A question of heat

Greetings from sunny California! We are having a great time with the
grandparents and loving the sunny weather. Which brings up a question...

Kiddo has been nursing much more frequently since we arrived. Back home he
was eating every 3 hours or so. Here it has been every two. My mom
thinks that may be because it is warmer and he is sweating more. Anyone
have any experience with this or ideas? Thanks!