The next book on the list is Lenore Newman and Evan DG Fraser, Dinner On Mars. Here you learn of a maximum temperature for the plants we rely upon. Above that temperature, plants hold their breath - they stop transpiration. They outlast the Nubian summers that way.
I say "you" because we, who read Centauri Dreams last week, already knew: "Substantial extension of the lifetime of the terrestrial biosphere". The plants might not in fact die off in the great heating our Sun will give them. Some - like Dichanthelium lanuginosum - might last until 1.6-1.86 Gy from now (6.17-6.427 Gy from main-sequence). Good news for us; good news for other aging systems. (Although absent losing our Moon in a Newtonian event, Aldiss' particular vision won't happen.)
As for carbon-reduction events, we still must beware coming Pangaea continent-gatherings. The amalgamation should raise mountains. Monsoons will weather the rock... until those mountains wear down. The question moves from low-atmo CO2 to surface phosphour - always limited (some say the Amazon's long fertility only happened because of the Chicxulub accident). Can Earth count on more accidents? volcanoes in a frustrated Venerean surface?
Aaaand there's our segue for Newman (vegan) and Fraser to start farms up off this doomed planet. They were talking outer Mars at half irradiance; this post aims at the 1.35-1.91 range, or even 1 for our Lagranges, heliosynchs, and that fortnight-daylit Moon. Given hotter arboreta, Venus colonists don't need to worry - as much - keeping their floating farms cool. It still might worry human technicians but then, they're probably not getting into the greenhouse too often either, given the carbon-dioxide and always-on-illumination in there. It also means farms in space-stations might not demand a priority for those radiators.
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