宏观经济动态性视角下的环境政策选择——基于新凯恩斯DSGE模型的分析

Environmental Policy Choice Under the Perspective of Macroeconomic Dynamics:Based on the Analysis of the New Keynesian DSGE Model

空气污染已成为当前政府和公众面临的一个突出问题,选择并实施有效的环境政策是解决这一问题的关键。为此,本文通过引入空气污染排放变量和环境政策变量对经典的新凯恩斯DSGE模型进行拓展,基于拓展后的模型从经济增长和经济波动两个视角并结合数值求解法对限额排放、强度目标制以及污染排放税等三种环境政策进行比较分析。分析结果显示,在经济增长视角下,污染排放税政策优于限额排放和强度目标制政策;在减少经济波动视角下,限额排放政策应是优先选取的政策机制。与此同时,环境政策的选择还受经济中不确定因素来源的影响,当不确定因素来源于技术创新时,限额排放政策为优选政策;当不确定因素来源于政府消费支出或货币政策调控时,三种环境政策间无明显差异。政府应致力于将环境政策的制定和实施植入到整个宏观经济的发展中,考虑环境政策对经济增长和波动的影响,即环境政策实施的经济成本;做到环境政策决策基于宏观经济,根据不同的经济发展阶段、目标和现状恰当的选择环境政策工具,以优化环境政策实施效果。

Air pollution has become a prominent problem faced by the current government and the public,and the key to solve this problem is the selection and implementation of effective environmental polices. This paper,by introducing air pollution variables and environmental policy variables,expanded classic new Keynesian DSGE model,based on the expanded model from the perspective of both economic growth and economic fluctuations combined with numerical solution method to comparative analysis emissions cap policy,intensity target policy and emission tax policy. The results show that emission tax policy is better than emissions cap policy and intensity target policy in the perspective of economic growth; while,emissions cap policy should be a priority selection mechanism in the perspective of reducing economic fluctuations. Meanwhile,the choice of environmental policy is influenced by the source of uncertainty in the economy. When the uncertainty comes from the technology innovation,emissions cap policy is optimal policy; when the uncertainty comes from government spending or the monetary policy,there are no significant differences between these three types of environmental policy. The government should take the formulation and implementation of environmental policy under the whole macro economic development,considering the influence of environmental policy on economic growth and fluctuation,that is to say the economic costs of the implementation of environmental policy. Selecting environmental policy instruments correctly according to the stages,goals and status of the economic development,can optimize the effect of environment policy implementation.