Maximum Wave Height Retrieval for GPM Satellites Based on Dynamic Correction

Operational satellite retrieval of the maximum wave height (MWH) has long relied on linear wave theory, which estimates MWH as a fixed multiple of significant wave height (SWH). This static approach fails to capture the dynamic nonlinearity of real ocean waves, leading to systematic biases. In this study, we introduce a novel physics-based method that synergistically uses active and passive microwave observations from the Global Precipitation Measurement (GPM) mission to correct SWH dynamically and retrieve MWH directly. A dynamic correction factor is constructed from GMI brightness temperature—sensitive to wind induced energy input—and DPR radar backscatter—sensitive to wave steepness and nonlinear dissipation—thereby quantitatively diagnosing wave nonlinearity. Validated against 217 independent buoy observations, the proposed GPM MWH retrieval reduces the root mean square error (RMSE) and mean absolute error (MAE) by approximately 34% and 35%, respectively, compared to the ERA5 MWH product. This method demonstrates the feasibility of generating continuous, high resolution global MWH fields, offering a new pathway toward the operational monitoring of extreme ocean waves from space.