Investigation and amelioration of long-term instrumental drifts in water vapor and nitrous oxide measurements from the Aura Microwave Limb Sounder (MLS) and their implications for studies of variability and trends

Livesey, Nathaniel J.; Read, William G.; Froidevaux, Lucien; Lambert, Alyn; Santee, Michelle L.; Schwartz, Michael J.; Millán, Luis F.; Jarnot, Robert F.; Wagner, Paul A.; Hurst, Dale F.; Walker, Kaley A.; Sheese, Patrick E.; Nedoluha, Gerald E.

doi:https://doi.org/10.5194/acp-21-15409-2021

Articles | Volume 21, issue 20

https://doi.org/10.5194/acp-21-15409-2021

© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/acp-21-15409-2021

© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 21, issue 20

Research article

|

15 Oct 2021

Research article |

| 15 Oct 2021

Investigation and amelioration of long-term instrumental drifts in water vapor and nitrous oxide measurements from the Aura Microwave Limb Sounder (MLS) and their implications for studies of variability and trends

Nathaniel J. Livesey, William G. Read, Lucien Froidevaux, Alyn Lambert, Michelle L. Santee, Michael J. Schwartz, Luis F. Millán, Robert F. Jarnot, Paul A. Wagner, Dale F. Hurst, Kaley A. Walker, Patrick E. Sheese, and Gerald E. Nedoluha

Data sets

Atmospheric Chemistry Experiment (ACE): Mission overview (http://www.ace.uwaterloo.ca) P. F. Bernath, C. T. McElroy, M. C. Abrams, C. D. Boone, M. Butler, C. Camy-Peyret, M. Carleer, C. Clerbaux, P.-F. Coheur, R. Colin, P. DeCola, M. DeMazière, J. R. Drummond, D. Dufour, W. F. J. Evans, H. Fast, D. Fussen, K. Gilbert, D. E. Jennings, E. J. Llewellyn, R. P. Lowe, E. Mahieu, J. C. McConnell, M. McHugh, S. D. McLeod, R. Michaud, C. Midwinter, R. Nassar, F. Nichitiu, C. Nowlan, C. P. Rinsland, Y. J. Rochon, N. Rowlands, K. Semeniuk, P. Simon, R. Skelton, J. J. Sloan, M.-A. Soucy, K. Strong, P. Tremblay, D. Turnbull, K. A. Walker, I. Walkty, D. A. Wardle, V. Wehrle, R. Zander, and J. Zou https://doi.org/10.1029/2005GL022386

Advancements, measurement uncertainties, and recent comparisons of the NOAA frost point hygrometer (https://gml.noaa.gov/ozwv/wvap/) E. G. Hall, A. F. Jordan, D. F. Hurst, S. J. Oltmans, H. Vömel, B. Kühnreich, and V. Ebert https://doi.org/10.5194/amt-9-4295-2016

EOS MLS Version 4.2x Level 2 data quality and description document (Revision E) (https://disc.gsfc.nasa.gov) N. J. Livesey, W. G. Read, P. A. Wagner, L. Froidevaux, A. Lambert, G. L. Manney, L. F. M. Valle, ,H. C. Pumphrey, M. L. Santee, M. J. Schwartz, S. Wang, R. A. Fuller, R. F. Jarnot, B. W. Knosp, E. Martinez, and R. R. Lay https://mls.jpl.nasa.gov/eos-aura-mls/data-documentation

Ground-based microwave measurements of water vapor from the midstratosphere to the mesosphere (https://www-air.larc.nasa.gov/missions/ndacc/data.html) G. E. Nedoluha, R. M. Gomez, B. C. Hicks, J. Helmboldt, R. M. Bevilacqua, and A. Lambert https://doi.org/10.1029/2010jd014728

Validation of water vapor measured by SABER on the TIMED satellite (http://saber.gats-inc.com/) P. Rong, J. M. Russell, B. T. Marshall, L. L. Gordley, M. G. Mlynczak, and K. A. Walker https://doi.org/10.1016/j.jastp.2019.105099

Data Quality Flags for ACE-FTS Level 2 Version 4.1/4.2 Data Set P. Sheese and K. Walker https://doi.org/10.5683/SP2/BC4ATC

Short summary

The Microwave Limb Sounder (MLS), an instrument on NASA's Aura mission launched in 2004, measures vertical profiles of the temperature and composition of Earth's "middle atmosphere" (the region from ~12 to ~100 km altitude). We describe how, among the 16 trace gases measured by MLS, the measurements of water vapor (H₂O) and nitrous oxide (N₂O) have started to drift since ~2010. The paper also discusses the origins of this drift and work to ameliorate it in a new version of the MLS dataset.