Climate & marine currents
Located on the equator, the Galapagos Islands have a surprisingly cool, sub-tropical climate. The larger islands with volcanic peaks have a variety of climatic zones. The coastal areas are arid and covered with plants adapted to desert conditions. The highland areas receive moisture almost all year round, which support lush vegetation. Temperatures are determined almost entirely by ocean currents, which are influenced by the trade winds.
There are two seasons, both of which have some precipitation. The Galapagos get an average of ten inches of rain per year, so it is never considered "rainy". Unlike most equatorial regions, the Galapagos are not hot and humid; they lie instead in one of the Pacific's "dry zones" where temperatures remain abnormally low, cooled by upwelling in the sea. The Galapagos cycle through two distinct seasons: the warm/wet season (January to June) and the cool/dry season (July to December).
From June to November, the cold Humboldt Current sweeps northward from the Antarctica . When it reaches the northern tip of Peru , the southeast tradewinds push it toward the Galapagos. This mass of cold water cools the air and creates an inversion layer over the islands. The inversion upsets the usual weather pattern associated with the tropics. While the lowlands are experiencing drought, the highlands receive misty precipitation locally known as "garua" (pronounced gah-ru-ah) season, which means mist in Spanish.
During the months from December to May, the cooling current subside, temperatures rise and the southeast trade winds and the Humboldt Current vanish. Warm waters flow south from Panama . Periods of rain are strong but are of short duration. Temperatures are warm and sunny days outnumber cloudy days. Some years, the flow of warm water is greater than normal and a phenomenon known as "El Nino" results. Surface water temperatures climb higher than usual and rainfall greatly increases. Life on land flourishes, but seabirds and marine life frequently experience extreme breeding failures.
Temperatures |
JAN |
FEB |
MAR |
APR |
MAY |
JUN |
JUL |
AUG |
SEP |
OCT |
NOV |
DEC |
| |
max air temp. |
84 |
86 |
88 |
86 |
82 |
78 |
76 |
74 |
76 |
77 |
78 |
80 |
| |
min air temp. |
70 |
74 |
74 |
72 |
72 |
68 |
66 |
64 |
62 |
64 |
66 |
68 |
| |
avg. sea temp |
74 |
76 |
76 |
76 |
74 |
74 |
72 |
66 |
68 |
70 |
72 |
74 |
| |
avg. rainfall (inches) |
1 |
1 |
2 |
1.5 |
.75 |
.25 |
.50 |
.25 |
.50 |
.25 |
.50 |
.50 |
Water temperatures
May to November at Wolf & Darwin: 74-78 degrees F
May to November in Central Islands : 65-72 degrees F
December to April at Wolf & Darwin: 76-80 degrees F
December to April in Central Islands : 75-78 degrees F