There are serious climate scientists who believe that 110% of recent climate change is due to human emissions of CO2. They think that natural variability is pushing down temperatures, canceling 10% of the effect of our greenhouse gases. There is apparently no room in their world for deforestation, black soot, etc. Greenhouse gases uber alles!
Humans do a number of things that affect the climate. Emitting greenhouse gases is the one that gets all the attention. But deforestation, black carbon, aerosols, changes in land use and land cover, reservoirs behind dams, all change the climate. Production of cement is estimated to emit 5% of all CO2. That’s as much as is estimated for air travel.
I haven’t seen a table anywhere that shows the estimated contributions as a percentage of the whole. What I have seen are charts of those that contribute to radiative forcing, such as this one:
But I’d like to see a list of all contributions to global warming, such as black carbon. Back in 2001, Stanford scientist Mark Jacobsen wrote, “”Soot - or black carbon may be responsible for 15 to 30 percent of global warming, yet it’s not even considered in any of the discussions about controlling climate change.”
Then for 13 years we didn’t hear about it anymore. It resurfaced last year, but without percentage estimates.
When I first started covering climate change, deforestation was estimated to contribute 20% of our greenhouse gases. Now it’s down to 17%, due in part to lower deforestation but sadly also in part due to an increase in total emissions.
So, another bleg–does anyone have such a chart at hand?
It’s important. If we don’t have a simple attribution figure that is widely agreed on, we will not get the support we need.
This is the second part of the RAMA Initiative. Part 1 was Recognition. We spent a week with Viscount Monckton establishing that even a staunch skeptic is capable of recognizing climate change and that humans are capable of causing it. Attribution much exist and be accepted before we even talk about Mitigation and Adaptation, the other two components of the initiative.
So thanks in advance for the help.