Lenticular and Wave Clouds
As wind forces air over the top of mountains, it can force the formation of standing waves in the midst of that wind. As moist air rides up to the peak of the wave, it can condense in the cooler, higher atmosphere. These condensed peaks can stack on top of each other, and form lenticular clouds like we see in the top image above Mauna Kea. “Lenticular” comes from the Latin word for lens, describing the cloud’s oblong shape. Here’s a diagram of that windy wave, from Skybrary:
On the downwind side, those wave peaks can extend for miles and miles, forming spots of condensation at each peak along the way. This forms the beautiful wave clouds you see in the bottom image.
Clouds are pretty cool, eh?
Please read this.
(via The Atlantic Wire)
How the Sun and Moon Are Helping Sandy’s Waters Rise
As Hurricane Sandy makes landfall on the Northeast coast of the U.S. over the next couple days, we are already seeing reports of higher-than normal tidal surges for a storm this size. Hurricanes always bring high seas along with them thanks to their intense low pressure, but the fact that Hurricane Sandy happened during a full moon (Monday night) is putting that rising water on steroids.
In a full moon (or new moon), the Earth, Sun and Moon are aligned in a way that not only allows the usual lunar pull on the tides, but also a solar pull! It’s stretching the Earth’s oceans like taffy, creating more extreme high tides that will make Sandy’s surge much worse. The Moon has a much greater pull on tides because of its distance to Earth, but the Sun’s mass gives it a serious influence in situations like this.
The top image shows how this phenomenon works, with the radius of the Earth and Moon to scale. The thing that amazes me is how far apart, in size and in distance, these three bodies really are! The bottom image shows the correct size scale for the Sun, Moon and Earth, but only the Earth/Moon distance is to scale. The Sun would be so far away that I’d have to walk into the next office to finish the graphic!
Here’s a website you’ll want to keep an eye on for the next few days: Visualizing America’s Wind Patterns.
I’ve always thought the live, animated wind maps there were beautiful, one of my favorite science visualizations. But Sandy’s swirling, massive footprint of stormy chaos (in that map view I just captured) is turning the whole eastern half of the country into “Starry Night”!
Hurricane Sandy’s northward track over the past few days (top middle of your screen), animated from images captured by NASA’s GOES-13 satellite.
Stay safe, Northeastern friends. Earth’s just working out some aggression because of how stressed out all this climate business has her. We’ll see ya on the other side, and we’ll try to make it up to her.
So, what are your plans to stay occupied during the storm?
Hurricane Sandy as captured by the International Space Station crew earlier today.
We need to get George Clooney and Mark Wahlberg to the safety bunker, stat.
A Beautiful Chill
One of the most fascinating things about living in central Texas, where I live, is the volatility of the weather. And by “fascinating”, here I mean “completely weird and rather shocking.” This is my favorite part of the year in that regard. What we miss out on in terms of leaves changing color (they don’t) and a lowly hanging autumn sun (it’s high and hot until November), we make up for in pure meteorological chaos.
Tonight, the temperature will drop approximately 40 degrees Fahrenheit in three hours. It boggles my mind that this nothing but a huge bubble of cold air, swooping in clear from the reaches of the Arctic Circle all the way down to Texas. The rotation of the Earth and the jet stream grab hold of this icy mass of atmosphere like an invisible snowball, and throw it at 60 kilometers per hour in the direction of unsuspecting Texans, who today were sweating in shorts for the last time in 2012.
Although this year’s Blue Norther will arrive under cover of darkness, the pewter-colored wall of clouds that proceeds them is not a sight you’ll ever forget. We won’t quite reach freezing temperatures by morning, not like the record 65 degree drop seen in the 1911 Blue Norther, so the only frozen spiderwebs I’ll be seeing are right here on my computer screen. I think that’s fine with me. It’s always best to ease into this kind of chill if you ask me.
So as we in the northern half of the planet begin our descent into autumn chill, curl up with this beautiful science/art video gallery of exotic ice crystals forming on the tip of a needle. It’ll send chills up your spine.