Climate Change and Forest Fire Link

Climate Change and Forest Fire Link

Scientists has noted that human-induced climate change promotes the conditions on which wildfires depend, enhancing their likelihood and challenging suppression efforts. The update focuses on the ongoing wildfires in the western US and the bushfires that ravaged southeastern Australia in 2019-2020.

Factors that influence fire weather

The Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), which was published in 2013, identified a few factors that could influence the way wildfires play out.

These include global increase in average temperatures, global increases in the frequency, intensity and extent of heatwaves (breaching of historically extreme temperature thresholds) and regional increases in the frequency, duration and intensity of droughts.

There are several elements of weather that must be considered.  They are:

1. Temperature: Air temperature has a direct influence on fire behavior because of the heat requirements for ignition and continuing the combustion process.
2. Wind: Wind has a strong effect on fire behavior due to the fanning effect on the fire. Wind can change direction and intensity throughout the day. This change can be very abrupt surprising the burner that is not alert.
3. Stability of the atmosphere: Moisture in the form of water vapor is always present in the atmosphere. And - the amount of moisture that is in the atmosphere affects the amount of moisture that is in the fuel.
4. Relative humidity: Moisture in the form of water vapor is always present in the atmosphere. And - the amount of moisture that is in the atmosphere affects the amount of moisture that is in the fuel. 
5. Precipitation: Precipitation (rain or snow) has a direct and immediate effect on fuel moisture and relative humidity. Temperature usually drops as well and the winds become calm.
6. Cloud development: When moisture is added to the atmosphere or the air temperature is lowered, the relative humidity increases. When it increases to the saturation point, the moisture begins to combine into droplets.

New analysis about Forest Fire

Scientists are wary of attributing any single contemporary event to climate change, mainly because of the difficulty in completely ruling out the possibility of the event having been caused by some other reason, or a result of natural variability.

However, in the results of the new analysis, the authors note that natural variability is superimposed on the increasingly warm and dry conditions that have resulted from climate change, which has led to more extreme fires and more extreme fire seasons.

Further, they note that there is an “unequivocal and pervasive role of climate change in increasing the intensity and length in which fire weather occurs”.

Significantly, the authors have said that while land management is also likely to contribute to the wildfires, it does not alone account for the recent increases in the extent and severity of the wildfires in the western US and in southeast Australia.

What happened in Australia last year?

Last year, photographs of Australian towns and villages that were ravaged by the bushfires made global headlines.

While bushfires are routine in Australia in the summer months, the scale and intensity of the fires last year was unprecedented.

The fires killed thousands of animals and impacted more than 10 million hectares of forest land, which is an area the size of South Korea.

Scientists suggested at the time that there was strong evidence to suggest that the bushfires, which were especially fierce last year, could be linked to climate change.