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4、预防雷击火苏联引起森林火灾的火源中雷击火约占1.57％,在个别的年份发生雷击火的比例还要高。的究认为,随着静电电荷源(石油管道、电力线、船舶、飞机……等)的大量增加,雷击火的发生有着增长的趋势。所产生的电荷多次陂气流、蒸发、降水等从地面转移到空中和从空中又到地面,在这过程中,电荷的大部份被消散而形不成强的放电,但部份的电荷集中到平均离地高度2—4公里,等温线为0—10℃的积云中,它们成为引起森林雷击火的主要来源。雷暴云大约能存在1小时左右,在这时间内能发生300—400次放电现象。有40％的放电是从云向地的方向活动,而40％是从地向云活动,雷暴云在风或山谷环流的作用下移动速度经常能达60公里/小时,在它经过的地方与地表物相接触形成放电点,认为放电点一般是导电性强的地形地物,如地下水,粘土矿床暴露区、断层、较高的传导物体、以及具有放射性物质的地方。
4, the prevention of lightning fire The Soviet Union caused a forest fire ignition source of fire and lightning accounted for about 1.57%, in some years the proportion of lightning fire still higher. According to the research, with the substantial increase of electrostatic charge sources (oil pipelines, power lines, ships, aircraft ...), the occurrence of lightning fires tends to increase. The resulting charge multiple 陂 airflow, evaporation, precipitation, etc. from the ground to the air and from the air to the ground, in the process, most of the charge is dissipated and not form a strong discharge, but part of the charge concentration To cumulus clouds with an average ground-level of 2-4 km above sea level and an isotherm of 0-10 ° C, they have become the main sources of forest fires that cause lightning strikes. Thunderstorm cloud can exist about 1 hour, during this time can occur 300-400 times the discharge. 40% of the discharges move from the cloud to the ground, and 40% move from the ground to the cloud. The thunderstorm often moves at speeds of up to 60 km / h under the influence of wind or valley circulation, The contact of the earth’s surface with the formation of discharge points suggests that the discharge points are generally highly conductive topographic features such as groundwater, exposed areas of clay deposits, faults, higher conductive objects, and where radioactive material is present.