Lightining. Image by GreenSociety.

Lightining. Image by GreenSociety.

ZIMSEC O Level Geography Notes: Weather Hazards: Lightining

  • Is typically caused by the physical characteristics of cumulonimbus weather conditions.
  • As rain drops fall the energy which they have causes a positive charge to develop at the top of a cloud and negative charges to develop at its base.
  • The earth becomes negatively charged.
  • Lightning, which simply flashes of electricity, moves from the top of the cloud to the bottom of the cloud and from.
  • It also occurs from the bottom of the cloud to the ground.
  • Also as water droplets and ice crystals in clouds fall and collide with one another, especially in super-cooled water vapor, they form like charges from which flashes of electricity move from part/cloud to another part/cloud with a different charge.
  • Due to the last process outlined above most lightning flashes occur within and between clouds.
Image via Pixgood.

Image via Pixgood.


  • It is caused when a lightning flash suddenly heats and expands the surrounding air during discharge causing booming sound-waves.
  • Because the speed of sound is much less than that of light an observer who is at a distance sees the flash well before they hear the noise.

Dangers of Lightning

  • In Zimbabwe and other tropical countries a lot of people die from lightining strikes.
  • Usually lightning strikes the tallest conducting item as it seeks the quickest way to reach the ground.
  • In empty places where there are not trees or buildings standing human beings become likely targets.
  • Lightning also causes eletrical surges in power grids which might damage unproctected electrical gadgets if they are plugged in and switched off.
  • Can damage buildings especially in rural areas where there are relatively few build up places and buildings present the tallest conductors.

Mitigating the dangers of lighting.

  • Protect your home using a lightning conductor see below.
  • Wear rubber shoes when going out during thunderstorms.
  • Take shelter from lightning under a group of shorter trees, taking shelter under the a lone tree or the tallest tree(s) will make you a likely target.
  • Stay inside a car or bus.
  • Do not use electrical gadgets.
  • Do not take a bath or shower as some installations e.g. ZESA use electrical pipes to “earth” household electrical circuits.
  • Do not walk on higher grounds/hills/mounds/open spaces during a thunderstorm.
  • Do not walk through water puddles a nearby lightning strike might be conducted through the water.
  • Do not carry metal objects like pails on your head during thunderstorms.
  • Do not touch metal objects like fences during a thunderstorms.
  • Do not wash dishes in metal sinks during the storm or touch the kitchen faucet.
  • Do not carry sharp spiked metal objects like garden forks outside during a storm.
Lightning Conductor. Image via Elliot Electric.

Lightning Conductor. Image via Elliot Electric.

To access more topics go to the Geography Notes page.

Quick NetOne, Telecel, Africom, And Econet Airtime Recharge

If anything goes wrong, chat with us using the chat feature at the bottom right of this screen