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I do not need to tell you that this summer is exceptionally warm in Europe. In an attempt to explain this, experts point to the current El Niño in the Pacific, which is exceptionally strong this year. But how can something on the other side of the world affect the weather over here? That is a suitable topic for this column.
You may know that all around the Earth, at the equator, there is a strong easterly wind that blows year-round, called the trade wind. This perpetual wind acts as a conveyor belt for tropical storms. Hurricanes form over the Atlantic, while typhoons form over the Pacific. This way, the trade wind extracts much solar energy from the oceans, causing the water temperature to remain stable over the long term. However, once every few years, the trade winds are stronger or weaker than normal for reasons that are very complex. As a result, the oceans are either cooled more, or less, than usual.
Take a globe and observe that the Pacific covers roughly half a hemisphere, and also consider that this ocean contains half of all the water in the world’s seas. That is why excess warming is particularly felt over there when the trade winds die down. This significantly alters the weather around the Pacific, and the phenomenon is called El Niño, the Christmas Child, because it becomes noticeable around Christmas time during the southern hemisphere’s summer.
The trade winds can also strengthen for a while. Then the Pacific actually cools more than usual, which also significantly disrupts the climate. This is called, you guessed it, La Niña. Both El Niño and La Niña neutralize the effect of the periodic variations in the trade winds, and in this way, the climate remains in balance over the long term. That’s a good thing, of course.
The effect on the weather is so significant because more than two-thirds of our planet’s surface is covered by water, which absorbs a staggering amount of solar energy that is then released into the atmosphere. Cooling one liter of water by one degree heats no less than over three cubic meters of air by one degree. Try mentally scaling these numbers to the Pacific, and you will realize once again that we are nothing but dust in the wind.
It turns out that the current warming of the surface water in the Pacific is twice that during a typical El Niño. We are experiencing, so to speak, two of them at once. The westerly winds over there are much warmer and more humid than expected, and you can imagine that we are in for meteorological spectacle this year. We are even feeling the indirect effects here in Europe, and the only thing we can do about it right now is shelter and wait for it to blow over.
