Extended Data Table 1 Water mass definitions

From: Southern Ocean freshening stalls deep ocean CO2 release in a changing climate

Section

Date

Winter Water

Upper Circumpolar Deep Water

Temperature

Salinity

Temperature

Salinity

S04I

January 2013

T < -1.5

 

T > 1.5

S > 34.5

P16S

April 2014

T < -1.3

S > 34

 

S > 34.68

A12

December 2014

T < -1.5

 

T > 0.7

S > 34.68

I08S

February 2016

T < -1

  

S > 34.6

P18

Dec 2016 / Jan 2017

T < -1.3

  

S > 34.65

S04P

March 2018

T < -1.5

S > 33.9

T > 1.5

S > 34.5

I06S

April/May 2019

T < -1.3

  

S > 34.65

  1. Water mass definitions based on temperature and salinity criteria for each section. In sections where salinity (temperature) thresholds are not listed, temperature (salinity) alone provided sufficient contrast for identification of the water masses.