Emissions reduction has long been the most concerning environmental issue. To promote emissions reduction among firms, governments have adopted mandatory tools such as emissions tax and voluntary guidance such as government green publicity. This paper investigates the interaction between emissions tax and government green publicity and analyzes the optimal decisions when the government combines these two policies. The results show that these two policies are mutually reinforcing, that is, the enhancement of one leads to the enhancement of the other. Moreover, although these two policies are complements in reducing emissions, it may be not wise to combine them to improve social welfare. Specifically, when the emissions damage is small, these two policies are substitutes in improving social welfare. More surprisingly, this substitutive relationship will increase with the baseline emissions level. This suggests that governments combining these two policies may not suitable for addressing high-pollution industries. When governments combine these two policies, intuitively, the emissions tax level and publicity degree will increase with tax implement efficiency. However, the results show that when the emissions damage is relatively large, the emissions tax level and publicity degree will decrease with tax efficiency. We also find that under asymmetric firms, heightened competition will improve the social welfare and the strategic complementarity of the two policies, albeit at the cost of firms’ profits. Moreover, we analyze the influence of budget constraints, revealing that as the budget limit level decreases, the strategic complementarity can initially decline but subsequently exhibit an upward trend.

中文翻译：

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两条线工作？政府绿色宣传与排污税的关系

减排一直是最受关注的环境问题。为了促进企业减排，政府采取了排污税等强制性工具和政府绿色宣传等自愿性指导手段。本文研究了排污税与政府绿色宣传之间的相互作用，并分析了政府结合这两种政策时的最优决策。结果表明，这两项政策是相辅相成的，即一项政策的增强会导致另一项政策的增强。此外，虽然这两项政策在减排方面是互补的，但将它们结合起来来改善社会福利可能并不明智。具体来说，当排放损害较小时，这两项政策在改善社会福利方面具有替代性。更令人惊讶的是，这种替代关系将随着基线排放水平的增加而增强。这表明政府结合这两项政策可能不适合解决高污染行业问题。当政府将这两项政策结合起来时，直观地看，排污税水平和宣传程度将随着税收实施效率的提高而提高。但研究结果表明，当排放损害较大时，排污税水平和宣传程度会随着税收效率的提高而降低。我们还发现，在不对称企业下，竞争的加剧将改善社会福利和两种政策的战略互补性，尽管是以企业利润为代价的。此外，我们分析了预算约束的影响，发现随着预算限额水平的降低，战略互补性最初会下降，但随后呈现上升趋势。