Comparison of MkIV balloon and ER-2 aircraft measurements of atmospheric trace gases

On May 8, 1997, vertical profiles of over 30 different gases were measured remotely in solar occultation by the Jet Propulsion Laboratory MkIV Interferometer during a balloon flight launched from Fairbanks, Alaska. These gases included H₂O, N₂O, CH₄, CO, NO_x, NO_y, HCl, ClNO₃, CCl₂F₂, CCl₃F, CCl₄, CHClF₂, CClF₂CCl₂F, SF₆, CH₃Cl, and C₂H₆, all of which were also measured in situ by instruments on board the NASA ER-2 aircraft, which was making flights from Fairbanks during this same early May time period as part of the Photochemistry of Ozone Loss in the Arctic Region in Summer (POLARIS) experiment. A comparison of the gas volume mixing ratios in the upper troposphere and lower stratosphere reveals agreement better than 5% for most gases. The three significant exceptions to this are SF₆ and CCl₄ for which the remote measurements exceed the in situ observations by 15-20% at all altitudes, and H₂O for which the remote measurements are up to 30% smaller than the in situ observations near the hygropause.