Four, Three, Two, One... Whats Up (or Down) with the TSI Instruments?
Abstract
Over the last three years, the number of spaceborne instruments producing measurements of the total solar irradiance (TSI), the TOA net incoming energy powering the Earths climate system, has decreased from four to one. This 43-year-long record of solar variability has depended on continuity and overlap of successive instruments but is now completely reliant on the Total Irradiance Monitor flying on the International Space Station. Fortunately, this is a short-term trend in this climate data record and not an intended long-term trend. We summarize the recent turnover (or, more correctly, turn-off) causing the declining number in the instrument suite contributing to the TSI record. Then, before extrapolating-based panic might set in, we provide a more optimistic look at the future of these measurements and the several instruments currently being readied for launch, some of which include fresh designs enabled by new materials and calibration approaches. We will also discuss updates to a composite TSI record using the entire collection of instruments from the spacecraft era as well as mentioning the accuracies and stabilities of the recent measurements. Finally, we mention an effort underway to extend the TSI record to historical times via updates to sunspot-number records, modern flux-transport models, and proxy-based TSI-reconstruction models.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFMGC24E..04K