|
Titel |
Dynamics of air–sea CO2 fluxes in the northwestern European shelf based on voluntary observing ship and satellite observations |
VerfasserIn |
P. Marrec, T. Cariou, E. Macé, P. Morin, L. A. Salt, M. Vernet, B. Taylor, K. Paxman, Y. Bozec |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1726-4170
|
Digitales Dokument |
URL |
Erschienen |
In: Biogeosciences ; 12, no. 18 ; Nr. 12, no. 18 (2015-09-18), S.5371-5391 |
Datensatznummer |
250118095
|
Publikation (Nr.) |
copernicus.org/bg-12-5371-2015.pdf |
|
|
|
Zusammenfassung |
From January 2011 to December 2013, we constructed a comprehensive pCO2
data set based on voluntary observing ship (VOS) measurements in the western
English Channel (WEC). We subsequently estimated surface pCO2 and
air–sea CO2 fluxes in northwestern European continental shelf waters
using multiple linear regressions (MLRs) from remotely sensed sea surface
temperature (SST), chlorophyll a concentration (Chl a), wind speed (WND),
photosynthetically active radiation (PAR) and modeled mixed layer depth
(MLD). We developed specific MLRs for the seasonally stratified northern WEC
(nWEC) and the permanently well-mixed southern WEC (sWEC) and calculated
surface pCO2 with uncertainties of 17 and 16 μatm,
respectively. We extrapolated the relationships obtained for the WEC based
on the 2011–2013 data set (1) temporally over a decade and (2) spatially in the
adjacent Celtic and Irish seas (CS and IS), two regions which exhibit
hydrographical and biogeochemical characteristics similar to those of WEC
waters. We validated these extrapolations with pCO2 data from the SOCAT
and LDEO databases and obtained good agreement between modeled and observed
data. On an annual scale, seasonally stratified systems acted as a sink of
CO2 from the atmosphere of −0.6 ± 0.3, −0.9 ± 0.3 and −0.5 ± 0.3 mol C m−2 yr−1 in the northern Celtic Sea, southern Celtic sea and nWEC,
respectively, whereas permanently well-mixed systems acted as source of
CO2 to the atmosphere of 0.2 ± 0.2 and 0.3 ± 0.2 mol C m−2 yr−1 in the sWEC and IS, respectively. Air–sea CO2
fluxes showed important inter-annual variability resulting in significant
differences in the intensity and/or direction of annual fluxes. We scaled
the mean annual fluxes over these provinces for the last decade and obtained
the first annual average uptake of −1.11 ± 0.32 Tg C yr−1 for
this part of the northwestern European continental shelf. Our study showed
that combining VOS data with satellite observations can be a powerful tool
to estimate and extrapolate air–sea CO2 fluxes in sparsely sampled
area. |
|
|
Teil von |
|
|
|
|
|
|