Monthly TSI for "Prospects for Detecting Accelerated Global Warming"

Stitched monthly TSI reconstruction as used in:
Richardson M "Prospects for Detecting Accelerated Global Warming"
Submitted to: Geophys. Res. Lett. 2021

This is constructed from daily PMOD, SORCE and TSIS data, with linear interpolation between missing values before taking the monthly average.

Please cite the original data sources:
PMOD: ftp://ftp.pmodwrc.ch/pub/data/irradiance/composite/composite_42_65_1709.dat  and: https://doi.org/10.1007/s11214-006-9046-5
SORCE-TIM: http://lasp.colorado.edu/data/sorce/tsi_data/daily/sorce_tsi_L3_c24h_latest.txt and: https://doi.org/10.1007/s11207-005-7446-4
TSIS: http://lasp.colorado.edu/data/tsis/tsi_data/tsis_tsi_L3_c24h_latest.txt and: https://doi.org/10.5067/TSIS/TIM/DATA306