Long–range transport of the Saharan dust plumes during May–August of each year is a prominent feature over the tropical North Atlantic. Observations of temperature profiles are highly desirable in clarifying the impacts of the Saharan dust plumes over the tropical North Atlantic. In this work we evaluate positive temperature anomalies (inversions in the lower troposphere) in the North Atlantic low troposphere originating from Western Africa, and to examine the correspondence of these events to Saharan dust plumes, using several temperature sources and satellite–detected measurements of Aerosol Index. We combine profiles of temperature observations from FORMOSAT–3/COSMIC (F3C) with aerosol observations from Ozone Monitoring Instrument (OMI) to provide direct evidence of the Saharan dust plumes modifying environmental stability. The F3C observations show good profile measurements compared with the radiosondes in the lower troposphere, with the average temperature differences less than 0.5K. The F3C results were also compared with the Aqua Advanced Infrared Radiation Sounder (AIRS) and meteorological analyses from the National Centers for Environmental Predictions (NCEP), the United Kingdom Met Office (UKMO), and the European Centre for Medium Range Weather Forecast (ECMWF). Our results show that hot air plumes are associated with the Saharan dust plumes during their transport across the tropical North Atlantic. There were eleven distinctive hot air plumes during May–August 2007 and 2008, respectively. These hot air plumes increase environmental temperatures below 5–km altitudes, with the maximum increase of 1–2K around 2–km. This leads to increase of environmental stability below 2–km altitudes and decrease of environmental stability between 2– and 5–km altitudes. By changing the vertical distribution of environmental stability, the Saharan dust plumes act to stabilize environmental air below 2–km while destabilize environmental air from 2– to 5–km altitudes. These results are distinctively presented in the F3C and AIRS observations but less obvious in the meteorological analyses.

Continuous measurement of fine particulate black carbon (BC) was conducted at an urban site of Guangzhou in South China from December 2007 to December 2008. The daily average BC concentrations ranged from 0.6 to 20.5μg m−3, with an average value of 4.7μg m−3, which was substantially higher than those observed in the urban areas of other developed countries. Diurnal fluctuations of BC were marked with two peaks, one in the morning rush hour (08:00LT) and the other in the late evening hour (21:00–22:00LT), while the lowest BC concentrations were observed in the afternoon. Ambient BC concentrations displayed significant seasonal and diurnal variations with higher values in winter and spring, followed by lower concentrations during autumn and summer. Wind speed, wind direction and temperature were important meteorological factors that affected BC concentrations. A clearly negative correlation (r=−0.50, p<0.01) between BC concentrations and wind speed was found during the study period. A specific investigation was conducted to determine the relationship between optical BC and thermal–optical–reflectance elemental carbon (TOR EC) in distinct seasons. Although significant correlations between BC and EC were obtained (r>0.92, p<0.01), the regression slopes (ΔBC/ΔEC) slightly deviated from each other with values of 0.79, 1.18, and 0.81 in winter, spring and summer, respectively, possibly due to the distinct mixing states and source variations in different seasons. The calculated experimental attenuation coefficient showed a higher value (19.3m2g−1) in Guangzhou than the one recommended for typical Aethalometer measurements.

Rapid environmental assessment (REA) involves scoring abundances of ecosystems/species groups and magnitude of pressures, concurrently, using the same logarithmic (0–6) assessment scale. We demonstrate the utility of REA data for an alert system identifying different levels of coastal management concern. Thresholds set for abundances/magnitudes, when crossed, trigger proposed responses. Kerkennah, Tunisia, our case study, has significant natural assets (e.g. exceptional seagrass and invertebrate abundances), subjected to varying levels of disturbance and management concern. Using REA thresholds set, fishing, green algae/eutrophication and oil occurred at ‘low’ levels (scores 0–1): management not (currently) necessary. Construction and wood litter prevailed at ‘moderate’ levels (scores 2–4): management alerted for (further) monitoring. Solid waste densities were ‘high’ (scores 5–6): management alerted for action; quantities of rubbish were substantial (20–200itemsm−1 beach) but not unprecedented. REA is considered a robust methodology and complementary to other rapid assessment techniques, environmental frameworks and indicators of ecosystem condition.

Surface sediments collected along the entire continental shelf of China, including Yellow Sea, the East China Sea (ECS) inner shelf and the South China Sea (SCS), were analyzed for linear alkylbenzenes (LABs), from which regional anthropogenic influences on the marine environment were assessed. The occurrence of LABs (5.6–77ng/g; mean: 25ng/g; median: 20ng/g) implied light sewage contamination in coast sediment off China. Specifically, the SCS had higher sedimentary LAB levels than Yellow Sea and the ECS inner shelf, which was mainly related to the intensity of domestic wastewater discharge and marine fishing activities. Values of L/S and C13/C12 (defined in the main text) suggested certain degradation while I/E indicated limited degradation of LABs. Also, additional input sources and congener inter-conversions may have contributed to the inconsistent results for degradation of LABs in offshore sediments. Atmospheric inputs and wastewater discharge from marine fishing vessels predominantly contributed to sedimentary LABs in Yellow Sea and the SCS, while riverine input was mainly responsible for LABs along the ECS inner shelf.

Atmospheric mercury exits primarily as gaseous mercury and particulate mercury (PHg). Change in the species of atmospheric mercury will pose significant impact on the biogeochemical process of mercury. Here total gaseous mercury (TGM) and total particulate mercury (TPM) were measured from heating season in wintertime to springtime with frequent dust storm during February to May 2009 in the suburban of Hefei, central China, where atmospheric mercury measurements were completely absent. The average concentrations of TGM and TPM were 2.57±1.37ng/m3 and 0.32±0.10ng/m3, respectively. Variations in the TGM were affected by both emissions and meteorological parameters. In the heating period (February), due to coal combustion TGM concentrations were significantly higher than those in the spring (March, April and May). A clear different diurnal variation in TGM concentration was also observed both in late winter and in spring, accompanying with the advance of sunrise. The percentage of total particulate mercury (TPM) in total atmospheric Hg ranged from 5.8%–19.2%, with relatively high levels appeared in March and April. PHg was mainly derived from direct emissions by coal combustion in February and May, while it was dominated by transformation from gaseous Hg on particles in March and April due to dust storms, which may result in more deposition of mercury to ecosystem.

The increase of seawater desalination plants may affect seagrasses as a result of its hypersaline effluents. There are some studies on the salinity tolerance of seagrasses under controlled laboratory conditions, but few have been done in situ. To this end, Cymodocea nodosa shoots were placed during one month at four localities: two close to a brine discharge; and the other two not affected by the discharge, and this experiment was repeated four times. The results obtained showed a decrease in growth and an increased mortality at the localities affected by the brine discharge. An increase was detected in the percentage of horizontal shoots in respect to vertical shoots at the impacted localities. It is probably that not only the average salinity, but also the constant salinity fluctuations and slightly higher temperatures associated with the brine that may have caused physiological stress thus reducing C. nodosa growth and survival.

Mussels (Mytilus galloprovincialis) from the Turkish Straits Systems were analyzed for sixteen parent polycyclic aromatic hydrocarbon (PAH) contents by high performance liquid chromatography (HPLC). This marine organism was selected because of its multitude, wide distribution, being bio indicator for the pollution and consumption by humans. Total PAH concentrations ranged from 1.2 to 589μgg−1 in Istanbul Strait, 0.94–36.4μgg−1 in Marmara Sea and 0.4–47.9μgg−1 in Çanakkale Strait during the samplings. According to the results Istanbul and Çanakkale Straits are more polluted than the Marmara Sea.

We present the first annually resolved record of biologically available Pb and Fe in the Greater North Sea and Iceland during 1040–2004 AD based on shells of the long-lived marine bivalve Arctica islandica. The iron content in pre-industrial shells from the North Sea largely remained below the detection limit. Only since 1830, shell Fe levels rose gradually reflecting the combined effect of increased terrestrial runoff of iron-bearing sediments and eutrophication. Although the lead gasoline peak of the 20th century was well recorded by the shells, bivalves that lived during the medieval heyday of metallurgy showed four-fold higher shell Pb levels than modern specimens. Presumably, pre-industrial bivalves were offered larger proportions of resuspended (Pb-enriched) organics, whereas modern specimens receive fresh increased amounts of (Pb-depleted) phytoplankton. As expected, metal loads in the shells from Iceland were much lower. Our study confirms that bivalve shells provide a powerful tool for retrospective environmental biomonitoring.

Plastic pollution is widespread in the marine environment, and plastic ingestion by seabirds is now widely reported for dozens of species. Beached Northern Fulmars, Great Shearwaters, Sooty Shearwaters and Cory’s Shearwaters are found on Sable Island, Nova Scotia, Canada regularly, and they can be used to assess plastic pollution. All species except Cory’s Shearwaters contained plastic debris in their gastrointestinal tracts. Northern Fulmars, Sooty Shearwaters and Great Shearwaters all showed high prevalence of plastic ingestion (>72%), with Northern Fulmars having the highest number and mass of plastics among the species examined. There was no difference in plastic ingestion between sexes or age classes. In all species user plastics made up the majority of the pieces found, with industrial pellets representing only a small proportion in the samples. Sable Island could be an important monitoring site for plastic pollution in Atlantic Canada.

The level and source of 16 polycyclic aromatic hydrocarbons (PAHs) were investigated in the surface sediments from the Gorgan Bay, Caspian Sea. The sum of 16 PAHs (ΣPAH16) concentrations varied from 107.87 to 516.18ngg−1dry weight, with average value of 270.96±150.47ngg−1dry weight. Ecological risk assessment of PAHs, indicated that adverse biological effects caused by acenaphthene, naphthalene, fluoranthene and Pyrene occasionally and frequently may take place in the sediments of Gorgan Bay. PAHs source identification demonstrated that the PAHs come from mixed and pyrogenic origin.