Last August, the first of the three reports, which prompted the UN to declare “code red, ” outlined the physical science of climate change while a third report coming out in March will be more about what can be done to curb and adapt to global warming. Without getting into specifics, report co-chair Hans-Otto Poertner said the science is clear that there are limits — including temperature limits — to what key ecosystems, species, and humans can withstand. And in some places, warming is near those limits and in a few cases, such as much of the world's coral reefs, have even passed them. “We are losing living spaces for species and for ourselves as well,” Poertner, a German biologist said in a press briefing last week. “Because with climate change, some parts of the planet would become uninhabitable.”