The international response to climate change has been inadequate, but not zero. There are 1,800 climate change laws worldwide. We use panel data on legislative activity in 133 countries over the period 1999–2016 to identify statistically the short-term and long-term impact of climate legislation. Each new law reduces annual carbon dioxide (CO₂) emissions per unit of gross domestic product by 0.78% nationally in the short term (during the first three years) and by 1.79% in the long term (beyond three years). The results are driven by parliamentary acts and by countries with a strong rule of law. In 2016, current climate laws were associated with an annual reduction in global CO₂ emissions of 5.9 GtCO₂, more than the US CO₂ output that year. Cumulative CO₂ emissions savings from 1999 to 2016 amount to 38 GtCO₂, or one year’s worth of global CO₂ output. The impact on other greenhouse gases is much lower.

国际上对气候变化的反应还不够，但不是零。全球有1,800项气候变化法律。我们使用有关1999-2016年间133个国家中立法活动的面板数据，从统计学上确定气候立法的短期和长期影响。每项新法律在短期内（头三年）在全国范围内将单位国内生产总值的年度二氧化碳（CO ₂）排放量降低了0.78％，而在长期内（三年后）则降低了1.79％。结果是由议会法案和拥有强大法治的国家推动的。2016年，当前的气候法与每年减少5.9 GtCO _2的全球CO ₂排放量相关，超过美国的CO ₂排放量当年的输出。从1999年到2016年，CO ₂累计节省的排放量达到38 GtCO ₂，相当于一年全球CO ₂排放量。对其他温室气体的影响要低得多。