Hi Bass and readers,
Is there a treble tuba? (;->)
Sorry OM, the term "ground clutter" does not apply, modern radars are computer driven and programmed to ignore ground reflections that would otherwise clutter the display. The beauty of Doppler radar is it's programmed to detect motion so it automatically ignores ground clutter and cloud reflections.
Speaking of which, before Doppler I used to see a strange cloud like image at the tip of Sandy Hook (NJ) and never figured out what it was. There is nothing there besides a bunch of low wooden buildings at Fort Hancock now deactivated. Hmmmm, does the word "military" mean anything to you? (;->)
A temperature inversion forms a boundary layer in the troposphere which forms a duct between it and the ground which the signal travels through like a waveguide, bouncing between the boundary layer and the ground all the way. Radar does not detect this layer but is affected by it, mariners are sometimes confused by distant "ghost" images much like a mirage.
"Tropo" can sometimes be predicted by looking at a weather map, most often it's caused by an approaching cool front when cool air slips under warm surface air forming the boundary layer. On the other hand approaching warm air can slide up and over cooler surface air again forming the boundary.
In coastal areas a cool onshore breeze can slip under warm air, our ducting along the Eastern Seaboard is legendary. It's often unpredictable due to wind shifts and can happen on and off all day while it normally happens during the evening or early morning hours due to cyclic solar heating and cooling effects. BTW, I can see things in the clouds, when they're coming from the west and there's a cool breeze off the ocean distant Coast Guard stations are often heard.
Being a ham operating on VHF and UHF frequencies at the Jersey Shore I often enjoy tropo and have worked stations from the Canadian Maritimes to the Caribbean and sometimes over 150 miles inland due west. No "super station" here, only 50W VHF and 25W UHF into a vertical @ 80' AMSL and the antenna does double duty, works great on the scanner.
