Which type of AIRMET indicates moderate icing conditions?

AIRMET Zulu is specifically used to indicate moderate icing conditions. This type of AIRMET focuses on the potential for significant icing in clouds and has a direct impact on aircraft operations, especially for those flying in instrument meteorological conditions (IMC). Pilots should take AIRMET Zulu seriously as it provides crucial information needed for flight planning and operational safety, particularly for aircraft that may not typically handle icing conditions well.

In the context of other AIRMET types, AIRMET Tango is related to turbulence and is not concerned with icing phenomena. AIRMET Sierra covers IFR conditions and mountain obscuration but does not specifically address icing either. AIRMET WA is not a standard designation in the context of AIRMETs issued by aviation authorities. Thus, AIRMET Zulu stands out as the only type that signals the need for caution regarding moderate icing conditions directly.