Calibrated and Enhanced NRLMSIS 2.0 Model with Uncertainty Quantification

TL;DR

This paper introduces MSIS-UQ, a machine learning-based uncertainty quantification model that calibrates NRLMSIS 2.0, improving its accuracy and providing probabilistic estimates for atmospheric density and temperature profiles.

Contribution

The work develops a novel ML-based uncertainty quantification method for NRLMSIS 2.0, enabling calibration and probabilistic predictions of atmospheric parameters.

Findings

MSIS-UQ reduces model-satellite density differences by 25%.

MSIS-UQ is 11% closer to satellite data than the High Accuracy Satellite Drag Model.

The model effectively captures uncertainty in density and temperature profiles.

Abstract

The Mass Spectrometer and Incoherent Scatter radar (MSIS) model family has been developed and improved since the early 1970's. The most recent version of MSIS is the Naval Research Laboratory (NRL) MSIS 2.0 empirical atmospheric model. NRLMSIS 2.0 provides species density, mass density, and temperature estimates as function of location and space weather conditions. MSIS models have long been a popular choice of atmosphere model in the research and operations community alike, but - like many models - does not provide uncertainty estimates. In this work, we develop an exospheric temperature model based in machine learning (ML) that can be used with NRLMSIS 2.0 to calibrate it relative to high-fidelity satellite density estimates. Instead of providing point estimates, our model (called MSIS-UQ) outputs a distribution which is assessed using a metric called the calibration error score. We show that MSIS-UQ debiases NRLMSIS 2.0 resulting in reduced differences between model and satellite density of 25% and is 11% closer to satellite density than the Space Force's High Accuracy Satellite Drag Model. We also show the model's uncertainty estimation capabilities by generating altitude profiles for species density, mass density, and temperature. This explicitly demonstrates how exospheric temperature probabilities affect density and temperature profiles within NRLMSIS 2.0. Another study displays improved post-storm overcooling capabilities relative to NRLMSIS 2.0 alone, enhancing the phenomena that it can capture.