Summer scents have the power to transport us back to our fondest sun-soaked memories. Even in the dreary cold of winter, one whiff of an ocean-scented candle can fill your mind with images of long summer days spent lounging by the sea. That’s because of the unique way that your brain processes smells. When a fragrance fills your nose, the scent information reaches some parts of your brain more quickly than others. At first, it bypasses most parts of the brain associated with conscious thought, taking a direct route to the areas that control social reflexes, emotional rewards, sexual behavior, and memory. Because the brain processes scents this way, they can trigger an emotional reaction or rush of memories before you’ve even fully processed what you’re smelling.
Most of us have positive memories we associate with summer—being off school, playing outside, going on vacation, and feeling endlessly drawn towards large bodies of water in an attempt to beat the heat. Here, we break down the science behind some of the most classic summer scents to answer the question: What does summer smell like?
Summer smells like… the beach.
Where warm sand meets the cool ocean water, you’ll find one of nature’s most complex scentscapes. On the surface, the salty seaside air seems to have a pretty self-explanatory scent—it is next to a large body of salt water, after all. However, salt and water are both scentless. The smell we associate with the beach actually comes from a few different sources, both organic and inorganic. These include:
- Bromophenols: These naturally occurring substances result from reactions between bromide, iodine, and phenols in seawater. Bromophenols have a strong fish-like scent that we associate with crustaceans and algae. In high concentrations, they can also create medicine-like tastes and odors, thanks to the iodine in the compound.
- Ectocarpene: If you ever notice a strange, strong fruity smell at the beach, it may be due to this pheromone. Algae in the ocean use ectocarpene to communicate with each other and attract mates.
- Dictyopterenes: Another class of pheromones, dictyopterenes are made by seaweed. You’re most likely to smell the strong “ocean smell” of dictyopterenes during low tide.
- Dimethyl sulfide: The pungent, sulfury smell of the seaside is created by bacteria activity. As bacteria break down and digest phytoplankton (microscopic algae that live in the ocean), they produce the odorous compound dimethyl sulfide.
- Putrescine and cadaverine: You can’t escape the circle of life, even at the beach. When dead fish, crabs, and other marine life start to decay, they produce putrescine and cadaverine. Sometimes, our noses register these nasty-smelling chemicals as sweet scents. Other times, they may remind you of the ocean. (Or, you may just find them disgusting.)
Summer smells like… the lake.
While lakes are less active than the bustling marine hubs of the shoreline, they’re still home to unique organisms and processes that create a very distinct scentscape. The most prominent of these is a natural phenomenon called “lake turnover,” which typically happens once during the spring and once during the fall.
During the summer, water in lakes tends to separate into distinct layers. This typically happens in lakes greater than 20 feet deep. Warm water sits on the top of the lake, while cooler, dense water sinks to the bottom. These layers stay pretty static during the heat of the summer, and there’s not much mixing of oxygen or organisms between the layers.
As the weather starts to cool, the temperature difference between the top and bottom layers decreases, and the lake water starts to mix—this is lake turnover. While this process allows oxygen and nutrients to be redistributed more evenly throughout the lake, it can also dredge up some not-so-pleasant odors.
When the lake is stagnant, dead plants and other organic matter can get trapped at the bottom of the lake. As they decompose, they release hydrogen sulfide gas into the water. When the lake turns over and the bottom layer of water rises to the top, the buildup of hydrogen sulfide gas finally reaches the surface to be released into the atmosphere. This causes a “rotten egg” smell that tends to be strongest in the late spring and fall.
What should you do when your water smells like sulfur?
If you live somewhere that gets tap water from a local lake or reservoir, you may notice a sulfur smell coming from your faucets around the time turnover occurs. Homes with groundwater sources, including wells, may also experience sulfur-smelling water from time to time. If you notice your tap water starting to take on that characteristic rotten egg smell, you may want to do a little troubleshooting to make sure the sulfur isn’t coming from within your plumbing system.
To figure this out, try running your cold water tap for a few minutes. If the smell sticks around, it’s probably coming from your water supply. You may be able to use a water filtration system to cut down on the smell. If the odor gets less noticeable over time, it may come from a problem in your plumbing system that requires further investigation.
Summer smells like… sunscreen.
Of course, you can’t—or shouldn’t—spend the day at the beach or lake without bringing along some sunscreen. Avobenzone is a common ingredient in most suntan lotions thanks to its ability to block UVA and UVB rays. It’s also what gives sunscreen its characteristic smell. While avobenzone is great at protecting your skin from harmful UV rays, it’s not your only option to ward off skin damage this summer. If the smell of traditional sunscreen bothers you, try looking for a lotion without this ingredient.
As of 2021, the FDA recognizes two sunscreen ingredients as totally safe: titanium dioxide and zinc oxide. Both are commonly used as active ingredients in sunscreens due to their ability to block UVA and UVB rays. Suntan lotion with either of these ingredients should help protect your skin from sun damage and protect your nose from the odor of avobenzone.
Summer smells like… a campfire.
Whether it’s roasting marshmallows, cooking hot dogs, or just sitting around chatting with the people you love, summer campfires are the center of many treasured (but smoke-scented) memories. Campfires are different from other wood fires because they often include scavenged twigs, branches, and leaves that burn less efficiently than dry, seasoned wood logs. That’s why campfires tend to be much smokier—and may contain more unhealthy byproducts—than fireplace fires.
The smoky smell of a campfire is created through combustion—a chemical reaction in which heat breaks down the molecules in wood to create smoke and ash. Two compounds in campfire smoke contribute to the scent we associate with fire: acrolein and phenols.
- Acrolein is a fast-evaporating liquid that can be released into the air when wood is burned. According to the CDC, exposure to acrolein can cause burning in the throat and nose and damage to the lungs.
- Phenols, or phenolic compounds, are also created during combustion, and they may be responsible for the smoky flavor we associate with grilled or smoked foods. Exposure to phenol can lead to skin, eye, nose, and throat irritation, as well as more severe health effects.
How can you get the campfire smell out of clothes?
After a night of sitting around a campfire with your friends or family, you may bring home more than just memories. The smoky smell that saturates your clothes is caused by physical substances in campfire smoke. So, to get rid of the odor, you have to physically remove the cause of the smell. Warm water and soap are usually great for breaking down and removing odor-causing substances from clothes and surfaces. And, if you need a little extra help scrubbing out the smell, a mixture of water and white vinegar or baking soda should have no problem breaking down the scent molecules clinging to your clothes.
Summer smells like… fresh fruit.
What’s more refreshing than biting into a piece of fresh fruit on a hot summer day? Raspberries, peaches, blueberries, cherries, and watermelon are all in season during the summer, and citrus drinks like lemonade and limeade are a staple of many barbecues and poolside gatherings. We gravitate towards tart, sweet fruits during the warmer months, so it’s no wonder that fruity scents are so closely linked to this season.
A few different types of chemical compounds give fresh fruit its mouthwatering aroma, and each fruit has dozens—or hundreds—of them. Most of these compounds fall into two categories: esters and aldehydes. These organic compounds tend to be volatile, meaning they evaporate quickly at room temperature. So, when you cut into a piece of fruit, these scent molecules quickly enter the air, filling your nostrils (and your kitchen) with a refreshing, fruity scent.
Savoring the scents of summer
The scentscapes you surround yourself with can become a potent part of the memories you make this summer. You may not realize it as it’s happening, but you’ll definitely notice when you stumble upon a scent that brings you right back to the fun times you had during the dog days of summer. While you’re living life and savoring the diverse bouquet of scents that summer has to offer, don’t forget to keep an eye on outdoor air quality. Wildfires, pollen, and other types of pollution don’t only impact the smells of summer—they can also affect your health. Learn more in our post on how air quality impacts exercise and other outdoor activities.
Header photo by Agung Pratama, dog and boy on beach photo by Jacub Gomez, friends on the lake photo by Ron Lach, boy applying sunscreen lotion photo by Kindel Media, campfire photo by Tomáš Malík, fresh fruit photo by Anna Tukhfatullina