Ocean University of China

About: Ocean University of China is a education organization based out in Qingdao, China. It is known for research contribution in the topics: Population & Sea surface temperature. The organization has 27604 authors who have published 27886 publications receiving 440181 citations. The organization is also known as: Zhōngguó Hǎiyáng Dàxué & OUC.

El Niño modulations over the past seven centuries

Abstract: The El Nino/Southern Oscillation exhibits considerable natural variability on interdecadal to centennial timescales making it difficult to understand how climate change affects it. A reconstruction now shows there has been anomalously high activity in the late twentieth century, relative to the past seven centuries. This is suggestive of a response to global warming, and will provide constraints to improve climate models and projections.

Facile fabrication of acidified g-C3N4/g-C3N4 hybrids with enhanced photocatalysis performance under visible light irradiation

Abstract: A highly efficient visible-light-driven acidified g-C3N4 (ACNS)/g-C3N4 isotype heterojunction photocatalysts were synthesized by ultrasonic dispersion assisted electrostatic self-assembly strategy for the first time. The photocatalytic oxidation ability of the novel photocatalysts were evaluated using methyl orange (MO) as a target pollutant. The obtained ACNS/g-C3N4 photocatalysts were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectrometry (FTIR), UV–vis diffuse reflection spectroscopy (DRS), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) methods. The photocatalysts exhibited a significantly enhanced photocatalytic performance in degrading MO under visible light illumination (λ > 420 nm) compared with the pristine ACNS and g-C3N4 solely. The optimal ACNS content for the photocatalytic activity of the heterostructured composites was determined. The 30 wt.% ACNS/g-C3N4 exhibited the highest photocatalytic activity, which showed a reaction rate constant as high as 0.0216 min−1, 4.3 times higher than that of bare g-C3N4. The mechanism of the photocatalysts was investigated by determination of reactive species in the photocatalytic reactions and photoluminescence technique. The quenching effects of different scavengers displayed that the reactive h+ and O2− played major role in the reaction systems. The synergic effect between the ACNS and g-C3N4 was found to lead to an improved photo-generated carrier separation and hence the photocatalytic activities of the composite photocatalysts were increased significantly.

Increased variability of eastern Pacific El Niño under greenhouse warming

Abstract: The El Nino–Southern Oscillation (ENSO) is the dominant and most consequential climate variation on Earth, and is characterized by warming of equatorial Pacific sea surface temperatures (SSTs) during the El Nino phase and cooling during the La Nina phase. ENSO events tend to have a centre—corresponding to the location of the maximum SST anomaly—in either the central equatorial Pacific (5° S–5° N, 160° E–150° W) or the eastern equatorial Pacific (5° S–5° N, 150°–90° W); these two distinct types of ENSO event are referred to as the CP-ENSO and EP-ENSO regimes, respectively. How the ENSO may change under future greenhouse warming is unknown, owing to a lack of inter-model agreement over the response of SSTs in the eastern equatorial Pacific to such warming. Here we find a robust increase in future EP-ENSO SST variability among CMIP5 climate models that simulate the two distinct ENSO regimes. We show that the EP-ENSO SST anomaly pattern and its centre differ greatly from one model to another, and therefore cannot be well represented by a single SST ‘index’ at the observed centre. However, although the locations of the anomaly centres differ in each model, we find a robust increase in SST variability at each anomaly centre across the majority of models considered. This increase in variability is largely due to greenhouse-warming-induced intensification of upper-ocean stratification in the equatorial Pacific, which enhances ocean–atmosphere coupling. An increase in SST variance implies an increase in the number of ‘strong’ EP-El Nino events (corresponding to large SST anomalies) and associated extreme weather events. Despite inter-model differences in predicting the details of the eastern Pacific El Nino, a robust increase in the corresponding sea surface temperature variability under greenhouse warming is found across models.