Volcanic fissure eruptions can produce voluminous gas emissions, posing a risk to local and distal populations and potentially impacting global climate. Quantifying the emission rate and altitude of injection of these emissions allows forecasting of impacts and provides key insights into the magma dynamics driving eruptions. Daily global observations from satellite instruments such as TROPOMI combined with trajectory modelling with PlumeTraj deliver these emission rate and altitude data. Here, we report satellite-derived SO2 emissions from the 2022 eruption of Mauna Loa, which lasted only 13 days but produced an SO2 plume that circled the globe, displaying a highly variable emission rate and injection altitude. Three key discoveries were made: we detect precursory SO2 emissions up to 3 h before the eruption start; peaks in emission rate are correlated with onset and cessation of activity at different fissures; the SO2 injection altitude was modulated by the available moisture content of the ambient air. We suggest that alignment of the fissure geometry with the wind direction could potentially explain how the initial emissions reached 14 km asl, approaching the tropopause. The total SO2 measured from this eruption is 600 (± 300) kt. These results demonstrate how satellite measurements can provide new insights into eruptive and degassing mechanisms and highlight that better constraints on the SO2 emissions from fissure eruptions globally are needed to understand their impact on climate.