4:37 p.m., Oct. 31, 2012--The Office of the State Climatologist and the Delaware Geological Survey (DGS), both based at the University of Delaware, provided the Delaware Emergency Management Agency (DEMA) and the National Weather Service with weather, coastal flooding and stream flooding information for Delaware during Hurricane Sandy.
Delaware State Climatologist Daniel Leathers, a professor of geography at UD, and Kelvin Ramsey, a scientist at DGS, answered some questions about this major storm for UDaily. Timothy Targett, professor of marine biosciences, also responds to a question about marine life.
How does Hurricane Sandy compare to the infamous 1962 nor’easter that pounded the Delaware coast? Has there been another hurricane like it in recent history?
Dan Leathers: Sandy is quite unique in Delaware storm history. Sandy and the ’62 storm are quite different, although they had some similar effects. Flooding along the Delaware Atlantic coast was very bad in each. Sandy began as a tropical system and slowly changed to a mid-latitude cyclone. The ’62 storm in March of that year was a mid-latitude cyclone throughout its life cycle. Both were “blocked” from moving north by a high-pressure system to the north. Sandy actually made landfall, while the ’62 storm was always off the coast.
What has been most unusual about this storm, meteorologically speaking?
Dan Leathers: The most unusual thing about this storm was its track for this time of year. It is very unusual for any tropical system to turn west into the mid-Atlantic any time of the year (although it has happened). It is very unusual for a tropical system to come this far north and then turn west, as Sandy did, so late in the tropical season.
What have been some of Hurricane Sandy’s most damaging impacts on Delaware?
Dan Leathers: It looks like the coastal flooding issues along the Atlantic Coast and along the Delaware Bay will end up being the largest impact on Delaware. We had very heavy rainfall across the entire state, ranging from more than 10 inches along the Atlantic Coast to around 6 inches in northern New Castle County. We were very lucky to avoid severe stream flooding in New Castle County, as 5 to 7 inches of rain fell across the basins of the Red Clay and White Clay creeks and across the Brandywine Basin. We also were lucky to have missed the highest wind speeds in this storm.
How significant was coastal flooding? Was UD’s Coastal Flood Monitoring System in operation throughout the storm?
Kelvin Ramsey: Coastal flooding was widespread. Record flooding in terms of tide height was recorded in Little Assawoman and Rehoboth bays and in the tidal Delaware River from the mouth of the Chesapeake and Delaware Canal northward. The tide heights and stream level heights related to the storm will be posted on the Delaware Geological Survey (DGS) website.
Dan Leathers: The Coastal Flood Monitoring System was in operation during the storm, and the Delaware Environmental Observing System (DEOS) was used extensively throughout the event by DEMA and the National Weather Service to monitor conditions across Delaware.
What condition are the state’s beaches in?
Kelvin Ramsey: I have not been to the coast. From the reports I have heard, the dunes for the most part held in areas where beach nourishment has been conducted. It is too soon to determine the condition of the beaches in front of the dunes.
What will happen to the sand that Hurricane Sandy eroded from the state’s beaches?
Kelvin Ramsey: Often in storms, the sand from the beaches is moved offshore. Some of this sand will return over the next several weeks to the beaches once normal wind and wave conditions occur. Where the dunes are breached, the sand is washed inland onto the barrier, and where the barrier is narrow, into the marshes or tidal waters behind the barriers.
What likely happened to marine life, such as fish, during the storm?
Tim Targett: Some species of fish are known to move to deeper water in response to approaching storms. Plus, most species would likely move into deeper water to avoid the waves in shallow habitats once the storm arrived, even if they had not left before.
This storm occurred late in the hurricane season and affected a broad region. Is climate change having an impact on such storms — by extending the “hurricane season” or contributing to broader, damaging impacts of such storms?
Dan Leathers: It is nearly impossible to associate a single meteorological event to climate change. Although a changing climate can provide a new “background state” for meteorological events to occur, we cannot say that this or other single events are directly related to climate change. As more and more “single events” occur over time and become the “average,” we can better say if this change is a result of a changing climate.
Article by Tracey Bryant