From the paper: In conclusion, the temporary ‘slowdown’ in warming in the early twenty-first century has provided the scientific community with a valuable oppor

From the paper: In conclusion, the temporary ‘slowdown’ in warming in the early twenty-first century has provided the scientific community with a valuable opportunity to advance understanding of internal variability and external forcing, and to develop improved climate observations, forcing estimates, and model simulations. Further work is necessary to reliably quantify the relative magnitudes of the internally generated and externally forced components of temperature change. It is also of interest to explore whether surface temperature yields results consistent with those obtained here for tropospheric temperature. Our analysis is unlikely to reconcile divergent schools of thought regarding the causes of differences between modelled and observed warming rates in the early twenty-first century. However, we have shown that each hypothesized cause may have a unique statistical signature. These signatures should be exploited in improving understanding. Although scientific discussion about the causes of short-term differences between modelled and observed warming rates is likely to continue19, this discussion does not cast doubt on the reality of long-term anthropogenic warming.