Halogen-based reconstruction of Russian Arctic sea ice area from the Akademii Nauk ice core (Severnaya Zemlya)

The role of sea ice in the Earth climate system is still under debate, although it is known to influence albedo, ocean circulation, and atmosphere-ocean heat and gas exchange. Here we present a reconstruction of 1950 to 1998AD sea ice in the Laptev Sea based on the Akademii Nauk ice core (Severnaya Zemlya, Russian Arctic). The chemistry of halogens bromine (Br) and iodine (I) is strongly active and influenced by sea ice dynamics, in terms of physical, chemical and biological process. Bromine reacts on the sea ice surface in autocatalyzing "bromine explosion" events, causing an enrichment of the Br/Na ratio and hence a bromine excess (Br-exc) in snow compared to that in seawater. Iodine is suggested to be emitted from algal communities growing under sea ice. The results suggest a connection between Br-exc and spring sea ice area, as well as a connection between iodine concentration and summer sea ice area. The correlation coefficients obtained between Br-exc and spring sea ice (r = 0.44) as well as between iodine and summer sea ice (r = 0.50) for the Laptev Sea suggest that these two halogens could become good candidates for extended reconstructions of past sea ice changes in the Arctic

An integrated study of the chemical composition of Antarctic aerosol to investigate natural and anthropogenic sources

During the 2010-11 austral summer, an aerosol sampling campaign was carried out at a coastal Antarctic site (Terra Nova Bay, Victoria Land). In this work, previously published data about water-soluble organic compounds and major and trace elements were merged with novel measurements of major ions, carboxylic acids and persistent organic pollutants (polychlorobiphenyls, polycyclic aromatic hydrocarbons, polychlorinated naphthalenes, polybrominated diphenylethers and organochlorine pesticides) in order to provide a chemical characterisation of Antarctic aerosol and to investigate its sources. The persistent organic pollutants were determined using a high-volume sampler, able to collect both particulate and gaseous fractions, whereas remaining compounds were determined by performing an aerosol size fractionation with a PM10 cascade impactor. Ionic species represented 58% (350 ng m(-3)) of the sum of concentrations of all detected compounds (596 ng m(-3)) in our Antarctic PM10 aerosol samples due to natural emission. Trace concentrations of persistent organic pollutants highlighted that the occurrence of these species can be due to long-range atmospheric transport or due to the research base. Factor analysis was applied to the dataset obtained from the samples collected with the PM10 sampler in order to make a distinction between anthropogenic, crustal and biogenic sources using specific chemical markers

Lake sediment fecal and biomass burning biomarkers provide direct evidence for prehistoric human-lit fires in New Zealand

Deforestation associated with the initial settlement of New Zealand is a dramatic example of how humans can alter landscapes through fire. However, evidence linking early human presence and land-cover change is inferential in most continental sites. We employed a multi-proxy approach to reconstruct anthropogenic land use in New Zealand’s South Island over the last millennium using fecal and plant sterols as indicators of human activity and monosaccharide anhydrides, polycyclic aromatic hydrocarbons, charcoal and pollen as tracers of fire and vegetation change in lake-sediment cores. Our data provide a direct record of local human presence in Lake Kirkpatrick and Lake Diamond watersheds at the time of deforestation and a new and stronger case of human agency linked with forest clearance. The first detection of human presence matches charcoal and biomarker evidence for initial burning at c. AD 1350. Sterols decreased shortly after to values suggesting the sporadic presence of people and then rose to unprecedented levels after the European settlement. Our results confirm that initial human arrival in New Zealand was associated with brief and intense burning activities. Testing our approach in a context of well-established fire history provides a new tool for understanding cause-effect relationships in more complex continental reconstructions

Two thousand years of boreal biomass burning recorded in the NEEM ice cores

New data from Greenland ice cores reveal a major peak in boreal biomass burning during the 1600s AD, presumably related to major regional droughts in Central Asia. This climate-related peak in fire activity is greater even than postindustrial biomass burning

Impact of green on the urban atmosphere in Athens

The increasing concentration of population on limited space,combined with continuing dense build-up and extensive surfacesealing of urban centers characterize the present day situationin the Mediterranean area. The impact on soil, waterbalance, vegetation, air quality and climate generally causefar-reaching changes in the ecosphere. Studies conducted in1981 (CHRONOPOULOU-SERELI, CHRONOPOULOS, HORBERT, KIRCHGEORG1983) have confirmed that because of its highly unfavorablerelief and construction patterns, Athens particularly suffersfrom poor bioclimatic and air quality conditions.In continuing the above-mentioned investigations, still moreresearch programs were carried out in 1984 andin part, 1985.The goal of these measurements, which by now had becomeexpanded to cover the entire Athens area, was to provide asort of bioclimatic overview of conditions there which couldserve as a general basis for recommendations relating to thedevelopment of planning strategies aimed at improving urbanclimatic conditions there. The role of the green areas was tobe given special consideration in this regard.The one-year use of a network of climate measuring stationsand a great number of measuring trips made it possible toarrive at a statistically sound surface distribution ofclimate parameters encompassing the entire Athens urban area

Anforderungsprofile von Umweltmanagern und Umweltoekonomen eine empirische Studie zu Schluesselqualifikationen und fachspezifischen Anforderungen an Hochschulabsolventen mit einem wirtschaftswissenschaftlichen Schwerpunktthema 'Umweltoekonomie und Umweltmanagement'

IAB-92-64.-59 AX 272 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Two thousand years of boreal biomass burning recorded in the Neem ice cores

New data from Greenland ice cores reveal a major peak in boreal biomass burning during the 1600s AD, presumably related to major regional droughts in Central Asia. This climate-related peak in fire activity is greater even than postindustrial biomass burning