GEF

Unit 2  |  Water Science and the Water Cycle 47 South American rain forests (left) receive high amounts of precipita- tion while North Africa (right) receives little. Climate change is also worsening the unequal distribution of water, as wetter areas receive heavier precipitation and arid regions become drier. Water availability patterns present a major challenge to developing sustainable and equitable access to this essential resource. CLIMATE CHANGE A long-term alteration in the Earth’s weather patterns and temperature, caused primar- ily by human emissions of greenhouse gases. ?  DID YOU KNOW 71 percent of the Earth’s sur- face is water. WATCH & LEARN http://bit.ly/2gLp4fM Watch the video and respond to the questions below. 1. How much of the Earth’s water is available for human use? 2. What are the two largest sources of freshwater? 3. What are some reasons that not all freshwater is accessible for human use? video: Fresh Water is a Limited Resource