CERISE project partners presented recent advances in coupled land–atmosphere data assimilation and global land reanalysis at the 8th WMO Symposium on Data Assimilation & 12th International Symposium for Data Assimilation, held at Nanjing University, Nanjing, China, from 31 August to 4 September 2026.
The international symposium brought together experts from across the data assimilation community to discuss the latest scientific and technical developments in the field. Representing CERISE, Christoph Herbert (ECMWF) and Luis Gustavo Gonçalves de Gonçalves (CMCC) shared project results in the “DA for Earth System” session. Further information about the event is available at da2026.cms1924.org/en/web/index/32441.
Advancing coupled land–atmosphere data assimilation
Christoph Herbert’s presentation, “Enhanced land–atmosphere coupled DA at ECMWF”, highlighted the final results of CERISE WP2 work on outer loop coupled land-atmosphere data assimilation and the exploitation of surface-sensitive observations through the eXtended Control Vector (XCV) for the global reanalysis prototypes of WP4. The presentation demonstrated how CERISE is contributing to improved approaches for representing land–atmosphere interactions in Earth system data assimilation.
Christophe Herbert presenting
Luis Gustavo Gonçalves de Gonçalves presented “CMCC-LDAS: A 21-Year Global Multivariate Ensemble Land Reanalysis (2002–2022)”, introducing the CERISE WP3 work performed by CMCC on land data assimilation system and its application to a long-term global multivariate ensemble land reanalysis for the CERISE WP5 seasonal prediction demonstrators. The work illustrates how extended land reanalysis datasets can support better understanding and monitoring of land surface conditions over time.
Luis Gustavo Gonçalves de Gonçalves presenting
Strengthening international exchange
Both presentations were well received by attendees and led to fruitful discussions, creating valuable opportunities to exchange ideas with the wider data assimilation community, including colleagues from numerous numerical weather prediction centres and universities. These discussions provided constructive feedback on the work completed within CERISE and helped shape possible next steps.
Reflecting on the event, Christoph Herbert said: “Presenting coupled land–atmosphere DA work at this event was extremely relevant to promote the project and to exchange information with the international DA community.”
Luis Gustavo Gonçalves de Gonçalves commented "ISDA gave us direct engagement with the international DA community on our framework approaches, and confirmed the relevance of CMCC-LDAS for operational seasonal prediction initialisation."
Patricia de Rosnay added: “ISDA is a high-level international data assimilation symposium. The strong topical relevance of this workshop for CERISE presented a unique opportunity to disseminate findings from CERISE to the community of experts, and to strengthen the CERISE project by getting feedback from members of the international scientific community working in this subject area. As such, presenting at ISDA was highly beneficial to the project, supporting next steps and international interactions.”
Article prepared by the project team with assistance from Copilot
