RapidScat Level 2A Surface Flagged Sigma-0 and Attenuations in 25Km Swath Grid Version 1.2
Short NameRSCAT_L2A_25KM_V1.2
DescriptionThis dataset contains the Version 1.2 ISS-RapidScat Level 2A 25km science data record, which provides surface-flagged sigma-0 in 25km Wind Vector Cells processed using the pulse "egg" Sigma-0 data provided by the Level 1B dataset. Version 1.2 is intended as a replacement and continuation of the Version 1.1 data forward from orbital revolution number 5127, corresponding to 19 August 2015; the overlapping time period starting on 19 August 2015 corresponds to the first time period of the recorded low signal-to-noise ratio (SNR). This Version 1.2 dataset differs from the previous Version 1.1 dataset as follows: 1) L1B sigma-0 has been re-calibrated during the periods of low signal-to-noise ratio (SNR) and 2) during low SNR periods the L1B sigma-0 calibration is determined using re-pointed L1B QuikSCAT data. Due to the circular scan of the SeaWinds instrument the expected number of Sigma-0 cells per WVC is not constant. To minimize the L2A data volume, the Sigma-0 cell data are stored as "lists" for each WVC row, with each list indexed by a "cell_index" array to indicate the cross-track WVC membership of the data. Each cell is then checked for land or ice and flagged accordingly. Attenuation corrections for each Sigma-0 measurement are also provided. Data are provided in single-orbit files in HDF-4 format. RapidScat is a Ku-band dual beam circular rotating scatterometer retaining much of the same hardware and functionality of QuikSCAT, with exception of the antenna sub-system and digital interface to the International Space Station (ISS) Columbus module, which is where RapidScat is mounted. The NASA mission is officially referred to as ISS-RapidScat. Unlike QuikSCAT, ISS-RapidScat is not in sun-synchronous orbit, and flies at roughly half the altitude with a low inclination angle that restricts data coverage to the tropics and mid-latitude regions; the extent of latitudinal coverage stretches from approximately 56 degrees North to 56 degrees South. Furthermore, there is no consistent local time of day retrieval. If you have any questions or concerns, please visit our Forum at https://podaac.jpl.nasa.gov/forum/.
Dataset TypeCOMPLETE
Processing Level2A
CoverageRegion: GLOBAL
North Bounding Coordinate: 61 degrees
South Bounding Coordinate: -61 degrees
West Bounding Coordinate: -180 degrees
East Bounding Coordinate: 180 degrees
Time Span: 2015-Aug-19 to 2016-Aug-19
Granule Time Span: 2015-Aug-19 to 2016-Aug-19
ResolutionSpatial Resolution: 25 km (Along) x 25 km (Across)
ProjectionEllipsoid: WGS 84
Swath Width900 km
Name: International Space Station (ISS)
Orbit Period: 92.91 minutes
Inclination Angle: 51.65 degrees
Name: Rapid Scatterometer (RapidScat)
Swath Width: 1100.0 kilometers
Description: Spacecraft angular distance from orbital plane relative to the Equator.

ProjectInternational Space Station Rapid Scatterometer (ISS_RapidScat)
Data ProviderPublisher: PO.DAAC
Creator: RapidScat Project
Release Place: PO.DAAC
Release Date: 2016-Apr-18
Resource: http://www.jpl.nasa.gov/news/fact_sheets/issrapidscat_factsheet.pdf

Keyword(s)international space station, space station, iss, rapidscat, rscat, iss-rapidscat, winds, radar, ocean, roughness, ocean roughness, backscatter, normalized radar cross-section, normalized radar cross section, nrcs, dB, sigma-0, sigma0, sigma naught, scatterometer, seawinds, l2a, l2, level 2, level 2a, 25 km, 25-km, 25, version 1, v1, version 1.2, v1.2, V1.2, 1.2
Questions related to this dataset? Contact podaac@podaac.jpl.nasa.gov
Direct Access
PO.DAAC DRIVEhttps://podaac-tools.jpl.nasa.gov/drive/files/allData/rapidscat/L2A/25km/v1.2
OPENDAP DATAhttps://podaac-opendap.jpl.nasa.gov/opendap/allData/rapidscat/L2A/25km/v1.2/
The OPeNDAP base directory location for the collection.
Format (Compression)HDF
Citation RapidScat Project. 2016. RapidScat Level 2A Surface Flagged Sigma-0 and Attenuations in 25Km Swath Grid Version 1.2. Ver. 1.2. PO.DAAC, CA, USA. Dataset accessed [YYYY-MM-DD] at https://doi.org/10.5067/RSX25-L2A12

Download Citation

For more information see Data Citations and Acknowledgments.

Journal Reference Fore, A.G., Stiles, B.W., Chau, A.H., Williams, B.A., Dunbar, R. S., Rodriguez E., 2013: Point-wise Wind Retrieval and Ambiguity Removal Improvements for the QuikSCAT Climatological Data Set. IEEE Trans. Geoscience and Remote Sensing, doi:10.1109/TGRS.2012.2235843. [Special Note: This paper describes the wind retrieval algorithm used to process the QuikSCAT version 3 wind product. The RapidScat data was processed using the same technique.]