A Quantum Cascade laser spectrometer for measurement of water vapor isotopes in the urban environment

A 7.12 μm Quantum Cascade laser-based water vapor isotope spectrometer for the real time measurement of H 2 O 16 , H 2 O 18 and δ 18 O in the urban environment was developed with a detection limit for δ 18 O of 0.42 ‰.