Search Results

You are looking at 51 - 60 of 1,366 items for :

  • Microwave observations x
  • Monthly Weather Review x
  • Refine by Access: All Content x
Clear All
Gabriel Susca-Lopata, Jonathan Zawislak, Edward J. Zipser, and Robert F. Rogers

situ datasets are used here. However, the present study expands upon previous studies by also utilizing passive microwave satellite data. The inclusion of passive microwave observations allows for a documentation of the coverage of both intense convection and at-least moderate rainfall before, during, and immediately after RI at a temporal resolution of ≤6 h. With this comprehensive collection of observations and objective analyses, the present study will further examine the relationship between

Full access
Daniel J. Cecil and Edward J. Zipser

1. Introduction Understanding, estimating, and predicting such parameters as rainfall, vertical motion, and latent heating in precipitation systems requires some understanding of the microphysical characteristics of clouds and precipitation. Hurricanes provide an excellent environment for studying precipitation processes ( Marks et al. 1998 ), as the precipitation field is long lived and generally well organized by the flow of the vortex. Black and Hallett (1986, 1999) utilize observations

Full access
Erin E. Jones, Kevin Garrett, and Sid-Ahmed Boukabara

( Andersson et al. 2007 ; Geer et al. 2014 ). In this study, we focus on the assimilation of humidity observations from the Sondeur Atmosphérique du Profil d’Humidité Intertropicale par Radiométrie (SAPHIR) on board the Megha-Tropiques satellite, which measures radiances across six channels in the 183-GHz band and allows for the retrieval of atmospheric water vapor profiles over a greater vertical range of the atmospheric column compared to other microwave humidity sounders. Efforts to directly

Full access
Hui W. Christophersen, Brittany A. Dahl, Jason P. Dunion, Robert F. Rogers, Frank D. Marks, Robert Atlas, and William J. Blackwell

system. This study utilizes the OSSE approach to demonstrate the potential impact of assimilating satellite radiances from the Time-Resolved Observations of Precipitation structure and storm Intensity with a Constellation of Smallsats (TROPICS) mission on tropical cyclone (TC) analyses and forecasts in a regional model. As part of the NASA Earth Venture-Instrument program, TROPICS will provide unprecedented rapid-refresh microwave (MW) measurements over the tropics that can be used to observe the

Restricted access
Rosanne Polkinghorne, Tomislava Vukicevic, and K. Franklin Evans

S. K. Dhall , 2006 : Dynamic Data Assimilation—A Least Squares Approach . Cambridge University Press, 654 pp . Liljegren , J. C. , 1994 : Two-channel microwave radiometer for observations of total column precipitable water vapor and cloud liquid water path. Preprints, Fifth Symp. on Global Change Studies, Nashville, TN, Amer. Meteor. Soc., 262

Full access
Robert F. Adler and Edward B. Rodgers

times. This would result in a similar increase inthe LHR inside the circle. For the present case, the LHRinside the 1- latitude circle also r. ose, by a factor >2,between 3 and 5 October observations. These relationships indicate a possible application of microwave datain helping to determine the intensity and intensitychanges of tropical cyclones. 'The LHR within 4- latitude can be thought of asbeing proportional to the product of the area coveredby precipitation and the mean precipitation

Full access
Masahiro Kazumori, Quanhua Liu, Russ Treadon, and John C. Derber

the calculated brightness temperatures with observations indicated that the new emissivity model performs better at low frequencies. A clear reduction of the wind-dependent bias was seen in the AMSR-E 10.65-GHz horizontally polarized channel. The sensitivity study showed that FASTEM-1 and the new emissivity model had a similar sensitivity to the sea surface temperature in the 6.925–89-GHz microwave frequencies. However, the new model had a much weaker sensitivity to surface wind speeds than FASTEM

Full access
G. David Alexander, James A. Weinman, and J. L. Schols

represented by using a double sine series. Hoffman and Grassoti showed that their method had significant impacts on European Centre for Medium-Range Weather Forecasts (ECMWF) analyses, and significantly reduced the variance of the difference between the analysis and microwave sensor observations of IWV. Although one of our goals here—to match forecast fields to remotely sensed observations—is the same, we employ the method of digital image warping [e.g., Pratt (1991) ], sometimes referred to as rubber

Full access
Frédéric Chevallier and Peter Bauer

earth radiation budget observations from satellites (e.g., Cess et al. 1997 ) but which only provide information relevant to bulk nonprecipitating cloud parameters. Precipitation analyses, however, require the simulation of microwave radiative transfer in the model atmosphere to be compared to available satellite data. Here, the availability of a sophisticated global operational model with simulation scales of the same order as satellite observations provides a unique tool to evaluate the model

Full access
Xin Li, Xiaolei Zou, Mingjian Zeng, Ning Wang, and Fei Tang

assimilates conventional observations and clear-sky radiances from the Advanced Microwave Sounding Unit-A (AMSU-A), the High Resolution Infrared Radiation Sounder (HIRS-4), and the ATMS using the EnVar method. For HIRS-4 infrared radiances assimilation, the GSI default minimum residual method ( Eyre and Menzel 1989 ; Li et al. 2020 ) is applied for cloud detection that discriminates clear channels based on the derived cloud top pressure. For AMSU-A and ATMS assimilation, the existing GSI quality control

Restricted access