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Climate change is regarded as one of the major factors enhancing the transmission intensity of dengue fever. In this study, we estimated the threshold effects of temperature on Aedes mosquito larval index as an early warning tool for dengue prevention. We also investigated the relationship between dengue vector index and dengue epidemics in Taiwan using weekly panel data for 17 counties from January 2012 to May 2019. To achieve our goals, we first applied the panel threshold regression technique to test for threshold effects and determine critical temperature values. Data were then further decomposed into different sets corresponding to different temperature regimes. Finally, negative binomial regression models were applied to assess the non-linear relationship between meteorological factors and Breteau index (BI). At the national level, we found that a 1&deg, C temperature increase caused the expected value of BI to increase by 0.09 units when the temperature is less than 27.21 &deg, C, and by 0.26 units when the temperature is greater than 27.21 &deg, C. At the regional level, the dengue vector index was more sensitive to temperature changes because double threshold effects were found in the southern Taiwan model. For southern Taiwan, as the temperature increased by 1&deg, C, the expected value of BI increased by 0.29, 0.63, and 1.49 units when the average temperature was less than 27.27 &deg, C, between 27.27 and 30.17 &deg, C, and higher than 30.17 &deg, C, respectively. In addition, the effects of precipitation and relative humidity on BI became stronger when the average temperature exceeded the thresholds. Regarding the impacts of climate change on BI, our results showed that the potential effects on BI range from 3.5 to 54.42% under alternative temperature scenarios. By combining threshold regression techniques with count data regression models, this study provides evidence of threshold effects between climate factors and the dengue vector index. The proposed threshold of temperature could be incorporated into the implementation of public health measures and risk prediction to prevent and control dengue fever in the future.

Pangolins are currently the most smuggled mammals in the world. Meanwhile, Taiwan has demonstrated the world’s first case of the use of artificial feeding to raise pangolins to adulthood. The government has also begun to cooperate with farmers in pangolin-spotted areas. Agricultural products can earn the green label once they have passed the evaluation. The challenge is that very few farms have obtained the pangolin-friendly label so far. Our hypothesis is that farmers lack the knowledge that consumers would pay additional money for products that are labeled pangolin-friendly compared to regular ones. Thus, farmers have an insufficient incentive to apply for this label. This research aims to fill this gap by providing people with the necessary knowledge. Contingent valuation with the single-bounded dichotomous choice format was used, which involved investigating 417 valid observations. We found the following: (1) customers are willing to pay about 8.06 USD for pangolin-friendly rice (an increase of 397% in relation to the mean price of rice), (2) customers are willing to pay for about 11.46 USD for pangolin-friendly tea (an increase of 179% in relation to the mean price of tea), and (3) customers are willing to pay about 25.81 USD for pangolin-friendly coffee (an increase of 509% in relation to the mean price of coffee). Our findings give farmers more incentive to conduct eco-friendly production. Consequently, the quality of agricultural products as well as the habitats of endangered pangolins improve. Thus, consumers’ health, the environment, and the future of pangolin conservation can benefit in this attempt to achieve sustainability.

Much energy-related construction causes environmental concern. Sometimes the environmental issue is so huge that it is difficult to make a policy decision even with the assistance of traditional valuation techniques. The third natural gas receiving station at Datan, Taiwan, is one example of this. The construction would be beneficial to energy security, economic development, and particulate matter (PM) 2.5 reduction. However, it would destroy a precious algal reef, which is a habitat for endangered species, biodiversity, and a unique ecological system. Thus, we used willingness-to-pay to show the strength of both pro-energy and pro-ecology opinions specifically to help with decision-making. First, respondents were asked to choose between the gas station and the reef. Then they were asked about their willingness to pay for that choice. We then estimated parametric/nonparametric models—traditional probit, structured probit, and Turnbull—to obtain reliable estimates. We found that the per-person value for pro-gas-station respondents was higher than that for pro-reef respondents, while the percentage of pro-reef respondents was higher than the percentage of pro-gas-station respondents. These results together form a clear policy implication for this case.

The main purpose of this study was to investigate how climate change affects blood vessel-related heart disease and hypertension and to estimate the associated economic damage. In this paper, both the panel data model and the contingent valuation method (CVM) approaches are applied. The empirical results indicate that the number of death from cardiovascular diseases would be increased by 0.226% as the variation in temperature increases by 1%. More importantly, the number of death from cardiovascular diseases would be increased by 1.2% to 4.1% under alternative IPCC climate change scenarios. The results from the CVM approach show that each person would be willing to pay US$51 to US$97 per year in order to avoid the increase in the mortality rate of cardiovascular diseases caused by climate change.