U.S. flag An official website of the United States government.
Official websites use .gov

A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS

A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

i

A Comparison of the Impacts of Radiosonde and AMSU Radiance Observations in GSI Based 3DEnsVar and 3DVar Data Assimilation Systems for NCEP GFS



Details

  • Journal Title:
    Advances in Meteorology
  • Personal Author:
    Kutty, Govindan ; Wang, Xuguang
  • NOAA Program & Office:
    NWS (National Weather Service) ; OAR (Oceanic and Atmospheric Research)
  • Description:
    The impact of observations can be dependent on many factors in a data assimilation (DA) system including data quality control, preprocessing, skill of the model, and the DA algorithm. The present study focuses on comparing the impacts of observations assimilated by two different DA algorithms. A three-dimensional ensemble-variational (3DEnsVar) hybrid data assimilation system was recently developed based on the Gridpoint Statistical Interpolation (GSI) data assimilation system and was implemented operationally for the National Center for Environmental Prediction (NCEP) Global Forecast System (GFS). One question to address is, how the impacts of observations on GFS forecasts differ when assimilated by the traditional GSI-three dimensional variational (3DVar) and the new 3DEnsVar. Experiments were conducted over a 6-week period during Northern Hemisphere winter season at a reduced resolution. For both the control and data denial experiments, the forecasts produced by 3DEnsVar were more accurate than GSI3DVar experiments. The results suggested that the observations were better and more effectively exploited to increment the background forecast in 3DEnsVar. On the other hand, in GSI3DVar, where the observation will be making mostly local, isotropic increments without proper flow dependent extrapolation is more sensitive to the number and types observations assimilated.
  • Keywords:
  • Source:
    Advances in Meteorology, 2015, 1-17
  • DOI:
    https://doi.org/10.1155/2015/280546
  • ISSN:
    1687-9309 ; 1687-9317
  • Format:
    PDF
  • Publisher:
    Hindawi Limited
  • Document Type:
    Journal Article
  • Funding:
    Grant no. NA08OAR4320904 ; Grant no. NA12NWS4680012
  • License:
    https://creativecommons.org/licenses/by/3.0/
  • Rights Information:
    CC BY
  • Compliance:
    Library
  • Download URL:
    https://repository.library.noaa.gov/view/noaa/58971/noaa_58971_DS1.pdf
  • File Type:
    Filetype[PDF - 5.03 MB]
  • Collection(s):
    Office of Oceanic and Atmospheric Research (OAR) ; National Weather Service (NWS)
  • Main Document Checksum:
    urn:sha256:d80664dfa2bcc21ac4d9675a2a23446e0b485bddc8c39170f7b41584b63e12c1
PREVIOUS
ON THIS PAGE
Details
 Found an issue?
Send us an email at:
publishinghd@cdc.gov
The NOAA IR serves as an archival repository of NOAA-published products including scientific findings, journal articles, guidelines, recommendations, or other information authored or co-authored by NOAA or funded partners. As a repository, the NOAA IR retains documents in their original published format to ensure public access to scientific information.
BACK TO TOP