Carbon Dioxide Emissions During the 2018 Kilauea Volcano Eruption Estimated Using OCO‐2 Satellite Retrievals

Abstract

This study applies Orbiting Carbon Observatory-2 (OCO-2) column-averaged dry-air mole fractions of CO 2 (XCO 2) to constrain CO 2 fluxes during the 2018 Kilauea volcano eruption. CO 2 enhancements (ΔXCO 2) of 1-2 parts per million were observed far downwind of the eruption coincident with elevated sulfur dioxide (SO 2) concentrations. The estimated CO 2 emission rate was 77.1 ± 49.6 kilotons per day (kt day −1) on 11 July 2018 with most of the uncertainty from modeled winds and XCO 2 retrievals. This emission rate is higher compared to flux estimates made with ground-based measurements (30-40 kt day −1). However, cross-sectional flux estimates made using OCO-2 XCO 2 observations will inherently be larger than ground-based measurements near the source as these estimates comprise all sources of CO 2 in the vicinity of the eruption (e.g., vegetation and soil burning). This study for the first time uses satellite XCO 2 data~200 km downwind to estimate CO 2 emissions from a major volcanic eruption. Plain Language Summary Carbon dioxide (CO 2) is a greenhouse gas that plays a predominant role in climate change. Volcanoes emit CO 2 and play a role in the global carbon cycle; however, the amount of CO 2 they emit is highly uncertain. One of the main reasons for this uncertainty is the limited amount of volcanic emission measurements available to estimate these CO 2 emissions. Satellites retrieving CO 2 have an advantage over ground-based measurements as they have the potential to obtain data over the entire globe. After the launch of National Aeronautics and Space Administration (NASA)'s Orbiting Carbon Observatory-2 (OCO-2) satellite in 2014, spaceborne observations of volcanic CO 2 were possible. This study uses OCO-2 measurements of CO 2 to estimate emissions during the 2018 Kilauea volcano eruption and is the first to trace satellite CO 2 data downwind from the source of a major volcanic eruption. Here we show that the Kilauea volcano eruption emitted large amounts of CO 2 and OCO-2 proved capable to observe the large atmospheric concentrations associated with these emissions.

Assessing the Ecological Implications of Ocean Iron Fertilization: Insights from Post-Eruption Volcanic Processes

“…However, despite its contribution to global warming, Kilauea also has the ability to offset gas emissions through organic processes. Approximately 10 million kilograms of CO2 are consumed by phytoplankton in the sea, which accounts for nearly 12 percent of Kilauea's net carbon emissions on an active eruptive day [17]. NASA's satellite identified a visible cluster of green biomass surrounding Kilauea within six months of its most recent eruption in December 2021.…”

A golden era for volcanic gas geochemistry?

“…To date, satellite measurements mainly target SO2 in the UV spectral region, with the Tropospheric Monitoring Instrument (TROPOMI) currently providing daily global coverage at unprecedented 3.5 x 7 km resolution (Theys et al 2019). In certain conditions, satellite-borne IR spectroscopy can also provide information on SO2, H2S, HCl, sulfate aerosol, ash, and possibly even CO2, though the latter is extremely challenging due to the high atmospheric background CO2 concentration and current technology will only allow quantitative CO2 detection on rare occasions (Carn et al 2016;Clarisse et al 2010Clarisse et al , 2011Clarisse et al , 2012Johnson et al 2020;Schwandner et al 2017). We expect that continuous geochemical monitoring will expand greatly in the next 10 years, motivated by the extremely promising results from volcanoes that have been instrumented or where campaign measurements were fortuitously performed at key moments.…”

Development of Secondary Forest Succession Based on Estimation of Forest Carbon Stocks Ten Years Post-Merapi Volcano Eruption

“…A volcanic eruption is a non-anthropogenic event that is the source of stored carbon released from the Earth to the atmosphere (Brune et al 2017;Fischer et al 2019). The ring of fire in the tropical rain forest is the most vulnerable area to release carbon up to 31±22 × 1012 g CO 2 year -1 through materials exposure and forest fires that occur afterward (Johnson et al 2020;Williamns et al 1992;Zhang et al 2019). Mount Merapi is the most active volcano in the tropical area of Indonesia (Gunawan et al 2013), even one of the most active in the world (Voight et al 2000).…”