Driven by advances in supercomputing, the scale of scientific simulation data has grown dramatically. In fields such as cosmology, particle data have become a common representation, with state-of-the-art simulations now exceeding the trillion-particle mark. Consequently, the challenge of visually analyzing such massive datasets has become increasingly urgent. The traditional visual analysis workflow typically follows a "compression $\rightarrow$→ storage $\rightarrow$→ reconstruction $\rightarrow$→ visualization" pipeline. However, this process is hampered by an extremely time-consuming reconstruction stage, which severely impedes real-time interactive visualization. Moreover, in multi-time-step analyses, the enormous volume of reconstructed data creates significant I/O bottlenecks. In this work, we draw inspiration from 3D Gaussian splatting and compress the simulation data using Gaussian Mixture Models (GMMs), treating the resulting Gaussian kernels as fundamental rendering primitives. Our method renders billion-scale particles for each timestep in approximately 32 ms, requiring only 645 MB of GPU memory per timestep - nearly 20× smaller than the original 12 GB raw data. This eliminates costly reconstruction, accelerates the visual analysis pipeline, and overcomes I/O bottlenecks in multi-time-step analysis. Extensive experiments and comparisons across multiple datasets validate the effectiveness of our method.

Meteorological experts achieved promising results in improving the effectiveness of neural weather networks in precipitation forecasting by incorporating precipitation-optimized objectives into the loss function. However, since neural networks are not based on explicit physical processes, meteorological experts may lack understanding and trust in the model’s predictions, and they cannot perform bias correction by adjusting physical parameters. Additionally, precipitation events are highly imbalanced, with heavy rainfall events being relatively rare but of greater importance. Therefore, traditional metrics for evaluating deep models are insufficient to fully assess precipitation forecasting performance. In this paper, we present a neural weather network visual analysis system designed to help domain experts understand and comprehensively compare the impact of different loss functions on neural networks. We customize the model evaluation process based on the characteristics of precipitation forecasting tasks and provide a reference for bias correction using historically similar data. To validate our approach, we perform two case studies using real-world reanalysis datasets, with feedback from domain experts further confirming its effectiveness.