OPTICE (OPTics for ICE and snow) is an interdisciplinary research initiative focused on investigating the optical characteristics of airborne dust found in Alpine snow.
On a global scale, mineral dust is the dominant contributor to atmospheric particulate mass. Composed of tiny mineral particles lifted from arid and semi-arid regions by wind-driven processes, dust can significantly impact glaciers by diminishing their reflectivity and accelerating melting. Additionally, it influences the snowpack, leading to the formation of melt-freeze crusts and fragile hoar crystal layers. Conversely, snow and ice cores serve as invaluable records for reconstructing past and present atmospheric compositions. Their analysis not only helps assess environmental changes caused by human activity but also supports studies on albedo variations and avalanche risk assessment.
The OPTICE project is centered on examining snow and ice cores from key Alpine locations at altitudes exceeding 3,000–3,200 meters over multiple years. Optical analysis of ice cores has been conducted at EuroCold, the European Cold Laboratory at the University of Milano-Bicocca. A key aspect of this research is the Single Particle Extinction and Scattering (SPES) method, pioneered by Marco Potenza. This innovative technique simultaneously measures two optical parameters, allowing for the assessment of additional particle characteristics such as shape and internal structure. Recent findings using this method have revealed notable changes in dust particle morphology over time, which directly influence atmospheric radiative transfer (Potenza et al., 2016, Nature Scientific Reports).
Radiative transfer plays a crucial role in climate science, as it dictates energy exchange within the atmosphere. According to the Intergovernmental Panel on Climate Change (2013), aerosol interactions significantly influence this process, making it essential to study both historical and current aerosol optical properties for accurate climate modeling.
At the snow-air boundary, dust particles and partially melted crystals undergo melting and refreezing cycles, forming crusts. When these crusts become embedded in the snowpack under strong temperature gradients, they promote the development of weak, faceted crystal layers—an important factor in snowpack instability and avalanche formation. Understanding dust size distribution and composition is therefore essential for improving avalanche forecasting.
Accurate assessments of dust within the snowpack also enhance predictions of snowmelt and enable better resource management. This is particularly beneficial for ski resorts optimizing artificial snow production and for water management agencies forecasting seasonal water availability from melting glaciers and snowfields.
As a multidisciplinary endeavor, OPTICE aims to analyze the optical properties of dust, snow, and ice crystals within snowpacks and ice cores. The project brings together experts from diverse fields, reinforcing the idea that an integrated scientific approach is necessary to comprehend the complexities of climate systems and the cryosphere.
Beyond research, OPTICE is dedicated to public outreach, using videos, educational materials, interviews, and conferences to enhance climate awareness. By engaging with schools and the broader public, the project seeks to foster a deeper understanding of the cryosphere and the urgent challenges posed by climate change—before Alpine snow and ice become a thing of the past.
The Aosta Valley in northwestern Italy serves as a vital research site, offering well-preserved glacial deposits that provide long-term records of snow and its contained particles. The primary study area is Rutor Glacier, where a six-year archive of snow cores has been collected and is currently under analysis. In 2016, additional data was gathered near Dent du Géant, where summer snow cover exhibited unique characteristics. Other research locations include Col Peuterey and Dôme du Goûter (Mont Blanc), where year-round temperature conditions align with the project’s objectives. Field tests and routine operations are frequently conducted at Plateau Rosa, Refuge Torino, Punta Indren, and nearby glaciers, accessible via cableways. Additionally, specialized instruments will be installed at the CNR laboratory of Testa Grigia (Plateau Rosa) to support ongoing investigations.