Extreme weather events
What are extreme weather events and why are there ever more of them?
In recent decades, extreme weather events have become more frequent, intense and prolonged across many regions of the world. According to the Intergovernmental Panel on Climate Change (IPCC), human-induced global warming is increasing the likelihood of extreme events such as heatwaves, droughts, torrential rainfall and tropical cyclones.
In the summer of 2021 an extreme heatwave in the eastern Mediterranean — with temperature of around 47 ºC in Greece lasting several days — was followed by a series of wildfires that devastated thousands of hectares. The shocking images brought back memories of those of merely a year earlier from Australia. And the fact is that over the last few years the disasters caused by extreme weather phenomena have been an increasingly habitual occurrence, be it in the form of heatwave, flooding or drought.
Climate change and extreme weather events
Why are extreme weather events becoming increasingly common? The Intergovernmental Panel on Climate Change (IPCC) has made the cause clear. In its most recent assessment reports, it once again identified climate change. It also blamed humankind for the increase of greenhouse gas (GHG) emissions which, in turn, are partly responsible for the rise of temperatures worldwide.
The panel of experts warns that if CO2 emissions are not reduced over the next few decades, the increase of temperatures on a worldwide level will exceed the threshold established in the Paris Agreement. As a result, extreme weather phenomena will continue being more widespread, the Arctic icecap will shrink — for example, ice floes and glaciers — sea levels will rise and the loss of biodiversity will be inevitable. UN Secretary General Antonio Guterres sums the situation up as follows: "The alarm bells are deafening and the evidence is irrefutable".
Types of extreme weather events
Extreme weather events can be grouped together as follows:
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Heatwaves
Unlike heatwaves, this phenomenon, which causes low temperatures to persist for several days, has become less frequent according to the IPCC. However, this does not rule out unusual events.
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Colnd snaps
Unlike heatwaves, this phenomenon, which involves several days of low temperatures, has become less frequent, according to the IPCC. However, this does not mean the end of unusual situations, such as Storm Philomena, which brought Spain to a standstill for several days.
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Tropical cyclones
According to the IPCC, their frequency has increased in recent decades. In addition, they are becoming more destructive as higher-category hurricanes occur. This could be linked to the rise in sea surface temperatures.
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Droughts
The lack of rain in certain areas of the world, such as the Horn of Africa, is increasingly pronounced, thereby prolonging this phenomenon and forcing thousands of people to emigrate and become climate refugees. In addition, water scarcity can also result in violent clashes.
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Torrential rains
At the same time as there may be less general rainfall due to climate change, the rain which does fall might become more intense, resulting in typhoons capable of causing extremely destructive flooding and swollen watercourses.
Compound events: when risks combine
Extreme weather events do not always occur in isolation. Sometimes, two or more hazards coincide, occur in quick succession or interact with existing conditions that worsen their impacts. These situations are known as compound events.
For example, a prolonged drought can dry out vegetation and, if it is then followed by a heatwave accompanied by strong winds, the risk of wildfires increases considerably. Similarly, intense rainfall can lead to more severe flooding when it falls on already saturated ground or coincides with rising river levels or coastal storm surges.
These events can more quickly overwhelm the response capacity of communities, infrastructure and ecosystems, meaning their impacts are often more severe than those caused by each phenomenon individually. For this reason, prevention strategies must consider not only each individual risk but also the potential interactions between them.
The consequences of extreme weather events
Extreme weather events have serious consequences with respect to both human and animal life. Some of these are reviewed below:
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Wildfires
Heatwaves, which seriously dry out the ground, often trigger virulent wildfires that affect entire communities, destroying homes and damaging health due to smoke inhalation. Furthermore, the impact on ecosystems is such that some of them never recover.
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Flooding
The IPCC highlights the high probability that monsoon rainfalls will increase in the medium and long term, especially in South and South-east Asia, causing terrible floods. This will have especially serious consequences for coastal cities.
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Famines
Those sectors that depend on a certain degree of climate stability, such as agriculture, are seeing their production and performance levels undermined, thereby generating food insecurity in certain areas. The EU points out that these phenomena, in turn, could well cause a deterioration in water quality.
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Climate migrations
According to Oxfam, more than 20 million people per year are forced to abandon their homes as a consequence of the effects of climate change, which include extreme weather phenomena.
In the majority of cases, these consequences are severe losses of human life and economic ruin. According to the 2021 Climate Risk Index prepared by the Germanwatch organisation, eight of the ten countries most affected by these phenomena have low-income economies. With that in mind, the United Nations Environment Programme (UNEP) estimates that, by 2030, adapting to climate change and tackling the damages it will cause will cost developing countries between 140 and 300 billion dollars a year. What's more, these events also affect ecosystem biodiversity, putting numerous species under threat.
Examples of extreme weather events
In recent years, there has been an upsurge of extreme weather events that have wreaked havoc in different parts of the world. In adition to the aforementioned wildfires that devastated the eastern Mediterranean, the most recent of these include:
- Flooding in the Valencian Community (Spain). In October 2024, a DANA (isolated depression at high levels) brought torrential rainfall and flash floods to the province of Valencia and other areas of eastern Spain. The event caused hundreds of fatalities, significant material damage and highlighted the vulnerability of urban areas to extreme rainfall.
- Flooding in Rio Grande do Sul (Brazil). Between April and May 2024, persistent rainfall caused the worst flooding recorded in the Brazilian state in more than eight decades. Thousands of people were evacuated and numerous infrastructures were severely affected.
- Hurricane Beryl in the Caribbean and North America. In 2024, Hurricane Beryl became the earliest recorded Category 5 hurricane in the Atlantic. Its rapid intensification and impact across several Caribbean islands and the southern United States demonstrated the destructive potential of the most intense tropical cyclones.
- Record-breaking heatwaves. In recent years, exceptionally high temperatures have been recorded across Europe, North America and Asia, with new temperature records, an increase in wildfires and significant impacts on public health, agriculture and water resources.
- Prolonged droughts. Regions such as the Mediterranean, the western United States and the Horn of Africa have experienced extended periods of low rainfall that have affected water supplies, agricultural production and ecosystem conservation.
How can you prepare for extreme weather events?
Although it is not possible to prevent extreme weather events from occurring, it is possible to reduce the risks they pose through proper planning and prevention. Both public authorities and the public play a key role in minimising their consequences and protecting people, property and the environment.
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Follow official alerts and advice
Before, during and after an episode of extreme weather, always check the information provided by meteorological services and civil protection authorities. Early warnings allow you to anticipate risky situations and take preventative measures.
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Draw up a family emergency plan
It is advisable for all members of the household to know how to respond to a flood, a heatwave, a wildfire or a severe storm. Establishing meeting points, evacuation routes and means of communication can be crucial in an emergency.
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Protect your home and check its condition
Carrying out regular maintenance on roofs, gutters, drains and nearby trees helps to minimise damage during episodes of heavy rain or strong winds. If your home is in an area at risk of flooding or fire, it is advisable to take additional protective measures.
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Prepare a basic emergency kit
Having an emergency kit makes it easier to cope during the first few hours following an extreme weather event. It should include drinking water, non-perishable food, a torch, batteries, portable chargers, a radio, a first-aid kit, important documents and the family’s regular medication.
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Avoid unnecessary travel
During warnings of torrential rain, snowfall, strong winds, heatwaves or wildfires, it is usually safest to stay in a sheltered place and follow the authorities’ instructions. If you absolutely must travel, it is advisable to check road conditions and weather forecasts in advance.
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Take out appropriate insurance
Regularly reviewing the cover provided by your home or business insurance can help you cope with damage caused by extreme weather events. In some countries, specific compensation schemes are in place for certain extraordinary risks.
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Reduce your exposure in high-risk areas
Whenever possible, avoid staying in or carrying out activities in particularly vulnerable areas during periods of adverse weather, such as riverbeds, ravines, coastal areas exposed to heavy swells or forested areas with a high risk of fire.
Preparing in advance does not prevent extreme weather events from occurring, but it does help to reduce their impact on people, infrastructure and the environment.
Iberdrola and climate resilience: anticipating, adapting and protecting infrastructure
Extreme weather events also pose a risk to energy infrastructure. Storms, strong winds and heavy snowfall can damage power lines; torrential rain and flooding can affect substations and transformer stations; and extreme temperatures or fires can hinder the operation of facilities. At the same time, the increasing electrification of society means that ensuring continuity of supply is becoming ever more important.
At Iberdrola, we incorporate climate risks into the planning, design and operation of our infrastructure. The measures adopted include the digitalisation and automation of networks, the undergrounding of power lines in particularly exposed areas, the management of vegetation adjacent to power lines, and the use of materials and designs that are more resistant to high temperatures, flooding and fires.
We also use predictive and monitoring systems. Tools such as Meteoflow enable us to anticipate certain weather events and organise human and technical resources in advance, whilst the Domina system helps to detect potential faults and improve our response to incidents. These tools are complemented by emergency plans, early warning systems and inspections using drones and LIDAR technology.
These measures demonstrate that climate resilience is not simply a matter of repairing damage in the wake of a disaster. It also requires anticipating risks, adapting infrastructure and having systems in place capable of maintaining or rapidly restoring essential services. In the electricity sector, such preparedness is essential to protect the public and prevent extreme weather events from triggering prolonged disruptions to hospitals, transport, communications, homes and businesses.