Climate-denying rumor propagation in a coupled socio-climate model: Impact on average global temperature

model parameters influences the model behavior at different time points. Time snapshots of parameter planes for emissions and temperature levels in 2021, 2070, and 2200 are considered. Emissions levels and temperature anomaly are more sensitive to changes in the emission- limiting value, C, than the changes in believing and rejecting probabilities (Figs 3 and 4). This means that the strength with which rejectors limit their emissions through various mitigation strategies can significantly reduce emission and temperature levels, which reestablishes the result from Fig 2. This also indicates that efforts to mitigate climate change are as important as the number of individuals who support mitigation. In other words, having individuals who adopt mitigative measures is as important as having individuals who acknowledge the climate crisis. Simultaneously increasing the probability of rejection and decreasing the probability of believing leads to lower levels of emissions and temperature (S2 Fig). This was done to under- stand how the combination of both these probabilities would aid in reducing emissions and it was observed that both believing and rejecting probabilities contribute to the temperature anomaly equally. The emission limit constant (C) has a greater influence on emission levels and temperature anomaly compared to the probabilities of believing (ω) and rejecting (z) (Figs 3 and 4) when the emission limiting strategies considered are lower. Decreasing the emission- limiting constant value after achieving the desired temperature goal can also cause an increase

in temperature, which implies that reducing the efficiency of mitigation strategies once the tar- get is achieved can take us to the initial scenario again. Hence it is important to maintain the efficiency in mitigating. The emission levels and temperature anomaly decrease as the forgetting probability in believers increases and the forgetting probability in rejectors decreases (S3 Fig). As more rejec- tors forget about the rumors, they become susceptible again, according to the rumor propaga- tion model, and hence the mitigation strategies decrease with a decrease in the rejector population. Whereas when more believers forget about the rumors, this leads to reduced Fig 3. Temperature sensitivity is more with variation in emission limiting constant than group believing probabilities. Parameter planes of CO2 emissions (GtCO2yr-1) at (a) 2021, (b) 2070, and (c) 2200 and temperature anomaly (˚C) at (d) 2021, (e) 2070 and (f) 2200 by varying group believing probability (ω) and emission limiting constant (C). https://doi.org/10.1371/journal.pone.0317338.g003 PLOS ONE Climate-denying rumor propagation in a coupled socio-climate model: Impact on average global temperature PLOS ONE | https://doi.org/10.1371/journal.pone.0317338 January 16, 2025 9 / 18