As the weather gets increasingly colder, you may notice a sheen layer of frost coating the grass every morning. But what’s the science behind the winter-weather phenomenon? Let’s find out!
What exactly is frost?
Frost is actually just water vapor in the air that has deposited itself as ice onto a surface—usually something close to the ground, such as grass. Water exists in three states: solid, liquid, and gas. Frost is the effect of water turning from a gas (water vapor) into a solid (ice).
You’re probably familiar with the layer of dew that sometimes coats grass. Well, frost is just frozen dew!
How does it form?
Frost only forms on a surface when the temperature is below freezing, 32 degrees Fahrenheit. A blade of grass actually loses energy by emitting a non-lethal form of radiation. After losing this energy, it absorbs energy from surrounding objects to replenish. When a blade of grass loses more energy than it gains, it becomes cold enough for the water vapor to cling on and form frost.
Why do I only see it in the morning?
Not only does the temperature obviously drop overnight, but the lack of sunlight is actually what causes the grass to lose more energy than it gains. This sets off the process described above to create the frost that you see from your window in the early morning hours.
What are the effects?
While a light frost can look cool, it is actually quite harmful to grass. A blade of grass needs to keep the water moving through to the roots to stay alive and healthy. The frost freezes the water inside the blade, halting the process and causing damage to the cell walls. After several frosty mornings, the lawn may begin to show damage through yellow or brown patches and could eventually die.
Luckily, you can take steps to protect your lawn from frost. Refrain from stepping on the frosty grass, try to mow the lawn later in the day when the temperature rises, and remove any unnecessary items from the yard that may cause shady areas.
Essentially, that morning frost is the result of the perfect mixture of cold temperatures and energy transference. Next time you see a frosty morning, you’ll now know the science behind the scene!