In meteorology, how is fog detected using satellite, radar and lidar?

Question

Please provide me with the most detailed explanation but please make it simple!

Answer 1

Fog is a cloud at the surface. When I do a forecast I use visible satellite to do a fog forecast. Although there is a problem with this method, if the sun has not come up yet then visible satellite is pretty much worthless. To get around this you have to go by a couple of other methods. If you have access to computer models these help a lot. I tend to look at relative humidity at the surface and near the surface, 10 meter winds, and other mixing products (ie. vorticity). Other than that you have to use surface observations.

When comes to the other methods that you ask about:
One could use radar and lidar to look for fog. Radar and lidar works by sending out signals and these signals bounce off of moisture and return to the radar where the data is then turned into pictures. The downside to these methods is that radar is primarily used to look above the surface. So it may or may not pick up on fog. Also when the temperature approaches the dew point (or when the relative humidity value rises), which usually occurs overnight and in the morning hours (which is when fog forms), radar picks up on this added moisture and sends back false readings (or ground clutter).

But if I had to pick one of the three things that you have listed to do fog forecasts I would use satellite over the other two.

Answer 2

Radar detects moister, itll be able to find fog. Satelite views images of anything in its lens. Its basically a camera. Itll easily find fog, just like it can take pictures of hurricanes.

I cant help you on lidar, because ive never heard of it.

Answer 3

by the amount of moisture that the fog emits.