Countries by Methane (CH4) emissions from Transport (Energy) (Mt CO2e)
China leads all 194 countries in methane emissions from transport with 5.542 Mt CO2e, followed by the United States at 3.5925 Mt CO2e and Iran at 2.6688 Mt CO2e. At the other end of the ranking, Kiribati, Dominica, and the British Virgin Islands each record just 0.0001 Mt CO2e. The gap between the top and bottom of the ranking spans more than 5.5 million percent, reflecting the vast differences in fleet size, fuel type, and transport activity across economies.
Ranking 2024
Analysis
This metric measures annual methane (CH4) emissions from the transportation sector, expressed in megatonnes of carbon dioxide equivalent (Mt CO2e) using AR5 global warming potentials. The source definition covers emissions from IPCC 2006 codes 1.A.3.a Civil Aviation, 1.A.3.b_noRES Road Transportation no resuspension, 1.A.3.c Railways, 1.A.3.d Water-borne Navigation, and 1.A.3.e Other Transportation. The metric is standardized to carbon dioxide equivalent value. Data come from the World Bank World Development Indicators, indicator code EN.GHG.CH4.TR.MT.CE.AR5, for the year 2024. Coverage is 194 countries, all with data from the last seven years, and 100% of data points are classified as official quality. The viability checks identified 38 extreme outliers at the 3-sigma threshold, and the range runs from 0.00 to 5.54 Mt CO2e, a spread of 5,541,900%.
The top of the ranking is dominated by large, high-population countries with extensive road and aviation networks. China (rank 1) records 5.542 Mt CO2e, more than 1.9 Mt CO2e above the United States (rank 2, 3.5925 Mt CO2e). Iran (rank 3, 2.6688 Mt CO2e) and India (rank 4, 2.4049 Mt CO2e) follow closely, with the Russian Federation (rank 5, 1.0017 Mt CO2e) the only other country exceeding 1 Mt CO2e. Indonesia (rank 6, 0.916), Brazil (rank 7, 0.7906), and Mexico (rank 8, 0.6771) round out the upper tier. Canada (rank 9, 0.5773) and Nigeria (rank 10, 0.5526) complete the top ten, showing that both high-income and large developing economies appear near the top.
The middle of the ranking shows notable placements. Libya ranks 24th at 0.2146 Mt CO2e, placing it above Germany (rank 25, 0.1987) and Australia (rank 26, 0.1978), and close to South Korea (rank 22, 0.2291). Uzbekistan ranks 32nd at 0.1706, ahead of Spain (rank 33, 0.1597). In the lower half, Benin (rank 65, 0.0384) slightly exceeds Belgium (rank 66, 0.0383), and Denmark and North Korea are tied at rank 106 with identical values of 0.014 Mt CO2e. Niger and Yemen are also tied at rank 119 with 0.01 Mt CO2e each. Several small island states and territories cluster at the very bottom, with values at or near 0.0001 Mt CO2e.
Several data limitations apply to this metric. Methane emissions from transport are generally small relative to CO2 from the same sector, and measurement methodologies can vary by country, particularly for road transport and water-borne navigation. The metric excludes resuspension effects from road transport, as indicated by the IPCC code 1.A.3.b_noRES designation. Territories and special administrative regions such as Puerto Rico (US), Hong Kong SAR, Macao SAR, Greenland, New Caledonia, French Polynesia, Aruba, Gibraltar, Cayman Islands, Bermuda, British Virgin Islands, and Turks and Caicos Islands are included in the 194-country count, which may affect comparisons with sovereign nation rankings. The 38 extreme outliers identified at the 3-sigma threshold suggest the distribution is heavily skewed by the top-ranked countries, and small differences in the lower ranks may not be statistically meaningful.
Methodology
Data are drawn from the World Bank World Development Indicators, indicator code EN.GHG.CH4.TR.MT.CE.AR5, for the reference year 2024. The metric covers annual methane (CH4) emissions from the transportation sector, including IPCC 2006 codes 1.A.3.a Civil Aviation, 1.A.3.b_noRES Road Transportation no resuspension, 1.A.3.c Railways, 1.A.3.d Water-borne Navigation, and 1.A.3.e Other Transportation. The measure is standardized to carbon dioxide equivalent value using AR5 global warming potentials. The ranking covers 194 countries, all of which have data from within the last seven years (100% recency). All 194 data points are classified as official quality (100%). The viability checks flagged 38 extreme outliers at the 3-sigma threshold. The data range runs from 0.00 to 5.54 Mt CO2e, representing a spread of 5,541,900%. Average year-over-year change across the dataset is 8.0%, within the 50% volatility threshold. Territories and special administrative regions are included in the country count.