Performance of the LFSO2 algorithm at NOAA for near real time monitoring volcanic SO2 cloud

The Linear Fit SO2 (LFSO2) algorithm has been adapted by NOAA to create total column SO2 products from OMPS Nadir Mapper (NM) measurements in an operational system. This algorithm uses measurement residuals from the version 8 ozone retrieval algorithm to estimate the total column amount of SO2 in the atmosphere. In order to provide a faster response time for natural disaster prediction, a 15-granule overlapping processing scheme has been designed. In this scheme, the LFSO2 has been implemented as an independent program combined with Version-8 total ozone retrieval algorithm (V8TOZ). The V8TOZ will process OMPS/NM Sensor Data Records (SDR) on a granule-by-granule basis. Whenever a consecutive 15 granules of ozone Environment Data Record (EDR) are available, the LFSO2 will be triggered to start its processing. The average residuals for the 15 granules are used to provide background values for the SO2 for the middle five granules. The SO2 estimates and adjusted ozone retrievals are saved for these five granules. Processing then steps forward five granules at a time along the full orbit. This processing scheme provide an every 175 second disaster monitoring. In this presentation, we will briefly introduce the algorithm, demonstrate how 15-granule scheme works, and show some examples of how LFSO2 can provide monitoring volcano eruptions. We include comparisons of NOAA OMPS LFSO2 product with NASA retrievals from OMI and OMPS. We also present results of the total column ozone retrieval corrected for the presences of SO2.