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  • Ocean Surface Current Analyses Real-time (OSCAR) Surface Currents - Interim 0.25 Degree (Version 2.0)

    https://cmr.earthdata.nasa.gov/search/concepts/C2102959417-POCLOUD.xml
    Description:

    Ocean Surface Current Analyses Real-time (OSCAR) is a global surface current database and NASA funded research project. OSCAR ocean mixed layer velocities are calculated from satellite-sensed sea surface height gradients, ocean vector winds, and sea surface temperature gradients using a simplified physical model for geostrophy, Ekman, and thermal wind dynamics. Daily averaged surface currents are provided on a global 0.25 x 0.25 degree grid as an average over an assumed well-mixed top 30 m of the ocean from 1993 to present day. OSCAR currents are provided at three quality levels: final, interim and nrt with a respective latency of each of approximately 1 year, 1 month, and 2 days. OSCAR is generated by Earth & Space Research (ESR) https://www.esr.org/research/oscar/. More details on the source datasets, file structure, and methodology can be found in oscarv2guide.pdf.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -89.75 -180 89.75 180

    POCLOUD Short Name: OSCAR_L4_OC_INTERIM_V2.0 Version ID: 2.0 Unique ID: C2102959417-POCLOUD

  • Ocean Surface Current Analyses Real-time (OSCAR) Surface Currents - Near Real Time 0.25 Degree (Version 2.0)

    https://cmr.earthdata.nasa.gov/search/concepts/C2102958977-POCLOUD.xml
    Description:

    Ocean Surface Current Analyses Real-time (OSCAR) is a global surface current database and NASA funded research project. OSCAR ocean mixed layer velocities are calculated from satellite-sensed sea surface height gradients, ocean vector winds, and sea surface temperature gradients using a simplified physical model for geostrophy, Ekman, and thermal wind dynamics. Daily averaged surface currents are provided on a global 0.25 x 0.25 degree grid as an average over an assumed well-mixed top 30 m of the ocean from 1993 to present day. OSCAR currents are provided at three quality levels: final, interim and nrt with a respective latency of each of approximately 1 year, 1 month, and 2 days. OSCAR is generated by Earth & Space Research (ESR) https://www.esr.org/research/oscar/. More details on the source datasets, file structure, and methodology can be found in oscarv2guide.pdf.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -89.75 -180 89.75 180

    POCLOUD Short Name: OSCAR_L4_OC_NRT_V2.0 Version ID: 2.0 Unique ID: C2102958977-POCLOUD

  • Quality assurance analysis of SeaWinds-on-QuikSCAT surface winds

    https://cmr.earthdata.nasa.gov/search/concepts/C1214611911-SCIOPS.xml
    Description:

    This data set contains Quality flags for SeaWinds-on-QuikSCAT L2B unique wind ambiguity selection. A model-based approach is used to determine ambiguity selection consistency and identify possible ambiguity selection errors. A multi-level flag is produced for each L2B wind vector estimate. Related data sets: SeaWinds on QuikSCAT Level 2b Ocean Wind Vectors in 25 Km Swath Grid

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -90 -180 90 180

    SCIOPS Short Name: SeaWinds_Ambiguity_Quality Version ID: Not provided Unique ID: C1214611911-SCIOPS

  • QuikSCAT ESDR Level 2 Modeled Ocean Surface Auxiliary Fields Version 1.0

    https://cmr.earthdata.nasa.gov/search/concepts/C2491225288-POCLOUD.xml
    Description:

    This dataset contains the first provisional release of the MEaSUREs-funded Earth Science Data Record (ESDR) of ancillary data corresponding to the QuikSCAT Level 2 (L2) data products, interpolated in space and time to the scatterometer observations. These ancillary files include: i) ocean surface wind fields from ERA-5 short-term forecasts (removed from the analyses times to reduce impacts from assimilated scatterometer retrievals at the beginning of the forecast); ii) collocated in space and time estimations of precipitation from the GPM IMERG product; iii) estimation of the surface currents from the GlobeCurrent project. These auxiliary fields are included to complement the scatterometer observation fields and to help in the evaluation process. The primary purpose of this release is for provisional evaluation to be provided by the NASA International Ocean Vector Winds Science Team (IOVWST). As such, this release is not intended for science-quality research, and is subject to future revision based on feedback provided by the IOVWST. The modeled ocean surface auxiliary fields are provided on a non-uniform grid within the native L2 QuikSCAT sampled locations at 12.5 km pixel resolution. Each file corresponds to a specific orbital revolution (rev) number, which begins at the southernmost point of the ascending orbit.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -90 -180 90 180

    POCLOUD Short Name: QSCAT_ESDR_MODELED_L2_AUX_V1.0 Version ID: 1.0 Unique ID: C2491225288-POCLOUD

  • QuikSCAT Level 1C Averaged Sigma-0 and Winds from Non-spinning Antenna Version 2.0

    https://cmr.earthdata.nasa.gov/search/concepts/C2617177020-POCLOUD.xml
    Description:

    This dataset is Version 2 of the geo-located and averaged Level 1B Sigma-0 measurements and wind retrievals from the SeaWinds on QuikSCAT platform, initiated in the months following the failure of the rotating antenna motor on 22 November 2009, using the various incidence angles at which QuikSCAT was pointed during the time period from November 2009 until present. Incidence angles were varied in order to cross-calibrate the Oceansat-2 and RapidScat scatterometers and to extend the known Ku-band geophysical model function. The averaging of the L1B input data combined with the wind vector processing results are both contained in this product referred to hereafter as Level 1C (L1C). The fixed and repointed beam processing is relative to either the one corresponding to the vertically polarized "outer" beam or the other corresponding to the horizontally polarized "inner" beam. The Sigma-0 values from the fixed operating beam for each frame are averaged to a single value representing approximately 50 samples. The data points are land flagged, collocated with ECMWF surface winds, and have climatological nadir attenuations provided for the location and time of the data (not applied to the sigma0). The following enhancements have been applied in the Version 2 re-processing: 1) the GMF has been updated (QNS2016a) to make use of ECMWF nowcast 1x1 degree resolution wind direction information for the entire historical data record; 2) the new QNS2016a GMF leverages a calibration adjustment from Remote Sensing Systems (RSS) resulting in a consistently lower Normalized Radar Cross Section (NRCS or Sigma-0) measurements that establishes a Sigma-0 bias of -0.25 dB (-5.9% linear scale) compared to the L1C Version 1 data; 3) the new QNS2016a GMF also applies an azimuthal modulation that is decreased by several tenths of a dB (for Sigma-0) in variation with wind speed; this results in a more consistent wind speed retrieval comparison between "non-spinning" and "spinning" modes of the QuikSCAT instrument; 4) spacecraft attitude was re-estimated using slice data over multiple orbits as a replacement for lost echo-tracking capability during the "non-spinning" mode of the instrument; this new attitude estimation follows an unpublished manual technique that leverages the echo power of individual slice observations; since only a small subset of slice observations are analyzed, rapid variations in attitude are not captured; 5) continues data production beyond October 2016 through the end of mission on 30 August 2018. Retrieved wind directions are only slightly different from ECMWF values and should not be considered an independent measurement of wind direction. Retrieved wind speeds do not depend significantly on ECMWF speeds as evidenced by the fact that they agree closely with WindSAT polarimetric radiometer speeds whenever WindSAT and ECMWF disagree. The Sigma0 values have also been corrected for scan loss (due to the fact that the antenna does not scan) and for X-factor changes due to repointing.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -89.875 -180 89.875 180

    POCLOUD Short Name: QSCAT_L1C_NONSPINNING_SIGMA0_WINDS_V2 Version ID: 2.0 Unique ID: C2617177020-POCLOUD

  • QuikSCAT Level 2B Ocean Wind Vectors in 12.5km Slice Composites Version 3

    https://cmr.earthdata.nasa.gov/search/concepts/C2526576230-POCLOUD.xml
    Description:

    This dataset contains the latest reprocessed version 3 of the Level 2B science-quality ocean surface wind vector retrievals from the QuikSCAT scatterometer. The retrievals are provided on a non-uniform grid within the swath at 12.5 km pixel resolution. Higher resolution is achieved through a slice composite technique in which high resolution slice measurements from L1B data are composited into a 12.5 km wind vector cell. Version 3 processing begins with the same L1B (time-ordered backscatter) data as used in the previous processing. Version 3 has several improvements over the previous JPL processing of the QuikSCAT L2B winds: 1) changes to measurement binning, which was done in order to decrease noise and reduce gaps in the 12.5 km L2B wind retrievals, 2) an improved geophysical model function (GMF) to model the effect of wind on backscatter, 3) a neural network approach to correct rain contaminated winds speeds, 4) cross-track dependent wind speed biases were estimated and removed from the wind retrievals. The 12.5 km binning resolution enables users to obtain wind vector retrievals 10 km closer to shore when compared to the 25 km L2B dataset (only available in versions 1 and 2). More details to the processing changes and improvements are noted by Fore et al. (2014): PO.DAAC Drive at https://podaac-tools.jpl.nasa.gov/drive/files/allData/quikscat/L2B12/docs/fore_et_al_ieee_2014.pdf . Each L2B file corresponds to a specific orbital revolution (rev) number, which begins at the southernmost point of the ascending orbit. This is the official dataset produced by the QuikSCAT Project through the SeaWinds Processing and Analysis Center (SeaPAC). The Version 3 User Guide document is accessible from https://archive.podaac.earthdata.nasa.gov/podaac-ops-cumulus-docs/quikscat/open/L2B12/docs/qscat_l2b_v3_ug_v1_0.pdf.

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    Minimum Bounding Rectangle: -90 -180 90 180

    POCLOUD Short Name: QSCAT_LEVEL_2B_OWV_COMP_12 Version ID: 3 Unique ID: C2526576230-POCLOUD

  • QuikSCAT Level 2B Ocean Wind Vectors in 12.5km Slice Composites Version 3.1

    https://cmr.earthdata.nasa.gov/search/concepts/C2036882492-POCLOUD.xml
    Description:

    This dataset contains the latest reprocessed version 3.1 of the Level 2B science-quality ocean surface wind vector retrievals from the QuikSCAT scatterometer. The retrievals are provided on a non-uniform grid within the swath at 12.5 km pixel resolution. Higher resolution is achieved through a slice composite technique in which high resolution slice measurements from L1B data are composited into a 12.5 km wind vector cell. Version 3.1 processing begins with the same L1B (time-ordered backscatter) data as used in the previous Version 3.0 processing. Version 3.1 improves upon the previous Version 3.0 processing by incorporating enhanced coastal processing using a Land Contamination Ratio (LCR) method with a fixed threshold. The 12.5 km binning resolution combined with the LCR processing enables this dataset to provide wind vector retrievals with approximately half the coastal gap as compared to the Version 3.0 12.5 km L2B dataset. The geophysical model function used to produce the wind vector cell retrievals remains unchanged between Version 3.0 and 3.1. Each L2B file corresponds to a specific orbital revolution (rev) number, which begins at the southernmost point of the ascending orbit. This is the official dataset produced by the NASA QuikSCAT Project through the SeaWinds Processing and Analysis Center (SeaPAC). More details to the processing changes and improvements are to be published in the near future, but for now can be referenced by the following presentation: https://mdc.coaps.fsu.edu/scatterometry/meeting/docs/2016/Thu_AM/coastal-poster.pdf .

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -90 -180 90 180

    POCLOUD Short Name: QSCAT_LEVEL_2B_OWV_COMP_12_LCR_3.1 Version ID: 3.1 Unique ID: C2036882492-POCLOUD

  • QuikSCAT Level 2B Ocean Wind Vectors in 12.5km Slice Composites Version 4.1

    https://cmr.earthdata.nasa.gov/search/concepts/C2036882397-POCLOUD.xml
    Description:

    This dataset contains the latest reprocessed version 4.1 of the Level 2B science-quality ocean surface wind vector retrievals from the QuikSCAT scatterometer. The retrievals are provided on a non-uniform grid within the swath at 12.5 km pixel resolution. Higher resolution is achieved through a slice composite technique in which high resolution slice measurements from L1B data are composited into a 12.5 km wind vector cell. Each L2B file corresponds to a specific orbital revolution (rev) number, which begins at the southernmost point of the ascending orbit. This is an official dataset produced by the NASA QuikSCAT Project through the SeaWinds Processing and Analysis Center (SeaPAC). Version 4.1 processing begins with the same L1B (time-ordered backscatter) data as used in the previous Version 4.0 processing. This new version has a number of key improvements and changes over the previous version 4.0, including: 1) winds are now retrieved to within 5-km and 10-km of the coast within oceans/seas and lakes respectively; 2) coastal winds are now flagged as poor coastal quality and likely corrupted in orbits with estimated spacecraft pitch error greater than 0.04 degrees, which affects 150 orbits of data where coastal winds are severely contaminated by land due to poor attitude knowledge (note: attitude error tracking can identify pitch error but not yaw error, so when estimated pitch error is far from zero, it implies yaw error is large and uncorrected); 3) coastal winds are flagged based upon the long term mean wind speed and standard deviation of wind speed for each place on the ground; 4) four quantities, means and standard deviations computed with and without the land contamination correction algorithm applied (note: higher mean and smaller standard deviation are evidence of land contamination), are used to estimate the expected wind speed bias with respect to neighboring wind vector cells over open water; 5) wind vector cells with estimated speed bias greater than 0.4 m/s are flagged as poor coastal quality and likely corrupted; 6) winds within 5-km of the coast of an ocean/sea and 10-km of the coast of a lake are flagged as poor coastal quality and likely corrupted; the larger distance threshold for lakes is due to higher variability in lake water levels.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -90 -180 90 180

    POCLOUD Short Name: QSCAT_LEVEL_2B_OWV_COMP_12_KUSST_LCRES_4.1 Version ID: 4.1 Unique ID: C2036882397-POCLOUD

  • QuikSCAT Scatterometer Inter-Calibrated ESDR Level 2 Ocean Surface Equivalent Neutral Wind Vectors and Wind Stress Vectors Version 1.0

    https://cmr.earthdata.nasa.gov/search/concepts/C2491137146-POCLOUD.xml
    Description:

    This dataset contains the first provisional release of the MEaSUREs-funded Earth Science Data Record (ESDR) of inter-calibrated ocean surface wind vectors (equivalent neutral and true 10m) and wind stress vectors derived from QuikSCAT scatterometer observations. The primary purpose of this release is for provisional evaluation by the NASA International Ocean Vector Winds Science Team (IOVWST). As such, this release is not intended for science-quality research, and is subject to future revision based on feedback provided by the IOVWST. The wind vector and stress retrievals are provided on a non-uniform grid within the swath (Level 2 (L2) products) at 12.5 km pixel resolution. Each L2 file corresponds to a specific orbital revolution (rev) number, which begins at the southernmost point of the ascending orbit.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -90 -180 90 180

    POCLOUD Short Name: QUIKSCAT_ESDR_L2_WIND_STRESS_V1.0 Version ID: 1.0 Unique ID: C2491137146-POCLOUD

  • QuikSCAT Scatterometer Inter-Calibrated ESDR Level 3 Ocean Surface Equivalent Neutral Wind Vectors and Wind Stress Version 1.0

    https://cmr.earthdata.nasa.gov/search/concepts/C3403218558-POCLOUD.xml
    Description:

    This dataset contains gridded ocean surface wind vectors (equivalent neutral and true 10m) and wind stress vectors derived from satellite-based scatterometer observations aboard QuikScat, representing the first science quality release of these data funded under the MEaSUREs program. This product from QuikScat has been intercalibrated with similar scatterometer measurements from instruments on the MetOp-A, MetOp-B, and ScatSat-1. The wind vector and stress retrievals are provided on a global grid (one per file) at 12.5 km pixel resolution, but data exist only over areas of the globe that fell within one of the satellite swaths/orbits for that day (see thumbnail). <br><br> The dataset represents the first science quality release funded under the MEaSUREs (Making Earth System Data Records for Use in Research Environments) program. Note that this is the first version of the Level 3 data (V1.0) but they were derived from V1.1 of the Level 2 product. The primary purpose of this release is for science evaluation by the NASA International Ocean Vector Winds Science Team (IOVWST).

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -90 -180 90 180

    POCLOUD Short Name: QUIKSCAT_ESDR_L3_WIND_STRESS_V1.0 Version ID: 1.0 Unique ID: C3403218558-POCLOUD