EGUsphere

Copernicus Publications

Göttingen, Germany

10.5194/egusphere-2026-3062

GC Insights: On The Definition of Aridity in Geoscience Research

Good

Stephen

https://orcid.org/0000-0003-4363-1577

¹ ² Haagsma

Marja

https://orcid.org/0000-0002-1777-7284

¹ Avila

Colton

¹ Bulter

Zachariah

https://orcid.org/0009-0007-0883-7103

¹ ² ³ Barinas

Garbriel

https://orcid.org/0000-0002-2054-6698

¹ ² Chen

Han

¹ Huang

Tingting

¹ ²

Department of Biological and Ecological Engineering, Oregon State University, Corvallis OR, USA

Water Resources Graduate Program, Oregon State University, Corvallis OR, USA

Civil and Construction Engineering, Oregon State University, Corvallis OR, USA

02 09 2026

2026 1 10

2026

This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/

This article is available from https://egusphere.copernicus.org/preprints/2026/egusphere-2026-3062/

The full text article is available as a PDF file from https://egusphere.copernicus.org/preprints/2026/egusphere-2026-3062/egusphere-2026-3062.pdf

Aridity is a fundamental concept used across geoscience to describe water-limited environments, yet the scientific community currently uses multiple contradictory approaches to communicate aridity science. Here, we present the scope of aridity definition divergence, showing that out of 1000+ assessed studies aridity, A, is commonly defined as both the ratio of precipitation, P, to evaporative potential, EP, as A = P/EP (32 % of papers) and as its mathematical reciprocal A = EP/P (23 % of papers), or is not defined at all (29 % of papers). Based on this split between opposing definitions, we suggest standardization of the meaning of aridity for more effective interdisciplinary communication, accurate modeling, and metanalyses pertaining to water scarce regions.