During the past 100 years or so, the ocean surface has become more acidic by 0.1 pH units [Orr et al., 2005] and has warmed by 0.6°C [Folland et al., 2001]. In recent decades, temperature and salinity changes [Curry et al., 2003] suggest modifications in ocean circulation and thus in the distribution of surface nutrients. Surface nutrients also are being modified by changes in fluvial supply and by changes in aeolian transport of nutrient-enriched dust. In addition, over-fishing modifies the predation on large zooplankton by small fish and could have topdown effects on the lower food web. These changes affect marine ecosystems in ways that are neither well understood nor quantified.
If you can't find a tool you're looking for, please click the link at the top of the page to "Go to old article view". Alternatively, view our Knowledge Base articles for additional help. Your feedback is important to us, so please let us know if you have comments or ideas for improvement.