Watch the pea: We should reduce CO2 emissions because that will reduce "associated pollutants" that allegedly might kill three million annually by 2100

Cleaner air from tackling climate change 'would save millions of lives' | Environment | theguardian.com

They found that 300,000-700,000 premature deaths a year would be avoided in 2030, 800,000 – 1.8 million in 2050 and 1.4 million to 3 million in 2100. By mid-century, the world's population is expected to peak at around 9 to 10 billion.

A key finding was that the value of the health benefits delivered by cutting a tonne of CO2 emissions was $50-$380, greater than the projected cost of cutting carbon in the next few decades. The benefits do not accrue from reductions in CO2 per se but because of associated pollutants released from burning fossil fuels.