Patch-Based Deep Kernel Learning for Data Assimilation and Bias Correction with Extremely Sparse Observations
The paper proposes a hybrid framework that couples a CNN with a learnable-kernel Gaussian process to jointly perform data assimilation and bias correction from extremely sparse observations. A patch-based strategy reduces exact-GP training cost from O(N^3) to O(N) for a fixed patch size, while inference cost depends on the number of observations rather than the full grid. Experiments on sea surface temperature and salinity with synthetic and real sparse in-situ observations show improvements over 3D-Var, a classical GP, and a competing deep-learning model, with inference time reduced by more than 98% relative to 3D-Var.
Why it matters: It offers a concrete AI method for uncertainty-aware data assimilation and bias correction, with efficiency and accuracy claims relevant to weather and ocean modeling.