Scientists have found that generally the world feels brighter when you wake up.

People start the day in the best frame of mind in the morning, but end in the worst, at about midnight, the findings suggest, with the day of the week and the season also playing a part.

Mental health also tends to be more varied at weekends but steadier during the week, according to the study led by University College London.

“Generally, things do seem better in the morning,” the researchers concluded.

Mental health and wellbeing are dynamic in nature, and subject to change over short and long periods. However, few studies have looked at how they might change over the course of the day.

Scientists wanted to explore whether time of day was associated with variations in mental health, happiness, life satisfaction, sense of life being worthwhile and loneliness.

People in the study answered questionnaires, with questions such as: “In the past week, how happy did you feel?”, “How satisfied have you been with your life?”, and “To what extent have you felt the things you are doing in your life are worthwhile?”

Factors such as age, health conditions and whether people worked were taken into account.

The results showed that happiness, life satisfaction, and worthwhile ratings were all higher on Mondays and Fridays than on Sundays, while happiness was also higher on Tuesdays. There was no evidence that loneliness differed across days of the week.

There was clear evidence of a seasonal influence on mood. Compared with winter, people tended to have lower levels of depressive and anxiety symptoms and loneliness, and higher levels of happiness, and feeling that life was worthwhile in the three other seasons.

Mental health was best in the summer across all outcomes. But the season didn’t affect the associations observed across the day, however.

This was an observational study, so it cannot establish cause.

The Guardian.com. February 5, 2025. Adaptado.

Rain Is Coming to Burning Los Angeles and Will Bring Its Own Risks

Rain is forecast to begin as soon as Saturday afternoon and to continue as late as Monday evening, says meteorologist Kristan Lund of the National Weather Service’s Los Angeles office. The area desperately needs the precipitation, but experts are warily monitoring the situation because rain poses its own risks in recently burned areas— most notably the potential occurrence of mudslides and similar hazards. “Rain is good because we’ve been so dry,” Lund says. “However, if we get heavier rain rates or we get the thunderstorms, it’s actually a lot more dangerous because you can get debris flows.”

Fires do a couple of different things to the landscape that can increase the risk of burned material, soil and detritus hurtling out of control. When fires burn hot or long enough, they leave an invisible layer of waxy material just under the surface of the ground. This develops from decomposing leaves and other organic material, which contain naturally hydrophobic or water-repellent compounds. Fire can vaporize this litter, and the resulting gas seeps into the upper soil—where it quickly cools and condenses, forming the slippery layer.

When rain falls on ground that has been affected by this phenomenon, it can’t sink beyond the hydrophobic layer— so the water flows away, often hauling debris with it. “All of the trees, branches, everything that’s been burned—unfortunately, if it rains, that stuff just floats,” Lund says. “It’s really concerning.” Even a fire that isn’t severe enough to create a hydrophobic layer can still cause debris flows, says Danielle Touma, a climate scientist at the University of Texas at Austin. Under normal conditions, trees and other plants usually trap some rain above the surface, slowing the water’s downward journey. But on freshly burned land there’s much less greenery to interfere; all the rain immediately hits the ground. [...]

Fortunately, the rain should also help firefighters tame the blazes that remain active. The largest, the Palisades Fire, is currently 77 percent contained. The second largest, the Eaton Fire, is 95 percent contained. The Hughes Fire is third largest and only 56 percent contained. A fire can be fully contained but still burning. The containment percentage refers to the amount of the perimeter that has barriers that firefighters expect will prevent further spread.

Scientific American. January 27th, 2025. Adaptado.