Bob Ward: What's climate change got to do with Greek wildfires?

The deadly wildfires currently sweeping the Attica region of Greece may have been started deliberately, but they are now being driven by high winds and an abundance of dry wood.

Greece is prone to wildfires (Picture: Aris Messinis/AFP)

Wildfires are relatively common during the summer months across southern Europe.

A team of Greek researchers in 2016 found that most wildfires in Greece are associated with a combination of high atmospheric pressure systems located to the north and north-west, and lower pressures over the Eastern part of the Mediterranean Sea.

This atmospheric pressure pattern is known to favour the development of the local Etesian winds, which make fires spread rapidly.

But there is also evidence that climate change is causing the risks to rise.

We do not know yet if there is a trend in the incidence of high winds in southern Europe.

However, many years of dry conditions without wildfires tend to make the risks greater.

We know that periods with little or no rain are becoming worse along the northern Mediterranean countries.

A study by Italian researchers published last year concluded that the frequency and severity of drought conditions have increased in southern and eastern Europe in summer and autumn since 1950.

At the same time, droughts have become fewer and weaker in Northern Europe in winter and spring.

As the planet warms due to rising levels of greenhouse gases in the atmosphere, patterns of rainfall around the world are changing.

Basic physics indicates that as the atmosphere warms up, it can hold more water. As a result, we expect both the distribution and intensity of drought conditions and heavy rainfall to change, but the extent varies from season to season and region to region.

Climate models indicate that summer drought conditions in Greece and other countries of southern Europe will worsen still more over the coming decades, and the number and intensity of wildfires will grow.

Bob Ward is policy and communications director at the Grantham Research Institute on Climate Change and the Environment at the London School of Economics and Political Science