Abstract. This study aims to characterise the rainfall exceptionality and the meteorological context of the 20 February 2010 flash-floods in Madeira (Portugal). Daily and hourly precipitation records from the available rain-gauge station networks are evaluated in order to reconstitute the temporal evolution of the rainstorm, as its geographic incidence, contributing to understand the flash-flood dynamics and the type and spatial distribution of the associated impacts. The exceptionality of the rainstorm is further confirmed by the return period associated with the daily precipitation registered at the two long-term record stations, with 146.9 mm observed in the city of Funchal and 333.8 mm on the mountain top, corresponding to an estimated return period of approximately 290 yr and 90 yr, respectively. Furthermore, the synoptic associated situation responsible for the flash-floods is analysed using different sources of information, e.g., weather charts, reanalysis data, Meteosat images and radiosounding data, with the focus on two main issues: (1) the dynamical conditions that promoted such anomalous humidity availability over the Madeira region on 20 February 2010 and (2) the uplift mechanism that induced deep convection activity.

Tourism plays a crucial role for the development of coastal areas. Despite the mildness of Madeira's climate, very hot days can occur during summer, a situation to which most tourists from northern Europe (the majority of foreign tourists) are poorly adapted. As sea breezes strongly contribute to moderate heat stress in urban environments, their influence on the thermal comfort on the island has been studied. Sea breezes occurred on 84 % of the days during the period under study (May to October 2006). They usually start around 09:30 h and end after 22:00 h, with an average duration of about 12:50 hours and a mean velocity of 2.9 m/s. Physiologically Equivalent Temperature (PET) was used to evaluate the thermal comfort of a sample of days during the summer of 2006. It was concluded that most of the sites in the city are "slightly comfortable" during normal days with sea breeze, but only shore sites and the highest green areas offer some comfort during hot days. Inside the city, the thermal perception is generally "hot" and strong heat stress can occur. As sea breezes are important to mitigate heat stress, some basic guidelines were presented: urban planners should take advantage of this wind system avoiding dense construction near the shoreline that would act as a barrier to the renewal of the air inside the city. In terms of tourism, planners and local authorities should provide solutions to mitigate the negative effects during hot periods, creating a system to warn and relocate more vulnerable tourists to places near the shore line, to the mountains, to gardens and air-conditioned buildings. In combination with other components (beauty of the island, gastronomy, cultural values and safety), climate information can be a factor of attractiveness to tourists. Zusammenfassung Der Tourismus spielt bei der Entwicklung von Küstengebieten eine wichtige Rolle. Trotz des milden Klimas von Madeira können im Sommer sehr heiße Tage auftreten und die meisten Touristen aus Nordeuropa sind an diese Situation wenig angepasst. Da der Seewind einen wichtigen Beitrag zur Minderung von Hitzestress in urbanen Gebieten leistet, wurde sein Einfluss auf den thermischen Komfort von Menschen untersucht. Während des Untersuchungszeitraums (Mai bis Oktober 2006) wurde der Seewind an 84 % der Tage festgestellt. Er beginnt normalerweise nach 9:30 Uhr und dauert an bis ca. 22:00 Uhr mit einer durchschnittlichen Dauer von 12:50 Stunden und einer Windgeschwindigkeit von 2.9 m/s. Die Physiologiscḧ Aquivalente Temperatur (PET) wurde zur Bestimmung des thermischen Komforts für den Sommer 2006 berechnet. Die Schwellenwerte des Zivilschutzes wurden für die Identifikation von Hitzeperioden verwendet. Es wurde festgestellt, dass die meisten Messtandorte der Stadt leichten Hitzestress bei normalen Tagen mit Seewind und nur Küstengebiete und Grünflächen thermisch komfortable Bedingungen aufweisen. Im inneren Bereich der Stadt wird die thermische Situation generell als "heiß" wahrgenommen, und sehr starker Hitzestress kann entstehen. Aufgrund der Tatsache...

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Abstract:It is a known fact in structural optimization that for structures subject to prescribed non-zero displacements the work done by the loads is not agood measure of compliance, neither is the stored elastic energy. We briefly discuss a possible alternative measure of compliance, valid for general boundary conditions. We also present the adjoint states (necessary for the computation of the structural derivative) for the three functionals under consideration. (C) 2011 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.