Slide image: Three graphs showing "Global average temperature" (top), "Global average sea level" (center), and "Northern Hemisphere snow cover" (bottom) from the year 1850 to around 2006. The first two are rising. The snow cover is generally decreasing.

Slide image credit: © IPCC 2007 WG1-AR4
IPCC FOURTH ASSESSMENT REPORT, CLIMATE CHANGE 2007 (AR4), Figure SPM.3

Background image: Photo showing thunderstorm over a city

Background image credit: © University Corporation for Atmospheric Research

Design by: Adrian Apodaca, National Science Foundation