Fair Plan 7: Earth’s Climate Future = Humanity’s Choice

Abstract

How to cite this paper: Schlesinger, M.E., Ring, M., Cross, E.F. AbstractEarth's climate future is in the hands of humanity. If emissions of greenhouse gases remain unabated, Earth's climate will return to the climate of the Late Eocene, 35 million years ago, when sea level was 73 meters (240 feet) higher than today. Should that occur, many coastal cities around the world would be inundated. Moreover the Global Warming of this unabated Reference case will be comparable to the Global Warming from the Last Glacial Maximum 21,000 years ago to the beginning of the Holocene interglacial climate 11,000 years ago. However, this human-caused Global Warming would occur 50 times faster than that caused by nature. Alternatively, humanity can mitigate greenhouse-gas emissions to keep Global Warming below the 2˚C maximum adopted by the United Nations Framework Convention on Climate Change "to prevent dangerous anthropogenic interference with the climate system". This mitigation can either be done rapidly, as in the "80/50" Plan to reduce greenhouse-gas emissions 80% by 2050, or much more slowly, from 2020 to 2100, as in the Fair Plan to Safeguard Earth's Climate. The Fair Plan is a compromise between doing nothing, as in the Reference case, and rapidly reducing greenhouse-gas emissions, as in the 80/50 Plan. Regardless of the Plan chosen to reduce greenhouse-gas emissions to keep Global Warming below the UNFCCC limit of 2˚C (3.6˚F), it should not be tantamount to our saying to one of our planetary spacecraft, Bon Voyage, call us when you get to your planetary destination. Rather, as with our spacecraft, the chosen climate-change policy should be monitored throughout the 21 st century and Midcourse Corrections made thereto as needed to keep our "Climate Spacecraft" on track to achieve its "Climate Target". KeywordsEarth's Climate Future M. E. Schlesinger et al. 346

Fair Plan 8: Earth’s Climate Future—Pope Francis’ Population Mistake

“…The CO 2 concentration for the Reference case rises to 1928 parts per million by volume (ppmv) in 2237 and then, as a result of the natural sinks, decreases to 1875 ppmv in 2300. The CO 2 concentration continues to decrease to about 1750 ppmv in 2600 and remains there over the last 400 years of the third millennium (see Fair Plan 7 [17]). This CO 2 concentration is more than six times the preindustrial concentration of 277 ppmv.…”

“…We have used these scenarios in several of our papers published beginning in 2000 [6]- [9]. While we have used the more recently developed Reference Concentration Pathway (RCP) scenarios [10] in our more recent Fair Plan to Safeguard Earth's Climate papers [11]- [17], the SRES scenarios are ideally suitable for our present purpose.…”

“…The Fair Plan to Safeguard Earth's Climate [11]- [17] was crafted by us to satisfy three objectives: Objective 1: The cumulative trade-adjusted CO 2 emissions by the developing countries equal the cumulative trade-adjusted CO 2 emissions by the developed countries. Trade-adjusted emissions mean the emissions incurred by country A to export goods and/or services to country B are debited to country B, not country A.…”

2016 Evaluation of Fair Plan 3: Outlook for Global Temperature Change throughout the 21<sup>st</sup> Century

“…The combined model includes 33 additional greenhouse gases, three aerosols, and three other radiative-forcing factors. These are listed in Table 4 of "Fair Plan 7: Earth's Climate Future = Humanity's Choice" [6]. …”

“…(N.B. The calculations of the CO 2 concentration were performed throughout the third millennium in "Fair Plan 7: Earth's Climate Future = Humanity's Choice" [6]. )…”