3. THERE IS A GENERAL CONSENSIS that the Earth's temperature increase should not be allowed to exceed 1.5°C.
4. THERE IS ALSO A CONSENSIS that this is virtually impossible and that the target should be 2°C despite its higher risk.
5. ACHIEVING ANY PARTICULAR GOAL is complicated by the politics within each country, especially in the United States, which has taken a highly irrational anti-science position and is making decions that exacerbate the problems. It is likely, in my opinion, that the United States position could be decisive.
6. A REVIEW OF THE LITERATURE indicates assessments from serious to near panic.
7. NUMEROUS EXPERTS HAVE RECOMMENDED urgent development of negative emissions systems to provide large scale active carbon removal from the atmosphere in addition to urget reduction in CO2 ouput.
8. HOWEVER CO2 OUTPUT output at this point is rising for a number of reasons and no country has shown a sufficiently aggressive approach to reduction. (See illustration below).
9. ACTIVE CARBON REMOVAL, although demonstrated in pilot projects, has not been the subject of thorough resarch and evalution and no such program has been started. Some researchers have proposed deployment of hundreds of thousands of units at enormous costs yet there is no indication that goverments are prepared to consider such schemes.
10. AN ADDITIONAL COMPLICATION is the psychological effect on the public of discussions of temperature increases in the single digits or even fractions of degrees. This leads, I believe, to a lack of urgency not only by the public but by most of the public media. Additionally. although serious problems could be only 10 or 20 years away this seeem remote enough to human psychology to lead to a lack of urgency.
11. ON THE OPPOSITE SIDE are fears of temperature increases that may look linear actually turning out to be the start of exponential increases which could be catastrophic. A simple trendline analyis of NASA temperature data from 1880 to 2017 either by curve fitting or trendline polynominal expansions show the beginnings of exponential increases in temperature. These trendlines show, as might be expected, similar numbers as other methods in the short term, suggesting accelerating increases in the longer term. The complexities of the climate indicate that such exponential increases cannot be ruled out. Indeed, there are suggestions that lacking exceedingly rapid reponse today could lead to mitigations costing future generations hundreds of trillions of dollars.
12. IN SUMMARY the present situation is sufficiently serious and uncertain as to warrent an extremely pessimistic picture for future climate change impact.
Further, I consider that situations as complex as this may yield to an "engineering" intuitive approach to summarizing an intractable amount of research, information, observation and opinions.
Subsequent pages include links to opinions and studies from which the above was derived.