Solar geoengineering may lead to excessive cooling and high strategic uncertainty.

Climate engineering-the deliberate large-scale manipulation of the Earth's climate system-is a set of technologies for reducing climate-change impacts and risks. It is controversial and raises novel governance challenges [T. C. Schelling, Climatic Change, 33, 303-307 (1996); J. Virgoe, Climatic Change, 95, 103-119 (2008)]. We focus on the strategic implications of solar geoengineering. When countries engineer the climate, conflict can arise because different countries might prefer different temperatures. This would result in too much geoengineering: the country with the highest preference for geoengineering cools the planet beyond what is socially optimal at the expense of the others-a theoretical possibility termed "free-driving" [M. L. Weitzman, Scand. J. Econ., 117, 1049-1068 (2015)]. This study is an empirical test of this hypothesis. We carry out an economic laboratory experiment based on a public "good or bad" game. We find compelling evidence of free-driving: global geoengineering exceeds the socially efficient level and leads to welfare losses. We also evaluate the possibility of counteracting the geoengineering efforts of others. Results show that countergeoengineering generates high payoff inequality as well as heavy welfare losses, resulting from both strategic and behavioral factors. Finally, we compare strategic behavior in bilateral and multilateral settings. We find that welfare deteriorates even more under multilateralism when countergeoengineering is a possibility. These results have general implications for governing global good or bad commons.

Data on how abundance of resource inflows and punishment types affect resource extraction behavior.

The data is collected through laboratory experiments on a dynamic common pool resource game, where, in an infinitely repeated number of rounds (i.e., game ended randomly), individuals made decisions about whether to exert a high or a low effort level to extract resources. Experiments were conducted using the student sample (consent provided and ethics approved) at the University of Hawai'i at Manoa. A total of 8 sessions, 2 for each of the 4 treatments, were run with exactly 20 participants within a session. Individuals made decisions in groups of 10. Communication between any participant was not allowed. A session is randomly assigned (1) to vary whether the inflow of resources at the beginning of each round is high or low, and (2) to allow participants to either financially punish or socially punish defectors. A financial punishment resulted to a loss in profit for the punished while a social punishment displayed the words "You have extracted too much! You're being greedy!" on the computer screen of the punished. Individuals were assigned subject ID numbers and interacted using their subject IDs. The data is useful in understanding how resource inflow and type of punishment affects individual resource extraction behavior. The data could also be combined with other publicly available common pool resource datasets for a meta-analysis on individual behavior in the commons.

Data on transnational ecological compensation under a 'no net loss' biodiversity policy.

We conducted surveys in Denmark, Spain, and Ghana to solicit individual preferences for national and international ecological compensation for forest cover lost in the participant's home country due to the construction of a road. In the same survey, we also solicited individual socio-demographic characteristics and preferences, such as their gender, their risk preferences, whether they think individuals in Denmark, Spain, or Ghana can be trusted, etc. The data is useful for understanding individual preferences for national and international ecological compensation under a net outcomes type biodiversity policy (e.g., "no net loss"). It can also be used to understand how individual preferences and socio-demographic characteristics can be used to understand an individual's choice for ecological compensation.

Data on donation behavior towards the conservation of migratory species.

The data contains 716 individual decisions and responses from a lab-in-field experiment and an exit questionnaire that were conducted in Denmark, Spain, and Ghana. Individuals were initially asked to perform a small effort task (i.e., correctly counting the number of 1's and 0's in a page) to earn money and subsequently asked how much of their earnings they were willing to donate to BirdLife International to conserve Danish, Spanish, and Ghanaian habitats of the Montagu's Harrier, a migratory bird. The data is useful in understanding individual willingness-to-pay to conserve the habitats of the Montagu's Harrier along its flyway and could aid policymakers in having a clearer and more complete idea of support for international conservation. Among other things, the data can be used to look at the effect of individual socio-demographic characteristics and environmental and donation preferences on actual donation behavior.

One-shot exogenous interventions increase subsequent coordination in Denmark, Spain and Ghana.

Everyday, we are bombarded with periodic, exogenous appeals and instructions on how to behave. How do these appeals and instructions affect subsequent coordination? Using experimental methods, we investigate how a one-time exogenous instruction affects subsequent coordination among individuals in a lab. Participants play a minimum effort game repeated 5 times under fixed matching with a one-time behavioral instruction in either the first or second round. Since coordination behavior may vary across countries, we run experiments in Denmark, Spain and Ghana, and map cross-country rankings in coordination with known national measures of fractualization, uncertainty avoidance and long-term orientation. Our results show that exogenous interventions increase subsequent coordination, with earlier interventions yielding better coordination than later interventions. We also find that cross-country rankings in coordination map with published national measures of fractualization, uncertainty avoidance, and long-term orientation.