The 2023 IUGG General Assembly took place at CityCube Berlin in Germany 11-20 July 2023, with all cryosphere sessions scheduled 12-16 July. All participants were required to follow the IUGG Code of Conduct.

The scientific program included 15 IACS sessions on glaciers, ice sheets, sea ice, snow and permafrost, and more than 15 cryosphere-related symposia joint with other IUGG associations. The IACS keynote Union Lecture was given by Ricarda Winkelmann (Potsdam Institute for Climate Impact Research). IACS held an open plenary meeting for its members and correspondents, and new officers were elected for the IACS Bureau for the 4-year term 2023-2027.

Former president Charles Fierz was awarded Honorary Membership. Several IACS working groups, standings groups, joint commissions and bodies held splinter meetings during IUGG. See list of meetings below.

IACS highlights also included:
• Graham Cogley awards for student oral and poster presentations (audience nominations sought)
• IUGG Early Career Award talks and IUGG Gold medal lecture, see list below.
• Festa Cryospherica social gathering and dinner at Restaurant Neumanns (Alt – Moabit 126, 10557 Berlin) after the plenary meeting on Saturday 15 July. Open to all participants interested in the cryosphere. Purchase tickets for €80 per person (buffet with meat, vegetarian and vegan choices, drinks included). IACS Business meetings • Closed bureau meeting, room R5, Tuesday 11 July, 09:00-13:00 (for IACS bureau 2019-2023) • Open plenary meeting, room New York 2, Saturday 15 July, 17:00-19:00 (followed by Festa Cryospherica dinner) • Closed bureau meeting, room R12, Monday 17 July, 09:00-13:00 (for IACS bureau 2023-2027) Side meetings • GlacierMIP (Regine Hock), room R4, Tuesday 11 July, 14:00-18:00 • GlacierMIP (Regine Hock), room R2, Wednesday 12 July, 12:30-13:30 • ISMIP6, room M2, Wednesday 12 July, 09:00-17:00 • RGI/Ice boundaries (Fabien Maussion), room R2, Thursday 13 July, 12:30-13:30 • GTN-G (Michael Zemp), room R12, Friday 14 July, 12:30-13:30 • OCEAN:ICE interactions - Ice sheet impacts on ocean circulation and climate feedbacks, room R2, Friday 14 July, 08:30-10:00 • JB-SMSC (Wolfgang Schoener), room R12, Saturday 15 July, 12:30-13:30 • Sunday 16 July, 12:30-13:30 IACS related IUGG award talks and union lecture • IUGG Early Career Scientist Award talks (Farooq Azam, Natalya Gomez, Johan Gaume), Wednesday 12 July, 15:30-17:00 • IACS keynote Union Lecture by Ricarda Winkelmann, Friday 14 July, 10:30-11:30 • IUGG Gold medal lecture by Valerie Masson-Delmotte, Saturday 14 July, 13:30-15:00 IACS symposia at IUGG Berlin 2023 • C01 Advances in Modelling Glaciers and Ice Caps – Past Reconstructions, Future Projections, and Process-Based Studies Orals: Thursday 13 July 08:30-10:00, 10:30-12:00 Posters: Wednesday 12* and Thursday 13 July • C02 Glacier Changes in High Mountain Asia and the Karakoram Anomaly: Latest Insights from the Atmosphere and Cryosphere Orals: Thursday 13 July 13:30-15:00 Posters: Wednesday 12* and Thursday 13 July • C03 Debris Covered Glaciers Orals: Sunday 16 July 08:30-10:00 Posters: Saturday 15 and Sunday 16* July • C04 Fast Glacier Flow: Processes, Observations and Modelling of Ice Streams, Tidewater Glaciers and Surging Glaciers Orals: Sunday 16 July 13:30-15:00 Posters: Saturday 15 and Sunday 16* July • C05 Tropical Glaciers: Mass Changes, Climate Forcing and Impacts on Indigenous Communities Orals: Friday 14 July 08:30-10:00 Posters: Saturday 15* and Sunday 16 July • C06 New Frontiers in Paleoclimate Reconstructions and Proxy Interpretations from Ice Cores Orals: Wednesday 12 July 08:30-10:00, 10:30-12:00 Posters: Wednesday 12* and Thursday 13 July • C07 Mass Changes of The Cryosphere – The Need for and Lessons Learned from Intercomparison Exercises Orals: Sunday 16 July 13:30-15:00, 15:30-17:00 Posters: Saturday 15 and Sunday 16* July • C08 Challenges in Modeling, Monitoring and Predicting Alpine Mass Movements Orals: Wednesday 12 July 13:30-15:00 Posters: Wednesday 12* and Thursday 13 July • C09 Mountain Snow Cover Under Climate Change: From Past to Future Orals: Saturday 15 July 15:30-17:00 Posters: Saturday 15* and Sunday 16 July • C10 Satellite-Derived Snow Cover Products and Their Applications in Hydrology Orals: Friday 14 July 08:30-10:00 Posters: Wednesday 12* and Thursday 13 July • C11 Light Absorbing Particles on Snow and Ice Posters: Wednesday 12* and Thursday 13 July • C13 Data driven Cryospheric Sciences: Machine Learning, Data Assimilation and Inverse Methods for the Cryosphere Orals: Friday 14 July 08:30-10:00 Posters: Friday 14* and Saturday 15 July • C14 Cryospheric Processes and Related Socioeconomic Impacts Orals: Sunday 16 July 15:30-17:00 Posters: Saturday 15 and Sunday 16* July * Poster presententers in attendance IACS joint symposia at IUGG Berlin 2023 • JC01 Remote Sensing of the Cryosphere (IACS, IAHS) Orals: Wednesday 12 July 08:30-10:00, 10:30-12:00, 13:30-15:00; Thursday 13 July 08:30-10:00, 10:30-12:00 Posters: Wednesday 12* and Thursday 13 July • JC02 Declining Glacier, Snow Cover and Permafrost and Their Impacts on Downstream Hydrology (IACS, IAHS, IAG) Orals: Thursday 13 July 13:30-15:00, 15:30-17:00 Posters: Thursday 13 and Friday 14* July • JC03 Coupling Processes Between the Atmospheric Boundary-Layer and Snow - Ice Surfaces: Modelling at Convection and Snowdrift-Permitting Scales (IACS, IAHS, IAMAS) Orals: Saturday 15 July 15:30-17:00 Posters: Saturday 15* and Sunday 16 July • JC04/C15 Atmospheric Circulations and Surface Mass Balance of Ice Sheets (IACS, IAMAS) Orals: Saturday 15 July 15:30-17:00 Posters: Saturday 15* and Sunday 16 July • JC05/M16 Atmosphere-Ocean-Sea Ice Interactions: Physical and Chemical Processes (IACS, IAMAS, IAPSO) Orals: Friday 14 July 13:30-15:00, 15:30-17:00; Saturday 15 July 08:30-10:00, 10:30-12:00, 13:30-15:00 Posters: Friday 14* and Saturday 15 July • JC06 Mountain Cryosphere Hazards (IACS, IAVCEI, IASPEI) Orals: Saturday 15 July 08:30-10:00, 10:30-12:00 Posters: Saturday 15* and Sunday 16 July Joint symposia involving IACS at IUGG Berlin 2023 • JA02 Data Assimilation and Statistical Learning in Earth and Space Sciences Orals: Friday 14 July 08:30-10:00, 13:30-15:00, 15:30-17:00 Posters: Friday 14* and Saturday 15 July • JA03 Analogue Data for the Future: Preservation and Present-Day Utilization of Historical Data in the Geosciences Orals: Saturday 15 July 08:30-10:00, 10:30-12:00, 13:30-15:00 Posters: Saturday 15* and Sunday 16 July • JG01 Interactions of the Solid Earth with Ice Sheets and Sea Level Orals: Friday 14 July 08:30-10:00, 13:30-15:00, 15:30-17:00 Posters: Friday 14* and Saturday 15 July • JG05 Geodesy for Climate Research Orals: Wednesday 12 July 08:30-10:00, 10:30-12:00, 13:30-15:00, 15:30-17:00; Thursday 13 July 08:30-10:00, 10:30-12:00 Posters: Wednesday 12* and Thursday 13 July • JH01 New, Large, and Open Data for the Earth and Environmental Science Community Orals: Sunday 16 July 08:30-10:00, 13:30-15:00 Posters: Saturday 15 and Sunday 16* July • JH02 Advances in Snow Hydrology Orals: Wednesday 12 July 08:30-10:00, 10:30-12:00, 13:30-15:00 Posters: Wednesday 12* and Thursday 13 July • JH03 Snow in the Critical Zone Orals: Wednesday 12 July 15:30-17:00 Posters: Wednesday 12* and Thursday 13 July • JH05 Citizen Science, Crowdsourcing and Innovative Monitoring for Advancing Geo-Sciences Orals: Sunday 16 July 15:30-17:00 Posters: Saturday 15 and Sunday 16* July • JH06 Education & Outreach in Geosciences Orals: Saturday 15 July 08:30-10:00, 10:30-12:00, 13:30-15:00 Posters: Saturday 15 and Sunday 16* July • JM01 Recent Advances in Regional Climate Modelling Orals: Friday 14 July 13:30-15:00, 15:30-17:00 Posters: Friday 14* and Saturday 15 July • JM02 Tropical-Polar Interactions, Arctic Amplification and Its Influence on Midlatitude Weather Orals: Saturday 15 July 08:30-10:00, 10:30-12:00, 13:30-15:00 Posters: Saturday 15* and Sunday 16 July • JM03 Polar Regions Instrumentation Orals: Saturday 15 July 15:30-17:00 Posters: Saturday 15* and Sunday 16 July • JM05 Earth System Models Orals: Sunday 16 July 13:30-15:00, 15:30-17:00 Posters: Saturday 15* and Sunday 16 July • JP02 Arctic Ocean Physics and Biochemistry in a Changing Climate Orals: Sunday 17 July 08:30-10:00, 10:30-12:00, 15:30-17:00 Posters: Saturday 15 and Sunday 16* July • JP03 Physical and Biogeochemical Ocean and Ice Processes in the Southern Ocean: Observations, State Estimation and Modeling Orals: Wednesday 12 July 08:30-10:00, 10:30-12:00, 13:30-15:00, 15:30-17:00; Thursday 13 July 08:30-10:00 Posters: Wednesday 12* and Thursday 13 July • JP04 Ice Sheet-Ocean Interactions: Challenges and Insights from Theory, Observations and Modelling Orals: Friday 14 July 15:30-17:00; Saturday 15 July 08:30-10:00, 10:30-12:00, 13:30-15:00 Posters: Friday 14* and Saturday 15 July • JP06 Electromagnetic Studies of the Ice and Ocean System Orals: Thursday 13 July 13:30-15:00 Posters: Thursday 13 and Friday 14* July • JS01 Cryoseismology Orals: Sunday 16 July 08:30-10:00, 13:30-15:00 Posters: Saturday 15 and Sunday 16* July