Jorge Olcina
Professor of Regional Geographical Analysis at the University of Alicante
Is the report of good quality? Are the conclusions backed up by solid data?
“Yes, the report is of good quality. The World Meteorological Organisation is a body that rigorously examines issues relating to the atmosphere and related fields such as hydrology, glaciology and oceanography, as it has effective monitoring systems in place across the globe. The report’s conclusions are supported by solid data.
There are areas of Spain (the west and north-west) where rainfall this summer has fallen by 75 per cent (below average). What does this mean in climatological and human terms? We have experienced one of the driest and hottest summers in recent decades in Spain, and this has had significant effects on water levels. Curiously, the areas most vulnerable to drought in Spain are the regions in the north of the peninsula, as they are not prepared for short but intense droughts (one or two months without rain). Consequently, drought alarms are sounding and supply problems are arising in towns that have not adapted their urban water management plans to the new climatic conditions that are emerging – conditions characterised by greater irregularity in rainfall”.
What do drought episodes such as this summer’s reveal about the future climate in Europe?
“That the rainfall pattern is changing. So-called ‘express droughts’ are becoming increasingly frequent; that is, short-lived (2–3 months) but very intense droughts accompanied by high temperatures that increase water evaporation. This is what has happened across much of Europe this summer and has also affected the north of our country. These are areas accustomed to regular and continuous rainfall throughout the year. Consequently, when there are two or three months of rainfall well below normal, they begin to experience problems with agricultural and, in particular, urban water supplies.”
How can it be that Spain’s water reserves are at 62 per cent of their capacity whilst there is widespread concern about drought?
“Because the overall figure for the country as a whole masks very diverse regional and local realities. As has been pointed out, the rainiest areas of Spain (the Cantabrian regions and the Pyrenees) are the least prepared to withstand short-term droughts such as the one we have been experiencing in our country since last May. Their urban water supply systems are not equipped to cope with this new climatic reality. They rely exclusively on water from rainfall, against a backdrop of increasingly erratic rainfall, and this heightens their vulnerability to drought. By contrast, the south-east of the Iberian Peninsula – where the lack of rainfall and the impact of severe droughts are greatest – has a water supply system organised around the use of multiple sources (rivers, aquifers, desalination, reuse), which enables it to cope with several months of rainfall well below normal levels.”
What are the implications of the report’s findings?
“All of this compels us to review our water planning to adapt it to the new climatic reality we are experiencing, with higher temperatures, very hot summers that increase water evaporation, and more irregular rainfall. Spain must begin to plan its water resources and usage within the new climate change scenario by prioritising water reuse and relying less on direct rainfall. Cities must expand their water storage reservoirs to be able to cope with weeks of little or no rain. If this is not done, we are doomed to live in a permanent state of drought alert, especially in the rainiest areas of Spain in the north of the peninsula. We need to develop multi-source systems that are not exclusively dependent on rainfall. As I say, the reuse of treated water and the exchange of water flows between the countryside and the city are solutions that are easy to implement and would reduce our country’s vulnerability to droughts.”