Lightning Damage

In Awe of Mother Nature – The Explosive Power of Lightning

One thing is for certain, climate change has had a profound effect on 2024 spring weather events. Dubuque had the warmest February on record this year. Spring arrived 20 days earlier than normal, and a devastating tornado ripped through Greenfield Iowa, producing 175-185 mile per hour winds, leaving a path of utter destruction. Disastrous flooding is occurring in parts of the state. We have witnessed severe weather in several forms.

Lightning Damage

We often see trees that have been struck by lightning, with bark splitting, bark loss and some wood splintering. Some lightning strikes are massive, quite literally blowing a tree apart! I have only witnessed massive strikes a handful of times. The accompanying photos are of a massive lightning strike to a White pine tree this past May. The tree was perhaps 100 foot tall. Besides scattering splintered branches and limbs in all directions, it caused the trunk to blow apart and separate about 10 feet above the ground. The top section, or what was left of it, came straight down penetrating the ground several feet deep. This was by far the worst case I have ever seen.

Lightning strikes can be frightening especially when they are followed by a loud crack of thunder. Photographs of spectacular lightning displays can be awesome. Lightning has caused house fires, killed cattle, and more often than we realize, killed humans. My biggest fear today is that lightning will strike close by and damage our home electronics.

A Little About Lightning

Cloud to cloud lightning and cloud to ground lightning are two basic forms that we are familiar with. It is the cloud to ground lightning that causes problems. There are many variables that determine the makeup of a lightning strike. Lightning forms as the result of storm clouds passing over other clouds or passing over land, creating charged fields. In cloud to ground lightning, a negative charge or field builds at the base of the clouds while a positive charge builds on the surface of the ground and extending up tall structures, including trees. Because opposites attract, the positive and negative charges come together to create a lightning strike. It has been estimated that lightning can be hotter than the surface of the sun.

Tree damage is a product of the strength and duration of the lightning charge or strike and can vary greatly from time to time and tree to tree. A single tree can be struck by several streamers from a single strike.

Most damage is caused by the acoustic or explosive shock wave radiating from the lightnings path. Additional damage is done by steam explosions from rapidly heated water turning into vapor in areas beneath the bark including the cambium and sap conductive tissues. The shock wave generated by the lightning core has about 10 times the energy released than the tissue heating and steam expansion.

I still enjoy a good thunderstorm!