james clayton meets a shark tracker who's made a great white discovery. are there any moments that you filmed where you felt nervous for the people in the water? i'd say yes. we're starting the programme in kenya, where agriculture plays a huge part in many people's livelihoods. in fact, the industry employs more than 40% of the total population. but climate change is having a real impact on the crops there. and you might be surprised to find out what one of the most sensitive crop types is. flowers. they have a specific window for being grown and sold, and if the weather is out of sorts, it can completely derail the process. but technology can help, and shiona mccallum has spent a day on a rose farm in naivasha to find out more. our years are punctuated by times that we want to buy flowers — valentines, birthdays, christmases — and the chances are when you look in your bouquet, one of the stems would have been grown here in kenya. but like most places, this part of the world is not immune to the problems that climate change is bringing. rising temperatur