This blog provides commentary on interesting geological events occurring around the world in the context of my own work. This work is, broadly, geological fluid dynamics. The events that I highlight here are those that resonate with my professional life and ideas, and my goal is to interpret them in the context of ideas I've developed in my research. The blog does not represent any particular research agenda. It is written on a personal basis and does not seek to represent the University of Illinois, where I am a professor of geology and physics. Enjoy Geology in Motion! I would be glad to be alerted to geologic events of interest to post here! I hope that this blog can provide current event materials that will make geology come alive.

Banner image is by Ludie Cochrane..

Susan Kieffer can be contacted at s1kieffer at gmail.com

Thursday, November 7, 2013

How does Super Typhoon Haiyan ("Yolanda") compare with Jupiter's Great Red Spot?

Updated: November 8, 2013

Super Typhoon Haiyan is now being called one of the largest storms ever. For a nice display of images of 13 of the largest storms, see here. Other posts on this blog related to this are: Super Typhoon Usagi in the Philippines just six weeks ago, including a Table of the Categories of hurricane (cyclone) strength; Tropical Storm Phailin and Thailand; and Cyclone Tracy and the Bill and Boyd song "Santa Never Made it to Darwin" (because Cyclone Tracy struck on Christmas Eve and Day, 1974).

Here is a link to Dave Petley's Landslide Blog that has a post today on the landslide potential due to the storm.

End of upate______________________________________
Super Typhoon Haiyan, November 7, 2013, 21:30 UTC
NOAA image
Super Typhoon Haiyan is headed toward the Philippines, due for landfall Friday morning (here's the CNN.com report on it). At the moment its winds of 195 mph with gusts up to 230 mph make it a Category 5 on the hurricane scale [Note: Weather.com put the winds somewhat lower--sustained at 134 mph and gusts to 155 mph]. (For comparison, we had a fairly major wind storm on Whidbey Island a week ago with winds up to 40-60 mph! Took down a lot of tree branches and some trees, caused power outages not only here but on the mainland for 8+ hours. Quite humbling to think of what it's going to be like in the Philippines.) This is the largest storm to date this year; its diameter is about 800 km (500 miles). For comparison with Yolanda, the most intense sustained winds appear to have been in about 190 mph in several typhoons (Typoons Tip, Grace, Vera, Sarah in the Pacific, and Hurricanes Allen and Camille in the Atlantic), so Yolanda is on-course to be close to a record-setter. More than 3800 people have been moved to evacuation centers, most from the central region of the Philippines. As shown on the adjacent map, the typhoon is projected to cross the South China Sea (to the west of the Philippines) and then hit Vietnam and Cambodia. It's speed has been 20-24 mph.
Path of Super Typhoon Yolanda
     The winds and rain from the storm are one thing, but there are other dangers. The island of Bohol in its path was hit by a magnitude 7.1 earthquake just a month ago. 350,000 people were displaced by that quake and are extremely vulnerable. Last December, Super Typhoon Bopha hit the southern Philippines, killing over 1000 people and affecting six million. A quarter million homes were damaged or destroyed. Landslides during storms in the Philippines are a constant danger.
Jupiter Great Red Spot NASA image
In the high resolution version of this image, objects as
small as 600 km (~400 miles) can be seen. Thus
Super Typhoon Haiyan, with a diameter of 500 miles--
would be a tiny dot just barely visible.
     According to the International Business Times, a Philippines government website specifically dedicated to disaster reduction was hacked just as the typhoon approached and, as of yesterday, was still not accessible. The website was supposed to provide Filipinos with real-time information about threats such as cyclones, tsunami, floods, landslides and fires, as well as providing general safety advice on preparation and surviving disasters.
     How do our earth storms compare to the Great Red Spot on Jupiter? This storm was first observed by Cassini in the late 1600's, and scientists believe that it is actually older than that. This is an anticyclonic storm (rotates anticlockwise) with a period of about six Earth days (14 Jupiter days). It's 24,000-40,000 km in EW direction, and 12,000-14,000 NS. It is large enough to contain 2-3 Earth's, so even our biggest storms don't compete! Winds around the edge of the spot reach 432 km/hour (268 mph).
    See the Figure caption to compare Super Typhoon Haiyan with the Great Red Spot!

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