Climate change is already impacting the islands and marine environment of the Caribbean Sea, and will continue to do so, more strongly, in decades to come. Increasing extremes, both in weather events and in general climatic patterns, will weaken ecosystems as they exist now and lead to species change. Agriculture and fisheries have already been negatively affected, and those effects are likely to become more severe.
The Intergovernmental Panel on Climate Change (IPCC), the world authority on climate change science, has found only medium confidence that the frequency and severity of tropical cyclones are increasing. However, recent NOAA work has found the Atlantic basin to be a growing global hotspot for cyclones and hurricanes, with a slowly increasing number of annual named storms.
Global hurricane trends
Atlantic basin cyclone trends.
Storm activity, analogously to sea ice extent, is a very noisy signal, with large year-to-year variations. Climate models agree strongly with the more tentative conclusions of storm counts and energy measurements: the Caribbean is likely to receive more of these cataclysmic storm events in years to come as the world warms. An increase of 2°C/3.6°F will increase storm activity in the Caribbean by as much as four times, some models predict.
Threat levels to Caribbean coral reefs
Sea level rise has increased coastal erosion around many Caribbean islands, a trend which will continue. And in the now-familiar pattern throughout the world’s tropical regions, dry seasons have become drier, and will become drier still; while rainy seasons, though the total amount of rain might increase, will occur in fewer, more intense bursts, and more erratically. Economically, most of the Caribbean nations having been colonies until relatively recent (20th century or slightly earlier) times, their economies are not well-developed or robust enough to deal with the disruption of changing climate patterns and increased storm activity. On the contrary, the ruinous cycle of disaster followed by increased debt load has become the norm.
Jamaican banana plantation after Hurricane Sandy, 2012.
Warming, acidifying oceans pose an existential threat to the region’s 10,000 sq km/3,900 sq mi of coral reefs, 22,000 sq km/8,500 sq mi of mangrove and 33,000 sq km/12,700 sq mi of seagrass beds. In many regions of the Caribbean (such as the south coast of Jamaica) already the reefs are dead, more from human agency (overfishing) than purely climate-related causes. But warming water has caused widespread bleaching and led to invasion by highly destructive species of algae, which prevent fresh coral growth and over time kill the reef community. It has been estimated that up to 60% of the Caribbean’s coral reefs have died due to overfishing and interrelated climate causes such as storm activity, warming and acidifying water.
Tomorrow: introduction to Mexico.
Be brave, and be well.
No comments:
Post a Comment