The forms of sand dust in the atmosphere have been specified: remote measurements and climate models incorrectly assume dust to be almost spherical
Sand dust of Sahara rising into the atmosphere on February 22, 2017 under the influence of winds, by the Suomi NPP satellite. The figure also shows two magnified dust particles from the research data. Satellite image: Antti Lipponen. Dust particle images: Konrad Kandler.Researchers brought together samples of mineral dust collected from the atmosphere during several campaigns and measurements. The shape of the dust particles was determined by measuring the maximum diameter of the dust and the perpendicular height against it. The researchers noticed that on average, the largest diameter of dust is about 5 times larger than the height of the particle.
This discovery now allows researchers to explain the intercontinental transport of dust. The discovery may also be significant in the interpretation of remote measurements.
Further information:
Head of Group Hannakaisa Lindqvist, Finnish Meteorological Institute, hannakaisa.lindqvist@fmi.fi Senior scientist Timo Nousiainen, Finnish Meteorological Institute, timo.nousiainen@fmi.fi Reference: Huang, Y., Kok, J. F., Kandler, K., Lindqvist, H., Nousiainen, T., Sakai, T., et al. (2020). Climate models and remote sensing retrievals neglect substantial desert dust asphericity. Geophysical Research Letters, 47, e2019GL086592. https://doi.org/ 10.1029/2019GL086592