This Why Files feature posted November 6, 1997 explains some of the tools employed by the climatologist, and how they are used to measure climate or look back in time to see what climate was like long ago. How do scientists forecast what might be in store for the planet? Topics include how scientists take the Earth's temperature and use computer-based climate models, ice cores from remote glaciers and ice caps, lake sediments, archaeology, and tree rings to help them look back in time. Five scientists were interviewed for this report. Educational levels: General public, High school, Intermediate elementary, Middle school
