Union of Concerned Scientists

Introduction Climate Projections Freshwater Resources Agriculture Forestry Coastal Development Tourism & Recreation Human Health Fisheries Unique Habitats FL Resources & Links

Present Climate in Florida

• Florida has a warm-temperate to subtropical climate with occasional winter freezes.
  
  
• It has a distinct wet season in the summer and a dry season in the winter. Rainfall totals can vary widely from year to year.
  
  
• Rainfall is brought by extratropical storms in the winter and thunderstorms and tropical storms in the summer and fall, which can result in substantial flooding and other weather extremes.
  
  
• Tropical storms strike Florida on average every 1-2 years—the highest rate of any state along the Gulf or Atlantic coast.
  
  
• Hurricane frequency varies by decade and is strongly influenced by the El Niño–La Niña cycle.

Projected Climate Changes in Florida
	3-10°F rise in winter lows and 3-7°F rise in summer highs. July heat index-a measure combining temperature and humidity to represent the temperature actually felt—could rise by 10-25°F. The freeze line is likely to move north. Ocean water temperatures are also likely to warm.
	In South Florida, one climate model projects the area to get wetter, while the other projects the area to become drier. However, summer soil moisture—critically important to agriculture and forestry determined by rainfall gains and evaporation losses—is projected to change little in the southern part of the state. On the other hand, rainfall over northern Florida is projected to decrease, with soil moisture projections varying. Where and when dry conditions do increase, the risk of wildfires is likely to increase as well.
	More frequent intense rainfall events are projected, with longer dry periods in between. Hurricane intensity (characterized by maximum wind speeds and rainfall totals) could increase slightly with global warming, although changes in future hurricane frequency are uncertain. Even if storm frequencies and intensities remain constant, the damages from coastal flooding and erosion will increase as sea level rises.
	Sea level will increase at a faster rate over the coming century, rising approximately fifteen inches by the end of the century. Even a relatively small vertical rise in sea level (under one foot) can move the shoreline inland by a substantial distance (several tens of feet) along low-lying, flat coastal areas.
	Temperature and precipitation will continue to vary, in part related to the ENSO (El Niño / Southern Oscillation ) cycle.