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

Sudden Stratospheric Warmings. By M.P. Baldwin et al. in the Reviews of Geophysics.

Strong day-to-day variability of the Asian Tropopause Aerosol Layer (ATAL) in August 2016 at the Himalayan foothills. By S. Hanumanthu et al. in Atmospheric Chemistry and Physics.

Tropical temperature variability in the UTLS: New insights from GPS radio occultation observations. By B. Scherllin-Pirscher et al. in the Journal of the Climate.

Clouds, radiation, and atmospheric circulation in the present‐day climate and under climate change. By A. Voigt et al. in WIREs Climate Change.

Discussion papers – open for comment:

Reanalysis intercomparison of potential vorticity and potential-vorticity-based diagnostics. By L.F. Millan, G.L. Manney, and Z.D. Lawrence in Atmospheric Chemistry and Physics.

The Impact of Volcanic Eruptions of Different Magnitude on Stratospheric Water Vapour in the Tropics. By C.A. Kroll et al. in Atmospheric Chemistry and Physics.

Smoke-charged vortices in the stratosphere generated by wildfires and their behaviour in both hemispheres: comparing Australia 2020 to Canada 2017. By H. Lestrelin et al. in Atmospheric Chemistry and Physics.