Unusual appearance of mother‐of‐pearl clouds above El Calafate, Argentina (50°21′S, 72°16′W)
Kaifler, Bernd
Kaifler, Natalie
Rapp, Markus
Wildmann, Norman
Garhammer, Markus
Ohlmann, Klaus
Payne, James M.
Sandercock, Morgan
Austin, Elizabeth J.
DOI: https://doi.org/10.23689/fidgeo-4055
Kaifler, Natalie; 1 Institut für Physik der AtmosphäreDLR OberpfaffenhofenOberpfaffenhofen, Germany
Rapp, Markus; 1 Institut für Physik der AtmosphäreDLR OberpfaffenhofenOberpfaffenhofen, Germany
Wildmann, Norman; 1 Institut für Physik der AtmosphäreDLR OberpfaffenhofenOberpfaffenhofen, Germany
Garhammer, Markus; 2 Meteorologisches InstitutLudwig‐Maximilians‐Universität MünchenMunich, Germany
Ohlmann, Klaus; 3 Mountain Wave Project e. VGrand TerrusMontclus, France
Payne, James M.; 4 The Perlan Project, IncBeaverton Oregon USA
Sandercock, Morgan; 4 The Perlan Project, IncBeaverton Oregon USA
Austin, Elizabeth J.; 4 The Perlan Project, IncBeaverton Oregon USA
Abstract
Visual observations from the ground and from a glider soaring in the lowermost stratosphere revealed the existence of stratospheric mother‐of‐pearl clouds above El Calafate in the lee of the Andes on 11 September 2019. The appearance of these clouds is rather unusual considering the time – end of the austral winter – and the location at about 50°S, being far away from Antarctica. This paper presents the available observations and describes the overall meteorological situation that was related to the earliest sudden stratospheric warming recorded so far in the Southern Hemisphere. By using high‐resolution numerical simulations, we show evidence of mountain waves propagating up to the stratosphere that are responsible for generating the localised cold stratospheric temperature anomalies required for ice cloud formation. Snapshots of a mother‐of‐pearl cloud from the camera installed at the PERLAN 2 aircraft's tail wing.
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