The increase in lightning is due to the rise in temperature. Lightning occurs more frequently when it’s warmer. According to the new study led by David M. Romps, the frequency of lightning strikes will increase 12% for every degree of rise in global temperature, therefore potentially resulting in a 50% increase in lightning strikes by 2100. Romps’ predictions were also determined by the increasing thickness of thunderclouds. Studies show that bigger clouds generate more lightning.
Lightning is created when a spark moves from a positively or negatively charged area of a cloud to an area with the opposite charge. Then, the upward movement of air, called vigorous updrafts, shakes particles in the cloud, which charges them. Small ice particles usually contain a positive charge and travel to the tops of clouds. Romps and his colleagues created a computer program that can determine how much lightning is generated through precipitation and how much activity a thunderstorm produces. In 2011, their program predicted 77% of all lightning flashes for the entire year.
As the earth continues to warm from climate change, the conditions for thunderstorms to get triggered happens on a more regular basis, and these storms will be more energetic. It’s not only the danger of being struck that increases. Lightning is responsible for half of US wildfires, and with the atmosphere becoming warmer, that means that there is only a greater risk of wildfires.
Tim McDonnell reporting for Mother Jones says, “In one 24-hour period in August, lightning in Northern California started 34 wildfires. The study doesn’t make any specific predictions about wildfire activity, but knowing about future lightning conditions is an important part of that equation.”
Increased lightning will also impact greenhouse conditions, which could end up being both a good and a bad result. It could potentially produce more ozone, which is a dangerous ozone gas, but on the other hand, lightning could create more nitrogen oxide compounds, which help reduce levels of methane, another strong greenhouse gas. Whatever the outcome, look for a more stormy world unless action is taken to address climate change.
(Photo courtesy of Simon Bradley)