World’s fastest supercomputer boosts US tsunami warning systems

US scientists at Lawrence Livermore National Laboratory (LLNL) have developed a real-time tsunami forecasting system powered by El Capitan, the world’s fastest supercomputer with a peak performance of 2.79 quintillion calculations per second. Utilizing over 43,500 AMD Instinct MI300A Accelerated Processing Units, the system solves complex acoustic-gravity wave propagation problems to create a detailed "digital twin" model of tsunami behavior. This model integrates real-time seafloor pressure sensor data with advanced physics-based simulations to infer earthquake-induced seafloor motion and predict tsunami wave propagation with quantified uncertainties, enabling rapid forecasts during actual events. The breakthrough hinges on solving a billion-parameter Bayesian inverse problem with unprecedented speed—less than 0.2 seconds—achieving a 10-billion-fold speedup compared to previous methods. This was made possible by leveraging El Capitan’s exascale computing power in an offline precomputation step, allowing subsequent rapid predictions on smaller GPU clusters. The system