solved You are a new First Officer on a fractionally owned

You are a new First Officer on a fractionally owned Falcon 9000 flying with a Captain you have never met. The weather is severe clear. It is a short flight from Melbourne, FL to Tampa, FL where you will pick-up your passengers. During the climb through 3,000′ the Captain wants you to request an altitude to FL 160, instead of the assigned altitude of 9,000′ where the temperature forecast is 5o C. You would prefer to not  spend so much time climbing to 16,000′ and instead make 9,000′ your cruise altitude.
From what you know of the effects of the atmosphere on aircraft behavior, which course of action do you think is better and why?