There are many reasons why effective and immediate actions to reduce greenhouse gas emissions are needed, ranging from the melting of the Arctic sea-ice and of permafrost to the acidification of oceans and the loss of coral reefs. Another worrisome observation is an increase in fire frequency and intensity. Such an increase will speed up further increases in global temperature through positive feedback loops.
Increasing temperatures and decreasing rainfall, both caused by anthropogenic global climate change, increase drought in many regions of the world, especially in some regions of Africa, southeastern Australia, southern Europe, and the western United States. Such conditions are ideal for wildfires. In Europe, Greece has been the country hardest hit by fire. Just recently, huge wildfires devastated large areas in Australia. And Currently, there are yet again large wildfires devastating large areas in California.
The problem of fire is not that ecosystems are being burned. Occasional fires are a natural and important process in natural systems. Some ecosystems even require fire for their survival. For example, some species of pine in North-America require fire to release the seeds from their cones. However, the frequency and intensity of recent fires does pose problems even to fire-adapted ecosystems.
But the most worrisome problem is that fire releases large amounts of CO2 into the atmosphere. The more our climate is changing towards warmer and drier conditions, the more frequent and intense fires will occur, the more CO2 will be released into the atmosphere, the warmer it will get…such a positive feedback loop will contribute to faster warming than expected.
Especially worrisome is the increase in fire frequency in northern latitudes, such as in the Arctic tundra. Because fire burns organic layers on the ground, the soil is less well insulated to the above-ground temperature so that permafrost soil is melting faster than in unburned areas. In fact, researchers found that permafrost has “thawed to a depth of 40 cm in severely burned areas, compared with 18 cm in unburned sites.” (Nature, September 2009). Such melting will speed up yet another feedback loop, as described in a previous article.
It seems we really have enough reasons to act! And, as you can read on our portal, there are many courageous and inventive people around to make the changes we so urgently needt move us towards a carbon neutral society. Thank you for being or becoming one of them!