Jorge Morales
Santa Cruz de Tenerife (EFE).- One of Spain’s leading experts on tropical cyclones, Doctor of Physics and Senior State Meteorologist in Aemet Juan Jesús González Alemán, argues that “scientific evidence” suggests that these could be “more frequent” and even have “greater approaches” to the Canary Islands, although at the moment, he admits, “there is nothing clear” about this.
González Alemán, who was chosen to form a working group of the World Meteorological Organization to study this type of phenomenon and its relation to climate change, participates in the debate that has begun on the question of whether ‘Hermine’ was a isolated case or if it is usual, and if it is the result of climate change.
One of his colleagues, the delegate to the Canary Islands of the National Meteorological Agency (Aemet), David Suárez, and Professor Luis Cana, of the Institute of Oceanography and Global Change of the University of Las Palmas de Gran Canaria , recently published an informative article in ‘The Conversation’ on Tropical Storm ‘Hermine’.
And they conclude that it will be increasingly difficult for tropical cyclones to form around the archipelago due to the tendency to increase wind shear, a “key factor”.
The questions asked by “Hermine”
Juan Jesús González points out to Efe that “although it is a hypothesis to be taken into account, five or six years can pass, or even more”, without there being clearer answers to the questions that arose after ‘Hermine ‘.
But in this time interval, he does not exclude that “another phenomenon” similar “may continue to affect us”.
“It’s a subject that is very open to further investigation, but the indications, the evidence suggests that in the future they could be more frequent, they could have more facilities to reach the Canary Islands and also the areas coasts of the Atlantic Peninsula in good conditions,” he adds.
González points out that there are no studies focused on the Canary Islands, but conclusions can be drawn from the models used for the North Atlantic basin.
Some of these studies indicate greater tropical wave activity in the future, with a stronger African monsoon, which would imply a transfer of tropical cyclones a little further north, and with it greater probabilities of approaching the Canary Islands, as well as “much more intense episodes”.
But other studies even point to an improvement in the atmospheric and oceanic conditions encountered by tropical cyclones as they head towards Europe.
Even if “nothing can be said yet”, this expert points out that cyclones with tropical characteristics have “considerably increased” over the past ten, fifteen years and we can deduce that the conditions are more and more favorable for they end up touching the Canary Islands or the Iberian Peninsula.
One of these conditions is the sea temperature which, according to the meteorologist AEMET, should increase in the Atlantic; then there are atmospheric ones (humidity, shear, instability, atmospheric dynamics), on which there is “greater uncertainty”.
there is no shield
What he least doubts is that “the idea that the Canary Islands are oblivious to the arrival of tropical cyclones must be dismantled”.
The storm ‘Hermine’ came to show that the Canary Islands “have no shield”, since the physico-mathematical models with which meteorologists work treated it as one of the possible scenarios that it would end up having a full impact on the islands.
This expert recalls that the Canary Islands generally benefit from unfavorable conditions for the advance of tropical storms, but “in time” they can be favorable.
The question, he points out, is whether they are becoming more favorable and whether this is linked to climate change.
And if I had to bet, he insists, I would because over the years “it may be more and more normal” and even without excluding “wider approaches”.
Aware that his message can be described as “catastrophist”, Juan Jesús González Alemán maintains that scientists have an obligation to “give as much information” as they have.
Another thing, he adds, is whether Category 4 or 5 hurricanes will hit the Canary Islands or the peninsula, like in the United States.
He considers that it is “very unlikely”, but in any case “something secondary” because a tropical storm like ‘Hermine’, if it had arrived “in better conditions” would have left “a very noticeable, problematic impact and disturbing”, taking into account the orographic conditions of the islands.
“We were lucky that in the end the rains weren’t so intense because the cyclone didn’t come so close. And yet, it had a remarkable impact,” he observes.
Juan Jesús González Alemán insists that tropical cyclones are “very complex phenomena that require extensive research, not like heat waves or others that may have a clearer relationship with climate change”, and that in the task force in which he shares space with world hurricane experts “we’re not clear on things.” EFE