In recent days there has been a great deal of talk about a very strong El Niño and the extreme weather it could trigger.

But what exactly is El Niño, and how much could it really affect Greece? Analysis by Giorgos Tsatrafyllias for protothema.gr.

1. What is El Niño?

El Niño is a natural phenomenon that occurs every few years in the Pacific Ocean. A vast area of sea near the equator becomes warmer than usual, and this change then goes on to affect the atmosphere too.

2. Why does the sea warm up?

Normally, winds push warm water towards Australia and Indonesia. When those winds weaken, the warm water spreads eastwards instead. At the same time, less cold water rises up from the depths, so the central and eastern Pacific becomes warmer.

3. Why do the winds weaken?

This is part of the constant natural interplay between the ocean and the atmosphere. An initial shift in the winds can set the phenomenon off, and the warmer water then goes on to alter pressure systems and wind patterns, allowing El Niño to strengthen further.

4. How does it affect the atmosphere?

The warmer sea heats the air above it and adds more moisture, which changes where air rises, where clouds form and where rain and storms occur. In this way, atmospheric circulation is gradually altered.

5. How can something happening in the Pacific affect other countries?

The atmosphere works as one large, interconnected system. A significant change in one region can trigger changes much further afield, which is why El Niño can affect rainfall, temperatures and storms in various parts of the world.

6. What does “very strong El Niño” mean?

Quite simply, it means that the sea in a specific area of the Pacific has warmed considerably more than usual and the phenomenon is intense. It does not mean that extreme weather will occur everywhere in the world.

7. Does a very strong El Niño mean a very harsh winter?

No. The term “very strong” describes El Niño itself, in the Pacific. It does not describe the winter in Greece or in Europe; these are two entirely separate things.

8. Could it affect Greece?

Yes, it could, but only indirectly. There is no simple rule stating that El Niño automatically brings more cold, more rain or more snow to Greece. The country’s weather depends on many other factors as well.

9. Can we predict El Niño what kind of winter Greece will have?

No. It can offer certain indications, but it cannot predict the Greek winter on its own. It is just one of many factors that meteorologists take into account.

10. Why is there so much scaremongering?

Because the phrase “very strong El Niño” sounds alarming. However, it is wrong to interpret this as meaning that an extreme winter is coming to Greece.

El Niño is a significant phenomenon that can affect the weather in many parts of the world. On its own, however, it cannot tell us whether Greece will experience flooding, snow, severe cold or major storms.

In short: a very strong El Niño does not mean a very harsh winter for Greece. What is needed is information and monitoring, not scaremongering.