NWS weather balloons alone are about 100 balloons over China: https://www.weather.gov/jetstream/radiosondes https://www.weather.gov/jetstream/radiosondes Tons

NWS weather balloons alone are about 100 balloons over China: https://www.weather.gov/jetstream/radiosondes https://www.weather.gov/jetstream/radiosondes Tons more in amateur radio etc., see APRS