Why Your Car Dashboard Says It's a Lot Hotter Than It Really Is

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iStock

When you first turn on your car in the middle of a sunny day, chances are your dashboard probably says it’s quite hot out. Like, a lot hotter than it feels. There’s a reason why car thermometers don’t always seem accurate, according to atmospheric scientist Greg Porter at The Washington Post.

Your dashboard temperature reading actually comes from something called a thermistor, which is similar to a thermometer but instead of mercury, it uses electrical current to measure changes in temperature. (Remember that temperature is an indication of how fast or slow gas molecules in the air are moving around. The higher the reading, the greater the molecules' kinetic energy.) In a car, that thermistor is located just behind the grill in the front of the car. Therein lies the problem: Your car's temperature readings come from an unusually hot location.

Asphalt roads get really, really hot in warm weather (enough so that cities become significantly hotter than their greener surroundings in the summer), so a temperature reading taken just above the surface of the road isn’t going to be super accurate. Heat radiates up from the road—as you can see on particularly hot days when the highway starts to look shimmery—and the thermistor in your car picks up that excess heat. It’s like measuring the temperature of a large room by sticking the thermometer an inch away from the fireplace.

That doesn’t mean your dashboard temperature readings are useless. When it’s not as hot out, there isn’t much interference from heat rising off the road. It’s also more effective when you’re moving—if you’re traveling down the highway, it will pick up less heat radiation from the road than if you were sitting in a parked car. However, Porter warns, the thermistor isn’t sensitive enough to distinguish between one-degree differences, which can be dangerous if you’re driving in the winter and need to know if temperatures have hit freezing or are floating just above.

In short, as nice as it is to know how temperatures are changing from one destination on your road trip to another, take that dashboard number with a grain of (road) salt.

[h/t The Washington Post]

A Simple Trick for Defrosting Your Windshield in Less Than 60 Seconds

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iStock

As beautiful as a winter snowfall can be, the white stuff is certainly not without its irritations—especially if you have to get into your car and go somewhere. As if shoveling a path to the driver’s door wasn’t enough, then you’ve got a frozen windshield with which to contend. Everyone has his or her own tricks for warming up a car in record time—including appropriately-named meteorologist Ken Weathers, who works at WATE in Knoxville, Tennessee.

A while back, Weathers shared a homemade trick for defrosting your windshield in less than 60 seconds: spray the glass with a simple solution of one part water and two parts rubbing alcohol. “The reason why this works,” according to Weathers, “is [that] rubbing alcohol has a freezing point of 128 degrees below freezing.”

Watch the spray in action below.

[h/t: Travel + Leisure]

Website Lets You Report Individuals Affected by Hurricane Michael to Search-and-Rescue Teams

Brendan Smialowski, AFP/Getty Images
Brendan Smialowski, AFP/Getty Images

When Hurricane Michael made landfall in Florida as a Category 4 hurricane on October 10, it became the strongest storm to hit the continental U.S. since 1992. Homes from Florida to Virginia have since been leveled and at least 11 people have died. With internet and phone lines down across the disaster zone, many people are desperate to know if their loved ones are safe—now there's an online tool that can help them.

If you're having trouble getting in touch with someone who was in the hurricane's path, you can report them through a new website set up by the Florida National Guard, First Coast News reports. The site asks for the person's name, gender, age, and address, as well as any life-threatening issues they may be facing, such as low oxygen or medication supplies. After you submit their information, the State Emergency Operations Center forwards it to the relevant local agency doing recovery work.

Michael moved back over the Atlantic as a post-tropical storm Friday morning following its rampage through the southeastern U.S. More than 1000 search-and-rescue workers have already been deployed in Florida alone, and the death toll is expected to rise as clean-up efforts continue across the region.

[h/t First Coast News]

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