1 Introduction Simple rainfall monitoring can no longer meet the research in the fields of meteorology and other scientific research. The research on the structure and type of rainfall has become the focus of researchers. The raindrop spectrum is one of the important tools for in-depth understanding of the internal structure and evolution of rainfall. The parameterization of the numerical model microphysical process provides a reliable basis. Using raindrop spectrum data and cloud structural characteristics to accurately determine the type of rainfall, the ZR relationship or MP distribution derived from the raindrop spectrum can retrieve the local radar wave strength, which is very good for precipitation estimation, monitoring and early warning of severe weather, etc. Guiding significance. Rainfall, as an important disturbance factor, has an important impact on the accurate estimation of soil respiration. The impact of rainfall events, rainfall and the response pattern and pattern of rainfall patterns on the "Birch effect" (a phenomenon in which rainfall strongly stimulates soil respiration) is particularly noticeable. . The impact of rainfall intensity on the soil water content at different depths in bare land and land with high vegetation coverage is also the focus of research on soil and water conservation. The traditional precipitation characteristic research mostly adopts the test paper method, the observation and reading data are all controlled manually, the workload is large, and the accuracy is low. The emergence of the raindrop spectrometer has changed the previous method of manually obtaining data, which can be measured unattended in all directions, but the general laser raindrop spectrometer can only get the initial raindrop spectrum data, and its software cannot perform further meteorological factor analysis. Gradually unable to meet research applications. 2 Observation system design 2.1 Objective A laser emitting source (laser diode and optics) is used to generate a set of parallel beams (infrared, non-visible light). A lens photodiode at the receiving end measures the light intensity and converts it into an electrical signal. When the raindrop passes through the laser beam, a receiving signal is generated, and the diameter of the raindrop is calculated by the reduced amplitude. In addition, the falling speed of the raindrop is measured by reducing the duration of the signal. Accurately determine the minimum diameter of the object to reach 0.16mm. The AZ-MR101 cloud and precipitation characteristic observation system can measure the total amount, size, intensity, and speed of falling raindrops. The software uses a Chinese interface, which can display the raindrop spectrum at any time, and can also calculate the characteristic diameter of the raindrop spectrum to provide basic data for studying the MP distribution and ZR relationship. Integrate sensors of other meteorological units to analyze the climate change characteristics of local or large areas; combined with other soil parameters such as soil respiration and water content, it can analyze the physical and chemical characteristics of the soil at the study site or area to estimate carbon emissions or evaluate soil and water conservation . 2.2 Observation point selection The selection of observation points should consider the regional environmental characteristics, such as terrain, meteorology, industrial and agricultural distribution, etc., which can represent the local typical environment. The sampling point should avoid the local pollution sources that discharge acid and alkali substances and dust as much as possible, and the main street traffic pollution sources. There should be no tall trees or buildings covering the rain and snow around. For soil and water conservation monitoring, select representative sample points in the monitoring area, and try not to obstruct the surrounding area. 2.3 Observation indicators Rainfall, rainfall speed, rainfall particle size, rainfall intensity, rainfall grade, raindrop spectrum, ZR relationship diagram. Average diameter Dm, mode diameter Dd, average volume diameter Dv, dominant diameter Dp, median diameter Dnd, median volume diameter Dn, 2.4 Composition of observation system The AZ-MR101 cloud fog precipitation characteristic observation system is composed of raindrop spectrometer and raindrop spectrum analysis software DA100. Optional sensors with heating function to adapt to extremely harsh environments. Can simultaneously connect wind speed sensor, wind direction sensor, temperature and humidity sensor Anti-electromagnetic bracket to ensure measurement accuracy, digital signal, long-distance transmission. Support server and client working mode, easy to remotely manage data, support network data reading, table and graphical real-time display. Chinese software interface, display raindrop spectrum at any time, automatically calculate various characteristic diameters of raindrop spectrum 3 data processing After the experiment is completed, DA100 software will give the data chart and final result as shown in the figure below. Including collection date; collection time; average rainfall intensity every 5 minutes; total rainfall intensity per minute; liquid rainfall intensity per minute; solid rainfall intensity per minute; total rainfall; radar resolution per minute; total number of raindrops, etc. Directly use the software to display 22 kinds of raindrop size ranges and 20 kinds of rain speed ranges; Chinese software interface displays raindrop spectrum at any time; automatically calculate the average diameter Dm, mode diameter Dd, average volume diameter Dv, dominant diameter Dp, median diameter Dnd, median volume diameter Dn. Through the raindrop spectrum data software, the secondary product inversion function and export function can be directly performed, and the ZR relationship (radar reflectivity and rainfall intensity) and MP distribution can be directly fitted. The software can simultaneously control and monitor the operation of multiple instruments in multiple locations, and the rainfall intensity and raindrop spectrum can be directly exported. 4. Application examples Relevant researchers at Beijing Forestry University used the LNM laser raindrop spectrometer to continuously observe the precipitation process from August 2006 to January 2007 in the mountainous area around the Miyun Reservoir in Beijing; combined with the methods and results of previous research on raindrops, they generated from rainfall Starting with the mechanism of energy, observation and analysis of changes in raindrop characteristics and kinetic energy of rainfall inside and outside the plantation forest around the Miyun Reservoir in Beijing. The results show that the average diameter of the natural raindrops outside the forest and the median diameter of the raindrops have a tendency to increase with the increase of rainfall intensity; the diameter of the raindrops outside the forest is smaller than that in the forest, and the relationship between the diameter of the raindrops outside the forest and the cumulative rainfall The forest is smooth; under light rain (≥0.35mm / h) meteorological conditions, the kinetic energy of rainfall in the forest is significantly higher than that of the outside forest. It can be preliminarily believed that the forest canopy has an increased effect on rainfall energy when the intensity of the rain is small. 5. References (1) Luo De, Yu Xinxiao, Dong Lei. A preliminary study on rainfall characteristics inside and outside Pinus tabulaeformis plantations in Miyun Mountain area [J] Bulletin of Soil and Water Conservation, 2008: 28 (2), 67-70 (2) Rhodes. Study on the dynamic characteristics of rainfall under the influence of forest vegetation in Beijing mountainous areas [M] Beijing Forestry University, 2008, 6 Chongqing Sungrace International Trading Co.,Ltd , https://www.sungracetrading.com
AZ-MR101 Cloud and Fog Precipitation Character Observation System