Christopher C. Jenkins EAR-1118297 University of Colorado, Boulder PI: Potts, Donald C. EAR-1118306 University of California-Santa Cruz
Carbonate sediments are deposited extensively in the oceans and are a significant factor in global carbon budgets. But they are challenging to understand because they are created biologically, then modified geologically. Prior to this project, they had been modeled with rather simple rules-based methods which go under the name ?carbonate factory?. This project takes the next step and directly applies biological principles using advanced numerical modeling on the actual processes ? ?carbonate farm?. The population and community ecology of carbonate-skeleton organisms such as corals, bryozoans and algae is used to build realistic, detailed 3D time-geologic architectures. This opens productive new research paths into the carbon cycle, ocean acidification, rock properties, oil-gas resources, and environmental responses to global change. Perceptions that process modeling is not achievable are wrong ? the key is to employ good math tactics on the correct set of processes, for the key organisms, at appropriate time-space scales. In prototype this project has already produced emergent model features such as high-production ?bone yard? ecologies, and correct statistics for the variability of the accumulated sediments. The outputs can be compared even at the core-description level with Integrated Ocean Drilling Program (IODP) core logs and oil-industry reservoir variability statistics, promising cross-discipline results.
Most anthropogenic carbon dioxide being released into the atmosphere will eventually be removed and permanently sequestered as marine carbonate rocks (limestones) composed of the calcium carbonate skeletons of once-living organisms, including corals, coralline algae, molluscs, some other animals, some phytoplankton groups, and various micro-organisms. Permanent sequestration requires that rates of carbonate deposition must exceed rates of carbonate destruction by physical, chemical and biological erosion. This project created a pilot digital KnowledgeBase (carboKB) designed to support development of a suite of models (carbo*) describing the formation, persistence and fates of marine carbonate structures (e.g. coral reefs, algal beds (maerl and Halimeda), oyster reefs). The interdisciplinary carbo* models are integrating biological and geological processes across many spatio-temporal scales – from the ecology of individual organisms to the final geological structures. Initial models are exploring current processes on coral reefs. After validating and calibrating the models by simulating past processes to create extant reefs, the major goal will be to explore the future effects of climate change, rising sea levels, increasing temperatures, and especially ocean acidification on coral reefs and other carbonate systems. The pilot carboKB was created by searching for published and online quantitative ecological and environmental data on factors affecting calcification or bio-erosion by representative, widely-distributed species. Biological entries include recruitment, growth, survival, longevity, morphology, and responses to extreme conditions; environmental data include aspects of locality, habitat, depth, temperature, water chemistry, and physical and biological disturbances. After final editing for consistency and compatibility with carbo* models, the pilot carboKB will be made available as an online lookup resource on the website of the Community Surface Dynamics Modeling System (CSDMS) at the University of Colorado, Boulder. Marine carbonates are a critical component of the extremely complex atmospheric-oceanic carbon dioxide cycle and an interdisciplinary understanding of their production is essential for predicting and perhaps mitigating the consequences of climatic and oceanic changes driven by anthropogenic carbon dioxide emissions. carboKB is intended to assist this understanding by providing a flexible, dynamic and continually updatable open-access resource that is responsive to the needs of carbonate scientists worldwide. Once appropriate quality control protocols are established, we plan to add a capability for users to enter additional species and/or data types.