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The weather conditions that contributed to the wildfires that struck Los Angeles last January – causing the deaths of numerous people and the destruction of many homes – were fueled by climate change.

T
his is confirmed by a preliminary study from the World Weather Attribution (WWA), an international research group that brings together climate experts. According to the report, the weather conditions that favour such disastrous events have become much more likely due to climate change. Established in 2015, the WWA focuses on a new branch of climatology known as "attribution science", which investigates the links between climate change. and extreme weather events, trying to quickly answer the question "is climate change involved?". The scientific community now has enough data to relatively quickly contextualise, albeit preliminarily, individual weather events, placing them within the broader and more complex phenomena related to climate. Furthermore, the increased amount of data has made it possible to definitively confirm what had already been hypothesised decades ago, thanks to the early climate prediction models: namely, that the rise in the Earth's average temperature – caused by greenhouse gas emissions largely from human activities – is a key factor in increasing the frequency and intensity of extreme atmospheric events.

Attributing a single extreme weather event to climate change was much more complicated until recently, due to the high number of variables involved. Generally, research groups compare what happened in a given period with what would have been expected, based on historical data and simulations. Based on the differences observed and other factors, they estimate the likelihood that a particular event was influenced by climate change. However, these studies, in the past due to a lack of data, required long periods to be conducted and reviewed, and often by the time they were published, the news cycle had shifted attention to other current issues.

Another preliminary analysis conducted last year by the WWA, regarding the heavy rains that in September 2024 caused the flooding of several rivers in Central Europe, concluded that this extreme event was exacerbated by climate change. The floods caused enormous damage in Romania, the Czech Republic, Poland, and Austria. Storms, prolonged droughts, heatwaves in some areas, and below-average temperatures in others: these are just some of the extreme weather events made more likely by climate change, which in turn contribute to uncontrolled wildfires, flooding, or limited access to water in different parts of the planet, among other issues, with significant repercussions for local populations.

February 2025

Japan

Out of control fires

+5000

Evacuated people

+70

Burned houses
January 2025

California

Out of control fires

29

Killed people

+6000

Burned houses
September 2024

Romania

Flooding

5

Killed people

+5000

Evacuated houses
May 2023

Italy

Flooding

17

Killed people

8.8 MLD €

Estimated damages

However, weather events and climate events should not be confused. A distinction that scientists emphasize is that between "weather" and "climate", precisely to avoid drawing hasty conclusions from individual extreme events in the absence of data. In recent years, analyses of individual phenomena have improved thanks to the efficiency of the models used to assess climate changes, and the ability to gather much more information and evidence about atmospheric events in various areas of the world.

Definition of

"Weather"

→ Short term

Includes the study of specific atmospheric phenomena confined in space and time.

Definition of

"Climate"

→ Long term

Includes more detailed analyses of how the effects of weather vary across the territory over decades.

Greater knowledge of climate phenomena has allowed not only governments and institutions to adopt more effective prevention measures, but also companies to develop more resilient and sustainable strategies – integrating precise models related to climate risk into their operations.

2024 was the first year in which the 1.5°C limit set by the Paris Agreement on climate was exceeded for such a long period – that is, the most important international treaty to combat global warming.

T
he surpassing of this threshold had been anticipated for some time, especially since the past year – like the last decade – was the hottest ever recorded. The reference point for assessing the trend of global average temperature is the late 19th century, when levels of industrialization were very low and consequently the release of large amounts of carbon dioxide – the main greenhouse gas – from human activities was minimal. The primary cause of the increase in global average temperature is indeed the accumulation of greenhouse gases, primarily due to the use of fossil fuels. At this rate, there is a risk that the 2°C threshold, set by the Paris Agreement as the maximum limit to avoid even more catastrophic consequences related to climate change, will also be exceeded in the future. An additional half degree would further increase the risk of increasingly frequent disastrous weather events.

Recently, the World Weather Attribution published a preliminary analysis dedicated to the effects of the exceptional heatwave that struck much of Europe between late June and early July 2025, estimating that – in this case – the number of deaths related to excessive heat would triple. This trend fits into a broader context of climate alteration at a global level, whose effects manifest nationally and locally not only with an increase in health risks but also with significant impacts on ecosystems and infrastructure. In the last forty years, the number of extreme weather events has indeed tripled, and since 2015 there have been over 400 episodes of strong winds and snow that have caused disruptions and various types of damage, particularly to the electrical system.

In the infrastructure sector, the risks posed by climate change have already shown their impact on activities and services. In recent years, the National Transmission Network * managed by Terna has recorded a series of extreme events with consequent impacts on the continuity of electrical service. The electrical system presents an increasing management complexity that, along with the rising frequency and severity of adverse climatic events, necessitates constant monitoring of the safety, adequacy, and resilience* of the system.

he National Transmission Grid (NTG) is the infrastructure managed by Terna that enables the transport of high and very high voltage electricity across the entire national territory, from production plants to local networks, which then distribute it.

Resilience is the ability of the system and its components to absorb and withstand stresses that have exceeded the system's limits and to return to normal operating conditions quickly and efficiently.

2024

Glaciers

The health of Italian glaciers, and not only them, is very delicate: their existence is threatened by the effects of climate change.

In this context, having a sustainable electrical infrastructure capable of integrating and utilizing "clean" energy sources, and resilient to potential damage caused by the increasing intensity of weather events, becomes one of the enabling factors in responding to climate change. In addition to planning and developing a robust network, it is essential to leverage the potential offered by the digitalization of infrastructures to better address the climate crisis and ensure the safe and efficient operation of the electrical system following severe weather events. In the context of climate assessment, since 2020, Terna has adopted the "Resilience Methodology": a prospective analysis tool designed to anticipate the evolution and impacts of climate change in the coming decades. This methodology integrates a probabilistic approach, essential for assessing failures and multiple contingencies, as well as the risk of unprovided energy in the event of extreme weather events. This allows for more effective and efficient planning of interventions aimed at strengthening the resilience of the electrical grid.

The three key elements of the Resilience Methodology

Development of predictive climate scenarios

→ With the aim of identifying areas of the territory most exposed to the effects of severe weather events of various kinds, associating with them the relative probability of occurrence.

Assessment of the vulnerability of components of the electrical lines

→ The components of electrical lines can be subject to direct and indirect stresses caused by severe weather events. In this case, the analysis is conducted through the determination of specific vulnerability curves defined using real technical-orographic parameters.

Probabilistic approach "n-k

→ It is used for the analysis of multiple and simultaneous disruptions caused by weather events, in order to quantify the probability of occurrence of such contingencies and assess their impact on the portion of the electrical system exposed.

Over the years, the Resilience Methodology has undergone continuous developments and refinements, aiming to consolidate analyses related to climatic events such as snow and strong winds, and to extend assessments to phenomena related to hydrogeological instability. In the 2024 Safety Plan, Terna has further strengthened investments and initiatives aimed at better interpreting its role as an enabler of the energy transition. The increase in the resilience of the grid in response to the intensification of extreme weather events continues to be pursued through prevention, restoration, and monitoring actions, supported by advancements in digitalization, with the intent to ensure increasingly high standards of continuity and safety of electrical service.