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Cross-track Infrared Sounder (CrIS) Level 2 Earth System Science Profiling Algorithm Ammonia Retrieval Algorithm (ESSPA-NH3) V1 (SNDRSNIL2ESPNH3)

Metadata Updated: December 6, 2023

The objective of this limited edition data collection is to examine the ammonia products generated by the ESSPA (Earth System Science Profiling Algorithm) algorithm from the Cross-track Infrared Sounder (CrIS) instruments. The CrIS instrument used for this product is deployed on board the Suomi National Polar-orbiting Partnership (SNPP) platform and uses the Normal Spectral Resolution (NSR) data. The CrIS instrument is a Fourier transform spectrometer with a total of 1305 NSR infrared sounding channels covering the longwave (655-1095 cm-1), midwave (1210-1750 cm-1), and shortwave (2155-2550 cm-1) spectral regions.

The NH3 L2 ammonia algorithm is based on an AER (Atmospheric and Environmental Research, Inc.) program initially developed to process TES (Tropospheric Emissions Spectrometer) trace gas products. This version runs within the ESSPA software framework: it uses the AER OSS forward model and an optimal estimation approach with a Levenberg-Marquardt algorithm. Temperature and water profiles are obtained from the CLIMCAPS Field of Regard (FOR) products, as are initial guesses for surface temperature and emissivity. The algorithm consists of a two-step sequential retrieval the first step retrieves surface temperature and emissivity and the second step an ammonia profile. The algorithm produces ammonia retrievals on every field of view (FOV) in each FOR.

A level 2 granule has been set as 6 minutes of data, 30 footprints crosstrack by 45 lines along track. There are 240 granules per day, with an orbit repeat cycle of approximately 16 day.

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Metadata Created Date November 12, 2020
Metadata Updated Date December 6, 2023

Metadata Source

Harvested from NASA Data.json

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Additional Metadata

Resource Type Dataset
Metadata Created Date November 12, 2020
Metadata Updated Date December 6, 2023
Identifier C1921638441-GES_DISC
Data First Published 2013-01-01
Language en-US
Data Last Modified 2015-11-01
Category SUOMI-NPP, geospatial
Public Access Level public
Bureau Code 026:00
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Citation Karen Cady-Periera. 2020-08-15. SNDRSNIL2ESPNH3. Version 1. Cross-track Infrared Sounder (CrIS) Level 2 Earth System Science Profiling Algorithm Ammonia Retrieval Algorithm (ESSPA-NH3) V1. Greenbelt, MD, USA. Archived by National Aeronautics and Space Administration, U.S. Government, Goddard Earth Sciences Data and Information Services Center (GES DISC). Digital Science Data.
Creator Karen Cady-Periera
Data Presentation Form Digital Science Data
Graphic Preview File
Harvest Object Id 79369b30-371b-402a-8c28-1466440e6d9c
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL
Metadata Type geospatial
Old Spatial -180.0 -90.0 180.0 90.0
Program Code 026:001
Related Documents,,,,
Release Place Greenbelt, MD, USA
Source Datajson Identifier True
Source Hash a515d22e14e86233845add4e4cebd17479862b126dc3233597c2bd0d2e2a63a5
Source Schema Version 1.1
Temporal 2013-01-01T00:00:00Z/2022-01-17T00:00:00Z

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