The rawinsonde has been the mainstay of moisture measurements since its introduction in the 1930s. Although new observing platforms introduced in the 1990s (such as satellites and ground based GPS systems) provide integrated moisture measurements, none of them provide a detailed vertical moisture profile essential for numerical weather prediction models. The development of a humidity sensor for use on commercial aircraft is an important and exciting prospect for the meteorological community. It has the potential to provide frequent detailed observations of moisture from aircraft that already report temperature and wind measurements on ascent and descent into and out of busy airports.
This paper provides a comparison of an experimental set of humidity observations taken from aircraft outfitted with the new moisture sensor and rawinsonde observations. The results of this comparison should provide benchmark information as to the accuracy of this new instrument.
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