Oceans and the Changing Climate

Abstract

Increasing levels of atmospheric greenhouse gases are producing changes in the world’s oceans and coastal environments, such as increasing sea surface temperatures, ocean acidification, and rising sea levels. This chapter explores the human dimensions of three climate change impacts: (1) rising sea levels, measures to adapt, and the potential displacement of persons from eroding, low-lying coastal areas; (2) the migration of fish stocks to new habitats resulting from increasing seawater temperatures; and (3) the degradation of coral reefs and impacts to shellfish resulting from ocean acidification. With sea level rise, millions of people in low-lying coastal cities and small island developing states must adapt or be displaced, and some will become climate refugees. In the case of fisheries, distributions of some fish stocks are already changing because of increasing ocean temperatures. These shifts have great implications for both fishers and managers of marine resources. Finally, rising atmospheric concentrations of CO2 that lower the ocean’s pH make it more difficult for corals and shellfish to precipitate the calcium carbonate that forms their exoskeletons and shells, affecting users of tropical coral reef ecosystems as well as the shellfish aquaculture industry.