Abundance of Southern macro-invertebrate species and declines in northern species in a rocky intertidal community on California coast are consistent with recent climate warming (Sargarin et al., 1999). Warming annual temperature is suggested as a probable cause of abundance of plankton in German Bight but factors including regional eutrophication also have been noted (Grove et al., 1996).
Distribution of phytoplankton biomass in northern San Francisco Bay Estuary was influenced by environmental conditions resulting from an interdecadal climate regime shift between 1975 and 1993. Precipitations regimes primarily implicated with water temperature also play an important role (Lehman, 2000). Ross et al., (1994) attributed the loss of low elevation pine forests in Florida because of rising sea level.
Observed impacts of regional climate changes from socioeconomic systems is much sparser than from physical and biological systems. Methodologically, it is difficult to separate climate effects from factors like technological change and economic development, given the complexities of these systems. Vulnerability to climate change and variability is a function of exposure and adaptive capacity.
Exposure varies from region to region, sector to sector, community to community. Adaptive capacity may be even more variable. Adaptive capacity of socioeconomic systems also contributes to difficulty of documenting effects of regional climate changes. Observable effects may be adaptations to a climate changes rather than direct impacts.
Adaptation of many of this system to multiple stresses, including climate variability suggests that complexities inherent in socioeconomic systems could be a source of resilience with potential for beneficial adaptations in some cases.