Mounting countries worldwide are implementing net-zero emission projects to mitigate the adverse impacts of anthropogenic CO 2 emissions and the associated global warming. However, due to the inherent inertia of the climate system and the influence of non-CO 2 greenhouse gases, temperatures may continue to rise even after the global atmospheric CO 2 concentration peaks. Using the latest climate models, we investigate regional temperature changes under net-zero emission scenarios, taking the Tibetan Plateau (TP) as an example, focusing on the time lag between the peaks of temperature and CO 2 concentrations, as well as the additional risks associated with delayed net-zero emission. Our results indicate an overall warming of 1.4 and 2.1 °C in SSP1-1.9 and SSP1-2.6 scenarios by the end of the 21st century relative to the 1985–2014 baseline, with a larger warming magnitude in the eastern TP and more uniform warming in the early and late net-zero emission scenarios, respectively. Most climate models reveal a time lag between the CO 2 concentration peak and the surface air temperature peak ranging from years to decades. The northern and eastern TP experience the longest time lag under the early net-zero emission scenario, while the western TP shows the largest time lag for delayed net-zero emission. Postponing net-zero emission by 20 years adds at least an additional 0.8 °C warming to the mean temperature, with even larger increases of 1.0 °C in extreme temperatures.
Wang et al. (Thu,) studied this question.