The Tuvalu Meteorological Service (TMS) is the principal meteorological observatory of

Tuvalu Tuvalu ( ) is an island country in the Polynesian subregion of Oceania in the Pacific Ocean, about midway between Hawaii and Australia. It lies east-northeast of the Santa Cruz Islands (which belong to the Solomon Islands), northeast of Van ...

and is responsible for providing weather services to the

islands of Tuvalu Tuvalu consists of nine separate islands: six atolls and three reef islands. An atoll typically consists of several motus: Tuvalu has a total of 124 islands and islets. Each island is surrounded by a coral reef. The soils of Tuvalu's islands are ...

. A meteorological office was established on

Funafuti Funafuti is an atoll, comprising numerous islets, that serves as the capital of Tuvalu. As of the 2017 census, it has a population of 6,320 people. More people live in Funafuti than the rest of Tuvalu combined, with it containing approximately 6 ...

at the time the islands of Tuvalu were administered as parts of the

Gilbert and Ellice Islands The Gilbert and Ellice Islands (GEIC as a colony) in the Pacific Ocean was part of the British Empire from 1892 to 1976. It was a British protectorate, protectorate from 1892 to 12 January 1916, and then a crown colony, colony until 1 January 1 ...

colony of the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...

. The meteorological office is now an agency of the government of Tuvalu. The main observational office is on

. TMS operates outstations on Nanumea, Nui and Niulakita. TMS operates or monitors: 4 synoptic stations; 5 rainfall stations; 1 upper air research program; 1 tide gauge with

Tsunami A tsunami ( ; from , ) is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions and underwater explosions (including detonations, ...

warning system; 1 Continuous

Global Positioning System The Global Positioning System (GPS) is a satellite-based hyperbolic navigation system owned by the United States Space Force and operated by Mission Delta 31. It is one of the global navigation satellite systems (GNSS) that provide ge ...

(CGPS) station; 1 seismic station. The TMS publishes weather forecasts, warnings as to tropical cyclones, weather charts and weather satellite images on its website, with weather forecasts and storm warnings also broadcast by the Tuvalu Media Corporation, which operates Radio Tuvalu.

History

The meteorological office on Funafuti was established in 1951 under the auspices of the South Pacific Air Transport Council (SPATC). An upper air observation programme was established in 1960. After the dissolution of SPATC in 1979, the Meteorological Service of New Zealand Limited supported the upper air programme until the TMS assumed responsibility for the programme, with continuing support by the New Zealand Ministry of Foreign Affairs and Trade (MFAT)/ NZAID. The TMS works with the New Zealand MetService, the Fiji Meteorological Service, the Australian

Bureau of Meteorology The Bureau of Meteorology (BOM or BoM) is an executive agency of the Government of Australia, Australian Government that is responsible for providing Weather forecasting, weather forecasts and Meteorology, meteorological services to Australia a ...

Geoscience Australia Geoscience Australia is a statutory agency of the Government of Australia that carries out geoscientific research. The agency is the government's technical adviser on aspects of geoscience, and serves as the repository of geographic and geolo ...

, the

United States Geological Survey The United States Geological Survey (USGS), founded as the Geological Survey, is an agency of the U.S. Department of the Interior whose work spans the disciplines of biology, geography, geology, and hydrology. The agency was founded on Mar ...

and the

National Weather Service The National Weather Service (NWS) is an Government agency, agency of the Federal government of the United States, United States federal government that is tasked with providing weather forecasts, warnings of hazardous weather, and other weathe ...

. Ms Hilai Vavae retired as Director of the Tuvalu Met Service in 2014.

Climatology of Tuvalu

Tuvalu participates in the operations of the Secretariat of the Pacific Regional Environment Programme (SPREP). The climate of the Pacific region at the equator is influenced by a number of factors; the science of which is the subject of continuing research. The SPREP described the climate of Tuvalu as being: The sea level in Tuvalu varies as a consequence of a wide range of atmospheric and oceanographic influences. The 2011 report of the ''Pacific Climate Change Science Program'' published by the Australian Government, describes a strong zonal (east‑to-west) sea-level slope along the equator, with sea level west of the International Date Line (180° longitude) being about a half metre higher than found in the eastern equatorial Pacific and South American coastal regions. The trade winds that push surface water westward create this zonal tilting of sea level on the equator. Below the equator a higher sea level can also be found about 20° to 40° south (Tuvalu is spread out from 6° to 10° south). The ''Pacific Climate Change Science Program'' Report (2011) describes the year-by-year volatility in the sea-level as resulting from the El Niño–Southern Oscillation (ENSO): The Pacific (inter-)decadal oscillation is a climate switch phenomenon that results in changes from periods of La Niña to periods of El Niño. This has an effect on sea levels. For example, in 2000 there was a switch from periods of downward pressure of El Niño on sea levels to an upward pressure of La Niña on sea levels, which upward pressure causes more frequent and higher high tide levels. The Perigean spring tide (often called a king tide) can result in seawater flooding low-lying areas of the islands of Tuvalu.

Role of the Tuvalu Meteorological Service

The purpose of the meteorological programmes operated by the TMS is to gather data in the tropical western Pacific so as to work to achieve “accurate production of weather forecasts, seasonal and interannual climate forecasting (ENSO predictions), and understanding changes in climate and sea level for Tuvalu and its neighbouring Pacific Islands. Tuvalu lies across a known development region for tropical cyclones and ENSO activity. It provides crucial data to global weather, climate modelling and forecasting centres. It also provides the key data used for tropical cyclone and ENSO forecasting.”

Meteorological programmes

The TMS operates 2 meteorological programmes (surface observation programme and upper air programme) and hosts other climatological research projects.

Surface observations

The TMS carries out ground level observations of various weather elements. This data is shared with collaborating partners in the World Meteorological Organization - World Weather Watch (WWW), the

Global Climate Observing System The Global Climate Observing System (GCOS) was established in 1992 as an outcome of the Second World Climate Conference, to ensure that the observations and information needed to address climate-related issues are obtained and made available to ...

(GCOS) and the Global Earth Observation System of Systems (GEOSS).

Upper air observations

The upper air observation programme in Funafuti makes radiosonde observations to collect upper air weather for weather forecasting and research. The radiosonde observations use a small, expendable instrument package is suspended below a wide balloon filled with

hydrogen Hydrogen is a chemical element; it has chemical symbol, symbol H and atomic number 1. It is the lightest and abundance of the chemical elements, most abundant chemical element in the universe, constituting about 75% of all baryon, normal matter ...

helium Helium (from ) is a chemical element; it has chemical symbol, symbol He and atomic number 2. It is a colorless, odorless, non-toxic, inert gas, inert, monatomic gas and the first in the noble gas group in the periodic table. Its boiling point is ...

. As the radiosonde rises at about 300 meters/minute (1,000 ft/min), sensors on the radiosonde measure profiles of pressure, temperature, and relative humidity. These sensors are linked to a battery-powered radio transmitter that sends the sensor measurements to a ground receiver. By tracking the position of the radiosonde in flight, information on wind speed and direction are also obtained. The data is shared with Regional Specialized Meteorological Centers (RSMCs) in Nadi,

Wellington Wellington is the capital city of New Zealand. It is located at the south-western tip of the North Island, between Cook Strait and the Remutaka Range. Wellington is the third-largest city in New Zealand (second largest in the North Island ...

Brisbane Brisbane ( ; ) is the List of Australian capital cities, capital and largest city of the States and territories of Australia, state of Queensland and the list of cities in Australia by population, third-most populous city in Australia, with a ...

Melbourne Melbourne ( , ; Boonwurrung language, Boonwurrung/ or ) is the List of Australian capital cities, capital and List of cities in Australia by population, most populous city of the States and territories of Australia, Australian state of Victori ...

and

Honolulu Honolulu ( ; ) is the List of capitals in the United States, capital and most populous city of the U.S. state of Hawaii, located in the Pacific Ocean. It is the county seat of the Consolidated city-county, consolidated City and County of Honol ...

. The weather modelling carried out by the RSMCs enables more accurate forecasts to be prepared for Tuvalu and for the tropical western Pacific.

Tropical cyclone prediction

The meteorological observations of the TMS are shared with other regional agencies that attempt to predict how many

tropical cyclone A tropical cyclone is a rapidly rotating storm system with a low-pressure area, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain and squalls. Depending on its locat ...

s and severe tropical cyclones will develop within the Southern Pacific. New Zealand's National Institute of Water & Atmospheric Research (NIWA) and collaborating agencies including the Meteorological Service of New Zealand and Pacific Island National Meteorological Services (including the TMS) issue the "Island Climate Update Tropical Cyclone Outlook" for the Pacific. This forecast attempts to predict how many tropical cyclones and severe tropical cyclones will develop within the Southern Pacific between 135°E and 120°W as well as how many will affect a particular island nation. The Fiji Meteorological Service, while collaborating with NIWA and partners, also publishes its own seasonal forecast for the South Pacific basin between 160°E and 120°W. The data collected by the regional meteorological agencies is provided to the World Meteorological Organisation, which publishes current tropical cyclone information for the South-West Pacific Ocean.

Other climatological research programmes and projects

The TMS also hosts other scientific and research programmes, which involves the TMS monitoring: * The tide gauge, which was installed in 1978 by the

University of Hawaii A university () is an educational institution, institution of tertiary education and research which awards academic degrees in several Discipline (academia), academic disciplines. ''University'' is derived from the Latin phrase , which roughly ...

. * The SEAFRAME tide gauge, which is modern Aquatrak acoustic gauge installed in 1993 by the Australian National Tidal Facility (NTF) as part of the AusAID-sponsored South Pacific Sea Level and Climate Monitoring Project. TMS participates in research projects including: * South Pacific Sea Level and Climate Monitoring Project (SPSLCMP): which was developed in 1991 as an Australian Government response to “concerns raised by member countries of the South Pacific Forum over the potential impacts of human-induced global warming on climate and sea levels in the Pacific”. This project is conducted in conjunction with

(GA), which installed a Continuous

(CGPS) station at the TMS office. * Climate and Ocean Monitoring and Prediction (COMP) project: established by Australian Bureau of Meteorology as part of the Pacific Islands Climate Prediction Project (PI-CPP). * Seasonal Climate Outlooks in Pacific Island Countries (SCOPIC) project: established by Australian Bureau of Meteorology, which is a “

decision support system A decision support system (DSS) is an information system that supports business or organizational decision-making activities. DSSs serve the management, operations and planning levels of an organization (usually mid and higher management) and ...

for generating probabilistic predictions (seasonal climate outlooks) for rainfall, temperature or other climate related parameters”.

Membership of meteorological and geoscience organizations

TMS participates in the activities of: * The World Meteorological Organization (WMO). * The South Pacific Applied Geoscience Commission (SOPAC). * The Secretariat of the Pacific Regional Environment Programme (SPREP). * SOPAC / SPREP / WMO sponsored meetings of Regional Meteorological Service Directors and Regional Disaster Managers. * The Pacific Meteorological Council (PMC): is a specialized subsidiary body of SPREP, established in July 2011 at the 14th Regional Meteorological Services Directors meeting in

Majuro Majuro (; Marshallese language, Marshallese: ' ) is the Capital city, capital and largest city of the Marshall Islands. It is also a large coral atoll of 64 islands in the Pacific Ocean. It forms a legislative district of the Ratak Chain, Ratak ( ...

Marshall Islands The Marshall Islands, officially the Republic of the Marshall Islands, is an island country west of the International Date Line and north of the equator in the Micronesia region of the Northwestern Pacific Ocean. The territory consists of 29 c ...

on a bi-annual basis to facilitate and coordinate the scientific and technical programme and activities of the Regional Meteorological Services. * The Online Climate Outlook Forum (OCOF): also known as the Pacific Islands online Climate Outlook Forum (PICOF) that is a monthly discussion among Pacific Island National Meteorological Services (NMS) and the Australian Bureau of Meteorology. The OCOF assists in the implementation of the SCOPIC project and the Climate Adaptation Projects that are supported by the Australian Bureau of Meteorology.