Comparing satellite and ground-based measurements of low-lying SO2 plumes during the Kilauea 2018 and 2020 eruptions

Ground and satellite SO₂ measurements have been extensively compared for high altitude volcanic emissions but far less for grounded plumes. The 2018 and 2020 Kilauea eruptions offered perfect opportunities to compare our TROPOMI results with ground measurements. Not only is Kilauea a very well monitored volcano, so the ground measurements are abundant and reliable, the SO₂ plumes were big enough to be picked up by satellite. We compared the results to assess the efficacy of TROPOMI as a remote sensing tool applied at low-lying SO₂ plumes. We concluded that the fluxes for both agreed provided the wind speed is the same for both. Remote sensing is therefore an important tool for effusive eruption monitoring and could be used on its own at remote volcanoes where ground instruments are sparse or lacking.