Accidental Oil Spills

Unfortunately, local hydrocarbon pollution incidents have occurred in Antarctica (e.g. Jouventin et al. 1984 Cripps 1992b), and there are many reports of oiled or killed seabirds (e.g. Williams 1984 Croxall 1987). In general, the most significant oil spills have been caused by shipwrecks, collisions or accidents during bunker fuel transfer. Cripps and Shears (1997), for instance, studied the fate of 1,000 l of an accidentally spilled diesel fuel at Faraday Station. Total PAH concentrations in...

Trace Gases

The main atmospheric gases (N2, O2 and Ar) account for more than 99.9 of the total volume. They have limited interaction with incoming solar radiation and do not interact with infrared radiation emitted by the Earth thus, their concentrations are nearly invariant. In contrast, water vapour (with a highly variable volume, but typically in the order of 1 ) and many trace gases, such as CO2, CH4, O3 and N2O, absorb and emit infrared radiation. In spite of their small volume, the so-called...

Global Warming and Climate Variations in Antarctica

1.5.1 Climate Variability and Changes Due to Human Activities The climate varies naturally on all timescales as a consequence of internal (interactions within and between the atmosphere, hydrosphere, biosphere, and cryosphere) and external factors (volcanic eruptions, variations in Earth's orbit, tectonic variations in the position of continents, asteroid impacts). According to Goudie (2002), most of the variability in any climate record on timescales up to a century can often be attributed to...

Antarctic Soils

In the past, some soil scientists were unwilling to identify as soil the weathered surficial deposits in ice-free areas of continental Antarctica. However, as discussed by Bockheim (1982), these materials fit most classical definitions of soils and may support microflora and cryptogams. Since the 1960s, many studies have been published on soils of the Victoria Land cold desert (e.g. Ugolini 1963 Calkin 1964 Claridge 1965 Tedrow and Ugolini 1966 McCraw 1967 Campbell and Claridge 1968 Ugolini...

LlliLiil

1980-'81 1983-84 1988-'90 1990 1994-'95 Fig. 35. Indicative trend (1982-1995) of pesticide concentrations in the Southern Ocean and Antarctica (see text for sources of data and locations) Southwest Pacific sectors of the Southern Ocean, and found a marked decline in total air PCBs from Mauritius to Syowa Station.Year-round sampling at this station revealed higher concentrations in summer than in winter. Throughout 1999, Ockenden et al. (2001) measured PCB concentrations in air from the Falkland...

Natural and Anthropogenic Inputs of Lead to Antarctic Snow

The main natural sources of trace metals in Antarctica are rock and soil dust, sea-salt spray, volcanic emissions and marine biogenic activity. Even in Antarctic snow from the 1970s (Table 2), concentrations of Pb, the most important anthropogenic metal pollutant during this period and the 19th century, were very low and in the same range or lower than those measured in Antarctic ice from the terminal stage of the last ice age (Boutron and Patterson 1987). Thus, natural sources have always made...

Particle Fluxes and the Composition of Surface Sediments

Despite the recent introduction of ultrasensitive analytical techniques, spatiotemporal fluctuations of biological, climatic and environmental factors determine large variations in ocean water-column element concentrations. Sampling and analysis of waters from different sites and depths should therefore be repeated in space and time to reach definite conclusions on the distribution and cycling of trace elements in the sea. This is particularly difficult in the Southern Ocean, which is remote...

Cryptogamic Organisms as Biomonitors of Atmospheric Contaminants

Although lichens and mosses are completely unrelated groups of cryptogamic organisms, they have a number of features in common. They both lack root systems, have a high cation-exchange capacity (CEC), and depend largely on atmospheric deposition for their nutrient supply. Mosses and lichens therefore have elemental compositions which reflect in an integrated way gaseous, dissolved and particulate elements in atmospheric deposition (Bargagli 1998). Owing to their ability to tolerate long periods...

Krill and Pelagic Food Webs

Although the term krill derives from the Norwegian kril, used by whalers to denote small fish, it is now applied to crustaceans eaten by baleen whales in the Southern Ocean, and it is often reserved for the largely dominant species E. superba. This macroplanktonic species plays a central role in the seasonal pack-ice region of the Southern Ocean due to its abundance (probably one of the most abundant and successful animal species on Earth), large size (up to 6 cm long) and fresh weight of about...

Metal Accumulation and Homeostasis in Antarctic Molluscs

The capability of marine molluscs to tolerate and accumulate metals and other persistent contaminants is well known. Since the 1970s, mussels and oysters have been used extensively around the world as bioaccumulators of contaminants for long-term monitoring of coastal marine waters within the context ofMussel Watchprogrammes (e.g. NAS 1980 Lauenstein et al. 1990). A number of papers have been published on metal accumulation in Antarctic molluscs (e.g. Mauri et al. 1990 Berkman and Nigro 1992...

Persistent Organic Pollutants POPs

The discovery and extensive use of organochlorine pesticides such as aldrin, chlordane, DDT, dieldrin, endosulfan, endrin, heptachlor, lindane and toxaphene began during and after World War II. Although chemists were aware that these compounds are very stable, there was little concern about possible long-term environmental effects. In 1962 the book Silent Spring by Rachel Carson raised public concern, drawing a link between the use of organochlorine insecticides and declining bird populations...

Trace Elements in Antarctic Aerosol

Unlike Hg and Se, most trace elements are emitted as fine particles which can be transported in atmospheric air masses over distances ranging from hundreds to several thousand kilometres. Antarctica is thus the best region in which to follow global trends in background concentrations of airborne trace elements. Moreover, as discussed in the previous chapter, atmospheric transport and deposition of Fe, Mn and other trace elements play an important role in the chemistry and productivity of the...

Global Environmental Challenges and the Reduction of Adverse Impacts in Antarctica

The recurring formation of the ozone hole over Antarctica is the best exemplification of the fact that the main environmental problems in the continent are determined by human activity in the rest of the world. The new century will increasingly be characterised by global environmental challenges due to the increasing global population (at present, about a billion people every 11-12 years), the unprecedented exploitation of natural resources and the production of enormous quantities of solid,...