Global warming and poor construction trigger devastation due to rain

He global warming exponentially increases the probability of torrential rains in the Mediterranean and Libyawhere damage caused by rainfall is aggravated by building in flood-prone areas or the lack of maintenance of infrastructure, especially dams.

According to analysis by an international team of climatologists from the World Weather Attribution (WWA) network, warming caused by human activity has multiplied the probability of torrential rains by 10 in Greece, Bulgaria and Turkey, and by 50 in Libya.

The study also concludes that the destruction caused by the heavy rains has been much greater due to “human factors”such as construction in flood-prone areas, poor dam maintenance, deforestation or the consequences of the conflict in Libya.

Spain, exposed to repetition every 40 years

In early September, an isolated upper-level depression (DANA) and Cyclone Daniel left large amounts of rain for ten days in countries such as Spain, Greece, Bulgaria, Turkey and Libya.

Torrential rains caused massive flooding across the region, killing four people in Bulgaria, five in Spain, seven in Turkey and seventeen in Greece.

The biggest disaster occurred in Libya, where floods caused two dams to collapse and more than 4,000 people were killed and 10,000 missing, according to WWA.

To quantify the effect of global warming on heavy rainfall in the region, scientists have analyzed climate data and computer model simulations to compare the current climate, following global warming of approximately 1.2°C since the end of the 19th century, with the climate From the past.

The analysis was divided into three regions: northeastern Libya, which concentrated much of the rain in the country; Greece, Bulgaria and Turkey, where the analysis focused on maximum rainfall for four consecutive days; and Spain, where most of the water fell in just a few hours.

In the case of Libya, scientists conclude that climate change caused by greenhouse gas emissions has increased the probability of torrential rains by up to 50 times and the amount of water by 50%.

However, with the current climate, the phenomenon remains extremely rare and can only be expected to occur in the region once every 300/600 years.

In the case of Greece, Bulgaria and Turkey, the analysis indicates that climate change increased the probability of torrential rains up to 10 times, with up to 40% more precipitation.

In this area, the phenomenon is “reasonably common”and can be expected to occur approximately once every 10 years.

For central Greece, where most impacts occurred, the event is less likely and is only expected to occur once every 80/100 years.

In Spain, where most of the rain fell in a few hours, scientists say that such intense rainfall can occur once every 40 years, although, according to the same source, they have not been able to do a complete attribution analysis because climate models available poorly represent intense precipitation on time scales of less than one day.

Although we cannot completely rule out the possibility that climate change has not affected the probability and intensity of phenomena like these, scientists assure that it has done so for several reasons, such as the fact that increased temperatures usually cause more intense rains.

One of the main conclusions of the study, WWA adds, is that the large impacts observed in some regions were due to a combination of high vulnerability of the population and its exposure to the phenomenon.

In the affected area of ​​central Greece, most cities and communities and much of the infrastructure are located in flood-prone areas.

In Libya, the combination of several factors, such as a long-term armed conflict, political instability, possible design flaws and poor maintenance of dams, contributed to a catastrophe that has caused “extreme destruction.”

Source: EFE