Modeling the future of our climate is a complex task that not too many people understand. What do we know about how the Intergovernmental Panel on Climate Change (or IPCC) modeling actually works? Why has the modeling community decided to model emissions separately from socioeconomic scenarios? When we hear that the RCP8.5 emissions scenario is considered a “business as usual” scenario, what assumptions are we making about all that business? And are those assumptions reasonable? Is there a climate scenario that represents an optimistic view of energy transition over the coming decades? And if so, what does it assume about the energy technologies that we will switch away from, and switch to?
These and many other questions are answered in this two-hour discussion on emissions modeling by an expert climate modeler from the National Center for Atmospheric Research (NCAR), who co-chairs the working group on future scenarios for impacts, adaptation and vulnerability indicators of the International Committee On New Integrated Climate Change Assessment Scenarios. It’s a wonktastic deep dive into an esoteric subject… and it just may leave you feeling a lot more hopeful about the prospects for energy transition, and for our planet.
When we hear about the emissions scenarios used in the Intergovernmental Panel on Climate Change (IPCC) reports, do we really understand what they’re assuming about future fossil fuel combustion? And what do these emissions scenarios imply about the steps needed to achieve climate policy goals and decarbonize our energy system? For example, when you hear about the worst-case warming scenario known as RCP8.5, do you know that it is based on projections for a 10-fold increase in global coal consumption through the end of this century? Or that many of the estimates of future fossil fuel combustion in these scenarios are based on very old assumptions about how the energy system could develop in the future? And how can we square scenarios like these with our contemporary reality, in which coal is in decline and the world is turning to renewables because they have become the cheapest options for generating power? How should we actually think about the influence that the global energy system will have on the climate over the next century? In this fifth part of our mini-series on climate science, researcher (and Energy Transition Show producer) Justin Ritchie helps us understand what the IPCC scenarios really mean, and how they can be improved to offer better policy guidance.