A new high-resolution climatology and volumetric ???,-S census (???????, = 0.1????C, ????S =
0.01) is constructed for the Ross Sea. Property maps (potential temperature, salinity, and
dissolved oxygen) along 40 depth levels and 21 neutral density (????n) surfaces are
A major inflow of Antarctic Surface Water (AASW) is observed branching off
the westward-flowing coastal current near Cape Colbeck. One portion continues
poleward hugging the coast while the other follows the shelf break to the west. The
characteristic ??????V?????? shape of the Antarctic Slope Front over the western Ross Sea is
indicated by a narrow stream of thickened AASW. The entire AASW layer shoals from
east to west.
Two major shoreward inflows of Lower Circumpolar Deep Water (LCDW) are
inferred. A warm and salty tongue from the Balleny Gyre enters the Drygalski and
Joides troughs. A similar tongue is exported from the Ross Gyre and enters the Glomar
Challenger Trough. No significant LCDW inflow is observed over the eastern slope of
the Ross Sea.
The thickest outflows of Shelf Water (SW: ???, ?????? -1.85????C, S > 34.5) and new
Antarctic Bottom Water (AABW: ???, > -1.85????C, ????n > 28.27 kg m-3) are found along the
Drygalski and Joides troughs. Their saltiest (S > 34.7) components are concentrated in
the western Ross Sea, whereas the low-salinity varieties are found throughout the Ross
The most voluminous water mass in the Ross Sea is LCDW. The least abundant
is AABW found primarily over the western slope. Modified CDW (MCDW) in the
western Ross is inferred to be a mixture of 30% AASW and 70% LCDW; whereas
central (eastern) MCDW is 40% (60%) AASW and 60% (40%) LCDW. The same water mass composition is inferred for new AABW in the western and central Ross Sea: 25%
SW and 75% MCDW.
A 40-year freshening trend is detected at different sites along the coastal transit
of AASW from Cape Colbeck to Ross Island. In addition to a freshening, the MCDW
and high-salinity SW also reveal a cooling trend. Conversely, a warming and
salinification is indicated at the main inflows of LCDW.
- Orsi, Alejandro Professor