Modeling adaptation as a flow and stock decision with mitigation

An effective policy response to climate change will include, among other things, investments in lowering greenhouse gas emissions (mitigation), as well as short-term temporary (flow) and long-lived capital-intensive (stock) adaptation to climate change. A critical near-term question is how investments in reducing climate damages should be allocated across these elements of a climate policy portfolio, especially in the face of uncertainty in both future climate damages and also the effectiveness of yet-untested adaptation efforts. We build on recent efforts in DICE-based integrated assessment modeling approaches that include two types of adaptation—short-lived flow spending and long-lived depreciable adaptation stock investments—along with mitigation, and we identify and explore the uncertainties that impact the relative proportions of policies within a response portfolio. We demonstrate that the relative ratio of flow adaptation, stock adaptation, and mitigation depend critically on interactions among: 1) the relative effectiveness in the baseline of stock versus flow adaptation, 2) the degree of substitutability between stock and flow adaptation types, and 3) whether there exist physical limits on the amount of damages that can be reduced by flow-type adaptation investments. The results indicate where more empirical research on adaptation could focus to best inform near-term policy decisions, and provide a first step towards considering near-term policies that are flexible in the face of uncertainty

Prevention and protection: the simultaneous implementation of climate change mitigation and adaptation policies

Mitigation and adaptation are the two key responses available to policymakers to reduce the risks of climate change. This three-essay dissertation is motivated by the fact that no coherent or policy-relevant understanding yet exists for how adaptation should be integrated into an overall understanding of the climate problem, or how policymakers can appropriately view mitigation and adaptation tradeoffs for decision making. The research goal is to frame and conceptualize these tradeoffs in joint implementation for decision makers in a way that is useful for understanding policy. My hypothesis is that in order to achieve this goal, emphasis should be given to two key strategy characteristics that most inform the relevant relationships and tradeoffs that occur when mitigation and adaptation are considered together. The framework development of the first essay finds that mitigation and adaptation tradeoffs are most apparent to policymakers if the strategies are compared on their investment lifetimes and strategy limits, in relation to climate damages, as well as how they both behave under uncertainty. Because of these two fundamental differences in strategies, adaptation is more usefully thought of as a portfolio of distinct investment types with different lifetimes and design capacity ranges for different damage sectors. Three distinct classes of adaptation activities can be created as a simplifying construct for policy analysis: flexible and short-lived flow spending, committed and long-lived new stock investments, and retrofitting of pre-existing adaptation stock investments. These adaptation types can be integrated with mitigation into an explicit decision analysis framework in order to explore the optimal portfolio of mitigation and different adaptation responses over time. In the second essay this framework is incorporated into a new DICE-based integrated assessment model that characterizes adaptation to climate change as either short-lived flow spending or long-lived adaptation stock investments. In the third essay I examine the extent to which the design of the policy mechanism for raising and distributing international adaptation financing as part of a global climate change regime affects participation in and compliance with such a treaty, and thus the emergence of such a successful agreement

Solar Radiation Modification is risky, but so is rejecting it : A call for balanced research

As it is increasingly uncertain whether humanity can limit global warming to 1.5 degrees, Solar Radiation Modification (SRM) has been suggested as a potential temporary complement to mitigation. While no replacement for mitigation, evidence to date suggests that some SRM methods could contribute to reducing climate risks and would be technically feasible. But such interventions would also pose environmental risks and unprecedented governance challenges. The risks of SRM must be carefully weighed against those of climate change without SRM. Currently, both types of risks are not sufficiently understood to assess whether SRM could be largely beneficial. Given the already serious impacts of climate change and the possibility that pressure from their increasing severity will trigger rash decisions, we argue that timely, careful investigation and deliberation on SRM is a safer path than wilful ignorance. A framework of ethical guidelines and regulation can help limit potential risks from SRM research

The Evolving International Climate Change Regime: Mitigation, Adaptation, Reflection

The complex international regime for climate change has evolved over the past three decades, from the Framework Convention on Climate Change and the Kyoto Protocol through the Paris Agreement and beyond. We assess this evolution from the 1990s to the 2020s, and its potential future evolution from the 2020s to the 2050s, across three main policy strategies: mitigation, adaptation, and reflection. In its first three decades, the regime has focused predominantly on the mitigation of net emissions and on engaging all major emitting countries in that effort. More recently, as progress on mitigation has been slow and as the impacts of climate change have risen around the world, the regime has begun to address adaptation. The next three decades may see the rise of a third strategy, reflection, if actors (collectively or unilaterally) perceive an urgent need to alleviate peak climate damages through fast-acting but controversial and risky climate interventions known as sunlight reflection methods or solar radiation modification (SRM). Several major international groups have recently issued reports on SRM, yet the international climate change regime has not yet constructed a governance regime for assessment or management of SRM. We recommend and outline comprehensive risk-risk tradeoff analyses of SRM to help avoid harmful countervailing risks. We suggest the development of an adaptive governance regime, starting early and embracing iterative and inclusive learning and updating over time. We urge that among the first key steps should be the development of a transparent international monitoring system for SRM. Such a monitoring system could provide early warning and help deter any unilateral SRM, assess the intended and unintended global and regional impacts of any research or eventual deployment of SRM, foster collective deliberation and reduce the risk of international conflict over SRM, help attribute adverse side effects of SRM to assist those adversely affected, and aid learning to improve the system adaptively over time. Thus, any reflection (of sunlight) should involve ongoing reflection (analysis and revision). Such an SRM monitoring regime is needed before SRM might be deployed, and can be developed at the same time that the focus of current efforts remains on mitigation and adaptation

Solar radiation modification is risky, but so is rejecting it: a call for balanced research

Ethics & Philosophy of TechnologyGeoscience and Remote Sensin