Extremely dry conditions and powerful Santa Ana winds have fueled over a week of devastating wildfires that are still burning in the Los Angeles area. The fires have been so widespread and hard to contain, and the freshwater supply so limited, that firefighters have resorted to skimming seawater off the Pacific Ocean to dump on the blazes as a last resort. Pat Megonigal, whose research explores the impact of saltwater on coastal environments, explains the effects saltwater can have on dry landscapes, and how studies show those effects vary over time and the landscape’s dryness.

Residents whose homes have survived the fires have other concerns to consider, including the safety of both the air inside their homes and their water supply. University of Colorado scientist Colleen Reid, who has studied the long-term effects when wildfire smoke invades homes, and Purdue University engineer Andrew Whelton, who has advised many community water departments after wildfires, explain the risks.

Thousands of others lost homes to the fires, and many more remain evacuated. They’re facing another challenge: finding affordable rental housing. As finance professor Anthony W. Orlando writes, the Los Angeles housing market is already one of the most expensive in the nation for buyers and renters and “is poorly equipped for this crisis.”

Meanwhile, investigators are looking at the likelihood human activities or equipment started the fires. University of Colorado scientist Virginia Iglesias writes about the role human construction and fast-moving fires play in increasing wildfire destruction in the U.S.

Also in this week’s science news:

• Legalized cannabis leads to less anti-anxiety medication
• Trees ‘remember’ wetter times – useful in changing climate
• Brain monitoring at work – what could go wrong?

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