Role of advection in Arctic
ecosystems
K.Popova, A.Yool, Y.Aksenov
1D view of ocean ecosystems
Examples
• In May 1999, large numbers of the Pacific diatom
Neodenticula seminae were found in CPR samples in the
Labrador Sea as the first record in the North Atlantic for more
than 800 000 years.
• The event coincided with modifications in Arctic hydrography
and circulation, increased flows of Pacific water into the
Northwest Atlantic and in the previous year the exceptional
occurrence of extensive ice-free water to the North of Canada.
• These observations indicate that N. seminae was carried in a
pulse of Pacific water in 1998/early 1999 via the Canadian
Arctic Archipelago and/or Fram Strait.
• Regional variability was mainly related to the
circulation pattern, but local food availability
was also important.
• A belt of elevated biomass along the Eurasian
continental margin was associated with the
advection of Atlantic pelagic populations
within the Arctic Ocean Boundary Current
along the Siberian shelves and returning
branches along mid-ocean ridges.
What factors control primary production outside of Pacific and Atlantic
inflows?
Subsurface Chl-a maximum
25m
100m
Chl-a
Nutrients
From Carmack and McLaughlin, 2011
• ARIANE
– lagrangian particle tracking
– Forward and backward tracking
• NEMO
– ORCA025 (1/4 degree) global + biology
– Monthly mean fields
• Experiment set up
– Particles placed at 65m in every grid point
– Trajectories are backtracked to 3 points of entry to
the Arctic Ocean
Particles placed at 65m in every
gridpoint
Trajectories are backtracked to 3
points of entry
Colour of the dot shows transient
time from the point of entry (years)
Popova et al., JGR in revision
Colour of the
trajectories
shows depth
(left)
and nitrogen
concentration
(right)
Popova et al., JGR in revision
5
10
15
20 yr
Popova et al., JGR in revision
5
10
15
20 yr
Popova et al., JGR in revision