Response of the near-surface carbonate system of the northwestern Arabian Sea to the southwest monsoon and related biological forcing
Ralf Lendt
Helmuth Thomas
Axel Hupe
V. Ittekkot
Abstract
Underway measurements of the CO 2 partial pressure (pCO 2) and the sea surface temperature were made in the northwestern Arabian Sea during late intermonsoon and southwest (SW) monsoon 1997. Additionally, dissolved inorganic carbon (DIC) and total alkalinity were analyzed from the surface and deeper waters. CO 2 fluxes between atmosphere and ocean surface were estimated. Monsoon-forced changes in the near-surface carbonate system became clearly visible a few weeks after onset of the SW monsoon. Because of the upwelling of CO 2 -rich waters along the Omani coast, DIC and pCO 2 locally increased up to 2210 mmol kg À1 and 715 matm, respectively. The Arabian Sea thus acted as a CO 2 source during SW monsoon. Highest CO 2 fluxes of >150 mmol m À2 d À1 were observed in the upwelling region off Oman, while the open Arabian Sea revealed relatively lower CO 2 fluxes but contributed more to the overall CO 2 release because of its larger area. Total CO 2 emissions from the Arabian Sea from May until August 1997 are estimated to amount 67.6 Tg C. The upwellingÀinduced impacts of biological activity on the carbon cycle were estimated by tracing freshly upwelled water along its transport way along the sea surface. The obtained CO 2 uptake by enhanced net community production (NCP) is $3.6 times higher than the CO 2 emissions. In contrast to phosphate, upwelled nitrate apparently is consumed by NCP within a timescale of some 10 days, and the upwelling thus does not directly supply the central Arabian Sea with nitrate., Response of the near-surface carbonate system of the northwestern Arabian Sea to the southwest monsoon and related biological forcing
Lendt R., Thomas H., Hupe A. and Ittekkot V. (2003) Response of the near-surface carbonate system of the northwestern Arabian Sea to the southwest monsoon and related biological forcing. Journal of Geophysical Research Atmospheres 108(C7): 3222. 10.1029/2000JC000771
@article{Lendt2003,
Title = {Response of the near-surface carbonate system of the northwestern Arabian Sea to the southwest monsoon and related biological forcing},
Author = {Lendt, Ralf and Thomas, Helmuth and Hupe, Axel and Ittekkot, V.},
Editor = {},
Journal = {Journal of Geophysical Research Atmospheres},
Year = {2003},
Pages = {3222},
Volume = {108},
Doi = {10.1029/2000JC000771},
Abstract = {Underway measurements of the CO 2 partial pressure (pCO 2) and the sea surface temperature were made in the northwestern Arabian Sea during late intermonsoon and southwest (SW) monsoon 1997. Additionally, dissolved inorganic carbon (DIC) and total alkalinity were analyzed from the surface and deeper waters. CO 2 fluxes between atmosphere and ocean surface were estimated. Monsoon-forced changes in the near-surface carbonate system became clearly visible a few weeks after onset of the SW monsoon. Because of the upwelling of CO 2 -rich waters along the Omani coast, DIC and pCO 2 locally increased up to 2210 mmol kg À1 and 715 matm, respectively. The Arabian Sea thus acted as a CO 2 source during SW monsoon. Highest CO 2 fluxes of >150 mmol m À2 d À1 were observed in the upwelling region off Oman, while the open Arabian Sea revealed relatively lower CO 2 fluxes but contributed more to the overall CO 2 release because of its larger area. Total CO 2 emissions from the Arabian Sea from May until August 1997 are estimated to amount 67.6 Tg C. The upwellingÀinduced impacts of biological activity on the carbon cycle were estimated by tracing freshly upwelled water along its transport way along the sea surface. The obtained CO 2 uptake by enhanced net community production (NCP) is $3.6 times higher than the CO 2 emissions. In contrast to phosphate, upwelled nitrate apparently is consumed by NCP within a timescale of some 10 days, and the upwelling thus does not directly supply the central Arabian Sea with nitrate., Response of the near-surface carbonate system of the northwestern Arabian Sea to the southwest monsoon and related biological forcing},
}
TY - JOUR
AU - Lendt, Ralf
AU - Thomas, Helmuth
AU - Hupe, Axel
AU - Ittekkot, V.
TI - Response of the near-surface carbonate system of the northwestern Arabian Sea to the southwest monsoon and related biological forcing
T2 - Journal of Geophysical Research Atmospheres
PY - 2003
SP - 3222
VL - 108
DO - 10.1029/2000JC000771
AB - Underway measurements of the CO 2 partial pressure (pCO 2) and the sea surface temperature were made in the northwestern Arabian Sea during late intermonsoon and southwest (SW) monsoon 1997. Additionally, dissolved inorganic carbon (DIC) and total alkalinity were analyzed from the surface and deeper waters. CO 2 fluxes between atmosphere and ocean surface were estimated. Monsoon-forced changes in the near-surface carbonate system became clearly visible a few weeks after onset of the SW monsoon. Because of the upwelling of CO 2 -rich waters along the Omani coast, DIC and pCO 2 locally increased up to 2210 mmol kg À1 and 715 matm, respectively. The Arabian Sea thus acted as a CO 2 source during SW monsoon. Highest CO 2 fluxes of >150 mmol m À2 d À1 were observed in the upwelling region off Oman, while the open Arabian Sea revealed relatively lower CO 2 fluxes but contributed more to the overall CO 2 release because of its larger area. Total CO 2 emissions from the Arabian Sea from May until August 1997 are estimated to amount 67.6 Tg C. The upwellingÀinduced impacts of biological activity on the carbon cycle were estimated by tracing freshly upwelled water along its transport way along the sea surface. The obtained CO 2 uptake by enhanced net community production (NCP) is $3.6 times higher than the CO 2 emissions. In contrast to phosphate, upwelled nitrate apparently is consumed by NCP within a timescale of some 10 days, and the upwelling thus does not directly supply the central Arabian Sea with nitrate., Response of the near-surface carbonate system of the northwestern Arabian Sea to the southwest monsoon and related biological forcing
ER -
Details
Datum01.07.2003
JournalJournal of Geophysical Research Atmospheres