资源环境科技发展态势分析平台

By Gege Li

Photographer
Josh Edelson  AFP/Getty Images

THIS is what a US wildfire looks like up close. Trees and embers burn on the other side of the Bidwell Bar Bridge, which spans California’s Lake Oroville in Butte county. These appear white in the image, while the lights to the right are from a small boat.

Thick smoke from the fire is responsible for the red hues. Smoke particles filter out shorter wavelengths of light, such as blue and yellow, while allowing longer, redder wavelengths through.

Its peculiar beauty is a dire warning about the power and spread of wildfires in the region. The Bear Fire in Butte County is part of a major crisis in the western US, where the most severe wildfires in two decades are destroying homes, landscapes and livelihoods.

The first wildfires started in California and Colorado in August. So far, more than 10 states have been affected, including Washington and Oregon. Collectively, some 18,000 square kilometres have been scorched.

The smoke could also have serious effects on health. The risk of lung infections from inhaling the smoke is made worse by the other pressing threat, covid-19.

Wildfires serve as a stark reminder of climate change. Longer and drier summer seasons coupled with strong winds are largely to blame for the unprecedented size and scale of the fires.