Why 50 degrees feels frigid to some but warm to others: The science of acclimation

How well you tolerate temperatures is all about your body's ability to acclimate to the weather where you live

When Seth Darling, a meteorologist and producer at FOX Weather, moved to the Northeast after living in the South most of his life, he welcomed the break from the typically hot, humid weather to which he was accustomed.

"In the South, we would have multiple months in a row above 90 degrees and high humidity. It didn’t seem to bother me, because I was used to it," Darling said. "Now, when it is above 90 in New York for a day or two, if I’m not going to a pool or beach, I don’t go outside."

Samantha Thomas, who is also a meteorologist and producer at FOX Weather, had the opposite experience. She lived in New York for 24 years before making a full-circle trek west and south for eight years. She lived in places such as Wyoming, South Dakota, Texas and Georgia, before returning to New York.


"It was much easier for me to get used to a drier climate than to get used to living near the ocean again," Thomas said. "I’d take triple-digit highs and below-zero wind chills over New York humidity and damp-winter cold any day. I still feel like I haven’t gotten used to being back in the Northeast even though I grew up here."

How well people can tolerate hot vs. cold weather or muggy vs. dry weather all depends on how they acclimate to the environment in which they live. It’s something scientists have studied for years. Both soldiers and athletes use acclimation training to help them fight or compete in conditions that are foreign to them.

How acclimation works

When you move from one climate to another, there are a multitude of processes that happen in your body to help you deal with the changes in the environment. Those processes eventually help you become used to the weather in your new home – or acclimated.

François Haman, a professor at the University of Ottawa’s School of Human Kinetics, said acclimation is rooted in the amount of heat your body receives from the environment.

"So if I'm in warm conditions, I'm going to be gaining heat from the environment, and then my body's going to start sweating to be able to dissipate this, this heat," Haman said. "If I'm in a cold environment, I'm going to be doing the opposite. I'm going to vasoconstrict -- my blood flow will be reduced -- I'm going to vasoconstrict in order to retain that temperature at 37 degrees Celsius (98.6 degrees Fahrenheit)."

Sweating is another important part of the acclimation process. Haman said it is one of the best ways that our bodies regulate temperature. As the sweat evaporates, it takes heat from the body with it. Humid conditions make that process more difficult.


"If I go to dry conditions, generally, it's going to be easier to be able to face it because I'll be able to sweat very efficiently and be able to use that to evaporate," Haman said. "When I go into humid climates, then it's much tougher because … that sweat is going to accumulate but will not evaporate, meaning that you're going to have trouble regulating your temperature."

He said the body also uses a substance called "brown fat" to help regulate heat. 

"The brown fat, essentially, is full of mitochondria," Haman said. "The mitochondria is the powerhouse of the cells, and it can produce either energy … or it can produce heat."

Haman said whenever the body dips into its brown fat supply to regulate temperature, it uses its blood supply to circulate that heat throughout the body.

According to Haman, it takes a week or two for most people to become acclimated to their new normal. However, that is extremely dependent on how intense the changes are. He said a person’s body type and composition also play big parts in their ability to acclimate.

"So if you're smaller, you're way more vulnerable to cold, but you're better protected against heat stress," Haman said. "When you're much bigger, you're better protected against the cold, but you're actually more vulnerable to heat stress."

Can you help acclimation along?

Dr. Annamaria Macaluso Davidson, vice president of employee health medical operations at Memorial Hermann Hospital in Houston, said you can help your body get used to the new temperatures by slowly introducing yourself to them.

"It's a little bit like training for a marathon for athletes, in that kind of way you build up, over time, you build up your endurance and your ability to handle certain temperatures," Davidson said.


She said adequate hydration can help the process along.

"We use water to help break down stored energy that we have in our body, and you have to have water to do that," Davidson said. 

Dressing for the weather also goes a long way in getting you comfortable in your new climate, Davidson said. Focus on loose, breathable fabrics in hot weather and layers of clothing in cold weather.