(1) The MMS sounds the atmosphere with a balloon-borne radiosonde , which measures the meteorological parameters of temperature, pressure, relative humidity, wind speed and wind direction.(2) This rate of temperature decrease, the environmental lapse rate, must be measured to be known; this is done routinely by balloons carrying instruments called radiosondes .(3) These problems are sufficiently serious that the US National Weather Service adjusts satellite data every week to match radiosondes, in effect relying upon radiosondes as a reference instrument.(4) They were also used to taking radiosondes into the upper atmosphere to measure temperature, pressure, and humidity.
