Table 2.

Details of the ozonesonde dataset used in this study.

Country	Site name	Longitude (°)	Latitude (°)	Elevation (ma.s.l.)	Data source	No. of launch
US (HI)	Hilo	−155.05	19.72	10	NOAA-ESRL	3
US (CA)	Trinidad Head	−124.15	41.06	36	NOAA-ESRL	5
US (CO)	Boulder	−105.20	39.95	1743	NOAA-ESRL	4
US (AL)	Huntsville	−86.65	34.73	203	NOAA-ESRL	5
US (VA)	Wallops Island	−75.47	37.93	13	WOUDC	6
US (RI)	Rhode Island	−71.42	41.49	21	NOAA-ESRL	2
Canada (BC)	Kelowna	−119.4	49.94	456	WOUDC	4
Canada (AB)	Edmonton	−114.1	53.54	766	WOUDC	4
Canada (SK)	Bratt’s Lake	−104.7	50.2	580	WOUDC	4
Canada (NU)	Resolute	−94.97	74.71	46	WOUDC	2
Canada (MB)	Churchill	−94.07	58.74	30	WOUDC	4
Canada (NU)	Eureka	−85.94	79.98	10	WOUDC	3
Canada (ON)	Egbert	−79.78	44.23	252	WOUDC	4
Canada (NS)	Yarmouth	−66.11	43.87	9	WOUDC	3
Canada (NU)	Alert	−62.34	82.49	75	WOUDC	3
Canada (NL)	Goose Bay	−60.36	53.3	36	WOUDC	3
Vietnam	Hanoi	105.8	21.01	7	WOUDC	1
China	Hong Kong	114.17	22.31	66	WOUDC	4
Japan	Naha	127.69	26.21	28	WOUDC	3
Japan	Tateno	140.13	36.06	31	WOUDC	3
Japan	Sapporo	141.33	43.06	26	WOUDC	3
Greenland	Summit	−38.46	72.58	3211	NOAA-ESRL	4
Ireland	Valentia	−10.25	51.93	14	WOUDC	3
Spain	Madrid	−3.58	40.47	631	WOUDC	3
UK	Lerwick	−1.19	60.14	80	WOUDC	5
Belgium	Uccle	4.35	50.8	100	WOUDC	12
Netherlands	De Bilt	5.18	52.1	4	WOUDC	8
Switzerland	Payerne	6.57	46.49	491	WOUDC	12
Germany	Hohenpeissenberg	11.0	47.8	976	WOUDC	18
Norway	Ny-Ålesund	11.95	78.93	11	WOUDC	6
Czech Republic	Prague	14.44	50.0	304	WOUDC	10
Poland	Legionowo	20.97	52.4	96	WOUDC	4
Turkey	Ankara	32.86	39.97	890	WOUDC	2

Note: parentheses after the country name indicate the state or province.