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<p>The Canadian Arctic (&gt;&thinsp;60<span class="inline-formula">^∘</span>&thinsp;N, 60–141<span class="inline-formula">^∘</span>&thinsp;W) may undergo drastic changes if the Arctic warming trend continues. For methane (<span class="inline-formula">CH₄</span>), Arctic reservoirs are large and widespread, and the climate feedbacks from such changes may be potentially substantial. Current bottom-up and top-down estimates of the regional <span class="inline-formula">CH₄</span> flux range widely. This study analyzes the recent observations of atmospheric <span class="inline-formula">CH₄</span> from five arctic monitoring sites and presents estimates of the regional <span class="inline-formula">CH₄</span> fluxes for 2012–2015. The observational data reveal sizeable synoptic summertime enhancements in the atmospheric <span class="inline-formula">CH₄</span> that are distinguishable from background variations, which indicate strong regional fluxes (primarily wetland and biomass burning <span class="inline-formula">CH₄</span> emissions) around Behchoko and Inuvik in the western Canadian Arctic. Three regional Bayesian inversion modelling systems with two Lagrangian particle dispersion models and three meteorological datasets are applied to estimate fluxes for the Canadian Arctic and show relatively robust results in amplitude and temporal variations across different transport models, prior fluxes, and subregion masking. The estimated mean total <span class="inline-formula">CH₄</span> flux for the entire Canadian Arctic is <span class="inline-formula">1.8±0.6</span>&thinsp;Tg&thinsp;<span class="inline-formula">CH₄</span>&thinsp;yr<span class="inline-formula">⁻¹</span>. The flux estimate is partitioned into biomass burning of <span class="inline-formula">0.3±0.1</span>&thinsp;Tg&thinsp;<span class="inline-formula">CH₄</span>&thinsp;yr<span class="inline-formula">⁻¹</span> and the remaining natural (wetland) flux of <span class="inline-formula">1.5±0.5</span>&thinsp;Tg&thinsp;<span class="inline-formula">CH₄</span>&thinsp;yr<span class="inline-formula">⁻¹</span>. The summer natural <span class="inline-formula">CH₄</span> flux estimates clearly show inter-annual variability that is positively correlated with surface temperature anomalies. The results indicate that years with warmer summer conditions result in more wetland <span class="inline-formula">CH₄</span> emissions. More data and analysis are required to statistically characterize the dependence of regional <span class="inline-formula">CH₄</span> fluxes on the climate in the Arctic. These Arctic measurement sites will aid in quantifying the inter-annual variations and long-term trends in <span class="inline-formula">CH₄</span> emissions in the Canadian Arctic.</p>