On a 72-degree day, they found that car interiors reached 91 degrees within 10 minutes. At 85 degrees outside, temperatures in the cars rose to 104 degrees within 10 minutes and to 119 within 30 minutes. At 95 degrees, temperatures rose to 119 within 15 minutes, peaking at over 140 within an hour. The darker the car’s interior, the hotter it became. Further, cracking the windows 1.5 to two inches was ineffective in reducing inside temperatures.
“The sun’s shortwave energy [also] heats any objects that it strikes [inside the car] such as the dashboard, which can heat to 180 to 200 degrees, steering wheel, child seat and animal carrier,” says Null. “These act as conductors to heat the adjacent air, followed by the effects of convection and long-wave radiation, which is very efficient at warming the air trapped inside a vehicle.”
If you’re traveling with pets in the summer, experts say you should take several steps to protect them:
l Turn on the air conditioner to cool the interior of vehicle on warm days for 10 minutes before placing animals inside. Check that the back seat, where your pet will travel, is sufficiently cool.
l Park in the shade during stops and remain with the animal.
l If you’re going on a long trip and will need food breaks, limit stops to drive-through restaurants when possible or eat at a place that will allow you to sit at a shady table outside with your pet.
l Never leave animals unattended in the car in warm weather.
l Give them plenty of water breaks.
l Car air conditioning can shut off, so don’t assume that leaving your pet in the car with the air conditioner running will be okay.
Use see-through sun shades on the back and side windows to shield animals from the sun.
Cool the animal immediately with flowing water if it exhibits any heat-related symptoms, and seek immediate veterinary attention if the symptoms worsen.
— Barbara Elisse Najar