UAV SAR L band (1.6 GHz) ~20cm – In this frequency, insensitive to grain size (Shi & Dozier) –...

Post on 19-Jan-2016

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UAV SAR

• L band (1.6 GHz) ~20cm– In this frequency, insensitive to grain size (Shi & Dozier)

– Sensitive to density, liquid water content– Need dielectric constants

Capacitec Probe

• 16, 32, or 64kHz• Claims to accurately measure snow density

and liquid water content.

Permittivity of ice and water (Stacheder 2005)

Capacitec probe UAV SAR (L-Band)

Permittivity (real) vs density for dry snow (Matzler 1996)

• Around 1GHz• So if we know density

from the probe, can get permittivity

Effect of water content• W is water content• So if we know water content and density, can

get dielectric constants

Permanent dataloggers at GPS stations

• Use soil moisture probes to measure dielectric constants of snow and log for 2 weeks?

• These are RF capacitance probes, but unclear if can get more than just moisture (need density also)