4: Overview of the Ten Solutions for Bending the Curve

Overview

In Chapter 1, we looked at the science of climate change. We saw the strong scientific consensus that human emissions of climate pollutants are causing warming of our planet on a scale not experienced in over 10,000 years. Continuing on a “business as usual” pathway could lead to dangerous and even catastrophic changes in the Earth’s climate, with severe adverse impacts on human and natural systems. We have at most a few decades to change this trajectory and bend the curve of warming. In this chapter, we will take an initial look at strategies to mitigate future climate change.

The challenges presented by climate change cannot be solved by technological innovations alone. Dealing with this problem will require changes in our attitudes toward each other and toward nature, as well as changes in our behavior. We will need a broad-based effort, with active involvement by individuals from a wide range of fields, including researchers, academics, engineers, community leaders, and ordinary citizens.

This book is organized around a set of ten solutions designed to bend the curve—to reverse the trend of increasing human greenhouse gas emissions and keep the planet below dangerous levels of warming. Until 2015 it was generally assumed that warming above 2°C would represent the threshold for danger. More recently, we have come to understand that the dangerous warming level is lower: 1.5°C. Warming limits, such as the 1.5°C goal, should be viewed as broad planning tools and not confused with a well-defined geophysical threshold for the onset of dangerous changes. As you learned in Chapter 1, dangerous impacts of climate changes have already begun at local levels in the form of intensified droughts, wildfires, hurricanes, and floods, among other extreme weather-related disasters. Such impacts are already being felt by several tens of millions; when the warming reaches 1.5°C to 2°C, 1 billion to 2 billion people could be affected adversely—at which stage, global warming may have to be renamed global heating, and climate change renamed climate disruption.

The ten solutions to climate change are organized under six solutions clusters. This set of six clusters and ten solutions was developed by a multidisciplinary group of over 50 experts from across the University of California system who came together in the summer of 2015 to discuss a comprehensive approach to combating global warming and climate change. Their findings and recommendations are included in the report Bending the Curve: 10 Scalable Solutions for Carbon Neutrality and Climate Stability.

Although the time to act is short, the good news is that we are not starting from zero. International agreements, including the Montreal Protocol on Substances that Deplete the Ozone Layer (Montreal Protocol), signed in 1987, and especially the Paris Agreement, signed in 2015, have laid the groundwork on which we can build future actions. The Montreal Protocol’s original focus was on banning emission of chlorofluorocarbons (CFCs) that damage the ozone layer. While damage to the ozone layer is a separate problem from climate change, those same CFCs have powerful climate-warming effects; per ton of emissions, the warming effects of CFCs are about 10,000 times stronger than the effect of carbon dioxide. If they had not been banned, current global warming would have been even greater. Moreover, the Montreal Protocol itself has been expanded to include climate change. The 2016 Kigali Amendment to the Montreal Protocol calls for the phaseout of hydrofluorocarbons (HFCs), which do not damage the ozone layer but have very significant warming effects (Box 1.3.1 in Chapter 1). The Montreal Protocol and the Kigali Amendment are discussed in more detail in Chapter 15.

The Paris Agreement represents a historic advance because it is the first international agreement on climate change to include commitments (albeit voluntary) from all nations on the planet. This agreement has its drawbacks; as we will see in Chapter 10, current national commitments under the Paris Agreement are not sufficient to keep warming below 2°C, and many issues remain regarding monitoring and reporting of reductions in emissions. However, as the first truly global agreement on climate change that commits countries to specific mitigation actions, the Paris Agreement provides a foundation for future progress.

Beyond these international agreements, significant efforts to mitigate emissions and combat climate change have already begun at a wide range of institutions, cities, states, and regions, which can act as living laboratories to test societal, governance, economic, and technical solutions. Lessons learned from these models can help guide the implementation of mitigation efforts at national and global scales.