Climate change and fire season

Runaway fires feature regularly in the news, with stories so far this year covering catastrophic wildfires in North and South America, the UK (Scotland), and Canada. In early June 2023, a Reuters article reported that “Canada is on track for its worst-ever year of wildfire destruction as warm and dry conditions are forecast to persist through to the end of the summer after an unprecedented start to the fire season… Blazes are burning in nearly all Canadian provinces and territories.”

A year when the world burned

This follows a 2022 that saw vast wildfires burning in countries across the world, from Asia, where fires in South Korea consumed almost 17 000 hectares (ha) in early March and over 9 000 ha in Russia, to Africa, where fires in Morocco and Algeria destroyed almost 8 000 ha and South America, where wildfires in the Corrientes province of Argentina near Paraguay’s borders ravaged about 900 000 ha in February. North America and Canada experienced numerous disastrous wildfires, including the so-called McKinney Fire in northern California that burned over 24 000 ha and killed four people, and the vast blaze caused by the merging of the Hermits Peak Fire and the Calf Canyon Fire in New Mexico, that had charred almost 140 000 ha by August 2022. Outside of the western US, Alaska leads in wildfire activity, with over 1,2 million ha burned last year.

It was also a catastrophic year in the European Union, the second-worst wildfire season since 2000 when European Forest Fire Information System (EFFIS) records began. Damages in 2022 exceeded those of 2021 and are only surpassed by those of 2017, with 45 countries suffering 16 941 fires that burnt 1 624 381 hectares. Excluding war-torn Ukraine, Spain was the most affected by wildfires with a total of 315 705 ha. This is three-and-a-half times more than in 2021. Romania (16 2518 ha), Portugal (11 2063 ha), Bosnia and Herzegovina (76 473 ha) and France (74 654 ha) were countries that were severely affected.

Changing weather patterns

Climate change and global warming are changing weather patterns across the world, with summers becoming longer, hotter and dryer, but also in some regions wetter with extreme storms and dramatic flooding. When there is drought, the drier conditions reduce the amount of moisture in vegetation, increasing the risk of it igniting when exposed to heat (from lightning, an unattended campfire, a dropped match or cigarette, a hot exhaust pipe etc).

Multiple studies indicate that climate change has led to longer fire seasons around the world as well as increasing the frequency of wildfires and the extent of the affected (burned) area. An example is the five-time increase in the extent of areas damaged by California wildfires from 1971 to 2021, with scientists warning that it could increase by as much as 50% by 2050.

The local fire season

South Africa experiences different fire seasons, with the western areas experiencing a winter rainfall period unlike the dry winters of the eastern parts. In May, after the close of the Western Cape fire season (their very hot and dry summer), fire-fighting resources were moved to more high-risk areas. According to Working on Fire, 21 aerial resources in the Cape were relocated to northern and eastern provinces (Mpumalanga, Limpopo, Eastern Cape and KZN), in preparation for the winter fire season in these provinces. Interestingly, the Eastern Cape has two fire seasons: the winter fire season, which occurs from June to October in the eastern part of the province, and the summer fire season, which takes place from December to April in the western part.

Simon Thomas of KwaZulu-Natal Fire Protection Association says, “The KZN fire season is showing a trend of starting later, but this year it’s a difficult one to gauge. El Niño is on its way, and we will only really feel its effect towards the latter part of the year. The vegetation is currently still very green, but green is not always a good thing at this time of the year. That means high fuel loads and a late start to burning season. This could spell disaster as landowners will have a problem reducing the fuel load before the cut-off date for burning.” He notes that “KZN FPA has its own aerial resources, paid for by private members. These include six spotter planes, eight SEATs [single engine air tankers or bombers] and two choppers based at bases in Shafton, Richmond, Weza, Kwambo and Melmoth.”

Willem Oosthuizen of Firehawk, the locally-developed wildfire monitoring and detection system, says, “While the local fire season started to move in general to later in the year I think this is mostly just our natural cycles that we go through and I believe it has started to move back towards June again. I’ve seen the fire season move to later or start earlier – I can’t say it has shifted solely in one direction; we have had horrific June years and sometimes horrific November years. They shift with the El Niño and La Niña cycles. There are also large outliers, like a catastrophic fire in the Karkloof that took place just before Christmas in 2019.”

Gareth Smallbones, Manager: Agriculture at Safire agrees that it is difficult to determine whether fire season patterns are changing, although he believes that fire seasons may be extending for longer periods. “We have had three very good winters with low losses, and we were hoping for a wet winter this year,” he says. “However, we have already experienced days with severe berg wind conditions that led to ‘red’ no burning days, which is unusual for June.”

In April this year, AccuWeather forecasters released their annual wildfire predictions, led by veteran meteorologist Paul Pastelok. He explained, “A fire season is more defined on its impact to the public and not by the acreage burned. Forecasting wildfire activity can be challenging for meteorologists, but not because of the weather. Predicting wildfire numbers and acreage is very difficult, as nearly 90% of fires are caused by humans. Fires started by people are nearly impossible to predict.”