The International Radio Occultation Working Group (IROWG) community has recently proposed a collaborative effort to explore the impact of RO observations:
Radio Occultation Modeling Experiment (ROMEX)
ROMEX seeks to quantify the benefit of increasing the quantity of RO observations using additional observations unavailable to weather centers for their real-time operational systems. The IROWG community has gained approval from their respective institutions to perform data assimilation experiments with additional RO measurements over the designated period.

Dr. Richard Anthes first introduced the effort concept in May 2022, responding to questions from NOAA for input on future RO needs. The resulting discussion led to a proposal for ROMEX, which the IROWG endorsed in September 2022 (IROWG-9).
The experiment results will guide the CGMS partners to answer pressing technical and programmatic questions facing the numerical weather prediction (NWP) community. This will help inform near- and long-term strategies for RO missions and acquisitions by all CGMS partners.
ROMEX white paper
The full ROMEX white paper (pdf) can be found here.
ROMEX Data Terms and Conditions:
If you want to participate in ROMEX, please sign this document and return it to the steering committee.
We accept signatures by an organization or an individual. If an organization signs the letter, please indicate the POC (point of contact) for this organization. This POC will be responsible for receiving the password for the data FTP later. Also, this person will be contacted if there is a violation of the Terms and Conditions during ROMEX. If no POC is identified explicitly, we’ll get the person who sent in the signature.
ROMEX Data Providers and Users
The list will only include the organizations who have signed the Data License Letter (for data providers only) or Terms and Conditions (for data users. See above). If you want to participate in this effort or have any questions, please get in touch with the steering committee.
Participating organizations:
CMA, CWA (formerly CWB), DMI, DWD, ECCC, ECMWF, IEEC, Meteo France, NRL, NSSC/CAS, Tianmu, Spire, UCAR, UK MetOffice, NASA, Yunyao, PlanetIQ
Data Providers:
EUMETSAT, GeoOptics, NASA/Spire, NOAA, Tianmu, PlanetIQ, UCAR, Yunyao
ROMEX Data Server (coming soon)
ROMSAF will provide a password-protected service to contain the ROMEX data. Once the signed data Terms and Conditions are received, the user will receive a notification on accessing the data server. We’ll send an announcement once this is ready.
Upcoming ROMEX events/meetings
The ROMEX schedule/planned meetings can be found here.
ROMEX Announcement
ROMEX announcement can be found here.
Contact the ROMEX steering committee (RSC)
Questions or requests for information can be addressed to any RSC members.
The members are:
- Richard Anthes: anthes@ucar.edu
- Hui Shao: huishao@ucar.edu
- Christian Marquardt: christian.marquardt@eumetsat.int
- Benjamin Ruston: benr@ucar.edu