FATIMA-IF

Fatima Ice Fog Campaign 2025

15 November 2025 - 7 December 2025

Lead Scientist: Harindra Fernando

Observatory: NSA (North Slope of Alaska)

The Fatima-IF campaign at the U.S. Department of Energy (DOE) North Slope of Alaska ARM observatory at Utqiaġvik (formally Barrow), to take place from 15 November to 6 December, 2025, is designed to study the nexus of ice fog (IF) microphysics and environmental turbulence, including capturing of bio-physicochemical processes and influence of the nearby Arctic Ocean. IF is the least understood type of fog, given the measurement and logistical difficulties of working in harsh, frigid environments and intricacies of multi-scale processes underpinning IF environs. When IF occurs, all moisture in the air condenses on ice nuclei, thus contributing to extinction of radiation and low visibility conditions. IF has pervasive implications on infrastructure, navigation [in the new Arctic], transportation, commerce, national security, high-latitude ecosystems, and rapid changes in polar environments. The Fatima-IF campaign is a part of the Fatima project funded by the US Office of Naval Research Marine Meteorology and Space Weather Program as a Multidisciplinary University Research Initiative (MURI). Fatima-IF is the last of the three Fatima field campaigns, the first two successfully conducted in the Grand Banks and Yellow Sea, in 2022 and 2023, respectively, focusing on marine fog.

Fatima-IF will be collaboratively conducted with Sandia National Laboratories under the DOE ARM User Facility. A myriad of remote-sensing platforms and in situ sensors available at the NSA site, supplemented by guest instruments from University of Notre Dame, Airforce Institute of Technology, Naval Postgraduate School, Ontario Technical University, Pacific Northwest National Laboratory, University of Alaska, University of Albany, University of California (Scripps) and University of Utah will be used for data gathering. Fatima-IF intends to study: (i) nucleation and ice crystal formation during IF events in the presence of low boundary-layer clouds, and the role of turbulence therein, (ii) how air-sea fluxes impact coastal IF formation, (iii) biophysicochemical properties of nucleating aerosols and their impact on optical properties of IF, (iv) microphysical parameterizations for IF, including the efficacy of existing parameterizations, and (v) vertical profiles of IF microphysical properties, which have been essentially unavailable hitherto. Identification of new processes and phenomena, development and validation of parameterizations for numerical weather prediction models, and application of high-resolution models delving into IF microphysics will also be pursued.