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<p>GHGSat comprises a constellation of satellites with high spatial and spectral resolution that specialize in monitoring methane emissions at 1.65 <span class="inline-formula">µm</span>. This study investigates the ability to accurately retrieve both the methane mixing-ratio enhancement (<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M2" display="inline" overflow="scroll" dspmath="mathml"><mrow><mi mathvariant="normal">Δ</mi><msub><mi>X</mi><mrow class="chem"><msub><mi mathvariant="normal">CH</mi><mn mathvariant="normal">4</mn></msub></mrow></msub></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="32pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="fdde2d1935f5e081ead122dc5a8ad4f4"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-17-3347-2024-ie00001.svg" width="32pt" height="14pt" src="amt-17-3347-2024-ie00001.png"/></svg:svg></span></span>) and the aerosol optical depth (AOD) simultaneously from simulated GHGSat observations that incorporate angle-dependent scattering information. Results indicate that the sign of the <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M3" display="inline" overflow="scroll" dspmath="mathml"><mrow><mi mathvariant="normal">Δ</mi><msub><mi>X</mi><mrow class="chem"><msub><mi mathvariant="normal">CH</mi><mn mathvariant="normal">4</mn></msub></mrow></msub></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="32pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="78b133a460e3031930515b5f0223a900"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-17-3347-2024-ie00002.svg" width="32pt" height="14pt" src="amt-17-3347-2024-ie00002.png"/></svg:svg></span></span> bias when neglecting aerosols changes from negative to positive as surface albedo increases, which is consistent with previous studies. The bias in <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M4" display="inline" overflow="scroll" dspmath="mathml"><mrow><mi mathvariant="normal">Δ</mi><msub><mi>X</mi><mrow class="chem"><msub><mi mathvariant="normal">CH</mi><mn mathvariant="normal">4</mn></msub></mrow></msub></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="32pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="7b863537dfd204aa94e1fa1238951cbf"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-17-3347-2024-ie00003.svg" width="32pt" height="14pt" src="amt-17-3347-2024-ie00003.png"/></svg:svg></span></span> is most pronounced when AOD is not simultaneously retrieved, ranging from <span class="inline-formula">−</span>3.0 % to 6.3 % with an AOD of 0.1, a 60° solar zenith angle, and a surface albedo of 0.2 for the nadir-only retrieval. Using multiple satellite viewing angles during the GHGSat observation sequence with a scattering angle ranging from 100 to 140°, the study shows that the mean bias and standard deviation of <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M6" display="inline" overflow="scroll" dspmath="mathml"><mrow><mi mathvariant="normal">Δ</mi><msub><mi>X</mi><mrow class="chem"><msub><mi mathvariant="normal">CH</mi><mn mathvariant="normal">4</mn></msub></mrow></msub></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="32pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="c3dee0a0780a8e08802a32c80b0acfcf"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-17-3347-2024-ie00004.svg" width="32pt" height="14pt" src="amt-17-3347-2024-ie00004.png"/></svg:svg></span></span> are within 0.3 % and 2.8 % relative to the background. The correlation between simultaneously retrieved <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M7" display="inline" overflow="scroll" dspmath="mathml"><mrow><mi mathvariant="normal">Δ</mi><msub><mi>X</mi><mrow class="chem"><msub><mi mathvariant="normal">CH</mi><mn mathvariant="normal">4</mn></msub></mrow></msub></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="32pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="a28008053761495a4462ba5db4d64c4b"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-17-3347-2024-ie00005.svg" width="32pt" height="14pt" src="amt-17-3347-2024-ie00005.png"/></svg:svg></span></span> and AOD shifts from being positive to negative as surface albedo increases and the aerosol asymmetry factor decreases, signifying a transition of the dominant aerosol effect from aerosol-only scattering to aerosol–surface multiple scattering. The variety of scattering angle ranges has little impact on the performance of the multi-angle viewing method. This study improves the understanding of the impact of aerosols on the GHGSat <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M8" display="inline" overflow="scroll" dspmath="mathml"><mrow><mi mathvariant="normal">Δ</mi><msub><mi>X</mi><mrow class="chem"><msub><mi mathvariant="normal">CH</mi><mn mathvariant="normal">4</mn></msub></mrow></msub></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="32pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="0b1cee303d255d47f7ff6679e01de468"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-17-3347-2024-ie00006.svg" width="32pt" height="14pt" src="amt-17-3347-2024-ie00006.png"/></svg:svg></span></span> retrieval and provides guidance for improving future GHGSat-like point-source imagers.</p>