I'm reading a [review](https://www.nytimes.com/wirecutter/reviews/best-cake-pans/) of cake pans.

Most of the round pans in the review are 2 inches tall. However, there is one round pan in the review that is 2.5 inches tall, and the review had the following comment about it:

> 
> It baked an evenly golden cake, but it was half an inch taller than any other pan, tall enough to bake the top of the cake darker than any other.
> 
> 
> 

Why would baking a cake in a tall pan make the top of the cake darker?