Lightning activity in the European Eastern Alps doubled in 40 years. What does this indicate?

Subject :Geography

Section: Physical geography ( Climatology)

Context:

Lightning activity in the higher European Eastern Alps doubled in the 2010s compared to the 1980s, according to a new study.

Details of the study:

Warming in the European Eastern Alps and surrounding regions is more pronounced than in the rest of Europe. Some scientific models have predicted that climate change can be a factor behind the increase in lightning activity, making it a good indicator of the climate crisis.
During the day, the peak is up to 50 per cent stronger, with more lightning in the afternoon and evening. Similar signals along the southern and northern edges of the Alps are present but weaker. The flat areas around the Alps show no significant trend.
The rising temperatures due to climate change are causing the frequency of thunderstorms and thus lightning to increase even further.
Thunderstorms always come with lightning and, like extreme weather events, have been made more frequent and intense across the world by climate change.
The topography of mountainous areas already makes them more prone to thunderstorms. Moreover, the melting of ice that covers these terrains has exposed larger areas to heating.
Harmful effects of Cloud-to-ground lightning:
- Cause power outages by damaging electricity supply infrastructure.
- Can spark fires at the sites they strike.
- People may get injured and even be fatally struck by lightning.
- Lightning also injects air pollutants like NOx and ozone into the atmosphere and threatens permafrost.

What is lightning?

Lightning is an electrical discharge that occurs when there is an imbalance between the storm clouds and the earth or even within the clouds.
Clouds are where lightning typically occurs.

Types of lightning

Intercloud or intra-cloud (IC): Harmless
Cloud to Ground (CG) lightning: Harmful as the ‘high electric voltage and electric current’ can lead to electrocution.

What causes lightning?

The rising temperature causes water vapour to condense as it rises in the cloud. The water droplets become minute ice crystals as their temperature falls below zero degrees Celsius.
They keep expanding until they are so heavy that they start to tumble to the ground. This results in a system where smaller ice crystals are travelling up and larger crystals are coming down simultaneously.
After a collision, electrons are released and triggered in a manner akin to the creation of electric sparks. A chain reaction happens as more collisions and electrons are produced as a result of the free electrons’ movement.
The upper layer of the cloud becomes positively charged as a result of this process, whilst the middle layer becomes negatively charged. Between one billion and ten billion volts separate the two layers’ electric potentials, which is a very significant difference.
A massive current, between 100,000 and one million amperes, starts to flow between the layers in a matter of seconds.
Earth is electrically neutral and a good conductor of electricity. It becomes positively charged in contrast to the cloud’s centre layer, though. Because of this, 15% to 20% of the current is also directed toward the Earth.