6,855 research outputs found
The frequency of Adriatic surges and the solar activity
No full textTechnical Note 194, CNR - ISDGM, Venezia (ITALY
A possible Mediterranean 'tsunami' on August 14, 2003
No full textTechnical Note 199, CNR - ISMAR, Venice, Ital
Revisiting harmonic constants for the Northern Adriatic
No full textTechnical Note 193, CNR - ISDGM, Venezia, ITAL
Observations on the principal Adriatic seiche as indicator of variability and on the period of the smallest one.
No full textForecasting the water level in Venice: physical background and perspectives.
No full textINTRODUCTION
The exceptional flood of 4 November 1966, marked
a milestone in the international concern for Venice,
and this is also true for the efforts for the quantitative
forecasting of the water level in the lagoon.
Around 1970 the interest in this challenge involved
many scientific centres all around the world, so that
in 1972 the oceanographer W. Munk reported thirteen
research institutes developing prediction techniques
for Venice (Munk and Munk, 1972). The results
were significant, even though the complexity of the
problem does not allow, even today, the claim that a
definitive solution has been found.
Over the years, these research interests have been
paralleled by the development of questions from an
operational point of view. The historical Hydrographic
Office of the Magistrato alle Acque is complemented
by a service of the city of Venice, the Centre for Tides,
committed to alerting the city, initially by using sirens,
and, step by step, by the various modern tools of high
technology, like the internet and the Short Message
System (SMS). Moreover, a deeper interest has grown
from the perspective of the mobile barriers, for which
a long-term forecast becomes important. It is not correct
to say that the need for prediction is limited to
flood events. For a town like Venice, for example, the
very low tides are also dangerous; one thinks of their
effect in each ‘rio’ (small, internal canal), on commercial
traffic and much more on the rescue boats. Many
considerations force a general request for the forecasting
of all water levels, including the intermediate ones
(Boarto et al., 2001)
Sea Surges in Camargue: Trends over the 20th century.
No full textContinental Shelf Research 27 (2007) 922–934
Sea surges in Camargue: Trends over the 20th century
A. Ullmanna,b,, P.A. Pirazzolic, A. Tomasind,e
aUFR des Sciences Ge´ographiques et de l’Ame´nagement, Universite´ d’Aix-Marseille I, Aix en -Provence, France
bCEREGE—UMR 6635, Aix en Provence, France
cCNRS-Laboratoire de Ge´ogrphie Physique, 1 place Aristide Briand, 92 195-Meudon, France
dCNR-ISMAR, Venezia, Italy
eUniversita` di Venezia, Venezia, Italy
Received 8 November 2005; received in revised form 24 November 2006; accepted 4 December 2006
Available online 25 January 2007
Abstract
The vulnerability to short-term and long-term sea-level rises is particularly high in subsiding deltaic areas, especially in
microtidal seas, when surges (the differences between the observed sea heights and the simultaneous astronomical tide) are
frequent. At the Grau-de-la-Dent tide-gauge in the Camargue (Rhone delta, France), daily sea-level records are available
since 1905. Hourly tide data spanning the period 1979–1995 were obtained through the digitisation of the original paper
records: the local harmonic constants and the surges for the whole 20th century have been computed from these hourly
observations. It appears that the annual maximum observed sea-level height increases by 4 mm/yr at a rate that is two
times faster than the average observed relative sea level. The increasing trend of the annual maximum positive sea surges
(+1.9 mm/yr), which is equal to the average relative sea-level rise, is thus responsible for this difference. The most
important meteorological factor associated with local sea-surge occurrences is wind blowing from 1001 to 1201 sectors,
which tends to push the water toward the coasts. Since 1961, the frequency and the speed of wind from this sector
increased, although with some variability, thus contributing in part to the increase in the frequency and intensity of the
surges. Due to the changing hydrodynamics phenomenon in the Camargue, a positive feedback mechanism between
extreme marine events and shoreline regression is another factor to explain the sea-surge rise over the long term. The
increase in sea-surge frequency and height during the last century is especially of concern in the deltaic area if the nearfuture
global sea-level rise predicted by climate models is also taken into account.
r 2007 Elsevier Ltd. All rights reserved.
Keywords: Sea level; Surge; Tide; Wind; Flooding risk; Camargue; Rhone delta
1. Introduction
Any rise in sea level will have adverse impacts
such as coastal erosion and flooding, depending on
the time scale and the magnitude of the rise and the
human response to it (Paskoff, 1993). A rise in sea
level may be due to several factors acting on various
time scales, i.e., atmospheric storms (Bouligand and
Pirazzoli, 1999; Pirazzoli, 2000; Trigo and Davies,
2002; Pirazzoli and Tomasin, 2002), river flooding
in estuaries (Svensson and Jones, 2002), but also
land sinking or similar non climate-related changes,
linked to sediment compaction, isostasy, coastal
geomorphologic evolutions or urban development.
ARTICLE IN PRESS
www.elsevier.com/locate/csr
0278-4343/$ - see front matter r 2007 Elsevier Ltd. All rights reserved.
doi:10.1016/j.csr.2006.12.001
Corresponding author. CEREGE, Europoˆ le Me´diterrane´en
de l’Arbois, B.P 80, 13545 Aix-en-Provence, France.
E-mail address: [email protected] (A. Ullmann)
Resource Allocation for Secret Key Agreement over Parallel Channels with Full and Partial Eavesdropper CSI
No full text- …
