The word ‘apocalyptic’ is overused these days but that seemed to be the only description that fitted the scenes in eastern Spain around Valencia last week after almost a year’s worth of rain fell in just four hours. Streets were turned into raging torrents that carried cars away and left them piled up, twisted and broken. At least 200 people have died and the final number could be much higher.
Amsterdam, New Orleans, Venice, Kolkata – there are plenty of cities which are regularly mentioned as liable to flooding or even eventual submersion as sea levels rise. But I can find no mention anywhere of Valencia as a particularly at-risk location. That’s what makes this so terrifying. It would be exaggerating to say ‘this could happen anywhere’, but certainly, it seems that many towns and cities might be vulnerable to more serious flooding events than we have imagined.
The disaster in Spain was caused by a particular weather phenomenon. This is from CNN. ‘The torrential rain was likely caused by what Spanish meteorologists call a “gota fría,” or cold drop, which refers to a pool of cooler air high in the atmosphere that can separate from the jet stream, causing it to move slowly and often lead to high-impact rainfall. This phenomenon is most common in autumn’.
But this year we have seen record temperatures in the Mediterranean Sea, which reached 28.47C in mid-august. This facilitates a greater uptake of moisture in the air – as does higher air temperature - so when it does rain in the autumn as the atmosphere cools, it dumps more water in a shorter period of time. Climate change certainly exacerbated the problem.
AP news reported this. ‘Human-caused climate change made Spain’s rainfall about 12% heavier and doubled the likelihood of a storm as intense as this week’s deluge of Valencia, according to a rapid but partial analysis Thursday by World Weather Attribution, a group of international scientists who study global warming’s role in extreme weather’.
Spain has also seen drought conditions this year, which means the ground is dried out and solid, and when it does rain, the earth can absorb less water per minute because it is baked hard. Then there are the purely human-created issues. More open ground in urban areas, that would have absorbed rainwater, is paved and concreted over. Homeowners turn gardens into parking areas or patios. Flood plains become housing estates or business parks. Drainage just isn’t designed to handle such huge quantities of water in a short period of time.
The effect of this disaster is not just hundreds of human lives lost, but also billions of euros of economic cost. Of course that all supports the need to keep going with our efforts to reduce emissions and de-carbonise, but nothing we do in the next few years is going to reverse what we are now seeing. We have failed to meet the 1.5C target and now the question is whether we can keep heating below about 3C by the mid-century.
Given that more extreme weather now seems a given, it becomes more and more important that business and governments take action in two key ways. First of all, planning, design and adaptation of roads, public and private buildings, water, power and transport infrastructure must take account of the likelihood of severe weather and respond to that by mitigating the risks in an appropriate manner. We need to see more policy makers, designers, architects, procurement professionals and builders asking, ‘how would what we have built handle weather outside what we have experienced before’?
Then public authorities need to think and plan much better in terms of how they respond to disasters like Valencia. The response in Spain does not seem to have been very impressive, with little sense that the regional or national government were at all prepared for this. Five days after the event, the government announced that 10,000 troops would be deployed. By that stage, social media had already mobilised a greater number of volunteers to go and help the stricken areas. So the authorities need to think more seriously about how to respond and indeed how to combine official and voluntary assistance .
We can’t stop these events, that much is clear, and even with better adapted infrastructure, there will be more disasters. So we better improve the way we react and handle them once they have occurred - because sadly, we’re going to see more of this.
(Photograph from Wikipedia https://commons.wikimedia.org/wiki/File:2024-11-02_Voluntaris_per_netejar_cam%C3%AD_de_Sedav%C3%AD_05.jpg)