The huge undersea earthquake near Samoa produced not one but 4 tsunami waves shortly after the 8.0 earthquake struck. Video from Samoa and American Samoa shows the devastation shortly after the waves hit. Click here for details on the earthquake and the preliminary report. Initially it was reported a single wave of 5 feet struck American Samoa. Now, reports say that 4 waves of 15-20 feet high crashed through the islands and that the death toll is at least 119. Because of the extreme distance from the US mainland and even Hawaii, logistics make it difficult to get supplies and a full relief effort into motion.
Meanwhile, another earthquake struck near Sumatra, Indonesia this morning. Video from shortly after the quake shows the confusion and turmoil following the quake. The USGS data suggest a 7.6 magnitude earthquake struck at 10:16 UTC today and was centered pretty deep at nearly 50 miles below the surface. That would be at 6:16 am EDT. Here is the summary from the USGS.
The magnitude 7.6 southern Sumatra earthquake of September 30, 2009 occurred as a result of oblique-thrust faulting near the subduction interface plate boundary between the Australian and Sunda plates. At the location of this earthquake, the Australian Plate moves northeast with respect to the Sunda plate at a velocity of approximately 65 mm/yr.
On the basis of the currently available fault mechanism information and earthquake depth of 80 km, it is likely that this earthquake occurred within the subducting Australian Plate rather than on the plate interface itself. The recent earthquake was deeper than typical subduction thrust earthquakes that generally occur at depths less than 50 km.
The subduction zone surrounding the immediate region of this event has not witnessed a megathrust earthquake in the recent past, rupturing last in an earthquake of M 8.5 or larger in 1833. Approximately 350 km to the south, a 250 km section of the plate boundary slipped during an Mw 8.4 earthquake in September 2007, while approximately 300 km to the north, a 350 km section slipped during the Mw 8.7 earthquake of March 2005. In early 2008, the plate boundary updip of today’s earthquake was active in a sequence of Mw 5-6 earthquakes. It is not clear how today’s earthquake is related to the sequence of megathrust subduction zone events on the shallower section of the plate boundary.
This earthquake was near to the same area of a 9.1 magnitude quake in December 2004 that killed 232, 000 people following a devastating tsunami that affected coastal nations far away from the quake. The difference here is that 7.6 quake produces far less energy than a 9.1 quake and I believe that it was about 18 miles below the surface. So far, there have been no reports of a tsunami but 75 deaths have been reported from the Indonesian quake so far, but with the collapse of buildings and rescue efforts continuing, the number is sure to rise.
Whenever there is a natural disaster, there is often a fear for disease in the aftermath. Often, the disease following the event kills more people than the event itself. That may be a problem in the Philippines where at least one report came in describing a Philippine disaster center with one toilet for 3000 people. A report from Reuter’s regarding the post flooding disaster in the Philippines says there are ”hundreds of thousands of Filipinos displaced, survival is now a daily struggle in squalid, makeshift evacuation centres.”
Meanwhile, fears of another tropical cyclone are being raised, and justifiably so. First off, Tropical Storm Parma is expected to become a Typhoon and perhaps a Super Typhoon. Current forecasts run the winds up to 130 kts…that’s cat 4 status. Perhaps more troubling is that the forecast track is much closer to the Philippines as the storm makes its way toward Taiwan. If this track and strength holds true, then there will be strong winds and very heavy rains in parts of the northern Philippines. Manila will be affected. The closest the storm comes to the island is on Friday with winds offshore near the center of 115 to 120 kts. I kinda pooh-poohed this yesterday but this track is getting a little too close for comfort. It will be a problem for Taiwan and could be extremely problematic for the Philippines.
The Joint Typhoon Warning Center is providing data regarding the forecast and the reasoning behind the forecast.
Weather Bottom Line: So much for my fearless forecast…no one got to the 30′s this morning! Missed it by a few degrees as clouds hung around a little longer than I thought that they would. It did get down to 41 in Bloomington and 43 in Huntingburg, which is about equal to other minimums in the area. Its still going to be cool but I think we missed our chance to get to the 30′s is probably gone for the time being. Meanwhile, look at the map below:
Fall is on the way. We are still on track for storms on Friday. Thursday looks great after a cool start with a nice mild afternoon. We have a return flow with a storm system ejecting our way. Now, it does not appear as if there will be enough time to load up the atmosphere sufficiently to produce severe storms but its still worth keeping an eye on. Look for rain and t’storms though on Friday followed by another round of the type of weather we’ve seen the last few days with highs in the 60′s and lows in the low to mid 40′s for the weekend.