The Reverse IFF system allows an aircraft providing close-air support (CAS) to interrogate a target area using its existing IFF transponder at 1090 MHz rather than the standard 1030 MHz.

Within about a millimeter of the water, air temperature is close to that of the surface water, and the air is nearly saturated with water vapor.

Since a plant uses it up in the air around, the plant needs moving air to bring more CO2 close to its surface!