Monday, June 4, 2007

Automatic Triggering of Severe Weather Forecast

NCSA Enables Automatic Triggering of Severe Weather Forecast

The National Center for Supercomputing Applications (NCSA) has developed tools and is providing compute resources to enable atmospheric scientists to automatically produce high-resolution storm forecasts in response to real-world conditions. Hundreds of computer forecasts have been triggered by storm watches and weather discussions over the past several months.

"The idea is that when a critical need exists, we need to provide resources quickly," said Jay Alameda, leader of the middleware development team at NCSA.

The triggered forecasting capability is being rolled out as part of the 2007 Spring Experiment, hosted by the NOAA Hazardous Weather Testbed. The experiment, which runs during the storm-heavy season from mid-April through June, provides forecasters with a first look at the latest atmospheric science research and technology and familiarizes researchers with the needs and challenges of forecasters in the field.

As part of the spring experiment's effort to improve forecasting of severe weather, NCSA has demonstrated the capability to trigger computational simulations in response to real-world conditions. When the NOAA Storm Prediction Center in Norman, Oklahoma, issues a severe thunderstorm or tornado watch, or a discussion of current conditions points to the potential for storms to develop, this information automatically initiates computational forecasts using the WRF forecasting code on one of the compute systems (currently Tungsten or Mercury) that NCSA contributes to the TeraGrid.

"One of the things that's really unique about this is the unpredictability," said Brian Jewett, an atmospheric scientist at the University of Illinois at Urbana-Champaign who is working closely with NCSA on the development of advanced tools and technologies for weather forecasting. Jewett explained that watches can come at any time, and they often come in batches. So multiple simulations can be spawned around the clock.

NCSA's Ensemble Broker software is designed to manage multiple computational jobs. To support the triggered simulation capability, NCSA enhanced the Ensemble Broker so it can submit jobs to the Moab cluster workload management package. The Ensemble Broker also stores numerous aspects of workflow submission and execution, which Jewett said makes it easier for researchers to reproduce the steps they took to get their results and facilitates collaborating with others.

Currently, a single forecast is trigged for each watch or discussion; the forecast is carried out at two resolutions -- one with a grid spacing of 18 kilometers and the other at a high resolution of 2 kilometers. Details on the triggered forecasts are available online at

Because so many variables affect weather, forecasts are very sensitive to subtle changes in conditions. Atmospheric scientists often use ensemble forecasting to account for these uncertainties, carrying out multiple forecasts with slightly different conditions and configurations. Looking at the results of all of the simulations often provides forecasters with a best estimate for the ensuing weather conditions and gives a measure of the confidence in that forecast. The Ensemble Broker was designed to manage the thousands of jobs required for ensemble forecasting and other parameter studies.

"It's exciting for me to see the capabilities," Jewett said. "It's really general, it's not weather specific, and it's deceptively powerful."

For the spring experiment, all of the triggered simulations are being carried out on NCSA systems, but work has begun toward dynamic job deployment, meaning that once a forecast is submitted the best resource would be identified and the calculations would be carried out on whichever TeraGrid resource could complete the work most quickly. This type of dynamic deployment could be key during a national emergency -- whether it's a hurricane heading for the coast or an infectious disease spreading from person to person.

NCSA's work on tools to support advanced weather modeling and forecasting is supported by the National Science Foundation. NCSA is a partner in LEAD (Linked Environments for Atmospheric Discovery), an NSF-supported effort to create an integrated, scalable framework for identifying, accessing, preparing, predicting, managing, analyzing, and visualizing a broad array of meteorological data and model output independent of format and physical location and in a dynamically adaptive manner.


Source: National Center for Supercomputing Applications

High Sea's & Update On Sean Seamour II

This is the Saga Cruise Line's, Saga Rose. The vessels characteristics include, Gross Tonnage: 24,474 gt. Length: 620 ft. / 189 m. Crew: 350. Full Capacity: 620.

The Saga Rose was built in 1965 for Norwegian American Lines and was later assigned to Cunard and then purchased by Saga Cruises, a subsidiary of Saga Travel. The ship was previously known as the Sagafjord , Gripsholm and Saga Ruby.

Nov. 24th, 2006 Sailing from Southampton to Madeir, she hit a storm with 50 + kt. winds for three days and the storm did quite a bite of damage. Let's not also mention the unscheduled and interesting wild ride it's passengers got. Though these waves are not officially reported as freak waves, it will give you an idea what heavy sea states are like. Remember this storm did a lot of damage to the Saga Rose. While your also watching the video (Lower Left Side - Saga Rose - Point and Click ) remember that this is a 620 foot/189 meter ship! Listen to the bridge crew. These are experienced sailors. Now just imagine what a wave such as this could do to a 44 foot sail boat!

I have also added a dramatic video clip of the Cruise Ship Voyager
(Lower Left Side - Voyager - Point and Click )with 776 on board who was enroute between Spain's Balearic Islands to the Italian island of Sardinia and ran into Force 11 Winds (100km/hr) on 2 February 2005 off the coast of France. There was a report of a "giant wave" smashing the bridge window and knocking out electronics. Once again imagine a 44 foot sail boat in these seas!

Running down any known facts in the case of the Sean Seamour II is rather difficult. I again appeal to anyone with any information to contact me here. I have communicated with Dr. Paul C. Liu of NOAA's Great Lakes Environmental Research Laboratory (GLERL) with regards to the Sean Seamour II. The first thing Dr. Liu said was, "thank God they were rescued." Dr. Lui
referring to my email then went on to explain that, "as there is no eyewitness and there is no measurement, it is just not possible to substantiate it one way or the other. The current state of freak/rogue waves research just can not be of any help beyond that." However he goes on to say, "this case clearly occurred during a storm. We know that in general freak/rogue waves can happen during calm or storm conditions."

We know that wave surges can travel thousands of miles in any direction from any storm. Forget the fact that the Sean Seamour II ran into its trouble directly in the middle of a subtropical storm. I am still waiting to see what the National Hurricane Center has to say.

Stay tuned.