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arXiv · 1409.5068

Compressive Earth Observatory: An Insight from AIRS/AMSU Retrievals

Abstract

We demonstrate that the global fields of temperature, humidity and geopotential heights admit a nearly sparse representation in the wavelet domain, offering a viable path forward to explore new paradigms of sparsity-promoting data assimilation and compressive recovery of land surface-atmospheric states from space. We illustrate this idea using retrieval products of the Atmospheric Infrared Sounder (AIRS) and Advanced Microwave Sounding Unit (AMSU) on board the Aqua satellite. The results reveal that the sparsity of the fields of temperature is relatively pressure-independent while atmospheric humidity and geopotential heights are typically sparser at lower and higher pressure levels, respectively. We provide evidence that these land-atmospheric states can be accurately estimated using a small set of measurements by taking advantage of their sparsity prior.

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Ardeshir Mohammad Ebtehaj, Efi Foufoula-Georgiou, Gilad Lerman, Rafael Luis Bras. 2014-12-30. Compressive Earth Observatory: An Insight from AIRS/AMSU Retrievals. https://doi.org/10.1002/2014gl062711

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