Geography
These remote islands are situated roughly 625 miles (1000km) west of the Ecuadorian coastline. Originally they were named Archipelago de Colon after Christopher Columbus, Cristobal Colon in Spanish. The islands' closest neighbors are Coco Island, 432 miles (720 km) north, Ecuador, and Easter and San Felix Islands, 920 miles (3200 km) south.
The Galapagos Islands are comprised of just under 4900 square miles (7880 km squared) in land mass scattered about 28000 square miles (45000 km squared) of ocean. Isabela is the biggest island at 1771 square miles in dimension. It also boasts the highest elevation at the summit of Wolf Volcano at 5600 feet (1707 meters) above sea level.
Geology of Galapagos Islands
Created by lava rising out of the sea, these volcanic islands consist solely of basalt, giving them their dark color. Below, the Nazca Plate slowly submerges beneath the South American Plate resulting in the frequent volcanic action. The islands of Fernandina, Pinta, Isabela, and Marchena host the most volcanic activity today as well as occasional fumarolic activity.
The volcanoes are predominantly shield volcanoes, giving the islands a cone shape, after years of lava layering. Starting at the seabed they have risen as much as 10,000 ft (3000 m). Some of the volcanoes have a flatter appearance due to an eruption where the lava escapes from fissures, quickly spreading and cooling across the surface.
This archipelago continues to be a highly active volcanic region and has had over 50 eruptions during the last 200 years. There are six volcanoes still considered active, one residing on Fernandina and the other five on Isabela. One of Isabela's volcanoes, Cerro Azul erupted on the last day of May in 2008 and continued for a full week.
Oceanography of the Galapagos
Due to their central latitude and the four converging ocean currents, the islands' subtropical climate supports two seasons: rainy and dry. Thanks to the Antarctic current from the south, the islands enjoy mild temperatures year round. The deceptively named rainy reason, from November to June, is normally marked by clear skies and temperatures between 77-87F (26-30C), with only an occasional rainstorm. Ocean temperatures in the archipelago average 75F (24C) during this time. January through April is the peak visiting season for its warm weather and smooth seas. It is the nesting season for birds, so they are abundant on land.
The temperatures decrease in May and June, but not lower than 72F (23C). The official start of the dry season is July and it continues through to November. Clouds roll in more frequently but there is rarely rain. The water dips to 70F (21C) and is often rougher due to wind. Cooler evenings and cloudy days prompt the use of a light sweater. August and September bring the fewest visitors to the islands. During this time the "Garua" (mists and clouds) frequent the highlands.
