The importance of the Southern Ocean in reducing atmospheric carbon dioxide

Background: The Southern Ocean uptake of CO2 is an important part of the global uptake. Approximately
25% of the CO2 emitted by human-related activities is absorbed annually by the global ocean, which has
mitigated its atmospheric greenhouse effect. Indirect flux estimates suggest large inter-annual variability in the
Southern Ocean (Landschutzer et al., 2015). The controls upon air/sea CO2 flux are not well understood - wind
speed is a major driver but recent data suggest that it cannot explain all of the uncertainty. Direct air/sea CO2
flux measurements are urgently required, but they are technically challenging (Blomquist et al., 2014).
Successful flux measurements have only been collected in recent years.
Hypothesis: Southern Ocean CO2 fluxes demonstrate spatial and temporal variability that cannot be
explained simply by the air/sea CO2 concentration gradient and wind speed.
Approach: The PhD student will measure direct air/sea fluxes of CO2 (and CH4 where possible) using cuttingedge
instrumentation during multiple cruises in the Southern Ocean. They will interpret the data to improve
understanding of the controls upon air/sea CO2 exchange. These data will be used to estimate revised regional
and global CO2 fluxes. They will work closely with world-class researchers participating in an exciting 5 year
Southern Ocean research programme (https://www.bas.ac.uk/project/orchestra/).
Requirements and training: The PhD student will learn the
eddy covariance flux measurement technique, which directly
quantifies CO2 transport to/from the ocean surface by turbulence
(eddies) in the lower atmosphere. They will gain seagoing
experience making measurements in the Southern Ocean
aboard the RRS James Clark Ross.
The PhD student will join an on-going, successful collaborative
team based at PML and University of Exeter. At PML the student
will benefit from working alongside expert researchers measuring
air/sea gas transfer and oceanic CO2 and CH4. At Exeter, they
will benefit from the expertise of world-leading global carbon
cycle researchers.
We seek an enthusiastic, numerate student to help develop a system to make measurements of air/sea CO2
flux in the Southern Ocean. Candidates must be prepared to go to sea for periods of up to 6 weeks to make
measurements in challenging wind and wave conditions. They must have achieved at least a 2:1 BSc Honours
in a physical science (environmental science, chemistry, physics or maths) and be capable of independent and
team work.
Candidates are encouraged to contact the lead supervisor (Tom Bell, [Email Address Removed]) with any scientific
enquiries and for further details/reading.