- Announcements - lists.irowg.org

FW: Announcement draft for IROWG - WG III action
by Mannucci, Anthony J (US 3620) 25 Jul '26

25 Jul '26

Dear IROWG colleagues, At the latest Coordination Group for Meteorological Satellites (CGMS) plenary meeting (June 2026), IROWG was notified that CGMS Working Group III (WGIII) tasked IROWG with coordinating a scientific assessment of the impact of the decline in COSMIC-2 radio occultation (RO) observations expected as the constellation ages. The IROWG assessment is to inform the next WGIII Risk Assessment Workshop (24–26 February 2027). FYI, IROWG is under CGMS-WGII (Satellite data and products), while WGIII is the Working Group on Operational Continuity and Contingency Planning. The action reads: Action # Actionee AGN item Description Action feedback/closing document Deadline Status 54.01p_wgiii IROWG WGIII IROWG to assess the impact of the decline in COSMIC data availability, possibly distinguishing between the respective contributions of low- and medium-inclination orbit, and analysing the number of RO required to mitigate the risk 4 June 2026 - A follow-up call will be arranged to better understand how the action item supports agency priorities - IROWG can help coordinate an assessment - The timeline for completing the assessment depends on the detailed plan for conducting the assessment End of 2026 (9th WGIII RAWS: 24-26 Feb 2027) OPEN WGIII has indicated that “we do not need IROWG to weigh in on the potential acquisitions strategies for data, but rather to provide information about what data is needed to maintain capabilities and/or mitigate loss of COSMIC-2.The purpose of the action is for IROWG to provide information to WGIII in advance of the next Risk Assessment to inform WGIII discussion/evaluation of risk posed by degradation/loss of COSMIC-2 and, if needed, discussion of potential contingencies to mitigate loss of COSMIC-2. The questions WGIII would like the IROWG to answer are: 1. From a scientific perspective, what is the minimum number of equatorial (low inclination) RO needed to maintain current performance of operational NWP 2. Define what they mean by low inclination (clarify the orbital characteristics for low inclination so we can be sure we are all talking about the same thing) 3. Identify if there are options to use increases in the number of non-low inclination RO to mitigate the loss of COSMIC 2 and if so, to be specific about how many additional occultations (be specific about number and distribution needed). " The IROWG Co-Chairs will meet with WGIII shortly after IROWG-11 (September 2026) to provide an update on the community's progress. Therefore, we would like to begin gathering relevant information before the workshop and continue the discussion during IROWG-11. We would greatly appreciate hearing from anyone who has: * existing publications, reports, or presentations relevant to the impact of declining COSMIC-2 observations; * ongoing studies or planned work related to this topic; * operational or research experience that could help inform the scientific assessment. We recognize that IROWG is an international scientific working group, and contributions are entirely voluntary. Existing analyses, ongoing work, and expert perspectives are all valuable. If there is sufficient interest, the IROWG Co-Chairs would also be happy to organize an informal community discussion before IROWG-11 to exchange ideas and help facilitate discussion during the workshop. If you have relevant material or would like to contribute to this assessment, please contact the IROWG Co-Chairs at your convenience. Thank you in advance for your help and for supporting this community effort. Best regards, Hui Shao and Uli Foelsche, IROWG Co-Chairs Tony Mannucci, IROWG Rapporteur

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Registration open - OPAC-IROWG 2026
by Ulrich Foelsche 13 Jul '26

13 Jul '26

Dear IROWG, Please register for OPAC-IROWG 2026! ============================================== *Conference registration* is open until *July 31*: https://opacirowg2026.uni-graz.at/en/registration <https://opacirowg2026.uni-graz.at/en/registration> ============================================== Remember: the registration includes lunch and dinner (except Sunday), Get-together party, drinks during the poster session, conference dinner, wine tasting (we don't force you to drink wine - but it is included), ... Thanks to our *sponsors*: https://opacirowg2026.uni-graz.at/en/sponsors/ we have been able to keep the registration fee in a reasonable range, and to reduce the fee for students to 250.- EUR We are currently planning the detailed program, some key points are: Wednesday, Sept. 9: arrival in Seggauberg, Dinner included Thursday, Sept. 10: Workshop starts at 9:00 Get-together dinner in the evening. Friday: Poster session (including drinks) in the evening. Saturday: IROWG Subgroup-meetings, excursion and conference dinner. Sunday is free - you can relax, or prepare your talk ... Monday: Guided wine cellar tour (incl. wine tasting) Wednesday, Sept. 16: Workshop ends around noon, Lunch included If there is urgent need for a side meeting (e.g. on the BUFR format ...), this could happen on Tuesday evening. Please check the workshop page for updates, e.g. regarding travel info: https://opacirowg2026.uni-graz.at/en/info/ We are looking forward to seeing you in Austria in September! Uli Foelsche, on behalf of the organizing committee. U. Foelsche, J. Danzer, M. Schwärz, (WEGC & IPhys UniGraz, AT), OPAC Chairs H. Shao (Naval Research Lab., USA), IROWG Co-Chair A.J. Mannucci (JPL, Pasadena, USA), IROWG-CGMS Rapporteur ===================================================================== -- ************************************************************************** - Ulrich Foelsche - University of Graz - Institute of Physics, Department of Astrophysics and Geophysics (AGP) - Universitaetsplatz 5, 8010 Graz, Austria - Wegener Center for Climate and Global Change (WEGC) - Brandhofgasse 5, 8010 Graz, Austria - Tel: +43-316-380-8590 - E-mail: ulrich.foelsche(a)uni-graz.at **************************************************************************

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Summary of the 3rd PRO Workshop
by Estel Cardellach 07 Jul '26

07 Jul '26

Dear colleagues, We are pleased to announce that the summary report of the *3rd Polarimetric Radio Occultation (PRO) Workshop* has now been published online in the /Journal of the European Meteorological Society/: https://doi.org/10.1016/j.jemets.2026.100045 <https://doi.org/10.1016/j.jemets.2026.100045> The workshop materials, including presentations and additional information, are available through the following link: https://irowg.org/gnss-pro-workshop-gnss-pro-3/ <https://irowg.org/gnss-pro-workshop-gnss-pro-3/?utm_source=chatgpt.com> We thank all participants and contributors for their valuable discussions and continued efforts in advancing Polarimetric Radio Occultation science and applications. Joe, Christian and Estel

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Re: Positions in Atmospheric and Environmental Data Assimilation at ECCC
by Aparicio,Josep (ECCC) 04 Jun '26

04 Jun '26

For diffusion / Pour diffusion: -------------------------------- Positions in Atmospheric and Environmental Data Assimilation Environment and Climate Change Canada (ECCC) Environment and Climate Change Canada (ECCC) is seeking two highly motivated candidate (one postdoctoral fellow and one research scientist) to undertake cutting-edge research in atmospheric and environmental data assimilation. These positions are intended to be offered for an initial three-year term, with the possibility of renewal or transition to a permanent role. The successful candidates will contribute to the advancement of operational numerical weather and environmental prediction (NWEP) systems, with a particular focus on improving the assimilation of atmospheric and environmental observations from both ground-based and space-based remote sensing platforms. The positions are within the Numerical Modelling and Prediction Research Division, where candidates will join a multidisciplinary team of data assimilation and modelling scientists. This team is internationally recognized for its pioneering work in ensemble-based methods (e.g., EnKF, LETKF) and four-dimensional ensemble-variational (4DEnVar) data assimilation techniques. ECCC is particularly interested in candidates with expertise in one or more of the following areas: * Ensemble and/or variational data assimilation methodologies (including coupled data assimilation) * Remote sensing, with emphasis on radiative transfer processes and algorithms * Machine learning and artificial intelligence applications in geosciences * Observation quality control and bias correction techniques Additional assets include: * Programming experience in Fortran, Python (object-oriented programming), and SQLite * Working experience with numerical weather and environmental prediction (NWEP) systems Application Process: Interested candidates are invited to contact Dr. Joel Bedard (joel.bedard(a)ec.gc.ca<mailto:joel.bedard@ec.gc.ca>) Applicants must submit: * A current curriculum vitae, including a list of publications * Information on their country of citizenship/origin * If applicable, their current immigration status in Canada (e.g., work visa, permanent residency, etc.) Candidates who have obtained their PhD within the past three (3) years in a field of natural sciences are also encouraged to apply through the Postdoctoral Research Program (Postdoctoral Research Program - Natural Resources Canada<https://natural-resources.canada.ca/corporate/careers/postdoctoral-research…>), which offers a streamlined hiring process and simplifies requirements for individuals without prior status in Canada. -------------------------------- Postes en assimilation de données atmosphériques et environnementales Environnement et Changement climatique Canada (ECCC) Environnement et Changement climatique Canada (ECCC) est à la recherche de deux candidats hautement motivés (un stagiaire postdoctoral et un chercheur scientifique) afin de mener des travaux de recherche de pointe en assimilation de données atmosphériques et environnementales. Ces postes devraient être offerts sous forme de postes à durée déterminée de trois ans, avec possibilité de renouvellement ou de transition vers un poste permanent. Les candidats retenus contribueront à l’avancement des systèmes opérationnels de prévision numérique du temps et de l’environnement (PNTE), notamment en améliorant l’assimilation des observations atmosphériques et environnementales provenant de plateformes de télédétection terrestres et spatiales. Les postes sont offerts au sein de la division de la recherche en modélisation et prévision numériques, où les candidats intégreront une équipe multidisciplinaire de scientifiques en assimilation de données et en modélisation. Cette équipe est reconnue internationalement pour ses travaux novateurs sur les méthodes basées sur les ensembles (p. ex. EnKF, LETKF) et les techniques d’assimilation variationnelles (4DEnVar). ECCC s’intéresse particulièrement aux candidats possédant une expertise dans un ou plusieurs des domaines suivants : * Méthodes d’assimilation de données ensemblistes et/ou variationnelles (y compris l’assimilation couplée) * Télédétection, avec un accent sur les processus et algorithmes de transfert radiatif * Apprentissage automatique et intelligence artificielle appliqués aux géosciences * Contrôle de la qualité des observations et techniques de correction des biais Atouts supplémentaires : * Expérience en programmation en Fortran, Python (programmation orientée objet) et SQLite * Expérience pratique des systèmes de prévision numérique du temps et de l’environnement (PNTE) Processus de candidature : Les candidats intéressés sont invités à communiquer avec : Dr Joel Bedard (joel.bedard(a)ec.gc.ca<mailto:joel.bedard@ec.gc.ca>) Les candidats doivent soumettre : * Un curriculum vitae à jour, incluant une liste de publications * Des informations sur leur pays de citoyenneté/origine * Le cas échéant, leur statut d’immigration actuel au Canada (p. ex. permis de travail, résidence permanente, etc.) Les candidats ayant obtenu leur doctorat au cours des trois (3) dernières années dans un domaine des sciences naturelles sont également encouragés à présenter leur candidature dans le cadre du Programme de recherche postdoctorale (Programme de recherche postdoctorale - Ressources naturelles Canada<https://ressources-naturelles.canada.ca/organisation/carrieres/programme-re…>), qui offre un processus d’embauche simplifié et facilite les démarches pour les personnes n’ayant pas de statut préalable au Canada. -------------------------------- Joel -- Joel Bédard Directeur de Recherche, Recherche en Assimilation de Données et en Prévision Immédiate Direction Générale des Sciences et de la Technologie - Division de la Recherche en Modélisation et Prévision Numérique Environnement et Changement Climatique Canada / Gouvernement du Canada joel.bedard(a)ec.gc.ca<mailto:joel.bedard@canada.ca> / Tél: +1 514-592-9482 - Research Manager, Data Assimilation and Nowcasting Research Science and Technology Branch – Numerical Modelling and Prediction Research Division Environment and Climate Change Canada / Government of Canada joel.bedard(a)ec.gc.ca<mailto:joel.bedard@ec.gc.ca> / Tél: +1 514-592-9482

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Sentinel-6 B RO NRT BUFR product release on GTS
by Galley, Chad R (US 3620) 22 May '26

22 May '26

Dear NWP centers, The Sentinel-6 project is pleased to announce the release of the Sentinel-6 B RO NRT Levels 1b & 2 BUFR products on GTS starting Thursday, May 21, 2026. BUFR products from the first satellite, Sentinel-6 Michael Freilich (“MF”, also known as “A”), will continue to be made available on GTS. S6-B and S6-MF are currently flying in tandem with a 30-second orbital separation. As a result, the RO measurements from both satellites are closely collocated. The satellites will be in this tandem phase until S6-MF is moved to a different orbit, which will happen no earlier than October 2026 and possibly by January 2027 (TBC). We will follow-up with another announcement when S6-MF has been moved to its new orbit at which point data from both satellites will no longer be collocated. Validation The GNSS-RO instrument has been working nominally on S6-B with antenna beam-forming enabled, producing SNRs comparable to COSMIC-2 setting occultations. Rising occultations have lower SNRs than COSMIC-2 due to the smaller fore-looking RO antenna on the Sentinel-6 satellites. As of this writing, the average number of NRT BUFR products generated per day is about 1100. Comparisons with ECMWF and NCEP models of the retrieved bending angle profiles in the core region around 15-40 km show performance characteristics for both Sentinel-6 satellites that are similar to other validated GNSS-RO missions with a bias less than 0.1% in magnitude. The Sentinel-6 B BUFR products have been assessed by partner NWP centers, which include NOAA, ECMWF, UK Met Office, Météo France, DWD, ECCC, and JCSDA, and were deemed to be of sufficient quality for weather forecasting purposes. NWP partners have recommended their release on GTS for weather forecasting purposes. WMO Routing Headers The abbreviated WMO headers for the products from Sentinel-6 B are: Abbreviated WMO header Source Comments IPXB01 KWBC Sentinel-6 B BUFR product generated from NASA/JPL’s RO primary processor Frequently used IPXB02 KWBC Sentinel-6 B BUFR product generated from NASA/JPL’s RO back-up processor Rarely used BUFR products will be delivered from the primary processor unless an issue is encountered during operational processing that prevents product generation and/or distribution from the primary site. In such an event, products will be delivered from the back-up processor using the corresponding WMO routing header listed in the table above. The satellite code in the BUFR product for Sentinel-6 B is 67. Please let us know if you have any questions or encounter any issues with the new Sentinel-6 B data. Best, Chad, on behalf of the Sentinel-6 RO team [JPL logo] Chad Galley Technologist 362G | Near Earth Tracking Systems JPL 4800 Oak Grove Drive Pasadena, CA 91109 Mail Stop 238-600 M: 410.491.0024 O: 818.354.1013 F: 818.393.4965 chad.r.galley(a)jpl.nasa.gov<mailto:chad.r.galley@jpl.nasa.gov>

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Job announcement on GNSS Reflectometry at GFZ
by Jens Wickert 22 May '26

22 May '26

Dear colleagues, we are happy to announce an interesting job advertisement at GFZ. It is a key position for our activities in GNSS Reflectometry. https://www.gfz.de/en/career/job-offers/details/11262 We would be very grateful if you could spread it or even maybe take into consideration application. Thanks in advance and have a great day! Jens Wickert --------------------------------------- Prof. Dr. Jens Wickert GFZ Helmholtz Centre for Geosciences Section 1.1 Space Geodetic Techniques wickert(a)gfz.de <mailto:wickert@gfz.de> ----------------------------------------

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Invite you to submit your recent results to the Remote Sensing GNSS RO special issue
by Shu-peng Ho - NOAA Federal 07 May '26

07 May '26

Dear Colleagues, This is shu-peng Ben Ho from NOAA/STAR. You are cordially invited to submit your recent studies on GNSS RO to the Remote Sensing GNSS RO special issue ( https://www.mdpi.com/journal/remotesensing/special_issues/31G3890CC5#editors ). This Special Issue is designed to highlight a pivotal phase in the evolution of GNSS radio occultation. The field is moving beyond merely demonstrating broad usefulness—it is now increasingly defined by deeper scientific and technological questions, including bias diagnosis, uncertainty characterization, multi-mission consistency, lower-atmospheric retrieval challenges, operational value in numerical weather prediction, and emerging roles in ionospheric and space weather applications. With the rapid expansion of commercial constellations, international missions, and advanced processing approaches, GNSS RO is evolving from a mature observing technique into a more accurate, traceable, and integrable benchmark for remote sensing observations of Earth systems. This Special Issue aims to collect high-quality contributions that advance GNSS RO through methodological innovation, observational physics insights, rigorous inter-mission assessment, impactful applications, and the use of AI to improve the RO retrievals. This Special Issue will focus on recent advances in GNSS radio occultation in remote sensing, with particular emphasis on observational physics, bias and uncertainty diagnosis, multi-mission harmonization, advanced retrieval methods, and innovative applications in weather, climate, boundary-layer studies, high-impact events, ionospheric research, and space weather. We especially welcome contributions that address the following broader questions: How should GNSS RO observation errors and biases be characterized? How can consistency and long-term comparability be established across missions and processing systems? How can lower-tropospheric and boundary-layer retrieval be further improved? In what ways can GNSS RO serve as a benchmark for data assimilation and model evaluation? How might new signals, commercial constellations, AI-based methods, and future observing-system designs reshape the field? The Special Issue welcomes original research articles, review papers, and perspective articles covering, but not limited to, neutral atmospheric and ionospheric GNSS RO observations, retrievals, validation, data quality control, standardization, application assessment, and future system concepts. Topics include, but are not limited to, the following: - GNSS RO observation bias, uncertainty quantification, and error characterization; - Multi-mission consistency, harmonization, and climate data record development; - Geometry-related effects, tangent-point drift, antenna-viewing dependencies, and non-sphericity; - Advances in lower-tropospheric and boundary-layer GNSS RO retrieval; - GNSS RO data assimilation in global, regional, and convective-scale NWP; - GNSS RO as a benchmark observation for weather and climate model evaluation; - GNSS RO applications to tropical cyclones, heavy rainfall, severe weather, and other high-impact events; - Scientific and operational assessment of commercial GNSS RO constellations; - Ionospheric GNSS RO, TEC retrieval, and space weather applications; - AI, machine learning, and advanced inverse methods for GNSS RO; - Next-generation GNSS signals, receiver technologies, and future observing-system design; - Data quality control, metadata standards, reproducibility, and best practices in GNSS RO science; - The use of AI to improve the RO retrievals. Dr. Shu-peng Ho Dr. Michael E. Gorbunov *Guest Editors* *Manuscript Submission Information* Manuscripts should be submitted online at *www.mdpi.com* <https://www.mdpi.com/> by *registering* <https://www.mdpi.com/user/register/> and *logging in to this website* <https://www.mdpi.com/user/login/>. Once you are registered, *click here to go to the submission form* <https://susy.mdpi.com/user/manuscripts/upload/?journal=remotesensing>. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles, and short communications are invited. For planned papers, a title and short abstract (about 250 words) can be sent to the Editorial Office for assessment. Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-masked peer-review process. A guide for authors and other relevant information for manuscript submission are available on the *Instructions for Authors* <https://www.mdpi.com/journal/remotesensing/instructions> page. *Remote Sensing* <https://www.mdpi.com/journal/remotesensing/> is an international, peer-reviewed, open-access, semimonthly journal published by MDPI. Please visit the *Instructions for Authors* <https://www.mdpi.com/journal/remotesensing/instructions> page before submitting a manuscript. The *Article Processing Charge (APC)* <https://www.mdpi.com/about/apc/> for publication in this *open-access* <https://www.mdpi.com/about/openaccess/> journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's *English editing service* <https://www.mdpi.com/authors/english> before publication or during author revisions. *Keywords* - GNSS RO - boundary-layer retrievals - weather applications - atmospheric applications - benchmark observation for weather and climate model evaluation - AI applications on RO inversion *==============================================* *Shu-peng Ben Ho, Ph. D.* *GNSS Radio Occultation Physical** Scientist* *NOAA Center for Satellite Applications and Research (STAR)* *NCWCP, E/RA-21 Office# 2824* *5830 University Research Court, * *Riverdale Park, MD 20737* *Tel : (301) 683-3596* *Email: shu-peng.ho(a)noaa.gov <shu-peng.ho(a)noaa.gov>* *STAR GNSS RO Center: **https://gpsmet.umd.edu/gnssro/index.php <https://gpsmet.umd.edu/gnssro/index.php>* *STAR GNSS RO Data Service: **https://gpsmet.umd.edu/gnssro/download.php <https://gpsmet.umd.edu/gnssro/download.php>* *Publication: researchgate.net/profile/Shu-Peng-Ho/publications <http://researchgate.net/profile/Shu-Peng-Ho/publications>* *==============================================*

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Reminder: OPAC-IROWG 2026 Workshop, 10-16 Sept 2026, Austria, call for papers
by Ulrich Foelsche 05 May '26

05 May '26

================================================ Reminder: Call for Papers, April 29, 2026 We are pleased to announce: *OPAC-IROWG 2026* International Workshop on Occultations for Probing Atmosphere and Climate Joint OPAC-8 & IROWG-11 Workshop *September 10-16, 2026, Seggau Castle*, Leibnitz near Graz, Austria https://opacirowg2026.uni-graz.at/en/ Please be aware that the deadline - *May 3, 2026* - is quickly approaching https://opacirowg2026.uni-graz.at/en/abstract-submission/ There is very limited space for a deadline extension, since the *block reservation* at Seggau Castle is only secured until *May 31 *(promotion code: OPAC2026). U. Foelsche, J. Danzer, M. Schwärz, (WEGC & IPhys UniGraz, AT), OPAC Chairs H. Shao (JCSDA and UCAR, transitioning to Naval Research Lab., USA), IROWG Co-Chair A.J. Mannucci (JPL, Pasadena, USA), IROWG-CGMS Rapporteur ================================================== -- ************************************************************************** - Ulrich Foelsche - University of Graz - Institute of Physics, Department of Astrophysics and Geophysics (AGP) - Universitaetsplatz 5, 8010 Graz, Austria - Wegener Center for Climate and Global Change (WEGC) - Brandhofgasse 5, 8010 Graz, Austria - Tel: +43-316-380-8590 - E-mail: ulrich.foelsche(a)uni-graz.at **************************************************************************

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OPAC-IROWG 2026 Workshop, 10-16 Sept 2026, Austria, call for papers
by Foelsche, Ulrich (ulrich.foelsche＠uni-graz.at) 24 Apr '26

24 Apr '26

================================================ 2nd Announcement & Call for Papers, March 31, 2026 We are pleased to announce: OPAC-IROWG 2026 International Workshop on Occultations for Probing Atmosphere and Climate Joint OPAC-8 & IROWG-11 Workshop September 10-16, 2026, Seggau Castle, Leibnitz near Graz, Austria https://opacirowg2026.uni-graz.at/en/ **************************************************************************** An attractive forum for everybody interested in atmospheric remote sensing by occultation methods and/or the use of occultation data in atmospheric physics, meteorology, and climate. **************************************************************************** Please forward also to colleagues who might be interested. You are cordially invited to join OPAC-IROWG 2026 - Welcome! Please submit your abstract before May 3, 2026 via https://opacirowg2026.uni-graz.at/en/abstract-submission/ An earlier submission is, however, encouraged to ease your travel arrangements. We have reserved a block of rooms in Seggau Castle (promotion code: OPAC2026). This block reservation is secured until May 31. U. Foelsche, J. Danzer, M. Schwärz, (WEGC & IPhys UniGraz, AT), OPAC Chairs H. Shao (JCSDA and UCAR, USA), IROWG Co-Chair A.J. Mannucci (JPL, Pasadena, USA), IROWG-CGMS Rapporteur ==================================================

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Reminder: IROWG-11 and invitation letter request
by Hui Shao 24 Feb '26

24 Feb '26

Dear all, This is a brief reminder regarding the upcoming joint meeting. *IROWG-11* will be held together with the *OPAC-8 Workshop* from *September 10–16, 2026*, at *Seggau Castle*, Austria. The workshop website is still under construction available at https://opacirowg2026.uni-graz.at Once it is ready, abstract submission and registration will be announced through this email. In the meantime, participants who require *invitation letters for travel approval/visa applications* are encouraged to contact our IROWG co-chair and local host committee member, Dr. Uli Foelsche ( ulrich.foelsche(a)uni-graz.at) as early as possible, so we can help facilitate the process. We look forward to your participation and to welcoming you to Seggau Castle. Hui on behalf of IROWG-11

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