PACE Particulate Backscattering March 2024 – present (8 Day Average)

Particulate backscattering coefficient at 442 nanometers (bbp (442)) from the NASA Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) Ocean Color Instrument (OCI). This bbp (442) data layer provides a proxy of water clarity overall as well as an estimate of suspended particulate constituents present in the water. bbp (442) is provided as global, 8-day averages mapped to a standard, equal-angle, latitude-longitude grid of approximately 0.04 degrees, or 4 kilometers (km) at the equator. Pixels with no data values are masked (excluded) due to presence of land, cloud cover, or other features marked by quality control flags as described below. Data Layer Summary Name, units Particulate Backscattering at 442 nm [m-1] Backscattering coefficient of suspended particulate material at 442 nm in units of inverse meters (m-1) Spatial resolution 4 km2 Level-3, mapped to standard grid, global coverage Time Resolution 8 day average Each pixel represents an average of the valid, daily values observed within that grid element during the 8-day interval (approx 1 week). Note: 8 day average data layer is calculated from daily, "refined" (archive-quality) Level 3 PACE bbp (442) products, which are available at NASA Earthdata via this link in NetCDF format as part of the Inherent Optical Properties (IOP) suite. NASA Earthdata account required to download. Data Version Version 3.2 Data versions change as improved calibration, validation, algorithm refinements, etc are applied over time. See Version 3.2 Release Notes for details. Latency ̃1 month This imagery service provides “refined” (archive-quality) PACE data products from March 2024-present, which have an approx 1 month latency. Note: Lower latency “near real time (NRT)” Level 3 PACE bbp (442) data are available at NASA Earthdata via this link in NetCDF format as part of the Inherent Optical Properties (IOP) NRT suite. Latency typically account required to download. What can I do with this layer? The bbp (442) data layer supports water-type classification, water-clarity assessment, biogeochemical studies, and forward/adjoint radiative-transfer applications. As an inherent optical property (IOP, described in background information below), bbp (442) is more suitable for cross-sensor comparisons than apparent optical property (AOP) measurements, which vary with solar conditions at the time of measurement. The time (8 day average) and space (4 km2) resolution of this data layer enables weekly to seasonal and annual insight at sub-regional to global scales. What should I know about the data? Data Status (Maturity): This product is provisional, which means that product results have been reviewed and are in family with heritage data products or other basis of expectation, but have not yet been extensively validated and so may still contain significant errors. Data layer is sufficient for qualitative determinations of product fitness-for-purpose, for testing by operational users, and may be suitable for scientific publication. Data Masking: These products are Level 3, globally-binned products from NASA’s Ocean Biology Processing Group (OBPG), which by default are masked (pixel data value is set to null, or no data) according to a standard set of quality control parameters. For a list of these parameters, see the third column of the table included here: https://oceancolor.gsfc.nasa.gov/resources/atbd/ocl2flags/. Application of bbp (442) in varied water types: The Generalized Inherent Optical Properties framework in its default algorithm configuration (GIOP-DC; Werdell et al. 2013) used to derive bbp (442) was developed to maximize global performance. End users are advised to carefully consider the validity of retrievals in extreme conditions such as highly turbid, optically shallow, and inland/freshwater systems where values may carry higher uncertainty. Algorithm Theoretical Basis Document (ATBD): See ATBD for algorithm details including scientific theory, calculations, etc. at DOI 10.5067/ZGBW3QECROJ2. Where do I go with further questions? Visit NASA’s Earthdata Forum where users can post questions that are answered by the personnel working at NASA with the PACE mission and/or the Ocean Biology Distributed Active Archive Center (OB.DAAC) that processes and distributes PACE data. First, follow this link to view only “PACE” and “OBDAAC” tagged questions on the Earthdata Forum. Then search and read through previous posts for your question. If it has not yet been asked please post your question in the Forum and be sure "PACE" and "OBDAAC" filter tags are applied. Mission and Product Background PACE Mission Overview: Launched in February 2024, NASA’s Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) observatory uniquely provides near-daily, hyperspectral coverage of Earth’s surface, plus hyperspectral and hyperangular polarimetry. PACE is a comprehensive Earth System mission, delivering all new, space-based information on the health and diversity of aquatic and terrestrial life (algae, plants), aerosol properties & modes (e.g. smoke, dust), cloud types, and more. The Ocean Color Instrument (OCI), PACE's primary sensor, is a hyperspectral (5 nm resolution) imaging spectrometer that measures properties of light from the ultraviolet (UV, 340 nm) through visible and near infrared (NIR, 895 nm) portions of the electromagnetic spectrum in 1.25 to 2.5 nm steps, plus 7 shortwave infrared (SWIR) bands (Werdell et al. 2019). Observations from OCI are moderate spatial resolution (1.2 km2), enabling a relatively frequent revisit time of 1-2 days. This combination of continuous, global coverage and spectral capabilities is unmatched by any other satellite platform, public or private. PACE benefits society by expanding our foundational knowledge of Earth and enabling novel, space-based science and applications tools across water resources (e.g. fisheries), air quality, land monitoring & management, and more. The Ocean Color Instrument (OCI), PACE’s primary sensor, is a hyperspectral (5 nm resolution) imaging spectrometer that measures properties of light from the ultraviolet (UV, 340 nm) through visible and near infrared (NIR, 895 nm) portions of the electromagnetic spectrum, plus 7 shortwave infrared (SWIR) bands (Werdell et al. 2019). Observations from OCI are moderate spatial resolution (1.2 km2), enabling a relatively frequent revisit time of 1-2 days. This combination of continuous, global coverage and spectral capabilities is unmatched by any other satellite platform, public or private. PACE benefits society by expanding our foundational knowledge of Earth and enabling novel, space-based science and applications tools across water resources (e.g. fisheries), air quality, land monitoring & management, and more. How is bbp (442) calculated and what does it represent? Inherent optical properties (IOPs; spectral absorption and backscattering coefficients) help us understand how different wavelengths (colors) of light are scattered and absorbed by materials present in natural waters such as lakes, coastal waters, and the ocean. Unlike apparent optical properties (AOPs), IOPs are independent of the surrounding light field or viewing geometry. The different constituents in natural waters - including the water itself, phytoplankton, dissolved matter, and non-algal particulate matter - absorb and scatter light in different ways due to factors such as shape, size, and pigmentation. The types and relative concentrations of constituent matter drive the character of the light reflected from the water making IOPs key parameters in understanding marine biogeochemical processes and the characteristics of the under-water light field. The current default configuration of the Generalized Inherent Optical Properties (GIOP-DC; Werdell et al. 2013) algorithm used to derive this data layer is based on a scientific understanding of the physics of light in water, relating IOPs to the light reflected from the ocean that is observed by space-borne sensors. The GIOP-DC input variables include spectral remote sensing reflectance values and biophysical environmental conditions, and returned variables include 7 atmospherically corrected spectral IOPs of near surface waters and their uncertanty values (see ATBD for details). Of these GIOP-DC output variables, the coefficients of both particulate bacscattering and non-algal particulate plus colored dissolved organic matter at one wavelength of 442 nm (bbp (455) and adg (442), respectively, in units of meters-1) are provided here as data layers to utilize as measures of the absorption and scattering properties of a given water body. What other PACE data layers are available? This data layer is 1 of 11 PACE products initially selected for the Living Atlas catalog from the mission’s comprehensive aquatic, atmospheric, and terrestrial product catalog. Click here to view all 11 PACE Living Atlas imagery services. Global, hyperspectral remote sensing reflectance observations from OCI with over 250 spectral bands, and used to derive many of PACE's aquatic products, are available to download in NetCDF format from NASA Earthdata as Level 3, mapped data with 4 km2 resolution or as Level 2 granules at unprojected, native spatial resolution (1.2 km2). To learn more about obtaining PACE data from NASA, first learn about PACE data access here, next decide which product(s) you would like to use, then go to NASA Earthdata to find your product(s) of interest in NetCDF format, which can be downloaded and then imported into ArcGIS. To learn about using Earthdata Search to narrow your data product selection, watch this tutorial. An Earthdata account is needed to download data from NASA, sign up here. How can I stay up to date with the PACE mission? Join the PACE Community for mission news, events, new product release announcements, and to receive our newsletters. Would you like to see imagery services for more PACE products? Please let us know here. References: McKinna, L. & Werdell, J., authors. (2024) Algorithm theoretical basis document: Inherent Optical Properties, Version 1.0. NASA Goddard Space Flight Center, Ocean Ecology Lab. https://doi.org/10.5067/JCQB8QALDOYD. Werdell, P. J., Franz, B. A., Bailey, S. W., Feldman, G. C., Boss, E., Brando, V. E., Dowell, M. et al. (2013) Generalized ocean color inversion model for retrieving marine inherent optical properties. Applied Optics, 52(10), 2019--2037. https://doi.org/10.1364/AO.52.002019 Werdell, P. J. et al. (2019) The Plankton, Aerosol, Cloud, Ocean Ecosystem Mission: Status, Science, Advances. Bulletin of the American Meteorological Society, 100, 1775–1794. https://doi.org/10.1175/BAMS-D-18-0056.1

Absorption coefficient of detrital (non-algal particulate) material and gelbstoff (colored dissolved organic matter) at 442 nanometers (adg (442)) from the NASA Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) Ocean Color Instrument (OCI). This adg (442) data layer provides proxy of water clarity overall as well as an estimate of the optically active dissolved and particulate constituents other than phytoplankton present in the water. adg (442) is provided as global, 8-day averages mapped to a standard, equal-angle, latitude-longitude grid of approximately 0.04 degrees, or 4 kilometers (km) at the equator. Pixels with no data values are masked (excluded) due to presence of land, cloud cover, or other features marked by quality control flags as described below. Data Layer Summary Name, units Absorption of Gelbstoff and Detrital Material at 442nm [m-1] Absorption coefficient of gelbstoff (colored dissolved organic matter) and detritus (non-algal particulate matter) at 442 nanometers, in units of inverse meters (m-1) Spatial resolution 4 km2 Level-3, mapped to standard grid, global coverage Time Resolution 8 day average Each pixel represents an average of the valid, daily values observed within that grid element during the 8-day interval (approx 1 week). Note: 8 day average data layer is calculated from daily, "refined" (archive-quality) Level 3 PACE adg (442) products, which are available at NASA Earthdata via this link in NetCDF format as part of the Inherent Optical Properties (IOP) suite. NASA Earthdata account required to download. Data Version Version 3.2 Data versions change as improved calibration, validation, algorithm refinements, etc are applied over time. See Version 3.2 Release Notes for details. Latency ̃1 month This imagery service provides “refined” (archive-quality) PACE data products from March 2024-present, which have an approx 1 month latency. Note: Lower latency “near real time (NRT)” Level 3 PACE adg (442) data are available at NASA Earthdata via this link in NetCDF format as part of the Inherent Optical Properties (IOP) NRT suite. Latency typically account required to download. What can I do with this layer? The adg (442) data layer supports water-type classification, water-clarity assessment, biogeochemical studies, and forward/adjoint radiative-transfer applications. As an inherent optical property (IOP, described in background information below), adg (442) is more suitable for cross-sensor comparisons than apparent optical property (AOP) measurements, which vary with solar conditions at the time of measurement. The time (8 day average) and space (4 km2) resolution of this data layer enables weekly to seasonal and annual insight at sub-regional to global scales. What should I know about the data? Data Status (Maturity): This product is provisional, which means that product results have been reviewed and are in family with heritage data products or other basis of expectation, but have not yet been extensively validated and so may still contain significant errors. Data layer is sufficient for qualitative determinations of product fitness-for-purpose, for testing by operational users, and may be suitable for scientific publication. Data Masking: These products are Level 3, globally-binned products from NASA’s Ocean Biology Processing Group (OBPG), which by default are masked (pixel data value is set to null, or no data) according to a standard set of quality control parameters. For a list of these parameters, see the third column of the table included here: https://oceancolor.gsfc.nasa.gov/resources/atbd/ocl2flags/. Application of adg (442) in varied water types: The Generalized Inherent Optical Properties framework in its default algorithm configuration (GIOP-DC; Werdell et al. 2013) used to derive adg (442) was developed to maximize global performance. End users are advised to carefully consider the validity of retrievals in extreme conditions such as highly turbid, optically shallow, and inland/freshwater systems where values may carry higher uncertainty. Algorithm Theoretical Basis Document (ATBD): See ATBD for algorithm details including scientific theory, calculations, etc. at DOI 10.5067/ZGBW3QECROJ2. Where do I go with further questions? Visit NASA’s Earthdata Forum where users can post questions that are answered by the personnel working at NASA with the PACE mission and/or the Ocean Biology Distributed Active Archive Center (OB.DAAC) that processes and distributes PACE data. First, follow this link to view only “PACE” and “OBDAAC” tagged questions on the Earthdata Forum. Then search and read through previous posts for your question. If it has not yet been asked please post your question in the Forum and be sure "PACE" and "OBDAAC" filter tags are applied. Mission and Product Background PACE Mission Overview: Launched in February 2024, NASA’s Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) observatory uniquely provides near-daily, hyperspectral coverage of Earth’s surface, plus hyperspectral and hyperangular polarimetry. PACE is a comprehensive Earth System mission, delivering all new, space-based information on the health and diversity of aquatic and terrestrial life (algae, plants), aerosol properties & modes (e.g. smoke, dust), cloud types, and more. The Ocean Color Instrument (OCI), PACE's primary sensor, is a hyperspectral (5 nm resolution) imaging spectrometer that measures properties of light from the ultraviolet (UV, 340 nm) through visible and near infrared (NIR, 895 nm) portions of the electromagnetic spectrum in 1.25 to 2.5 nm steps, plus 7 shortwave infrared (SWIR) bands (Werdell et al. 2019). Observations from OCI are moderate spatial resolution (1.2 km2), enabling a relatively frequent revisit time of 1-2 days. This combination of continuous, global coverage and spectral capabilities is unmatched by any other satellite platform, public or private. PACE benefits society by expanding our foundational knowledge of Earth and enabling novel, space-based science and applications tools across water resources (e.g. fisheries), air quality, land monitoring & management, and more. How is adg (442) calculated and what does it represent? Inherent optical properties (IOPs; spectral absorption and backscattering coefficients) help us understand how different wavelengths (colors) of light are scattered and absorbed by materials present in natural waters such as lakes, coastal waters, and the ocean. Unlike apparent optical properties (AOPs), IOPs are independent of the surrounding light field or viewing geometry. The different constituents in natural waters - including the water itself, phytoplankton, dissolved matter, and non-algal particulate matter - absorb and scatter light in different ways due to factors such as shape, size, and pigmentation. The types and relative concentrations of constituent matter drive the character of the light reflected from the water making IOPs key parameters in understanding marine biogeochemical processes and the characteristics of the under-water light field. The current default configuration of the Generalized Inherent Optical Properties (GIOP-DC; Werdell et al. 2013) algorithm used to derive this data layer is based on a scientific understanding of the physics of light in water, relating IOPs to the sunlight reflected from the ocean that is observed by space-borne sensors. The GIOP-DC input variables include spectral remote sensing reflectance values and biophysical environmental conditions, and returned variables include 7 atmospherically corrected spectral IOPs of near surface waters and their uncertanty values (see ATBD for details). Of these GIOP-DC output variables, the coefficients of both particulate bacscattering and non-algal particulate plus colored dissolved organic matter at one wavelength of 442 nm (bbp (442) and adg (442), respectively, in units of meters-1) are provided here as data layers to utilize as measures of the absorption and scattering properties of a given water body. What other PACE data layers are available? This data layer is 1 of 11 PACE products initially selected for the Living Atlas catalog from the mission’s comprehensive aquatic, atmospheric, and terrestrial product catalog. Click here to view all 11 PACE Living Atlas imagery services. Global, hyperspectral remote sensing reflectance observations from OCI with over 250 spectral bands, and used to derive many of PACE's aquatic products, are available to download in NetCDF format from NASA Earthdata as Level 3, mapped data with 4 km2 resolution or as Level 2 granules at unprojected, native spatial resolution (1.2 km2). To learn more about obtaining PACE data from NASA, first learn about PACE data access here, next decide which product(s) you would like to use, then go to NASA Earthdata to find your product(s) of interest in NetCDF format, which can be downloaded and then imported into ArcGIS. To learn about using Earthdata Search to narrow your data product selection, watch this tutorial. An Earthdata account is needed to download data from NASA, sign up here. How can I stay up to date with the PACE mission? Join the PACE Community for mission news, events, new product release announcements, and to receive our newsletters. Would you like to see imagery services for more PACE products? Please let us know here. References: McKinna, L. & Werdell, J., authors. (2024) Algorithm theoretical basis document: Inherent Optical Properties, Version 1.0. NASA Goddard Space Flight Center, Ocean Ecology Lab. https://doi.org/10.5067/JCQB8QALDOYD. Werdell, P. J., Franz, B. A., Bailey, S. W., Feldman, G. C., Boss, E., Brando, V. E., Dowell, M. et al. (2013) Generalized ocean color inversion model for retrieving marine inherent optical properties. Applied Optics, 52(10), 2019--2037. https://doi.org/10.1364/AO.52.002019 Werdell, P. J. et al. (2019) The Plankton, Aerosol, Cloud, Ocean Ecosystem Mission: Status, Science, Advances. Bulletin of the American Meteorological Society, 100, 1775–1794. https://doi.org/10.1175/BAMS-D-18-0056.1

Absorption coefficient of detrital (non-algal particulate) material and gelbstoff (colored dissolved organic matter) at 442 nanometers (adg (442)) from the NASA Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) Ocean Color Instrument (OCI). This adg (442) data layer provides proxy of water clarity overall as well as an estimate of the optically active dissolved and particulate constituents other than phytoplankton present in the water. adg (442) is provided as global, 8-day averages mapped to a standard, equal-angle, latitude-longitude grid of approximately 0.04 degrees, or 4 kilometers (km) at the equator. Pixels with no data values are masked (excluded) due to presence of land, cloud cover, or other features marked by quality control flags as described below. Data Layer Summary Name, units Absorption of Gelbstoff and Detrital Material at 442nm [m-1] Absorption coefficient of gelbstoff (colored dissolved organic matter) and detritus (non-algal particulate matter) at 442 nanometers, in units of inverse meters (m-1) Spatial resolution 4 km2 Level-3, mapped to standard grid, global coverage Time Resolution 8 day average Each pixel represents an average of the valid, daily values observed within that grid element during the 8-day interval (approx 1 week). Note: 8 day average data layer is calculated from daily, "refined" (archive-quality) Level 3 PACE adg (442) products, which are available at NASA Earthdata via this link in NetCDF format as part of the Inherent Optical Properties (IOP) suite. NASA Earthdata account required to download. Data Version Version 3.2 Data versions change as improved calibration, validation, algorithm refinements, etc are applied over time. See Version 3.2 Release Notes for details. Latency ̃1 month This imagery service provides “refined” (archive-quality) PACE data products from March 2024-present, which have an approx 1 month latency. Note: Lower latency “near real time (NRT)” Level 3 PACE adg (442) data are available at NASA Earthdata via this link in NetCDF format as part of the Inherent Optical Properties (IOP) NRT suite. Latency typically account required to download. What can I do with this layer? The adg (442) data layer supports water-type classification, water-clarity assessment, biogeochemical studies, and forward/adjoint radiative-transfer applications. As an inherent optical property (IOP, described in background information below), adg (442) is more suitable for cross-sensor comparisons than apparent optical property (AOP) measurements, which vary with solar conditions at the time of measurement. The time (8 day average) and space (4 km2) resolution of this data layer enables weekly to seasonal and annual insight at sub-regional to global scales. What should I know about the data? Data Status (Maturity): This product is provisional, which means that product results have been reviewed and are in family with heritage data products or other basis of expectation, but have not yet been extensively validated and so may still contain significant errors. Data layer is sufficient for qualitative determinations of product fitness-for-purpose, for testing by operational users, and may be suitable for scientific publication. Data Masking: These products are Level 3, globally-binned products from NASA’s Ocean Biology Processing Group (OBPG), which by default are masked (pixel data value is set to null, or no data) according to a standard set of quality control parameters. For a list of these parameters, see the third column of the table included here: https://oceancolor.gsfc.nasa.gov/resources/atbd/ocl2flags/. Application of adg (442) in varied water types: The Generalized Inherent Optical Properties framework in its default algorithm configuration (GIOP-DC; Werdell et al. 2013) used to derive adg (442) was developed to maximize global performance. End users are advised to carefully consider the validity of retrievals in extreme conditions such as highly turbid, optically shallow, and inland/freshwater systems where values may carry higher uncertainty. Algorithm Theoretical Basis Document (ATBD): See ATBD for algorithm details including scientific theory, calculations, etc. at DOI 10.5067/ZGBW3QECROJ2. Where do I go with further questions? Visit NASA’s Earthdata Forum where users can post questions that are answered by the personnel working at NASA with the PACE mission and/or the Ocean Biology Distributed Active Archive Center (OB.DAAC) that processes and distributes PACE data. First, follow this link to view only “PACE” and “OBDAAC” tagged questions on the Earthdata Forum. Then search and read through previous posts for your question. If it has not yet been asked please post your question in the Forum and be sure "PACE" and "OBDAAC" filter tags are applied. Mission and Product Background PACE Mission Overview: Launched in February 2024, NASA’s Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) observatory uniquely provides near-daily, hyperspectral coverage of Earth’s surface, plus hyperspectral and hyperangular polarimetry. PACE is a comprehensive Earth System mission, delivering all new, space-based information on the health and diversity of aquatic and terrestrial life (algae, plants), aerosol properties & modes (e.g. smoke, dust), cloud types, and more. The Ocean Color Instrument (OCI), PACE's primary sensor, is a hyperspectral (5 nm resolution) imaging spectrometer that measures properties of light from the ultraviolet (UV, 340 nm) through visible and near infrared (NIR, 895 nm) portions of the electromagnetic spectrum in 1.25 to 2.5 nm steps, plus 7 shortwave infrared (SWIR) bands (Werdell et al. 2019). Observations from OCI are moderate spatial resolution (1.2 km2), enabling a relatively frequent revisit time of 1-2 days. This combination of continuous, global coverage and spectral capabilities is unmatched by any other satellite platform, public or private. PACE benefits society by expanding our foundational knowledge of Earth and enabling novel, space-based science and applications tools across water resources (e.g. fisheries), air quality, land monitoring & management, and more. How is adg (442) calculated and what does it represent? Inherent optical properties (IOPs; spectral absorption and backscattering coefficients) help us understand how different wavelengths (colors) of light are scattered and absorbed by materials present in natural waters such as lakes, coastal waters, and the ocean. Unlike apparent optical properties (AOPs), IOPs are independent of the surrounding light field or viewing geometry. The different constituents in natural waters - including the water itself, phytoplankton, dissolved matter, and non-algal particulate matter - absorb and scatter light in different ways due to factors such as shape, size, and pigmentation. The types and relative concentrations of constituent matter drive the character of the light reflected from the water making IOPs key parameters in understanding marine biogeochemical processes and the characteristics of the under-water light field. The current default configuration of the Generalized Inherent Optical Properties (GIOP-DC; Werdell et al. 2013) algorithm used to derive this data layer is based on a scientific understanding of the physics of light in water, relating IOPs to the sunlight reflected from the ocean that is observed by space-borne sensors. The GIOP-DC input variables include spectral remote sensing reflectance values and biophysical environmental conditions, and returned variables include 7 atmospherically corrected spectral IOPs of near surface waters and their uncertanty values (see ATBD for details). Of these GIOP-DC output variables, the coefficients of both particulate bacscattering and non-algal particulate plus colored dissolved organic matter at one wavelength of 442 nm (bbp (442) and adg (442), respectively, in units of meters-1) are provided here as data layers to utilize as measures of the absorption and scattering properties of a given water body. What other PACE data layers are available? This data layer is 1 of 11 PACE products initially selected for the Living Atlas catalog from the mission’s comprehensive aquatic, atmospheric, and terrestrial product catalog. Click here to view all 11 PACE Living Atlas imagery services. Global, hyperspectral remote sensing reflectance observations from OCI with over 250 spectral bands, and used to derive many of PACE's aquatic products, are available to download in NetCDF format from NASA Earthdata as Level 3, mapped data with 4 km2 resolution or as Level 2 granules at unprojected, native spatial resolution (1.2 km2). To learn more about obtaining PACE data from NASA, first learn about PACE data access here, next decide which product(s) you would like to use, then go to NASA Earthdata to find your product(s) of interest in NetCDF format, which can be downloaded and then imported into ArcGIS. To learn about using Earthdata Search to narrow your data product selection, watch this tutorial. An Earthdata account is needed to download data from NASA, sign up here. How can I stay up to date with the PACE mission? Join the PACE Community for mission news, events, new product release announcements, and to receive our newsletters. Would you like to see imagery services for more PACE products? Please let us know here. References: McKinna, L. & Werdell, J., authors. (2024) Algorithm theoretical basis document: Inherent Optical Properties, Version 1.0. NASA Goddard Space Flight Center, Ocean Ecology Lab. https://doi.org/10.5067/JCQB8QALDOYD. Werdell, P. J., Franz, B. A., Bailey, S. W., Feldman, G. C., Boss, E., Brando, V. E., Dowell, M. et al. (2013) Generalized ocean color inversion model for retrieving marine inherent optical properties. Applied Optics, 52(10), 2019--2037. https://doi.org/10.1364/AO.52.002019 Werdell, P. J. et al. (2019) The Plankton, Aerosol, Cloud, Ocean Ecosystem Mission: Status, Science, Advances. Bulletin of the American Meteorological Society, 100, 1775–1794. https://doi.org/10.1175/BAMS-D-18-0056.1

Apparent Visible Wavelength (AVW) from the NASA Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) Ocean Color Instrument (OCI). The AVW data product leverages OCI's continuous, hyperspectral set of remote sensing reflectance wavelengths spanning the visible spectrum (from 400-700 nanometers, nm) to calculate AVW in units of nm, a single value describing the dominant color of the water being observed (Vandermeulen et al. 2020; Vandermeulen and Cetinic 2024). AVW is provided as global, 8-day averages mapped to a standard, equal-angle, latitude-longitude grid of approximately 0.04 degrees, or 4 kilometers (km) at the equator. Pixels with no data values are masked (excluded) due to presence of land, cloud cover, or other features marked by quality control flags as described below. Data Layer Summary Name, units Apparent Visible Wavelength [nm] Apparent visible wavelength, a measure of ocean color, in units of nanometers (nm) Spatial resolution 4 km2 Level-3, mapped to standard grid, global coverage Time Resolution 8 day average Each pixel represents an average of the valid, daily values observed within that grid element during the 8-day interval (approx 1 week). Note: 8 day average data layer is calculated from daily, "refined" (archive-quality) Level 3 PACE AVW products, which are available at NASA Earthdata via this link in NetCDF format as part of the Apparent Optical Properties (AOP) suite. NASA Earthdata account required to download. Data Version Version 3.2 Data versions change as improved calibration, validation, algorithm refinements, etc are applied over time. See Version 3.2 Release Notes for details. Latency ̃1 month This imagery service provides “refined” (archive-quality) PACE data products from March 2024-present, which have an approx 1 month latency. Note: Lower latency “near real time (NRT)” Level 3 PACE AVW products are available at NASA Earthdata via this link in NetCDF format as part of the Apparent Optical Properties (AOP) suite. Latency typically account required to download. What can I do with this layer? AVW is simple and intuitive spectral classification tool that enables a more manageable handling of complex spectral information for aquatic science applications (Vandermeulen et al. 2020). Changing values in AVW are a measure of change in the ocean's dominant color: lower AVW values represent more clear water and higher values represent more turbid water. AVW is a useful as an optical water-type index, partitioning a region's ocean observations into types relevant to water quality and marine ecosystem processes. Additionally, AVW can be applied to datasets of varying multi- and hyperspectral resolutions. This provides continuity between PACE AVW and AVW from heritage satellite ocean color sensors (those launched prior to PACE), enabling examination of longer term (up to decadal) trends of AVW in a given region (Vandermeulen et al. 2020; Vandermeulen and Cetinic 2024). The time (8 day average) and space (4 km2) resolution of this data layer supports weekly to seasonal and annual insight at sub-regional to global scales. What should I know about the data? Data Status (Maturity): This product is provisional, which means that product results have been reviewed and are in family with heritage data products or other basis of expectation, but have not yet been extensively validated and so may still contain significant errors. Data layer is sufficient for qualitative determinations of product fitness-for-purpose, for testing by operational users, and may be suitable for scientific publication. Data Masking: These products are Level 3, globally-binned products from NASA’s Ocean Biology Processing Group (OBPG), which by default are masked (pixel data value is set to null, or no data) according to a standard set of quality control parameters. For a list of these parameters, see the third column of the table included here: https://oceancolor.gsfc.nasa.gov/resources/atbd/ocl2flags/. Algorithm Theoretical Basis Document (ATBD): See ATBD for algorithm details including scientific theory, calculations, etc. at DOI 10.5067/KAROCHG01RYJ. Where do I go with further questions? Visit NASA’s Earthdata Forum where users can post questions that are answered by the personnel working at NASA with the PACE mission and/or the Ocean Biology Distributed Active Archive Center (OB.DAAC) that processes and distributes PACE data. First, follow this link to view only “PACE” and “OBDAAC” tagged questions on the Earthdata Forum. Then search and read through previous posts for your question. If it has not yet been asked please post your question in the Forum and be sure "PACE" and "OBDAAC" filter tags are applied. Mission and Product Background PACE Mission Overview: Launched in February 2024, NASA’s Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) observatory uniquely provides near-daily, hyperspectral coverage of Earth’s surface, plus hyperspectral and hyperangular polarimetry. PACE is a comprehensive Earth System mission, delivering all new, space-based information on the health and diversity of aquatic and terrestrial life (algae, plants), aerosol properties & modes (e.g. smoke, dust), cloud types, and more. The Ocean Color Instrument (OCI), PACE's primary sensor, is a hyperspectral (5 nm resolution) imaging spectrometer that measures properties of light from the ultraviolet (UV, 340 nm) through visible and near infrared (NIR, 895 nm) portions of the electromagnetic spectrum in 1.25 to 2.5 nm steps, plus 7 shortwave infrared (SWIR) bands (Werdell et al. 2019). Observations from OCI are moderate spatial resolution (1.2 km2), enabling a relatively frequent revisit time of 1-2 days. This combination of continuous, global coverage and spectral capabilities is unmatched by any other satellite platform, public or private. PACE benefits society by expanding our foundational knowledge of Earth and enabling novel, space-based science and applications tools across water resources (e.g. fisheries), air quality, land monitoring & management, and more. What does AVW represent and how is it calculated? AVW is a one-dimensional geophysical metric that is inherently correlated to ocean color, as defined by the remote sensing reflectance (R(λ)rs) spectral shape across the visible region of the spectrum (400-700 nm; Vandermeulen et al. 2020). R(λ)rs, the AVW algorithm input, is used to calculate the weighted harmonic mean of the wavelengths. Output is an AVW in units of nm, a quantitative descriptor of weighted mean color reflected from the water's surface. PACE AVW spans PACE's continuous hyperspectral R(λ)rs observations across the visible spectrum while AVW from heritage multi-spectral sensors is calculated from their 4-10 available R(λ)rs channels (Vandermeulen and Cetinic 2024). The entire visible spectrum is utilized in the calculation of AVW, affording the opportunity to describe and analyze spectral trends in R(λ)rs in terms of a single variable (Vandermeulen et al. 2020). This simplification allows for streamlined visualisation and monitoring of small changes in apparent color from highly complex optical data. AVW's dimensionality reduction of spectral information is a robust and user-friendly means to describe and analyze R(λ)rs in terms of spatial and temporal trends and variability. Also, AVW can be utilized across heritage and current ocean color sensors, allowing for continuity and long term monitoring of AVW in aquatic ecosystems. What other PACE data layers are available? This data layer is 1 of 11 PACE products initially selected for the Living Atlas catalog from the mission’s comprehensive aquatic, atmospheric, and terrestrial product catalog. Click here to view all 11 PACE Living Atlas imagery services. Global, hyperspectral remote sensing reflectance observations from OCI with over 250 spectral bands, and used to derive many of PACE's aquatic products, are available to download in NetCDF format from NASA Earthdata as Level 3, mapped data with 4 km2 resolution or as Level 2 granules at unprojected, native spatial resolution (no finer than 1.2km2). To learn more about obtaining PACE data from NASA, first learn about PACE data access here, next decide which product(s) you would like to use, then go to NASA Earthdata to find your product(s) of interest in NetCDF format, which can be downloaded and then imported into ArcGIS. To learn about using Earthdata Search to narrow your data product selection, watch this tutorial. An Earthdata account is needed to download data from NASA, sign up here. How can I stay up to date with the PACE mission? Join the PACE Community for mission news, events, new product release announcements, and to receive our newsletters. Would you like to see imagery services for more PACE products? Please let us know here. References: Vandermeulen, R. and Cetinic, I., authors. (2024) Algorithm theoretical basis document: Apparent Visible Wavelength, Version 1.1. NASA Goddard Space Flight Center, Ocean Ecology Lab. https://doi.org/10.5067/KAROCHG01RYJ. Vandermeulen, R. A., Mannino, A., Craig, S. E. & Werdell, P. J. (2020) 150 shades of green: Using the full spectrum of remote sensing reflectance to elucidate color shifts in the ocean. Remote Sensing of Environment, 247, 111900. https://doi.org/10.1016/j.rse.2020.111900 Werdell, P. J. et al. (2019) The Plankton, Aerosol, Cloud, Ocean Ecosystem Mission: Status, Science, Advances. Bulletin of the American Meteorological Society, 100, 1775–1794. https://doi.org/10.1175/BAMS-D-18-0056.1

Apparent Visible Wavelength (AVW) from the NASA Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) Ocean Color Instrument (OCI). The AVW data product leverages OCI's continuous, hyperspectral set of remote sensing reflectance wavelengths spanning the visible spectrum (from 400-700 nanometers, nm) to calculate AVW in units of nm, a single value describing the dominant color of the water being observed (Vandermeulen et al. 2020; Vandermeulen and Cetinic 2024). AVW is provided as global, 8-day averages mapped to a standard, equal-angle, latitude-longitude grid of approximately 0.04 degrees, or 4 kilometers (km) at the equator. Pixels with no data values are masked (excluded) due to presence of land, cloud cover, or other features marked by quality control flags as described below. Data Layer Summary Name, units Apparent Visible Wavelength [nm] Apparent visible wavelength, a measure of ocean color, in units of nanometers (nm) Spatial resolution 4 km2 Level-3, mapped to standard grid, global coverage Time Resolution 8 day average Each pixel represents an average of the valid, daily values observed within that grid element during the 8-day interval (approx 1 week). Note: 8 day average data layer is calculated from daily, "refined" (archive-quality) Level 3 PACE AVW products, which are available at NASA Earthdata via this link in NetCDF format as part of the Apparent Optical Properties (AOP) suite. NASA Earthdata account required to download. Data Version Version 3.2 Data versions change as improved calibration, validation, algorithm refinements, etc are applied over time. See Version 3.2 Release Notes for details. Latency ̃1 month This imagery service provides “refined” (archive-quality) PACE data products from March 2024-present, which have an approx 1 month latency. Note: Lower latency “near real time (NRT)” Level 3 PACE AVW products are available at NASA Earthdata via this link in NetCDF format as part of the Apparent Optical Properties (AOP) suite. Latency typically account required to download. What can I do with this layer? AVW is simple and intuitive spectral classification tool that enables a more manageable handling of complex spectral information for aquatic science applications (Vandermeulen et al. 2020). Changing values in AVW are a measure of change in the ocean's dominant color: lower AVW values represent more clear water and higher values represent more turbid water. AVW is a useful as an optical water-type index, partitioning a region's ocean observations into types relevant to water quality and marine ecosystem processes. Additionally, AVW can be applied to datasets of varying multi- and hyperspectral resolutions. This provides continuity between PACE AVW and AVW from heritage satellite ocean color sensors (those launched prior to PACE), enabling examination of longer term (up to decadal) trends of AVW in a given region (Vandermeulen et al. 2020; Vandermeulen and Cetinic 2024). The time (8 day average) and space (4 km2) resolution of this data layer supports weekly to seasonal and annual insight at sub-regional to global scales. What should I know about the data? Data Status (Maturity): This product is provisional, which means that product results have been reviewed and are in family with heritage data products or other basis of expectation, but have not yet been extensively validated and so may still contain significant errors. Data layer is sufficient for qualitative determinations of product fitness-for-purpose, for testing by operational users, and may be suitable for scientific publication. Data Masking: These products are Level 3, globally-binned products from NASA’s Ocean Biology Processing Group (OBPG), which by default are masked (pixel data value is set to null, or no data) according to a standard set of quality control parameters. For a list of these parameters, see the third column of the table included here: https://oceancolor.gsfc.nasa.gov/resources/atbd/ocl2flags/. Algorithm Theoretical Basis Document (ATBD): See ATBD for algorithm details including scientific theory, calculations, etc. at DOI 10.5067/KAROCHG01RYJ. Where do I go with further questions? Visit NASA’s Earthdata Forum where users can post questions that are answered by the personnel working at NASA with the PACE mission and/or the Ocean Biology Distributed Active Archive Center (OB.DAAC) that processes and distributes PACE data. First, follow this link to view only “PACE” and “OBDAAC” tagged questions on the Earthdata Forum. Then search and read through previous posts for your question. If it has not yet been asked please post your question in the Forum and be sure "PACE" and "OBDAAC" filter tags are applied. Mission and Product Background PACE Mission Overview: Launched in February 2024, NASA’s Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) observatory uniquely provides near-daily, hyperspectral coverage of Earth’s surface, plus hyperspectral and hyperangular polarimetry. PACE is a comprehensive Earth System mission, delivering all new, space-based information on the health and diversity of aquatic and terrestrial life (algae, plants), aerosol properties & modes (e.g. smoke, dust), cloud types, and more. The Ocean Color Instrument (OCI), PACE's primary sensor, is a hyperspectral (5 nm resolution) imaging spectrometer that measures properties of light from the ultraviolet (UV, 340 nm) through visible and near infrared (NIR, 895 nm) portions of the electromagnetic spectrum in 1.25 to 2.5 nm steps, plus 7 shortwave infrared (SWIR) bands (Werdell et al. 2019). Observations from OCI are moderate spatial resolution (1.2 km2), enabling a relatively frequent revisit time of 1-2 days. This combination of continuous, global coverage and spectral capabilities is unmatched by any other satellite platform, public or private. PACE benefits society by expanding our foundational knowledge of Earth and enabling novel, space-based science and applications tools across water resources (e.g. fisheries), air quality, land monitoring & management, and more. What does AVW represent and how is it calculated? AVW is a one-dimensional geophysical metric that is inherently correlated to ocean color, as defined by the remote sensing reflectance (R(λ)rs) spectral shape across the visible region of the spectrum (400-700 nm; Vandermeulen et al. 2020). R(λ)rs, the AVW algorithm input, is used to calculate the weighted harmonic mean of the wavelengths. Output is an AVW in units of nm, a quantitative descriptor of weighted mean color reflected from the water's surface. PACE AVW spans PACE's continuous hyperspectral R(λ)rs observations across the visible spectrum while AVW from heritage multi-spectral sensors is calculated from their 4-10 available R(λ)rs channels (Vandermeulen and Cetinic 2024). The entire visible spectrum is utilized in the calculation of AVW, affording the opportunity to describe and analyze spectral trends in R(λ)rs in terms of a single variable (Vandermeulen et al. 2020). This simplification allows for streamlined visualisation and monitoring of small changes in apparent color from highly complex optical data. AVW's dimensionality reduction of spectral information is a robust and user-friendly means to describe and analyze R(λ)rs in terms of spatial and temporal trends and variability. Also, AVW can be utilized across heritage and current ocean color sensors, allowing for continuity and long term monitoring of AVW in aquatic ecosystems. What other PACE data layers are available? This data layer is 1 of 11 PACE products initially selected for the Living Atlas catalog from the mission’s comprehensive aquatic, atmospheric, and terrestrial product catalog. Click here to view all 11 PACE Living Atlas imagery services. Global, hyperspectral remote sensing reflectance observations from OCI with over 250 spectral bands, and used to derive many of PACE's aquatic products, are available to download in NetCDF format from NASA Earthdata as Level 3, mapped data with 4 km2 resolution or as Level 2 granules at unprojected, native spatial resolution (no finer than 1.2km2). To learn more about obtaining PACE data from NASA, first learn about PACE data access here, next decide which product(s) you would like to use, then go to NASA Earthdata to find your product(s) of interest in NetCDF format, which can be downloaded and then imported into ArcGIS. To learn about using Earthdata Search to narrow your data product selection, watch this tutorial. An Earthdata account is needed to download data from NASA, sign up here. How can I stay up to date with the PACE mission? Join the PACE Community for mission news, events, new product release announcements, and to receive our newsletters. Would you like to see imagery services for more PACE products? Please let us know here. References: Vandermeulen, R. and Cetinic, I., authors. (2024) Algorithm theoretical basis document: Apparent Visible Wavelength, Version 1.1. NASA Goddard Space Flight Center, Ocean Ecology Lab. https://doi.org/10.5067/KAROCHG01RYJ. Vandermeulen, R. A., Mannino, A., Craig, S. E. & Werdell, P. J. (2020) 150 shades of green: Using the full spectrum of remote sensing reflectance to elucidate color shifts in the ocean. Remote Sensing of Environment, 247, 111900. https://doi.org/10.1016/j.rse.2020.111900 Werdell, P. J. et al. (2019) The Plankton, Aerosol, Cloud, Ocean Ecosystem Mission: Status, Science, Advances. Bulletin of the American Meteorological Society, 100, 1775–1794. https://doi.org/10.1175/BAMS-D-18-0056.1

Chlorophyll-a (Chlor_a) data layer from the NASA Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) Ocean Color Instrument (OCI). Chlor_a, a proxy of phytoplankton biomass, is calculated from a multi-spectral algorithm that blends the OC4 band ratio (O'Reilly & Werdell, 2019) and color index (CI) algorithms (Hu et al., 2019). Inputs include remote sensing reflectance (Rrs) values at Rrs(442), Rrs(490), Rrs(410), and Rrs(555) nanometers (nm) and 5 empirically-derived coefficients, see algorithm mathematical theory in section 3.2 of this document for details. Chlor_a layer provided here as global, 8-day averages of surface chlorophyll-a concentration (mg m-3) mapped to a standard, equal-angle, latitude-longitude grid of approximately 0.04 degrees, or 4 kilometers (km) at the equator. Pixels with no data values are masked (excluded) due to presence of land, cloud cover, or other features marked by quality control flags as described below. Data Layer Summary Name, units Chlorophyll-a [mg m-3] Surface chlorophyll-a concentration in milligrams per cubic meter Spatial resolution 4 km2 Level-3, mapped to standard grid, global coverage Time Resolution 8 day average Each pixel represents an average of the valid, daily values observed within that grid element during the 8-day interval (approx 1 week). Note: 8 day average data layer is calculated from daily, "refined" (archive-quality) Level 3 PACE Chlor_a products, which are available at NASA Earthdata via this link in NetCDF format as part of the Biogeochemical Properties (BGC) suite. NASA Earthdata account required to download. Data Version Version 3.2 Data versions change as improved calibration, validation, algorithm refinements, etc are applied over time. See Version 3.2 Release Notes for details. Latency ̃1 month This imagery service provides “refined” (archive-quality) PACE data products from March 2024-present, which have an approx 1 month latency. Note: Lower latency “near real time (NRT)” Level 3 PACE Chlor_a products, which are available at NASA Earthdata via this link in NetCDF format as part of the Biogeochemical Properties (BGC) NRT suite. NASA Earthdata account required to download. What can I do with this layer? As a measure of phytoplankton abundance and distribution in surface waters, Chlor_a supports analysis such as time-series, climatologies, and anomaly detection for ocean ecosystem and fisheries applications, teaching/training, and more. Chlor_a pairs well with other water quality parameters such as sea surface temperature (SST), sea surface height (SSH), and winds for environmental context. The time (8 day average) and space (4 km2) resolution of this data layer enables weekly to seasonal and annual insight at sub-regional to global scales. What should I know about the data? Data Status (Maturity): This product is provisional, which means that product results have been reviewed and are in family with heritage data products or other basis of expectation, but have not yet been extensively validated and so may still contain significant errors. Data layer is sufficient for qualitative determinations of product fitness-for-purpose, for testing by operational users, and may be suitable for scientific publication. Data Masking: These products are Level 3, globally-binned products from NASA’s Ocean Biology Processing Group (OBPG), which by default are masked (pixel data value is set to null, or no data) according to a standard set of quality control parameters. For a list of these parameters, see the third column of the table included here: https://oceancolor.gsfc.nasa.gov/resources/atbd/ocl2flags/. Application of Chlor_a in varied water types: The Chlor_a algorithm was developed in clear, open ocean waters. End users are advised to carefully consider the validity of retrievals in extreme conditions such as highly turbid, optically shallow, and inland/freshwater systems where values may carry higher uncertainty. For example, Chlor_a values may be erroneously elevated in the presence of high sediment and/or colored dissolved organic matter concentrations often found at the land-sea interface. Algorithm documentation, and references therein, provide an overview of uncertainty and error in Chlor_a observations from heritage (missions prior to PACE) satellite ocean color observations. For PACE-specific performance evaluation see PACE Chlor_a compared to ship-based chlorophyll a concentrations, results of ongoing field efforts to evaluate performance of PACE algorithms in waters across the globe. Algorithm Theoretical Basis Document (ATBD): See ATBD for algorithm details including scientific theory, calculations, etc. at DOI 10.5067/JCQB8QALDOYD. Where do I go with further questions? Visit NASA’s Earthdata Forum where users can post questions that are answered by the personnel working at NASA with the PACE mission and/or the Ocean Biology Distributed Active Archive Center (OB.DAAC) that processes and distributes PACE data. First, follow this link to view only “PACE” and “OBDAAC” tagged questions on the Earthdata Forum. Then search and read through previous posts for your question. If it has not yet been asked please post your question in the Forum and be sure "PACE" and "OBDAAC" filter tags are applied. Mission and Product Background PACE Mission Overview: Launched in February 2024, NASA’s Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) observatory uniquely provides near-daily, hyperspectral coverage of Earth’s surface, plus hyperspectral and hyperangular polarimetry. PACE is a comprehensive Earth System mission, delivering all new, space-based information on the health and diversity of aquatic and terrestrial life (algae, plants), aerosol properties & modes (e.g. smoke, dust), cloud types, and more. The Ocean Color Instrument (OCI), PACE's primary sensor, is a hyperspectral (5 nm resolution) imaging spectrometer that measures properties of light from the ultraviolet (UV, 340 nm) through visible and near infrared (NIR, 895 nm) portions of the electromagnetic spectrum in 1.25 to 2.5 nm steps, plus 7 shortwave infrared (SWIR) bands (Werdell et al. 2019). Observations from OCI are moderate spatial resolution (1.2 km2), enabling a relatively frequent revisit time of 1-2 days. This combination of continuous, global coverage and spectral capabilities is unmatched by any other satellite platform, public or private. PACE benefits society by expanding our foundational knowledge of Earth and enabling novel, space-based science and applications tools across water resources (e.g. fisheries), air quality, land monitoring & management, and more. What does Chlor_a represent? Daily, global Chlor_a has been continuously collected by NASA since 1997 utilizing a heritage, multi-band algorithm designed for the open ocean. The Chlor_a algorithm calculates the concentration of a major photosynthetic pigment, chlorophyll a, found within aquatic phytoplankton residing in the sunlit layer of the water column. Phytoplankton are single-celled, photosynthetic organisms that form the bottom levels of the marine and freshwater food webs. Functioning as the “plants” of the aquatic environment, they are an energy source for most life in aquatic ecosystems and also make the ocean an important food source for humans. Nearly all phytoplankton have the photosynthetic pigment chlorophyll a, hence Chlor_a is considered a proxy of the abundance and distribution of the total phytoplankton community. The input data for Chlor_a are satellite measurements of various wavelengths of light exiting the water. Chlorophyll a absorbs blue, green, and red wavelengths differently depending on its concentration. This changes the intensity and color of light exiting the aquatic system, which gives the water its color, and allows relationships to be developed that relate the light detected by the sensor to chlorophyll a concentration. In the past decades, the identification of phytoplankton from satellite remote sensing has been mainly focused on chlorophyll a, and the products have been widely used to represent the phytoplankton biomass in primary productivity estimation and biogeochemical models. What other PACE data layers are available? This data layer is 1 of 11 PACE products initially selected for the Living Atlas catalog from the mission’s comprehensive aquatic, atmospheric, and terrestrial product catalog. Click here to view all 11 PACE Living Atlas imagery services. Global, hyperspectral remote sensing reflectance observations from OCI with over 250 spectral bands, and used to derive many of PACE's aquatic products, are available to download in NetCDF format from NASA Earthdata as Level 3, mapped data with 4 km2 resolution or as Level 2 granules at unprojected, native spatial resolution (no finer than 1.2km2). To learn more about obtaining PACE data from NASA, first learn about PACE data access here, next decide which product(s) you would like to use, then go to NASA Earthdata to find your product(s) of interest in NetCDF format, which can be downloaded and then imported into ArcGIS. To learn about using Earthdata Search to narrow your data product selection, watch this tutorial. An Earthdata account is needed to download data from NASA, sign up here. How can I stay up to date with the PACE mission? Join the PACE Community for mission news, events, new product release announcements, and to receive our newsletters. Would you like to see imagery services for more PACE products? Please let us know here. References: Algorithm Theoretical Basis Document: https://doi.org/10.5067/JCQB8QALDOYD. Hu, C., Feng, L., Lee, Z., Franz, B. A., Bailey, S. W., Werdell, P. J. & Proctor, C. W. (2019). Improving satellite global chlorophyll a data products through algorithm refinement and data recovery. Journal of Geophysical Research: Oceans, 124(3), 1524--1543. https://doi.org/10.1029/2019JC014941 O'Reilly, J. E. & Werdell, P. J. (2019). Chlorophyll algorithms for ocean color sensors - OC4, OC5 & OC6. Remote Sensing of Environment, 229, 32--47. https://doi.org/10.1016/j.rse.2019.04.021 Werdell, P. J. et al. (2019). The Plankton, Aerosol, Cloud, Ocean Ecosystem Mission: Status, Science, Advances. Bulletin of the American Meteorological Society, 100, 1775–1794. https://doi.org/10.1175/BAMS-D-18-0056.1