<http://schema.org/about>
"Due to climate change's effects on weather systems, powerful storms like Hurricane Irene, once considered rare, could occur every 3 to 20 years."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/climate-change/100-year-storms-may-start-arriving-every-three-years.html>