As a result, the distribution,[11] productivity, and species composition of global fish production is changing,[12] generating complex and inter-related impacts[3] on oceans, estuaries, coral reefs, mangroves and sea grass beds that provide habitats and nursery areas for fish. Changing rainfall patterns and water scarcity is impacting on river and lake fisheries and aquaculture production.[4][5] After the ice age about 200,000 years ago, the global air temperature has risen 3 degrees, leading to an increase in sea temperatures.[16]