标题：Does a Warm Spell Influence Public Attitudes about Assisting Farmers in Climate Change Adaptation Policies? Evidence from a Natural Experiment from Michigan
摘要：While policies for responding climate change impacts need the support and cooperation from the public who may be affected by the policies, understanding the general public’s opinion is important and can help form feasible action plans. In this paper we take advantage of a temperature event that took place during primary data collection to explore how this affects public opinion about helping farmers adapt to climate change. We find that the public is surprisingly supportive of government involvement in farmer adaptation, and that the warm spell has a brief positive effect on support. For several years until 2011, there was a trend of declining belief in the existence and seriousness of climate change. In 2012, belief in climate change bounced back and meanwhile for several months in that year the monthly average temperatures were record highs. While it is reasonable to hypothesize that contemporaneous weather may influence the public’s attitudes about addressing climate change issues, it is unclear how temperature affects public attitudes. There are gaps in existing research about the determinants of public attitudes towards climate change. How public attitudes towards adaptation policy, especially with respect to a government’s intervention aimed at improving prospects for a particular industry sector, is influenced under unusual weather events, are rarely discussed. Until very recently, researchers have not explored how public opinion is influenced by climate change phenomenon per se, especially periods abnormally warm temperature. Prior articles discuss the effect of temperature with certain limitations, including perception of temperature rather than actual temperature, general temperature rather than deviations from normal status, and either short run or relatively long run average temperature to represent the temperature when the survey was taken rather than the temperature of the day when the respondent answered the survey. Another missing issue among climate change surveys is the public’s opinion on adaptation policies, although many have discussed ideas surrounding that of mitigation policies. As Palutikof, Agnew and Hoar indicated in their work, “…none of these studies addressed people’s responses and adaptations.” How the general public thinks about adaptation strategies and policies is seldom considered. Similar to studies about public opinion, we found little research regarding how willingness to pay (WTP) for adaptation policies or strategies is influenced by specific climate change phenomenon. None of the research considered the WTP for an adaptation policy in reference to a particular industry or addressed the effect of abnormal warm temperature. Since agriculture is likely to be one of the most affected industries under climate change, with potentially serious global food availability issues if climate change outpaces the rate of adaptation, understanding public support for government involvement in adaptation and the public’s WTP to fund such efforts can inform policy dialogue about these critical questions. Therefore, we focus on adaptation in agriculture to explore public opinion toward government involvement in helping the sector adapt as well as the WTP for an adaptation policy. We use the data based on a random sample general population poll in Michigan, secondary sources, and an unseasonal fruit-crop damaging warm spell that occurred during the survey period to assess the effects of this short-term phenomenon on public attitudes and the WTP. Temperatures during the two-week warm spell went as high as 40° F above normal Considered as a natural experiment, this unexpected warm spell provided variation of daily temperature deviation and variation of the exposure of this abnormal temperature when respondents were surveyed. Thus, in addition to the daily temperature deviation, as well as its accumulation for a short period (3 days, a week, etc.), several time period index variables are used to explore how the level of the respondents’ exposure to the warm spell would affect the attitudes and WTP. The basic set up is before-within-after warm spell, and we test several variations of time modeling approaches to explore the duration of the effect. Demographic variables and political ideology are used to control selection bias. While it is unable to control in our data set, we consider the effect due to media coverage of the warm spell as an indirect effect and part of the priming mechanism. We constructed four questions to understand how attitudes about government adaptation assistance vary across levels of government (state or national) and crop types (corn-soybeans or fruits-vegetables) since climate change is an issue which has national and worldwide impacts but agricultural production techniques are more localized. In addition to the questions about government assistance, the instrument also included single-bounded dichotomous choice questions to evaluate the WTP for government-sponsored adaptation programs. Given the contentious nature of climate change, it was surprising to find that around two thirds of the respondents showed a tendency to support the idea of the governments’ role helping farmers of either corn/soybeans or fruit/vegetables adjust their cropping systems. This could be due to the warm spell or the fact that we focus on agriculture, where the public may more easily connect changes in weather with the need to adapt than might be the case with other sectors. Results from the basic models confirm several of our hypotheses. Abnormally warm temperature deviation does affect the public attitude toward government’s role on adaptation significantly. So does the variables of sub-periods or exposure of warm spell. However, the WTP is only affected significantly by these time period index variables while the temperature deviation is not significant. In other words, there appears to be a kind of tipping point beyond which further increases in deviation do not make much difference. From the preliminary results, we found that, the public attitudes about whether government should be involved in the adaptation are quite sensitive to short run temperature anomalies. The warm spell effect boosted the support, but it did not last long and quickly dropped back to the pre-event level or lower level merely on the second week of the warm spell. In addition, temperature anomalies may lead to more polarized public attitudes. We also found that the support is higher while the question specified the agriculture industry than in the general question without mentioning specific industry. The importance of local agriculture production had certain but more muted influence than our a priori expectations. Our research focuses on the agriculture industry, adaptation policies, as well as the WTP. The three key dimensions distinguish this paper from prior work. Our research further identifies the effect of the unusual warm spell event by various means. This paper shows how the warm spell event influenced the public attitudes toward climate change adaptation policy regarding two government levels and two crop types and the WTP for government-sponsored adaptation programs. The effects of daily or cumulated temperature deviation as well as the level of exposure to the warm spell will be discussed.
