The Picarro PI5310 gas concentration analyzer is designed for high-precision measurements of atmospheric nitrous oxide (N2O) and carbon monoxide (CO). Mid-infrared (IR) cavity ring-down spectroscopy (CRDS) produces parts-per-trillion (ppt) precision over a 1 to 1,500 parts-per-billion (ppb) measurement range at less than 5 second intervals. Drift is less than 0.1 ppb, for infrequent analyzer calibration and maintenance. And water (H2O) vapor is measured at parts-per-million (ppm) precision to correct and report N2O and CO concentrations in dry mole fractions. The analyzer has a Linux operating system and can be configured to automatically export measurement data via Ethernet, RS-232 interface, Analog 4-20mA or Modbus outputs. Nitrous oxide is a naturally occurring greenhouse gas that plays a critical role in the nitrogen cycle. Atmospheric concentrations, stable prior to the industrial revolution, have risen dramatically due to agricultural practices and fossil fuel combustion. Precisely measuring atmospheric N2O is important to understanding anthropogenic forces affecting the Earth’s climate.