Which of the following is NOT a problem encountered by radar systems in urban environments?

In urban environments, radar systems encounter various challenges due to the dense concentration of buildings, vehicles, and other structures that can interfere with radar signals. Multipath propagation occurs when radar signals reflect off surfaces and return to the receiver via multiple paths, leading to erroneous location data. Increased clutter from urban structures enhances noise and makes it difficult for radar systems to distinguish between actual targets and background noise. Reduced signal strength is also a concern due to the absorption and scattering of radar waves by buildings and other obstacles.

However, high altitude atmospheric conditions are typically not specific issues faced by radar systems in urban settings. Instead, these conditions can occur in more open or rural environments where the radar is operating at higher altitudes or under specific atmospheric conditions, such as temperature inversions or significant moisture, affecting radar performance differently. Therefore, while the other options depict challenges consistently experienced in urban radar operations, high altitude atmospheric conditions do not represent a direct urban-related problem.