Last year’s wildfires caused record-breaking damage. This year looks hauntingly similar.
Keywords: Wildfires, chaparral, savanna, biome, regeneration, climate change, adaptation, precipitation, ecosystem, arid, drought, habitat
Next Generation Science Standards:
- MS-ESS2-6. Develop and use a model to describe how unequal heating and rotation of the Earth cause patterns of atmospheric and oceanic circulation that determine regional climates.
- MS-LS4-4. Construct an explanation based on evidence that describes how genetic variations of traits in a population increase some individuals’ probability of surviving and reproducing in a specific environment.
- MS-ESS3-3. Apply scientific principles to design a method for monitoring and minimizing a human impact on the environment.
Article Guide: Forest Fires Article Guide
A disaster of unprecedented scale and devastation, wildfires are raging across the continent of Australia. More than 15.6 million acres have burned, destroying 1400 homes and claiming the lives of 24 people and up to a billion animals. This comes after a record-setting 2017 fire season, in which California and British Columbia experienced some of the most destructive wildfires in history. An estimated 8.4 million acres of land burned from wildfires in the western United States that year, with the October wildfires in California was estimated to be $9 billion alone.
What has caused these historic infernos? While wildfires are natural for forest regeneration, the evidence is mounting that human-caused climate change made them more frequent, longer-lasting, and much more damaging.
A natural process
Wildfires are an important part of several biomes, including chaparral and savannas. These biomes require periodic fires every 20 to 50 years to burn down older trees and vegetation and allow for new seeds germinate and grow. Species in these biomes have developed adaptations to survive and reproduce during these natural, periodic burns. Some tree species, such as ponderosa pine, have thicker bark to protect themselves from the flames. Other trees, such as knobcone pine, require fire to open their cones in order to disperse their seeds. Without natural fires, these plant species would not be able to reproduce.
However, if fires occur too frequently, say every 10-15 years, trees and plants aren’t able to grow back and the ecosystem doesn’t have enough time to regenerate. This would not only destroy habitats, but it would allow for invasive species to move in and biodiversity to be threatened. This is why the National Park Services use what are referred to as prescribed fires to control on how long and how much vegetation is burned. Prescribed burns are started intentionally to safely allow ecosystems that require wildfires to regenerate, with park managers accounting for topography, current, and future weather patterns before ignited.
Climate Change is not helping
There no study showing a direct, causal relationship between rising global temperatures and more frequent forest fires. As such, we cannot attribute any one forest fire to climate change. However, there is a growing scientific consensus that climate change could create more favorable conditions for wildfires to start. Rising global temperatures have caused regional precipitation patterns to change, bringing drought to areas with already arid climates. Additionally, warmer winters have also reduced the snowpack in mountains, lowering the creek and river beds, further drying out the forests in the valleys below.
These factors have made for very dry forests. Just as dry, well-seasoned logs burn faster than when wet, the lack of precipitation in drier biomes allows the ignition of wildfires to happen more quickly and for the fires to last longer. The data supports this: since the 1980s, scientists have seen an increase in wildfire frequency, not just in North America, but in places such as Indonesia, Chile, and Argentina.
If there are long term changes to temperatures and precipitation, ecosystems will become permanently altered, which would make life harder on native species. Additionally, years with higher than average rainfall may not be enough to offset the effects of steadily rising temperatures. The overall trend in the western United States is becoming much drier, which combined with higher temperatures, shorter winters, and longer summers, make for more favorable wildfire conditions. Although the plants and trees are adapted to conserve water in these arid environments, they may not be equipped to survive longer periods without rain. Together, these factors have amplified the effects of forest fires, changing them from a natural, regenerative process, to being out of control and destructive to both habitats and humans.
Effects on humans:
Wildfires have proven to be extremely expensive. From 2000 to 2009 there have been an estimated $665 million per year in property damages due to wildfires. To combat the more frequent fires, local governments and federal organizations have had to increase wildfire management, further upping the cost to the taxpayer. However, economic costs are not the only factor humans have to worry about. Residents of areas where wildfires occur must be able to evacuate if the fires get too out of control or close to communities. The recent wildfire in California killed 17 people.
However, it is not too late for humans to reduce our impact on the climate by reducing greenhouse gas emissions. Switching to alternative energies and being conscious of how much energy you are using are both necessary to combat the worst effects of climate change. Also, be aware of local regulations with fire next time you go camping and conscious of weather to prevent wildfires. But perhaps most importantly, acknowledging climate change and its impact on the ecosystems and our everyday lives would help us preserve a better future.