Rachel Nuwer | Smithsonian, June 2013

wealth of studies have examined the hypothesis that spending time outdoors boosts our well-being, but until now not much was known about how being outside affects what researchers call “momentary subjective well-being,” a fancy term for how you feel in-the-moment. Unless scientists follow participants around with a clip board asking them “How do you feel?” every few minutes, collecting such fleeting data remains a challenge.

A new study on happiness conducted in the UK gets over this obstacle by using a specially-designed smartphone app. More than 20,000 people installed the app on their phone. At random intervals throughout the day, the app would pop up and ask them brief questions about what they were up to, who they were with and how they were feeling. At the same time, it registered the phone owner’s GPS coordinates.

All told, the team collected around 1 million datapoints from the app-wielding participants. The results were telling: even when the authors controlled for factors like weather, time of day, where people were, if they were with friends or family and what they were doing, being outside trumped all of that for predicting in-the-moment happiness. On average, they found, the participants were significantly and substantially happier when they were outside surrounded by green or in a natural habitat. This finding was especially true when compared with their happiness levels while in an urban environment.

The authors conclude, “This study provides a new line of evidence on links between nature and wellbeing, strengthening existing evidence of a positive relationship between and exposure to green or natural environments in daily life.”

So if you’re feeling down or unenthusiastic, head outside for a few minutes and soak up the sunshine in a local park or backyard. It might just provide the positive boost you need to turn your day around – or at least bring some emotional warmth for a fleeting moment.