Why is temperature such an issue for Formula 1 cars in Bahrain?

Renault Formula 1 team has explained why temperature is such a difficult factor to manage during the Bahrain Grand Prix weekend. In their technical briefing Chief Race Engineer, Ciaron Pilbeam talks about the temperature aspects.

Two weeks ago in Melbourne, two teams seemed to have problems with cooling. Renault honestly admitted that some things could be better (and will be better) in Bahrain while Ferrari denied everything and only indicated that it had found 'a solution to a problem'. Given the temperature alterations across different sessions in Bahrain, Pilbeam explains how they are going to attempt to manage proceedings.