{
  "fields": [{"id":"_id","type":"int"},{"id":"road_id      unique road segment ID","type":"text"}],
  "records": [
    [1,"the_geom     road segment linestring"],
    [2,"osm_id       OSM road ID"],
    [3,"osm_code     OSM code"],
    [4,"osm_fclass   OSM fclass / road-type"],
    [5,"osm_name     OSM road name"],
    [6,"osm_ref      OSM road ref"],
    [7,"osm_oneway   OSM road metadata"],
    [8,"osm_maxspeed OSM road metadata"],
    [9,"osm_layer    OSM road metadata"],
    [10,"osm_bridge   OSM road metadata"],
    [11,"osm_tunnel   OSM road metadata"],
    [12,"NO2points    number of measurements on this road segment"],
    [13,"NO2drives    number of drive passes on this road segment"],
    [14,"NO2_ugm3     NO2 concentration (median of drive pass mean) in µg/m3"],
    [15,"NOpoints     number of measurements on this road segment"],
    [16,"NOdrives     number of drive passes on this road segment"],
    [17,"NO_ugm3      NO concentration (median of drive pass mean) in µg/m3"],
    [18,"CO2points    number of measurements on this road segment"],
    [19,"CO2drives    number of drive passes on this road segment"],
    [20,"CO2_mgm3     CO2 concentration (median of drive pass mean) in mg/m3"],
    [21,"COpoints     number of measurements on this road segment"],
    [22,"COdrives     number of drive passes on this road segment"],
    [23,"CO_mgm3      CO concentration (median of drive pass mean) in mg/m3"],
    [24,"O3points     number of measurements on this road segment"],
    [25,"O3drives     number of drive passes on this road segment"],
    [26,"O3_ugm3      O3 concentration (median of drive pass mean) in µg/m3"],
    [27,"PM25points   number of measurements on this road segment"],
    [28,"PM25drives   number of drive passes on this road segment"],
    [29,"PM25_ugm3    PM2.5 concentration (median of drive pass mean) in µg/m3"]
]}