The Florida Everglades is a swampy wilderness the size of Delaware. In some places along the road in southern Florida, it looks like tall saw grass to the horizon, a prairie punctuated with a few twisted cypress trees. The sky is the palest blue.But beneath the surface a different story is unfolding. Because of climate change and sea level rise, the ocean is starting to seep into the swampland. If the invasion grows worse, it could drastically change the Everglades, and a way of life for millions of residents in South Florida.