Emergency management directors bracing for heavy winds and high tides along North Carolinas coast this hurricane season will have new data from a storm-modeling computer program at UNC-Chapel Hill to show where and how high the water is expected to rise.
The Renaissance Computing Institute, known as RENCI, is offering detailed storm-surge data in a format that allows local emergency managers to create their own customized analysis of incoming hurricanes, noreasters and other weather events, said Brian Blanton, senior scientist and oceanographer at UNC.
The typical way you assess storm surge is to look at a big region, but the true nature of the coastline and tidal inlets can have a big impact on how storm surge is going to develop in a specific location, Blanton said. This will give these managers the opportunity to take the data, put it into their own systems and do their own analysis.
The information comes from RENCIs Surge Guidance System, which uses real-time information on weather conditions, ocean circulation patterns and wave height to evaluate predicted storm-surge impacts along the Atlantic and Gulf coasts.
The data are being made available for the first time this year to county and state emergency management departments as a Shapefile, which allows it to be merged with local geographic information systems.
Our goal is to get this information down to the decision-making level as fast as possible during events, Blanton said.
Jessica Losego of the Institute for the Environment at UNC-Chapel Hill has been working with emergency management staff along the North Carolina coast to explain the advantages of the program and to gather feedback on other types of information that might be helpful in planning for a weather emergency.
They are certainly interested in the surge information and also like to look at wind information so we added information based on feedback that includes the onset time of tropical force wind, Losego said. Thats how they decide when to start their evacuation.
Additional information on rainfall was added to the storm-modeling program at the request of emergency planners.
Rainfall gives them an idea of how much total water is going to wind up in the county, in addition to storm surge, Losego said.
Hurricane season along the Atlantic Coast runs from June 1 to Nov. 30, with activity typically peaking in late summer.
N.H. Sandy Sanderson, the Dare County emergency management coordinator, said he welcomes additional help to determine how much stormwater will be flowing onto land and over highways in his district.
On barrier islands, storm surge can be a strong factor we need to come up with a way to determine how deep water is going to be at a particular point, Sanderson said. This will help emergency managers to be able to digest and spit out the information in a timely fashion.
Having the ability to create maps and other visual displays related to storm information is another plus.
The graphics that can be generated go a long way toward convincing people to evacuate, if the situation calls for it, Sanderson said.
North Carolina has become a national leader in weather-related emergency preparedness because of a combination of extensive floodplain mapping and the computerized weather projections developed at UNC, said John Dorman, head of North Carolinas floodplain mapping program in the Department of Public Safety.
The states databases include land and underwater topography and an inventory of 5.2 million structures. When combined with RENCIs storm-surge computer modeling, emergency planners can get a realistic preview of what to expect, Dorman said.
It gives us an accurate understanding of what the water will do when it hits shore, Dorman said.