"Drastic and sudden changes to the ecosystem in the Gulf can disrupt that -- sometimes permanently. The result of the change, even if it were as simple as you believe it to be (which it isn't), could be as negative as a hurricane would be."

The temperature change is not that drastic since the difference of the temperature change is less than what occurs between summer and winter. Since the difference is less than what normally occurs between summer and winter the negative impact would be far less than another Katrina. And the cooling of the loop current in the Gulf would have a huge impact on any storm crossing its path.Here is the proof.

Link: Scroll down just a little to view the article. I've done my homework on this and the idea will work.

http://www.usatoday.com/weather/huricane/science/warmpool.htm