|
|
|
|
|
| Alvarez, M.; Tanhua, T.; Brix, H.; Lo Monaco, C.; Metzl, N.; Mcdonagh, E. L.; Bryden, H. L.. |
| Within the Subantarctic Mode Water (SAMW) density level, we study temporal changes in salinity, nutrients, oxygen and TTD (Transit Time Distribution) ages in the western (W) and eastern (E) subtropical gyre of the Indian Ocean (IO) from 1987 to 2002. Additionally, changes in Total Alkalinity (TA) and Dissolved Inorganic Carbon (DIC) are evaluated between 1995 and 2002. The mechanisms behind the detected changes are discussed along with the results from a hindcast model run (Community Climate System Model). The increasing salinity and decreasing oxygen trends from 1960 to 1987 reversed from 1987 to 2002 along the gyre. In the W-IO a decreasing trend in TTD ages points to a faster delivery of SAMW, thus less biogenic matter remineralization, explaining the... |
| Tipo: Text |
Palavras-chave: Indian Ocean; Subantarctic Mode Water; Biogeochemistry. |
| Ano: 2011 |
URL: https://archimer.ifremer.fr/doc/00253/36400/34942.pdf |
| |
|
|
| Garry, F. K.; Mcdonagh, E. L.; Blaker, A. T.; Roberts, C. D.; Desbruyères, Damien; Frajka-williams, E.; King, B. A.. |
| We construct a novel framework to investigate the uncertainties and biases associated with estimates of deep ocean temperature change from hydrographic sections, and demonstrate this framework in an eddy‐permitting ocean model. Biases in estimates from observations arise due to sparse spatial coverage (few sections in a basin), low frequency of occupations (typically 5‐10 years apart), mismatches between the time period of interest and span of occupations, and from seasonal biases relating to the practicalities of sampling during certain times of year. Between the years 1990 and 2010, the modeled global abyssal ocean biases are small, although regionally some biases (expressed as a heat flux into the 4000 ‐ 6000 m layer) can be up to 0.05 W m−2. In this... |
| Tipo: Text |
Palavras-chave: Deep oceans; Temperature trends; Ocean heat content; Decadal variability; Ocean modeling; Observational uncertainties. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00479/59021/61642.pdf |
| |
|
|
| Desbruyères, Damien; Sinha, B.; Mcdonagh, E. L.; Josey, S. A.; Holliday, N. P.; Smeed, D. A.; New, A. L.; Megann, A.; Moat, B. I.. |
| The decadal to multi‐decadal temperature variability of the intermediate (700 – 2000 m) North Atlantic Subpolar Gyre (SPG) significantly imprints the global pattern of ocean heat uptake. Here, the origins and dominant pathways of this variability are investigated with an ocean analysis product (EN4), an ocean state estimate (ECCOv4), and idealized modeling approaches. Sustained increases and decreases of intermediate temperature in the SPG correlate with long‐lasting warm and cold states of the upper ocean with the largest anomalous vertical heat exchanges confined to the vicinity of continental boundaries and strong ocean currents. In particular, vertical diffusive processes along the boundaries of the Labrador, Irminger, and Newfoundland basins are... |
| Tipo: Text |
|
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00636/74853/75239.pdf |
| |
|
|
| Desbruyeres, D.g.; Mcdonagh, E. L.; King, B. A.; Garry, F. K.; Blaker, A. T.; Moat, B. I.; Mercier, Herle. |
| The vertical structure of temperature trends in the northeastern Atlantic (NEA) is investigated using a blend of Argo and hydrography data. The representativeness of sparse hydrography sampling in the basin mean is assessed using a numerical model. Between 2003 and 2013, the NEA underwent a strong surface cooling (0–450 m) and a significant warming at intermediate and deep levels (1000 m to 3000 m) that followed a strong cooling trend observed between 1988 and 2003. During 2003–2013, gyre-specific changes are found in the upper 1000 m (warming and cooling of the subtropical and subpolar gyres, respectively), while the intermediate and deep warming primarily occurred in the subpolar gyre, with important contributions from isopycnal heave and water mass... |
| Tipo: Text |
Palavras-chave: North Atlantic; Temperature; Observations; Hiatus. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00236/34677/33026.pdf |
| |
|
|
|
