[P-EM09] Space Weather and Space Climate

[PEM09-P14] Annual total ionizing dose on the geostationary meteorological satellite Himawari8 estimated from the SEDA observation

*Kaori Sakaguchi¹, Shinji Saito¹, Tsutomu Nagatsuma¹ (1.National Institute of Information and Communications Technology)

Keywords:Total ionizing dose, energetic particles observation, geostationary orbit

Total ionizing dose (TID) effects are common problem in space. Major sources of TID at geostationary orbit are energetic electrons in the outer Van Allen radiation belt and solar energetic particles (SEPs) accompanied by solar flares. Space environment data acquisition monitor (SEDA) onboard Japanese geostationary meteorological satellite Himawari8 have been observing energetic electrons and protons since November 2014. Yearly changes in TID are estimated from the SEDA observation in 2015–2022 by inputting data to SHIELDOSE-2 model assuming 1-mm Aluminum sphere shield. It is found that annual electron dose is highest in 2017 and lowest in 2020, it is less than half of 2017. Also, annual proton dose is found highest in 2017, followed by 2015, 2021, and 2022, but in any year other than these no major SEPs have occurred. TID is commonly estimated from the AE8 trapped electron model and JPL-1991 SEPs models. By comparison, the estimated TID from SEDA is several times lower than the TID estimated based on the AE8 and JPL1991 models.