aire urbaine

The aire urbaine (not to be confused with English "urban area") is an INSEE (the national statistics office of France) statistical region comprising a couronne périurbaine commuter belt around a contiguous pôle urbain (urban area) urban core. The aire urbaine is a demographical unit the result of a quite literal methodology: drawn upon France's nation-wide map of interlocking commune municipalities, the aire urbaine has for its centre a pôle urbain (similar to a unité urbaine ("urban unit") - see note below) core of communes containing an interconnecting and unbroken urban growth; this centre forms a "pole of attraction" for a couronne périurbaine ("periurban ring" or commuter belt) communes having at least 40% of their resident populations commuting with the pôle urbain, or with other communes having the same relation to the pôle urbain. The result is a precise demographic map of a) a centre of urban growth and b) its socio-economic reach into the surrounding area.
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