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Oceanography and Atmospheric Sciences and Meteorology

Alan Z Liu

Selected Works

2014

Articles 1 - 2 of 2

Full-Text Articles in Earth Sciences

Measuring Eddy Heat And Constituent Fluxes With High-Resolution Na And Fe Doppler Lidars, Chester S. Gardner, Alan Z. Liu Sep 2014

Measuring Eddy Heat And Constituent Fluxes With High-Resolution Na And Fe Doppler Lidars, Chester S. Gardner, Alan Z. Liu

Alan Z Liu

Vertical transport by turbulent mixing plays a fundamental role in establishing the thermal and
constituent structure of the upper mesosphere and lower thermosphere (MLT). Because of observational
challenges, eddy heat, constituent, and momentum fluxes, and the associated coefficients for thermal (kH),
constituent (kzz), and momentum (kM), diffusion have not been well characterized in the MLT. We show that
properly configured Na and Fe Doppler lidars, with sufficient resolution to observe the turbulence-induced wind,
temperature, and density fluctuations, can make direct measurements of eddy …


Inferring The Global Cosmic Dust Influx To The Earth’S Atmosphere From Lidar Observations Of The Vertical Flux Of Mesospheric Na, Chester S. Gardner, Alan Z. Liu, Dan Marsh, Wuhu Feng, John Plane Aug 2014

Inferring The Global Cosmic Dust Influx To The Earth’S Atmosphere From Lidar Observations Of The Vertical Flux Of Mesospheric Na, Chester S. Gardner, Alan Z. Liu, Dan Marsh, Wuhu Feng, John Plane

Alan Z Liu

Estimates of the global influx of cosmic dust are highly uncertain, ranging from 0.4110 t/d. All
meteoric debris that enters the Earths atmosphere is eventually transported to the surface. The downward
fluxes of meteoric metals like mesospheric Na and Fe, in the region below where they are vaporized and
where the majority of these species are still in atomic form, are equal to their meteoric ablation influxes,
which in turn, are proportional to the total cosmic dust influx. Doppler lidar measurements of mesospheric Na
fluxes made throughout the …