Highly Active Ice-Nucleating Particles at the Summer North Pole
Artikel i vetenskaplig tidskrift, 2022
The amount of ice versus supercooled water in clouds is important for their radiative properties and role in climate feedbacks. Hence, knowledge of the concentration of ice-nucleating particles (INPs) is needed. Generally, the concentrations of INPs are found to be very low in remote marine locations allowing cloud water to persist in a supercooled state. We had expected the concentrations of INPs at the North Pole to be very low given the distance from open ocean and terrestrial sources coupled with effective wet scavenging processes. Here we show that during summer 2018 (August and September) high concentrations of biological INPs (active at >−20°C) were sporadically present at the North Pole. In fact, INP concentrations were sometimes as high as those recorded at mid-latitude locations strongly impacted by highly active biological INPs, in strong contrast to the Southern Ocean. Furthermore, using a balloon borne sampler we demonstrated that INP concentrations were often different at the surface versus higher in the boundary layer where clouds form. Back trajectory analysis suggests strong sources of INPs near the Russian coast, possibly associated with wind-driven sea spray production, whereas the pack ice, open leads, and the marginal ice zone were not sources of highly active INPs. These findings suggest that primary ice production, and therefore Arctic climate, is sensitive to transport from locations such as the Russian coast that are already experiencing marked climate change.
ice-nucleating particles
ice
Arctic
mixed-phase clouds
Författare
Grace C.E. Porter
University of Leeds
Michael P. Adams
University of Leeds
Ian M. Brooks
University of Leeds
Luisa Ickes
Chalmers, Rymd-, geo- och miljövetenskap, Geovetenskap och fjärranalys
Linn Karlsson
Stockholms universitet
Caroline Leck
Stockholms universitet
Matthew E. Salter
Stockholms universitet
Julia Schmale
Ecole Polytechnique Federale de Lausanne (EPFL)
Karolina Siegel
Stockholms universitet
Sebastien N.F. Sikora
University of Leeds
Mark D. Tarn
University of Leeds
Jutta Vüllers
University of Leeds
Karlsruher Institut für Technologie (KIT)
Heini Wernli
Eidgenössische Technische Hochschule Zürich (ETH)
Paul Zieger
Stockholms universitet
Julika Zinke
Stockholms universitet
Benjamin J. Murray
University of Leeds
Journal of Geophysical Research: Atmospheres
2169897X (ISSN) 21698996 (eISSN)
Vol. 127 6 e2021JD036059Ämneskategorier
Meteorologi och atmosfärforskning
Geologi
Multidisciplinär geovetenskap
DOI
10.1029/2021JD036059