Publications de Michael Lehning

Retrieval of Surface Solar Radiation through Implicit Albedo Recovery from Temporal Context

Devis Tuia, Michael Lehning, Yael Frischholz

To retrieve Surface Solar Radiation (SSR) from satellite images, a baseline reflectance of the observed ground in clear-sky conditions, also called background reflectance, is necessary to distinguish atmospheric absorption and scattering effects from surfa ...

2025

Towards a physically and microstructure-based equation for the evolution of the specific surface area in snow

Michael Lehning

The specific surface area (SSA) of snow is a critical structural quantity that controls snow properties and constantly evolves over time. An accurate understanding and modeling of the dynamical evolution of the SSA is thus of primary importance for snowpac ...

2025

Banner Cloud Formation at the Matterhorn: Measurements versus Large-Eddy Simulations

Michael Lehning, Wolf Hendrik Huwald, Brandon Jacobus Adrianus Van Schaik

Banner clouds are clouds in the lee of steep mountains or sharp ridges on otherwise cloud-free days. Previous studies identified key mechanisms and preferred flow conditions on the basis of idealized Large-Eddy Simulations, but it remained unclear to what ...

American Meteorological Society2025

The MatterHEX Experiment – Investigating Atmospheric Flow Patterns in Highly Complex Terrain Related to Banner Cloud Formation

Michael Lehning, Wolf Hendrik Huwald, Brandon Jacobus Adrianus Van Schaik

Orographic clouds typically form on the windward side of a topographic barrier when approaching air is cooled as it is lifted, and moisture condenses into cloud droplets. Under special conditions, however, clouds can appear on the leeward side of a mountai ...

American Meteorological Society2025

Governing Processes of Structure-Borne Snowdrifts: A Case Study at Neumayer Station III

Michael Lehning, Océane Hames

The genesis of snowdrifts and its governing processes are not fully understood. In Antarctica, understanding snow movement is crucial for assessing ice sheet mass balance and tackling logistical challenges related to human infrastructure. So far, extensive ...

2025

Parameterizing Snow Sublimation in Conditions of Drifting and Blowing Snow

Michael Lehning, Christophe Moser, Armin Sigmund

Snow transport favors strong sublimation and may therefore have an important effect on the surface mass balance of polar and high‐mountain regions. Recently, small‐scale models such as large‐eddy simulation (LES) with Lagrangian snow particles have improve ...

American Geophysical Union (AGU)2025

Influence of air flow features on alpine wind energy potential

Michael Lehning, Wolf Hendrik Huwald, Franziska Gerber, Jérôme François Sylvain Dujardin, Fanny Kristianti

Wind energy is one of the potential options to fill the gap in renewable energy production in Switzerland during the winter season when the energy demand exceeds local production capacities. With likely further rising energy consumption in the future, the ...

Frontiers Media Sa2024

Impact of intercepted and sub-canopy snow microstructure on snowpack response to rain-on-snow events under a boreal canopy

Michael Lehning, Daniel Nadeau, Nander Wever, Adrien Michel, Benjamin Bouchard

Rain-on-snow events can cause severe flooding in snow-dominated regions. These are expected to become more frequent in the future as climate change shifts the precipitation from snowfall to rainfall. However, little is known about how winter rainfall inter ...

2024

Snowfall deposition in mountainous terrain: a statistical downscaling scheme from high-resolution model data on simulated topographies

Michael Lehning

One of the primary causes of non-uniform snowfall deposition on the ground in mountainous regions is the preferential deposition of snow, which results from the interaction of near-surface winds with topography and snow particles. However, producing high-r ...

Frontiers Media Sa2024

Intermediate complexity atmospheric modeling in complex terrain: is it right?

Michael Lehning, Dylan Stewart Reynolds, Michael Haugeneder

Dynamic downscaling of atmospheric forcing data to the hectometer resolution has shown increases in accuracy for landsurface models, but at great computational cost. Here we present a validation of a novel intermediate complexity atmospheric model, HICAR, ...

Frontiers Media Sa2024

Confirmation of the power gain for solar photovoltaic systems in alpine areas and across scales

Michael Lehning, Yael Frischholz

Introduction: High Alpine regions show a great potential for solar photovoltaic electricity production in winter due to the reflective properties of snow and the larger number of sun hours compared to lower urban and peri-urban regions. In countries with a ...

2024

Seasonal snow-atmosphere modeling: let's do it

Michael Lehning, Dylan Stewart Reynolds, Michael Haugeneder

Mountain snowpack forecasting relies on accurate mass and energy input information in relation to the snowpack. For this reason, coupled snow-atmosphere models, which downscale input fields to the snow model using atmospheric physics, have been developed. ...

COPERNICUS GESELLSCHAFT MBH2024

Identifying airborne snow metamorphism with stable water isotopes

Michael Lehning, Sonja Wahl

Abstract. Wind-blown snow is a frequent phenomenon in high-elevation and polar regions which impacts the surface energy and mass balance of these areas. Loose surface snow gets eroded and transported by wind, which influences the snow particles' physical p ...

Copernicus GmbH2024

A seasonal snowpack model forced with dynamically downscaled forcing data resolves hydrologically relevant accumulation patterns

Michael Lehning, Tobias Jonas, Dylan Stewart Reynolds

The Mountain snowpack stores months of winter precipitation at high elevations, supplying snowmelt to lowland areas in drier seasons for agriculture and human consumption worldwide. Accurate seasonal predictions of the snowpack are thus of great importance ...

Frontiers Media Sa2024

Turbulence in the Strongly Heterogeneous Near-Surface Boundary Layer over Patchy Snow

Michael Lehning, Dylan Stewart Reynolds, Michael Haugeneder

The near-surface boundary layer above patchy snow cover in mountainous terrain is characterized by a highly complex interplay of various flows on multiple scales. In this study, we present data from a comprehensive field campaign that cover a period of 21 ...

2024

Quantifying urban climate response to large-scale forcing modified by local boundary layer effects

Michael Lehning, Wolf Hendrik Huwald, Seyed Mahmood Hamze Ziabari

Over the past two decades, the joint manifestation of global warming and rapid urbanization has significantly increased the occurrence of heatwaves and the formation of urban heat islands in temperate cities. Consequently, this synergy has amplified the fr ...

2024

Profile measurements of snow transport and micrometeorology at Mizuho Station in Antarctica

Michael Lehning, Daniela Brito Melo, Armin Sigmund

This data was collected at Mizuho Station (44.315°E, 70.71°S, 2230 m a.s.l.), East Antarctica, from 30 September to 22 November 2000 during the 41st Japanese Antarctic research expedition. Vertical profiles of the horizontal mass flux and particle number s ...

EnviDat2024

Superconducting Gravimeter Observations Show That a Satellite-Derived Snow Depth Image Improves the Simulation of the Snow Water Equivalent Evolution in a High Alpine Site

Michael Lehning

The lack of accurate information on the spatiotemporal variations of snow water equivalent (SWE) in mountain catchments remains a key problem in snow hydrology and water resources management. This is partly because there is no sensor to measure SWE beyond ...

American Geophysical Union (AGU)2024

Influence of sun cups on surface albedo of wet Alpine snowpack

Michael Lehning, Mathias Thierry Pierre Bavay, Francesca Carletti

In high elevation Alpine areas, characterised by high snow accumulation and radiation-driven melt processes, the formation of peculiar ablation features called sun cups can be observed. Sun cups likely influence the energy and mass balance of the wet snowp ...

2024

Understanding snow saltation parameterizations: lessons from theory, experiments and numerical simulations

Michael Lehning, Daniela Brito Melo, Armin Sigmund

Drifting and blowing snow are important features in polar and high mountain regions. They control the surface mass balance in windy conditions and influence sublimation of snow and ice surfaces. Despite their importance, model representations in weather an ...

2024