One of the most pronounced impacts of climate change is intensification in the water cycle: warmer air speeds up evaporation and also holds more moisture, so the dry areas get drier, and the storms get bigger and more intense. The root causes of the disasters of 2011 were mainly either not enough water or too much falling at once (or tornadoes associated with excessively powerful thunderstorms).

Climate change seems poised to continue to deliver more and deadlier punches in the future. And even if a serious effort to reduce global warming pollution gets underway soon, the carbon dioxide already in the atmosphere will stay there for centuries. With more years like 2011 undoubtedly to come, we must begin preparing for, and attempting to lessen, the risks associated with extreme weather.

Building bigger levees, higher dams and stronger seawalls might protect some areas from larger rains and floods, but could also put other communities at risk. Higher levees, for instance, funnel more water downstream, resulting in greater flooding there, as well as catastrophic consequences for local communities should a levee fail. Moreover, in an era of declining budgets at all levels of government, massive investments in “hard infrastructure” may not be forthcoming even in the face of serious climate threats. By preserving and rebuilding our green infrastructure—floodplains, wetlands, forests and other natural components of our ecosystems that work together as a whole to provide “ecosystem services” such as flood control and water filtration—we can “harness nature” to help provide protection from extreme events.

The purpose of this report is to promote this strategy of harnessing nature as an essential, viable and cost-effective approach to climate-change preparedness. To underscore the urgency of the need to act now, the report begins with a review of the extreme weather events of 2011 and a sobering summary of the latest weather trends and scientific predictions about climate events. It summarizes the promise and benefits of strengthening and enhancing our green infrastructure and offers inspiring case studies of communities around the country that are already harnessing nature to lessen the impacts of floods, storms, droughts, wildfires and rising sea levels. The report concludes with recommendations to help agencies and communities incorporate ecosystem-based measures into their climate-change adaptation plans, i.e., to harness the power of nature.