Puerto Rico has a tropical climate. Despite its size, several ecosystems are present: coastal and marine, dry forests and rainforests, the Puerto Rican karst, and mountainous areas. Puerto Rico has warmed by more than one degree (F) since the mid 20th century, and the surrounding waters have warmed by nearly two degrees since 1901. According to Puerto Rico's Climate Change Council, key historical climate trends include:
- Annual and monthly average temperatures have increased by 0.012° - 0.014°C per year since 1900.
- San Juan’s observed temperature trend is higher than the rest of the island, with mean temperature increasing by 0.022°C per year since 1900.
- A greater frequency of days with maximum temperature equal to or above 32.2°C and a lower frequency of days with temperature equal to or below 23.9°C has been recorded.
- During 2010 and 2011, about 100 days with temperature equal to or above 32.2°C were observed; this is the same number of days observed per decade during 1900 through 1949.
- The southern region of Puerto Rico has experienced positive trends in annual rainfall while the western and a portion of the northern region showed decreases.
- Negative trends in summer and positive trends in winter have been observed.
- Atlantic tropical storm and hurricane destructive potential as measured by the Power Dissipation Index has increased in association with warming Atlantic sea surface temperatures.
This section provides the options to visualize historical climate data for different timeframes via map and annual cycle chart.