North-South asymmetry in the modeled phytoplankton community response to climate change over the 21st century
Supplementary Table 1. Present area of the modeled ecological biomes (calculated for years 1980-1999) and the response of the biome areas to global warming in the 21st century. (58.11Kb)
Doney, Scott C.
Lima, Ivan D.
Moore, J. Keith
Mahowald, Natalie M.
MetadataShow full item record
Here we analyze the impact of projected climate change on plankton ecology in all major ocean biomes over the 21st century, using a multidecade (1880–2090) experiment conducted with the Community Climate System Model (CCSM-3.1) coupled ocean-atmosphere-land-sea ice model. The climate response differs fundamentally in the Northern and Southern Hemispheres for diatom and small phytoplankton biomass and consequently for total biomass, primary, and export production. Increasing vertical stratification in the Northern Hemisphere oceans decreases the nutrient supply to the ocean surface. Resulting decreases in diatom and small phytoplankton biomass together with a relative shift from diatoms to small phytoplankton in the Northern Hemisphere result in decreases in the total primary and export production and export ratio, and a shift to a more oligotrophic, more efficiently recycled, lower biomass euphotic layer. By contrast, temperature and stratification increases are smaller in the Southern compared to the Northern Hemisphere. Additionally, a southward shift and increase in strength of the Southern Ocean westerlies act against increasing temperature and freshwater fluxes to destratify the water-column. The wind-driven, poleward shift in the Southern Ocean subpolar-subtropical boundary results in a poleward shift and increase in the frontal diatom bloom. This boundary shift, localized increases in iron supply, and the direct impact of warming temperatures on phytoplankton growth result in diatom increases in the Southern Hemisphere. An increase in diatoms and decrease in small phytoplankton partly compensate such that while total production and the efficiency of organic matter export to the deep ocean increase, total Southern Hemisphere biomass does not change substantially. The impact of ecological shifts on the global carbon cycle is complex and varies across ecological biomes, with Northern and Southern Hemisphere effects on the biological production and export partially compensating. The net result of climate change is a small Northern Hemisphere-driven decrease in total primary production and efficiency of organic matter export to the deep ocean.
Author Posting. © American Geophysical Union, 2013. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Global Biogeochemical Cycles 27 (2013): 1274–1290, doi:10.1002/2013GB004599.
Showing items related by title, author, creator and subject.
Marine ecosystem dynamics and biogeochemical cycling in the Community Earth System Model [CESM1(BGC)] : comparison of the 1990s with the 2090s under the RCP4.5 and RCP8.5 scenarios Moore, J. Keith; Lindsay, Keith; Doney, Scott C.; Long, Matthew C.; Misumi, Kazuhiro (American Meteorological Society, 2013-12-01)The authors compare Community Earth System Model results to marine observations for the 1990s and examine climate change impacts on biogeochemistry at the end of the twenty-first century under two future scenarios ...
Moore, J. Keith; Doney, Scott C.; Lindsay, Keith (American Geophysical Union, 2004-12-14)A global three-dimensional marine ecosystem model with several key phytoplankton functional groups, multiple limiting nutrients, explicit iron cycling, and a mineral ballast/organic matter parameterization is run within a ...
Preindustrial-control and twentieth-century carbon cycle experiments with the Earth System Model CESM1(BGC) Lindsay, Keith; Bonan, Gordon B.; Doney, Scott C.; Hoffman, Forrest M.; Lawrence, David M.; Long, Matthew C.; Mahowald, Natalie M.; Moore, J. Keith; Randerson, James T.; Thornton, Peter E. (American Meteorological Society, 2014-12-15)Version 1 of the Community Earth System Model, in the configuration where its full carbon cycle is enabled, is introduced and documented. In this configuration, the terrestrial biogeochemical model, which includes ...