The phrasing in that web article is confusing. In particular they say water is very *absorbing* in the near infrared, which should mean something containing water should not reflect in the near infrared, but the phrasing seems to be saying materials containing water will *reflect* strongly in the near infrared.

However, I have found some articles that suggest it should be possible to distinguish between the phases of water in visible to near-infrared wavelength observations:

Spectroscopy of Solid, Liquid and Vapor Water Phases.
"It is only from radiometric measurements, with sufficient spectral resolution, that atmospheric constituents (a complex mixture of absorbers and scatterers) can be identified and quantified. Water, being the most important absorbing species, is present in three phases. Broadband sensors integrate the effect of all three phases, while spectral measurements allow the absorption of each phase to be separately quantified. If atmospheric parameterizations are to be based on physical principles, spectral measurements that allow quantification of the three phases of water are required."
http://www.asdi.com/asdi_ap_en_apnts_w_fsp.html

Cloud Water Phases.
"The deployment of a spectroradiometer covering the spectrum in the 1.0-2.5 µm region makes it possible to identify the three phases of water in the atmospheric column. Primary water vapor absorption bands are centered at 0.94, 1.13, 1.37, 1.9 µm, while unsaturated liquid water bands are centered at 1.0 and 1.2 µm. A strong ice feature is found at 1.5 µm. Because the absorption features of the three phases of water are offset from one another, and because there are accurate models for the absorption features, the irradiance spectra can be simultaneously analyzed for the column abundance of the different phases.
"Gao and Goetz (1990, 1991) showed that, by using a non-linear least squares method, total column precipitable water vapor and equivalent liquid water thickness in vegetation could be obtained simultaneously on a pixel basis in Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data. The absolute value of the precipitable water vapor was confirmed to be accurate to 5% by AVIRIS overflights of upward-lookingupward looking microwave radiometers (Gao et al, 1992)."
http://www.asdi.com/asdi_ap_en_apnts_s_fsp.html

DISCRIMINATING BETWEEN WATER AND ICE CLOUDS USING NEAR-INFRARED AVIRIS MEASUREMENTS.
http://makalu.jpl.nasa.gov/docs/workshops/00_docs/Knap_web.pdf

MEASURMENT OF THE SPECTRAL ABSORPTION OF LIQUID WATER IN MELTING SNOW WITH AN IMAGING SPECTROMETER.
http://makalu.jpl.nasa.gov/docs/workshops/95_docs/26.PDF

Bob Clark