MONTHLY ISOTOPIC SIGNAL OF THE PRECIPITATED WATER IN THE PROVINCE OF TRENTO: LAGRANGIAN ANALYSIS AND DISCUSSION OF MEASUREMENTS

The present work has been performed in the framework of the research project AQUAPAST. The main focus of AQUAPAST is the reconstruction of past climate changes in the atmospheric circulation and in particular in the water vapour transport mechanism over the Mediterranean area starting from the analysis of the isotopic content of cave speleothemes in the Trentino Province (North-East of Italy). A Lagrangian methodology for the reconstruction and the analysis of the airstreams which govern the transport of water vapour has been applied to recent events. The average monthly isotopic signal of the precipitation water sampled in stations located in key geographic settings in the Province of Trento is used as tracer to infer the origin of the precipitating water and to validate the Lagrangian analysis. A comparison between the isotopic signal of November 2002 and November 2003 is here presented, as most of the yearly precipitation falls in November over the Eastern Alps. Hypotheses are proposed about the meteorological factors (e.g. monthly averaged sea surface temperature, atmospheric circulation, etc.) determining different isotopic signals in the two years

What is a smart device? - a conceptualisation within the paradigm of the internet of things

The Internet of Things (IoT) is an interconnected network of objects which range from simple sensors to smartphones and tablets; it is a relatively novel paradigm that has been rapidly gaining ground in the scenario of modern wireless telecommunications with an expected growth of 25 to 50 billion of connected devices for 2020 Due to the recent rise of this paradigm, authors across the literature use inconsistent terms to address the devices present in the IoT, such as mobile device, smart device, mobile technologies or mobile smart device. Based on the existing literature, this paper chooses the term smart device as a starting point towards the development of an appropriate definition for the devices present in the IoT. This investigation aims at exploring the concept and main features of smart devices as well as their role in the IoT. This paper follows a systematic approach for reviewing compendium of literature to explore the current research in this field. It has been identified smart devices as the primary objects interconnected in the network of IoT, having an essential role in this paradigm. The developed concept for defining smart device is based on three main features, namely context-awareness, autonomy and device connectivity. Other features such as mobility and userinteraction were highly mentioned in the literature, but were not considered because of the nature of the IoT as a network mainly oriented to device-to-device connectivity whether they are mobile or not and whether they interact with people or not. What emerges from this paper is a concept which can be used to homogenise the terminology used on further research in the Field of digitalisation and smart technologies

Atmospheric forcing of sulphate in speleothem carbonate.

Sulphur emitted into the atmosphere from anthropogenic combustion of fossil fuels has played a dramatic role in moderating climatic change. Trace amounts of sulphur in calcite speleothems suggest that stalagmites may act as archives of sulphur deposition, thereby recording aspects of atmospheric variability in sulphur content in mid-latitude locations. Stalagmites obtained from a variety of sites with proportions of sulphur from different sources display concentrations ranging from 15 to 200 ppb and trends in sulphur which either remain constant or show an increase over the past 150 years. Due to the clear isotopic distinction between marine (+21‰), geological (+10‰ to +30‰), atmospheric pollution (0–4‰) and volcanic sources of sulphur (0–5‰), isotopic ratios provide a diagnostic tool with which changes in the source of atmospheric sulphur can be detected in a more reliable fashion than concentration alone. Initial results comparing δ34S profiles from stalagmites in both coastal and pollution dominated locations have yielded isotope data identifying secular trends and accurately reflecting marine and anthropogenic sources of sulphur, respectively. At Grotta di Ernesto cave, near the Dolomites in northern Italy, a rise in sulphur concentration from 15 to 65 ppm in speleothem calcite is thought to reflect increasing anthropogenic pollution. δ34S ratios are now being used to assess this assertion and determine how sulphur atmospheric inputs may be buffered by processes of storage, release and transformation within the overlying ecosystem prior to incorporation into speleothem calcite. Initial results show a clear isotopic distinction between host bedrock (+17‰ to +21‰) and pollution dominated modern cave drip waters (+1‰ to +5‰) and so we expect to see a strong secular trend whereby sulphur isotopic signatures depict increasing levels of pollution over the past 150 years. An increase in both sulphur concentration and δ34S values between input precipitation and cave drip waters, suggests the isotopic composition of sulphur available for incorporation into calcite is modified by the release of stored water as controlled by hydrological conditions. By determining site specific transfer functions, isotope ratios of sulphur within speleothems may be used successfully as an indicator of environmental and atmospheric change

Holocene climate variability in north-eastern Italy: Potential influence of the NAO and solar activity recorded by speleothem data

Here we present high-resolution stable isotope and lamina thickness profiles as well as radiocarbon data for the Holocene stalagmite ER 76 from Grotta di Ernesto (north-eastern Italy), which was dated by combined U-series dating and lamina counting. ER 76 grew between 8 ka (thousands of years before 2000 AD) and today, with a hiatus from 2.6 to 0.4 ka. Data from nine meteorological stations in Trentino show a significant influence of the North Atlantic Oscillation (NAO) on winter temperature and precipitation in the cave region. Spectral analysis of the stable isotope signals of ER 76 reveals significant peaks at periods of 110, 60–70, 40–50, 32–37 and around 25 a. Except for the cycle between 32 and 37 a all periodicities have corresponding peaks in power spectra of solar variability, and the 25-a cycle may correspond to NAO variability. This suggests that climate variability in northern Italy was influenced by both solar activity and the NAO during the Holocene. Six periods of warm winter climate in the cave region were identified. These are centred at 7.9, 7.4, 6.5, 5.5, 4.9 and 3.7 ka, and their duration ranges from 100 to 400 a. The two oldest warm phases coincide with the deposition of sapropel S1 in the Mediterranean Sea indicating that the climate in the cave region was influenced by this prominent pluvial phase in the Mediterranean area. For the younger warm phases it is difficult to establish a supra-regional climate pattern, and some of them may, thus, reflect regional climate variability. This highlights the complexity of regional and supra-regional scale Holocene climate patterns