This study investigates the effects of climatic variations and extremes captured by variability in temperature, precipitation, and incidents of typhoons on aggregate inter-provincial migration within ...the Philippines using panel data. Our results indicate that a rise in temperature and to some extent increased typhoon activity increase outmigration, while precipitation does not have a consistent, significant effect. We also find that temperature and typhoons have significant negative effects on rice yields, a proxy for agricultural productivity, and generate more outmigration from provinces that are more agriculturally dependent and have a larger share of rural population. Finally, migration decisions of males, younger individuals, and those with higher levels of education are more sensitive to rising temperature and typhoons. We conclude that temperature increase and to some extent typhoon activities promote migration, potentially through their negative effect on crop yields. The migration responses of males, more educated, and younger individuals are more sensitive to these climatic impacts.
Researchers have extensively studied crop yield response to weather variations, while only a limited number of studies have attempted to identify spatial heterogeneity in this relationship. We ...explore spatial heterogeneity in corn yield response to weather by combining geographically weighted regression and panel regression. We find that temperature tends to have negative effects on U.S. corn yields in warmer regions and positive effects in cooler regions, with spatial heterogeneity at a fine scale. The spatial pattern of precipitation effects is more complicated. A further analysis shows that precipitation effects are sensitive to the existence of irrigation systems.
While there is considerable interest in understanding the climate–migration relationship, particularly in the context of concerns about global climatic change, little is known about its underlying ...mechanisms. In the paper, we combine a rich panel data on annual bilateral international migration flows with an extensive data on climate variability across the countries to investigate in-depth the climate–migration link. We find a positive and statistically significant relationship between temperature and international outmigration only in the most agriculture-dependent countries, consistent with the widely documented adverse impact of temperature on agricultural productivity. Further, the temperature–migration relationship is nonlinear and resembles the nonlinear temperature–yield relationship. In addition, migration flows to current major destinations are especially temperature-sensitive. Policies to address issues related to climate-induced international migration would be more efficient if focused on the agriculture-dependent countries and especially people in those countries whose livelihoods depend on agriculture.
•We examine the relationship between climate variability and international migration.•We use an annual bilateral international migration data set for 1980–2010.•Temperature induces international outmigration only from agricultural countries.•Migration flows to current major destinations are especially temperature-sensitive.
Technologies and management practices (TMPs) that reduce the application of nitrogen (N) fertilizer while maintaining crop yields can improve N use efficiency (NUE) and are important tools for ...meeting the dual challenges of increasing food production and reducing N pollution. However, because farmers operate to maximize their profits, incentives to implement TMPs are limited, and TMP implementation will not always reduce N pollution. Therefore, we have developed the NUE Economic and Environmental impact analytical framework (NUE3) to examine the economic and environmental consequences of implementing TMPs in agriculture, with a specific focus on farmer profits, N fertilizer consumption, N losses, and cropland demand. Our analytical analyses show that impact of TMPs on farmers’ economic decision‐making and the environment is affected by how TMPs change the yield ceiling and the N fertilization rate at the ceiling and by how the prices of TMPs, fertilizer, and crops vary. Technologies and management practices that increase the yield ceiling appear to create a greater economic incentive for farmers than TMPs that do not but may result in higher N application rates and excess N losses. Nevertheless, the negative environmental impacts of certain TMPs could be avoided if their price stays within a range determined by TMP yield response, fertilizer price, and crop price. We use a case study on corn production in the midwestern United States to demonstrate how NUE3 can be applied to farmers’ economic decision‐making and policy analysis. Our NUE3 framework provides an important tool for policymakers to understand how combinations of fertilizer, crop, and TMP prices affect the possibility of achieving win‐win outcomes for farmers and the environment.
Previous research on the determinants of international migration has largely focused on objective factors, such as income. We instead use subjective well-being (SWB) to explain international ...migration desires, an expressed willingness to migrate. We find that individuals with higher SWB have lower international migration desires. At the individual level, the SWB-migration relationship appears to be more robust than the income-migration relationship. At the country level, national average SWB better indicates international migration desires for rich countries, while income performs better for poor countries. We thus demonstrate the feasibility of employing subjective measures to study at least one aspect of an important social outcome, migration.
► A dynamic optimal model for crop rotation is developed. ► The Bellman equation is used to optimize crop rotation decisions. ► Crop rotation scheme is unlikely for extreme high or low corn prices. ► ...Producers prefer crop rotation scheme when yield penalty is high. ► Multi-year effects enforce larger planting constraint compared to 1-year effect.
A dynamic optimization model is developed to show how crop yield and price volatility could impact acreage response under crop rotation considerations. By maximizing net present value of expected current and future farm profits, a modified Bellman equation helps optimize planting decisions. Our model is capable of simulating crop rotations with different lengths and structures. The corn–soybean rotation was simulated using the model to determine break-even prices for alternative planting decisions. Furthermore, we assume that the extent to which crop yields are penalized when skipping a rotation scheme is not fixed. Then we investigated the relationship between yield penalty levels and break-even corn price percentage changes. By considering both 1-year and 2-year carry-over effects which represent how previous crops affect current crop yield, our results indicate that producers are more likely to choose a crop rotation scheme when yield penalties are higher.
A dynamic optimization model is developed to show how crop yield and price volatility could impact acreage response under crop rotation considerations. By maximizing net present value of expected ...current and future farm profits, a modified Bellman equation helps optimize planting decisions. Our model is capable of simulating crop rotations with different lengths and structures. The cornasoybean rotation was simulated using the model to determine break-even prices for alternative planting decisions. Furthermore, we assume that the extent to which crop yields are penalized when skipping a rotation scheme is not fixed. Then we investigated the relationship between yield penalty levels and break-even corn price percentage changes. By considering both 1-year and 2-year carry-over effects which represent how previous crops affect current crop yield, our results indicate that producers are more likely to choose a crop rotation scheme when yield penalties are higher.
Future climate change will likely to increase the frequency and severity of droughts in many regions of the U.S., especially in the southwestern states, thus further will reduce the water supply in ...those states. On the water demand side, the population of the U.S. also moves to the southwestern states (both domestic and international migrants). Coupling the projections of water supply and demand, we generate the relative water stress index for the contiguous U.S. counties for the years 2020, 2030, 2040, and 2050. We find a worsening water stress situation, especially in the western U.S. Meanwhile, we find that some metropolitan areas in the east may also have severe water stress despite good water supply.
Using principal component analysis, a climate index is developed to estimate the linkage between climate and crop yields. The indices based on three climate projections are then applied to forecast ...future crop yield responses. We identify spatial heterogeneity of crop yield responses to future climate change across a number of U.S. northern and southern states. The results indicate that future hotter/drier weather conditions will likely have significant negative impacts on southern states, whereas only mild impacts are expected in most northern states.
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