Synoptic features and structures of some equatorial vortices over the South China Sea in the Malaysian region during the winter monsoon,December 1973

In December 1973, Peninsular Malaysia and Sarawak experienced a few periods of heavy rain caused by westward moving equatorial vortices from the South China Sea. In this report, the synoptic characteristies associated with the development and intersification of these vortices are shown. Structure of one of the disturbances was examined. Disturbances in the trades associated with lateral shear were found to be important for the genesis of the equatorial vortices. However, the intensification of these disturbances depended on the interaction with the cold monsoon surge.     

Response of the mid shoreface of the southern mid-Atlantic Bight to a “northeaster”

An instrumented, bottom-mounted, tripod deployed off Duck, North Carolina, at a depth of 8 m provided time Series of pressure, benthic currents, suspended Sediment concentrations and bed-level changes prior to and during a typical northeast storm. A Strong jet-like southerly-setting current generated by the northeaster was accompanied by downwelling and Strong bottom agitation by wind waves. A total bed-level change of over 15 cm was recorded. After a phase of bed erosion, the bed accreted rapidly. Side-scan imagery supports the inference that offshore or alongshore migration of quasi-discrete sediment lobes may have produced the observed pulse-like accretion.     

The effect of 3,3′,4,4′-tetrachlorobiphenyl and clophen A50 on the hepatic monooxygenase system of Eider Ducklings (Somateria mollissima) with indications for structure-related biotransformation of CB congeners

Environmental contamination may be one cause of the high level of parasitic infections and high death rates of eiders in the Wadden Sea where, among other contaminants, high concentrations of polychlorinated biphenyls (PCBs) occur.To study this problem, four-week-old eider ducklings were exposed to single doses of 3,3′,4,4′-tetrachlorobiphenyl (CB 77; 5 or 50 mg i.p./kg) or Clophen A50 (50 or 200 mg i.p./kg). The control group was injected with corn oil only (5 ml/kg). A dose-dependent induction of the hepatic monooxygenase system was only found in ducklings treated with CB77. Clophen A50 (Clo A50) showed no effect.Comparison of CB patterns in the Clo A50-injected groups with the original mixture revealed differences associated with molecular structure: only CBs with vicinal hydrogen atoms in the meta- and para-positions had     

Watershed‐scale controls on snow accumulation in a small montane watershed,southwestern Alberta,Canada

Snow accumulation in mountain headwater basins is a major water source, particularly in semi‐arid environments such as southern Alberta where water resources are stressed and snowmelt supplies more than 80% of downstream runoff. Relationships between landscape predictor variables and snow water equivalent (SWE) were quantified by combining field and LiDar measurements with classification and regression tree analysis over two winter seasons (2010 and 2011) in a small, montane watershed. 2010 was a below average snow accumulation year, while 2011 was well above normal. In both the field and regression tree data, elevation was the dominant control on snow distribution in both years, although snow distribution was driven by melt processes in 2010 and accumulation processes in 2011. The importance of solar radiation and wind exposure was represented in the regression trees in both years. The regression trees also noted the lower importance of canopy closure, slope, and aspect, which was not observed in the field data. This technique could provide an additional method of forecasting annual water supply from melting snow. However, further research is required to address the lack of data collected above treeline, to provide a full‐basin estimate of SWE. Copyright © 2012 John Wiley & Sons, Ltd.     

Biological and ecological factors related to trace element levels in harbour porpoises (Phocoena phocoena) from European waters

Selected trace elements (Cd, Cu, Hg, Se, Zn) were measured in the kidneys and the liver of 104 harbour porpoises (Phocoena phocoena) stranded along the coasts of France, Galicia (Spain), Ireland, Scotland (UK), and the Netherlands. Generally, relatively low concentrations of toxic elements were encountered in the tissues of European porpoises, except for two individuals, which displayed high hepatic Hg concentrations. Also, elevated Cd levels obtained in Scottish porpoises could be related to their feeding preferences and this result suggests an increase of the proportion of cephalopods in their diet with latitude. Moreover, significant geographical differences were seen in hepatic Zn concentrations; the elevated Zn concentrations displayed by porpoises from the Netherlands may relate their poor health status. Variation in metal concentrations within porpoises from the North Sea is likely to reflect a long-term segregation between animals from northern (Scotland) and southern areas (the Netherlands), making trace elements powerful ecological tracers.     

New Approach to Geochemical Measurement: Estimation of Measurement Uncertainty from Sampling,rather than an Assumption of Representative Sampling

It is argued that the current division between field sampling and chemical analysis is counterproductive in terms of ensuring that geochemical measurement results are fit for their intended purpose. An integrated approach to the whole measurement process has many advantages including no dependence on the two assumptions that either the samples are necessarily representative if taken with a correct protocol, or that the measurement results can be assumed to be true values of chemical concentration. The measurement results then require values of measurement uncertainty, including that from sampling as well as from chemical analysis. This enables the user of the measurement results, rather than the producer, to judge their fitness for a specific purpose. Case studies are used to illustrate the practicality and benefits of this new approach, including the use of measurement results with optimal, but relatively high, levels of uncertainty to make reliable decisions. This contrasts with the traditional assumption that pursuit of the lowest possible measurement uncertainty is the best approach.     

Two-Dimensional Variational Analysis of Near-Surface Moisture from Simulated Radar Refractivity-Related Phase Change Observations

Because they are most sensitive to atmospheric moisture content, radar refractivity observations can provide high-resolution information about the highly variable low-level moisture field. In this study, simulated radar refractivity-related phase-change data were created using a radar simulator from realistic highresolution model simulation data for a dryline case. These data were analyzed using the 2DVAR system developed specifically for the phase-change data. Two sets of experiments with the simulated observations were performed, one assuming a uniform target spacing of 250 m and one assuming nonuniform spacing between 250 m to 4 km. Several sources of observation error were considered, and their impacts were examined. They included errors due to ground target position uncertainty, typical random errors associated with radar measurements, and gross error due to phase wrapping. Without any additional information, the 2DVAR system was incapable of dealing with phase-wrapped data directly. When there was no phase wrapping in the data, the 2DVAR produced excellent analyses, even in the presence of both position uncertainty and random radar measurement errors. When a separate pre-processing step was applied to unwrap the phase-wrapped data, quality moisture analyses were again obtained, although the analyses were smoother due to the reduced effective resolution of the observations by interpolation and smoothing involved in the unwrapping procedure. The unwrapping procedure was effective even when significant differences existed between the analyzed state and the state at a reference time. The results affirm the promise of using radar refractivity phase-change measurements for near-surface moisture analysis.     

Anaerobic oxidation of methane in a cold-water coral carbonate mound from the Gulf of Cadiz

The Gulf of Cadiz is an area of mud volcanism and gas venting through the seafloor. In addition, several cold-water coral carbonate mounds have been discovered at the Pen Duick escarpment amidst the El Arraiche mud volcano field on the Moroccan margin. One of these mounds -named Alpha mound- has been studied to examine the impact of the presence of methane on pore-water geochemistry, potential sulphate reduction (SR) rate and dissolved inorganic carbon (DIC) budget of the mound in comparison with off-mound and off-escarpment locations. Pore-water profiles of sulphate, sulphide, methane, and DIC from the on-mound location showed the presence of a sulphate to methane transition zone at 350 cm below the sea floor. This was well correlated with an increase in SR activity. ¹³C-depleted DIC at the transition zone (−21.9‰ vs. Vienna Pee Dee Belemnite) indicated that microbial methane oxidation significantly contribute to the DIC budget of the mound. The Alpha mound thus represents a new carbonate mound type where the presence and anaerobic oxidation of methane has an important imprint on both geochemistry and DIC isotopic signature and budget of this carbonate mound.