You seem to fail to relize that those summer and winter temps are just that, summer and winter. Animals behave differently during those time, do different things, are in different places. You cant just change the temp on them by 10-15 degrees then have it slowly change back, the animals would completely change what they are doing. You might cause a mass migration, or stop one. You certainly don't know. I certainly dont know. I doubt anyone really knows.

BTW, that link didn't provide any information that people here didn't already know. Cooling the waters would slow or stop hurricanes, yes its true, its all the other problems we are all woried about.
One more thing, thats a news article, not the best source for information. Look to scientific journals, university webpages, ect, for good quality information.