Federated States of Micronesia

Explore historical and projected climate data, climate data by sector, impacts, key vulnerabilities and what adaptation measures are being taken. Explore the overview for a general context of how climate change is affecting Federated States of Micronesia.

Country Summary

This page presents high-level information for Federated States of Micronesia's climate zones and its seasonal cycle for mean temperature and precipitation for the latest climatology, 1991-2020. Climate zone classifications are derived from the Köppen-Geiger climate classification system, which divides climates into five main climate groups divided based on seasonal precipitation and temperature patterns. The five main groups are A (tropical), B (dry), C (temperate), D (continental), and E (polar). All climates except for those in the E group are assigned a seasonal precipitation sub-group (second letter).  Climate classifications are identified by hovering your mouse over the legend. A narrative overview of Federated States of Micronesia's country context and climate is provided following the visualizations.

Köppen-Geiger Climate Classification, 1991-2020
  • Af
  • Am
  • As/Aw
  • BWh
  • BWk
  • BSh
  • BSk
  • Csa
  • Csb
  • Csc
  • Cwa
  • Cwb
  • Cwc
  • Cfa
  • Cfb
  • Cfc
  • Dsa
  • Dsb
  • Dsc
  • Dsd
  • Dwa
  • Dwb
  • Dwc
  • Dwd
  • Dfa
  • Dfb
  • Dfc
  • Dfd
  • ET
  • EF

As part of the larger island grouping of Micronesia, the Republic of the Marshall Islands (RMI) consists of two groups of atolls and islands in the Central North Pacific Ocean about 3,200 kilometres (km) away from both Honolulu and Tokyo. 22 of the 29 atolls and four out of the five small raised coral islands are inhabited; the atoll islands are rarely more than 200 metres (m) in width and almost all of the land is below 2 m.1 The Marshall Islands has a moist, tropical climate, heavily influenced by the north-east trade wind belt. Annual rainfall varies considerably from north to south within the archipelago, with atolls in the south receiving 300–340 centimetres  (cm) rainfall annually, perhaps as much as 3 times more than northern atolls. The average annual temperature and monthly means are generally consistent at around 27°C, with a maximum daily variation of about 7°C.1 Most of the RMI’s population of approximately 58, 700 persons (2019), live in the capital city, Majuro. 92% of the population identifies as Marshallese, and the official language, Marshallese, is spoken by more than 98% of people.

The RMI has a unique and close relationship with the United States (US). In 1944, the US gained military control of the country from Japan, and assumed administrative control of the country under United Nations auspices as part of the Trust Territory of the Pacific Islands following the end of World War II. In 1983, the RMI signed a Compact of Free Association with the US and gained independence in 1986 with the Compact’s entry into force. Under this Compact, the US provided defence, subsidies and access to social services, and in 2003, this agreement was amended to provide around US$70 million each year over the period 2004–2024. Since independence, external assistance and grants have formed 60% of government revenue.

In addition to this dependence on external assistance, the RMI faces a variety of social vulnerabilities, much like many other small island developing states (SIDS). Issues of geographical remoteness, a small sparsely-distributed population, distance to international import and export markets, and associated high costs of transportation, small domestic market, challenges of achieving economies of scale of production, and very high energy costs, as well as few natural resources, all hinder economic development potential. The RMI is heavily reliant on imports – agricultural production is primarily subsistence-based, and small-scale industry is limited to handicrafts, tuna processing and copra. Although tourism is not a major source of foreign exchange, as it is in other Pacific island countries, the industry accounts for about 10% of the local labour market. While many official basic indicator data are not available for the RMI, using 2011 census data it was estimated that 37% of the total population live below the “basic-needs income line”. While 30% of residents in the two main urban centres (Majuro and Ebeye) are estimated below this line, these numbers could double in the outer islands. Such deepening poverty, amidst “growing concerns over high unemployment, financial hardship, hunger and poor nutrition”, are noted in the context of a vulnerability to “transnational threats, natural disasters, and the potential effects of climate change”. 

The Marshall Islands face a high risk of cyclones, and the low-lying islands are susceptible to coastal floods and tsunamis.5 Extreme heat and drought conditions have also recently affected the islands. In late 2015/early 2016, below average rainfall, exacerbated by El Niño, induced local drought conditions and water shortages. EM-DAT data estimates that the drought affected more than half the population, with resulting economic damages estimated at just under US$5 million. While this event remains the most severe disaster for the country, the potential for disaster risk in the RMI is high due to the combination of economic and physical vulnerability, and the islands’ proneness to natural hazards (it is also noted that previous nuclear testing on some of the atolls have made them uninhabitable7), and is further exacerbated by climate change and variability. The risks faced by the Marshall Islands have been set out in several communications to the United Nations, including republic’s Second National Communication to the UNFCCC (2015); the RMI is also noted for being the first country to submit its ambitious Second Nationally Determined Contribution (2020) to the Paris Climate Agreement.