## 3 Results
### Energy Balance  
Net radiation is affected by all forcings, although there is a regional difference. The net radiation under historical forcing showed that the energy absorbed on the ground decreased globally over a long-term trend (Figure 4a,b) before rebounding in the near past (1970-2010). By comparing the results of the pre-1970s and post-1970s (Figure 4a,c), such bouncing appears to be contributed by advanced countries on the continents of North America and Europe. In contrast, the net radiation in Asian regions decreased even more dramatically after 1970s (Figure 4c,d) mainly because aerosol emissions have increased in Asia. Asian regions have seen a significant increase in aerosol after industrialization, which can be the main reason for a consistent decrease in short wave radiation as reported in a previous study [51]. Furthermore, the MLRM analysis indicated that the total absorbed energy  
Figure 3: Results of precipitation (PR) and temperature (TAS) analyses: (**a**) 50-year mean start-to-end difference of precipitation; (**b**) time series plot of global precipitation; (**c**) 50-year mean start-to-end difference of temperature; (**d**) time series plot of global temperature. The titles above the plots and the legends within the plots are followed by the number of ensemble models in parentheses, and the estimated parameters with hats provide the statistical significance. On the maps, the dots indicate where the differences are significant (\(p\)-value \(\leq\) 0.05).  
(net radiation) is affected not only by AER but also by GHG and NAT to a remarkable extent (Figure 4b). The effects of the estimated MLRM parameters are visually recognizable in the figure; for instance, AER and GHG forcing increased and decreased net radiation, respectively, as evidenced in the temperature and PR trends. The decreasing trend in the historical simulation (global deeming) followed the AER simulation, and the rebounding trend since 1970 (global brightening in Eastern USA and Europe) followed GHG results [52]. By utilizing net radiation, we can clearly identify the role of NAT in short historical frequency; specifically, the major variations in the short frequency coincide with major volcanic activities [53].  
The long-term variations in both latent heat (\(\sim\)Evapotranspiration, ET) and sensible heat (SH) fluxes tended to follow net radiation. However, the forcings of ET and SH have different weights although the two variables are bound in net radiation: AER dominantly affects SH, and both AER and GHG dominantly influence ET on a global scale (Figure 5). Given the strong effect of AER on SH and the summation relationship, we can expect that GHG can dominantly affect ET. As observed for the other variables, the contribution of ET was regionally variable. In East Asia, ET is mainly controlled by AER and NAT, but in South Asia, ET was not significantly affected by any forcing (no figures provided). We additionally estimated the ET (\(\sim\)\(\lambda\)E) portion ET/(ET + SH), which is similar to the Bowen Ratio ET/SH (Figure 5e,f). The ET ratio has been steadily increasing globally and in East Asia, although PR and net radiation have fluctuated throughout historical records. Interestingly, the ratio followed the GHG-only simulation, which also predicted an increasing trend, indicating that GHG might strongly contribute to ET variation. An elevated ET ratio implies a wet surface climate of land [54].  
Figure 4: Result of the Net Radiation (ETHSUM) analysis: (**a**) 50-year mean start-to-end differences in net radiation (1850–2010); (**b**) time series plot of global net radiation; (**c**) 10-year mean start-to-end differences in net radiation (1970–2010); (**d**) time series plot of global net radiation. The titles above the plots and the legends within the plots are followed by the number of ensemble models in parentheses, and the estimated parameters with hats indicate statistical significance. On the maps, dots indicate where the differences are significant (\(p\)-value \(\leq\) 0.05).