Endmember spectra and classified mosaics derived from CRISM mapping data at the south pole of Mars

• Main Author: Cartwright, S. F. A.
• Format: Other/Unknown Material
• Language: English
• Published: Zenodo 2023
• Subjects: Mars; polar; ice; spectroscopy; machine learning; South pole
• Online Access: https://doi.org/10.5281/zenodo.8201616

Overview Multispectral mapping data from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) provide a unique opportunity to characterize south polar ice deposits at higher spectral sampling, spatial resolution, or spatiotemporal coverage than previous work. This new perspective can help to constrain the nature and distribution of different mixtures of CO 2 ice, H 2 O ice, and dust that influence the formation, evolution, and preservation of Mars climate records. We processed 1103 CRISM observations spanning southern summer of six Mars Years through a combination of k -means clustering and random forest classification. Using a set of 12 spectral endmembers directly tied to previous work with high-resolution CRISM targeted data, we made a series of temporally restricted mosaics showing surface spectral variation over time.The endmember set and classified mosaics produced in this work can provide critical context for future studies of the dynamic processes that shape south polar ice deposits. This is follow-on work to a previous study that produced a series of classified maps and a spectral library from CRISM targeted data. That work can be accessed with the following links: Publication: https://doi.org/10.1029/2022JE007372 Repository: https://doi.org/10.5281/zenodo.6960943 Contents The repository contains two .zip files, which can be expanded to access the files described below: classified_mosaics.zip lookup_files SP_CRISM_RF_ColorMap.clr : An ESRI-formatted color map file that can be used to apply the endmember color schemeto random forest-classified maps in ArcGIS (see Symbology settings). Note that for continuity with Cartwright (2022), there are 21 colors in this file, though only endmembers associated with 12 of those colors are present in the classified mosaics. SP_CRISM_RF_ColorMap.txt : A text file that can be loaded into Python as a numpy array and used to generate a matplotlib color ramp. Row indices correspond to endmember numbers (see below) and columns are red, green, and blue values ...