Page 41 - Carbon Capitalism and Communication Confronting Climate Crisis

24 M.E. MANN AND B. BREVINI

MM: It’s true. And there’s been a fair amount of coverage about what the
pledges actually buy us in terms of curtailing further warming. And you can
tally up the net effect of all the pledges—it gets us about half way from
business as usual, which would be 5° by the end of the century. It gets us
half way to two degrees—it gets us in the middle, around 3.5°. It doesn’t
get us down to that two degree mark, which is what many scientists say is
the level at which we experience even more dangerous impacts of climate
change. But it gets us on the path. The idea is that Paris alone isn’t going to
solve the problem, but it creates a framework that can be built on further
with further reductions at the next conference—major conference of the
parties, which hopefully can get us below 2°.
Ultimately, any amount of additional warming is bad. So there’sno
really fixed level that sort of divides safe and dangerous. It’s really more an
ever-steeper downward slope rather than a cliff. And further we head down
that slope, the further we go down that highway, the worse things get. And
we want to take the soonest, earliest exit that we possibly can off that
highway. So 2 °C warming relative to pre-industrial is the result of
somewhat subjective assessments—when you look across the various sec-
tors that climate change impacts—food, water, health, loss of coastal
property, the economy, a whole host of metrics of climate change impacts
—and you look at the various studies that have been done estimating how
those impacts depend on warming, you find that above 2 °C is where all
the impacts really start to look negative. At less warming there’s actually the
possibility that some impacts are minimal or even slightly positive, but once
you get above 2 °C warming, that’s where pretty much all of the assessed
impacts start to look negative and so you’re looking for some reasonable
line in the sand to draw where we can say we really see the worst impacts of
climate change. Two degrees Celsius is pretty reasonable.
BB: I understand that. Reading 2036 and 2038 as the deadline for us
seems dangerously close.
MM: Yeah I know, that’s right. For us to continue as business as usual with
burning of fossil fuels—we pass that two degree threshold very quickly. So
without any action we will cross that threshold in a matter of a couple of
decades or less.
BB: In your new book you address the problems of geoengineering as
a proposed solution to the climate crisis. What are the issues with this,
as you see it?