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MODIS/Aqua Calibrated Radiances 1km 5-Min 1B Wide Swath Subset along CloudSat V002 (MAC021S1) at GES DISC

This is the wide-swath MODIS/Aqua subset along CloudSat field of view track. The goal of the wide-swath subset is to select and return MODIS data that are within +-100 km across the CloudSat track. I.e. the resultant MODIS subset swath is about 200 km cross-track. Thus, MAC021S1 cross-track width is 201 pixels for radiances. Geolocations in the original product, however, are subsampled at 5-km, and thus the cross-track width of the subset geolocations is 41 pixels. Along-track, all MODIS pixels from the original product are preserved. In the standard product, the MODIS Level 1B data set contains calibrated and geolocated at-aperture radiances for 36 discrete bands located in the 0.4 to 14.4 micron region of electromagentic spectrum. These data are generated from the MODIS Level 1A scans of raw radiance and in the process converted to geophysical units of W/(m^2 um sr). In addition, the Earth Bi-directional Reflectance Distribution Function (BRDF) may be determined for the solar reflective bands (1-19, 26) through knowledge of the solar irradiance (e.g., determined from MODIS solar diffuser data, and from the target illumination geometry). Additional data are provided including quality flags, error estimates and calibration data. Visible, shortwave infrared, and near infrared measurements are only made during the daytime, while radiances for the thermal infrared region (bands 20-25, 27-36) are measured continuously. (The shortname for this product is MAC021S1).

TRMM Microwave Imager Calibrated Radiances L1B 1.5 hours V7 (TRMM_1B11) at GES DISC

This dataset contains TRMM Micrwave Imager (TMI) L1B calibrated radiances in terms of Brightness Temperatures. The TMI calibration algorithm (1B11) converts the radiometer counts to antenna temperatures by applying a linear relationship of the form Ta = c1 + c2 x count. The coefficients are provided by the instrument contractor. Antenna temperatures are corrected for cross-polarization and spill over to produce brightness temperatures (Tb), but no antenna beam pattern correction or sample to pixel averaging are performed. Temperatures are provided at 104 scan positions for the low frequency channels and 208 scan positions at 85 GHz. There are four samples per pixel (3 -dB beamwidth) at 10 GHz, two samples at 19, 22, and 37 GHz, and one sample per pixel for the 85 GHz. Data Flow Description Changes in horizontal resolution resulting from the TRMM boost that occurred on 24 August 2001: Pre-Boost (before 7 August 2001): Temporal Resolution: 91.5 min/orbit ~ 16 orbits/day; Swath Width: 760 km; Horizontal Resolution: 4.4 km Post-Boost (after 24 August 2001): Temporal Resolution: 92.5 min/orbit ~ 16 orbits/day; Swath Width: 878 km; Horizontal Resolution: 5.1 km

Reduced Resolution Geolocated and Calibrated TOA Radiance

The Medium Resolution Imaging Spectrometer (MERIS) is one of 10 sensors deployed in March of 2002 on board the polar-orbiting Envisat-1 environmental research satellite by the European Space Agency (ESA). The MERIS instrument is a moderate-resolution wide field-of-view push-broom imaging spectroradiometer capable of sensing in the 390 nm to 1040 nm spectral range. Being a programmable instrument, it had the unique capability of selectively adjusting the width and location of its 15 bands through ground command. The instrument has a 68.5-degree field of view and a swath width of 1150 meters, providing a global coverage every 3 days at 300 m resolution. Communication with the Envisat-1 satellite was lost suddenly on the 8th of April, 2012, just weeks after celebrating its 10th year in orbit. All attempts to re-establish contact were unsuccessful, and the end of the mission was declared on May 9th, 2012.The 4th reprocessing cycle, in 2020, has produced both the full-resolution and reduced-resolution L1 and L2 MERIS products. EN1_MDSI_MER_RR__1P is the short-name for the MERIS Level-1 reduced resolution, geolocated and calibrated top-of-atmosphere (TOA) radiance product. This product contains the TOA upwelling spectral radiance measurements at reduced resolution. The in-band reference irradiances for the 15 MERIS bands are computed by averaging the in-band solar irradiance for each pixel. Each pixel’s in-band solar irradiance is computed by integrating the reference solar spectrum with the band-pass of each pixel. The Level-1 product contains 22 data files: 15 files contain radiances for each band (one band per file) along with associated error estimates, and 7 annotation data files. It also includes a Manifest file that provides metadata information describing the product.

OCO-2 Level 1A collated, parsed, calibration data V10 (OCO2_L1aIn_Pixel) at GES DISC

Version 10 is the current version of the data set. Older versions will no longer be available and are superseded by Version 10. The Orbiting Carbon Observatory is the first NASA mission designed to collect space-based measurements of atmospheric carbon dioxide with the precision, resolution, and coverage needed to characterize the processes controlling its buildup in the atmosphere. The OCO-2 project uses the LEOStar-2 spacecraft that carries a single instrument. It incorporates three high-resolution spectrometers that make coincident measurements of reflected sunlight in the near-infrared CO2 near 1.61 and 2.06 micrometers and in molecular oxygen (O2) A-Band at 0.76 micrometers. The three spectrometers have different characteristics and are calibrated independently. Their raw data numbers (DN) are delivered correlated in time to the Level 1B process as Level 1A products. Each band has 1016 spectral elements, although some are masked out in the L2 retrieval.This product is the input to the Level 1B process. It is depacketized raw data formatted into a standard granularity with calibrated engineering data (for both science and calibration observations), in the Single-pixel Mode of operation.

VIIRS/JPSS2 Moderate-Resolution Dual Gain Bands Calibrated Radiance 6-Min L1B Swath 750m NRT

The Near Real Time (NRT) VIIRS/JPSS2 Moderate-Resolution Dual Gain Bands Calibrated Radiance 6-Min L1B Swath 750m product (VJ202GDC_NRT) contains unaggregated, calibrated TOA radiances for those VIIRS sub-pixel samples that are aggregated along-scan during post-calibration ground processing. In other words, this file contains the calibrated M1 – M5, M7 and M13 dual gain band data from the nadir and near-nadir zones that would otherwise be discarded following post-calibration aggregation/Earth View Radiometric Calibration Unit.The Level-1 and Level-2 swath products are generated from the processing of 6 minutes of VIIRS data acquired during theJPSS-2/NOAA-21 satellite overpass. The VIIRS sensor has 5 high-resolution imagery channels (I-bands) that have 32 detectors (32 rows of pixels per scan), with twice the resolution of the M-bands and the DNB, that span the wavelengths from 0.640 µm to 11.45 µm. There are also 7 dual-gain VIIRS bands. The dual gain moderate resolution bands (M1 to M5, M7 and M13) have 6304 samples and the other moderate resolution bands have 3200.For additional information, see the Operational Algorithm Description (OAD) Document for the L1B product at http://npp.gsfc.nasa.gov/sciencedocs/2015-08/474-00090_OAD-VIIRS-CAL-GEO-SDR_H.pdf. The document describes how VIIRS operates in space and provides the equations implemented by the L1B software to generate the MODIS Level-1 intermediate products. It is a summary document that presents the formulae and error budges used to transform VIIRS digital counts to radiance and reflectance.

OCO-2 Level 1B calibrated, geolocated science spectra V11.2 (OCO2_L1B_Science) at GES DISC

Version 11.2 is the current version of the data set. Older versions will no longer be available and are superseded by Version 11.2. The Orbiting Carbon Observatory is the first NASA mission designed to collect space-based measurements of atmospheric carbon dioxide with the precision, resolution, and coverage needed to characterize the processes controlling its buildup in the atmosphere. The OCO-2 project uses the LEOStar-2 spacecraft that carries a single instrument. It incorporates three high-resolution spectrometers that make coincident measurements of reflected sunlight in the near-infrared CO2 near 1.61 and 2.06 micrometers and in molecular oxygen (O2) A-Band at 0.76 micrometers. The three spectrometers have different characteristics and are calibrated independently. Their raw data numbers (DN) are delivered correlated in time to the Level 1B process as Level 1A products. Each band has 1016 spectral elements, although some are masked out in the L2 retrieval.This product is the output from the Level 1B process. It converts the raw instrument data numbers into calibrated radiances. This conversion is based upon files of instrument characteristics and algorithm parameters that may vary over time. In addition to calibrated radiances, the Level 1B output products have geolocation information recorded for each measurement for use in higher-level processes.

Sentinel-6A MF Jason-CS L1A P4 Altimeter High Resolution (HR) STC Intermediate Outputs with Instrument Calibrations

Provides L1A high resolution (HR) short time critical (STC; 36-hour latency) altimetry intermediate outputs from the Poseidon-4 SAR altimeter on the Sentinel-6A Michael Freilich spacecraft, which are geo-located bursts of Ku-band echoes (at ~140 Hz) with all instrument calibrations applied and full rate complex waveforms for delay/Doppler or HR processing. The S6A STC product is analogous to the Jason-3 IGDR product.

THIR/Nimbus-7 Level 1 Calibrated Located Radiation Data at 6.7 and 11.5 microns V001 (THIRN7L1CLDT) at GES DISC

THIRN7L1CLDT is the Nimbus-7 Temperature-Humidity Infrared Radiometer (THIR) Level 1 Calibrated Located Radiation Data (CLDT) at 6.7 and 11.5 microns product and contains radiances expressed in units of W/m2/sr measured in the 10.5 - 12.5 (11.5) micron and 6.5 - 7.0 (6.7) micron channels. The data, originally written on IBM 360 machines, were recovered from magnetic 9-track tapes. The data are archived in their original proprietary format. The Nimbus-7 satellite was successfully launched on October 28, 1978. The Temperature-Humidity Infrared Radiometer (THIR) experiment on Nimbus-7 is basically identical to its predecessors flown on Nimbus-4, -5 and -6, except that the data were digitized on board. The THIR instrument is a two channel high resolution scanning radiometer designed to perform two major functions:* The 11.5 micron channel provides both day and night cloud top or surface temperatures. The ground resolution at the sub-point is 6.7 km and operates day and night.* The 6.7 micron channel gives information on the moisture content of the upper troposphere and stratosphere and the location of jet streams and frontal systems. The water vapor channel has a resolution of the sub-point is 20 km and operates mostly at night. The THIR Principal Investigator was Dr. Larry L. Stowe from NOAA NESDIS. The Nimbus-7 THIR data are available from October 30, 1979 (day of year 303) through May 13, 1985 (day of year 133). This product was previously available from the NSSDC with the identifier ESAD-00107 (old ID 78-098A-10C).

NPP/VIIRS Moderate-Resolution Dual Gain Bands Calibrated Radiance 6 Min L1B Swath 750m NRT

The NPP/VIIRS Moderate-Resolution Dual Gain Bands Calibrated Radiance 6-Min L1B Swath 750m Near Real Time (NRT) product, short-name VNP02GDC, contains unaggregated, calibrated TOA radiances for those VIIRS sub-pixel samples that are aggregated along-scan during post-calibration ground processing. In other words, this file contains the calibrated M1- M5, M7 and M13 dual gain band data from the nadir and near-nadir zones that would otherwise be discarded following post-calibration aggregation/Earth View Radiometric Calibration Unit.The VIIRS Level-1 and Level-2 swath products are generated from the processing of 6 minutes of VIIRS data acquired during the NPP satellite overpass. The VIIRS sensor has 5 high-resolution imagery channels (I-bands) that have 32 detectors (32 rows of pixels per scan), with twice the resolution of the M-bands and the DNB, that span the wavelengths from 0.640 micron to 11.45 micron. There are also 7 dual-gain VIIRS bands. The dual gain moderate resolution bands (M1 to M5, M7 and M13) have 6304 samples and the other moderate resolution bands have 3200.For additional information, see the Algorithm Theoretical Basis Document (ATBD) for the L1B product (https://ladsweb.modaps.eosdis.nasa.gov/missions-and-measurements/viirs/NASARevisedJPSSVIIRSRadCalATBD2014.pdf). The document describes how VIIRS operates in space and provides the equations implemented by the L1B software to generate the MODIS Level-1 intermediate products. It is a summary document the presents the formulae and error budges used to transform VIIRS digital counts to radiance and reflectance.

MODIS/Terra Near Real Time (NRT) Calibrated Radiances 5-Min L1B Swath 1km

The MODIS Level 1B Near Real Time (NRT) data set contains calibrated and geolocated at-aperture radiances for 36 discrete bands located in the 0.4 to 14.4 micron region of electromagentic spectrum. These data are generated from the MODIS Level 1A scans of raw radiance and in the process converted to geophysical units of W/(m^2 um sr). In addition, the Earth Bi-directional Reflectance Distribution Function (BRDF) may be determined for the solar reflective bands (1-19, 26) through knowledge of the solar irradiance (e.g., determined from MODIS solar diffuser data, and from the target illumination geometry). Additional data are provided including quality flags, error estimates and calibration data. Visible, shortwave infrared, and near infrared measurements are only made during the daytime, while radiances for the thermal infrared region (bands 20-25, 27-36) are measured continuously. Channel locations for MODIS are as follows: Band Center Wavelength (um) Primary Use---- ---------------------- -----------1 0.620 - 0.670 Land/Cloud Boundaries2 0.841 - 0.876 Land/Cloud Boundaries3 0.459 - 0.479 Land/Cloud Properties4 0.545 - 0.565 Land/Cloud Properties5 1.230 - 1.250 Land/Cloud Properties6 1.628 - 1.652 Land/Cloud Properties7 2.105 - 2.155 Land/Cloud Properties8 0.405 - 0.420 Ocean Color/Phytoplankton9 0.438 - 0.448 Ocean Color/Phytoplankton10 0.483 - 0.493 Ocean Color/Phytoplankton11 0.526 - 0.536 Ocean Color/Phytoplankton12 0.546 - 0.556 Ocean Color/Phytoplankton13 0.662 - 0.672 Ocean Color/Phytoplankton14 0.673 - 0.683 Ocean Color/Phytoplankton15 0.743 - 0.753 Ocean Color/Phytoplankton16 0.862 - 0.877 Ocean Color/Phytoplankton17 0.890 - 0.920 Atmospheric Water Vapor18 0.931 - 0.941 Atmospheric Water Vapor19 0.915 - 0.965 Atmospheric Water Vapor20 3.660 - 3.840 Surface/Cloud Temperature21 3.929 - 3.989 Surface/Cloud Temperature22 3.929 - 3.989 Surface/Cloud Temperature23 4.020 - 4.080 Surface/Cloud Temperature24 4.433 - 4.498 Atmospheric Temperature25 4.482 - 4.549 Atmospheric Temperature26 1.360 - 1.390 Cirrus Clouds27 6.535 - 6.895 Water Vapor Profile28 7.175 - 7.475 Water Vapor Profile29 8.400 - 8.700 Water Vapor Profile30 9.580 - 9.880 Ozone Overburden31 10.780 - 11.280 Surface/Cloud Temperature32 11.770 - 12.270 Surface/Cloud Temperature33 13.185 - 13.485 Cloud Top Altitude34 13.485 - 13.785 Cloud Top Altitude35 13.785 - 14.085 Cloud Top Altitude36 14.085 - 14.385 Cloud Top Altitude Channels 1 and 2 have 250 m resolution, channels 3 through 7 have 500m resolution, and the rest have 1 km resolution. However, for the MODIS L1B 1 km product, the 250 m and 500 m band radiance data and their associated uncertainties have been aggregated to 1km resolution. Thus the entire channel data set is referenced to the same spatial and geolocation scales. Separate L1B products are available for the 250 m channels (MOD02QKM) and 500 m channels (MOD02HKM) that preserve the original resolution of the data. Spatial resolution for pixels at nadir is 1 km, degrading to 4.8 km in the along-scan direction at the scan extremes. However, thanks to the overlapping of consecutive swaths and respectively pixels there, the resulting resolution at the scan extremes is about 2km. A 55 degree scanning pattern at the EOS orbit of 705 km results in a 2330km orbital swath width and provides global coverage every one to two days. A single MODIS Level 1B granule will nominally contain a scene built from 203 scans (or swaths) sampled 1354 times in the cross-track direction, corresponding to approximately 5 minutes worth of data. Since an individual MODIS scan (or swath) will contain 10 along-track spatial elements, the scene will be composed of (1354 x 2030) pixels, resulting in a spatial coverage of (2330 km x 2030 km). Due to the MODIS scan geometry, there will be increasing overlap occurring beyond about 25 degrees scan angle. To summarize, the MODIS L1B 1 km data product consists of: 1. Calibrated radiances and uncertainties for (2) 250 m reflected solar bands aggregated to 1km resolution 2. Calibrated radiances and uncertainties for (5) 500 m reflected solar bands aggregat

TRMM Ground Validation Calibrated QC Radar Reflectivity Full Volume Scan L1C 1 hour V7 (TRMM_1C51UW) at GES DISC

This dataset is part of the University of Washington TRMM Ground Validation products. Files are in "Universal Format", described in BAMS, Vol 61, No 11, November 1980, pp. 1401-1404. The purpose of the 1C51UW algorithm is to remove non-meteorological radar echoes that adversely affect the quality of higher level products, such as clutter associated with insects, birds, chaff, wildfires, antenna towers, and anomalous propagation (AP). Eight adjustable parameters, three echo height thresholds and five radar reflectivity thresholds, are used to optimize the performance of the algorithm. Optimum performance is time consuming and requires an analyst to select different sets of parameters on a per volume scan basis, and on occasions performing several iterations while adjusting one or more of the parameters. A key component of the TRMM project is the Ground Validation (GV) effort which consists of collecting data from ground-based radar, rain gauges and disdrometers. The data is quality-controlled, and then validation products are produced for comparison with TRMM satellite products. The four primary GV sites are: + Darwin, Australia; + Houston, Texas; + Kwajalein, Republic of the Marshall Islands; + Melbourne, Florida. A significant effort is also being supported at NASA Wallops Flight Facility (WFF) and vicinity to provide high quality, long-term measurements of rain rates (via a network of rain gauges collocated with National Weather Service gauges), as well as drop size distributions (DSD) using a variety of instruments, including impact-type Joss Waldvogel, laser-optical Parsivel, as well as two-dimensional video disdrometers. DSD measurements are also being collected at Melbourne and Kwajalein using Joss-Waldvogel disdrometers.

MODIS/Aqua Calibrated Radiances 250m 5-Min L1B Narrow Swath Subset along CloudSat V002 (MAC02QS0) at GES DISC

This is the narrow-swath MODIS/Aqua subset along CloudSat field of view track. The goal of the narrow-swath subset is to select and return MODIS data that are within +-5 km across the CloudSat track. I.e. the resultant MODIS subset swath is about 10 km cross-track. Thus, MAC02QS0 cross-track width is 44 pixels for radiances. Geolocations, however, are 1-km at best, and thus the cross-track width for geolocations is 11 pixels. Along-track, all MODIS pixels from the original product are preserved. In the standard product, the 250 meter MODIS Level 1B data set contains calibrated and geolocated at-aperture radiances for 2 discrete bands located in the 0.62 to 0.88 micron region of the electromagnetic spectrum. These data are generated from the MODIS Level 1A scans of raw radiance and in the process converted to geophysical units of W/(m^2 um sr). In addition, the Earth Bi-directional Reflectance Distribution Function (BRDF) may be determined for these solar reflective bands through knowledge of the solar irradiance (e.g., determined from MODIS solar diffuser data, and from the target illumination geometry). Additional data are provided including quality flags, error estimates and calibration data. Channel locations for the MODIS 250 meter data are as follows: Band Center Wavelength (um) Primary Use -------------------------- ----------- 1 0.620 - 0.670 Land/Cloud Boundaries 2 0.841 - 0.876 Land/Cloud Boundaries (The shortname for this product is MAC02QS0).

OCO-2 Level 1B calibrated, geolocated calibration spectra, Retrospective Processing V10r (OCO2_L1B_Calibration) at GES DISC

Version 10r is the current version of the data set. Older versions will no longer be available and are superseded by Version 10r. Version 8r is the current version of the data set. Version 7r has been superseded by Version 8r. The Orbiting Carbon Observatory is the first NASA missiondesigned to collect space-based measurements of atmospheric carbon dioxidewith the precision, resolution, and coverage needed to characterize theprocesses controlling its buildup in the atmosphere. The OCO-2 project uses the LEOStar-2 spacecraft that carries a single instrument. It incorporates three high-resolution spectrometers that make coincident measurements ofreflected sunlight in the near-infrared CO2 near 1.61 and 2.06 micrometers and inmolecular oxygen (O2) A-Band at 0.76 micrometers. The three spectrometers have different characteristics and are calibrated independently. Their raw data numbers (DN) are delivered correlated in time tothe Level 1B process as Level 1A products. Each band has 1016 spectralelements, although some are masked out in the L2 retrieval.This L1B product results from calibration mode measurements (e.g., Lunar,Solar, Dark observations), and thus it differs from the OCO2_L1B_Science(L1bSc) product. The differences in the product formats are only in the geolocation information provided. Whereas the L1bSc products report geolocation data for each sounding, calibration products report the directionof the boresight vector.This is the retrospective processing where the calibration data is estimated from the full timeseries of data (before, during, and after the measurements), and is expected to be of slightly higher quality.

MODIS/Aqua Near Real Time (NRT) Calibrated Radiances 5-Min L1B Swath 500m

The 500 meter MODIS Level 1B Near Real Time (NRT) data set contains calibrated and geolocated at-aperture radiances for 7 discrete bands located in the 0.45 to 2.20 micron region of the electromagnetic spectrum. These data are generated from the MODIS Level 1A scans of raw radiance and in the process converted to geophysical units of W/(m^2 um sr). In addition, the Earth Bi-directional Reflectance Distribution Function (BRDF) may be determined for these solar reflective bands through knowledge of the solar irradiance (e.g., determined from MODIS solar diffuser data, and from the target illumination geometry). Additional data are provided including quality flags, error estimates and calibration data. Visible, shortwave infrared, and near infrared measurements are only made during the daytime, while radiances for the thermal infrared region (bands 20-25, 27-36) are measured continuously. Channel locations for the MODIS 500 meter data are as follows: Band Center Wavelength (um) Primary Use ---- ---------------------- ----------- 1 0.620 - 0.670 Land/Cloud Boundaries 2 0.841 - 0.876 Land/Cloud Boundaries 3 0.459 - 0.479 Land/Cloud Properties 4 0.545 - 0.565 Land/Cloud Properties 5 1.230 - 1.250 Land/Cloud Properties 6 1.628 - 1.652 Land/Cloud Properties 7 2.105 - 2.155 Land/Cloud Properties Channels 1 and 2 have 250 m resolution, channels 3 through 7 have 500 m resolution. However, for the MODIS L1B 500 m product, the 250 m band radiance data and their associated uncertainties have been aggregated to 500 m resolution. Thus the entire channel data set has been co-registered to the same spatial scale in the 500 m product. Separate L1B products are available for the 250 m resolution channels (MYD02QKM) and 1 km resolution channels (MYD021KM). For the latter product, the 250 m and 500 m channel data (bands 1 through 7) have been aggregated into equivalent 1 km pixel values. Spatial resolution for pixels at nadir is 500 km, degrading to 2.4 km in the along-scan direction at the scan extremes. However, thanks to the overlapping of consecutive swaths and respectively pixels there, the resulting resolution at the scan extremes is about 1 km. A 55 degree scanning pattern at the EOS orbit of 705 km results in a 2330 km orbital swath width and provides global coverage every one to two days. A single MODIS Level 1B 500 m granule will contain a scene built from 203 scans sampled 2708 times in the cross-track direction, corresponding to approximately 5 minutes worth of data; thus 288 granules will be produced per day. Since an individual MODIS scan will contain 20 along-track spatial elements for the 500 m channels, the scene will be composed of (2708 x 4060) pixels, resulting in a spatial coverage of (2330 km x 2040 km). Due to the MODIS scan geometry, there will be increasing scan overlap beyond about 20 degrees scan angle. To summarize, the MODIS L1B 500 m data product consists of: 1. Calibrated radiances, uncertainties and number of samples for (2) 250 m reflected solar bands aggregated to 500 m resolution 2. Calibrated radiances and uncertainties for (5) 500 m reflected solar bands 3. Geolocation for 1km pixels, that must be interpolated to get 500 m pixel locations. For the relationship of 1km pixels to 500m pixels, see the Geolocation ATBD http://modis.gsfc.nasa.gov/data/atbd/atbd_mod28_v3.pdf . 4. Calibration data for all channels (scale and offset) 5. Comprehensive set of file-level metadata summarizing the spatial, temporal and parameter attributes of the data, as well as auxiliary information pertaining to instrument status and data quality characterization The MODIS L1B 500 m data are stored in the Earth Observing System Hierarchical Data Format (HDF-EOS) which is an extension of HDF as developed by the National Center for Supercomputer Applications (NCSA) at the University of Illinois. A typical file size will be approximately 170 MB. Environmental information derived from MODIS L1B measurements will offer a comprehensive and unprecedented look at terrestrial, atmospheric, and ocean phenomenology for a wide and diverse community of users throughout the world. The Shortname for this product is MYD02HKM

OCO-2 Level 1B calibrated, geolocated calibration spectra, Retrospective Processing V11r (OCO2_L1B_Calibration) at GES DISC

Version 11r is the current version of the data set. Older versions will no longer be available and are superseded by Version 11r. The Orbiting Carbon Observatory is the first NASA missiondesigned to collect space-based measurements of atmospheric carbon dioxidewith the precision, resolution, and coverage needed to characterize theprocesses controlling its buildup in the atmosphere. The OCO-2 project uses the LEOStar-2 spacecraft that carries a single instrument. It incorporates three high-resolution spectrometers that make coincident measurements ofreflected sunlight in the near-infrared CO2 near 1.61 and 2.06 micrometers and inmolecular oxygen (O2) A-Band at 0.76 micrometers. The three spectrometers have different characteristics and are calibrated independently. Their raw data numbers (DN) are delivered correlated in time tothe Level 1B process as Level 1A products. Each band has 1016 spectralelements, although some are masked out in the L2 retrieval.This L1B product results from calibration mode measurements (e.g., Lunar,Solar, Dark observations), and thus it differs from the OCO2_L1B_Science(L1bSc) product. The differences in the product formats are only in the geolocation information provided. Whereas the L1bSc products report geolocation data for each sounding, calibration products report the directionof the boresight vector.This is the retrospective processing where the calibration data is estimated from the full timeseries of data (before, during, and after the measurements), and is expected to be of slightly higher quality.

CEOS Cal Val Test Site - Libya 1 - Pseudo-Invariant Calibration Site (PICS)

On the background of these requirements for sensor calibration, intercalibration and product validation, the subgroup on Calibration and Validation of the Committee on Earth Observing System (CEOS) formulated the following recommendation during the plenary session held in China at the end of 2004, with the goal of setting-up and operating an internet based system to provide sensor data, protocols and guidelines for these purposes: Background: Reference Datasets are required to support the understanding of climate change and quality assure operational services by Earth Observing satellites. The data from different sensors and the resulting synergistic data products require a high level of accuracy that can only be obtained through continuous traceable calibration and validation activities. Requirement: Initiate an activity to document a reference methodology to predict Top of Atmosphere (TOA) radiance for which currently flying and planned wide swath sensors can be intercompared, i.e. define a standard for traceability. Also create and maintain a fully accessible web page containing, on an instrument basis, links to all instrument characteristics needed for intercomparisons as specified above, ideally in a common format. In addition, create and maintain a database (e.g. SADE) of instrument data for specific vicarious calibration sites, including site characteristics, in a common format. Each agency is responsible for providing data for their instruments in this common format. Recommendation : The required activities described above should be supported for an implementation period of two years and a maintenance period over two subsequent years. The CEOS should encourage a member agency to accept the lead role in supporting this activity. CEOS should request all member agencies to support this activity by providing appropriate information and data in a timely manner. Pseudo-Invariant Calibration Sites (PICS): Libya 4 is one of six CEOS reference Pseudo-Invariant Calibration Sites (PICS) that are CEOS Reference Test Sites. Besides the nominally good site characteristics (temporal stability, uniformity, homogeneity, etc.), these six PICS were selected by also taking into account their heritage and the large number of datasets from multiple instruments that already existed in the EO archives and the long history of characterization performed over these sites. The PICS have high reflectance and are usually made up of sand dunes with climatologically low aerosol loading and practically no vegetation. Consequently, these PICS can be used to evaluate the long-term stability of instrument and facilitate inter-comparison of multiple instruments.

OCO-2 Level 1A collated, parsed, science or calibration data, Retrospective Processing V11r (OCO2_L1aIn_Sample) at GES DISC

Version 11r is the current version of the data set. Older versions will no longer be available and are superseded by Version 11r. The Orbiting Carbon Observatory is the first NASA mission designed to collect space-based measurements of atmospheric carbon dioxide with the precision, resolution, and coverage needed to characterize the processes controlling its buildup in the atmosphere. The OCO-2 project uses the LEOStar-2 spacecraft that carries a single instrument. It incorporates three high-resolution spectrometers that make coincident measurements of reflected sunlight in the near-infrared CO2 near 1.61 and 2.06 micrometers and in molecular oxygen (O2) A-Band at 0.76 micrometers. The three spectrometers have different characteristics and are calibrated independently. Their raw data numbers (DN) are delivered correlated in time to the Level 1B process as Level 1A products. Each band has 1016 spectral elements, although some are masked out in the L2 retrieval.This product is the input to the Level 1B process. It is depacketized raw data formatted into a standard granularity with calibrated engineering data (for both science and calibration observations), in the Sample Mode of operation.This is the retrospective processing where the calibration data is estimated from the full timeseries of data (before, during, and after the measurements), and is expected to be of slightly higher quality.

Optical Sediment Trap Calibration on the New England coast

Measurements from the Opt_Sed_Trap_Cal (Optical Sediment Trap Calibration) project off the New England coast.

MODIS/Aqua Level 1B Subsampled Calibrated Radiance 5Km - NRT

This Near Real Time (NRT) data type (MYD02SSH) is a subsample from the MODIS Level 1B 1-km data. Every fifth pixel is taken from the MYD021KM product and written out to MYD02SSH. The subsampling starts at the third frame, and at the third line. Here, "frame" and "line" are naming conventions for pixels along and across the scan, respectively. Since MYD02SSH is a subsampled Level 1B , many things from the Level 1B documentation apply as well. That is, the MYD02SSH data productcontains calibrated and geolocated at-aperture radiances for 36 bands generated from MODIS Level 1A scans of raw radiance (MOD 01). The radiance units are in W/(m ^2 um sr). Additional data are provided including quality flags, error estimates and calibration data. Visible, shortwave infrared (SWIR), and Near Infrared (NIR) measurements are made during daytime only, while radiances for Thermal Infrared (TIR) are measured continuously.As it's parent, the MYD02SSH is in HDF-EOS format, and all metadata structures and names are preserved for better convenience. However, some relevant changes are made where appropriate, e.g. the dimension mappings are updated to reflect the new one-to-one correspondance between the data and geolocations. The latter is one of the most important differences: in the MYD02SSH, there is no offset between data and geolocation pixels. The spatial coverage is almost similar to that from MYD021KM (nominally it is 2330 by 2030 km, cross-track by along-track, respectively). The MYD02SSH is produced continuously, and thus the processing provides 2-day repeat observations of the Earth with a repeat orbitpattern every 16 days.The shortname for this product is MYD02SSH

MODIS/Terra Near Real Time (NRT) Calibrated Radiances 5-Min L1B Swath 250m

The 250 meter MODIS Level 1B Near Real Time (NRT) data set contains calibrated and geolocated at-aperture radiances for 2 discrete bands located in the 0.62 to 0.88 micron region of the electromagnetic spectrum. These data are generated from the MODIS Level 1A scans of raw radiance and in the process converted to geophysical units of W / (m^2 um sr). In addition, the Earth Bi-directional Reflectance Distribution Function (BRDF) may be determined for these solar reflective bands through knowledge of the solar irradiance (e.g., determined from MODIS solar diffuser data, and from the target illumination geometry). Additional data are provided including quality flags, error estimates and calibration data. Channel locations for the MODIS 250 meter data are as follows: Band Center Wavelength (um) Primary Use ---- ---------------------- ----------- 1 0.620 - 0.670 Land/Cloud Boundaries 2 0.841 - 0.876 Land/Cloud Boundaries Separate L1B products are available for the five 500 m resolution channels (MOD02HKM) and the twenty-nine 1 km resolution channels (MOD021KM). For the 500 m product, there are actually seven channels available since the data from the two 250 m channels have been aggregated to 500 m resolution. Similarly, for the 1 km product, all 36 MODIS channels are available since the data from the two 250 m and five 500 m channels have been aggregated into equivalent 1 km pixel values. Spatial resolution for pixels at nadir is 250 m, degrading to 1.2 km in the along-scan direction and 0.5 km in the along-track direction for pixels located at the scan extremes. A 55 degree scanning pattern at the EOS orbit of 705 km results in a 2330 km orbital swath width and provides global coverage every one to two days. A single MODIS Level 1B 250 m granule will contain a scene built from 203 scans sampled 5416 times in the cross-track direction, corresponding to approximately 5 minutes worth of data; thus 288 granules will be produced per day. Since an individual MODIS scan will contain 40 along-track spatial elements for the 250 m channels, the scene will be composed of (5416 x 8120) pixels, resulting in a spatial coverage of (2330 km x 2040 km). Due to the MODIS scan geometry, there will be increasing scan overlap beyond about 17 degrees scan angle. To summarize, the MODIS L1B 250 m data product consists of: 1. Calibrated radiances and uncertainties for (2) 250 m reflected solar bands 2. Subsampled geolocation at every 4th 250 m pixel across and along track, i.e., a geolocation point every kilometer 3. Satellite and solar angles subsampled at the above frequency 4. Calibration data for all channels (scale and offset) 5. Comprehensive set of file-level metadata summarizing the spatial, temporal and parameter attributes of the data, as well as auxiliary information pertaining to instrument status and data quality characterization The MODIS L1B 250 m data are stored in the Earth Observing System Hierarchical Data Format (HDF-EOS) which is an extension of HDF as developed by the National Center for Supercomputer Applications (NCSA) at the University of Illinois. A typical file size will be approximately 170 MB. Environmental information derived from MODIS L1B measurements will offer a comprehensive and unprecedented look at terrestrial, atmospheric, and ocean phenomenology for a wide and diverse community of users throughout the world. The Shortname for this product is MOD02QKM