Weather satellite

While primarily used to detect the development and movement of storm systems and other cloud patterns, meteorological satellites can also detect other phenomena such as city lights, fires, effects of pollution, auroras, sand and dust storms, tornadoes, snow cover, ice mapping, boundaries of ocean currents, and energy flows. Other types of environmental information are collected using weather satellites. Weather satellite images helped in monitoring the volcanic ash cloud from Mount St. Helens and activity from other volcanoes such as Mount Etna. Smoke from fires in the western United States such as Colorado and Utah have also been monitored.

El Niño and its effects on weather are monitored daily from satellite images. The Antarctic ozone hole is mapped from weather satellite data. Collectively, weather satellites flown by the U.S., China, Europe, India, Russia, and Japan provide nearly continuous observations for a global weather watch.

History

1950s

As early as 1946, the idea of cameras in orbit to observe the weather was being developed. This was due to sparse data observation coverage and the expense of using cloud cameras on rockets. By 1958, the early prototypes for TIROS and Vanguard (developed by the Army Signal Corps) were created. The first weather satellite, Vanguard 2, was launched on February 17, 1959. It was designed to measure cloud cover and resistance, but a poor axis of rotation and its elliptical orbit kept it from collecting a notable amount of useful data. The Explorer 6 and Explorer 7 satellites also contained weather-related experiments.

1960s

The first weather satellite to be considered a success was TIROS-1, launched by NASA on April 1, 1960. TIROS operated for 78 days and proved to be much more successful than Vanguard 2. Other early weather satellite programs include the 1962 Defense Satellite Applications Program (DSAP) and the 1964 Soviet Meteor series.

TIROS paved the way for the Nimbus program, whose technology and findings are the heritage of most of the Earth-observing satellites NASA and NOAA have launched since then. Beginning with the Nimbus 3 satellite in 1969, temperature information through the tropospheric column began to be retrieved by satellites from the eastern Atlantic and most of the Pacific Ocean, which led to significant improvements to weather forecasts.

The ESSA and NOAA polar orbiting satellites followed suit from the late 1960s onward. Geostationary satellites followed, beginning with the ATS and SMS series in the late 1960s and early 1970s, then continuing with the GOES series from the 1970s onward. Polar orbiting satellites such as QuikScat and TRMM began to relay wind information near the ocean's surface starting in the late 1970s, with microwave imagery which resembled radar displays, which significantly improved the diagnoses of tropical cyclone strength, intensification, and location during the 2000s and 2010s.

1970s

In Europe, the first Meteosat geostationary operational meteorological satellite, Meteosat-1, was launched in 1977 on a Delta launch vehicle. The satellite was a spin-stabilised cylindrical design, 2.1 m in diameter and 3.2 m tall, rotating at approx. 100 rpm and carrying the Meteosat Visible and Infrared Imager (MVIRI) instrument. Successive Meteosat first generation satellites were launched, on European Ariane-4 launchers from Kourou in French Guyana, up to and including Meteosat-7 which acquired data from 1997 until 2017, operated initially by the European Space Agency and later by the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT).

Japan has launched nine Himawari satellites beginning in 1977.

1980s

Starting in 1988 China has launched twenty-one Fengyun satellites.

2000s

The Meteosat Second Generation (MSG) satellites - also spin stabilised although physically larger and twice the mass of the first generation - were developed by ESA with European industry and in cooperation with EUMETSAT who then operate the satellites from their headquarters in Darmstadt, Germany with this same approach followed for all subsequent European meteorological satellites. Meteosat-8, the first MSG satellite, was launched in 2002 on an Ariane-5 launcher, carrying the Spinning Enhanced Visible and Infrared Imager (SEVIRI) and Geostationary Earth Radiation Budget (GERB) instruments, along with payloads to support the COSPAS-SARSAT Search and Rescue (SAR) and ARGOS Data Collection Platform (DCP) missions. SEVIRI provided an increased number of spectral channels over MVIRI and imaged the full-Earth disc at double the rate. Meteosat-9 was launched to complement Meteosat-8 in 2005, with the second pair consisting of Meteosat-10 and Meteosat-11 launched in 2012 and 2015, respectively.

In 2006, the first European low-Earth orbit operational meteorological satellite, Metop-A was launched into a Sun-synchronous orbit at 817 km altitude by a Soyuz launcher from Baikonur, Kazakhstan. This operational satellite - which forms the space segment of the EUMETSAT Polar System (EPS) - built on the heritage from ESA's ERS and Envisat experimental missions, and was followed at six-year intervals by Metop-B and Metop-C - the latter launched from French Guyana in a "Europeanised" Soyuz. Each carry thirteen different passive and active instruments ranging in design from imagers and sounders to a scatterometer and a radio-occultation instrument. The satellite service module is based on the SPOT-5 bus, while the payload suite is a combination of new and heritage instruments from both Europe and the US under the Initial Joint Polar System agreement between EUMETSAT and NOAA.

2010s

The DSCOVR satellite, owned by NOAA, was launched in 2015 and became the first deep space satellite that can observe and predict space weather. It can detect potentially dangerous weather such as solar wind and geomagnetic storms. This is what has given humanity the capability to make accurate and preemptive space weather forecasts since the late 2010s.

2020s

The Meteosat Third Generation (MTG) programme launched its first satellite, Meteosat-12, in 2022, and featured a number of significant changes over its predecessors in support of its mission to gather data for weather forecasting and climate monitoring. The MTG satellites are three-axis stabilised rather than spin-stabilised, giving greater flexibility in satellite and instrument design. The MTG system features separate Imager and Sounder satellite models that share the same satellite bus, with a baseline of three satellites - two Imagers and one Sounder - forming the operational configuration.

The imager satellites carry the Flexible Combined Imager (FCI), succeeding MVIRI and SEVIRI to give even greater resolution and spectral coverage, scanning the full Earth disc every ten minutes, as well as a new Lightning Imager (LI) payload. The sounder satellites carry the Infrared Sounder (IRS) and Ultra-violet Visible Near-infrared (UVN) instruments. UVN is part of the European Commission's Copernicus programme and fulfils the Sentinel-4 mission to monitor air quality, trace gases and aerosols over Europe hourly at high spatial resolution. Two MTG satellites - one Imager and one Sounder - will operate in close proximity from the 0-deg geostationary location over western Africa to observe the eastern Atlantic Ocean, Europe, Africa and the Middle East, while a second imager satellite will operate from 9.5-deg East to perform a Rapid Scanning mission over Europe. MTG continues Meteosat support to the ARGOS and Search and Rescue missions. MTG-I1 launched in one of the last Ariane-5 launches, while MTG-S1 launched in 2025 on a SpaceX Falcon 9, carrying the Sentinel-4 instrument for the EC's Copernicus programme. MTG-I2 will launch in August 2026 on an Ariane-6, the first instance of using an Ariane-62 variant to launch a satellite into geostationary orbit. A further triplet of MTG satellites is planned for launch in the 2030s, continuing the MTG mission into the early 2040s.

A second generation of Metop satellites (MetOp-SG) has also begun deployment, with the first satellite (Metop-SGA1) launched in 2025 on an Ariane-62, carrying the Sentinel-5 instrument for the EC's Copernicus programme. The Metop-SG space segment also has two satellite models based on a common platform, with one satellite of each model operated as a pair required to complete the full instrument complement of the operational baseline for EUMETSAT's EPSSG mission. The second satellite, and first of the B-models (Metop-SGB1), will launch on Ariane-6 in late 2026. Two further pairs of Metop-SG satellites are planned for launch in the early- and late-2030s, continuing the EPSSG mission into the 2040s.