RapidScat Level 2B Climate Ocean Wind Vectors in 12.5km Footprints

2 Publications Cited this Dataset
Citation metrics available for years (2014-2022)
Processing Level2
Start/Stop Date2014-Oct-03 to 2016-Aug-19
DescriptionThis dataset contains the RapidScat Level 2B 12.5km Version 1.0 Climate quality ocean surface wind vectors. The Level 2B wind vectors are binned on a 12.5 km Wind Vector Cell (WVC) grid and processed using the using the "full aperture" normalized radar cross-section (NRCS, a.k.a. Sigma-0) from the L1B dataset. 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 61 degrees North to 61 degrees South. Furthermore, there is no consistent local time of day retrieval. This dataset is provided in a netCDF-3 file format that follows the netCDF-4 classic model (i.e., generated by the netCDF-4 API) and made available via Direct Download and OPeNDAP. For data access, please click on the "Data Access" tab above. This climate quality data set differs from the nominal "slice" L2B dataset as follows: 1) it uses full antenna footprint measurements (~20-km) without subdividing by range (~7-km) and 2) the absolute calibration has been modified for the two different low signal-to-noise ratio (SNR) mode data sets: LowSNR1 14 August 2015 to 18 September 2015; LowSNR2 6 October 2015 to 7 February 2016. The above enhancements allow this dataset to provide consistent calibration across all SNR states. Low SNR periods and other key quality control (QC) issues are tracked and kept up-to-date in PO.DAAC Drive at https://archive.podaac.earthdata.nasa.gov/podaac-ops-cumulus-docs/rapidscat/open/L1B/docs/revtime.csv. If you have any questions, please visit our user forums: https://podaac.jpl.nasa.gov/forum/.
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-May-06
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, wind, ocean, ocean wind, ocean winds, ocean surface wind vectors, surface wind vectors, wind speed, wind direction, climate, clim, cdr, climate data record, scatterometer, quikscat, seawinds, l2b, l2, level 2, level 2b, version 1, v1, version 1.0, v1.0, V1.0, 1.0
Questions related to this dataset? Contact podaac@podaac.jpl.nasa.gov
Spatial Resolution: 12.5 Kilometers x 12.5 Kilometers
Temporal Resolution: 12 Hour
Region: GLOBAL
North Bounding Coordinate: 61 degrees
South Bounding Coordinate: -61 degrees
West Bounding Coordinate: -180 degrees
East Bounding Coordinate: 180 degrees
Time Span: 2014-Oct-03 to 2016-Aug-19
Granule Time Span: 2014-Oct-03 to 2016-Aug-19
Swath Width: 900 km
Projection Type: Swath
Projection Detail: Along-track Grid
Ellipsoid: WGS 84
NameLong NameUnit
ambiguity_directionwind direction ambiguitydegrees
ambiguity_objwind objective function values1
ambiguity_speedwind speed ambiguitym s-1
atmospheric_speed_biasatmospheric speed biasm s-1
cross_track_wind_speed_biasrelative wind speed bias with respect to sweet spotm s-1
eflagsextended wind vector cell quality flagsbit
flagswind vector cell quality flagsbit
nudge_wind_directionmodel wind directiondegrees
nudge_wind_speedmodel wind speedm s-1
num_ambiguitiesnumber of ambiguous wind directions found in point-wise wind retrieval prior to spatial filtering1
number_in_aftnumber of inner aft looks in wind vector cell1
number_in_forenumber of inner forward looks in wind vector cell1
number_out_aftnumber of outer aft looks in wind vector cell1
number_out_forenumber of outer forward looks in wind vector cell1
rain_impactimpact of rain upon wind vector retrieval1
retrieved_wind_directionequivalent neutral wind direction at 10 mdegrees
retrieved_wind_speedequivalent neutral wind speed at 10 mm s-1
retrieved_wind_speed_uncorrectedwind speed without rain correctionm s-1
timedate and timeseconds since 1999-1-1 0:0:0
wind_objretrieved wind objective function value1
Citation is critically important for dataset documentation and discovery. Please cite the data as follows, and cite the reference papers when it is appropriate.
Citation RapidScat Project. 2016. Rapidscat Level 2B Climate Ocean Wind Vectors in 12.5km Footprints. Ver. 1.0. PO.DAAC, CA, USA. Dataset accessed [YYYY-MM-DD] at https://doi.org/10.5067/RSX12-L2C11

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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, with the addition of utilizing the full aperture NRCS data.]


VersionDatasetVersion DateStatus
2.0RapidScat Level 2B Climate Ocean Wind Vectors in 12.5km Footprints Version 2.02021-08-03COMPLETE2021-08-03T20:48:00.000Z
1.0RapidScat Level 2B Climate Ocean Wind Vectors in 12.5km Footprints2023-01-10COMPLETE2023-01-10T05:58:00.000Z