In order to determine icing conditions and to make icing forecast information it is required to know the air content of liquid water, Liquid Water Content (LWC) and droplet size, Median Volume Diameter (MVD).


Unfortunately, these parameters are very difficult to measure and therefore they areestimated today. Of course it is desirable to measure these para,eters to ensure that the correct information is obtained from ice aggregation calculations and that correct icing forecasts can be done.

It is known that water absorbs infrared light and by utilizing  the infrared absorbation and the latest sensor technology for infra red imaging it should be possible to find a method that can determine LWC and MVD. As described, there is a high demand for mesurements of LWC and MVD to determine icing conditions. Research to find a reliable method of measuring LWC and MVD should thus be prioritized.

The project intends to develop a direct method for determining the air content of liquid water, LWC, and droplet size, MVD. These parameters are critical for the meteorological conditions that govern the icing process, and tools to directly determine them missing today. By being able to measure the parameters of both the calculations of glaciation and new tools for measuring the ice can be developed.

The method will use imaging technologies and advanced sensors, and will be  tested in a climate chamber. The goal is that the instrument should work in real conditions and be able to be commercialized. The performers are Mid Sweden University and COMBITECH that produces measuring instruments for wind power.

Fältstudie i Klövsjö
FOGGY - A Vision sensor for environmental monitoring in cold climate. The FOGGY sensor is a prototype instrument for measurement of Liquid Water Content (LWC) and Median Volume Diameter (MVD).

Research group


Project Leader
Benny Thörnberg

Staffan Rydblom

Project period



Statens Energimyndighet