SISTER: DESIS L2B Aquatic Pigments 30 m V002

Overview

Description

Generated by the Space-based Imaging Spectroscopy and Thermal pathfindER (SISTER) activity in support of the NASA Earth System Observatory's Surface Biology and Geology (SBG) mission, this dataset utilizes existing airborne and spaceborne sources to generate prototype data products spanning terrestrial ecosystems, inland and coastal aquatic ecosystems, hydrology, and geology. The objective of SISTER is to mature many of the workflows, algorithms, and data products envisioned for SBG, lay the groundwork to develop a robust cal/val network, and build a vigorous and expansive user community ahead of launch. This dataset contains experimental Level 2B aquatic pigments (chlorophyll A and phycocyanin concentrations) at 30-m spatial resolution derived from data measured by the DLR Earth Sensing Imaging Spectrometer (DESIS) instrument (https://www.dlr.de/eoc/desktopdefault.aspx/tabid-13614). For the purposes of SISTER, only a handful of scenes have been selected from this mission, with a temporal range between 2020-08-18 and 2022-06-06 and a spatial coverage that is global in scale. DESIS samples spectra over the visible and near-infrared wavelength range from 400 to 1000 nm with a unique spectral resolution of 2.5 nm. The raw DESIS data are first processed to L1B orthocorrected calibrated radiance by the German Aerospace Center (DLR) and then ingested into the SISTER platform for further downstream analysis. This collection was derived from corrected surface reflectance and fractional cover datasets using pre-trained mixture density networks (MDN). MDN weights were derived from Pahlevan et al. (2021) for chlorophyll and O'Shea et al. (2021) for phycocyanin. Prior to model application, reflectance datasets were resampled to model wavelengths and pigment concentration were only estimated on pixels with water fractional cover of greater than 0.9. The output products are provided in GeoTIFF format in units of mg m-3.

Science Keywords

Data Use and Citation

Data Files