KORUS-AQ (Korea-U.S. Air Quality Study) is a NASA-led aircraft mission that took place in spring 2015 across the South Korean Peninsula.
Our group has focused on quantifying emissions due to rice cultivation and air pollution feedbacks on these emissions. KORUS-AQ science flights occurred during regional rice transplantation and paddy flooding, a period of rapid biogeochemical transition (aerobic to anaerobic conditions) in rice fields. With almost 106 hectares of rice grown in South Korea (10% of national landcover), rice paddy biogeochemistry has the potential to influence the atmospheric concentrations of methane and nitrous oxide, as well as small reactive organic acids and alcohols. While paddy biogeochemistry is well described at the organismal scale, KORUS-AQ produced the first suite of measurements with which to test biogeochemical controls at regional spatial scales. Additionally, South Korea experiences severe air pollution, including high concentrations of secondary aerosol. Our work quantifies the extent to which sulfate and nitrate aerosol deposition alters rice soil biogeochemistry and affects paddy emissions. This work is funded by NASA.