The Earth is a planet. The celestial bodies orbiting the planets are all called satellites. The Moon orbits around the Earth, so the Moon is Earth’s natural satellite. People want to know about the meteorological situation on high and they have launched artificial satellites orbiting the Earth to probe meteorology, called meteorological satellites.
What information can meteorological satellites fly at an altitude of hundreds, thousands, even tens of thousands of kilometers? It also has to see what the satellite is equipped with.
In general, the purpose of launching meteorological satellites is to probe the texture of the upper atmosphere composition, cosmic rays, solar radiation, and the properties and effects of solar particles in the atmosphere, the Earth’s magnetic field in the atmosphere, observing from above clouds, rain, storms, etc.
The atmospheric composition texture includes the state of temperature, density, and pressure of the atmosphere and its variation with height. In the past, it was only based on some overhead phenomena (such as polar light, meteors, etc.) to speculate; after having meteorological satellites, it was measured directly.
Cosmic rays, solar radiation, and solar microspheres are important factors that influence the upper and lower atmospheres. The weather changes in the air layer below 10 km altitude, such as temperature, composition, motion, and water vapor distribution, are all related to.
The upper atmosphere is the gateway to cosmic rays. Solar radiation and particles emitted from the Sun enter the Earth through the atmosphere. Knowing their properties and effects on the upper reaches of the atmosphere will know how the atmosphere’s upper atmosphere will affect the weather variation in the lower atmosphere.
That is conducive to discovering the changing law of weather more deeply to forecast the weather better.
The ionosphere is mainly composed of solar radiation. Since it can reflect radio waves, its existence is closely related to the transmission of short and medium wavelength radio waves. In the past, light waves emitted from the ground were used to study the ionosphere, so its condition from a height of 400 km or more could not be known. A meteorological satellite can broadcast radio waves from above to find out about the ionosphere condition from 400 km or more.
In the higher layer of the atmosphere, some charged particles come from the atmosphere, some due to the effect of cosmic rays, solar radiation, and solar microspheres entering the atmosphere. That was born. The Earth is like a large magnet. These charged particles are influenced by the Earth’s magnetic field, generating certain movements in the upper layers. Assuming we can find the magnetic field in the upper atmosphere, it is possible to deduce the motion law of overhead charged microscopic particles. This will explain some phenomena (such as aurorae) above. Artificial meteorological satellites provide us with the ability to explore that overhead magnetic field.
The change of clouds always manifests the weather change, so someone once said clouds are the face of weather. But in the past, one could only observe clouds from the ground; the field of view was not wide; Moreover, each time there are dense clouds, the clouds above will be obscured, people are very difficult to know clouds above. Artificial meteorological satellites fly in all clouds. It can probe and measure from above to the cloud state of a large area, transmitting images to the ground, thus overcoming the disadvantages of observing clouds from the ground. Combining both sources is beneficial for accurate weather forecasting. Since the satellite image map has been transmitted, any tornadoes arising on the sea surface cannot escape the satellite’s eye. Therefore it plays a huge role in cyclone prediction and accident prevention.
In the lower layer, the air temperature and humidity distribution are uneven. Its characteristic is to emit infrared radiation continuously. The meteorological satellite that receives these radiations can predict the vertical distribution of temperature and humidity in the low air layer.
Someone will say that people used meteorological missiles to probe the atmosphere at higher levels before the invention of the meteorological satellite. If there are meteorological missiles, what else do you need meteorological satellites?
Of course, a meteorological missile is also a kind of tool for detecting the upper atmosphere. But the scope of its discovery was limited. The time it spent in the atmosphere was relatively short, so the resulting material was scattered. If organized into a meteorological missile network to measure, although it can overcome some defects, it costs a lot of money and resources, and it is not easy. Meteorological satellites, compared to meteorological missiles, have many advantages. It operates in the atmosphere for a long time, more than an hour or so it rotates around the Earth, its flight path passes through different places on the Earth to fly through the sky of many regions.
There is also a type called a geostationary meteorological satellite; it flies in the equator’s sky, 36,000 km from the ground, speeds synchronous with the speed of rotation of the Earth. So for the Earth, as if it were only standing high above the equator, it could observe a certain region’s meteorological situation on the Earth. This for meteorological forecasting has very clear advantages. This type of meteorological satellite learns meteorological information in a wide range, has continuity, is very useful for studying meteorological change laws. Therefore, compared to the missile, it has superiority.