A brief review of the data appears to suggest the following:
area_id - Appears to be a unique long integer ID number for the zone record
type - Unknown meaning. Values found: 0, 1
shape - The shape of the area 0 = Circle, 1 = Shape defined by Points data
lat - Latitude of the area center
lng - Longitude of the area center
radius - Diameter (if shape==0) of the circle
warning - Unknown. Values found: 0, 1. Most likely a boolean (no/yes=0/1). Appears most prominently 1 for things like Nuclear power stations, national parks and monuments.
level - Unknown. Values found: 0, 2. 0 appears most prominently for things like nuclear power stations, national parks, and monuments. 2 appears most prominently for airports.
disable - Unknown. Values found: 0, 1. Most likely a boolean. Odd one. Initially thought that it might disable the bird but Chicago O'Hare has disable 0 while Meigs field in Chicago has disable 1.
updated_at - Most likely a date/time stamp when the record was updated.
begin_at - Most likely a date/time when the record begins being active.
end_at - Most likely a date/time when the record stops being active.
name - Human readable title for the record
country - Country ID for the record I presume. Odd data though. "London Luton Airport" lists country 826 while "London City Airport" lists 0. When non-zero, follows ISO 3166-1 numeric-3 country specifications.
city - Human readable city for the record most of the time, however there are records that are purely numeric and also postal codes
points - Either "null" or a points array to support shape 1. If points is not null, it appears to have 2 possible formats. If it begins with POLYGON, a series of points in lat/lon pairs follows defining a polygon shape follows the keyword POLYGON. If points is not followed by POLYGON keyword, it appears to have another set of coordinates in both Chinese GCJ system and WGS system.