Sandia Labs FY22 Laboratory Directed Research & Development Annual Report

BIOMIMETIC CALCIFICATION FOR CARBON SEQUESTRATION FROM SEAWATER. An integrated data science and experimental

mechanisms that drive calcite formation, and, ultimately, decoupled the calcification process from photosynthetic carbon fixation. This will allow achievement of the project goal of increasing the per cell rate of calcification, thus removing more CO 2 from seawater. In the long term, by understanding the in vivo process, the team will be able to reconstitute the process in a hybrid bio/

approach is being taken to the challenges of direct capture of CO 2 from the ocean. A large group of marine microalgae, coccolithophores, produce calcium carbonate (calcite) plates referred to coccoliths. This calcification process

is linked to inorganic carbon acquisition for photosynthesis and plays an important role in the global carbon cycle. Researchers on this project discovered the genetic controls of the biological calcification processes, characterized the chemical

inorganic system able to carry out calcification without the biological limitations thus enhancing CO 2 capture. (PI: Todd Lane)

Numerous objectives are involved in helping researchers work on biomimetic calcification for carbon sequestration from seawater.

IMPROVING/TESTING ML METHODS FOR BENCHMARKING SOIL CARBON DYNAMICS REPRESENTATION OF LAND SURFACE MODELS.

Representation of soil organic carbon (SOC) dynamics in Earth system models (ESM) is a key source of uncertainty in predicting carbon climate feedbacks. The magnitude of this uncertainty can be reduced by accurate representation of environmental controllers of SOC stocks in ESMs. In this study, researchers used data of environmental factors, field SOC observations, ESM projections and ML approaches to identify dominant environmental controllers of SOC stocks and derive functional relationships between environmental factors and SOC stocks. Derived

mathematical relationships were derived to benchmark the coupled model intercomparison project phase six ESM representation of SOC stocks, and divergent environmental control representation in ESMs were found in comparison to field observations. Representation of SOC in ESMs can be improved by including additional environmental factors and representing their functional relationships with SOC consistent with observations. This project was highlighted in the Soil Science Society of America . (PI: Umakant Mishra)

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LABORATORY DIRECTED RESEARCH & DEVELOPMENT