The premise is good. Lynas said that we cannot predict accurately when a three degree world will emerge, or a four degree world, but we can to some extent predict what will happen when we move into a three degree world, or a four degree world, whenever that happens. A good point.
He introduced me to the idea of fast and slow feedback loops. When Arctic sea ice melts, ice cover shrinks, replacing white, reflective ice with dark sea water, and this is an example of fast feedback. The exposed sea water absorbs much more of the sun's heat than ice, thus contributing to the warming: positive feedback. If a cold, moist peat bog experiences a warmer, drier climate, the peat slowly dries out, and aerobic bacteria can slowly oxidise the carbon in peat to carbon dioxide. This an example of slow feedback, and is also a positive feedback.
In a warming world, climate bands move towards the poles. I have read this before and still do not know why. The northern wheat belt will move north, and Canada, northern Europe, and Russia will do well in a warmer word. So will Sweden, where Greta comes from. In the southern hemisphere, the South American wheat belt will move south, and the narrowing of the South American continent will mean rather less land for wheat. In Australia, where I come from, the wheat belt in SE and SW Australia will move south, and like South America, will have less land.
Predicting the future, degree by degree, is an excellent way of presenting the information.
