Audette et al. (2026) Numerical Water Tracers in the Atmospheric Component of the Energy Exascale Earth System Model: Implementation and Changes in Moisture Origin

⚠️ Warning: This summary was generated from the abstract only, as the full text was not available.

Identification

• Journal: Journal of Advances in Modeling Earth Systems
• Year: 2026
• Date: 2026-04-01
• Authors: Alexandre Audette, Nicole Feldl, Hansi Singh, Kyle Heyblom, Hailong Wang, Jesse Nusbaumer, Hui Wan, Kai Zhang
• DOI: 10.1029/2025ms005287

Research Groups

Not explicitly mentioned in the abstract.

Short Summary

This study implements numerical water tracers in the E3SMv2 model to investigate changes in the global hydrologic cycle under future climate scenarios, revealing increased moisture export from mid-latitude and southern subtropical regions and enhanced local evaporation in polar areas. A novel statistical reconstruction method for water vapor origin is also proposed to reduce computational cost.

Objective

• To understand the changes in the global hydrologic cycle, particularly atmospheric moisture sources and transport pathways, under future greenhouse gas concentrations using numerical water tracers in the Energy Exascale Earth System Model version 2 (E3SMv2).

Study Configuration

• Spatial Scale: Global, covering mid-latitudes, subtropical regions, extratropics, tropics, and polar regions.
• Temporal Scale: Long-term climate simulations comparing pre-industrial and future greenhouse gas concentration scenarios.

Methodology and Data

• Models used: Energy Exascale Earth System Model version 2 (E3SMv2) with numerical water tracers (water tags); Copula modeling for statistical reconstruction of water vapor origin.
• Data sources: Model simulations performed with E3SMv2.

Main Results

• Mid-latitude and southern subtropical regions show a marked increase in their role as exporters of atmospheric moisture to the extratropical upper troposphere and tropical free troposphere.
• The northward shift of the Intertropical Convergence Zone (ITCZ) enhances cross-hemispheric transport of subtropical water vapor to the Northern Hemisphere.
• In polar regions, the majority of lower tropospheric moistening is attributed to increases in local evaporation.
• A novel statistical reconstruction method, utilizing copula modeling, was developed to reduce the computational cost of water tracers by decreasing the number of tracers from order $N^2$ to order $N$.
• This statistical reconstruction improves the interpretation of the relationship between latitude and longitude of moisture origin, especially over tropical oceans and in the lower troposphere over land.

Contributions

• First implementation and application of numerical water tracers within the Energy Exascale Earth System Model version 2 (E3SMv2) to study global hydrologic cycle changes.
• Provides novel insights into the evolving roles of different regions as moisture sources and the dynamics of atmospheric moisture transport under future climate conditions.
• Introduces a significant methodological advancement with a novel statistical reconstruction technique (copula modeling) that drastically reduces the computational burden of water tracer simulations, making global grid applications more feasible.

Funding

Not explicitly mentioned in the abstract.

Citation

@article{Audette2026Numerical,
  author = {Audette, Alexandre and Feldl, Nicole and Singh, Hansi and Heyblom, Kyle and Wang, Hailong and Nusbaumer, Jesse and Wan, Hui and Zhang, Kai},
  title = {Numerical Water Tracers in the Atmospheric Component of the Energy Exascale Earth System Model: Implementation and Changes in Moisture Origin},
  journal = {Journal of Advances in Modeling Earth Systems},
  year = {2026},
  doi = {10.1029/2025ms005287},
  url = {https://doi.org/10.1029/2025ms005287}
}