of the low-level flow. This then affects the creation/intensification of a low-level feeding current of warm and wet air that can sustain Heavy Rain if there is convective instability. Two approaches have been used: (a) a numerical and synoptic approach, Part 1, and (b) a statistical approach, Part 2. In Part 1, the differences between a control run and a numerical experiment without the Iberian mountains for the ‘MAP Piedmont flood event’ are discussed. Among other effects, the Iberian orography seems to intensify a secondary low near Liguria as well as increase the mixing ratio convergence and the Rainfall intensity near it. A few other cases of Heavy Rain are also briefly reviewed in order to identify the presence of a Mediterranean depression in the vicinity.

A. Jansà - One of the best experts on this subject based on the ideXlab platform.

  • Heavy Rain events in the Western Mediterranean: an atmospheric pattern classification
    Advances in Science and Research, 2008
    Co-Authors: C. Martínez, Joan Campins, A. Jansà, A. Genovés
    Abstract:

    Abstract. Heavy Rain is one of the most important high-impact weather phenomena that occasionally affect Mediterranean areas. The aim of this study is to achieve a classification of atmospheric patterns related to Heavy Rain events in both French and Spanish Mediterranean regions. The classification is made on some atmospheric fields (geopotential at 1000 hPa and at 500 hPa and temperature at 850 hPa) of HIRLAM-INM-0.5° operational analysis, for Heavy Rain events included in the High Impact Weather MEDEX database. It covers a period of roughly 7 and a half years, from January 1997 to May 2004. A Principal Components Analysis was conducted to reduce the number of variables. After that, by means of a Cluster Analysis, the Heavy Rain events are classified into 8 atmospheric patterns. The results show a good relationship between regions affected by Heavy Rain and atmospheric patterns, in the sense that the same atmospheric patterns usually produce Heavy Rain in different regions, and Heavy Rain in different regions is usually due to specific atmospheric patterns.

  • Atmospheric patterns for Heavy Rain events in the Balearic Islands
    Advances in Geosciences, 2007
    Co-Authors: A. Lana, Joan Campins, A. Genovés, A. Jansà
    Abstract:

    The Balearic Islands, as well as other Mediter- ranean regions, are occasionally affected by Heavy Rain events, which can produce numerous damages. This study contributes to improve the understanding of the dynamical mechanisms that produce Heavy Rain events by means of a classification of their related atmospheric patterns. Heavy Rainfall dataset for the Balearic Islands and some gridded atmospheric parameters, derived from the HIRLAM- INM-0.5 analyses, were the data used in this study. Heavy Rain events were recorded at a set of pluviometric stations along the Balearics for a period of 9 years, from June 1995 to May 2004. The 1000 hPa and 500 hPa geopotential heights (hereafter 1000 and 500), as well as the 850 hPa temperature (T850) were the fields utilized in the classification. By means of a principal components analysis (PCA) the number of variables was reduced. The cluster analysis (CA) was then applied on those new variables and eight atmo- spheric patterns were finally obtained. Most of the patterns showed a strong relationship between Heavy Rain events and cyclones.

  • Western Mediterranean cyclones and Heavy Rain. Part 2: Statistical approach
    Meteorological Applications, 2001
    Co-Authors: A. Jansà, Joan Campins, A. Genovés, M Angeles Picornell, Ricardo Riosalido, Olinda Carretero
    Abstract:

    This is the second part (statistical approach) of a work concerning the relationship between Heavy Rain and cyclonic centres in the western Mediterranean. Using a statistical approach we seek to verify the indirect role of the cyclone centres in locating, triggering or focusing Heavy Rain: a cyclonic centre –even if neither strong nor deep –may contribute to the low-level flow organisation and so to the creation or intensification of a low-level warm and wet current that can feed and sustain convective Rain in favourable environmental conditions. The foundation for the statistical approach is several Several databases maintained and updated by the Spanish Institute of Meteorology (INM). These databases of cyclonic centres, Heavy Rain and strong wind events, and mesoscale convective systems (MCSs), all covering the western Mediterranean or part thereof, can be cross-referenced by looking for simultaneity between Heavy Rain events (or MCSs) and cyclone centres in the vicinity. We have found that in most of the Heavy Rain events (around 90%) there is a cyclonic centre in the vicinity, usually located so that its presence favours the creation or intensification of a feeding flow of Mediterranean air towards the area affected by Heavy Rain. The same occurs with the MCSs. Copyright © 2001 Royal Meteorological Society

Zhicai Luo - One of the best experts on this subject based on the ideXlab platform.

  • evaluating imerg v04 final run for monitoring three Heavy Rain events over mainland china in 2016
    IEEE Geoscience and Remote Sensing Letters, 2018
    Co-Authors: C K Shum, Zhicai Luo
    Abstract:

    Predicting and monitoring the spatiotemporal characteristics of Heavy Rain events are important to hazard preparedness, mitigation efforts, and local water resource management. Using three data sets, namely, the daily Rain product from the Integrated Multi-satellitE Retrievals for Global Precipitation Measurement (IMERG) version 04 Final Run, the daily output from European Centre for Medium-Range Weather Forecasts reanalysis data Interim version (ERA-Interim), and the high-quality gauge-satellite merged precipitation product, the spatiotemporal patterns of three Heavy Rain events are investigated for the first time over China in 2016, with the objective of assessing the capability of IMERG product for monitoring Heavy Rain events. It is found that the daily IMERG Final Run can better capture the spatial and temporal characteristics of Heavy Rain compared with that from ERA-Interim, but it significantly overestimates the amounts of the heaviest Rainfalls by 11%–85% over the example regions. The comparison of regional averaged precipitation demonstrates that time series of precipitation retrieved by the IMERG algorithm agree well with that from gauge-satellite merged data set, with differences less than 10 mm on most days over each region. The statistic metrics demonstrate that the IMERG Final Run has a strong potential for detecting Heavy Rain events but with a relatively large error. This letter may provide useful feedback and insights for further improving the precipitation retrieving algorithm and the application of such data sets.

Joan Campins - One of the best experts on this subject based on the ideXlab platform.

  • Heavy Rain events in the Western Mediterranean: an atmospheric pattern classification
    Advances in Science and Research, 2008
    Co-Authors: C. Martínez, Joan Campins, A. Jansà, A. Genovés
    Abstract:

    Abstract. Heavy Rain is one of the most important high-impact weather phenomena that occasionally affect Mediterranean areas. The aim of this study is to achieve a classification of atmospheric patterns related to Heavy Rain events in both French and Spanish Mediterranean regions. The classification is made on some atmospheric fields (geopotential at 1000 hPa and at 500 hPa and temperature at 850 hPa) of HIRLAM-INM-0.5° operational analysis, for Heavy Rain events included in the High Impact Weather MEDEX database. It covers a period of roughly 7 and a half years, from January 1997 to May 2004. A Principal Components Analysis was conducted to reduce the number of variables. After that, by means of a Cluster Analysis, the Heavy Rain events are classified into 8 atmospheric patterns. The results show a good relationship between regions affected by Heavy Rain and atmospheric patterns, in the sense that the same atmospheric patterns usually produce Heavy Rain in different regions, and Heavy Rain in different regions is usually due to specific atmospheric patterns.

  • Atmospheric patterns for Heavy Rain events in the Balearic Islands
    Advances in Geosciences, 2007
    Co-Authors: A. Lana, Joan Campins, A. Genovés, A. Jansà
    Abstract:

    The Balearic Islands, as well as other Mediter- ranean regions, are occasionally affected by Heavy Rain events, which can produce numerous damages. This study contributes to improve the understanding of the dynamical mechanisms that produce Heavy Rain events by means of a classification of their related atmospheric patterns. Heavy Rainfall dataset for the Balearic Islands and some gridded atmospheric parameters, derived from the HIRLAM- INM-0.5 analyses, were the data used in this study. Heavy Rain events were recorded at a set of pluviometric stations along the Balearics for a period of 9 years, from June 1995 to May 2004. The 1000 hPa and 500 hPa geopotential heights (hereafter 1000 and 500), as well as the 850 hPa temperature (T850) were the fields utilized in the classification. By means of a principal components analysis (PCA) the number of variables was reduced. The cluster analysis (CA) was then applied on those new variables and eight atmo- spheric patterns were finally obtained. Most of the patterns showed a strong relationship between Heavy Rain events and cyclones.

  • Western Mediterranean cyclones and Heavy Rain. Part 2: Statistical approach
    Meteorological Applications, 2001
    Co-Authors: A. Jansà, Joan Campins, A. Genovés, M Angeles Picornell, Ricardo Riosalido, Olinda Carretero
    Abstract:

    This is the second part (statistical approach) of a work concerning the relationship between Heavy Rain and cyclonic centres in the western Mediterranean. Using a statistical approach we seek to verify the indirect role of the cyclone centres in locating, triggering or focusing Heavy Rain: a cyclonic centre –even if neither strong nor deep –may contribute to the low-level flow organisation and so to the creation or intensification of a low-level warm and wet current that can feed and sustain convective Rain in favourable environmental conditions. The foundation for the statistical approach is several Several databases maintained and updated by the Spanish Institute of Meteorology (INM). These databases of cyclonic centres, Heavy Rain and strong wind events, and mesoscale convective systems (MCSs), all covering the western Mediterranean or part thereof, can be cross-referenced by looking for simultaneity between Heavy Rain events (or MCSs) and cyclone centres in the vicinity. We have found that in most of the Heavy Rain events (around 90%) there is a cyclonic centre in the vicinity, usually located so that its presence favours the creation or intensification of a feeding flow of Mediterranean air towards the area affected by Heavy Rain. The same occurs with the MCSs. Copyright © 2001 Royal Meteorological Society