The atmospheric CO2 concentration is rising - mainly due to the burning of fossil fuels. It's agreed that this build-up will, in itself, induce a long-term warming trend, superimposed on all the other complicated effects that make climate fluctuate.
Collective human actions are transforming, even ravaging, the biosphere - perhaps irreversibly - through global warming and loss of biodiversity.
The challenge of global warming should stimulate a whole raft of manifestly benign innovations - for conserving energy and generating it by 'clean' means (biofuels, innovative renewables, carbon sequestration, and nuclear fusion).
Given the scale of issues like global warming and epidemic disease, we shouldn't underestimate the importance of a can-do attitude to science rather than a can't-afford-it attitude.