What is the forecast of CCTV satellite cloud images?
Meteorological observation and forecasting are closely related to the national economy and people’s daily lives. The emergence of meteorological satellites has provided revolutionary technical means for meteorological observation. Meteorological satellites are equipped with various meteorological remote sensors, which can remotely sense the visible light, infrared and microwave radiation of the earth and the atmosphere. They can detect information such as temperature, humidity, air pressure and wind speed, and convert it into electrical signals and transmit them to the ground. The ground station restores the electrical signals sent by the satellite and draws them into various clouds, land surface and ocean surface pictures. After further processing and calculation, various meteorological data can be obtained. The meteorological cloud images of CCTV's weather forecast program are drawn based on the meteorological detection data sent back by meteorological satellites.
There are two types of satellite cloud images for CCTV’s weather forecast. One is the geosynchronous orbiting meteorological satellite cloud image, which has various cloud systems and longitude and latitude networks on the image; the other is the polar orbiting meteorological satellite cloud image, which has images There are oceans, clouds, plateaus, deserts, ice and snow, vegetation and rivers. Satellite cloud images are also divided into visible light cloud images, infrared cloud images, panoramic cloud images and regional cloud images. Cloud images received directly from satellites are only black and white images. For the convenience of research and to make it easy for the audience to understand, meteorological workers marked the cloud images with national borders and city marks, and color-processed the cloud images based on the principle of spectrum to make them close to human visual habits: green represents vegetation; ocher represents vegetation. Land; blue represents ocean, etc. Since large cloud systems reflect sunlight, the signals of various cloud systems received by meteorological satellites are gray-white. Therefore, the color of large rainfall cloud systems we see from satellite cloud images is gray-white, not rich black.
The work of producing satellite cloud images is quite complex. Each morning the weather forecaster on duty determines the type of cloud image to use in the weather forecast. Meteorological center personnel process the received images as needed, including cloud image positioning, splicing processing, projection transformation, geometric distortion correction, radiation distortion correction, drawing isobars and isotherms, etc. Image data from polar-orbiting meteorological satellites are usually received twice a day. Each time, meteorological data from three adjacent orbits (each orbit is about 3,000 kilometers wide in the lateral direction) are received. These data are projected and spliced to obtain a single image that can completely cover it. Weather cloud map of China. Next, color synthesis and partial enlargement are performed. In addition, cloud images from geostationary meteorological satellites are received every half hour, covering about a quarter of the earth's surface. Making these cloud pictures into cartoon form can vividly display the changes of each cloud system, and based on this, the trend of the weather system can be predicted.
In April 1960, the United States successfully launched its first meteorological satellite, Tyros 1, which proved the great value and superiority of using satellites for meteorological observations. Meteorological satellite observations have a vast area, long observation time, and rapid collection of observation data. Therefore, they can improve the quality of meteorological forecasts and are of greater significance to long-term weather forecasts. Meteorological data provided by meteorological satellites have been widely used in daily meteorological operations, meteorological science, atmospheric physics, oceanography and fisheries research. The development and application of meteorological satellites are extremely rapid. Meteorological satellites gradually expanded from low-Earth orbit to sun-synchronous orbit, and then further developed to synchronous orbit. Polar-orbiting and synchronous-orbiting meteorological satellites complement each other to achieve global meteorological observations. The current global meteorological satellite observation network has greatly improved the accuracy and timeliness of weather forecasts, and can predict disastrous weather in advance, making great contributions to social development.
In the early 1960s, China had conducted preliminary exploration into meteorological satellite technology and atmospheric remote sensing issues. Since the 1970s, China has begun to receive data from foreign meteorological satellites and has conducted a large amount of research on cloud image analysis, infrared and microwave remote sensing, and weather forecasting. In the 1980s, the American "Tyros-N" series of meteorological satellite single-station receiving and processing systems were introduced. On October 1, 1986, China broadcast satellite weather cloud images and weather forecasts on television for the first time. On September 7, 1988 and September 3, 1990, China successfully launched two "Fengyun-1" polar-orbiting meteorological satellites, marking that China's satellite meteorological work has entered a new stage. The main remote sensing equipment of "Fengyun-1" is two five-channel visible and infrared scanning radiometers, with a scanning width of 3,000 kilometers and a subsatellite point resolution of 1.1 kilometers. Each channel is used to capture daytime cloud images, day and night cloud images, water, ice, snow and vegetation images, ocean water color images, surface and sea surface temperatures and images. Other important equipment on the star include three image transmission systems and computers. The satellite is a hexahedron of 1.4×1.4×1.2 meters, weighs 900 kilograms, orbits at an altitude of 901 kilometers, and orbits the earth 14 times a day. The ground system consists of three ground data receiving stations in Beijing, Guangzhou and Urumqi and a data processing center located at the National Satellite Meteorological Center in Beijing. The data received in Guangzhou and Urumqi are transmitted to the center in real time through communication satellites, and the data in Beijing are transmitted to the center through microwaves. The center processes meteorological satellite data and produces satellite cloud images for use in meteorological research and forecasting. During the normal operation of these two satellites, China's weather forecasting work used its own high-quality satellite cloud images. In addition to using cloud images from the Fengyun-1 satellite, China usually receives and uses data from the U.S.'s NOAA polar-orbiting weather satellite and Japan's Sunflower synchronous-orbiting weather satellite.