cast conducted through sea ice as part of the regular Rothera Time
Series (RaTS) water column profiling.
Biological Time Series (RaTS) started in 1997, operating out of
the British Antarctic
Survey (BAS) research station at Rothera Point on Adelaide Island, at
the West Antarctic Peninsula. RaTS is centred on Ryder Bay, a small
embayment close to Rothera. The ethos of RaTS is to make
high-frequency, sustained observations with which to answer a number of
scientific questions relating to the physical and biological marine
environments, their evolution over time, and their interactions with
the atmosphere and cryosphere. As such, the RaTS
concept is a
development and an extension of our previous nearshore marine ecology
monitoring work undertaken at Signy Island, South Orkneys, from 1989 to
The specific aims
of RaTS are:-
document the seasonal
pattern of sea ice, temperature, salinity, chlorophyll, pH and
macronutrients (N, P, Si) in the water column close to the Antarctic
quantify the extent
of interannual variability and long-term change in physical and
biological oceanography close to the Peninsula, particularly in
relation to large-scale forcing by factors such as
El Niņo and the
Southern Annular Mode.
relate seasonal and
interannual variability in the feeding activity of selected benthic
suspension feeders to variability in the physical environment.
variability in the reproductive biology of selected marine
invertebrates, and relate this where possible to variability in the
Location of Marguerite Bay at
the Western Antarctic Peninsula (left), and location of Ryder Bay close
to Rothera Research Station (right).
RaTS is a major component of BAS' long-term monitoring and survey
initiative, and is coordinated through the BAS Polar Oceans programme.
It has strong links with the Palmer
Long-Term Ecological Research
(Pal-LTER) program, conducted by U.S. colleagues, and is a component of
global oceanographic time series programme.
Since its inception, RaTS has been managed by Andrew Clarke. The
physical oceanography is overseen by Mike Meredith, and the long-term
reproductive output is undertaken by Lloyd Peck in collaboration with
Paul Tyler (National Oceanography Centre, Southampton). Data are held
in a relational database, managed by Helen Peat. Hugh Venables is a
recent addition to the RaTS team, with expertise in physical
oceanography and biogeochemistry. During his time at
BAS, Mark Brandon was a strong contributor to the RaTS programme, and
remains a friend of RaTS at the Open University.
Field data collection is undertaken year-round by marine assistants
wintering at Rothera. Since the start of RaTS, these have been:-