Data Assimilation (DA-TT)
The DA-TT brings together experts in the field from leading operational centres, research institutions, and groups from academia in a shared dialog about the current state-of-the-art, and common challenges faced by the ocean Data Assimilation (DA) community. The primary vehicles are regular workshops and collaborative activities. Since DA is an essential and common thread to many of the OceanPredict goals, an additional role of DA-TT is to catalyse interactions with other TTs.
The DA-TT promotes capacity building in several areas, including: the development of modelling, assimilation, and forecasting approaches and components; demonstrations of accuracy and utility; research value; and intellectual capacity building. The DA-TT also provides a conduit to the broader WMO data assimilation and prediction community. The ocean DA community is small compared to its atmospheric counterpart, and as such, capacity building to meet the current and future demands of the field is an important TT goal. Future DA-TT activities will therefore continue to expand capacity building activities, particularly in relation to intellectual capital, with a view to sustaining an active and vibrant ocean DA community.
The DA-TT will foster coordination and monitor progress in activities related to:
- Development of data assimilation algorithms.
- Development of coupled data assimilation methods in collaboration with the CP-TT.
- Assimilation of novel observations (under-utilised existing networks and upcoming missions) in collaboration with the OSEVal-TT and with the MEAP-TT.
- Assimilation software infrastructure developments and application to new HPC architectures, as related to the adoption of tools developed in the wider data assimilation community which allow enhanced collaborations among operational agencies, research institutes and universities.
- Performance assessment of data assimilation applications in the operational community, in collaboration with the IV-TT.
- Application of data-driven algorithms (machine learning and deep learning) for improved pre-processing and exploitation of consolidated and new observing networks.
A major activity of the DA-TT is to organise regular meetings and workshops. In order to increase collaboration, these workshops are often held jointly with other TTs or groups.
The DA-TT coordinates inter-comparison activities aimed at improving our understanding of the operational data assimilation systems used by OceanPredict groups. These have previously included comparison of average increments to understand biases in the ocean models and forcing, and comparison of the impact of observations using idealised, widely spaced observations.
The DA-TT also coordinates contributions to other international activities. We have previously contributed to international conferences such as OceanObs’19 (Moore et al., 2019) and to the 2016 international workshop on coupled data assimilation (Penny et al., 2017).
Moore AM, Martin MJ, Akella S, Arango HG, Balmaseda M, Bertino L, Ciavatta S, Cornuelle B, Cummings J, Frolov S, Lermusiaux P, Oddo P, Oke PR, Storto A, Teruzzi A, Vidard A and Weaver AT (2019). Synthesis of Ocean Observations Using Data Assimilation for Operational, Real-Time and Reanalysis Systems: A More Complete Picture of the State of the Ocean. Front. Mar. Sci. 6:90. doi: 10.3389/fmars.2019.00090.
Penny, S.G., S. Akella, O. Alves, C. Bishop, M. Buehner, M. Chevallier, F. Counillon, C. Draper, S. Frolov, Y. Fujii, A. Karspeck, A. Kumar, P. Laloyaux, J.-F. Mahfouf, M. Martin, M. Peña, P. de Rosnay, A. Subramanian, R. Tardif, Y. Wang, X. Wu. 2017. Coupled Data Assimilation for Integrated Earth System Analysis and Prediction: Goals, Challenges and Recommendations. WWRP 2017-3
Members of the DA-TT
|No||First name||Last name||Institutions/projects||Country||Status|
|10||Pierre||De Mey-Fremaux||LEGOS||France||Member and co-chair of the COSS-TT|
|12||Patrick||Heimbach||University of Texas at Austin||USA||Member|
|13||Young Ho||Kim||KIOST||South Korea||Member|
|14||Alexander||Kurapov||Oregon State University / NOAA||USA||Member|
|TBC||Peter||OKE (TBC)||CSIRO||Australia||Member ?|
|23||Jozef||Skakala||PML||UK||New member (14 Sep 20)|
|24||Gregory||Smith||Environment Canada||Canada||Member and co-chair of the IV-TT|
|28||Clemente||Tanajura||UFBA / REMO||Brazil||Member|
Johnny Johannessen, NERSC
Status: September 2020
Meetings and workshops
A major activity of the DA-TT is to organise regular workshops. In order to increase collaboration, these workshops are often held jointly with other TTs or groups. Planned and previous workshops include:
The DA-TT is involved in the ESA A-TSCV project, to work of the assimilation of Total Surface Current Velocity Measurements.
Find out more from the A-TSCV project page.
The task team quad-chart provides a quick glance at the TT’s activities, achievements and future plans.
Data Assimilation Task Team (DA-TT) – October 2019
|Short description and objectives of the activities started or planned for this year:
||Accomplishments of the TT this year:
1. Improving understanding of error covariances used in existing DA systems through coordinated “multiple widely-spaced observation” experiments.
2. Identifying and quantifying model and forcing bias through inter-comparison of average assimilation increments.
3. Promote the development of hybrid data assimilation methods in the ocean
4. Organise meetings aimed at fostering the development of the DA systems
• The DA-TT co-chairs were active in the organization of the OceanPredict ’19 symposium in Halifax, NS.
• As part of OceanPredict ’19 a very successful DA training session was organized, with over 70 participants.
• The DA-TT co-chairs co-authored, with TT members, a mini-review paper published in Frontiers in Marine Science in support of OceanObs19.
• Several DA-TT members were active participants at OceanObs19, leading a discussion forum on ocean DA.
• Several new members have been invited to join the task team to expand representation from other international communities.
|Future plans to continue/ improve current activities:
|Main future plans:
• Work plan item 1 has been on-hold because of preparation for the OceanPredict19 symposium and OceanObs19 white paper. This activity will resume pending TT engagement.
• Work plan item 2 has also been on hold, although several other groups have expressed interest in contributing.
• Organization of a TT workshop is under way for Jan 2020 at CERFACS, Toulouse.
• The DA-TT co-chairs are working with MEAP-TT to organize a dedicated DA session at their next workshop in 2020.
• Co-chair Moore will engage with wider DA community via his role as a member of the WMO WWRP DAOS WG.
• Need to move the work plan items forward with very little time/resource dedicated to the assessment work.
• Need to encourage more groups to contribute to the inter-comparisons.
• More engagement by the DA-TT patron
Resources needed to better support the TT effort:
• Dedicated funding for a scientist to analyse the results of the inter-comparison experiments would greatly improve their impact.