Improved water vapour spectroscopy in the 4174-4300 cm-1 region and its impact on SCIAMACHY HDO/H2O measurements

The relative abundance of the heavy water isotopologue HDO provides a deeper insight into the atmospheric hydrological cycle. The SCanning Imaging Absorption spectroMeter for Atmospheric CartograpHY (SCIAMACHY) allows for global retrievals of the ratio HDO/H2O in the 2.3 micron wavelength range. However, the spectroscopy of water lines in this region remains a large source of uncertainty for these retrievals. We therefore evaluate and improve the water spectroscopy in the range 4174–4300 cm−1 and test if this reduces systematic uncertainties in the SCIAMACHY retrievals of HDO/H2O. We use a laboratory spectrum of water vapour to fit line intensity, air broadening and wavelength shift parameters. The improved spectroscopy is tested on a series of ground-based high resolution FTS spectra as well as on SCIAMACHY retrievals of H2O and the ratio HDO/H2O. We find that the improved spectroscopy leads to lower residuals in the FTS spectra compared to HITRAN 2008 and Jenouvrier et al. (2007) spectroscopy, and the retrievals become more robust against changes in the retrieval window. For both the FTS and SCIAMACHY measurements, the retrieved total H2O columns decrease by 2–4% and we find a negative shift of the HDO/H2O ratio, which for SCIAMACHY is partly compensated by changes in the retrieval setup and calibration software. The updated SCIAMACHY HDO/H2O product shows somewhat steeper latitudinal and temporal gradients and a steeper Rayleigh distillation curve, strengthening previous conclusions that current isotope-enabled general circulation models underestimate the variability in the near-surface HDO/H2O ratio.

Material culture entanglements of early wetland sites in central Switzerland (4300-3850 BC)

In central Switzerland, the earliest wetland settlements with definitely attested finds and features date into the second half of the 5th millennium BC. Combining the information they have yielded with that from dryland sites, we can construct a detailed picture of material culture at the turn of the 5th to the 4th millennium. On this basis, the definition of clearly delimited archaeological cultures seems questionable, not only from a theoretical point of view. Similiarities and differences in the pottery show small-scale regional units defined via vessel forms as well as stylistic and technological aspects. Yet there are also inter-regional connections: roundbased vessels with opposing handles are typical for Lake Zurich, central and western Switzerland, the Valais and the central Rhône valley. In turn, ‘foreign‘ types such as shoulder-band beakers indicate regular connections between groups living in central Switzerland and those in Alsace and southern Germany. Are these beakers ‘imports‘ or locally produced items (‘imitations‘) indicating the adoption of ‘foreign‘ vessel types and concepts? This and similar material culture phenomena result in a picture of many material entanglements and problematise the kinds of relationships and mobility which might have existed. Our paper addresses these questions and discusses how and whether these interwoven connections changed in the early 4th millennium.

A parent-completed respiratory questionnaire for 1-year-old children: repeatability

BACKGROUND AND AIMS: There are few standardised questionnaires for the assessment of respiratory symptoms in preschool children. We have developed and tested the short-term repeatability of a postal questionnaire on respiratory symptoms for 1-year-old children. METHODS: A newly developed postal questionnaire for the assessment of wheeze and other respiratory symptoms was sent to parents of a population-based random sample of 4300 children aged 12-24 months. After an interval of 3 months, a random sample of 800 respondents received the questionnaire a second time. The responses were compared using Cohen's kappa (kappa) to assess agreement corrected for chance. RESULTS: The first questionnaire was returned by 3194 (74%) families, the second one by 460/800 (58%). Repeatability was excellent (kappa 0.80-0.96) for questions on household characteristics, environmental exposures and family history, good (kappa 0.61-0.80) for questions on prevalence, severity and treatment of wheeze, and moderate (kappa 0.39-0.66) for chronic cough and upper respiratory symptoms. CONCLUSIONS: This short postal questionnaire designed for use in population-based studies has excellent repeatability for family and household characteristics and good repeatability for questions on wheeze. Short-term changes in symptom status might be responsible for variable answers on recent chronic cough and upper respiratory symptoms. Overall, the questionnaire is a valuable instrument for community-based research on respiratory symptoms in 1 to 2-year-old children.

14 000 Jahre Klimageschichte am Lauenensee

Anhand fossiler Überreste von Chironomiden (Zuckmücken) in den Sedimenten des Lauenensees wurden Temperaturveränderungen im westlichen Berner Oberland über die letzten 14 000 Jahre rekonstruiert. Mittlere Juli-Lufttemperaturen wurden mithilfe eines Kalibrationsdatensatzes und eines Temperaturrekonstruktionsmodells rekonstruiert, welches bereits in einer früheren Studie entwickelt worden ist. Während dem Allerød (~14,000-12,700 kal. Jahre vor heute) wurden Temperaturen zwischen 8,7-12,0 °C berechnet, während der Jüngeren Dryaszeit (-12 700- 11 700 kal. Jahre vor heute) Werte um 10,2-10,7 °C und während dem Früh- bis Mittelholozän (-11 700-3000 kal. Jahre vor heute) Temperaturen um 12,0-14,5 °C. Für das Spätholozän (ab -3000 kal. Jahre vor heute) wurden tiefere Temperaturen (10-12 °C) geschätzt. Der menschliche Einfluss wird ab 4300 kal. Jahre vor heute deutlich in den Chironomidenvergesellschaftungen sichtbar und beeinträchtigt möglicherweise die Verlässlichkeit der Temperaturrekonstruktion für dieses Zeitintervall. Die Temperaturrekonstruktion stimmt gut mit anderen paläoklimatischen Rekonstruktionen der Alpen sowie dem Anstieg der Baumgrenze in dieser Region überein.

Pile-dwellings of the Neolithic and the Bronze Age in Switzerland. Long-term research and future tasks

Swiss lake-side settlements dating between 4300 and 800 BC were first recognized in the early 19th century and between 1854 and 1880 early research boomed due to the first scientific studies and the artificial lowering of lakes in Western Switzerland. In the 20th century underwater and wetland archaeology experienced an enormous surge not only because of large rescue excavations, due to extensive motorway construction projects but also due to the evolution of modern IT technology in the 1970s. For the first time huge quantities of ancient wooden structures could be dated by dendrochronology. This produced a quantum leap in the 150 years of pile-dwelling research. In 2011, the UNESCO World Heritage Committee recognized the outstanding universal value of these sites. This article presents an overview about Swiss pile-dwellings of the Neolithic and the Bronze Age and the results of two recent diploma works (case study Sutz-Lattrigen Haupstation innen and case study Seedorf Lobsigensee) as examples of research and cooperation between universities and government agencies for cultural heritage management.

Signal Processing for the Measurement of the Deuterium/Hydrogen Ratio in the Local Interstellar Medium

We report on a comprehensive signal processing procedure for very low signal levels for the measurement of neutral deuterium in the local interstellar medium from a spacecraft in Earth orbit. The deuterium measurements were performed with the IBEX-Lo camera on NASA’s Interstellar Boundary Explorer (IBEX) satellite. Our analysis technique for these data consists of creating a mass relation in three-dimensional time of flight space to accurately determine the position of the predicted D events, to precisely model the tail of the H events in the region where the H tail events are near the expected D events, and then to separate the H tail from the observations to extract the very faint D signal. This interstellar D signal, which is expected to be a few counts per year, is extracted from a strong terrestrial background signal, consisting of sputter products from the sensor’s conversion surface. As reference we accurately measure the terrestrial D/H ratio in these sputtered products and then discriminate this terrestrial background source. During the three years of the mission time when the deuterium signal was visible to IBEX, the observation geometry and orbit allowed for a total observation time of 115.3 days. Because of the spinning of the spacecraft and the stepping through eight energy channels the actual observing time of the interstellar wind was only 1.44 days. With the optimised data analysis we found three counts that could be attributed to interstellar deuterium. These results update our earlier work.

Paleolimnological evidence for increased landslide activity due to forest clearing and land-use since 3600 cal BP in the western Swiss Alps

Schwarzsee is located in the western Swiss Alps, in a region that has been affected by numerous landslides during the Holocene, as evidenced by geological surveys. Lacustrine sediments were cored to a depth of 13 m. The vegetation history of the lake's catchment was reconstructed and investigated to identify possible impacts on slope stability. The pollen analyses record development of forest cover during the middle and late Holocene, and provide strong evidence for regional anthropogenic influence such as forest clearing and agricultural activity. Vegetation change is characterized by continuous landscape denudation that begins at ca. 4300 cal. yrs BP, with five distinct pulses of increased deforestation, at 3650, 2700, 1500, 900, and 450 cal. yrs BP. Each pulse can be attributed to increased human impact, recorded by the appearance or increase of specific anthropogenic indicator plant taxa. These periods of intensified deforestation also appear to be correlated with increased landslide activity in the lake's catchment and increased turbidite frequency in the sediment record. Therefore, this study gives new evidence for a strong influence of vegetation changes on slope stability during the middle and late Holocene in the western Swiss Alps, and may be used as a case study for anthropogenically induced landslide activity.

Aus schmelzendem Eis. Funde vom Schnidejoch.

Am Ende des Hitzesommers 2003 entdeckten Wanderer am Rande eines kleinen Eisfeldes erstmals prähistorische Objekte. Die Fundstelle liegt am Schnidejoch, einem alpinen Übergang, der das Simmental mit dem Rhônetal verbindet. Bis heute liegen von dieser außergewöhnlichen Fundstelle rund 900 Funde vom Neolithikum bis zum Mittelalter vor. Die Forschungen am Schnidejoch können auch als „Archäologie zwischen Gletschern und Gipfeln“ bezeichnet werden. Die Fundstelle befindet sich auf 2750 m Höhe und wird von der höchsten Erhebung der westlichen Berner Alpen, dem 3248 m hohen Wildhorn, überragt. Die ältesten Objekte werden in die Zeitspanne von 4800 bis 4300 v. Chr. datiert. Es handelt sich um Fragmente von Pfeilen und um eine Schale aus Ulmenholz. Weitere Leder- und Pfeilfragmente zeigen, dass der Pass auch in der zweiten Hälfte des 4. Jahrtausends v. Chr. benutzt wurde. Eine ganze Serie von Objekten stammt aus dem Zeitraum um 2800 v. Chr.: eine komplette Bogenausrüstung, bestehend aus Pfeilbogen, Bogensehne, Bogenfutteral, Pfeilschäften und Pfeilspitzen. Ebenfalls zu diesem Ensemble gehören Bekleidungsreste: Teile eines Grasumhangs, Schuhfragmente und ein Hosenbein aus Leder. Es ist wenig wahrscheinlich, dass die in den Bergen lebensnotwendige Bekleidung und die Bewaffnung einfach verloren wurden. Es ist deshalb zu vermuten, dass am Schnidejoch vor fast 5000 Jahren jemand zu Tode kam; eine Leiche wurde aber – anders als beim „Ötzi“ – nicht gefunden. Möglicherweise wurde die am Schnidejoch umgekommene Person geborgen und in einem zeitgleich errichteten Kollektivgrab im Tal bestattet.

Die Bucht von Sutz-Lattrigen. Vom Neolithikum bis in die Bronzezeit

Im westlichen Landesteil der Schweiz bilden Bieler­, Murten­ und Neuenburgersee eine archäologische Landschaft von besonderer Bedeutung. Hier wurden 200 der über 450 Pfahlbaufundstellen des schweizerischen Mittellandes entdeckt. Die erste Kartierung von unter Wasser liegenden Strukturen am Bielersee erfolgte 1811; 1854 wurden zum ersten Mal Funde publiziert und 1928 eine umfassende Darstellung aller Siedlungsplätze veröffentlicht. Danach verfiel die regionale Archäologie in einen Dornröschenschlaf, der erst in den 1970er­Jahren endete: Der Autobahnbau am Jurasüdfuss führte zu den ersten modernen Ausgrabungen und zur Herausbildung einer professionellen Denkmal­ pflege. Aus der zweiten Bestandsaufnahme des Bielersees entwickelte sich in den frühen 1980er­Jahren ein umfassendes Programm zur Dokumentation bedrohter neolithischer und bronzezeitlicher Siedlungsreste. Seit 1988 werden in der Gemeinde Sutz­Lattrigen Rettungsgrabungen und Schutzmaßnahmen durchgeführt, weil die am Seegrund liegenden archäologischen Fundschichten und Strukturen von Erosi­ on bedroht sind. Bisher wurden am 3 km langen Uferabschnitt über 40 000 m2 Seegrund untersucht. Damit sollen die zahlreichen Reste von Siedlungen aus dem Zeitraum zwischen 4300 und 1600 v. Chr. dokumentiert und vor weiterem Zerfall bewahrt werden.