Wharton's analysis of the more than 1 million flood insurance policies in force in Florida in 2005 showed that 98.3 percent of customers chose a deductible lower than the maximum amount; 80 percent of policyholders chose the lowest possible deductible of $500. The standard $500 deductible was discontinued in 2009 for high-risk flood zones; the current standard deductible is $1,000. It is a safe guess that people continue to let their deductible default to this new number and that they would appreciate knowing how much they could save by raising it. Higher deductibles on flood policies may be the key to convincing people that hanging on to a flood policy is in their best interest given the fact that flood risk has not diminished and, in fact, may be increasing.

We have been schooled by decades of exercises with the familiar Saffir-Simpson scale, and it may have had an unintended effect of masking flood risk. Since 1975, the Saffir-Simpson scale, with its five distinct categories for characterizing hurricane wind damage, has been the guidepost by which local authorities and coastal dwellers decide how to respond to an approaching storm. It has been a good tool for alerting people to possible impacts from storm-force winds, but it overlooks other hurricane-related impacts that are more devastating, such as storm surge and tornadoes. A newly patented hurricane scale hopes to change that.

Called the Integrated Kinetic Energy scale (IKE), it predicts the potential destruction for both wind and storm surge. Dr. Timothy Reinhold, senior vice president of research and chief engineer at the Insurance Institute for Business & Home Safety (IBHS), and Dr. Mark Powell, an atmospheric scientist with NOAA's Atlantic Oceanographic and Meteorological Laboratories, were awarded the IKE patent, which differentiates between the risk perception of wind and storm surge to more completely assess a hurricane's destructive potential.

While a surge height estimate was added to the original  Saffir-Simpson wind scale, the National Hurricane Center (NHC) took steps 2 years ago to make it clear that the Saffir-Simpson storm classification in its warnings is only based on maximum wind speeds. It is producing separate estimates of surge in feet for warnings. The estimated surge height depends on local conditions for which the NHC gives the following example: If 2008's Hurricane Ike made landfall in Palm Beach, the resulting storm surge would have been only 8 feet, rather than the 20 feet that occurred where Ike actually made landfall on the upper Texas coast. These wide disparities of surge impacts are due to differences in ocean/gulf depth and the shape of the ocean/gulf floor.

The Gulf waters off Texas are shallow, which enhances storm surge, while the deep ocean off southeastern Florida inhibits surge. However, 8 feet of water is no small amount, so the National Weather Service (NWS) will continue to educate people about the inundation expected at coastal and inland locales by providing estimates of surge in feet.

The IKE scale, while not an official NWS product, will be put to the test and then hopefully refined by continuing research. Its best use likely will be as an early warning of surge potential. Final surge estimates will always depend on local conditions and are best estimated by more sophisticated models that include wave setup, the depth and shape of the ocean/gulf floor, and the roughness of the land that is impacted.

When my own flood policy was coming up for renewal, I received a letter from FEMA that was direct and to the point. It stated that the risk of flooding is as real today as it was when my flood policy was first purchased. True enough. It is also true that storm surge does not correlate neatly to wind speeds, does not follow property boundaries, and that most of Florida is built over swamp land that Mother Nature may want to reclaim, at least for a short while after a heavy downpour. Flood insurance should be part of this reality over the long term, not merely for a 2 to 4-year period.