Today I find myself in Hermosillo, state capital of Sonora in the north-west of Mexico, 200 miles from the US border. It's in the middle of nowhere, arid and incredibly hot. Yesterday was a jaw-dropping 46C. Today, a mere 42C but still, I think, the highest temperature I've experienced anywhere in the world. I'm here to sign an MoU with their Minister of Culture, as part of a broader series of events which include trade and education. The formality of the occasion means I have to wear a suit and tie but thankfully it's very dry heat and amazingly I hardly break sweat.