Calipso — Wikipedia
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For homonymous items, see Calipso.
Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observations
View of artist from the Calipso satellite.
| CALIOP | Lidar |
|---|---|
| WFC | Large field camera |
| IIR | Infrared radiometer |
Calipso ( Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation ) is a small earth observation satellite, 635 kg , Franco-American (CNES and NASA) launched in 2006. Its instruments make it possible to study the radiative impacts of clouds and aerosols. The objective is to improve the mathematical model of climate evolution. Calipso works in tandem with the Cloudsat radar satellite in a constellation satellites, the A-Train, devoted to the observation of clouds, aerosols and the water cycle. The main instrument of Calipso is a Lidar which allows to measure with precision the characteristics of the different stages of the atmosphere. The mission of an initial duration of 3 years is extended in 2009. This spatial mission is part of the Earth Observing System program which brings together a set of satellites from NASA responsible for collecting data on long periods on the surface of the Earth, The biosphere, the earth’s atmosphere and the earth oceans.
The three -dimensional modeling of climatic processes on the planet’s scale is necessary to allow a prediction of climate change which today constitutes an important societal issue. In order for this modeling to be correct it is necessary to have an exact representation of the processes involved within the atmosphere and the interactions between the atmosphere, the ocean and the biosphere. At the time of the design of Calipso, the most important source of imprecision was the radiative impact of clouds and aerosols. To have a better knowledge of the radiative assessment of the earth, it is necessary to measure the radiative flow on the top of the atmosphere and on the ground but also at different heights in the atmosphere [ first ] .
The passive measurement instruments that are content to analyze the light reflected by the clouds are not precise enough to achieve these objectives. The Calipso satellite takes a Lidar which includes a laser emitting short high intensity light pulses and a telescope which makes it possible to collect the returned light. The analysis of this makes it possible to deduce the composition of the different layers of the atmosphere [ 2 ] .
Calipso is part of the A-Rain, a constellation of several Franco-American satellites which allow a temporally and spatially co-logged study of the vast majority of the useful climate and meteorological parameters for understanding the climate. The measurements made by the Calipso Lidar can thus be compared to those of the Cloudsat satellite which follows Calipso on the same orbit at a distance. Cloudsat takes away a “cloud radar” which constitutes another active active measurement instrument of the LIDAR. Calipsto satellite is developed to meet the following objectives [ 3 ] :
- Measure the direct and indirect effect of aerosols.
- Specify radiative flows by improving a factor 2 the accuracy of long wave radiative flow estimates.
- Arrange the characteristics of fine cirrus, polar clouds and multi -layer clouds.
- Contribute to the general objectives of synergy modeling with the data collected by the parasol, Aqua and Cloudsat du A-Train satellites.
To fulfill its mission, the satellite is placed on a Héliosynchrone orbit at 700 km altitude with an inclination of 98.2 °.
The satellite and its scientific instruments [ modifier | Modifier and code ]
Calipso uses the PROTUUS minisatellite platform developed by CNES and Alcatel Alenia Space (now Thales Alenia Space) in the Cannes – Mandelieu space center for satellites of a mass of around 500 kg . I am Caliper pusips 635 kg And its deployable solar panels provide 560 watts. TVs allowing the satellite monitoring and remote controls sent to the satellite use an S band link with a 4 kbit/s flow (rising link) and 727 kbit/s (downward connection). The data collected by the measurement instruments are transmitted to the land stations by an X -band link of 80 Mbit/s.
The main instrument of Calipso is Caliop, a retradifood Lidar and comprising two channels (532 Nm and 1064 Nm) equipped with a 1 meter diameter telescope. The other two instruments are a camera operating in visible to large field opening and an infrared imaging radiometer with 3 -channel (IIR). NASA develops the LIDAR and the camera while the CNES supports the radiometer manufactured by SODERN [ 4 ] .
Floor installations (floor segment) include the following 3 main components [ 5 ] :
- The mission scientific mission center is the Atmospheric Sciences Data Center Located at the NASA Langley Research Center; He receives scientific data and distributes them to users.
- the Mission Operations Ground System Also located in Langley is responsible for the global coordination of the mission (Flight in A-Train Training, Monitoring and ordering of the payload) and the reception of scientific data.
- the Satellite Operations Ground System (SOGS) at CNES in Toulouse controls the satellite and the operation of the IIR instrument.
The project was launched in 1998 and the development of the satellite begins in 2001. Calipso is launched the Since the launch base of Vandenberg in California, at the same time as the Cloudsat satellite by a Delta II launcher. The first scientific measures collected were distributed from December 2006. In March 2009, the emergency laser was activated. In 2009, it was also decided to extend the mission.
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