GB 31221-2014Specifications for observing environs protection of surface meteorological station (English PDF)

3.1.1 General requirements

3.1.1.1 duration of protection 3.1.1.1.1 national reference climatological station site should be at least 50 years of stable. 3.1.1.1.2 national basic weather stations and national general weather station site should be kept for at least 30 years of stable.

3.1.1.2 surroundings 3.1.1.2.1 observation site four weeks should open flat, smooth airflow and maintaining natural daylight. 5000m, wind up the other direction in the observation field range of 90 ° 3.1.1.2.2 upwind 2000m, shown in Figure 1, in this range should not be regulated Zoned industrial and mining areas, the construction should not be easy to produce smoke and other air pollution facilities; the wind direction in the observation field national reference climatological stations in the 5000m range Also not planning a total population of more than 5,000 neighborhood. 3.1.1.2.3 embodiment should not be blasting, drilling, quarrying digging of sand, earth and the like in the observation field range of 1000m compromise safety ground observation field of meteorological activity. Description.

--- R & lt most upwind wind field observation range 90 ° edge of the outer fan radius;

--- R & lt remaining outer edges of the fan radius direction of the observation field.

Note. The schematic westerly example, limit the scope of the actual local wind up prevail.

1 a schematic view of Zhou Bian field of meteorological observation restricted planning zone

3.1.2 Restrictions on obstacles

3.1.2.1 obstacle-controlled areas demarcated In the field of meteorological observation obstacle four weeks should be designated control area, the control area should range in accordance with Table 1. Table 1 meteorological observation field four weeks obstacle to the control area in meters From outside the National Collections meteorological observation stations outfield fence outwardly extending around National reference climatological stations 2000 National basic weather station 1000 National general weather station 800

3.1.2.2 restricting national reference climatological stations and the national basic weather station controlled area obstacle requirements 3.1.2.2.1 height distance to the obstacle at any point in the control area is less than 1/10. Obstacles and observation field fence 3.1.2.2.2 controlled areas closest distance of not less than 50m. National restrictions

3.1.2.3 General requirements obstacle weather station controlled area 3.1.2.3.1 height from the obstacle at any point in the control area is less than 1/8. 3.1.2.3.2 controlled area and observation field fence nearest obstacle distance not less than 30m. There are additional restrictions

3.1.2.4 sunlight or solar radiation observed meteorological stations surrounding obstacles requires 3.1.2.4.1 national reference climatological stations and national weather substantially in the directions of sunrise and sunset direction (this range is not limiting control area), the barrier Blocking the shutter is not greater than the elevation angle 5 °. 3.1.2.4.2 weather countries generally in the directions of sunrise and sunset direction (this range is not limiting control area), the elevation angle is not blocked by obstacles At 7 °.

3.1.3 restrictions on sources of influence The minimum distance between the source and observation affect the outfield fence shall meet the requirements in Table 2. The minimum distance between the unit and Table

2 Effects of source of meteorological observation outfield fence m Impact source category national reference climatological stations the state's basic national weather stations in general Railway embankment > 200 > 200 > 100 Roadbed > 50 > 50 >

30 Artificial construction Water > 100 > 100 >

50 Garbage dumps, sewage outfall and other sources influence > 500 > 500 > 200

3.2 regional weather station

3.2.1 general requirements

3.2.1.1 observing Zhou Bian environment to maintain an open field, to ensure that the sensing surface ventilation equipment and non-shade. 10m range within Zhou Bian

3.2.1.2 observed field should not be an obstacle.

3.2.2 Elements observational requirements

3.2.2.1 Temperature 3.2.2.1.1 Effect horizontal distance between the source and the temperature sensor should be greater than 10m (traffic not so limited weather stations). 3.2.2.1.2 manmade water level and temperature sensor distance should be greater than 10m. 3.2.2.1.3 When the sun elevation angle greater than 20 °, around the obstruction not cast a shadow on the temperature sensor.

3.2.2.2 Precipitation Horizontal distance between the obstacle and the sensor should be greater than the height difference between the sensor and the obstacle.

3.2.2.3 Wind Wind rod obstacle horizontal distance should be greater than the obstacle (from higher wind starting bar is mounted above the basal plane) three times their height.

3.3 Other meteorological observation station Meteorological observation stations outside meteorological observation stations national and regional meteorological stations, functions as a national meteorological View Referring stations

3.1 technical requirements, technical requirements of the function corresponding to reference regional meteorological stations 3.2. Measurement Method 4

4.1 observation field Zhou Bian the control zone Vertical edges of the observation point on a straight line extending outwardly field (see region A 2), at the apex of a sector extending 90 ° (see the region B

2 Domain), an approximately circular region formed by combining the control area for the observed field, extending outwardly from the subject in Table 1. Circular, hexagonal, etc. Shaped its inscribed rectangular observation field range of the control region designated in accordance with the present method. FIG 2 observed field Zhou Bian the control area delineated schematic

4.2 observed field to the obstacle distance A fence along the observation field, select the nearest distance to the obstacle point, the instrument used to measure the distance to the obstacle or the measuring tape (accurate to 0.1m).

4.3 and obscured obstacle height elevation than the distance

4.3.1 height than distance

4.3.1.1 Figure 3, using direct measurement of the instrument height H of the obstacle to the point fence and vertical horizontal distance D (accurate to 0.1M), linear Then calculate the distance obstacle height ratio. Description. H

--- obstacle distance observation plane height above the site; D

--- distance to the obstacle and the nearest point level measurement point fence vertical distance; elevation angle [theta]

--- occlusion. Figure 3 a schematic view of the obstacle than a height distance and elevation angle measurement occlusion