... that climate science is settled and everything is your fault. Well that’s what some of them say. Others keep finding that the picture is more complicated and there are big processes driving climate change that aren’t included in climate models because no one is quite sure how they work. As in: decadal mismatches between model-simulated and observed climate trends are common throughout the twentieth century, and their causes are still poorly understood.... While climate models exhibit various levels of decadal climate variability and some regional similarities to observations, none of the model simulations considered match the observed signal in terms of its magnitude, spatial patterns and their sequential time development. These results highlight a substantial degree of uncertainty in our interpretation of the observed climate change using current generation of climate models. Scientists say.
The linked article discusses decadal climate variability or DCV as they call it. Lots of research over the years has identified regional cycles that affect weather patterns over parts of the globe, such as the North Atlantic Oscillation, the Pacific Decadal Oscillation, the Arctic Oscillation and the Ranfurly Oscillation (we made that last one up because we like the name). The article points out that there’s an even bigger pattern at work whereby large, slow changes in the climate system emerge spontaneously in the North Atlantic, whose oscillation sends the temperature cycle outward to the Pacific, whose oscillation then transmits it to the Southern Oceans and from there it gets transmitted to the Antarctic. The whole process, which they dub a “stadium wave” for the global climate, takes 25-35 years to complete. And while it shows up in the data and drives observed trends and changes, climate models can’t reproduce it.
Although some of the climate models are able to simulate certain qualitative features of the observed DCV, our results summarise and rigorously document pronounced quantitative discrepancies between models and observations, which should help guide further DCV research.
So the climate is complicated, models miss a lot of important details and more research is needed. Scientists say.