The NCAR Digital Barometer

Abstract

Atmospheric measurements are being made in rapidly growing numbers as a result of large-scale research program needs and increased operational requirements. Systems are now being deployed that are expected to operate unattended on batteries and to send reliable data for many months. Sensors for these systems must be low in cost and must consume little power. With these guidelines the Research Systems Facility of the National Center for Atmospheric Research has undertaken development of an electronic barometer with signal output particularly suited to digital data systems. Every effort has been made to keep the cost low (approximately $100), the power consumption small (milliwatt range), and the accuracy meteorologically valid for 1 year (±0.1 to ±0.2 kPa). An extensive laboratory testing program has been completed, and we are beginning field experiments that will demonstrate the reliability of the instrument. We discuss here some of the joys and frustrations in new sensor development, as well as the characteristics of the hardware and how those characteristics were determined.