Eigen Microstates and Their Evolution of Global Ozone at Different Geopotential Heights

TL;DR

This paper introduces the eigen microstate method to analyze global ozone variations across different geopotential heights, revealing climate phenomena and modes without prior deseasonalization, and offers a new theoretical framework for complex Earth systems.

Contribution

The paper presents a novel eigen microstate approach to analyze ozone variability, capturing climate modes and phenomena at different heights, and provides a generalizable theoretical framework.

Findings

Eigen microstates capture seasonal effects and phase shifts at different heights.

Deseasonalized analysis reveals ENSO, QBO, and tropopause pressure patterns.

Method applicable to other complex Earth system analyses.

Abstract

Studies on stratospheric ozone have attracted much attention due to its serious impacts on climate changes and its important role as a tracer of Earth's global circulation. Tropospheric ozone as a main atmospheric pollutant damages human health as well as the growth of vegetation. Yet there is still a lack of a theoretical framework to fully describe the variation of ozone. To understand ozone's spatiotemporal variance, we introduce the eigen microstate method to analyze the global ozone mass mixing ratio (OMMR) between 1979-01-01 and 2020-06-30 at 37 pressure layers. We find that eigen microstates at different geopotential heights can capture different climate phenomena and modes. Without deseasonalization, the first eigen microstates capture the seasonal effect and reveal that the phase of the intra-annual cycle moves with the geopotential heights. After deseasonalization, by contrast, the collective patterns from the overall trend, ENSO, QBO, and tropopause pressure are identified by the first few significant eigen microstates. The theoretical framework proposed here can also be applied to other complex Earth systems.