If you think about it, summer is not the best time of year, and may even be the worst
Summer is commonly considered the best time of year: the beach, ice cream, long evenings outdoors, morning birdsong outside the window. But if you look at the facts, the picture is far less idyllic. From a scientific standpoint, summer is the most dangerous season, and it’s only getting worse each year. Here are five research-backed reasons that will make you see the hot months in a new light.
The Danger of Ticks and Mosquitoes in Summer
If there’s one thing most people agree on, it’s their dislike of mosquitoes and ticks. But it’s not just about the annoying bites — the summer activity of blood-sucking insects poses a serious health threat. Warm and humid weather accelerates their reproduction and metabolism, which means more frequent bites.
According to scientists, approximately 476,000 people in America are diagnosed with Lyme disease annually and undergo treatment, with most cases occurring in late spring and summer. West Nile virus, first detected in the U.S. only in 1999, has become the country’s most widespread mosquito-borne disease over the past quarter century, affecting thousands of people each year. Meanwhile, the incidence of anaplasmosis and Powassan encephalitis has more than doubled over the past twenty years.
Climate change is making this problem even more acute: summers are becoming longer, hotter, and in some regions, more humid. This means the season of disease-carrier activity is extending, and the risk of infection increases with each passing year.
Extreme Heat and Hurricanes
Deadly heat waves, destructive downpours, tornadoes, floods, hurricanes, wildfires — all of these occur most frequently in summer. The main reason is a warmer atmosphere that retains more energy and moisture. This fuels storm systems while simultaneously intensifying heat stress at the surface.
Summer heat waves are becoming increasingly frequent and intense against the backdrop of global warming. The combination of extreme heat and high humidity is one of the deadliest weather phenomena: it exacerbates chronic diseases and can lead to heat stroke. At the same time, high temperatures increase evaporation, leading to drought and a higher risk of wildfires. And smoke from fires further degrades air quality.
During this same period, tropical cyclones intensify: warm ocean water, favorable wind conditions, and a humid, unstable atmosphere create an ideal environment for hurricanes. The same factors contribute to the formation of powerful thunderstorms and tornadoes, especially in the central states of the U.S.
Electricity Bills in Summer
When it’s scorching outside, the air conditioner runs at full blast, and electricity bills become steep. Yes, utility bills aren’t as high as in winter during the heating season. But air conditioning still consumes enormous amounts of energy.
As global temperatures rise, coping with heat becomes increasingly difficult. People turn on their air conditioners more often and for longer periods. According to the International Energy Agency’s forecast, by 2050 global electricity demand for air conditioning will triple — equivalent to installing 10 new air conditioners every second for the coming decades.
It creates a vicious cycle: the hotter summers get, the more electricity we spend on cooling, the more greenhouse gases we emit, and the hotter the next summer becomes. For the average person, this means one thing: summer utility bills will only keep rising.
Ultraviolet Radiation and Skin Cancer
Few people enjoy having to apply sunscreen every time they step outside. But the risk of ultraviolet radiation genuinely increases dramatically in summer — and the statistics confirm it.
Over the past fifty years, the incidence of malignant melanoma — the most aggressive type of skin cancer — has risen sharply worldwide. In 2020, more than 325,000 new cases were recorded. Researchers link this growth to changes in ultraviolet radiation levels, which in turn are caused by shifts in atmospheric conditions: variability in cloud cover, aerosol concentrations, and the reflectivity of the Earth’s surface.
In other words, it’s not just that people sunbathe more. The atmosphere itself is changing in ways that allow more dangerous radiation through. And summer is the peak of UV activity, when solar rays hit at the most direct angle and spend the most time “in contact” with the skin.
A family applying sunscreen at the beach
Violence Increases in Summer
This point may seem unexpected, but research shows a statistically significant link between high temperatures and levels of violence. According to data from the Gun Violence Archive, over the past decade the highest number of mass shootings in the U.S. was recorded in June, July, and August, while the lowest was from December through March.
A systematic review and meta-analysis of 37 studies from 11 countries found that rising air temperatures are associated with increases in homicides, assaults, sexual crimes, gun violence, and domestic violence. Notably, temperature has no significant effect on non-violent crimes.
There may be several reasons for this. First, people spend more time outdoors in summer, attend events more often, and consume alcohol, creating more situations for conflict. Second, heat itself can increase stress and irritability levels: neurobiological research indicates that heat stress affects hormonal balance, particularly raising cortisol levels. Sleep disturbances caused by stuffiness further reduce self-control.
A scorching city street in the summer heat
Given that heat waves are becoming longer and more intense, scientists warn that this effect will likely only grow stronger.
None of the above means that summer should be canceled or spent in a bunker. But understanding the real risks — from ticks and ultraviolet radiation to extreme weather and rising aggression — helps you prepare for them. Summer can still be enjoyable, but each year it requires a bit more awareness: protecting yourself from the sun and insects, keeping an eye on the forecast, and not being surprised if your electricity bill breaks another record.
