A selection of new science articles from the past week of interest to the SPARC community (a SPARC Office choice).

The response of mesospheric H2O and CO to solar irradiance variability in models and observations. By A. Karagodin-Doyennel et al. in Atmospheric Chemistry and Physics.

Assessing trends in atmospheric circulation patterns across North America. By E.T. Smith et al. in the International Journal of Climatology.

Classification of time series of temperature variations from climatically homogeneous regions based on long‐term persistence. By D. Sarvan et al. in the International Journal of Climatology.

Discussion papers – open for comment:

Anthropogenic Reversal of the Natural Ozone Gradient between Northern and Southern Mid-latitudes. By D.D: Parrish et al. in Atmospheric Chemistry and Physics.

An Arctic Ozone Hole in 2020 If Not For the Montreal Protocol. By C. Wilka et al. in Atmospheric Chemistry and Physics.