i have friends who are studying barrier systems that ahave lookd at everything that has formed and they are seeing evidence the sea level is rising faster than the last 7,500 years. barrier island didn't exist at that period along the texas and louisiana coast. we are getting into a period of instability as this increases. and if we're going to have large built infrastructure like a dike plat placed in these areas we are going to have have to ask if the trends continue what are the effective countermeasures that we can take. these are tremendous impacts on the coastline and i don't think we have fully comprehended at in stage what the future holds. certainly the modeling is going to help us determine that. >> mr. chairman, if i can add, there is an important component that has to be introduced into this discussion in addition to the climate change impacts. we recognize that there are periods of several decades when we see increased and decreased frequency and intensity of hurricane, the multi-decadal oscillation and the question is how much of that is continuing to happen. so, as we hav