MIAMI (AP) — During a hurricane, storm surge is one of the greatest threats to life and land, yet many people don't understand the dire warnings from forecasters to get out of its way. So this season, they hope to offer easy-to-understand, color-coded maps and change the way they talk to the public.
Simply put, storm surge is the abnormal rise of sea water. Predicting it is far more complicated, and so is explaining it, as forecasters at the National Hurricane Center discovered, again, during a review of Superstorm Sandy.
"Scientists by their very nature use very sophisticated language, technical language," said Jamie Rhome, leader of the hurricane center's storm surge team. "It turns out that nobody else understands what we're talking about. So once we figured that out, we started using more plain language."
Forecasts during Sandy were exceptionally accurate, but often confusing. Perhaps because so many things contribute to storm surge: intensity, pressure, forward speed, size, where it makes landfall and other factors.
Most people believe storm surge is a wall of water, similar to a tsunami, but it's actually just sea water being pushed toward the shore by winds. It can happen quickly and move miles inland, flooding areas not accustomed to being inundated with sea water.
Large death tolls have been blamed storm surge. At least 1,500 people died during Hurricane Katrina either directly or indirectly because of storm surge, the hurricane center said.
To better explain the danger, forecasters talked to focus groups consisting of local and state officials, law enforcement and hospital associations and other people from Maine to New Orleans. One thing they found out is that when they talk about storm surge, they should say "height" instead of "depth" when explaining how water levels might change.
"We were using 'depth,' thinking this was very clear. It turns out that nobody else does," Rhome said. "They're waiting for height, how high it is, and I would never have guessed in a million years that one word — one word — makes a difference in how people interpret something."
Forecasters also will try to stress that the storm surge isn't just from the ocean and can come from other bodies of water such as sounds, bays and lakes, sometimes well inland.
The hurricane center also plans to show people where to expect storm surge with high-resolution, color-coded maps, much like a radar map on the local news showing rain and severe weather. If forecasters can't post the maps on the hurricane center's website this storm season, which begins June 1, the plan is to have the maps ready in 2014.
The storm season is expected to be a busy one, with federal forecasters on Thursday predicting 13 to 20 named Atlantic storms, seven to 11 of which will strengthen to hurricanes. Three to six of those are forecast to become major hurricanes.