UCLA Spinlab has another great video demonstrating the effects of rotation on a fluid. In a non-rotating fluid, flow over an obstacle is typically three-dimensional, with flow moving over as well as around the object. But in a steadily rotating fluid, as shown in the latter half of the video, the flow only moves around the obstacle, not over it. This non-intuitive behavior is part of the Taylor-Proudman theorem, which shows that flow around an obstacle in a rapidly rotating fluid will be two-dimensional and confined to planes perpendicular to the axis of rotation. (For the mathematically-inclined, Wikipedia does have a short derivation.) This 2D flow creates what are called Taylor columns over the obstacle. The Taylor column is like an imaginary extension of the original obstacle, turning the puck into a tall cylinder, and it’s real enough to flow, which diverts around it as though the column were there. (Video credit: UCLA Spinlab)
Anyone who has spent much time in an urban environment is familiar with the gusty turbulence that can be generated by steady winds interacting with tall buildings. To the atmospheric boundary layer—the first few hundred meters of atmosphere just above the ground—cities, forests, and other terrain changes act like sudden patches of roughness that disturb the flow and generate turbulence. The video above shows a numerical simulation of flow over an urban environment. The incoming flow off the ocean is relatively calm due to the smoothness of the water. But the roughness of an artificial island just off the coast acts like a trip, creating a new and more turbulent boundary layer within the atmospheric boundary layer. It’s this growing internal boundary layer whose turbulence we see visualized in greens and reds. (Video credit: H. Knoop et al.)
Saturday morning Japan’s Mount Ontake erupted unexpectedly, sending a pyroclastic flow streaming down the mountain. Many, though sadly not all, of the volcano’s hikers and visitors survived the eruption. Pyroclastic flows are fast-moving turbulent and often super-heated clouds filled with ash and poisonous gases. They can reach speeds of 700 kph and temperatures of 1000 degrees C. The usual gases released in a pyroclastic flow are denser than air, causing the cloud to remain near the ground. This is problematic for those trying to escape because the poisonous gases can fill the same low-lying areas in which survivors shelter. Heavy ashfall from the flow can destroy buildings or cause mudslides, and the fine volcanic glass particles in the ash are dangerous to inhale. The sheer power and scale of these geophysical flows is stunning to behold. Those who have witnessed it firsthand and survived are incredibly fortunate. For more on the science and history of Mount Ontake, see this detailed write-up at io9. (Image credits: A. Shimbun, source video; K. Terutoshi, source video; via io9)
One of the great wonders of life is watching the leaves change colors in the fall. When temperatures get cool, chlorophyll begins to break down revealing the underlying pigments in the plants’ sap. This depiction of the inner-workings of a maple leaf shows the process in action.
Outer space or under water? We partner with the Monterey Bay Aquarium Research Institute on “blue-water” dives in Monterey Bay, and our jellies aquarist Wyatt Patry recently observed a bloom of salps (jelly relatives).
One month to lift off, folks. So, let’s have some fun of the BEWARE THE WILD variety.
And since it’s not a party until someone says nice things about my debut novel, allow me to kick things off right with a trifecta:
“A lovely modern fairy tale as tangled and dark as the swamp it lurks in. Parker’s debut is American myth at its very best!” —Kiersten White, NYT bestselling author
“Parker has a nice touch with the Southern flavor of Sterling’s Louisiana town, steeped in superstition and silence…This engaging debut should enjoy a wide audience.” —Kirkus Reviews
“A creepy, atmospheric book that will draw readers in…Beware the Wild breathes new life into the teen supernatural genre.” —School Library Journal
Now, it’s a party. And I’ve made all sorts of goodies for you, including the GIFs above. I’m giving away bookmarks for marking books, book plates (of which there are two designs and you must pick only one, Highlander style), magnets for magging nets, and I <3 YA Books bumper stickers. All are absolutely free with your pre-order of BEWARE THE WILD.
This post is going to be long enough as is, so let’s get right to it. I’m celebrating in two ways:
Submit proof of purchase (email, scan, photo, etc. of your receipt) at firstname.lastname@example.org, along with a valid mailing address.
On October 21st, 2014, you will be mailed a signed bookmark, your choice of a cherry blossom or gator head bookplate, a fancy schmancy magnet, and an I <3 YA Books bumper sticker. (NOTE: These bumperstickers will accompany me on the Roadside YA Tour in late October. The only ways to acquire these is to pre-order now or attend a tour event later).
Submissions for the giveaway close October 20th, 2014 at 11:59pm PST.
Now, because BEWARE THE WILD and BLUE LILY, LILY BLUE come out on the very same day and because one day long ago Maggie said to me, “Parker, stop whinging and write something good,” it’s cosmically significant that I find myself in possession of one of the oh-so-rare ARCs of BLLB. To keep myself good with the cosmos, I’m passing this good fortune on to one of you.
In addition, I’m giving away a small bundle of some of my favorite collections of words. They are: THE PARABLE OF THE SOWER by Octavia Butler, SAVING FRANCESCA by Melina Marchetta, THE BOOK OF THREE by Lloyd Alexander, and THE DARK IS RISING by Susan Cooper.
One winner will get all 5 books.
2. BOOK PRIZE:
Reblog this post and you will be automatically entered to win the stack of my favorite books along with the ARC of Maggie Stiefvater’s BLUE LILY, LILY BLUE. Only one reblog per person will be counted!
Tweet some version of “Pre-order BEWARE THE WILD! Enter to win an ARC of BLUE LILIY, LILY BLUE! *include a link to this post here* #bewarethewild” for a bonus second entry. NOTE: Please use the hashtag so I can find it!
For all the usual reasons, this contest is only open to those with a valid North American mailing address. (I wish it wasn’t so!)
Submissions for the contest close September 30th, 2014 at 11:59pm PST.
Just to be absolutely, 100%, no bones about it clear: no pre-order is necessary to enter this contest.