Supplementary information for
Ross Gyre variability modulates oceanic heat supply to-
ward the West Antarctic continental shelf
Channing J. Prend
1
,
2
∗
, Graeme A. MacGilchrist
3
,
4
, Georgy E. Manucharyan
1
, Rachel Q. Pang
3
,
Ruth Moorman
2
, Andrew F. Thompson
2
, Stephen M. Griffies
3
,
5
, Matthew R. Mazloff
6
, Lynne D.
Talley
6
, Sarah T. Gille
6
1
School of Oceanography, University of Washington, Seattle, WA, USA
2
Environmental Science and Engineering, California Institute of Technology, Pasadena, CA, USA
3
Atmospheric and Oceanic Sciences Program, Princeton University, Princeton, NJ, USA
4
School of Earth and Environmental Sciences, University of St Andrews, St Andrews, UK
5
NOAA Geophysical Fluid Dynamics Laboratory, Princeton, NJ, USA
6
Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, USA
∗
Corresponding author
: Channing J. Prend (cprend@uw.edu)
1
Supplementary Figure 1.
(a) 2013-2018 mean ocean surface stress curl, smoothed by a Gaussian
spatial filter with 2
◦
radius. (b) Correlation coefficient between the gyre strength, defined as the
mean value of the barotropic streamfunction within the
−
8 Sverdrup contour, and ocean surface
stress curl in each grid cell. In both panels the green contour marks the mean gyre boundary
and black contours denote sea level pressure. The dashed black box marks the region with high
correlations (i.e. the region that most strongly forces the gyre). The ocean surface stress curl
averaged over this box is presented in Fig. 2a and 6b.
2
Supplementary Figure 2.
(a) Monthly time series of gyre strength (blue) and area (black), defined
as the mean value of the barotropic streamfunction and area enclosed by the
−
8 Sverdrup contour,
respectively. (b) Monthly time series of Amundsen Sea Low central pressure (green), and latitude
(yellow) from reanalysis data
1
.
Supplementary Figure 3.
2018 minus 2014 sea ice concentration (i.e. negative values mean less
sea ice in 2018 compared to 2014). Black contours mark bathymetry in 1000 m intervals and
magenta lines denote the Polar Front (PF) and Southern Boundary of the Antarctic Circumpolar
Current (SBdy)
2
.
3