This document discusses global warming and its impacts. It defines global warming as an increase in average temperatures caused by too much carbon dioxide trapping heat in the atmosphere. This can lead to rising sea levels from melting ice caps, endangering coastal cities and polar animals' habitats. The document recommends individual actions like biking and using less electricity to help address the problem. It also notes global warming harms marine life by acidifying oceans as carbon dioxide dissolves into carbonic acid.