Publication Date:
2023-07-11
Description:
In recent decades there has been a slow paradigm shift in the representation of snow in radiative transfer and electromagnetic models, applied to both the optical and microwave domains. Representing snow on the ground in these models was typically treated as for clouds, snow was assimilated to a collection of ice particles randomly distributed in the air. The main input parameters – snow grain size, grain shape and density – were commonly measured by practitioners, and snow evolution models were predicting these quantities as well. Despite numerous successes, this approach began to show weaknesses as remote sensing observations increased. In addition, the micro-computed tomography provided detailed 3D images that highlighted the complexity of the snow microstructure, leading to clear evidence that snow is not composed of independent grains, thus calling into question the notions of grain size and particle shape. Nevertheless, in the last decades, many efforts have been made to adapt the particle approach to the admittedly complex microstructure, leading to the widespread adoption of the optical diameter in the optical range, or the sticky hard sphere model in the microwaves. Radiative model and evolution models were easily patched to deal with these new concepts. Current research is moving away from the idea of grains. Thanks to advances in the random heterogeneous materials theory, new well-defined quantities are emerging to describe the “size” and the “shape” of snow. In this poster, we present these recent advances.
Language:
English
Type:
info:eu-repo/semantics/conferenceObject
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