scholarly journals ENSO and interdecadal climate variability over the last century documented by geochemical records of two coral cores from the South West Pacific

2006 ◽  
Vol 6 ◽  
pp. 23-27 ◽  
Author(s):  
T. Ourbak ◽  
T. Corrège ◽  
B. Malaizé ◽  
F. Le Cornec ◽  
K. Charlier ◽  
...  

Abstract. The south west Pacific is affected by climatic phenomena such as ENSO (El Niño Southern Oscillation) or the PDO (Pacific Decadal Oscillation). Near-monthly resolution calibrations of Sr/Ca, U/Ca and δ18Oc were made on corals taken from New Caledonia and Wallis Island. These geochemical variations could be linked to SST (sea surface temperature) and SSS (sea surface salinity) variations over the last two decades, itselves dependent on ENSO occurrences. On the other hand, near-half-yearly resolution over the last century smoothes seasonal and interannual climate signals, but emphasizes low frequency climate variability.

2017 ◽  
Vol 68 (11) ◽  
pp. 2123 ◽  
Author(s):  
I. Beveridge ◽  
T. H. Cribb ◽  
S. C. Cutmore

During a helminthological examination of teleost fish of Moreton Bay (Qld, Australia), 976 fish from 13 orders, 57 families and 133 species were examined and nine species of trypanorhynch metacestodes were identified. Callitetrarhynchus gracilis (Rudolphi, 1819) was the most frequently encountered species, found in 16 species of fish, with Callitetrarhynchus speciosus (Linton, 1897), Pterobothrium pearsoni (Southwell, 1929), Otobothrium alexanderi Palm, 2004, Otobothrium mugilis Hiscock, 1954, Otobothrium parvum Beveridge & Justine, 2007, Proemotobothrium southwelli Beveridge & Campbell, 2001, Pseudotobothrium dipsacum (Linton, 1897) and Heteronybelinia cf. heteromorphi Palm, 1999 occurring in fewer host species and at lower prevalences. Comparisons are made with studies elsewhere in the world and specifically within the South-west Pacific. Of the best studied regions in the South-west Pacific (Heron Island, Lizard Island, New Caledonia and now Moreton Bay), the fauna from Moreton Bay was found to be the most distinctive, with fauna from the three reef locations sharing 35–48% of species between sites and just 12–24% with Moreton Bay. The fauna of trypanorhynch cestodes from Lizard Island and New Caledonia was found to be the most similar.


2021 ◽  
pp. 1
Author(s):  
Yaru Guo ◽  
Yuanlong Li ◽  
Fan Wang ◽  
Yuntao Wei

AbstractNingaloo Niño – the interannually occurring warming episode in the southeast Indian Ocean (SEIO) – has strong signatures in ocean temperature and circulation and exerts profound impacts on regional climate and marine biosystems. Analysis of observational data and eddy-resolving regional ocean model simulations reveals that the Ningaloo Niño/Niña can also induce pronounced variability in ocean salinity, causing large-scale sea surface salinity (SSS) freshening of 0.15–0.20 psu in the SEIO during its warm phase. Model experiments are performed to understand the underlying processes. This SSS freshening is mutually caused by the increased local precipitation (~68%) and enhanced fresh-water transport of the Indonesian Throughflow (ITF; ~28%) during Ningaloo Niño events. The effects of other processes, such as local winds and evaporation, are secondary (~18%). The ITF enhances the southward fresh-water advection near the eastern boundary, which is critical in causing the strong freshening (> 0.20 psu) near the Western Australian coast. Owing to the strong modulation effect of the ITF, SSS near the coast bears a higher correlation with the El Niño-Southern Oscillation (0.57, 0.77, and 0.70 with Niño-3, Niño-4, and Niño-3.4 indices, respectively) than sea surface temperature (-0.27, -0.42, and -0.35) during 1993-2016. Yet, an idealized model experiment with artificial damping for salinity anomaly indicates that ocean salinity has limited impact on ocean near-surface stratification and thus minimal feedback effect on the warming of Ningaloo Niño.


2019 ◽  
Vol 11 (8) ◽  
pp. 919 ◽  
Author(s):  
Ziyao Mu ◽  
Weimin Zhang ◽  
Pinqiang Wang ◽  
Huizan Wang ◽  
Xiaofeng Yang

Ocean salinity has an important impact on marine environment simulations. The Soil Moisture and Ocean Salinity (SMOS) mission is the first satellite in the world to provide large-scale global salinity observations of the oceans. Salinity remote sensing observations in the open ocean have been successfully applied in data assimilations, while SMOS salinity observations contain large errors in the coastal ocean (including the South China Sea (SCS)) and high latitudes and cannot be effectively applied in ocean data assimilations. In this paper, the SMOS salinity observation data are corrected with the Generalized Regression Neural Network (GRNN) in data assimilation preprocessing, which shows that after correction, the bias and root mean square error (RMSE) of the SMOS sea surface salinity (SSS) compared with the Argo observations can be reduced from 0.155 PSU and 0.415 PSU to −0.003 PSU and 0.112 PSU, respectively, in the South China Sea. The effect is equally significant in the northwestern Pacific region. The preprocessed salinity data were applied to an assimilation in a coastal region for the first time. The six groups of assimilation experiments set in the South China Sea showed that the assimilation of corrected SMOS SSS can effectively improve the upper ocean salinity simulation.


1983 ◽  
Vol 31 (6) ◽  
pp. 943 ◽  
Author(s):  
MB Malipatil ◽  
GB Monteith

Austrovelia, gen. nov. (type-species A. queenslandica, sp. nov., from North Queensland), A. caledonica, sp. nov. (from New Caledonia), and Phrynovelia caledonica, sp. nov., and P. bimaculata, sp. nov. (both from New Caledonia) are described and compared with related known genera and species. Altitudinal distribution of A, queenslandica and biogeographic affinities between New Caledonia and the Mount Sorrow tableland in North Queensland are discussed, and a generalized distribution of terrestrial Mesoveliidae in the south-west Pacific is given.


Zootaxa ◽  
2018 ◽  
Vol 4434 (2) ◽  
pp. 201
Author(s):  
GARY M. BARKER

Athoracophoridae are succineoidean terrestrial slugs that constitute a distinctive faunal element of the South West Pacific biogeographic region, with representatives in New Guinea, Australia, New Caledonia, Vanuatu and New Zealand. Despite many studies on morphology, taxonomy and phylogenetic relationships since the first species description in 1832, the understanding of the diversity within the family, as reported in published literature, remains poor with regional disparities in collection and systematic effort, in taxonomic concepts, and in adherence to type concepts. The systematics of Athoracophoridae needs to be re-evaluated through a modern, phylogenetic approach to properly document infra-familial evolution and taxon diversity, advance understanding of evolutionary relationships with other Eupulmonata, and to delineate evolutionary units for conservation prioritization. A catalogue of all class-, family-, genus- and species-group names erected for or used to include Athoracophoridae over the 185 year period 1832 to 2017 is provided, as a first step towards a systematic revision. The following nomenclatural changes are made: lectotype designation for Aneitea macdonaldii Gray, 1860; lectotype designation for Janella papillata Hutton, 1879; type species designation for Amphikonophora Suter, 1897; and lectotype designation for Athoracophorus verrucosus Simroth, 1889. 


2014 ◽  
Vol 11 (6) ◽  
pp. 2971-2978
Author(s):  
I. Astin ◽  
Y. Feng

Abstract. This paper introduces a potential method for the remote sensing of sea surface salinity (SSS) using measured propagation delay of low-frequency Loran-C signals transmitted over an all-seawater path between the Sylt station in Germany and an integrated Loran-C/GPS receiver located in Harwich, UK. The overall delay variations in Loran-C surface waves along the path may be explained by changes in sea surface properties (especially the temperature and salinity), as well as atmospheric dynamics that determine the refractive index of the atmosphere. After removing the atmospheric and sea surface temperature (SST) effects, the residual delay revealed a temporal variation similar to that of SSS data obtained by the European Space Agency's Soil Moisture and Ocean Salinity (SMOS) satellite.


2019 ◽  
Author(s):  
Yue Hu ◽  
Xiaoming Sun ◽  
Hai Cheng ◽  
Hong Yan

Abstract. Tridacna is the largest marine bivalves in the tropical ocean, and its carbonate shell can shed light on high-resolution paleoclimate reconstruction. In this contribution, δ18Oshell was used to estimate the climatic variation in the Xisha Islands of the South China Sea. We first evaluate the sea surface temperature (SST) and sea surface salinity (SSS) influence on modern rehandled monthly (r-monthly) resolution Tridacna gigas δ18Oshell. The obtained results reveal that δ18Oshell seasonal variation is mainly controlled by SST and appear insensitive to local SSS change. Thus, the δ18O of Tridacna shells can be roughly used as a proxy of the local SST: a 1 ‰ δ18Oshell change is roughly equal to 4.41 °C of SST. R-monthly δ18O of a 40-year Tridacna squamosa (3673 ± 28 BP) from the North Reef of Xisha Islands was analyzed and compared with the modern specimen. The difference between the average δ18O of fossil Tridacna shell (δ18O = −1.34 ‰) and modern Tridacna specimen (δ18O = −1.15 ‰) probably implies a warm climate with roughly 0.84°C higher in 3700 years ago. The seasonal variation in 3700 years ago was slightly decreased compared with that suggested by the instrument data, and the switching between warm and cold-seasons was rapid. Higher amplitude in r-monthly and r-annual reconstructed SST anomalies implies an enhanced climate variability in this past warm period. Investigation of the El Ninõ-Southern Oscillation (ENSO) variation (based on the reconstructed SST series) indicates a reduced ENSO frequency but more extreme El Ninõ events in 3700 years ago.


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