Current weather satellites

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This is an image of a weather satellite from 2010. Credit: Greg Goebel.

This course gives an overview of the current weather satellite systems in operation today and studies other satellites of the same series that were launched and operated in the past.

Overview[edit]

The 1960s heralded the first weather satellites and quickly proved their usefulness. By the 1970s clear trends were already established with the USA settling on the use of both Geostationary and Polar orbiting satellites. During this period, the European Space Agency (ESA) developed their own series of satellites, the Meteosats which were geostationary. Other countries later joined in to develop and launch their own systems.

Current Coverage[edit]

For the past decade or even more, the configuration of operational satellites has been fairly stable. It consists of a set of equatorial geostationary satellites giving complete coverage of the entire globe and then a further set of polar orbital satellites that typically yield global coverage twice a day, twelve hours apart.

There are usually five geostationary satellites, two from the US, covering that region, one from Europe covering that slice of the globe and then one from India, and finally one from Japan covering their respective sectors of the Earth. These satellites generally give a full scan of the Earth's disk every 30 minutes or better.

The main drawback with geostationary satellites is that coverage at both polar regions is almost non-existent due to the very low angle of viewing.

A pair of polar orbiting satellites have been provided for many years by the NOAA (USA) agency. These make up for the lack of coverage by the geostationary satellites. This dataset goes back many years.

Meteosat[edit]

This is an image of Meteosat 8 that was launched in 2002. Credit: Norwegian Meteorological Institute.

The are series of geostationary satellites launched by the European Space Agency. There have been two generations of satellites with the current fleet being the Meteosat Second Generation (MSG).

In general the meteosat series of satellites have been placed at 00longitude over Africa and provide a permanent view of the disk of the Earth centered on Africa and including Europe, parts of the eastern Atlantic and western Russia, Middle East and corresponding geographic co-ordinates in the Southern Hemisphere.

As the satellites either failed or went out of operation, they were moved out of these orbital locations to safety or in some cases, the satellites were leased for a few years to other agencies and moved to locations over the Indian Ocean for example.

The operational Meteosat program was transferred from ESA in 1986 to the Eumetsat organization.

Capabilities and Instruments[edit]

The first generation series had approximately 5 km resolution and scans in the Infrared and Water Vapor channels and 2.5 km in Visible wavelenghts. The full Earth disk was scanned roughly every 30 minutes.

In the second generation series the resolution has been improved to 3km and a high resolution mode of 1 km. Scanning frequency is now every 15 mins. The MSG has a new multispectral imager called the Spinning Enhanced Visible and InfraRed Imager (SEVIRI) and this has 12 spectral channels instead of 3 as in the previous system.

Imaging Band Visible (VIS) Water Vapor (WV) Infrared (IR)
Spectral range 0.45 - 1.0 μm 5.71 - 7.1 μm 10.5 - 12.5 μm
Resolution at nadir 2.5 km 5.0 km 5.0 km
Scanning Frequency 30 mins 30 mins 30 mins

Series[edit]

Meteosat First Generation[edit]

Name Launched & Lifetime Located Over Channels
Meteosat-1 Sep 1977 - Oct 1979 Africa, 0° longitude IR, Vis, WV
Meteosat-2 1981 - 1991 Africa, 0° longitude IR, Vis, WV
Meteosat-3 1988-1995 Africa, 0° longitude IR, Vis, WV
Meteosat-4 1989 - 1995 Africa, 0° longitude IR, Vis, WV
Meteosat-5 1991 - 2007 Africa, 10°W longitude IR, Vis, WV
Meteosat-6 1993 - 2006 Africa, 0° longitude IR, Vis, WV
Meteosat-7 1997 - 2008 (planned) Africa, 0° longitude IR, Vis, WV

Meteosat Second Generation (MSG)[edit]

This is a significantly enhanced follow-on system to the previous generation of Meteosat and is designed to last until 2018.

Name Launched Status Located Over Channels
Meteosat-8 Jan 29, 2004 Operational Africa IR, Vis, WV
Meteosat-9 Dec 21, 2005 Operational Africa IR, Vis, WV

NOAA Weather Satellites[edit]

This is an image of the NOAA meteorological satellite ITOS (1970). Credit: Pline.
The image shows the Suomi National Polar-orbiting Partnership operated by NOAA (2010). Credit: Ryan Zuber, Scientific Visualization Studio, NASA.

There are a series of polar orbiting satellites launched by NOAA. They are usually placed in an orbit inclined at 89° to equatorial plane at an altitude of approximately 800 km, giving an orbital period of about 90 minutes. At this inclination, the orbit precesses about the globe and evidently covers the entire Earth every x days.

The most recent is the Suomi National Polar-orbiting Partnership satellite operated by NOAA and launched in 2011.

Capabilities and Instruments[edit]

This series has approximately 1 km resolution and scans in the Infrared and Visible wavelenghts. The main instrument is the AVHRR scanner. The improved resolution comes about as a result of a much lower orbit (~800km) as opposed to the 36,000 km for geostationary orbits.

Series[edit]

Name Launched Status Scanner
NOAA-17 Jan 29, 2004 Operational AVHRR (??)
NOAA-18 Dec 21, 2005 Operational AVHRR (??)

GOES Weather Satellites[edit]

An artist's rendering of the GOES-15 satellite in orbit is shown. Credit: Marc Selinger, Boeing.

These are Geostationary Operational Environmental Satellite (GOES) system developed by the NASA and NOAA. There have been two main series, GOES and GOES-NEXT. The GOES satellites are operated in pairs nominally called GOES-East at 750 longitude and GOES-West at 1350 longitude in order to give full coverage of the continous US.

The GOES series satellites were designated by a letter until launch and then when operational were assigned a number. For example GOES-K was renamed GOES-10 upon reaching orbit.

The first GOES generation of satellites was launched in Oct, 1975 until 1994, when the second generation[factual?] of GOES I-M was introduced. GOES-15 is at right from 2011.

Capabilities and Instruments[edit]

This series has approximately 1 km resolution and scans in the Infrared and Visible wavelenghts. It scans the full disk of the Earth rougly every 30 minutes.

Series[edit]

First Generation[edit]

Name Launched & Lifetime Located Over Channels
GOES-1 Oct 1975 -Mar 1985 Indian Ocean  ??
GOES-2 Jun 1977 - 1993 600 West VISSR Scanner
GOES-3 1978 - 1993 600 West VISSR Scanner
GOES-4 Sep 1980 - Nov 1988 1350 West VISSR Scanner
GOES-5 May 1981 - July 1990 750 West VISSR Scanner
GOES-6 Apr 1983 - 1989 1360 West VISSR Scanner
GOES-G May 1986 lost in launch failure N/A N/A
GOES-7 Apr 1983 - 1996 (??) 750 West VISSR Scanner

Second Generation[edit]

This series covers GOES I-M and are the current satellites of this series in use.

Name Launched & Lifetime Located Over Channels
GOES-8 Apr 1994 - Present (??) Indian Ocean  ??
GOES-9 May 1995 - 1998 1350 West  ??
GOES-10 Apr 1997 - Present (??) 1050 West  ??
GOES-11 Apr 1983 - Present  ??  ??

US Military Weather Satellites[edit]

A group from the Army Signal Corps developed the nation's first weather satellite called the Television Infrared Observation Satellite (TIROS). Credit: NASA.

The US military has the Defense Meteorological Satellite Program (DMSP). This has been a long running program from the mid 1960s. The DMSP series are known as Low Earth Orbit (LEO) satellites. This class of orbit generally includes polar orbiting satellites.

Russian[edit]

This is a mockup of the Russian meteorological satellite Cosmos 122 (1966). Credit: Pline.

The Russians have launched numerous weather satellites over the years. Their weather satellites of interest are the Meteor-3M -polar orbiting satellites and GOMS geostationary series.

GOMS[edit]

There was only one launch of satellite in this series which was GOMS-1 on 31st Oct 1994. Apparently the troubled spacecraft could not be put into use and the whole project was finally cancelled.

Meteor[edit]

This is an image of the Russian meteorological satellite Meteor-М"№1 from 2009. Credit: El Salvador.

Indian[edit]

Information on the Indian weather satellite program seems to be quite hard to determine, but they have had a space program going back to the 1980s and have tended to use multi-purpose satellites. The INSAT series for example can have different roles from one launch to the next, although presumably they satellite payloads are quite different.

The most recent India weather satellite appears to be geostationary INSAT 3A satellite launched on April 9th, 2003.

Name Launched & Lifetime Located Over Channels
INSAT-1A 10th Apr 1982 - late 1982 India, 74° East longitude VHRR (Vis res 2.7km, IR res 11km, 30 mins)
INSAT-1B 31st Aug 1983 - India, 74° East longitude VHRR (Vis res 2.7km, IR res 11km, 30 mins)
INSAT-1C 21st Jul 1988 - India, 94° East longitude VHRR (Vis res 2.7km, IR res 11km, 30 mins)
INSAT-1D 12th Jun 1990 - India, 83.1° East longitude VHRR (Vis res 2.7km, IR res 11km, 30 mins)
INSAT-2A 12th Jun 1990 - India, 74° East longitude  ??
INSAT-2B 22nd Jul 1993 - India, 93.5° East longitude  ??
INSAT-2D 3rd Jun 1997 - India, 74.1° East longitude  ??
INSAT-2E 2nd Apr 1999 - India, 83° East longitude VHRR (Vis res 2km, WV res 8km, ??)
INSAT-3A 9th Apr 2003 India, 93.5° East longitude Vis, WV, IR

Japanse[edit]

The Japanese geostationary meteorological satellites (GMS) are known as Himawari, numbers 1 - 5. Credit: masamic.

The Japanse have operated geostationary satellites over Japan since 1977 when the first of the GMS series was launched. The main meteorlogical instrumentation was the Visible and Infrared Spin Scan Radiometer (VISSR)

Name Launched & Lifetime Located Over Channels
GMS-1 14th Jul 1977 Pacific Ocean, 140° East longitude VISSR
GMS-2 10th Aug 1981 - 2007? Pacific Ocean, 140° East longitude VISSR
GMS-3 3rd Aug 1984 - 2007? Pacific Ocean, 140° East longitude VISSR
GMS-4 6th Sep 1989 - 2007? Pacific Ocean, 140° East longitude VISSR
GMS-5 18th Mar 1995 - 2007? Pacific Ocean, 140° East longitude VISSR

Chinese meteorological satellites[edit]

This is a model of the Fengyun-2 meteorological satellite in the Shanghai Science & Technology Museum. Credit: Jakub Hałun.

French meteorological satellites[edit]

The image shows the French meteorological satellite EOLE (1971). Credit: Pline.

Data Access[edit]

Satellite Receiving and Data Centers[edit]

For the NOAA polar orbiting satellites, it is possible to get your own receiver and receive the data as it is broadcast as the satellite passes overhead daily.

For these receiving stations, the satellite may be programmed to dump data from disk from other areas down to them.

  • USA (where??)
  • Darmstadt, Germany
  • Dundee, Scotland

Glossary[edit]

  • NOAA -National Oceanic and Atmospheric Administration

Lectures[edit]

Many of these lectures introduce observational astronomies that have focused on Earth.

Quizzes[edit]

See Also[edit]

Topic:Weather_satellites Topic:Remote_sensing