Welcome to Hard Talk on the BBC World Service with me, Stephen Sacker.

My guest today is a geophysicist and climatologist whose place at the forefront of the

scientific debate about climate change was guaranteed when he came up with the notion of a hockey

stick curve to graphically describe the dramatic rise in global temperatures that followed

the industrialization of the Western world. Michael Mann's findings and the causal link he posited

between warming temperatures and increased man-made greenhouse gas emissions were initially

denied by skeptics, many of them associated

with the fossil fuel industry. But now the science has been proven beyond reasonable doubt.

Man-made climate change is real, and it represents a massive, pressing challenge to all of humanity.

Now the question is, what to do about it?

The Biden administration is showing signs that it is ready to lead global efforts to decarbonize the world economy. But it's too early to judge whether words will be matched by action. Michael Mann says

a new climate war is unfolding. Well, if that's the

case, then who are today's biggest climate enemies? Well, he joins me now on the line from

Pennsylvania. Welcome to Hard Talk. Thanks. It's good to be with you. It's great to have you on the show.

Let us start with

the COVID pandemic and the global economic slowdown that came with it. There's some pretty

dramatic figures which suggest that carbon emissions worldwide may have been cut by something like

six or seven percent last year as a result of what happened. Can we see that as of any long-term

significance? Well, I mean, that's the good news, right? We saw a decrease in carbon emissions of

about 7 percent. And if we can keep that up, year after year for the next 10 years, that would

put us on the path to keeping warming below catastrophic levels

below 1.5 degrees Celsius. That's the good news. The bad news is that that was largely a temporary

...