This comprehensive MAHB article with revealing graphs mapping increases and tables analyzing sources, is the best short update on human production of atmospheric CO2 to 2018 that I have read. The accelerating trajectories of CO2 emissions to the current 411 ppm level far exceed the highest amount ever observed in the atmosphere during the last 800000 years.This recent relentless rise in CO2 shows a remarkably constant relationship with fossil-fuel burning, and can be well accounted for based on the simple premise that about 60 percent of fossil-fuel emissions stay in the air.
The author concludes the article as follows:
Today, we stand on the threshold of a new geologic era. What is happening is human caused. This does not augur well for the future for if we were to continue fossil fuel use with business as usual such that humanity exhausts the reserves over the next few centuries, CO2 would inexorably continue to rise to levels on the order of 1500 ppm.
The atmosphere would then not return to pre-industrial levels for even tens of thousands of years into the future. Figure 3 not only conveys the scientific measurements, it shows a stunning difference between today and the past 800,000 years. It also underscores the fact that humans have a great capacity to change atmospheric CO2, and therefore the climate on our planet.
The planet Venus suffers from runaway greenhouse effect, which results in keeping its temperature at 400o C . Its atmosphere is mostly carbon dioxide that comes from carbon cycling from molten rocks.
The condition of our Earth is ‘Anthropocene’, in other words is human made. Is it possible that we will end up like Venus one day in our reckless burning of fossil fuels?
This link is to the MAHB debate graph which allows search and comments on How to navigate the global 21st century?
Two months of heat wave in western Europe have prompted this statement from Michael Mann, a high profile climate scientist from Penn State U reported in a Guardian interview. It likens the relationship between global warming and extreme weather events to the correlation between smoking and cancer that was so long denied by the tobacco industry. Mann claims that AGW doubles the chances of these extreme events which also have seen devastating floods and wildfires around the world in recent months. And here is a BBC report on the association between the recent heatwave and climate change.