It's going to be a scorching summer, some websites announced, passing it off as a reliable forecast. We asked meteorologist Paolo Corazzon whether record temperatures really are in store for us.
"What the hell is going on with global warming?", United States president Donald Trump asked in January when the Midwest was struck by an unprecedented cold snap, with wind chill temperatures in Chicago reaching -50 degrees Celsius. Now that summer is approaching, climate change is once again proving "useful" to those websites that, in the hope of racking up clicks, paint apocalyptic scenarios: "From as early as the end of May, the heat will be hellish." We wanted to shed some light on the matter by asking physicist and meteorologist Paolo Corazzon of 3Bmeteo.
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Is it true that the summer of 2019 will be scorching, as many news websites have reported in recent weeks?
Some meteorology websites, in order to gain visibility, drop "bombshells" in the hope that someone will take the bait: articles have been circulating these days forecasting a boiling summer, with 40 degrees in the north; you can read something like this every year. In March, however, it is impossible to give precise and reliable indications about the summer.
What can be said is that in recent years the trend, in the Mediterranean area and therefore on our peninsula, has been towards increasingly hot summers and, especially in the centre-north, increasingly dry ones.
Is the trend towards increasingly hot summers due to global warming?
Without a doubt. The Earth is warming up, and the Mediterranean is among the areas where the phenomenon is most evident, and therefore where the probability of having particularly hot summers is highest.
This winter, too, we witnessed the effects of climate change. In the south there were heavy snowfalls, but for the north it was a limp winter, with scarce rainfall, very little snow on the Alps, and above-average temperatures. In Italy it is precisely the northern regions that are suffering the consequences of global warming the most, frequently experiencing periods of drought. Right now our rivers are running dry: in March, that should not be happening.
Will the return of El Niño cause temperatures to rise in the coming months?
El Niño is a natural phenomenon corresponding to a temporary warming of the waters of the Pacific Ocean. It occurs in a fairly cyclical manner, every 4–5 years, and is then followed by La Niña, that is, a cooling of the waters.
It concerns the Pacific Ocean: Europe is only affected when El Niño or La Niña episodes are particularly strong. The event that does appear to be arriving in 2019, however, will not be a marked one, so its influence on the weather in the Old Continent will be minimal.
What will be the effects of the slowdown of the Gulf Stream?
As the temperature on the planet rises, glaciers are melting — including those in Greenland, which are made of fresh water and, as they flow into the sea, cause a change in ocean salinity with a consequent modification of ocean currents. The Gulf Stream could slow down and therefore no longer be able to reach Europe, which might consequently have, despite global warming, a somewhat cooler average climate in the future. In my view, however, this cooling caused by the Gulf Stream slowdown would be more limited than the warming that we humans are causing. And which is producing an intensification of the climate, with increasingly violent weather events, as the Earth seeks a new climatic equilibrium.
One curiosity: why does the city of Lecco warm up faster than the rest of Italy?
Because of climate change, atmospheric currents in Italy are moving from north to south with increasing frequency; the winds that cross the Alpine arc, as they descend onto the lakes of Piedmont and Lombardy, warm up: this is what is known as the Föhn effect. In recent years, the city of Lecco has frequently experienced days affected by this wind circulation, which has brought particularly mild temperatures.
