GHOTI: Using the GOES-R EXIS/SPS detectors to create a low-latency, high-cadence, TSI proxy and spectral models
- 1University of Colorado - Boulder, LASP, CO, United States of America (steven.penton@lasp.colorado.edu)
- 2South African National Space Agency (SANSA), Hermanus, South Africa (msnow@sansa.org.za)
- 3University of Colorado - Boulder, LASP, CO, United States of America
The GOES-R series of geostationary satellites include a redesigned instrument for solar spectral irradiance:
the Extreme ultra-violet and X-ray Irradiance Sensor (EXIS). Our team will be using the Sun Position Sensor (a set of high-cadence broadband visible light diodes) on GOES-16 and GOES-18 EXIS instruments to construct a high-cadence proxy for Total Solar Irradiance (TSI). This has two advantages over the existing TSI measurements:
1) the measurements are taken at 4 Hz, so the cadence of our TSI proxy is much faster than existing measurements, such as the 6 to 24-hour measurements produced by SORCE or TSIS-1, and
2) from a geostationary position, the time series of measurements is virtually uninterrupted.
Our calibration of the GOES-R EXIS diode measurements includes thermal and sun-satellite distance corrections,
while the irradiance calibration relies on TSIS-1 TIM TSI composites. Another measurement from GOES-EXIS that will be used is the Magnesium II core-to-wing ratio. The MgII index is a proxy for chromospheric activity and is measured by EXIS every 3 seconds. The combination of the two proxies is used to generate a model of the full solar spectrum similar to the NRLSSI2 empirical model.
We are in the final year of a four-year grant to develop the TSI proxy and the SSI model.
How to cite: Penton, S., Snow, M., Béland, S., Woodraska, D., and Coddington, O.: GHOTI: Using the GOES-R EXIS/SPS detectors to create a low-latency, high-cadence, TSI proxy and spectral models, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20938, https://doi.org/10.5194/egusphere-egu24-20938, 2024.
