Applicant

Dr. Sabrina Schnitt
Universität zu Köln
Department für Geowissenschaften
Institut für Geophysik und Meteorologie
Pohligstraße 3
50969 Köln

Project description

The Antarctic climate system strongly depends on the properties and changes of the atmospheric water cycle and its components: water vapor, clouds, and precipitation. Yet, the representation of the water cycle components and processes constitutes a major uncertainty in current projections of the future climate, including a lack of understanding of interaction with changing sea-ice. Despite their importance, existing water vapor, cloud, and precipitation observations are either limited to few ground-based stations in complex orographic surroundings, or to satellite observations with coarse horizontal resolution and a blind zone in the lowest kilometer of the troposphere. Based on airborne operations from Neumayer Station III as central part of Antarctica InSync, our goal is to answer the following questions: (i) How variable are conditions on the Ekström ice shelf around Neumayer Station III, and how does variability depend on surface, orographic and synoptic conditions? (ii) How large is sub-scale variability of water vapor, clouds, and precipitation in state-of-the-art reanalysis and satellite products? (iii) Compared to their Arctic counterparts, how do mixed-phase clouds differ in properties and dependencies, and does state-of-the-art reanalysis represent these differences? We will deploy a synergy of cutting-edge remote sensing instrumentation aboard the Alfred Wegener Institute’s (AWI) Polar aircraft to answer these questions. Our synergistic remote sensing instrumentation includes multi-frequency cloud radars, microwave radiometer, lidar, spectral and broadband radiation measurements, and dropsondes. By applying existing and novel synergistic retrieval algorithms, we will create a benchmark dataset of water vapor, clouds, and precipitation. This dataset will not only allow the statistical evaluation of component properties using a quasi-Lagrangian sampling strategy, but will also assess their representation in widely used reanalysis products. VACANT will deliver unprecedented airborne observations of the Antarctic atmospheric water cycle at high temporal and spatial resolution over the Antarctic ocean and continent. Our measurements and analyses promise to fill current critical gaps in the understanding of central processes driving the Antarctic water cycle and its changes, including the interaction and influence of atmosphere on changing sea ice conditions.

DFG Programme Infrastructure Priority Programmes

Term since 2026