Projected 21st century decrease in marine productivity : a multi-model analysis
Frolicher, T. L.
Doney, Scott C.
Moore, J. Keith
MetadataShow full item record
Changes in marine net primary productivity (PP) and export of particulate organic carbon (EP) are projected over the 21st century with four global coupled carbon cycle-climate models. These include representations of marine ecosystems and the carbon cycle of different structure and complexity. All four models show a decrease in global mean PP and EP between 2 and 20% by 2100 relative to preindustrial conditions, for the SRES A2 emission scenario. Two different regimes for productivity changes are consistently identified in all models. The first chain of mechanisms is dominant in the low- and mid-latitude ocean and in the North Atlantic: reduced input of macro-nutrients into the euphotic zone related to enhanced stratification, reduced mixed layer depth, and slowed circulation causes a decrease in macro-nutrient concentrations and in PP and EP. The second regime is projected for parts of the Southern Ocean: an alleviation of light and/or temperature limitation leads to an increase in PP and EP as productivity is fueled by a sustained nutrient input. A region of disagreement among the models is the Arctic, where three models project an increase in PP while one model projects a decrease. Projected changes in seasonal and interannual variability are modest in most regions. Regional model skill metrics are proposed to generate multi-model mean fields that show an improved skill in representing observation-based estimates compared to a simple multi-model average. Model results are compared to recent productivity projections with three different algorithms, usually applied to infer net primary production from satellite observations.
© Authors, 2010. This work is distributed under the Creative Commons Attribution 3.0 License. The definitive version was published in Biogeosciences 7 (2010): 979-1005, doi: 10.5194/bg-7-979-2010
The following license files are associated with this item:
Showing items related by title, author, creator and subject.
Skill metrics for confronting global upper ocean ecosystem-biogeochemistry models against field and remote sensing data Doney, Scott C.; Lima, Ivan D.; Moore, J. Keith; Lindsay, Keith; Behrenfeld, Michael J.; Westberry, Toby K.; Mahowald, Natalie M.; Glover, David M.; Takahashi, Taro (2008-03-04)We present a generalized framework for assessing the skill of global upper ocean ecosystem-biogeochemical models against in-situ field data and satellite observations. We illustrate the approach utilizing a multi-decade ...
Atmospheric carbon dioxide variability in the Community Earth System Model : evaluation and transient dynamics during the twentieth and twenty-first centuries Keppel-Aleks, Gretchen; Randerson, James T.; Lindsay, Keith; Stephens, Britton B.; Moore, J. Keith; Doney, Scott C.; Thornton, Peter E.; Mahowald, Natalie M.; Hoffman, Forrest M.; Sweeney, Colm; Tans, Pieter P.; Wennberg, Paul O.; Wofsy, Steven C. (American Meteorological Society, 2013-07-01)Changes in atmospheric CO2 variability during the twenty-first century may provide insight about ecosystem responses to climate change and have implications for the design of carbon monitoring programs. This paper describes ...
Randerson, James T.; Lindsay, Keith; Munoz, E.; Fu, W.; Moore, J. Keith; Hoffman, Forrest M.; Mahowald, Natalie M.; Doney, Scott C. (John Wiley & Sons, 2015-06-02)Improved constraints on carbon cycle responses to climate change are needed to inform mitigation policy, yet our understanding of how these responses may evolve after 2100 remains highly uncertain. Using the Community Earth ...