Investigating impacts of dust events on atmospheric surface temperature in Southwest Asia using AERONET data, satellite recordings, and atmospheric models

TL;DR

This study examines how dust outbreaks influence atmospheric surface temperature in Southwest Asia, revealing that temperature generally decreases during dust events but can also increase, with effects lasting up to two days and varying by proximity to dust sources.

Contribution

It combines ground-based AERONET data, satellite observations, and atmospheric modeling to analyze the temporal effects of dust outbreaks on surface temperature in a specific region.

Findings

Temperature often decreases during dust outbreaks.

Temperature effects can last up to two days after peak dust activity.

Proximity to dust sources influences the synchronicity of dust and temperature variations.

Abstract

Dust layers have already been reported to have negative impacts on the radiation budget of the atmosphere. But the questions are: How does the atmospheric surface temperature change during a dust outbreak, and what is its temporal correlation with variations of the dust outbreak strength? We investigated these at selected AERONET sites, including Bahrain, IASBS, Karachi, KAUST Campus, Kuwait University, Lahore, Mezaira, Solar Village, in Southwest Asia, and Dushanbe in Central Asia, using available data from 1998 to 2024. The aerosol optical depth at 870 nm and the temperature recorded at each site are taken as measures of dust outbreak strength and atmospheric surface temperature, respectively. The Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model and the aerosol optical depths recorded by the Moderate Resolution Imaging Spectroradiometers (MODIS) on board the Aqua and Terra satellites are used to specify the sources of the dust outbreaks. Our investigations show that in most cases, the temperature decreases during a dust outbreak, but in a considerable number of cases, the temperature rises. Temperature changes are mostly less than 5 {\deg}C. We found that a dust outbreak may affect the temperature even up to two days after its highest intensity time. This effect is more profound at sites far from large dust sources, such as IASBS in northwest Iran. For sites that are located on either a dust source or very close to it, the temperature and dust optical depth vary almost synchronously.