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<p>Concentrations of atmospheric methane (<span class="inline-formula">CH₄</span>), the second most important greenhouse gas, continue to grow. In recent years this growth rate has increased further (2020: <span class="inline-formula">+15.6</span> ppb), the cause of which remains largely unknown. Here, we demonstrate a high-resolution (<span class="inline-formula">∼80</span> km), short-window (24 h) 4D-Var global inversion system based on the ECMWF Integrated Forecasting System (IFS) and newly available satellite observations. The largest national disagreement found between prior (5.3 Tg per month) and posterior (5.0 Tg per month) <span class="inline-formula">CH₄</span> emissions is from China, mainly attributed to the energy sector. Emissions estimated from our global system are in good agreement with those of previous regional studies and point source-specific studies. Emission events (leaks or blowouts) <span class="inline-formula">&gt;</span> 10 t <span class="inline-formula">CH₄</span> h<span class="inline-formula">⁻¹</span> were detected, but without appropriate prior uncertainty information, were not well quantified. Our results suggest that global anthropogenic <span class="inline-formula">CH₄</span> emissions for the first 6 months of 2020 were, on average, 470 Gg per month (<span class="inline-formula">+1.6</span> %) higher than for 2019, mainly attributed to the energy and agricultural sectors. Regionally, the largest increases were seen from China (<span class="inline-formula">+220</span> Gg per month, 4.3 %), with smaller increases from India (<span class="inline-formula">+50</span> Gg per month, 1.5 %) and the USA (<span class="inline-formula">+40</span> Gg per month, 2.2 %). When assuming a consistent year-on-year positive trend in emissions, results show that during the onset of the global slowdown (March–April 2020) energy sector <span class="inline-formula">CH₄</span> emissions from China increased above expected levels; however, during later months (May–June 2020) emissions decreased below expected levels. Results for the first 6 months of 2019/20 suggest that the accumulated impact of the COVID-19 slowdown on <span class="inline-formula">CH₄</span> emissions from March–June 2020 might be small relative to the long-term positive trend in emissions. Changes in OH concentration, not investigated here, may have contributed to the observed growth in 2020.</p>