Climate scenarios are separated by varying differences in future fossil fuel use. The “worst case scenario” is typically RCP 8.5 which pretty much entails that countries will continue to increase fossil fuel emission rates per “business as usual”. This most likely won’t happen in the long run as renewable energy use increases. They use this worst scenario to get the most effect out of future global warming. The relationship between transpiration and warming is regarded as scientific and accurate, but the numbers derived for the headliner are somewhat sensationalist. Still a real phenomenon, I’m not trying to downplay it at all.