Global Climate Change -The Quantifiable Sustainability Challenge

                                                                                          By Frank Princiotta

 The presentation provides an updated analysis of the projected warming the earth is likely to experience in the decades ahead, the emission reductions needed to constrain this warming, and the technologies needed to achieve these emission reductions. Humanity is on an unsustainable trajectory; developmental pressures, spawned by an increasing demand for resource intensive goods, foods and services, are altering the planet in ways that threaten the long-term well being of humans and other species. Transparent modeling tools and the most recent literature are used, to quantify the challenge posed by climate change and potential technological remedies. The presentation examines forces driving CO2 emissions, how different emission trajectories could affect warming this century, a discussion of mitigation options, and R&D priorities. Major focus is on the power generation and mobile source sectors both globally & for the U.S. It is concluded that it is too late too avoid substantial warming; the best result that appears achievable, would be to constrain warming to about 2.5 ºC (range of 1.8 to 3.2 ºC) above preindustrial levels by 2100. In order to constrain warming to such a level, the current annual 3% global CO2 growth rate must transform to a 3 to 4% annual decrease rate for decades. Further, the current generation of energy generation and end use technologies are capable of achieving less than half of the emission reduction needed for such a major mitigation program. New technologies will have to be developed and deployed at a rapid rate, especially for the key power generation and transportation sectors. Given the magnitude of the technology challenge, societal changes & geoengineering options are discussed as potential supplementary mitigation options.