Dissertation Defense: Robert Fofrich

Title: Constraints to Climate Change Mitigation and Adaptation

Abstract: Stabilizing rising global temperatures requires a swift and marked decline in anthropogenic emissions, a vast majority of which originate from fossil energy sources. Thus, mitigating future climate change entails a rapid transition away from CO2 generating energy infrastructure which are generally long-lasting and economically costly. Nonetheless, climate change mitigation pathways which successfully avoid more than 2oC in preindustrial warming do so by drastically changing the operational and retirement schedules of fossil-fired power generators which have historically operated for around 40-years. Current climate change mitigation models consistent with international climate targets (i.e., keeping global warming well below 1.5°C or 2°C) retire fossil-fired power plants up to three decades earlier than has been the case historically. While the premature retirement of fossil-fired generating assets is possible, it can be economically and politically costly, and result in the loss of trillions of dollars of capital investment, and perhaps even jeopardize the stability of global financial systems if not adequately managed and anticipated. If instead, additional fossil-fired power plants are commissioned and power generators are allowed to operate as they have historically, the resulting emissions are incompatible with more ambitious climate change mitigation targets without the equivalent removal of atmospheric CO2.

Nonetheless, unabated climate change will have much larger impacts on the global economy in addition to social and natural consequences. For instance, climate change is expected to have mixed impacts on agricultural productivity reducing yields in historically warmer regions while possibly benefiting cultivation at higher latitudes. Substantial research effort has thus been dedicated to evaluating the adaptive potential of different farming practices and new crop varieties, and numerous observations suggest that the locations of major crops worldwide have shifted in relation to recent increases in growing season temperatures—i.e., adaptation by migration. Here, I project future shifts in the agroecological zones of major rainfed grain crops (i.e., maize, rice, soybean, and wheat) if these crops move to track their historic climate ranges as the climate changes, and explore the implications for global food security, sovereignty, and equity. Although the impacts of climate change on agriculture might be partially mitigated through improved farming practices and more resilient crop cultivars, these results emphasize the large extent to which a warming planet may disrupt global food production in the coming years. Thus, highlighting the urgent need for planning.