Diagnosing the ocean’s sequestration efficiency using ACCESS-ESM1.5 transport matrices
Benoit Pasquier
Carbon dioxide removal (CDR) is required to limit global warming to 2°C, and many scientific institutions are investigating marine CDR (mCDR) strategies. Naturally, mCDR efficiency strongly depends on the sequestration efficiency of the ocean and is controlled by the time that water at depth takes to travel to the ocean surface. However, this transit can take hundreds if not thousands of years, as it occurs through many pathways characterized by long-tailed transit-time distributions (TTDs). While climate models can be used for simulating TTDs, multi-millennial simulations are typically prohibitively expensive. Here I will introduce an idealized but computationally efficient methodological framework based on transport matrices for computing TTDs from climate-model archives. We specifically applied this framework to simulate 3000 years of TTDs across the 40 members of the CMIP6 ACCESS-ESM1.5 archives for different ocean circulation climatologies. But this work should be of interest to anyone running long ocean tracer simulations, involved in mCDR research, or more broadly curious about efficient transport-matrix-based diagnostics of ocean transport in climate models.
Please use this thread for discussion about this talk.