资源环境科技发展态势分析平台

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 1.4x10(5) km(2) and centered at latitude +31.7 degrees +/- 1.8 degrees and west longitude 18 degrees +/- 5 degrees W in Acidalia Planitia was captured on 30 and 31 May 2018 (Ls = 184.9 degrees). From 1 to 8 June, daily image series showed the storm expanding southward along the Acidalia corridor with velocities of 5 m/s and simultaneously progressing eastward and westward with horizontal velocities ranging from 5 to 40 m/s. By 8 June the dust reached latitude -55 degrees and later penetrated in the South polar region, whereas in the North the dust progression stopped at latitude approximately +46 degrees. We compare the onset and expansion stage of this GDS with the previous confirmed storms.