Bulletin of the American Meteorological Society "State of the Climate in 2018" report including an overview of the State of the Climate of the Southern Ocean in 2018, included as a sub-section of the Antarctic chapter.

Full publication here

Antarctic chapter here

Citations:

Complete report: 

Blunden, J. and D.S. Arndt, Eds., 2019: State of the Climate in 2018. Bull. Amer. Meteor. Soc., 100(9), Si-S305, doi:10.1175/2019BAMSStateoftheClimate.I.

Antarctic chapter:

Scambos, T. and S. Stammerjohn Eds., 2019: Antarctica and the Southern Ocean [in "State of the Climate in 2018"]. Bull. Amer. Meteor. Soc., 100(9), SI69-S188, doi:10..1175/2019BAMSStateoftheClimate.I.

Southern Ocean section:

Meijers, A., J.-B. Sallee, A. Grey, J. Johnson, K. Arrigo, S. Swart, B. King, M. Meredith, and M. Mazloff, 2019: Southern Ocean [in "State of the Climate in 2018"]. Bull. Amer. Meteor. Soc., 100(9), SI181-S185, doi:10..1175/2019BAMSStateoftheClimate.I.