For example, our forests remove carbon dioxide and other pollutants from the air we breathe and also cool our air temperatures, reducing the formation of ground-level ozone, a pollutant that can cause heart and lung problems to worsen; our wetlands store storm water, filter and make harmless storm water pollutants, and recharge our aquifers (where most of us get our drinking water) with these filtered waters; and the dune systems on our beaches form natural barriers to storm waves and provide important habitat and travel ways for wildlife.