The Role of the Oceanic Thermal Skin as a Modifier of CO2 Uptake
OCCI Project Funded: 2004
Proposed Research
What are the primary questions you are trying to address
with this research?
This project focuses on the influence of small-scale effects on
the global air-sea flux of CO2. Within the upper millimeter of the
ocean, there is a large temperature gradient, leading to the so-called
oceanic thermal skin effect where the temperature at the ocean surface
is cooler than the water below. This can play a large role in the
air-sea exchange of CO2 through the sensitivity of the solubility
of CO2 to temperature.
What is the significance of this research for others working in this
field of inquiry and for the broader scientific community?
The oceans are the largest absorber of atmospheric CO2. One of the
most urgent requirements in current climate research is the accurate
determination of the global oceanic uptake of CO2. Sources and sinks
of CO2 vary across the globe on a seasonal to annual basis. Knowledge
of the rate of CO2 transfer will allow us to make predictions of
future climate with greater confidence. This project aims to improve
estimates of CO2 uptake by incorporating the skin effect into CO2
flux relationships.
What is the significance of this research for society?
The societal relevance of this project is through an increased understanding
of some of the processes responsible for enhancing oceanic uptake
of CO2, which constitutes the highest percentage of all greenhouse
gases.
When and where will this investigation be conducted??
The compilation of a database with coincident in-situ radiometric
skin temperatures and pCO2 data has been undertaken, and some preliminary
results of this analysis were presented at the Ocean Sciences Meeting
in January 2004. These funds will allow us to complete the analysis
and determine the extent to which the skin effect is responsible
for influencing the estimate of the global CO2 fluxes. This analysis
will be conducted over the coming year, and will culminate with
a paper in a scientific journal.
What are the key tools or instruments needed to conduct
this research?
The data has been acquired, and so the only tool required is a computer
for the data analysis. Matlab will be used extensively for this
project.
What are the greatest challenges – physical or intellectual
– to conducting this investigation?
The greatest challenge in oceanographic research is going to sea
and making measurements. The data for this project has come from
12 measurement campaigns, and provides extensive coverage over the
Northern Hemisphere. Unfortunately, there is scant coverage in the
Southern Oceans (see map show cruise track lines), where there exists
the greatest uncertainties in the oceanic uptake of CO2. One of
the biggest challenges is this research will be to develop a model
that accurately reflects the skin effect on a global basis. However,
it will provide some constraints on the current estimates of the
skin effect.
Is this research part of a larger project or program?
This project is relevant to the International SOLAS (Surface Ocean
Lower Atmosphere Study) initiative which has as its goal to quantify
biogeochemical–physical atmosphere–ocean interactions
and determine how this coupled system affects climate and environmental
change. One of the key objectives is accurate quantification of
air–sea gas transfer rates.
If you have conducted previous/similar work on this subject,
please suggest any web links or citations that might help others
better understand the background to your line of research. If appropriate
and readily available, please suggest or provide photographs, illustrations,
tables, and charts, as well.
Preliminary results for this project were presented at the Ocean
Sciences Meeting, in January 2004. Please see linked schematic 04ward2.pdf.
Below is the map which shows the cruise track lines from which this
data is used. Further information on my research can be found at:
http://www.whoi.edu/science/AOPE/people/bward/
Originally published: January 1, 2004