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In marine ecosystems, rising atmospheric CO2and climate change are associated with concurrent shifts in temperature, circulation, stratification, nutrient input, oxygen content, and ocean acidification, with potentially wide-ranging biological effects. Population-level shifts are occurring because of physiological intolerance to new environments, altered dispersal patterns, and changes in species interactions. Together with local climate-driven invasion and extinction, these processes result in altered community structure and diversity, including possible emergence of novel ecosystems. Impacts are particularly striking for the poles and the tropics, because of the sensitivity of polar ecosystems to sea-ice retreat and poleward species migrations as well as the sensitivity of coral-algal symbiosis to minor increases in temperature. Midlatitude upwelling systems, like the California Current, exhibit strong linkages between climate and species distributions, phenology, and demography. Aggregated effects may modify energy and material flows as well as biogeochemical cycles, eventually impacting the overall ecosystem functioning and services upon which people and societies depend.

The article presents a study which shows the effect of climate change on the production and distribution of commercial fisheries off Alaska. The study employs the real-time oceanographic data acquisition, management strategy evaluation (MSE), and climate indices. Result shows that the distribution and abundance of groundfish stocks will be influenced by climate change. It adds that simulation models have been used to inform fisheries management decisions in Bering sea and Gulf of Alaska.

The article discusses a framework for quantifying climate-induced shifts in pelagic ocean habitats and incorporating the shifts into the walleye pollock stock assessment to determine variables governing growth and recruitment.

The article discusses the highlights of the February 2012 meeting of the North Pacific Fishery Management Council which focused on stock-recruitment (SR) issues. Presentations are presented to have used statistical methods to address regime shifts in stock production. Researchers Jim Ianelli and Tom Wilderbuer talked about incorporating variables representing environmental forcing into the SR relationship. A statistical method to estimate mean recruitment and sigma R was introduced.