The water along the coast keeps things mild in California, but as soon as you get into the mainland a bit, it can get very hot. I used to live in San Jose, and one weekend it was 105 and my air conditioner went out, so I drove 40 min to San Fransisco, and had to put on a sweater. weird climate in Ca.
anyway I agree, you should find a way to limit the sunlight in warmer months of the year. by the way I love your set up. and do you know of anyone else, growing Mangoes in Greece? that is so neat.