The Need For Change: Fire!

There have been two major forest fires in Northern America in 2014, a light relief compared to the five major forest fires of 2013 and the seven of 2012. The first in 2014 was in Washington and within four days of the fire starting 300 homes had been destroyed, the second was in British Columbia and was the largest in British Columbia since 1982 and destroyed over 300,000 acres of land. This is obviously a problem. Forest fires are a big problem when they have the ability to destroy so much land and harm so many people and the effect of changing climate on forest fires is something that needs to be considered.

Forest Fire, Bitterroot National Forest, USA. 2000.
Source: Reddit

Wildfires have a large range of contributing factors including temperature, humidity, wind and the location of lightening strikes. However human factors such as fuel and land management can contribute to wildfires too. (Westerling, 2003) The atmospheric conditions conductive for wild fires are expected to change with climate change - thus the patterns and frequency of wildfires are also subject to change. But how?

A recent study by Tang et al to be published early January next year has looked into the effects of climate change on the atmospheric conditions that are associated with wildfires. They've done this using simulations from multiple regional climate models and used a comparison between the current climate and the predicted climate of 2050 to look at the differences. To compare the atmospheric conditions Tang et al have used the Haines Index.

Definition: Haines Index - "a measure of how conductive the atmosphere is to potential extreme or erratic fire behaviour based on atmospheric stability and moisture" (Haines, 1988) hence can be split into two parts a humidity component and a stability component. A value of 5 or 6 on the index signals a high level of potential for wildfires. (Tang, 2015)

The models show that by 2050 there is relatively little change in spatial and seasonal patterns - meaning regions for erratic wildfires at present will remain regions for erratic wildfires in the future. Key regions have been highlighted by the paper such as Intermountain West, High Plains and the Gulf Coast region, hopefully the results of the simulations will have some influence over future land use planning in these high risk areas to help accommodate with the upcoming climate change. The models also identified an increase in the percentage of days with a high HI index and also an increase in duration of successive days with high HI indexes. (Tang, 2015) These increases in HI index are representative of an increased risk of wildfires, meaning with increased climate change there can be expected higher chance of wildfires. Hence providing mounting evidence for the detrimental effect of climate change in the US and the need for a big change!

Source: Giphy