Marine Biogeochemistry in CMIP5 Models
Abstract
We determine the ability of 10 Earth system models to simulate biogeochemical observations of present conditions, and assess simulated changes since preindustrial conditions, with a focus on ocean surface chlorophyll and marine primary production. Model performance is assessed over the reference period 1986-2005. Metrics are computed for averaged seasonal cycles of biogeochemical variables. These metrics are evaluated for the current generation (CMIP5) and older generation (OCMIP5) models to assess recent model improvements. Seasonal patterns in the models are analysed by comparing the month and magnitude of the maximum chlorophyll bloom with SeaWiFS estimates at the grid scale. The models are generally consistent with observations but are frequently out of phase by up to 6 months in the Southern Ocean. The co-variability of chlorophyll and SST is evaluated over several decades. Modeled chlorophyll-a anomalies and changes in Nino region 3.4 SST show a strong negative correlation in the equatorial pacific in many of the models. No significant long-term trend in chlorophyll, primary production or export production since preindustrial times is evident in any of the models.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2012
- Bibcode:
- 2012AGUFMOS31B1725K
- Keywords:
-
- 4800 OCEANOGRAPHY: BIOLOGICAL AND CHEMICAL;
- 4805 OCEANOGRAPHY: BIOLOGICAL AND CHEMICAL / Biogeochemical cycles;
- processes;
- and modeling;
- 4815 OCEANOGRAPHY: BIOLOGICAL AND CHEMICAL / Ecosystems;
- structure;
- dynamics;
- and modeling;
- 4855 OCEANOGRAPHY: BIOLOGICAL AND CHEMICAL / Phytoplankton