# COSMIC-2 Radio Occultation Profiles
*data products*

## Specifications
- **level**: L2
- **distributor**: ucar
- **file format**: atmPrf, wetPf2, BUFR, ionPrf
- **access endpoint**: https://data.cosmic.ucar.edu/gnss-ro/cosmic2/nrt/
- **access model**: open
- **licence**: UCAR COSMIC data access
- **cost model summary**: Free internet access through UCAR CDAAC for public research and operational users.
- **primary data portal url**: https://www.cosmic.ucar.edu/what-we-do/cosmic-2/data
- **use cases**: ["Numerical weather prediction assimilation","Climate and atmospheric research","Space-weather monitoring","Radio-occultation retrieval validation"]
- **practical limitations**: ["COSMIC-2 neutral-atmosphere products are profile soundings, not surface imagery.","Operational and post-processed product streams have different latencies.","Electron-density profiles are published as provisional space-weather products."]
- **deployment context**: orbital
- **entity type**: data_product
- **last verified date**: 2026-06-08
- **verified by**: operator
- **claim status**: unclaimed
- **provider**: ucar
- **attributes**: {"level":"L2","distributor":"ucar","file_format":"atmPrf, wetPf2, BUFR, ionPrf","access_endpoint":"https://data.cosmic.ucar.edu/gnss-ro/cosmic2/nrt/","access_model":"open","licence":"UCAR COSMIC data access","cost_model_summary":"Free internet access through UCAR CDAAC for public research and operational users.","primary_data_portal_url":"https://www.cosmic.ucar.edu/what-we-do/cosmic-2/data","use_cases":"[\"Numerical weather prediction assimilation\",\"Climate and atmospheric research\",\"Space-weather monitoring\",\"Radio-occultation retrieval validation\"]","practical_limitations":"[\"COSMIC-2 neutral-atmosphere products are profile soundings, not surface imagery.\",\"Operational and post-processed product streams have different latencies.\",\"Electron-density profiles are published as provisional space-weather products.\"]","deployment_context":"orbital"}
- **relevance**: in-scope

## Editorial
COSMIC-2 Radio Occultation Profiles are UCAR CDAAC data products from the FORMOSAT-7/COSMIC-2 constellation. The product family includes Level 2 neutral-atmosphere profiles in atmPrf, wetPf2, and BUFR forms, with near-real-time operational datasets published daily and records available from October 1, 2019 onward.[^ucar-cosmic2-data]

The profiles serve atmospheric profiling buyers that need vertical sounding data for numerical weather prediction, climate and atmospheric research, and validation of radio-occultation retrieval chains. The product is not surface imagery; its value is the vertical profile of refractivity, temperature, pressure, humidity, bending angle, and related retrieved quantities.[^ucar-cdaac-about][^noaa-cosmic2-archive]

COSMIC-2 also publishes space-weather profile products. UCAR lists Level 2 electron-density profiles as provisional near-real-time space-weather datasets, and NOAA describes COSMIC-2 data use for forecasting models and space-weather monitoring.[^ucar-cosmic2-data][^noaa-cosmic2-archive]

## Compositional position
- atmospheric-profiling (topics) --[topic_capabilities]--> COSMIC-2 Radio Occultation Profiles

## Sources
- [ucar-cosmic2-data] | COSMIC-2 Data, UCAR COSMIC | https://www.cosmic.ucar.edu/what-we-do/cosmic-2/data | tier=operator-datasheet | accessed=2026-06-08
- [ucar-cdaac-about] | CDAAC Description, UCAR COSMIC | https://cdaac-www.cosmic.ucar.edu/cdaac/doc/about.html | tier=operator-engineering | accessed=2026-06-08
- [noaa-cosmic2-archive] | NCEI Archives Data from COSMIC-2 Satellites, NOAA NCEI | https://www.ncei.noaa.gov/news/ncei-archives-cosmic-2-data | tier=agency-doc | accessed=2026-06-08
- [cosmic2-doi] | COSMIC-2 Data Products DOI, UCAR COSMIC | https://doi.org/10.5065/T353-C093 | tier=operator-datasheet | accessed=2026-06-08 | published=2019-10-01

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Source: https://eo-atlas.org/data_products/cosmic-2-radio-occultation-profiles
Maintainer: SpectraWorks B.V. (CC-BY 4.0)