5 Items

Report - Harvard Project on Climate Agreements

Governance of the Deployment of Solar Geoengineering

The Harvard Project on Climate Agreements has released a volume of 26 briefs that explores a range of topics related to how we might govern the deployment of solar geoengineering.

View of the crescent moon through the top of the earth's atmosphere. Photographed above 21.5°N, 113.3°E by International Space Station crew Expedition 13 over the South China Sea, just south of Macau (NASA image ID: ISS013-E-54329).

NASA

Discussion Paper

Governance of Highly Decentralized Nonstate Actors: the Case of Solar Geoengineering

| November 2018

We here introduce the idea of highly decentralized solar geoengineering, plausibly done in form of small high-altitude balloons. While solar geoengineering has the potential to greatly reduce climate change, it has generally been conceived as centralized and state deployed. Potential highly decentralized deployment moves the activity from the already contested arena of state action to that of environmentally motivated nongovernmental organizations and individuals, which could disrupt international relations and pose novel challenges for technology and environmental policy. We explore its feasibility, political implications, and governance.

Discussion Paper - Harvard Project on Climate Agreements

An Economic Anatomy of Optimal Climate Policy

| August 2018

The authors introduce geoengineering into an optimal control model of climate economics. Together with mitigation and adaptation, carbon and solar geoengineering span all possible climate policies. Their wildly different characteristics have important implications for policy. They show in the context of their model that: (i) whether emissions are positive or zero the optimal carbon tax always equals the marginal cost of carbon geoengineering; (ii) the introduction of either form of geoengineering leads to higher emissions yet lower temperatures; (iii) in a world with above-optimal cumulative emissions, mitigation alone is insufficient and only a complete set of instruments can minimize climate damages.

This is an updated version of a paper first published in July 2017.

Discussion Paper - Harvard Project on Climate Agreements, Belfer Center

Confronting Deep and Persistent Climate Uncertainty

| July 2016

Estimates of damages from climate change are dependent on estimates of global-average-temperature increase, which in turn depend on how marginal increases in greenhouse-gas concentrations affect temperature. The "likely" range of temperature increase from a doubling of concentrations has stalled for 35 years at 1.5–4.5° C—making estimates of damages difficult and unreliable.

Discussion Paper - Harvard Project on Climate Agreements, Belfer Center

Climate Sensitivity Uncertainty: When is Good News Bad?

| September 2015

Uncertainty about "climate sensitivity"—the impact on temperature of increased concentrations of greenhouse gases—grew from the IPCC's 4th to 5th Assessment Reports. The authors conclude that this "bad news" outweighs the "good news": a lower value for the bottom end of the range for temperature rise.