Anagnostou E. N., C. A. Morales, and T. Dinku, 2001: The use of TRMM precipitation radar observations in determining ground radar calibration biases. J. Atmos. Oceanic Technol., 18( 4), 616- 628.10.1175/1520-0426(2001)0182.0.CO;2bc7a050e5b56c0bf1a55a94ed5607c8ahttp%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2001JAtOT..18..616Ahttp://adsabs.harvard.edu/abs/2001JAtOT..18..616ASince the successful launch of the Tropical Rainfall Measuring Mission (TRMM) satellite, measurements of a wide variety of precipitating systems have been obtained with unprecedented detail from the first space-based radar [precipitation radar (PR)]. In this research, a methodology is developed that matches coincident PR and ground-based volume scanning weather radar observations in a common earth parallel three-dimensional Cartesian grid. The data matching is performed in a way that minimizes uncertainties associated with the type of weather seen by the radars, grid resolution, and differences in radar sensitivities, sampling volumes, viewing angles, and radar frequencies. The authors present comparisons of reflectivity observations from the PR and several U.S. weather surveillance Doppler radars (WSR-88D) as well as research radars from the TRMM field campaigns in Kwajalein Atoll and the Large Biosphere Atmospheric (LBA) Experiment. Correlation values above 0.8 are determined between PR and ground radar matched data for levels above the zero isotherm. The reflectivity difference statistics derived from the matched data reveal radar systems with systematic differences ranging from +2 to 7 dB. The authors argue that the main candidate for systematic differences exceeding 1 to 1.5 dB is the ground radar system calibration bias. To verify this argument, the authors used PR comparisons against well-calibrated ground-based systems, which showed systematic differences consistently less than 1.5 dB. Temporal analysis of the PR versus ground radar systematic differences reveals radar sites with up to 4.5-dB bias changes within periods of two to six months. Similar evaluation of the PR systematic difference against stable ground radar systems shows bias fluctuations of less than 0.8 dB. It is also shown that bias adjustment derived from the methodology can have significant impact on the hydrologic applications of ground-based radar measurements. The proposed scheme can be a useful tool for the systematic monitoring of ground radar biases and the studying of its effect. |
Bolen S. M., V. Chandrasekar, 2000: Quantitative cross validation of space-based and ground-based radar observations. J. Appl. Meteor., 39, 2071- 2079.10.1175/1520-0450(2001)0402.0.CO;2fc0a353f1d5833eee28b45e1431e0003http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2000JApMe..39.2071Bhttp://adsabs.harvard.edu/abs/2000JApMe..39.2071BAbstract Simultaneous comparison of data collected from the Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR), and the S-band polarimetric radar, operated by the National Center for Atmospheric Research, is made to cross validate the calibration of the PR instrument and to quantify the effects of precipitation attenuation on PR measurements. Data collected during the Texas and Florida Underflights experiment were used in the cross validation. Quantitatively comparing radar reflectivities from two separate platforms that have widely different view angles, beamwidths, and frequencies is a challenging task. Nevertheless, it is extremely important for cross validation. An analysis procedure to implement such cross validation is presented. Theoretical simulation of S-band and Ku-band reflectivities of the rain medium is also presented to characterize the theoretical difference in reflectivities between S band and Ku band in the absence of attenuation. Analysis indicates that, when the attenua... |
Chen G. T. J., H. C. Chou, 1993: General characteristics of squall lines observed in TAMEX. Mon. Wea. Rev., 121( 3), 726- 733.10.1175/1520-0493(1993)1212.0.CO;291004ce07072e17ddc1197c31da273aahttp%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F1993MWRv..121..726Chttp://adsabs.harvard.edu/abs/1993MWRv..121..726CSix cases of prefrontal squall lines were observed over the Taiwan Strait and western Taiwan during the 1987 Taiwan Area Mesoscale Experiment (TAMEX). The mean propagation speed was 10 m s, and the mean life span was 11.4 h for the six squall lines. All the lines occurred ahead of the Mei-Yu front and moved away from the front with time. The mean environmental conditions associated with the squall lines were analyzed by compositing the six cases. The environmental conditions observed during the TAMEX squall lines were found with characteristics between tropical and midlatitude squall lines. The steering level was near 7 km during the mature stage. A low-level jet at 3–4 km was present, with strong vertical shear in the presquall environment below 700 hPa. The squall lines were oriented 45° to the shear in the 1–3-km layer, like midlatitude cases. The CAPE, however, is similar to the tropical squall lines. The inflow ahead of the squall lines was deeper and stronger below 400 hPa, and the CAPE was higher during the mature stage as compared to the intensifying stage. The squall-line collapse is correlated with decreasing CAPE and low-level inflow ahead of the lines. |
Cifelli R., S. W. Nesbitt, S. A. Rutledge, W. A. Petersen, and S. Yuter, 2007: Radar characteristics of precipitation features in the EPIC and TEPPS regions of the east Pacific. Mon. Wea. Rev., 135( 4), 1576- 1595.e928c34f60d6225daef1eff3f63444ffhttp%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D2007MWRv..135.1576C%26db_key%3DPHY%26link_type%3DEJOURNALhttp://xueshu.baidu.com/s?wd=paperuri%3A%2870e74cec79f453efeecbe789f3e7daca%29&filter=sc_long_sign&tn=SE_xueshusource_2kduw22v&sc_vurl=http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D2007MWRv..135.1576C%26db_key%3DPHY%26link_type%3DEJOURNAL&ie=utf-8&sc_us=14816802824240973626 |
Dee, D. P., Coauthors, 2011: The ERA-Interim reanalysis: Configuration and performance of the data assimilation system. Quart. J. Roy. Meteor. Soc., 137( 656), 553- 597.10.1002/qj.8285e49541e9e977f77d4b4487298c60f84http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1002%2Fqj.828%2Fpdfhttp://onlinelibrary.wiley.com/doi/10.1002/qj.828/pdfABSTRACT ERA-Interim is the latest global atmospheric reanalysis produced by the European Centre for Medium-Range Weather Forecasts (ECMWF). The ERA-Interim project was conducted in part to prepare for a new atmospheric reanalysis to replace ERA-40, which will extend back to the early part of the twentieth century. This article describes the forecast model, data assimilation method, and input datasets used to produce ERA-Interim, and discusses the performance of the system. Special emphasis is placed on various difficulties encountered in the production of ERA-40, including the representation of the hydrological cycle, the quality of the stratospheric circulation, and the consistency in time of the reanalysed fields. We provide evidence for substantial improvements in each of these aspects. We also identify areas where further work is needed and describe opportunities and objectives for future reanalysis projects at ECMWF. Copyright 2011 Royal Meteorological Society |
Ding Y. H., 1992: Summer monsoon rainfalls in China. J. Meteor. Soc.Japan, 70( 1B), 373- 396.cce449cfd51cb2024f70cfc3af8e54echttp%3A%2F%2Fci.nii.ac.jp%2Fnaid%2F10013125892%2Fhttp://ci.nii.ac.jp/naid/10013125892/Summer monsoon rainfalls in China DING Y.-H. J. Meteor. Soc. Japan 70, 337-396, 1992 |
Ding Y. H., J. C. L. Chan, 2005: The East Asian summer monsoon: An overview. Meteor. Atmos. Phys., 89( 1-4), 117- 142.10.1007/s00703-005-0125-z4fc03ef7f52d18a6b06360a88b350048http%3A%2F%2Flink.springer.com%2F10.1007%2Fs00703-005-0125-zhttp://link.springer.com/10.1007/s00703-005-0125-zThe present paper provides an overview of major problems of the East Asian summer monsoon. The summer monsoon system over East Asia (including the South China Sea (SCS)) cannot be just thought of as t |
Funk A., C. Schumacher, and J. Awaka, 2013: Analysis of rain classifications over the tropics by version 7 of the TRMM PR 2A23 algorithm. J. Meteor. Soc.Japan, 91( 3), 257- 272.10.2151/jmsj.2013-302af1a06a4d44880024cecee591d6605d9http%3A%2F%2Fci.nii.ac.jp%2Fnaid%2F40019673826http://ci.nii.ac.jp/naid/40019673826ABSTRACT |
Geerts B., 1998: Mesoscale convective systems in the southeast United States during 1994-95: A survey. Wea.Forecasting, 13( 3), 860- 869.10.1175/1520-0434(1998)0132.0.CO;2ea1237b01e530c6e66c2e63faffe6382http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F1998WtFor..13..860Ghttp://adsabs.harvard.edu/abs/1998WtFor..13..860GA preliminary survey of mesoscale convective systems (MCSs) in the southeastern United States is presented. MCSs are identified and characterized by means of high-resolution, digital, composite radar reflectivity data. Surveys of this kind are needed to give forecasters better guidance in their real-time assessment of MCS evolution, severe weather potential, and quantitative precipitation. The average lifetime and maximum length of the nearly 400 MCSs included in this survey are 9 h and 350 km, respectively. MCSs are more common in the summer months, when small and short-lived MCSs dominate. In winter larger and longer-lived systems occur more frequently. Because cold-season MCSs, which are about half as numerous as warm-season MCSs, are larger in size and duration, the MCS probability at any location is about constant throughout the year. In summer MCSs occur more commonly in the afternoon, approximately in phase with thunderstorm activity, but the amplitude of the diurnal cycle is small compared to that of observed thunderstorms. Some characteristic echo patterns are discussed. |
Heymsfield G. M., B. Geerts, and L. Tian, 2000: TRMM precipitation radar reflectivity profiles as compared with high-resolution airborne and ground-based radar measurements. J. Appl. Meteor., 39( 12), 2080- 2102.1c89b2ab1209424ca8044105eb53de96http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D2000JApMe..39.2080H%26db_key%3DPHY%26link_type%3DABSTRACThttp://xueshu.baidu.com/s?wd=paperuri%3A%28f91c2dca4f9da848969514aedec2fd4b%29&filter=sc_long_sign&tn=SE_xueshusource_2kduw22v&sc_vurl=http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D2000JApMe..39.2080H%26db_key%3DPHY%26link_type%3DABSTRACT&ie=utf-8&sc_us=15867978489297708425 |
Hou, A. Y., Coauthors, 2014: The global precipitation measurement mission. Bull. Amer. Meteor. Soc., 95( 5), 701- 722.10.1175/BAMS-D-13-00164.176afe45ee9ecd5ec8fa02134e8210871http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2014BAMS...95..701Hhttp://adsabs.harvard.edu/abs/2014BAMS...95..701HABSTRACT The GPM mission is specifically designed to unify and advance precipitation measurements from a constellation of research and operational microwave sensors. NASA and JAXA have successfully deployed the GPM Core Observatory on February 28, 2014, building upon the success of TRMM launched by NASA of the US and JAXA of Japan in 1997. The observatory carries the first spaceborne dual-frequency phased array precipitation radar, the DPR, operating at Ku and Ka bands and a conical-scanning multi-channel microwave imager known as the GMI. This sensor package is an extension of the TRMM instruments, which focused primarily on heavy to moderate rain over tropical and subtropical oceans. The GPM sensors will extend the measurement range attained by TRMM to include light-intensity precipitation and falling snow, which accounts for a significant fraction of precipitation occurrence in the middle and high latitudes. |
Houze R. A., Jr., 1997: Stratiform precipitation in regions of convection: A meteorological paradox? Bull. Amer. Meteor. Soc., 78( 10), 2179- 2196.10.1175/1520-0477(1997)0782.0.CO;26a1490b30b27afa862b1d686025407f6http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F1997BAMS...78.2179Hhttp://adsabs.harvard.edu/abs/1997BAMS...78.2179HFocuses on stratiform precipitation. Impact of such precipitation on tropical rainfall levels; Definition of the concept of convection; Results of radar observations in tropical field experiments. |
Houze R. A., Jr., M. I. Biggerstaff, S. A. Rutledge, and B. F. Smull, 1989: Interpretation of Doppler weather radar displays of midlatitude mesoscale convective systems. Bull. Amer. Meteor. Soc., 70( 6), 608- 619.10.1175/1520-0477(1989)0702.0.CO;22d496d549e12ca1aa2c4236f35492b71http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F1989BAMS...70..608Hhttp://adsabs.harvard.edu/abs/1989BAMS...70..608HThe utility of color displays of Doppler-radar data in revealing real-time kinematic information has been demonstrated in past studies, especially for extratropical cyclones and severe thunderstorms. Such displays can also indicate aspects of the circulation within a certain type of mesoscale convective system-the squall line with trailing "stratiform" rain. Displays from a single Doppler radar collected in two squall-line storms observed during the Oklahoma-Kansas PRE-STORM project conducted in May and June 1985 reveal mesoscale-flow patterns in the stratiform rain region of the squall line, such as front-to-rear storm-relative flow at upper levels, a subsiding storm-relative rear inflow at middle and low levels, and low-level divergent flow associated with strong mesoscale subsidence. "Dual-Doppler" analysis further illustrates these mesoscale-flow features and, in addition, shows the structure of the convective region within the squall line and a mesoscale vortex in the "stratiform" region trailing the line. A refined conceptual model of this type of mesoscale convective system is presented based on previous studies and observations reported here.Recognition of "single-Doppler-radar" patterns of the type described in this paper, together with awareness of the conceptual model, should aid in the identification and interpretation of this type of mesoscale system at future NEXRAD sites. The dual-Doppler results presented here further indicate the utility of multiple-Doppler observations of mesoscale convective systems in the STORM program. |
Houze R. A., Jr., S. Brodzik, C. Schumacher, S. E. Yuter, and C. R. Williams, 2004: Uncertainties in oceanic radar rain maps at Kwajalein and implications for satellite validation. J. Appl. Meteor., 43( 8), 1114- 1132.10.1175/1520-0450(2004)0432.0.CO;26fc7dad779eff20c6daaae27d11905d3http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2004JApMe..43.1114Hhttp://adsabs.harvard.edu/abs/2004JApMe..43.1114HThe Kwajalein, Marshall Islands, Tropical Rainfall Measuring Mission (TRMM) ground validation radar has provided a multiyear three-dimensional radar dataset at an oceanic site. Extensive rain gauge networks are not feasible over the ocean and, hence, are not available to aid in calibrating the radar or determining a conversion from reflectivity to rain rate. This paper describes methods used to ensure the calibration and allow the computation of quantitative rain maps from the radar data without the aid of rain gauges. Calibration adjustments are made by comparison with the TRMM satelliteborne precipitation radar. The additional steps required to convert the calibrated reflectivity to rain maps are the following: correction for the vertical profile of reflectivity below the lowest elevation angle using climatological convective and stratiform reflectivity profiles; conversion of reflectivity (Z) to rain rate (R) with a relationship based on disdrometer data collected at Kwajalein, and a gap-filling estimate. The time series of rain maps computed by these procedures include low, best, and high estimates to frame the estimated overall uncertainty in the radar rain estimation. The greatest uncertainty of the rain maps lies in the calibration of the radar (卤30%). The estimation of the low-altitude vertical profile of reflectivity is also a major uncertainty (卤15%). The Z-R and data-gap uncertainties are relatively minor (卤5% or less). These uncertainties help to prioritize the issues that need to be addressed to improve quantitative rainfall mapping over the ocean and provide useful bounds when comparing radar-derived rain estimates with other remotely sensed measures of oceanic rain (such as from satellite passive microwave sensors). |
Houze R. A., Jr., D. C. Wilton, and B. F. Smull, 2007: Monsoon convection in the Himalayan region as seen by the TRMM Precipitation Radar. Quart. J. Roy. Meteor. Soc., 133( 627), 1389- 1411.10.1002/qj.106028aa5645765e6ed5d8ba5e4acee6346http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1002%2Fqj.106%2Ffullhttp://onlinelibrary.wiley.com/doi/10.1002/qj.106/fullThree-dimensional structure of summer monsoon convection in the Himalayan region and its overall variability are examined by analyzing data trom the Iropical Raintall Measuring Mission (TRMM) Precipitation Radar over the June-September seasons of 2002 and 2003. Statistics are compiled for both convective and stratiform components of the observed radar echoes. Deep intense convective echoes (40 dBZ echo reaching heights >10 km) occur primarily just upstream (south) of and over the lower elevations of the Himalayan barrier, especially in the northwestern concave indentation of the barrier. The deep intense convective echoes are vertically erect, consistent with the relatively weak environmental shear. They sometimes extend above 17 km, indicating that exceptionally strong updraughts loft graupel to high altitudes. Occasionally, scattered isolated deep intense convective echoes occur over the Tibetan Plateau. Wide intense convective echoes (40 dBZ echo >1000 km |
Iguchi T., T. Kozu, R. Meneghini, J. Awaka, and K. Okamoto, 2000: Rain-profiling algorithm for the TRMM precipitation radar. J. Appl. Meteor., 39( 12), 2038- 2052.10.1109/IGARSS.1997.60899503d60344fa2e73a65960735adf1c2c3ahttp%3A%2F%2Fieeexplore.ieee.org%2Fxpl%2FabstractCitations.jsp%3Freload%3Dtrue%26tp%3D%26arnumber%3D608995http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=608995This paper describes the Tropical Rainfall Measuring Mission (TRMM) standard algorithm that estimates the vertical profiles of attenuation-corrected radar reflectivity factor and rainfall rate. In particular, this paper focuses on the critical steps in the algorithm. These steps are attenuation correction, selection of the default drop size distribution model including vertical variations, and correction for the nonuniform beam-filling effect. The attenuation correction is based on a hybrid of the Hitschfeld-Bordan method and a surface reference method. A new algorithm to obtain an optimum weighting function is described. The nonuniform beam-filling problem is analyzed as a two-dimensional problem. The default drop size distribution model is selected according to the criterion that the attenuation estimates derived from the model and the independent estimates from the surface reference with the nonuniform beam-filling correction are consistent for rain over ocean. It is found that the drop size distribution models that are consistent for convective rain over ocean are not consistent over land, indicating a change in the size distributions associated with convective rain over land and ocean, respectively. |
Kawanishi T., Coauthors, 2000: TRMM precipitation radar. Advances in Space Research, 25( 5), 969- 972.10.1109/IGARSS.1993.3223159b128484-58b1-4daa-bdb0-b59ca26df2d4f00d4ab1627a7406c347844f5f9d42a4http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D322315refpaperuri:(1b2ed0c315f7af7b7ccb302b7c256bb1)http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=322315Precipitation Radar (PR) is a key sensor of the Tropical Rainfall Measuring Mission (TRMM) that is a U.S./Japan joint project to measure tropical and sub-tropical rainfall from space. The preliminary design of the PR has been completed and currently an engineering model is being developed. The PR consists of 128 T/R modules to construct an active phased array system at 13.8 GHz, and has the minimum measurable rain rate as low as 0.7 mm/h with a range resolution of 250 m, a horizontal resolution of about 4 km, and a swath width of 215 km. A combined internal and external calibration scheme is also being developed. In the presentation, system design, system parameters and calibration scheme as well as the development status of the PR are outlined |
Kessinger C., S. Ellis, J. V. Andel, J. Yee, and J. Hubbert, 2003: The AP clutter mitigation scheme for the WSR-88D. Preprints, 31st Conference on Radar Meteorology, Seattle, WA, Amer. Meteor. Soc., 526- 529.75e2c497-b62f-4858-83bf-cb60300c6c989259c762c37f1984f50303aec78788a2http%3A%2F%2Fwww.mendeley.com%2Fresearch%2Fap-clutter-mitigation-scheme-wsr-88d%2Frefpaperuri:(ad49b134ae77570dd71ce90b101d25a7)http://www.mendeley.com/research/ap-clutter-mitigation-scheme-wsr-88d/ |
Kozu T., T. Iguchi, 1999: Nonuniform beamfilling correction for spaceborne radar rainfall measurement: implications from TOGA COARE radar data analysis. J. Atmos. Oceanic Technol., 16( 11), 1722- 1735.10.1175/1520-0426(1999)0162.0.CO;200c2d52c4f1e4791febda26010391aadhttp%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F1999JAtOT..16.1722Khttp://adsabs.harvard.edu/abs/1999JAtOT..16.1722KA method is studied to make a nonuniform beamfilling (NUBF) correction for the path-integrated attenuation (PIA) derived from spaceborne radar measurement. The key of this method is to estimate rain-rate variability within a radar field of view from the local statistics of a radar-measurable quantity (〈〉) such as PIA derived from the surface reference technique. Statistical analyses are made on spatial variabilities of the radar-measurable quantities using a shipborne radar dataset over the tropical Pacific obtained during the TOGA COARE field campaign. It is found that there are reasonably good correlations between the coarse-scale variability of 〈〉 and the finescale variability of rain rate, and the regression coefficient (slope) of these two quantities depends somewhat upon rain types. Based on the statistical analyses, the method is tested with a simulation using the same dataset. The test result indicates that this method is effective in reducing bias errors in the estimation of rain-rate statistics. Although it is also effective to make the NUBF correction on an individual instantaneous field-of-view basis, one must account for the variability of local rainfall statistical characteristics that may cause significant errors in the NUBF correction. |
Kummerow C., W. Barnes, T. Kozu, J. Shiue, and J. Simpson, 1998: The tropical rainfall measuring mission (TRMM) sensor package. J. Atmos. Oceanic Technol., 15( 3), 809- 817.10.1175/1520-0426(1998)0152.0.CO;20efc690f-899a-4b57-92ac-fbaf4e83a29502df23a3fe3170d74ba8b7f7319d789chttp%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1002%2F9780471743989.vse10190%2Fpdfrefpaperuri:(dc43a9c9c15bc2be15a9d2bda0c1078f)http://onlinelibrary.wiley.com/doi/10.1002/9780471743989.vse10190/pdfAbstract This note is intended to serve primarily as a reference guide to users wishing to make use of the Tropical Rainfall Measuring Mission data. It covers each of the three primary rainfall instruments: the passive microwave radiometer, the precipitation radar, and the Visible and Infrared Radiometer System on board the spacecraft. Radiometric characteristics, scanning geometry, calibration procedures, and data products are described for each of these three sensors. |
Langston C., J. Zhang, and K. Howard, 2007: Four-dimensional dynamic radar mosaic. J. Atmos. Oceanic Technol., 24, 776- 790.10.1175/JTECH2001.1ad72082d-71ca-4e92-b2fa-915d509e2451f5b831b6d9749f6c569d6026dd003ddfhttp%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2007JAtOT..24..776Lrefpaperuri:(44f51f89672589207001de133d58863b)http://adsabs.harvard.edu/abs/2007JAtOT..24..776LCommunities and many industries are affected by severe weather and have a need for real-time accurate Weather Surveillance Radar-1988 Doppler (WSR-88D) data spanning several regions. To fulfill this need the National Severe Storms Laboratory has developed a Four-Dimensional Dynamic Grid (4DDG) to accurately represent discontinuous radar reflectivity data over a continuous 4D domain. The objective is to create a seamless, rapidly updating radar mosaic that is well suited for use by forecasters in addition to advance radar applications such as qualitative precipitation estimates. Several challenges are associated with creating a 3D radar mosaic given the nature of radar data and the spherical coordinates of radar observations. The 4DDG uses spatial and temporal weighting schemes to overcome these challenges, with the intention of applying minimal smoothing to the radar data. Previous multiple radar mosaics functioned in two or three dimensions using a variety of established weighting schemes. The 4DDG has the advantage of temporal weighting to smooth radar observations over time. Using an exponentially decaying weighting scheme, this paper will examine different weather scenarios and show the effects of temporal smoothing using different time scales. Specifically, case examples of the 4DDG approach involving a rapidly evolving convective event and a slowly developing stratiform weather regime are considered. |
Liao L., R. Meneghini, and T. Iguchi, 2001: Comparisons of rain rate and reflectivity factor derived from the TRMM precipitation radar and the WSR-88D over the Melbourne, Florida, site. J. Atmos. Oceanic Technol., 18( 12), 1959- 1974.10.1175/1520-0426(2001)0182.0.CO;2282bd13fad6adba23ab82776baa82203http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2001JAtOT..18.1959Lhttp://adsabs.harvard.edu/abs/2001JAtOT..18.1959LValidating the results from the spaceborne Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) requires comparisons with well-calibrated ground-based radar measurements. At altitudes near the storm top, where effects of PR signal attenuation are small, the data are used to check the relative calibration accuracy of the radars. Near the surface, where attenuation effects at the PR frequency of 13.8 GHz can be significant, the data provide an assessment of the performance of the PR attenuation correction algorithm. The ground-based data are taken from the Doppler Weather Surveillance (WSR-88D) radar located at Melbourne, Florida. In 1998, 24 overpasses of the TRMM satellite over the Melbourne site occurred during times when significant precipitation was present in the overlap region of the PR and WSR-88D. Resampling the ground-based and spaceborne datasets to a common grid provides a means by which the radar reflectivity factors (dBZ) can be compared at different heights and for different rain types over ocean and land. The results from 1998 show that the dBZ fields derived from the PR data after attenuation correction agree to within about 1 dB of those obtained from the WSR-88D with relatively minor variations (0.3 dB) in this difference with height. Comparisons of rain rates also yield good agreement with the conditional mean rain rate from the PR and WSR-88D of 8.5 and 7.6 mm h[sup -1] , respectively. The agreement improves in the comparison of area-averaged rain rates where the PR and WSR-88D yield values of 1.25 and 1.21 mm h[sup -1] , respectively, with a correlation coefficient for the 24 overpasses of 0.95. |
Liu L. P., Q. Xu, P. F. Zhang, and S. Liu, 2008: Automated detection of contaminated radar image pixels in mountain areas. Adv. Atmos. Sci.,25(5), 778-790, doi: 10.1007/s00376-008-0778-x.10.1007/s00376-008-0778-x4a447e047524dbf03dd73543cda099b7http%3A%2F%2Fwww.cnki.com.cn%2FArticle%2FCJFDTotal-DQJZ200805010.htmhttp://d.wanfangdata.com.cn/Periodical_dqkxjz-e200805008.aspx |
Luo Y. L., Y. J. Wang, H. Y. Wang, Y. J. Zheng, and H. Morrison, 2010: Modeling convective-stratiform precipitation processes on a Mei-Yu front with the Weather Research and Forecasting model: Comparison with observations and sensitivity to cloud microphysics parameterizations. J. Geophys. Res., 115,D18117, doi: 10.1029/2010JD013873. |
Luo Y. L., W. M. Qian, R. H. Zhang, and D.-L. Zhang, 2013a: Gridded hourly precipitation analysis from high-density rain gauge network over the Yangtze-Huai Rivers Basin during the 2007 Mei-Yu season and comparison with CMORPH. J. Hydrometeor., 14( 4), 1243- 1258.10.1175/JHM-D-12-0133.17a5d66dae8c2d5253775347e1369660ahttp%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2013JHyMe..14.1243Lhttp://adsabs.harvard.edu/abs/2013JHyMe..14.1243LNot Available |
Luo Y. L., H. Wang, R. H. Zhang, W. M. Qian, and Z. Z. Luo, 2013b: Comparison of rainfall characteristics and convective properties of monsoon precipitation systems over South China and the Yangtze and Huai River basin. J.Climate, 26( 1), 110- 132.10.1175/JCLI-D-12-00100.17706938239b9c8b56b1e8c89e7ca376dhttp%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2013JCli...26..110Lhttp://adsabs.harvard.edu/abs/2013JCli...26..110LNot Available |
Luo Y. L., Y. Gong, and D.-L. Zhang, 2014: Initiation and organizational modes of an extreme-rain-producing mesoscale convective system along a Mei-Yu Front in East China. Mon. Wea. Rev., 142( 1), 203- 221.10.1175/MWR-D-13-00111.1f7e06671004c87149ca403b878e4ceb8http%3A%2F%2Fwww.researchgate.net%2Fpublication%2F273635799_Initiation_and_organizational_modes_of_an_extreme-rain-producing_mesoscale_convective_system_along_a_Mei-yu_front_in_East_Chinahttp://www.researchgate.net/publication/273635799_Initiation_and_organizational_modes_of_an_extreme-rain-producing_mesoscale_convective_system_along_a_Mei-yu_front_in_East_ChinaAbstract The initiation and organization of a quasi-linear extreme-rain-producing mesoscale convective system (MCS) along a mei-yu front in east China during the midnight-to-morning hours of 8 July 2007 are studied using high-resolution surface observations and radar reflectivity, and a 24-h convection-permitting simulation with the nested grid spacing of 1.11 km. Both the observations and the simulation reveal that the quasi-linear MCS forms through continuous convective initiation and organization into west–east-oriented rainbands with life spans of about 4–10 h, and their subsequent southeastward propagation. Results show that the early convective initiation at the western end of the MCS results from moist southwesterly monsoonal flows ascending cold domes left behind by convective activity that develops during the previous afternoon-to-evening hours, suggesting a possible linkage between the early morning and late afternoon peaks of the mei-yu rainfall. Two scales of convective organization are found during the MCS's development: one is the east- to northeastward “echo training” of convective cells along individual rainbands, and the other is the southeastward “band training” of the rainbands along the quasi-linear MCS. The two organizational modes are similar within the context of “training” of convective elements, but they differ in their spatial scales and movement directions. It is concluded that the repeated convective backbuilding and the subsequent echo training along the same path account for the extreme rainfall production in the present case, whereas the band training is responsible for the longevity of the rainbands and the formation of the quasi-linear MCS. |
Meng Z. Y., Y. J. Zhang, 2012: On the squall lines preceding landfalling tropical cyclones in China. Mon. Wea. Rev., 140( 2), 445- 470.10.1175/MWR-D-10-05080.1e5856cfb21a37eb3650bb3beb5bfbc04http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2012MWRv..140..445Mhttp://adsabs.harvard.edu/abs/2012MWRv..140..445MBased on a 3-yr (2007-09) mosaic of radar reflectivity and conventional surface and synoptic radiosonde observations, the general features of squall lines preceding landfalling tropical cyclones (TCs) (pre-TC) in China are examined and compared with their midlatitude and subtropical counterparts. The results show that about 40%% of landfalling TCs are associated with pre-TC squall lines with high-occurring frequency in August and from late afternoon to midnight. Most pre-TC squall lines form in a broken-line mode with a trailing-stratiform organization. On average, they occur about 600 km from the TC center in the front-right quadrant with a maximum length of 220 km, a maximum radar reflectivity of 57-62 dB Z, a life span of 4 h, and a moving speed of 12.5 m s0903’1. Pre-TC squall lines are generally shorter in lifetime and length than typical midlatitude squall lines. Pre-TC squall lines tend to form in the transition area between the parent TC and subtropical high in a moist environment and with a weaker cold pool than their midlatitude counterparts. The environmental 0-3-km vertical shear is around 10 m s0903’1 and generally normal to the orientation of the squall lines. This weak shear makes pre-TC squall lines in a suboptimal condition according to the Rottuno-Klemp-Weisman (RKW) theory. Convection is likely initiated by low-level mesoscale frontogenesis, convergence, and/or confluence instead of synoptic-scale forcing. The parent TC may contribute to (i) the development of convection by enhancing conditional instability and low-level moisture supply, and (ii) the linear organization of discrete convection through the interaction between the TC and the neighboring environmental system. |
Parker M. D., R. H. Johnson, 2000: Organizational modes of midlatitude mesoscale convective systems. Mon. Wea. Rev., 128( 10), 3413- 3436.10.1175/1520-0493(2001)1292.0.CO;2bced1c47ac08e60d5a835e4d9b512c6dhttp%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2000mwrv..128.3413phttp://adsabs.harvard.edu/abs/2000mwrv..128.3413pThis paper discusses common modes of mesoscale convective organization. Using 2-km national composite reflectivity data, the authors investigated linear mesoscale convective systems (MCSs) that occurred in the central United States during May 1996 and May 1997. Based upon the radar-observed characteristics of 88 linear MCSs, the authors propose a new taxonomy comprising convective lines with trailing (TS), leading (LS), and parallel (PS) stratiform precipitation. While the TS archetype was found to be the dominant mode of linear MCS organization, the LS and PS archetypes composed nearly 40% of the studied population. In this paper, the authors document the characteristics of each linear MCS class and use operational surface and upper air data to describe their different environments. In particular, wind profiler data reveal that the stratiform precipitation arrangement associated with each class was roughly consistent with the advection of hydrometeors implied by the mean middle- and upper-tropospheric storm-relative winds, which were significantly different among the three MCS modes. Case study examples are presented for both the LS and PS classes, which have received relatively little attention to this point. As well, the authors give a general overview of the synoptic-scale meteorology accompanying linear MCSs in this study, which was generally similar to that observed by previous investigators. |
Schumacher C., R. A. Houze Jr., 2000: Comparison of radar data from the TRMM satellite and Kwajalein oceanic validation site. J. Appl. Meteor., 39( 12), 2151- 2164.10.1175/1520-0450(2001)0402.0.CO;28c73f86a87853110183ecd6e8a1ded9fhttp%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2000JApMe..39.2151Shttp://adsabs.harvard.edu/abs/2000JApMe..39.2151SData from the Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) and Kwajalein S-band validation radar (KR) agree well for reflectivity exceeding the sensitivity of the PR threshold (6517 dB). For echoes above this intensity threshold, the products derived from reflectivity, particularly maps of rainfall rate and convective/stratiform classification, compare well, even though slightly different convective–stratiform separation techniques and different reflectivity–rainfall rate () relations are used for the PR and KR. The KR observations indicate the PR misses only 2.3% of near-surface rainfall but 46% of near-surface rain area (≥0 dB) because of its 17-dBthreshold. The PR senses less than 15% of the echo area observed by the KR above 5-km altitude (i.e., above the 0°C level). Thus, the PR highly undersamples weaker echoes associated with stratiform rain near the surface and ice particles aloft but still manages to capture most of the near-surface precipitation accumulation. The temporal sampling of the TRMM PR accurately captures the KR’s overall frequency distribution of reflectivity and its subdivision into convective and stratiform components. However, diurnal and latitudinal variations of precipitation in the vicinity of Kwajalein are not well sampled. |
Schumacher R. S., R. H. Johnson, 2005: Organization and environmental properties of extreme-rain-producing mesoscale convective systems. Mon. Wea. Rev., 133( 4), 961- 976.10.1175/MWR2899.14c08ecd8516791eb2d601faae0173635http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2005mwrv..133..961shttp://adsabs.harvard.edu/abs/2005mwrv..133..961sNot Available |
Schumacher R. S., R. H. Johnson, 2006: Characteristics of U.S. extreme rain events during 1999-2003. Wea.Forecasting, 21( 1), 69- 85.10.1175/WAF900.174d72c6ef3d6306ee7d82094430ce882http%3A%2F%2Fci.nii.ac.jp%2Fnaid%2F30022368284http://ci.nii.ac.jp/naid/30022368284This study examines the characteristics of a large number of extreme rain events over the eastern two-thirds of the United States. Over a 5-yr period, 184 events are identified where the 24-h precipitation total at one or more stations exceeds the 50-yr recurrence amount for that location. Over the entire region of study, these events are most common in July. In the northern United States, extreme rain events are confined almost exclusively to the warm season; in the southern part of the country, these events are distributed more evenly throughout the year. National composite radar reflectivity data are used to classify each event as a mesoscale convective system (MCS), a synoptic system, or a tropical system, and then to classify the MCS and synoptic events into subclassifications based on their organizational structures. This analysis shows that 66% of all the events and 74% of the warm-season events are associated with MCSs; nearly all of the cool-season events are caused by storms with strong synoptic forcing. Similarly, nearly all of the extreme rain events in the northern part of the country are caused by MCSs; synoptic and tropical systems play a larger role in the South and East. MCS-related events are found to most commonly begin at around 1800 local standard time (LST), produce their peak rainfall between 2100 and 2300 LST, and dissipate or move out of the affected area by 0300 LST. |
Simpson J., C. Kummerow, W.-K. Tao, and R. F. Adler, 1996: On the tropical rainfall measuring mission (TRMM). Meteor. Atmos. Phys., 60( 1-3), 19- 36.10.1007/BF01029783e6f8932ee368d4f77ca182de0e0f97ddhttp%3A%2F%2Flink.springer.com%2Farticle%2F10.1007%2FBF01029783http://link.springer.com/article/10.1007/BF01029783Not Available |
Steiner M., R. A. Houze Jr., and S. E. Yuter, 1995: Climatological characterization of three-dimensional storm structure from operational radar and rain gauge data. J. Appl. Meteor., 34( 9), 1978- 2007.2a0fe6e81b00f0e57a87cb413d6fe305http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D1995JApMe..34.1978S%26db_key%3DPHY%26link_type%3DABSTRACThttp://xueshu.baidu.com/s?wd=paperuri%3A%28ef5e0b27981ee31e35a128d59b27ba5e%29&filter=sc_long_sign&tn=SE_xueshusource_2kduw22v&sc_vurl=http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D1995JApMe..34.1978S%26db_key%3DPHY%26link_type%3DABSTRACT&ie=utf-8&sc_us=1476734260661320691 |
Takahashi N., H. Kuroiwa, and T. Kawanishi, 2003: Four-year result of external calibration for Precipitation Radar (PR) of the Tropical Rainfall Measuring Mission (TRMM) satellite. IEEE Transactions on Geoscience and Remote Sensing, 41( 10), 2398- 2403.10.1109/TGRS.2003.8171800b641d0460d210b6fb944c82668bfaa0http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Ficp.jsp%3Farnumber%3D1237421http://ieeexplore.ieee.org/xpls/icp.jsp?arnumber=1237421Not Available |
TRMM PR Team, 2011: Tropical Rainfall Measuring Mission (TRMM) precipitation radar algorithm Instruction Manual for Version 7. JAXA-NASA,170 pp. [Available online at ]http://www.eorc.jaxa.jp/TRMM/documents/PR_algorithm_product_information/pr_manual/PR_Instruction_Manual_V7_L1.pdf. |
Wang H. Y., L. P. Liu, G. L. Wang, W. Zhuang, Z. Q. Zhang, and X. L. Chen, 2009: Development and application of the Doppler weather radar 3-D digital mosaic system. Journal of Applied Meteorological Science, 20( 2), 241- 224. (in Chinese)10.1016/S1874-8651(10)60080-4687fca0d0645fb85d968693849b13e8chttp%3A%2F%2Fen.cnki.com.cn%2FArticle_en%2FCJFDTOTAL-YYQX200902012.htmhttp://en.cnki.com.cn/Article_en/CJFDTOTAL-YYQX200902012.htmToday,most radar sites of the CINRAD have been established,and there is good condition to transmit radar base data to the regional center.To fully utilize the advantage of the Doppler weather radar network,and improve the capability of mesoscale disaster weather early warning,study about weather radar 3-D mosaic has been made in recent years,and the Doppler weather radar 3-D digital mosaic system is developed for the first time in China based on these research results.It introduces the design,system structure,main function modules,data process flow,and corresponding algorithms of the system,analysis software performance,practicality and reliability of the mosaic results,study methods to discriminate two important factors affect the mosaic results.The system includes the following modules: Base data loading,data time matching,data quality controlling,coordinates conversion of single site base data to Cartesian coordinates,reflectivity mosaic for all sites in the region,and the generation of series of derived products.It can provide quality controlled base data,3-D reflectivity grid data of single site,3-D mosaic reflectivity and some derived products base on mosaic base data,which are useful not only for operational work,but also for scientific research.It can run real time for the region with around fifteen radars,at intervals about 6 minutes,with the horizontal resolution of about 1 km,and at least 20 vertical height levels.Operational running on trial proves that the system is steady.Case study results show that the 3-D mosaic result with high time and spatial resolution is reliable,it provides advantage for analyzing mesoscale and small-scale severe weather,and supplies data basis for developing now-casting and some other works.Besides,the observation errors and position errors are two important cases which influence the mosaic results,and they can be determined easily by analyzing outputs of the system itself.The system is running on trial currently.It's planned to upgrade the system for business,after adding some functions and useful derived products in the near future. |
Wang J. X., D. B. Wolff, 2009: Comparisons of reflectivities from the TRMM precipitation radar and ground-based radars. J. Atmos. Oceanic Technol., 26( 5), 857- 875.10.1175/2008JTECHA1175.16aacf9e98cbdda1881bff5013c9903d8http%3A%2F%2Fwww.cabdirect.org%2Fabstracts%2F20093180776.htmlhttp://www.cabdirect.org/abstracts/20093180776.htmlNot Available |
Xu W. X., E. J. Zipser, and C. T. Liu, 2009: Rainfall characteristics and convective properties of mei-yu precipitation systems over South China, Taiwan, and the South China Sea. Part I: TRMM observations. Mon. Wea. Rev., 137( 12), 4261- 4275.10.1175/2009MWR2982.14fa94a3174570aa7ea70bc5d566c7007http%3A%2F%2Fwww.cabdirect.org%2Fabstracts%2F20103049465.htmlhttp://www.cabdirect.org/abstracts/20103049465.htmlNot Available |
Zhang D.-L., K. Gao, 1989: Numerical simulation of an intense squall line during 10-11 June 1985 PRE-STORM. Part II: Rear inflow, surface pressure perturbations and stratiform precipitation. Mon. Wea. Rev., 117, 2067- 2094.10.1175/1520-0493(1989)1172.0.CO;20d32b42a3841a42c39d776484fcf9113http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F1989MWRv..117.2067Zhttp://adsabs.harvard.edu/abs/1989MWRv..117.2067ZAbstract An intense rear-inflow jet, surface pressure perturbations, and stratiform precipitation associated with a squall line during 10-11 June 1985 are examined using a three-dimensional mesoscale nested-grid model. It is found that the large-scale baroclinity provides favorable and deep rear-to-front flow within the upper half of the troposphere and the mesoscale response to convective forcing helps enhance the trailing extensive rear inflow. However, latent cooling and water loading are directly responsible for the generation of the descending portion of the rear inflow. The role of the rear inflow is generally to produce convergence ahead and divergence behind the system, and thus assist the rapid acceleration of the leading convection when the prestorm environment is convectively favorable and the rapid dissipation of the convection when encountering unfavorable conditions. In this case study, the rear-inflow jet appears to have caused the splitting of the surface wake low as well as the organized ... |
Zhang J., K. Howard, and J. J. Gourley, 2005: Constructing three-dimensional multiple-radar reflectivity mosaics: Examples of convective storms and stratiform rain echoes. J. Atmos. Oceanic. Technol., 22, 30- 42.10.1175/JTECH-1689.1c8623dffd686de89b582aab041ef6553http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2005jatot..22...30zhttp://adsabs.harvard.edu/abs/2005jatot..22...30zThe advent of Internet-2 and effective data compression techniques facilitates the economic transmission of base-level radar data from the Weather Surveillance Radar-1988 Doppler (WSR-88D) network to users in real time. The native radar spherical coordinate system and large volume of data make the radar data processing a nontrivial task, especially when data from several radars are required to produce composite radar products. This paper investigates several approaches to remapping and combining multiple-radar reflectivity fields onto a unified 3D Cartesian grid with high spatial (=1 km) and temporal (=5 min) resolutions. The purpose of the study is to find an analysis approach that retains physical characteristics of the raw reflectivity data with minimum smoothing or introduction of analysis artifacts. Moreover, the approach needs to be highly efficient computationally for potential operational applications. The appropriate analysis can provide users with high-resolution reflectivity data that preserve the important features of the raw data, but in a manageable size with the advantage of a Cartesian coordinate system. Various interpolation schemes were evaluated and the results are presented here. It was found that a scheme combining a nearest-neighbor mapping on the range and azimuth plane and a linear interpolation in the elevation direction provides an efficient analysis scheme that retains high-resolution structure comparable to the raw data. A vertical interpolation is suited for analyses of convective-type echoes, while vertical and horizontal interpolations are needed for analyses of stratiform echoes, especially when large vertical reflectivity gradients exist. An automated brightband identification scheme is used to recognize stratiform echoes. When mosaicking multiple radars onto a common grid, a distance-weighted mean scheme can smooth possible discontinuities among radars due to calibration differences and can provide spatially consistent reflectivity mosaics. These schemes are computationally efficient due to their mathematical simplicity. Therefore, the 3D multiradar mosaic scheme can serve as a good candidate for providing high-spatial- and high-temporal-resolution base-level radar data in a Cartesian framework in real time. |
Zhao S. X., L. S. Zhang, and J. H. Sun, 2007: Study of heavy rainfall and related mesoscale systems causing severe flood in Huaihe River basin during the summer of 2007. Climatic and Environmental Research, 12( 6), 713- 727. (in Chinese)50e8509536d67caad48439d4d0da3b94http%3A%2F%2Fen.cnki.com.cn%2FArticle_en%2FCJFDTOTAL-QHYH200706002.htmhttp://xueshu.baidu.com/s?wd=paperuri%3A%28c3d78179bcef8324c1c166f0c06f83fe%29&filter=sc_long_sign&tn=SE_xueshusource_2kduw22v&sc_vurl=http%3A%2F%2Fen.cnki.com.cn%2FArticle_en%2FCJFDTOTAL-QHYH200706002.htm&ie=utf-8&sc_us=13117485720970456765 |
Zhu Y. Q., Z. H. Wang, N. Li, F. Xu, J. Han, Z. G. Chu, H. Y. Zhang, and P. C. Jiao, 2016: Consistency analysis and correction for observations from the radar at Nanjing. Acta Meteorologica Sinica, 74( 2), 298- 308. (in Chinese)81d001088cc731db3f0e6f7fb6927d7fhttp%3A%2F%2Fwww.en.cnki.com.cn%2FArticle_en%2FCJFDTotal-QXXB201602011.htmhttp://xueshu.baidu.com/s?wd=paperuri%3A%28741784071ba00e343e89a39d4d5b2f45%29&filter=sc_long_sign&tn=SE_xueshusource_2kduw22v&sc_vurl=http%3A%2F%2Fwww.en.cnki.com.cn%2FArticle_en%2FCJFDTotal-QXXB201602011.htm&ie=utf-8&sc_us=16026669959672833406 |
Zipser E. J., K. R. Lutz, 1994: The vertical profile of radar reflectivity of convective cells: A strong indicator of storm intensity and lightning probability? Mon. Wea. Rev., 122( 8), 1751- 1759.58ed312ed63308a0339f06d07c4ab51bhttp%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D1994MWRv..122.1751Z%26db_key%3DPHY%26link_type%3DABSTRACThttp://xueshu.baidu.com/s?wd=paperuri%3A%284f25dd3bd8189b0560cdb8c8fcb4e397%29&filter=sc_long_sign&tn=SE_xueshusource_2kduw22v&sc_vurl=http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D1994MWRv..122.1751Z%26db_key%3DPHY%26link_type%3DABSTRACT&ie=utf-8&sc_us=2727311449703928945 |