Reliance on Models and Reanalysis Data with Limitations
The study relies on climate models and reanalysis data, which have known limitations and biases. For example, the forecast model does not include factors like solar cycle variability or shipping emissions, which could have influenced the observed warming. Additionally, the model did not account for aerosols from the Hunga Tonga eruption, which might have had a cooling effect.
Need for Further Investigation into Complex Interactions
While the study identifies El Niño and net absorbed TOA SW radiation as key drivers of the 2023 warming, the complex interplay of these and other factors needs further investigation. It's crucial to disentangle the relative contributions of each driver to fully understand the observed temperature surge.
Model Underestimation of Anomalies over Land
The study acknowledges that the forecast model underestimates the magnitude of observed anomalies, particularly over land. This highlights a potential limitation in the model's ability to accurately represent land-atmosphere interactions and their influence on temperature changes.