Looking at the Earth from space, the world’s oceans occupy 71% of the planet’s surface area and land occupies 29%. There are three primary oceans – Pacific, Atlantic, and Indian – that comprise 89% of the world’s ocean surface area with the aerial extent of the Pacific Ocean about as large as the Indian and Atlantic oceans combined.

Pacific Ocean Map. The red dots in columns around the equator signify where data is collected from buoys to monitor El Nino - La Nina conditions. These data are sometimes collected by the ship National Ocean and Atmospheric Admiinstration ship KA'IMIMOANA (Ocean Seeker in Hawaiian).

The Pacific Ocean occupies about 46% of the total world ocean area and is home to a wide variety of islands and people that call them home.  Small island states and Pacific Islanders are susceptible to variations in climate. They share climate-linked vulnerabilities such as:

• susceptibility to storm systems, tidal variation, and long-term sea level rise;
• impacts to local hydrology;
• pressures imposed by population density;
• impacts to local species density and distribution; and
• limited natural resources.

This is not to say that each Pacific Island and their inhabitants are impacted in the same manner and degree by climate change. Island to island variations in:

• island geology (i.e., island bedrock of volcanic origin versus that of sedimentary origin);
• relative size and large scale structure of the island (e.g., from relatively high islands such as Hawaii to low-lying atolls such as Majuro);
• extent of reef formation; and
• size of groundwater resources

all regulate how future climate variation will impact Pacific Islands and their inhabitants.