I do hope that everyone understands that there has not ever been a "computer model" that accurately predicted the future of anything. I am a software engineer, so you might say I have some experience with this. But let's assume this one is right. We gain 3 degrees temperature. Last summer, temperature here reached 112 degrees. Would 115 be even remotely a significant change? No. It would not. And sea levels? Does anyone ever stop to think that if you melt ice in water, there is no change at all in "level" It already displaces all the volume of water it is going to by floating. You can do this experiment yourself, on a small scale. Get a glass of water and put a large chunk of ice in it. Mark on the glass where the water level is. When the ice has melted, the water level will still be exactly where it was. The ice mass that exists on land is a very small portion of polar ice. And, finally, it is universally recognised that slightly higher temperatures would increase arable land (that is, useful farming land), and greatly benefit native wildlife.
All in all, I think the benefits of global warming would actually be quite agreeable. Well, except to those who had hoped to use it to drum up a fake "crisis" in order to steal money from you. They aren't going to be too happy about it.