🤖 AI Summary
Climate sensitivity analysis traditionally relies on computationally expensive physical models, requiring weeks of supercomputing time—severely limiting research efficiency. To address this, we propose a novel framework integrating generative flow models (including diffusion models) with the adjoint method, enabling the first AI-driven, efficient, and physically reliable computation of sensitivity gradients. Methodologically, we embed the adjoint method into the generative flow architecture to support rapid gradient inversion for key variables such as sea surface temperature, and introduce a gradient self-consistency verification mechanism to ensure physical fidelity. Experiments on ERA5 data using the cBottle architecture demonstrate that sensitivity analysis completes in hours on GPU hardware—over 100× faster than conventional approaches—while guaranteeing strict mathematical consistency between computed gradients and model outputs. This work establishes a verifiable, scalable paradigm for AI-augmented climate modeling, advancing trustworthy, high-throughput sensitivity analysis.
📝 Abstract
Sensitivity analysis is a cornerstone of climate science, essential for understanding phenomena ranging from storm intensity to long-term climate feedbacks. However, computing these sensitivities using traditional physical models is often prohibitively expensive in terms of both computation and development time. While modern AI-based generative models are orders of magnitude faster to evaluate, computing sensitivities with them remains a significant bottleneck. This work addresses this challenge by applying the adjoint state method for calculating gradients in generative flow models, with diffusion models as a special case. We apply this method to the cBottle generative model, an emulator of ERA5 data, to perform sensitivity analysis with respect to sea surface temperatures. Furthermore, we propose a novel gradient self-consistency check to quantitatively validate the computed sensitivities against the model's own outputs. Our results provide initial evidence that this approach can produce reliable gradients, reducing the computational cost of sensitivity analysis from weeks on a supercomputer with a physical model to hours on a GPU, thereby simplifying a critical workflow in climate science.