The onset and growth of the 2018 Martian Global Dust Storm

TL;DR

This paper analyzes the initial development and expansion of the 2018 Martian Global Dust Storm using ground-based visual images, revealing its unique northern hemisphere onset and detailed expansion velocities.

Contribution

First detailed analysis of the 2018 Martian GDS onset and expansion using ground-based imagery, highlighting its northern hemisphere initiation and expansion dynamics.

Findings

Dust storm initiated in the Northern Hemisphere.

Storm expanded southwards at 5 m/s.

Dust reached southern latitudes and polar regions.

Abstract

We analyze the onset and initial expansion of the 2018 Martian Global Dust Storm (GDS 2018) using ground-based images in the visual range. This is the first case of a confirmed GDS initiating in the Northern Hemisphere. A dusty area extending about 1.4x10e5 km^2 and centered at latitude +31.7{\deg} $\pm$ 1.8{\deg} and west longitude 18{\deg} $\pm$ 5{\deg}W in Acidalia Planitia was captured on 30 and 31 May 2018 (Ls = 184.9{\deg}). From 1 to 8 June, daily image series showed the storm expanding southwards along the Acidalia corridor with velocities of 5 m/s, and simultaneously progressing eastwards and westwards with horizontal velocities ranging from 5 to 40 m/s. By 8 June the dust reached latitude -55{\deg} and later penetrated in the South polar region, whereas in the North the dust progression stopped at latitude +46{\deg}. We compare the onset and expansion stage of this GDS with the previous confirmed storms.