On the track of the secret of giant dust particles
They have been puzzling the research community for a while: giant mineral dust particles. With diameters of 100 micrometers and more – the size of beach sand – they are multiple ten times larger than typical mineral dust particles. Despite their remarkable size and correspondingly large weight, these giant particles have been found to be able to travel over thousands of kilometers in the atmosphere. How this is possible is to date unknown. Hypotheses about processes which could contribute to keeping the particles aloft have been put forward, for example electrical charge, particle shape, turbulent eddies, and favorable weather conditions, such as strong upward wind velocities in thunderstorms. However, confirming or rejecting any of these hypotheses has been difficult so far.
In an international field campaign named J-WADI (Jordan Wind erosion And Dust Investigation), the Helmholtz Young Investigator Group “Mineral Dust” aims to take the next step towards unraveling the mystery of giant dust particles. Combining novel aerosol instrumentation, part of which were specifically further-developed to measure giant dust, with advanced meteorological measurements using the KITcube observational system, one of the goals of the campaign is to quantify how many giant dust particles are emitted and how many get to heights that might enable them to enter long-range transport. Besides particle size, the dust mineralogical composition is another focus of the campaign. The relative abundance of different minerals in dust particles influences their effect upon climate.
The campaign is co-organized between IMK-TRO (principal investigator Dr. Martina Klose) and the Barcelona Supercomputing Center (principal investigator Dr. Carlos Pérez García-Pando) in collaboration with the University of Jordan and brings together prime mineral dust experts from multiple institutions across Europe, Jordan, and the USA. In September 2022, the group installs state-of-the-art ground-based meteorological and aerosol instrumentation – both in situ and remote sensing – in the desert north of Wadi Rum in Jordan. If successful, the campaign will provide data of dust emission and near-surface transport at an unprecedented level of detail and comprehensiveness.
More detailed information and J-WADI updates can be found here: https://www.imk-tro.kit.edu/english/11800.php