UC San Diego

This dissertation is composed of three original, self- contained essays on environment and development economics. In the first essay we examine the relationship between weather and rice production at the farm level in Asia. Higher minimum temperature reduced yield while higher maximum temperature raised it; radiation's impact varied by growth phase. Combined, these effects imply that yield at most sites would have grown more rapidly during the high-yielding season but less rapidly during the low- yielding season if observed temperature trends at the end of the 20th Century had not occurred. Diurnal temperature variation must be considered when investigating the impacts of climate change on irrigated rice in Asia. In the second essay, I expand on the models used in the first, and incorporate the fact that agricultural yield functions are non-linear, with sharp negative impacts when crops are exposed to temperature in excess of certain thresholds. Exploiting exogenous variation in planting date, I demonstrate exogenous variation in above-threshold exposure-time comparable to the projected increase due to 100 years of climate change, and analyze the ability of farmers to make adjustments to compensate. I show that farmers do make small adjustments in the quantity of seed that they plant, as well as the amount of nitrogen fertilizer that they apply to the crop. This has important implications for the validity of the typical approach of using observed weather shocks to measure the impact of climate change on agriculture : farmers make adjustments according to expectations. As climate change will be slow and predictable, measuring agricultural output as a function of unpredictable shocks may overstate the true impact of climate change. The third essay is unrelated to the first two, and in it we study the consequences of poverty alleviation programs for environmental degradation. We exploit the community-level eligibility discontinuity for a conditional cash transfer program in Mexico to identify the impacts of income increases on deforestation, and use the program's initial randomized rollout to explore household responses. We find that additional income raises consumption of land-intensive goods and increases deforestation. The observed production response and deforestation increase are larger in communities with poor road infrastructure. This suggests that better access to markets disperses environmental harm and that the full effects of poverty alleviation can be observed only where poor infrastructure localizes them