[AOS25-P01] Spacio-temporal variation of the increasing rate of pCO2 in Kuroshio shelf-slope area
Keywords:coastal region, global warming, pCO2
LTLS: 24C<T<26C and 33.0<S<33.5
LTHS: 24C<T<26C and 34.0<S<34.5
HTLS: 26C<T<28C and 33.0<S<33.5
HTHS: 26C<T<28C and 34.0<S<34.5
Interannual variation of pCO2 within each temperature-salinity domain was then examined. HTLS, and HTHS and LTHS showed positive linear trend of pCO2 with the same increasing rate of +1.9±0.3ppm/y, which value was slightly higher than that observed by Ishii et al. (2014) in the time-series station of 34N, 138E. However, linear trend of pCO2 in LTLS showed significantly higher increasing rate than other three domains, +2.8±0.5ppm/y. Detailed analysis indicated that LTHS and HTHS roughly correspond to the data observed in the offshore side of Kuroshio current in July and August, respectively, while LTLS and HTLS roughly correspond to those observed in the shelf-slope area in July and August, respectively. The observed results indicate that the increasing rate of pCO2 in the Kuroshio shelf-slope area varies even within the summer season, reflecting wide spacio-tenporal variation of water properties caused by complex biogeochemical processes in this quasi-coastal area.