Risks of lightning

When the probability of an event occurring is very low or almost zero, in Korea we often say, “It’s lower than the odds of being struck by lightning.” Your odds of being hit by lightning, of course, are fairly low in your life, but you should not let your guard down because a lightning strike could lead to deadly consequences. Every summer we often hear of accidents caused by lightning.

On Aug. 25 last year, a crew member on board a boat was struck by lightning in the sea off the city of Tongyeong, South Gyeongsang Province, and taken to a hospital. On July 29, 2007, bolts of lightning struck Yonghyeolbong, a peak on Mount Bukhan, as well as Mount Seorak, killing five climbers and injuring six.

As lightning strikes are not as common as other types of accidents, the risks of lightning striking are often underestimated. However, once a lightning-related accident occurs, it can be fatal, so lightning is essential weather information you should check, especially in summer, when people tend to do more outdoor activities such as golfing, hiking and camping.

What causes lightning, and how is it observed? Lightning is an electrical discharge caused when imbalances between positive and negative charges in the atmosphere are created and settled. Lightning occurs within a cloud, between clouds, between a cloud and the air, or between a cloud and the ground. The Korea Meteorological Administration (KMA) provides realtime information on cloud-to-ground lightning strikes.

The KMA runs an automated lightning detection system with 21 sensors installed nationwide. The lightning detection system pinpoints the location of lightning by calculating the time difference between electromagnetic pulses from lightning to reach each sensor. The KMA’s system has a 95-percent detection rate for lightning on the Korean peninsula and its surrounding waters.

The lightning-related data collected from the system is updated for the public every five minutes on the KMA’s weather service website (http:// weather.go.kr). KMA also publishes an annual report on lightning in Korea and uploads it to its administrative website (http://kma.go.kr) to allow anyone easily to access lightning-related information.

According to the 2021 Annual Lightning Report released this year, about 124,000 lightning strikes were detected in Korea in 2021 alone. This number is 8 percent higher than the recent 10-year average of 116,000 strikes and 51 percent higher than the 2020 average of 83,000 strikes.

Approximately 72 percent of the annual lightning events in Korea occur during the summer months, from June to August, and August had the most lightning with 45,596 strikes, 37 percent of the annual total. In June 2021, lightning was detected at less than the 10-year average, and May and August had higher lightning counts than the 10-year average. If we look at the annual lightning count per unit area by metropolitan city and province, South Gyeongsang Province had the most lightning per year, followed by Daegu and North Jeolla Province.

Out of 240 countries in the world, the top five countries by total lightning count in 2021 were Brazil, the United States, the Democratic Republic of Congo, Australia and China. When factoring in the territory size, the top five countries were Singapore, Macao, Brunei, the Democratic Republic of Congo and Cambodia. In terms of total lighting count in 2021, Korea ranked 88th, and 86th in terms of the annual lightning count per unit area, which are figures slightly higher than the median rankings.

To prevent lightning-related accidents, the KMA provides users with a location-based lightning notification service on its mobile app. The KMA Weather App sends notifications to users in areas where lightning is expected to occur within an hour so that users can effectively use the app for safe outdoor activities. In summer, as you are more likely to be outside, you are more likely to be exposed to lightning risks.

Thus, before going hiking, camping or doing other outdoor activities, make sure to check weather forecasts and remember safety tips for lightning strikes. Moreover, it is also important to check lightning information on weather-related apps during outdoor activities to stay away from risky areas or objects in advance. I hope this summer does not see any lightning casualties.