Stories tagged heat
Flowerpots in full flame
Courtesy GatheringZeroIn my continuing quest to keep the public informed about exploding household objects, I bring you the case of the exploding......FLOWERPOT house fire?! I’m sorry but of all the things that could explode, a flowerpot falls pretty low on my list of potential hazards. The St. Paul Fire Department investigator, James Novak, agrees, “It’s not like everybody has to worry that their house is going to burn down...halogen lights, smoking, candles and Pop-Tarts in a toaster--there are a lot of things higher on the priority list than a potted plant fire.” Nevertheless, the combination of fertilizer, heat and oxygen within the pot can lead to potentially unorthodox flower pot behavior. Consider yourselves warned. As for me, I think a conversation with my fern about fire safety is long overdue.
Tags : 
White roofs reflect heat, leaving the structures below cooler: Photo by gadfly pro from Flickr.com
Looking for an easy way to reduce global warming, and save yourself a few bucks in the process? Paint your roof white! Most rooftops in America are black or some other dark color. These absorb heat, making the building hotter and less comfortable. People in the building run fans and air conditioners to cool off. Not only do they spend more on energy, but the power companies have to burn coal and oil to produce the electricity.
But a white roof reflects heat. The building stays cooler, and needs less electricity.
For maximum effect, you should use special heat-reflective materials. And keep the roof clean – dust and dirt darken the roof, reducing its reflective properties.
It’s been estimated that if every roof in the world were white, it would counteract all the global warming of the last 30 years! Now, the authors of this study admit that they used a very simple model – climate is much more complicated than their equations allow – but still, like changing your lightbulbs, this seems like an easy way to start having an impact now. In California, the government is giving rebates to building owners who install cool roofs.
Photo by gadfly pro from Flickr.com
Please contact us if you have questions about the rights on this image.
Stay warm out there
in Earth and Space Science, Life Science, The Water Cycle, Weather and Climate, and Human Organism
It's cold this morning. Maybe the coldest morning of the season so far? Luckily, there's also a lot of sunshine, and almost no wind.
If it were windy, you'd hear the weather forecasters talking a lot not only about the air temperature (-6 degrees when I left the house), but also about the "wind chill." Wind chill is a way to describe how quickly heat is transferred from your body to the atmosphere when it's both cold and windy outside. As wind increases, more heat is drawn from your body, decreasing your skin temperature and eventually your internal body temperature. Wind chill makes it feel much colder than it actually is.
Last year, I overheard a woman in the Science Museum parking garage elevator talking about how she parks her car in a sheltered area to protect it from wind chill. She was worried that, if she left it in a more exposed area, it wouldn't start. I can't say anything about the state of her car battery, or condensation on her distributor, but I can say that wind chill has very little impact on cars or any other inanimate objects: wind will shorten the time it takes for an object to cool to the temperature of the surrounding air, but it won't get any colder than that no matter how much wind there is.
For humans and animals, though, wind chill affects how quickly hypothermia and frostbite can occur. Hypothermia is a condition in which core body temperature has fallen to the point where normal muscle and brain functions are interrupted. (Thor did a post about hypothermia a few weeks ago.) Frostnip/frostbite are conditions in which body tissues freeze. Knowing the wind chill helps us make decisions to avoid these and other cold weather dangers.
She's got the right idea: Bundle up! (Photo by Yann Richie)
The best thing to do when there's a significant wind chill is to stay inside. But you can't stay at home on the sofa all winter. So what can you do? Dress right when you go outside. That means wearing several layers of loose-fitting, lightweight, warm clothing. (Trapped air between the layers will insulate you and keep you warm.) Stay dry. (Remove layers if need be to avoid sweating and later being wet and cold.) Wear a tightly woven, water repellent, hooded top layer. Cover your mouth to protect your lungs from the cold. Mittens, which allow your fingers to share warmth, are better than gloves. And your mom was right: wear a hat! Half your body heat can be lost from your head.
Science Buzz and all related activities
Add a new comment