Variazioni meteomarine recenti e climatologia dinamica nel bacino adriatico: primi risultati

Abstract Recent sea level variations are a key indicator of global climate change. Estimating sea-level rise is one of the most important scientific issues, with a potential large positive social impact. The Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC), underlines the importance of instrumental records to analyse recent sea-level changes. The relatively intense warming recorded throughout the latest 40 years - with widespread ice melting and relative glacial-hydro-isostatic rearrangement - has however induced global sea level rise ranging around 1.2-2.0 mm/yr. In the Mediterranean Sea, this value is significantly lower (approximately by 35%) than the global mean value. Likely, this is due to the Northern Atlantic Oscillation (NAO), inducing at the Adriatic latitudes an evident increase of atmospheric pressure and temperature, as well as of salinity variation; also taking into account the specific features of this almost closed shallow sea. However, relative sea level rise (RSLR) occurred along the entire shorelines of the Northern Adriatic Sea, locally interfering with land subsidence, both natural and man-induced, and eustasy. Their combined effect has produced relative ground settlements ranging from centimetres to meters. Aim of this study is to analyse the historic series of meteo-marine records for 12 measuring stations, belonging to the National Tidal Network organized by ISPRA, located between Trieste and Otranto in order both to verify trends in sea level variations and to identify the most significant storm events occurred from 2010 to 2015. Synoptic situations responsible for these intense events for each sector of the basin have been analysed too. Persistence of subtropical high pressure conditions alternated with higher frequency of cyclogenesis have been detected for almost every month on both the northern Adriatic basin and the medium and high Tyrrhenian; this most likely is due to the increase of sea surface temperatures: around at 0.8 °C in the last fifteen years. Keywords: climate change, rising average sea level, Adriatic Sea, cyclogenesis, storm surge

Analysis of recent meteorological configurations responsible for substantial snowfalls in the Trentine sector of the Adige valley bottom (eastern italian Alps).

Aim of this presentation is to analyse the synoptic conditions favourable to snowfall with more than 10 cm fresh snow cover in the bottom of the Trentine sector of the Adige Valley. Following the abundant and reiterated snowfalls in the study area during the 2005-2006 winter season and the many discomforts to the population and mainly to the road traffic, an accurate study of such events resulted necessary for a reliable forecast. The valley orientation in a NNE-SSW direction lets the Mediterranean warm-humid air masses to get in as far as the main headwater divide (Brenner Pass) and to make its climate relatively mild. Moreover, such humid air inflows bring mean annual precipitation of about 800-1000 mm that gradually decreses from the lower valley mouth to the main divide. The precipitation regime consists of rainfalls in spring and autumn whereas a strong absolute minimum occurs between December and Febraury when snowfalls are more likely on the valley floor. In fact, the vally is annually subjected to warm advection snowfalls, though infrequent and scarce, between November and mid April. The study area is about 80 km long with elevation ranging from 130 and 230 m a.s.l. All the snowfall events observed from 1980 to 2006 were analysed by using the data of the Civil Protection Authority of Trento Province, i.e. Trento Roncafort (194 n a.s.l.), Trento Laste (312 m a.s.l.), Rovereto (203 m a.s.l.) and Ala (197 m a.s.l.) meteo stations. Through the study and analysis of ground and at the 500 hPa geopotential meteo maps, satellite images, thermodynamic diagrams of the nearest sounding stations and the data of the nivometeorological stations, the synoptic types that characterised the snowfalls were studied and classified and a clusterisation was made. For each of the synoptic types defined the conditions for a quantification of the mean characteristic meteo parameters were anlysed in order to obtain a reliable forecast of intense snowfalls on the valley bottom

Escursione lungo il litorale “piceno”

Abstract At the end of the National Symposium “Coastal erosion: defense, adaptation or withdrawal?”, organized by the Italian National Group for the Research on Coastal Environment (GNRAC), a short (half day) excursion has been organized to visit the “picena” coast (i.e. the portion of Marche littoral to the south of the Conero Mt.): some key location of which are here synthetically described. Namely, some of the main features of the coastline in Porto Sant’Elpidio, Porto Recanati and Sirolo are described. Key words: Adriatic Sea, Marche Region, coastal erosio

Tendenza evolutiva della spiaggia della Riserva Naturale della Sentina (San Benedetto del Tronto, AP)

Abstract The Regional Natural Reserve “Sentina” stretches itself for some 1.7 km along the southernmost end of the littoral area of San Benedetto del Tronto (AP) at the boundary with Abruzzo; it hosts one of the very few costal dunes still preserved in the Marche Region. Its gravelly-sandy beach in still natural, but is bound to the north by a long series of emerged barriers and to the south by a long (more than 300 m) pier; these structures noteworthy influence the retreat of the shoreline. In the area, a long monitoring (starting from 2000) has been carried out in order to interpret and quantify the modification occurred on both the emerged and submerged beach. During this time span, the shoreline retreated every year: up to 2006 its retreat has been evaluated in 27.7 m, with a local maximum of 33.5 m, whilst for the following 6 years (notwithstanding an artificial nourishment in 2008) it continued to retreat by 22.2, as an average. Therefore, in 12 years wave erosion resulted in some 50 m of backing; this also implied the loss of about 42’000 m2 of coastal dunes. Therefore, it is logical to assume that if no relevant intervention will be carried out, standing the almost absent nourishment deriving from the solid load of the Tronto R., in the next future the Sentina area will suffer progressive coastal erosion, with severe backing of the shoreline and distruction of the coastal dunes. Keywords: coastal erosion, monitoring, “Sentina” Reserve, coastal dune

Gli effetti antropici nell’evoluzione storica della costa “Picena”

The historical evolution of the southern Marche shoreline (between the Conero promontory and the Tronto R. mouth) has been investigated comparing it with both natural and anthropic changes. The study started searching, georeferencing and digitizing in a GIS environment all the available historical maps and the observations deriving from archeological and documental findings, in order to reconstruct the position of the shoreline at different times, mostly for fluvial mouths. This allowed us to highlight that for the last two millennia anthropic interventions influenced coastal dynamics more than climate variations. For all the investigated sites a close relation between shoreline fluctuations and forestation/deforestation processes was clearly revealed. Among others, it emerged that river mouths progradation continued up to 1930, well after the end of the “Little Ice Age” (around 1850). The above relation is particularly striking for the last two centuries, for which we have both accurate maps and census of forested areas. During the XIX century, notwithstanding the warm climate favored slope protection, widespread deforestation resulted in a regular advance of shorelines (average rate about 4.95 m/y for the first half of the century and 1.08 m/y for the second half). The XX century featured a more irregular behavior with substantial retreat after the ‘30s: this derives almost exclusively from anthropic interventions in the river basins (construction of dams, river bed quarrying, river reshaping, abandonment of crops etc.) leading to a severe decrease of solid load. For the last few decades and at present, the most important factors driving the behavior of coastlines resulted to be the various interventions carried out along the beaches and in front of them to reduce erosion. Keywords: antropogenic impact, historical evolution, coastline, central-southern Marche, Adriatic Se

Preliminary analysis of relationships between covid19 and climate, morphology, and urbanization in the lombardy region (Northern Italy)

The coronavirus disease 2019 (COVID-19) pandemic is the most severe global health and socioeconomic crisis of our time, and represents the greatest challenge faced by the world since the end of the Second World War. The academic literature indicates that climatic features, specifically temperature and absolute humidity, are very important factors affecting infectious pulmonary disease epidemics - such as severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS); however, the influence of climatic parameters on COVID-19 remains extremely controversial. The goal of this study is to individuate relationships between several climate parameters (temperature, relative humidity, accumulated precipitation, solar radiation, evaporation, and wind direction and intensity), local morphological parameters, and new daily positive swabs for COVID-19, which represents the only parameter that can be statistically used to quantify the pandemic. The daily deaths parameter was not considered, because it is not reliable, due to frequent administrative errors. Daily data on meteorological conditions and new cases of COVID-19 were collected for the Lombardy Region (Northern Italy) from 1 March, 2020 to 20 April, 2020. This region exhibited the largest rate of official deaths in the world, with a value of approximately 1700 per million on 30 June 2020. Moreover, the apparent lethality was approximately 17% in this area, mainly due to the considerable housing density and the extensive presence of industrial and craft areas. Both the Mann-Kendall test and multivariate statistical analysis showed that none of the considered climatic variables exhibited statistically significant relationships with the epidemiological evolution of COVID-19, at least during spring months in temperate subcontinental climate areas, with the exception of solar radiation, which was directly related and showed an otherwise low explained variability of approximately 20%. Furthermore, the average temperatures of two highly representative meteorological stations of Molise and Lucania (Southern Italy), the most weakly affected by the pandemic, were approximately 1.5 °C lower than those in Bergamo and Brescia (Lombardy), again confirming that a significant relationship between the increase in temperature and decrease in virulence from COVID-19 is not evident, at least in Italy