23240 Rate this article: No rating Imaging Notes – Summer 2011 – Observing a Volatile Earth Imaging Notes – Summer 2011 – Observing a Volatile Earth Extreme weather is wreaking havoc in North America this year. The 2011 tornado season was record-setting, beginning in April with 438 confirmed twisters. The same extreme weather patterns causing tornadoes are also leading to heavy rainfall in the midwestern region of the continent. Please login or register to post comments. Science Computing World – Aug/Sept 2011 – Case In Point: Reading the Future Esri.com – September 2011 – Using Automatic 3D Building Extraction to Enhance Your GIS