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Anastasia Balezdrova

Unlike previous years, this year summer was late in many regions of Europe and when it finally came, it brought heavy rains, successive floods and heavy hail, such as that which occurred in northwestern Bulgaria two days ago.

The natural phenomena were so intense that they caused more than 10 casualties and reasonably raised the question about their cause. GRReporter sought a response from Konstantinos Lagouvardos, meteorologist and researcher at the Greek National Observatory.

Mr. Lagouvardos, can modern science protect people from natural disasters and how? Is it possible for meteorology to detect in advance phenomena such as the strong hailstorm in Bulgaria a few days ago and warn people in time?

Yes, we can warn of severe weather phenomena and we do so. The phenomenon mentioned was caused by a very severe storm, followed by very large hailstones.

All meteorological services and research centres forecast severe weather phenomena, which include storms as well. Nevertheless, it is difficult to predict whether a storm will bring hail. And even if the probability of hail is forecasted it is extremely difficult to determine its size. This is really hard.

I would also like to note that storms are local phenomena. This means that in one place the phenomena could be extremely intense, for example, very heavy rain and large hailstones, and much weaker in other adjacent places. Therefore, we can predict that in a particular region, for example in central Bulgaria, northern Greece, etc. we expect the weather to become worse and bring heavy rain and possibly hail, but it is very difficult to inform, hours earlier, where the phenomena will be most intense.

In the second stage, after the beginning of the phenomena, we follow them with radars, systems for lightning and satellite images that show us the exact place where the severe phenomena are taking place at that moment and help us to predict the direction to which they will move within one hour for instance.

Are there ways to counteract these phenomena? For example, years ago Bulgaria used missiles to break up the clouds that bring hail.

Yes, this practice exists in different countries. Here in Greece, we use another method, we use small planes that fly through the storm clouds while they are in the initial stages of their formation and sprinkle silver iodide. The aim is to reduce the size of the hailstones in order to minimize the risk of loss of lives and extensive damage.

We can say that this measure is effective to some extent, but only within a limited area. It must be applied at the right place at the right time. However, as we do not have available an infinite number of missiles or aircraft, the area is limited. In that specific area the measure can actually produce results and reduce the size of hailstones or contribute towards avoiding the hailstorm. However, it is not possible to apply it on a larger scale.

Since the beginning of summer, there have been many different severe weather phenomena in Bulgaria, including severe floods and that hail, which caused casualties. Do you think they can be taken as indicative of the occurring global climate change?

No, I do not think so. My opinion is that some years we have really adverse weather conditions. I would like to point out that very strong storms arise in the countries of the North and Central Balkans during the summer months. In many of these regions, summer rains are almost as frequent as winter ones. I would say that summer storms and all that they may include, such as lightning, hail, heavy rain, etc., are a feature of the weather in the region that includes northern Greece too.

In some years, these phenomena are more intense than they are in others, when they are milder. I do not think this is a result of the climate change but rather of the natural weather variability.

What is the mechanism for the protection of citizens in Greece? How do you cooperate with the civil protection service and other institutions? Is there some form of training on how citizens can protect themselves from adverse weather conditions?

The competent institutions report on the occurrence of severe weather phenomena and Civil Protection makes the appropriate announcement to inform the public of the relevant self-protection measures they should take. Unfortunately, there is no training for citizens.

As during summer storms the majority of people are outdoors the probability of problems due to lightning, hail, heavy rain, etc. is high. I would not say that citizens know how to react in such a situation.

What are your tips on how we can protect ourselves from such phenomena?

When we plan to go the mountains, we have to check the weather conditions the day before. This information is easy to access as there are dozens of websites that contain it.

In the event that the weather forecast for the particular region we are going to visit is for severe phenomena then we have to consider what measures to take. The best advice is to postpone the outing, but if we eventually decide to go, we have to secure a shelter if something happens. In such situations, the only way to protect ourselves is to go to a closed room, because if we are outdoors during a storm the risk of being struck by lightning is quite high.

It is easier to find shelter if we are in the city. Anyway, summer storms are brief and we just have to protect ourselves during their peaks.