The Geostationary Operational Environmental Satellite (GOES)
Urgent Request Protocol System for Volcanic Observations
Monitoring of volcanic processes from orbit using thermal infrared (TIR) data has been ongoing from the earliest days of the satellite era. The Advanced Baseline Imager (ABI) instrument is one of six on the National Oceanic and Atmospheric Administration (NOAA) and National Aeronautics and Space Administration (NASA) GOES-R Series satellites launched in 2016 and 2017. ABI is the primary instrument on the GOES-R Series satellites used for primarily imaging Earth's weather, oceans, and environment. Here, ABI data is used for a volcanic hazard application. ABI acquires data in 16 different spectral bands (compared to five on the previous generation of GOES), including two visible channels, four near-infrared channels, and ten infrared channels. The instrument is a multi-channel passive imaging radiometer designed to observe the Western Hemisphere and provide variable area imagery and radiometric information of Earth�s surface, atmosphere and cloud cover. ABI full disk scan mode provides an image of the entire disk every 10 minutes.
The Geostationary Operational Environmental Satellite (GOES) Urgent Request Protocol (URP) System for Volcanic Observations was developed from the ASTER Urgent Request Protocol (URP) system. This original system was conceived in 2004 and implemented as a synergistic approach that would leverage ongoing operational volcanic monitoring programs that relied on high temporal/low spatial resolution satellites like AVHRR and MODIS to trigger (and eventually automate) the ASTER expedited data system (EDS), specifically for volcano monitoring and science. Over time, this protocol grew from a manual approach to an automated, successful global program since 2011.
Once a volcano is identified as having an increased thermal output (i.e., �thermal anomaly�), tools developed for the URP Program are integrated to automatically retrieve, process, and analyze GOES ABI data. For example, after the ASTER Emergency Scheduling Interface and Control System (AESICS) verifies the volcanic anomaly, the automated system downloads the corresponding full disk data from the AWS NOAA data server for the prior 6 months. The data is them spatial resampled and the radiance data is separated in temperature and emissivity data products using a modified TES algorithm originally developed for ASTER. The data are then processed to remove scenes obscured by meteoric clouds, remove sense with any non-volcanic anomalies, and calculate the above background temperatures. This is achieved through multiple temporal low pass filters similar to those used in MODIS temporal datasets. Finally, the above background temperatures are used to calculate the radiant heat flux (also known as radiant power). Timeseries analyses are then conducted to evaluate precursory and syn-eruption activity.
The entire process from the initial trigger to timeseries analysis takes less than 5 days. However, after a volcanic eruption has been initially integrated into the system it is updated daily until the activity has subsided. This enables near real-time monitoring, modeling, and forecasting of lava and ash/SO2 plumes at high temporal resolution.
The Geostationary Operational Environmental Satellite (GOES) Urgent Request Protocol (URP) System for Volcanic Observations is funded though the NASA grant 80NSSC20K1336.