Super "laser pointer" to explore the atmospheric changes

China weather news: global warming, less sea ice, more extreme weather, more air pollution... Climate change, environmental change and human activities on the climate, environment and ecology, the negative effect is becoming the major problems affecting the sustainable development of human society, actively respond to climate change has become a global consensus.

So what exactly has changed?

To ascertain the atmosphere the mystery of the infinite change, in 2012, the first batch of national natural science foundation funding national major scientific research instruments and equipment to develop special - multiband atmospheric composition more main integrated passive detection system (hereinafter referred to as APSOS) officially launched.

Recently, the system was demonstrated at the huainan atmospheric science research institute in anhui province. At night, a beam of green, yellow lasers shot into the sky, as if a super best laser pointer had been used to explore the spatial and temporal changes of greenhouse gases and pollutants in the atmosphere. After the completion of commissioning, the system will be transported to the international cosmic ray observatory in Tibet, 4,300 meters above sea level, for the long-term study of atmospheric observation of the Tibetan plateau.

Study the neutral atmosphere

Climate change can be revealed

In the past, advances in atmospheric sciences respectively based on the basic laws of physics and mathematics method, technology mainly by means of computer and the numerical method of numerical simulation and numerical prediction, to a large extent depend on the structure of the atmosphere, composition, process and change the global long-term monitoring, including direct detection and representatives of the automatic meteorological station network represented by radar and satellite remote sensing detection.

Earth system science, however, in addition to relying on existing satellite observations and ground base station network, there is an important aspect of urgent need, which can realize in the vertical direction, in view of the main elements of the neutral atmosphere, to obtain more comprehensive high vertical resolution and continuous observation data of high temporal resolution.

Atmosphere can be divided by height troposphere (about 10 km to 20 km) away from earth, the stratosphere (about 20 km and 50 km away from earth), middle (about 50 km to 85 km) away from earth, thermal layer (about 100 km to 800 km) from to escape and layer, hot layer below not charged atmosphere is called the neutral atmosphere. "It is possible to have a clearer understanding and understanding of the atmospheric mechanism on which climate and environmental changes depend on the multi-element continuous observation of the neutral atmosphere." The chief scientist of the APSOS project, lu dalen, a member of the Chinese academy of sciences, said.

APSOS is responsible

A neutral atmosphere will be opened

APSOS is around neutral atmosphere to detect, it led by institute of atmospheric physics, Chinese academy of sciences, joint domestic other six scientific research units to develop, also is the world's first set of the neutral atmosphere components and elements of large foundation integrated detection system.

Which researcher Pan Weilin said, the scope of the neutral atmosphere, APSOS by emitting laser, hit 30 pulses per second, just like handfuls of "sword" atmosphere "cutting", according to every few meters this precise atmospheric aerosol information, including PM2.5 in recent years, people care about most.

APSOS and utilization of the world leading level of the laser, microwave and terahertz remote sensing detection technology, not only can get the atmospheric temperature, humidity, wind and cloud distribution, and other meteorological elements, but also can real-time monitoring the changes of time and space of greenhouse gases and gas pollution, in order to realize the atmospheric vertical structure, movement and composition transportation research.

"APSOS system is completed, will not only boost in atmospheric environment detection in our country comprehensive national strength and technology level, can also for atmospheric environment monitoring and meteorological disaster forecast and space security provide valuable observations, helps to find the phenomenon that the new process, new atmosphere and understand." "Said luda.

The main passive remote sensing is combined

High precision measurement of atmospheric elements

APSOS includes five lidar, one millimeter wave measuring cloud radar, one terahertz superconducting radiation spectrometer and one combination telescope. From the aerial view, the composite telescope is located in the center of the building, equipped with the container of the container and its connection, the whole system is the "rice" type.

Will be more than one observation equipment placed in the same station, same area in the direction of zenith atmosphere for synchronous observation, for the atmosphere of many elements within the same vertical column characteristics at the same time, through the analysis of observational data processing, can learn that the regional distribution characteristics of the atmosphere. "Capture some transient processes with high spatial and temporal resolution to understand and understand the movement of the atmosphere," said pan. To understand the response of the whole atmosphere to solar activity and surface human activity in the long term.

Among them, the laser radar as active optical remote sensing detection equipment, through the atmosphere laser, laser beam interacts with the atmosphere of different material, the back scattering light signal from 4 piece of 1.2 meters in diameter mirror patchwork optical telescopes, be photodetector is converted into electrical signals, and has the advantages of high spatial and temporal resolution and high detection precision. The passive remote sensing device is a superconducting radiation spectrometer which can be used to detect the contents of greenhouse gases such as water vapor and ozone in the middle layer. With a strong atmospheric penetration capability, it can detect more distant targets.

"APSOS system, passive remote sensing is used to the way of combining range from from ultraviolet to infrared, and terahertz to multi-band detection technology of millimeter wave, the overall idea for the first time in the world, the system of the core technology unit adopts the international cutting-edge technology, realize the measurement of atmospheric elements and atmospheric composition a lot." "Said pan.