ASviS provides an interesting summary of the effects of climate change, made evident by the flood that severely affected the city of Valencia in Spain. This occurred about a month after the violent floods in Romagna and Bologna, and almost simultaneously with the one in Catania. These are now phenomena that occur more and more frequently, with greater intensity and in unexpected ways. Spain, Italy, Libya, the Horn of Africa, Mozambique, China, the Philippines are just some of the countries affected by floods. However, floods are just one side of the coin when it comes to climate change. The other side is represented by the opposite phenomenon: drought. This is stated in the “State of Global Water Resources 2023” report, published in October by the World Meteorological Organization (WMO).
The report highlights that 2023 was the hottest year ever recorded, with temperatures so high and widespread that they triggered long periods of drought. According to a study by the Lancet Countdown on Health and Climate Change, the area of land affected by extreme drought has tripled since the 1980s. In 2023, 48% of the Earth’s surface experienced at least one month of extreme drought, and nearly a third of the global surface endured extreme drought for three months or more.
On the other hand, the irregular alternation of El Niño and La Niña causes strong instability and extreme weather events, with heavy rains that, as recent events have shown, can be devastating. Africa, the document emphasizes, has been the most affected region in terms of human casualties. In Libya, two dams collapsed due to a major downpour in September 2023, resulting in over 11,000 deaths and affecting 22% of the population. Floods also hit the Horn of Africa, the Democratic Republic of the Congo, Rwanda, Mozambique, and Malawi.
The report also highlights significant pressure on global water reserves, with 3.6 billion people currently facing water shortages. This number is expected to exceed 5 billion by 2050. In 2023, river flow was drier than usual, and in the same year, water inflows into reservoirs were also below normal. This situation leads to a reduction in the amount of water available for communities, agriculture, and ecosystems, further stressing global water reserves. Glaciers have also fared poorly, losing over 600 billion tons of water between September 2022 and August 2023—the worst result in the last 50 years.
“Water is the canary in the coal mine of climate change,” stated Celeste Saulo, Secretary-General of the WMO. “We are receiving danger signals in the form of increasingly extreme rains, floods, and droughts that have a heavy impact on lives, ecosystems, and economies. The melting of glaciers threatens long-term water security for many millions of people. Yet we are not taking the urgent measures needed. As a result of rising temperatures, the hydrological cycle has accelerated. It has also become more irregular and unpredictable, and we are facing growing problems of too much or too little water.”
