1. Highly Active Ice-Nucleating Particles at the Summer North Pole
- Author
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Karolina Siegel, Michael P. Adams, Julika Zinke, Ian M. Brooks, Heini Wernli, Jutta Vüllers, Mark D. Tarn, Luisa Ickes, Caroline Leck, Matthew Salter, Paul Zieger, Sebastien N. F. Sikora, Linn Karlsson, Benjamin J. Murray, Julia Schmale, and Grace C. E. Porter
- Subjects
North pole ,0303 health sciences ,010504 meteorology & atmospheric sciences ,Atmospheric sciences ,01 natural sciences ,Physics::Geophysics ,03 medical and health sciences ,13. Climate action ,Radiative transfer ,Environmental science ,Astrophysics::Earth and Planetary Astrophysics ,14. Life underwater ,Supercooling ,Physics::Atmospheric and Oceanic Physics ,030304 developmental biology ,0105 earth and related environmental sciences - Abstract
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., Journal of Geophysical Research: Atmospheres, 127 (6), ISSN:0148-0227, ISSN:2169-897X
- Published
- 2022