Sea Level Rise: a Picture's Worth a Thousand Words
Evidence of sea level rise on Big Pine Key in the Florida Keys.
Sea level rise. The phrase often conjures up images of torrential storm surges, sea walls failing, and beach houses falling into the sea. But the truth of sea level rise is far more subtle and insidious.
The picture to the left provides a perfect illustration of the impacts of human-caused sea level rise. The landscape in this photo (which was taken on Big Pine Key in Florida) used to look much different. Towering pine trees would have dominated the landscape and cabbage palms and hardwood shrubs would have filled in the under-story (as they still do just a quarter of a mile up the road). This Pine Rockland ecosystem used to dominate this island in the lower keys, but now it is under steady assault from all sides, often by obscured forces.
As it retreats, a barren landscape takes its place, dotted with the petrified remains of long fallen pines and hardwood shrubs. The tree you see growing out of these forest remnants is the salt-water loving colonizer of the tropics, the red mangrove. It is just about the only species of vegetation that can survive here, as this environment represents a migrating and growing transition point between freshwater dependent uplands and saltwater dominated lowlands. The culprit for this transition lies unseen, below the surface -- a migrating flood of salty groundwater encroaching on the thin band of freshwater on which these islands depend (known as the freshwater lens).
This phenomenon has lead local researchers and residents to a startling conclusion: long before the Florida Keys are inundated by rising seas, many of the ecosystems that make up this chain of islands will have already disappeared, and along with them, the wildlife that live there. This new, transitional environment is unsuitable for most species of plants and animals and it may very well become the dominant ecosystem in the keys, at least until they finally fall below the waves of the Caribbean Sea.
This tragedy is line with the insidious reality of climate change. While a great deal of attention is often paid to the catastrophic events it influences (e.g. wildfires, hurricanes, droughts, etc.), a lack of light is often shed on the more widespread damage it is causing to our world. This damage is subtle, slower, and far more sinister. Long before our great cities and wild places are devastated by catastrophic climatic events, they will already have become noxious to many of the inhabitants that call them home.