Recent research suggests that summer really does tend to be a time of reduced productivity. Our brains do, figuratively, wilt.
One of the key issues is motivation: when the weather is unpleasant, no one wants to go outside, but when the sun is shining, the air is warm, and the sky is blue, leisure calls.
on rainy days, men spent, on average, thirty more minutes at work than they did on comparatively sunny days.
bad weather made workers more productive, as measured by the time it took them to complete assigned tasks in a loan-application process.
When the weather improved, in contrast, productivity fell. The mere thought of pleasant alternatives made people concentrate less.
In summer, our thinking itself may simply become lazier.
Pleasant weather can often lead to a disconcerting lapse in thoughtfulness.
The better the weather, the easier it was to get the students to buy into a less-than-solid argument: on days that were sunny, clear, and warm, people were equally persuaded by both strong and weak arguments in favor of end-of-year comprehensive exams.
When the weather was rainy, cloudy, and cold, their critical faculties improved: in that condition, only the strong argument was persuasive.
Summer weather—especially the muggy kind—may also reduce both our attention and our energy levels.
In one study, high humidity lowered concentration and increased sleepiness among participants.
The weather also hurt their ability to think critically: the hotter it got, the less likely they were to question what they were told.
The shift toward mindlessness may be rooted in our emotions.
People get happier as days get longer and warmer in the approach to the summer solstice, and less happy as days get colder and shorter.
They also report higher life satisfaction on relatively pleasant days. The happiest season, then, is summer.
A good mood, generally speaking, has in turn been linked to the same type of heuristic, relatively mindless thinking.
A bad mood tends to stimulate more rigorous analytical thought. Weather-related mood effects can thus play out in our real-life decisions—even weighty ones.
There’s a limit to heat’s ability to boost our mood.
when temperatures reach the kind of summer highs that mark heat waves all over the world, the effect rapidly deteriorates.
on days when the temperature rose above ninety degrees, the negative impact on happiness levels was greater than the consequences of being widowed or divorced.
Our cognitive abilities seem to improve up to a certain temperature, and then, as the temperature continues to rise, quickly diminish.
the optimal temperature hovered around seventy-two degrees Fahrenheit, twenty-seven degrees Celsius, or roughly eighty-one degrees Fahrenheit.
Blistering heat does give us a perfectly good reason to eat ice cream: studies have shown again and again that blood glucose levels are tied to cognitive performance and willpower. A bite of something frozen and sweet, boosting depleted glucose stores, might be just what a brain needs as the temperature spikes.