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

Developing a Radar Signal Simulator for the Community Radiative Transfer Model



Details

  • Journal Title:
    IEEE Transactions on Geoscience and Remote Sensing
  • Personal Author:
  • NOAA Program & Office:
    NOAA General Documents
  • Description:
    Active radar instruments provide vertically resolved clouds and precipitation measurements that cannot be provided by the passive instruments. These active measurements are not conventionally assimilated into the data assimilation systems because of the lack of fast forward radiative transfer (RT) models and also difficulties in the error modeling of the measurements. This article describes the development, evaluation, and sensitivity analysis for a forward radar model implemented in the community RT model (CRTM). The scattering properties required by the forward model are provided by the hydrometeor lookup tables that were generated using the discrete dipole approximation (DDA). The model is able to calculate both the reflectivity and the attenuated reflectivity for any given radar instrument at any given zenith angles as long as CRTM instrument-specific coefficients are available. The evaluation using CloudSat measurements shows a very good agreement between the simulations and measurements as long as the input profiles of hydrometeors are consistent with the measured reflectivity profiles. Major sources contributing to the differences between the measured and simulated reflectivities are input hydrometeor profiles, scattering lookup tables, lack of melting layer in the forward model, CRTM scattering solvers, and attenuation calculations. In addition to the forward model, both tangent linear (TL) and adjoint (AD) of the model are also implemented and tested within CRTM. These components may be required by some data assimilation systems for the assimilation of radar measurements.
  • Source:
    IEEE Transactions on Geoscience and Remote Sensing, 61, 1-13
  • DOI:
  • ISSN:
    0196-2892 ; 1558-0644
  • Format:
    PDF
  • Publisher:
    Institute of Electrical and Electronics Engineers (IEEE)
  • Document Type:
    Journal Article
  • Rights Information:
    Accepted Manuscript
  • Compliance:
    Submitted
  • Main Document Checksum:
    urn:sha-512:1fe4af1e45a778f7da40b560682d735cc35a2df475da0fa4c24985359140c4b90c2afd00dfcbff30f2f2ee883236b61db4e69bfabd20315c893f6c2ae328f9f9
  • Download URL:
  • File Type:
    Filetype[PDF - 5.96 MB ]
PREVIOUS
ON THIS PAGE
Details
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