Modifiers matching boundary:

• natural,
• physical,
• static,
• permanent,
• visual,
• administrative,
• hierarchical,
• solid,
• governing,
• atmospheric,
• historical,
• significant,
• geopolitical,
• smooth,
• sharp,
• semitransparent,
• syntactic,
• irregular,
• real,
• nonconducting,
• distinct,
• convenient,
• geographical,
• complex,
• political,
• horizontal,
• moving,
• artificial,
• geological,
• fixed,
• spatial,
• hard,
• jurisdictional,
• simple,
• hydraulic,
• spherical,
• logical,
• cultural,
• structural,
• smaller,
• rigid,
• hexagonal,
• critical,
• internal,
• crystalline,
• curved,
• clear,
• single,
• outer,
• front,
• oceanic,
• external,
• ecological,
• legal,
• nearby,
• biological,
• vertical,

Simple categories matching atmospheric:

• disturbance,
• phenomenon,
• surface,
• condition,
• instrument,
• process,
• compound,
• lifetime,
• region,
• property,
• circulation,
• gas,
• nitrogen,
• pressure,
• interference,
• air,
• action,
• contaminant,
• contamination,
• hazard,
• environment,
• impurity,
• science,
• issue,
• structure,
• particle,
• feature,
• weather,
• oxidizer,
• component,
• activity,
• constituent,
• boundary,
• quantity,
• event,
• object,
• composition,
• track,
• radiance,
• material,
• discharge,
• water,
• movement,
• storm,
• evolution,
• electricity,
• atom,
• variable,
• exposure,
• medium,
• substance,
• temperature,
• force,
• particulate,
• input,
• control,
• molecule,
• stuff,
• characteristic,
• aspect,
• oscillation,
• turbulence,
• energy,
• layer,
• precipitation,
• pollutant,
• effect,
• motion,
• quality,
• connection,
• topic,
• change,
• aggregate,
• deposit,
• research,
• sound,
• pollution,
• elements,
• influence,
• debris,
• salt,
• situation,
• entity,
• wave,
• agent,
• cyclone,
• state,
• study,
• aerosol,