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This paper investigates the relative influences of climatic and anthropogenic factors in explaining environmental and societal changes in the southern Alps, Italy. We investigate a deep sediment core (LL081) from Lake Ledro (652 m a.s.l.). Environmental changes are reconstructed through multiproxy analysis, that is, pollen-based vegetation and climate reconstruction, magnetic susceptibility (MS), lake level, and flood frequency, and the paper focuses on the climate and land-use changes which occurred during the late Holocene. For this time interval, Lake Ledro records high mean water table, increasing amount of pollen-based precipitation, and more erosive conditions. Therefore, while a more humid late Holocene in the southern Alps has the potential to reinforce the forest presence, pollen evidence suggests that anthropogenic activities changed the impact of this regional scenario. Land-use activity (forest clearance for pastoralism, farming, and arboriculture) opened up the large vegetated slopes in the catchment of Lake Ledro, which in turn magnified the erosion related to the change in the precipitation pattern. The record of an almost continuous human occupation for the last 4100 cal. BP is divided into several land-use phases. On the one hand, forest redevelopments on abandoned or less cultivated areas appear to be climatically induced as they occurred in relation with well-known events such as the 2.8-kyr cold event and the ‘Little Ice Age’. On the other hand, climatically independent changes in land use or habitat modes are observed, such as the late-Bronze-Age lake-dwellings abandonment, the human population migration at c. 1600 cal. BP, and the period of the Black Death and famines at 600 cal. BP. [ABSTRACT FROM AUTHOR]

Cross-cultural studies are particularly relevant in the context of climate change, given its pervasive character and the growing demand for climate change mitigation at both global and local levels. This paper reports on findings from comparative cross-cultural mixed-methods research eliciting perceptions of the future among citizens in Norwich (UK) and Rome (Italy). The paper explores how individuals at the two locations interpret socio-economic and climate scenarios, and how they relate environmental change to human behavior. Attitude segmentation was found to be similar in both localities. Although most participants in both locations realized the benefits of a future centered on sustainable resource use and societal welfare, individuals' attitudes and considerations about the future were not largely influenced by the scenarios. Discussions revealed that the credibility of the projections depended on individuals' prior beliefs and their trust in the science portrayed. [ABSTRACT FROM AUTHOR]

The recent rapid mass loss of mountain glaciers in response to climate warming has been reported for high and low latitudes all over the Earth. The paper analyses and discusses the recent evolution of a representative glacierized group within the Italian Alps, the Piazzi—Dosdè, where small glaciers are experiencing considerable retreat and shrinking. We analysed aerial photos to calculate area and geometry changes in the time window 1954—2003, and glaciological and geomorphological surveys were also performed. The estimated area change during 1954—2003 was —3.97 km2 (—51% of the area coverage in 1954). Area reduction increased more recently: area change during 1991—2003 (12 years) was —1.74 km2, against —0.67 km2 during 1981—1991 (10 years), and —1.57 km 2 during 1954—1981 (27 years). Moreover, analysis of the most recent orthophotos acquired during the summer of 2003 under exceptional conditions (i.e. total absence of snow cover) allowed observation and mapping of changes affecting glacier shape and morphology, including growing rock outcrops, tongue separations, formation of proglacial lakes, increasing supraglacial debris and collapse structures. Such processes cause positive feedbacks that accelerate further glacier disintegration once they appear. From a geodynamical perspective, the Dosdè Piazzi is now experiencing transition from a glacial system to a paraglacial one; areas where in the past the shaping and driving factors were glaciers are now subject to the action of melting water, slope evolution and periglacial processes. [ABSTRACT FROM PUBLISHER]

Here three glacier surface area records (years 1975, 1999 and 2005) available for Aosta Valley (western Italian Alps) have been synthesized. The 1975 data have been collected by previous authors who compiled the first Aosta Valley regional glacier database. The 1999 and 2005 surface area data were computed by the authors here combining registered colour orthophotos with differential GPS (DGPS) field measurements. The surface changes of 174 glaciers (those shared within the three records of data) were calculated to describe the recent evolution of a representative subset of Italian glaciers. Aosta Valley glaciers lost 44.3 km2 during 1975–2005, i.e. c. 27% of the initial area. Small glaciers contributed strongly to total area loss, and during 2005 147 glaciers (c. 84.5% of the studied ones) were smaller than 1 km2, covering 20.7 km2 (c. 17% of the total area), but accounted for 43% of the total loss in area (losing 19 km2 from 1975 to 2005). The area change rate accelerated recently (1999–2005: mean area loss of c. 2.8 km2/year; 1975–1999: mean area loss of c. 1.1 km2/year). We then analyse records (1975–2005) of temperature, precipitation and snow cover from three high-altitude (1332 m asl to 3488 m asl) stations within Aosta Valley, to investigate modified climate within the area. We find increasing temperature especially during late spring and summer, and substantially unchanged total precipitation, with marked reduction of snowfall, snow cover, number of snowfall events and duration of continuous snow cover, especially during spring and summer, likely driving shrinking of glacier coverage. [ABSTRACT FROM AUTHOR]

This study presents pollen-based climate reconstructions of Holocene temperature and precipitation seasonality for two high-resolution pollen sequences from the central (Lake Accesa, central Italy) and eastern Mediterranean (Tenaghi Philippon, Greece) regions. The quantitative climate reconstruction uses multiple methods to provide an improved assessment of the uncertainties involved in palaeoclimate reconstructions. The multimethod approach comprises Partial Least Squares regression, Weighted Average Partial Least Squares regression, the Modern Analogues Technique, and the Non-Metric-Multidimensional Scaling/Generalized Additive Model method. We find two distinct climate intervals during the Holocene. The first is a moist period from 9500 to 7800 cal. BP characterised by wet winters and dry summers, resulting in a strongly seasonal hydrological contrast (stronger than today) that is interrupted by a short-lived event around 8200 cal. BP. This event is characterised by wet winters and summers at Accesa whereas at Tenaghi Philippon the signal is stronger, reversing the established seasonal pattern, with dry winters and wet summers. The second interval represents a later aridification phase, with a reduced seasonal contrast and lower overall precipitation, lasting from 7800 to 5000 cal. BP. Present-day Mediterranean conditions were established between 2500 and 2000 cal. BP. Many studies show the Holocene to have a complex pattern of climatic change across the Mediterranean regions. Our results confirm the traditional understanding of an evolution from wetter (early Holocene) to drier climatic conditions (late Holocene), but highlight the role of changing seasonality during this time. Our data yield new insights into the aspect of seasonality changes, and explain the apparent discrepancies between the previously available climate information based on pollen, lake-levels and isotopes by invoking changes in precipitation seasonality. [ABSTRACT FROM AUTHOR]

The identification and characterisation of high-frequency climatic changes during the Holocene requires natural archives with precise and accurate chronological control, which is usually difficult to achieve using only 14C chronologies. The presence of time-spaced tephra beds in Quaternary Mediterranean successions represents an additional, independent tool for dating and correlating different sedimentary archives. These tephra layers are potentially useful for resolving long-standing issues in paleoclimatology and can help towards correlating terrestrial and marine paleoclimate archives. Known major tephras of regional extent derive from central and southern Italy, the Hellenic Arc, and from Anatolia. A striking feature of major Holocene tephra deposition events in the Mediterranean is that they are clustered rather than randomly distributed in time. Several tephra layers occurred at the time of the S1 sapropel formation between c. 8.4 and 9.0 ka BP (Mercato, Gabellotto-Fiumebianco/E1, Cappadocia) and other important tephra layers (Avellino, Agnano Monte Spina, ‘Khabur’ and Santorini/Thera) occurred during the second and third millennia BC, marking an important and complex phase of environmental changes during the mid- to late-Holocene climatic transition. There is great potential in using cryptotephra to overlap geographically Italian volcanic ashes with those originating from the Aegean and Anatolia, in order to connect regional tephrochronologies between the central and eastern Mediterranean. [ABSTRACT FROM AUTHOR]

The earliest daily barometric pressure readings were taken during the Maunder Minimum of Solar activity (1645-1715). In Italy, observations were made at Pisa over the years 1657-1658 by V. Viviani and A. Borelli, and at Modena during the year 1694 by B. Ramazzini. These readings have been recovered, corrected and adjusted to modern units. The early instruments used and their problems have been thoroughly discussed. Barometer observations recorded by John Locke in Essex (UK) during the year 1694 have also been recovered and corrected. Daily observations were recorded during the same period in Paris by L. Morin; these have previously been published by Legrand and Le Goff (1992: Les observations météorologiques de Louis Morin. Monographie No. 6, Direction de la Météorologie Nationale, Ministère de l'Equipement, de Logement et des Transports, 41 pp.). However, cross-comparisons with the Locke and Ramazzini data have shown that the Paris series needed a further correction to take into account instrumental error. Using these three corrected series, it has been possible to reconstruct the atmospheric circulation over Europe for the year 1694. An indication of the state of the atmospheric circulation can also be made by using the earlier observations recorded in Italy. A common feature of the two periods studied (1657-1658 and 1694) is that winters were characterized by higher pressure compared with the reference period 1961-1990, while the summers generally experienced lower pressure. This latter conclusion indicates that the Azores High was late or not well developed, favouring low temperature and frequent rain in the late spring and early summer. [ABSTRACT FROM AUTHOR]

A core retrieved from Lake Frassino (northern Italy) provided evidence of palaeohydrological change in this area during the last 14 ka. Lithological, malacological and, in particular, stable isotope composition of freshwater shells allowed the delineation of the main phases of lake evolution between the Lateglacial and Holocene. Lateglacial conditions were drier than the Holocene, although a wetter period was inferred before c. 14 ka. According to the oxygen isotope composition of freshwater shells, the Holocene showed a clear bipartition. The first part, which lasted from ∼ 9100 to 7000 yr BP, was drier and was followed by a rapid increase in humidity at ∼ 7000–6800 yr BP. Between ∼ 6800 and 5000 yr BP, there were wetter and more stable conditions, as indicated by smaller δ18O oscillations of Pisidium and Valvata shells. From c. 5000 to 2600 yr BP the record is characterized by larger fluctuations, which may indicate that short-term and particularly pronounced alternation of wet and dry periods occurred. [ABSTRACT FROM AUTHOR]

A stratigraphic sequence was identified in the Gran Sasso Massif (Central Apennines, Italy), consisting of alluvial sediments and buried soils. The soils, dated by the radiocarbon method, enabled various alluvial phases that have occurred in the last 2500 years to be chronologically framed. These phases were then correlated with the frequency of the Tiber floods at Rome and with the progradation of its delta. The phases of soil burial by alluvial sediments coincide with the periods of intense flooding of the Tiber at Rome (between the second century BC and the second century AD, between the sixth and the ninth centuries AD, and between the fifteenth and the nineteenth centuries AD) and with periods of strong progradation of the river delta. On the basis of the chronological correlation between alluvial phases, glacial variations, and oscillations in the levels of Lakes Fucino and Trasimeno, it was then possible to establish that, corresponding to the alluvial phases, the hydrological balance of the lakes was positive and, in two of the three cases, the increased flood frequency coincided with the phases of advance of the only glacier located in the Apennines. [ABSTRACT FROM AUTHOR]

Records of geomagnetic secular variation have been obtained from three cores recovered from the Salerno Gulf (southern Italy). High-resolution petrophysical and palaeomagnetic measurements enabled the reconstruction of a composite curve of geomagnetic palaeosecular variation (PSV), which is compared with the reconstructed PSV curve from Britain and with the French archaeomagnetic data of the last 2.1ka. The good agreement of the Salerno Gulf record with the above data confirms that our PSV record reaches back for some 9.0ka. In addition to a thick pumice layer originated during the Somma-Vesuvius eruption at AD 79, two other tephra layers were recognized, at about 1.3 and 3.0ka BP, that are probably also of Vesuvian origin. The comparison provides an initial chronological framework for assessing the increasing trend of sedimentation rate and its significant changes at about 2.7ka and 7.0ka BP. This variation in the deposition rate suggests a link with climatic changes recognized in the Mediterranean region. [ABSTRACT FROM AUTHOR]

Lacustrine sediments from Lago di Pergusa in central Sicily provide a Postglacial record of environmental change in the Mediterranean. Magnetic susceptibility measurements, lithofacies characterization and pollen analysis were carried out and integrated to obtain a better reconstruction of the past 11000 years. The chronology is provided by AMS radiocarbon dates on macrofossils or bulk sediment, and by a tephra correlative with a late-Holocene explosion from the Etna volcano. The transition period related to the present interglacial reafforestation, characterized by increasing humidity, started about 10700 years BP. The onset of the wettest conditions of the Postglacial occurred at about 9000 years BP and lasted until about 7200 years BP. Then a trend towards aridification began, leading to very dry conditions at about 3000 years BP. An unquestionable human impact on vegetation is found from 2800 years BP, although earlier land use cannot be excluded. As the climate had already induced change in the vegetation, the well-known human occupancy during the last three millennia did not produce strong effects on the environment. [ABSTRACT FROM AUTHOR]

In northern Italy, and especially in the Po Valley, instability phenomena such as hail and thunderstorms are mainly associated with the penetration of Atlantic disturbances, especially cold fronts, or prefrontal squall lines in the mid-seasons, and with the thermal convection of hot and moist air in the summer. Changes of their seasonal distribution may be considered as an index of anomalies in the synoptic pressure pattern, which determines the general circulation over Europe. Two different types of meteorological data have been analysed: (1) historical, non-specialist descriptions, taken from chronicles, annals or diaries after ad 1300, when people began to record, in addition to the most outstanding climatic events and natural hazards, minor observations including instability phenomena; (2) regular daily observations made by trained meteorologists after 1740. The historical descriptions show that in the Po Valley the highest thunderstorm frequency is in the summer, between June and August, but in the 1500s the distribution was anomalous. In that century, a broad maximum was found between March and August, and a secondary maximum was found in December. In the early period of observations made by trained meteorological personnel, i.e., 1740–1799, a summer maximum of thunderstorm frequency was found, almost equally distributed from June to August, followed by May and September. In the most recent period, i.e., 1940–1989, the seasonal distribution was very regular for three decades (1940 to 1969) with the mode in June, followed by July and August, and it then changed, with more late peaks. The historical written sources show that the seasonal distribution of hail was more homogeneous than thunderstorms. Hail was especially frequent in the summer, from June to August, except in the 1500s, when the seasonal distribution was practically one month earlier. In the early period of regular meteorological observations, hail was seasonally distributed less regularly than thunderstorms, with more skew and earlier in the year. The maximum frequency was in June, followed by April, May, July and August. In the most recent period, the distribution was still irregular, with marked fluctuations, the distribution being displaced later in the season. [ABSTRACT FROM AUTHOR]