Many countries have carbon pricing in place, in the form of a tax and/or market. Generally, this involves low price rates, incomplete emissions coverage, and price reductions for particular sectors. This raises the question whether the label “carbon price” – in the environmental-economics textbook sense – really applies. To answer it, we assess the authenticity of 31 national carbon prices, calculating average carbon prices and their gap with advertised prices, at both national and sector levels. The results indicate a poor level of authenticity. This means that the carbon prices published by sources such as the World Bank provide a misleading representation of the actual national policy pressure on emissions. Countries show considerable differences regarding the average carbon price level and the gap with advertised prices. Moreover, there is not a one-to-one relationship between advertised and average carbon prices, suggesting the former are not a good basis for international comparison of policy effectiveness. Across countries, the mean carbon price equals €7.90/ton of CO₂ while the mean price gap is 57.7%. Most noticeably, the highest advertised price for Sweden should be interpreted with care as it goes along with a price gap of almost €100 to the average price. In addition, Switzerland and Finland show relatively high price gaps. To illustrate the relevance and non-triviality of our indicators, note that Sweden occupies a 3rd position in terms of average carbon price (after Norway and Switzerland), 27th in terms of price gap, and 16th in terms of effective rate (i.e. sum of implicit and explicit carbon prices). We further find that implicit carbon prices dominate explicit ones for most countries, notably in road transport, whereas the reverse holds for industrial and electricity sectors. Combining our findings with recent empirical evidence for carbon-pricing effectiveness highlights the potential of the instrument to combat climate change, provided implementation is improved and internationally harmonized. Shifting the attention from advertised to average carbon prices might help in this regard.

许多国家以税收和/或市场的形式制定了碳定价。一般而言，这涉及低价格率、不完全的排放覆盖以及特定行业的降价。这就提出了一个问题，即环境经济学教科书意义上的“碳价格”标签是否真的适用。为了回答这个问题，我们评估了 31 个国家碳价格的真实性，计算了国家和行业层面的平均碳价格及其与广告价格的差距。结果表明真实性较差。这意味着世界银行等来源公布的碳价格提供了对国家实际排放政策压力的误导性表述。各国在平均碳价格水平和与广告价格的差距方面表现出相当大的差异。而且，广告和平均碳价格之间不存在一对一的关系，这表明前者不是政策有效性国际比较的良好基础。在各国，平均碳价等于 7.90 欧元/吨 CO₂而平均价格差距为 57.7%。最值得注意的是，瑞典的最高广告价格应谨慎解读，因为它与平均价格相差近 100 欧元。此外，瑞士和芬兰的价格差距较大。为了说明我们指标的相关性和重要性，请注意瑞典在平均碳价格方面排名第三（仅次于挪威和瑞士），在价​​格差距方面排名第 27，在有效利率方面排名第 16（即总和隐性和显性碳价格）。我们进一步发现，对于大多数国家来说，隐性碳价格主导着显性碳价格，特别是在公路运输领域，而工业和电力部门则相反。将我们的发现与最近关于碳定价有效性的经验证据相结合，突出了该工具在应对气候变化方面的潜力，前提是改进实施并在国际上协调一致。将注意力从广告价格转移到平均碳价格可能在这方面有所帮助。