The Influence of Seafloor Hydrothermal Activity on Major and Trace Elements of the Sediments From the South Mid-Atlantic Ridge

Sediment samples obtained from the South Mid-Atlantic Ridge were analyzed for the major and trace elements by inductively coupled plasma atomic emission spectroscopy and inductively coupled plasma mass spectrometry. Results revealed that the contents of elements(e.g., Fe, Mn, Cu, Zn, V, Co) were high in samples 22V-TVG10 and 26V-TVG05 from the sites near the hydrothermal areas, and low in sample 22V-TVG14, which was collected far from the hydrothermal areas. The contents of Ca, Sr and Ba in the samples showed opposite trends. A positive correlation between the concentrations of metallic elements(Cu, Zn, Co, Ni, Pb, V) and Fe in the samples were observed. These results are consistent with chemical evolution of the dispersing hydrothermal plume.

Imprint of the ENSO on Rainfall and Latent Heating Variability over the Southern South China Sea from TRMM Observations

Analyses of the Tropical Rainfall Measuring Mission(TRMM) datasets revealed a prominent interannual variation in the convective-stratiform rainfall and latent heating over the southern South China Sea(SCS) during the winter monsoon between 1998 and 2010.Although the height of maximum latent heating remained nearly constant at around 7 km in all of the years,the year-to-year changes in the magnitudes of maximum latent heating over the region were noticeable.The interannual variations of the convective-stratiform rainfall and latent heating over the southern SCS were highly anti-correlated with the Ni?o-3 index,with more(less) rainfall and latent heating during La Ni?a(El Ni?o) years.Analysis of the large-scale environment revealed that years of active rainfall and latent heating corresponded to years of large deep convergence and relative humidity at 600 h Pa.The moisture budget diagnosis indicated that the interannual variation of humidity at 600 h Pa was largely modulated by the vertical moisture advection.The year-to-year changes in rainfall over the southern SCS were mainly caused by the interannual variations of the dynamic component associated with anomalous upward motions in the middle troposphere,while the interannual variations of the thermodynamic component associated with changes in surface specific humidity played a minor role.Larger latent heating over the southern SCS during La Ni?a years may possibly further enhance the local Hadley circulation over the SCS in the wintertime.

3-D observations of a red tide event in the offshore water along the western Guangdong coast

From November 24 to 26, 2014, a red tide event occurred in the offshore water off the Hailing Island located at the western Guangdong coast. The red tide appeared as pink strips distributed within 3 km in the offshore water and extended for about 10 km along the shoreline. During the flood tide, the pink seawater rushed to the beach with breaking waves, forming foam strips on the beach. Guangdong Province Key Laboratory for Coastal Ocean Variation and Disaster Prediction Technologies, Guangdong Ocean University, emergently responded to the event and organized three-dimensional observations from the air, onboard and on beach. The preliminary analyses of the cruise data and water samples indicate that the event was induced by non- toxic Noctiluca scintillans, of which the concentration reaches as high as 4 200 cells/L near the surface and 2600 cells/L at the bottom.