Ice and supercooled water detection system

A method for detecting ice within an area of interest, said method comprising:

• measuring a first radiance level of the area of interest at a first spectral band in the range of about 2.05 μm to about 2.15 μm;
• measuring a second radiance level of the area of interest at a second spectral band in the range of about 2.15 μm to about 2.30 μm;
• calculating a radiance ratio of said first radiance level and said second radiance level;
• and
• determining whether said radiance ratio is within a predetermined critical radiance ratio range,
• if said radiance ratio is within said predetermined critical radiance ratio range then determining if a specular reflection is present by determining if said first radiance is greater than a predetermined critical radiance and outputting an ice-present warning.

A method for detecting supercooled liquid water droplets within an area of interest, said method comprising:

• measuring a first radiance level of the area of interest at a first spectral band in the range of about 2.05 μm to about 2.15 μm;
• measuring a second radiance level of the area of interest at a second spectral band in the range of about 2.15 μm to about 2.30 μm;
• calculating a radiance ratio of said first radiance level and said second radiance level;
• and
• determining whether said radiance ratio is within a predetermined critical radiance ratio range,
• if said radiance ratio is within said predetermined critical radiance ratio range then measuring a temperature of the area of interest and determining if said temperature is within a predetermined critical temperature range and outputting a supercooled-liquid-water-droplets-present warning.

A method for detecting supercooled large droplets (SLD) within an area of interest, said method comprising:

• measuring a first radiance level of the area of interest at a first spectral band in the range of about 2.05 μm to about 2.15 μm;
• measuring a second radiance level of the area of interest at a second spectral band in the range of about 2.15 μm to about 2.30 μm;
• calculating a radiance ratio of said first radiance level and said second radiance level;
• and
• determining whether said radiance ratio is greater than a predetermined critical radiance ratio,
• if said radiance ratio is within said predetermined critical radiance ratio then calculating a droplet effective radius and determining if said droplet effective radius is greater than a predetermined critical droplet radius and outputting a supercooled-large-droplets-present warning.