Was that a big wildfire?
Tracking data on the scale and impacts of wildfires across the world.
There were some really big wildfires last year. I did a deep-dive on several of them – in Canada and Greece – on this Substack. See the charts below.
Understandably, wildfires were in the media a lot. But I often struggled to put random quoted numbers in perspective. Is 14 million hectares of burn a lot for Canada? Is 150,000 hectares a record in Greece? I had no clue before hunting down the historical data.
In the midst of the extremely warm summer every headline about a new wildfire felt like it must be record-breaking. Even in countries where 2023 turned out to be a low-burn year.
We can easily see completely true headlines, such as this one from the BBC – “Portugal battles wildfires amid third heatwave of the year” – and jump to the conclusion that Portugal is experiencing recording-breaking fires. This report from the BBC is not wrong in any way, but most of us struggle to put the quoted numbers in context.
Look at the data and we see that 2023 was not a particularly big year in terms of the area burned.
Without grounding ourselves in the data, people can be pulled in two directions. They make the standard “it’s summer – we always have wildfires here” claim, even when the fires are exceptional and it’s not a “normal summer” at all. Or they see headline after headline and assume that the world is being set alight.
Data helps us to test both of those reactions.
A new page to track wildfires across the world
My colleague Veronika Samborska and I have built a new page on Our World in Data that helps people follow country-by-country data on wildfires.
Most of the underlying data is sourced from the Global Wildfire Information System (GWIS). This is a joint initiative of the Group on Earth Observation (GEO) and Copernicus, the Earth observation component of the European Union’s space program. They deserve all the credit for monitoring, and making this data available.
The data for 2024 will be updated weekly, so you can track the area burned, and emissions, as the fire season progresses.
I’ve included a few of the charts below for context, but you can find many more, with further explanations on our complete Wildfire page.
Limitations of the data
We shouldn’t pretend that this data is perfect for tracking wildfire impacts. There are three main caveats to keep in mind.
First, the data only goes back to 2012. This is not enough to assess long-term trends in wildfire burn. Sources that track wildfires globally and use consistent methods are hard to rare. GWIS is arguably the most comprehensive in terms of geographical coverage. For some countries, I’m sure there are multi-decadal records available.
Second, data is aggregated at the national level. It doesn’t tell you whether the West or East coast, or some specific region within a given country is experiencing record fires.
Third, the amount of area burned doesn’t tell us about how human impacts. A moderate fire could be more damaging than a large one if it’s near dense populations. For example, while the total area burned in Portugal was below average last year, wildfires in southern Portugal did sweep close to the tourist spot of Algarve, with major impacts on populations there.
Despite these limitations, I think this dataset is a useful place to start to get some context over the wildfire season. I’m sure I’ll be using it in some posts this summer (but hopefully with no exceptional rates to report).
Please keep up this important work. 🙏🏼
Thank you Hannah, very insightful work.
Some deductions:
- The fires in Greece were a tragedy and newsworthy one, as no one likes tourists areas to be hit or ancient olive groves to go up in flames. But in the global scheme of things, they were a rounding error.
- Africa matters. It seems half the fires are in Africa. Is this because it has the most tropical and sub tropical forests?
- Europe's figures are surprisingly large. Typically more than USA+Canada, despite this being a smaller continent. Where are these all? Are remote Russian forests regularly going up in flames and no one notices?
- Will the data separate out what I think are the three types of wildfires:
1. Unintended destructive fires. These of course are the ones that make the headlines.
2. Illegal (or unethical) land clearing, whether government sanctioned or not.
3. Land management fires, often to clear scrub around fire resistant trees, of the type widely used in Australia over the last 10,000 years.