Earth Institute Research Projects

Collaborative Research: Closing the Gaps in Climate Models' Surface Albedo Schemes of Processes Award Abstract #1713072 Collaborative Research: Closing the Gaps in Climate Models' Surface Albedo Schemes of Processes

Lead PI: Marco Tedesco

Unit Affiliation: Marine Geology & Geophysics, Lamont-Doherty Earth Observatory (LDEO)

September 2017 - August 2020
Arctic ; Greenland
Project Type: Research

DESCRIPTION: Surface albedo is a measure of the percentage of solar radiation that is reflected by a medium. The higher (lower) the albedo, the lower (higher) is the amount of solar energy absorbed by the medium. Albedo plays a critical role on the Greenland Ice Sheet, where absorbed solar radiation is the dominant driver of surface melt during summer. The evolution of albedo on the Greenland Ice Sheet is primarily driven by changes in snow grain size, the presence of liquid water on the surface, the exposure of bare ice, and the presence of light-absorbing impurities in the snow and ice. Such impurities include soot, dust, and biological constituents like bacteria and algae. Interactions between biological impurities and snow physical processes (e.g., metamorphism and melt redistribution) are important because they can drive positive feedbacks in which total melt is amplified. Despite their importance, these processes relating biological constituents to snow and ice evolution are currently either absent or poorly represented in models used to simulate current estimates and future projections of the contribution of Greenland to sea level rise. Through an interdisciplinary and collaborative effort, this project will integrate state of the art knowledge of how biological activity impacts albedo into climate models. This will help reduce uncertainties of the contribution of Greenland to sea level rise and will also improve our understanding of interactions between the ice sheet and the atmosphere. The regional climate and Earth System models that will be applied in our study are open-source models, such as e.g., the Community Earth System Model). Model improvements that are implemented will be released for use by other researchers in a timely way. The project includes the involvement of a postdoctoral fellow, and hence training of young investigators to address complex and yet crucial science questions through an interdisciplinary effort. Results from this project will be communicated to the media and public, thereby promoting deeper knowledge of the processes affecting the surface mass balance of the Greenland Ice Sheet.


National Science Foundation (NSF)





Alexander, P. M. and LeGrande, A. N. and Fischer, E. and Tedesco, M. and Fettweis, X. and Kelley, M. and Nowicki, S. M. and Schmidt, G. A.. "Simulated Greenland Surface Mass Balance in the GISS ModelE2 GCM: Role of the Ice Sheet Surface," Journal of Geophysical Research: Earth Surface, v.124, 2019. doi:10.1029/2018JF004772 Citation details

Wang, Shujie and Tedesco, Marco and Xu, Min and Alexander, Patrick M.. "Mapping Ice Algal Blooms in Southwest Greenland From Space," Geophysical Research Letters, v.45, 2018. doi:10.1029/2018GL080455 Citation details


snow grain size education surface melt surface albedo science communication surface mass balance


Modeling and Adapting to Future Climate