As I post this, the National Unwatering Swat Team should be reaching New York City, where it will do what the National Unwatering Swat Team does best — remove water from places it shouldn't ever be. This is a different mandate than dewatering, in which water is removed from places where it's sometimes okay to have water. (Via Philip Bump) Read the rest
It can be a nice breeze, or a destructive storm, but either way wind is just moving air. And moving air is just moving molecules.
In an explainer for kids that's actually pretty helpful for grown-ups, too, Matt Shipman reminds us that the air around us isn't totally weightless. It weighs something, because molecules all weigh something:
They don't weigh very much (you couldn't put one on your bathroom scale), but their weight adds up, because there are a LOT of molecules in the air that makes up our atmosphere. All of that air is actually pretty heavy, so the air at the bottom of the atmosphere (like the air just above the ground) is getting pressed on by all of the air above it. That pressure pushes the air molecules at the bottom of the atmosphere a lot closer together than the air molecules at the top of the atmosphere.
And, because the air at the top of the atmosphere is pushing down on the air at the bottom of the atmosphere, the air molecules at the bottom REALLY want to spread out. So if there is an area where the air molecules are under high pressure (with a lot of weight pushing down), the air will spread out into areas that are under lower pressure (with less weight pushing down).
Read the full story at Carolina Parent
Image: wind, katarinahissen, a Creative Commons Attribution Share-Alike (2.0) image from mararie's photostream
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I'm sure you've all been very concerned, worrying about the impact Hurricane Sandy had on New York City's rat population. The good news: Rats can swim and, while many rats likely died during the storm, there are probably still plenty of them alive. The really interesting news: Nobody actually knows how many rats live in New York City. There could be as many as 32 million. Read the rest
The images above — prepared by NASA hurricane researcher Owen Kelly — were taken on Sunday, before Hurricane Sandy made landfall on the United States' Northeast coast. They're made from radar data collected by the Tropical Rainfall Measuring Mission (TRMM) satellite, and they show a feature of this storm that helps explain why it's caused much more destruction than you might expect from a Category 1 hurricane.
In the right-hand image, showing a close-up of the storm's eye, you can see a feature labeled "eyewall". Those are vertical cloud walls that surround the eye, and they're the spot with the strongest winds in the whole storm.
Placed in context, the TRMM-observed properties of Hurricane Sandy’s eyewall are evidence of remarkable vigor. Most hurricanes only have well-formed and compact eyewalls at category 3 strength or higher. Sandy was not only barely a category 1 hurricane, but Sandy was also experiencing strong wind shear, Sandy was going over ocean typically too cold to form hurricanes, and Sandy had been limping along as a marginal hurricane for several days.
That eyewall, says NASA and New Scientist, is the result of Sandy's Frankenstorm nature. Despite all the factors that should have made this storm weak, it represented the merging of several storm systems. Because of that, Sandy was stronger than a Category 1 storm normally is.
Read the full story on this at NASA and New Scientist
Via Michael Marshall
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Sixty milliseconds is fast. But sometimes, it's not fast enough. That's the gist of a great explainer by Cassie Rodenberg at Popular Mechanics, which answers the question, "Why do transformers explode?"
Before I link you over there, I want to add a quick reminder of what transformers actually are.
Although giant robots that turn into trucks do also explode from time to time, in this case we are talking about those cylindrical boxes that you see attached to electric poles. (Pesco posted a video of one exploding last night.) To understand what they do, you have to know the basics of the electric grid.
I find that it's easiest to picture the grid like a lazy river at a water park. That's because we aren't just talking about a bunch of wires, here. The grid is a circuit, just like the lazy river. Electricity has to flow along it from the power plant, to the customers, and back around to the power plant again. And, like a lazy river, the grid has to operate within certain limits. The electricity has to move at a constant speed (analogous to what engineers call frequency) and at a constant depth (analogous to voltage). This is where transformers come in. Read the rest
There are two answers here: One for the legitimately curious, and one for people who want a disaster to be a referendum on climate change.
Hurricane Hackers is a hashtag on Twitter (i.e., #hurricanehackers) and a crowdsource hub to create tech and social projects related to Hurricane Sandy. Proposed projects include an ad-hoc food and water delivery system for after the storm and live maps that show which businesses in a given area are actually open. You can propose projects or start working on projects other people have proposed. Check out the official Google Doc, or the IRC channel. (Via Shasha Costanza-Chock) Read the rest
If you're staying home from work today because of Hurricane Sandy, you might be able to help out a team of scientists from the University of Utah and Purdue. They're studying isotopes of water — small differences at the subatomic level that can tell you a lot about where water originally came from and how it got to the place it fell in the form of rain or snow. They need people collecting precipitation samples over 12-hour periods. And they're especially looking for help in some inland places, including West Virginia, Virginia, and eastern Kentucky/Tennesee. Find out more at their website. (Via Sarah Horst) Read the rest