scholarly journals Extreme sea events during the last millennium in the northeast of Morocco

2015 ◽  
Vol 15 (2) ◽  
pp. 203-211 ◽  
Author(s):  
O. Raji ◽  
L. Dezileau ◽  
U. Von Grafenstein ◽  
S. Niazi ◽  
M. Snoussi ◽  
...  

Abstract. The Moroccan Mediterranean coast is located in one of the area's most vulnerable to extreme weather events or tsunami hazards. The objective of this research is to reconstruct the historical extreme submersion-event record using sea-induced deposits preserved in coastal lagoon. The Nador lagoon is the largest Moroccan lagoon (115 km2). It is located along the western Mediterranean, which has a high cyclogenetic character and is exposed to tsunamis from the Alboran Sea. The sandy barrier which separates the lagoon from the Mediterranean Sea is marked by much overwash, which indicate how intensely it has been exposed to the adverse sea events through history. Using the UWITEC© gravity coring platform, an undisturbed MC4.5 core (1.15 m long) was successfully sampled in the studied lagoon. To identify extreme sea events, a multi-proxy approach was applied combining sedimentological and geochemical data. Three paleoevents were identified; all of them are concentrated over the last 500 years, and the most recent event corresponds to the 1889 storm. For the others deposits, it is difficult to determine exactly their origin; however, the high frequency of storm events over the relevant period and the absence of historical tsunamis evidence is more in favor of the meteorological origin.

2014 ◽  
Vol 2 (3) ◽  
pp. 2079-2102 ◽  
Author(s):  
O. Raji ◽  
L. Dezileau ◽  
U. Von Grafenstein ◽  
S. Niazi ◽  
M. Snoussi ◽  
...  

Abstract. The Moroccan Mediterranean coast is located in one of the most vulnerable area to extreme weather events or tsunami hazards. The objective of this research is to reconstruct the historical extreme submersion-events record using sea-induced deposits preserved in coastal lagoon. The Nador lagoon is the largest Moroccan lagoon (115 km2) located along the Western Mediterranean which presents a high cyclogenetic character and is exposed to tsunamis from Alboran Sea. The sandy barrier which separates the lagoon from the Mediterranean Sea is marked by many overwashes, which indicate how intensely has been exposed to the adverse sea events through history. Using the UWITEC coring platform, an undisturbed MC4.5 core (1.15 m long) was successfully sampled in the studied lagoon. To identify sea extreme events, a multi-proxy approach was applied combining sedimentogical and geochemical data. The preliminary results show that the identified paleo-events are concentrated over the last 500 years. The challenge that remains now is to distinguish between the tsunami and the storm deposits.


Water ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 377 ◽  
Author(s):  
Asensio-Montesinos ◽  
Pranzini ◽  
Martínez-Martínez ◽  
Cinelli ◽  
Anfuso ◽  
...  

Sand colour can give important information about mineral composition and, consequently, sediment source areas and input systems. Beach appearance, which is mostly linked to sand colour, has a relevant economic function in tourist areas. In this paper, the colour of 66 sand samples, collected along both natural and nourished beaches in the western Mediterranean coast of Spain, were assessed in CIEL*a*b* 1976 colour space. The obtained results showed relevant differences between natural and artificially nourished beaches. The colour of many nourished beaches generally differs from the native one because the origin of the injected sand is different. The native sand colour coordinates’ range is: L* (40.16–63.71); a* (−1.47–6.40); b* (7.48–18.06). On the contrary, for nourished beaches’ the colour range is: L* (47.66–70.75); a*(0.72‒5.16); b* (5.82–18.82). Impacts of beach nourishment on the native sand colour were studied at San Juan beach, the most popular one along the study area. Nourishment works were performed after severe erosion, usually linked to anthropic activities/structures and storm events, but also to increase beach width and hence benefit tourism.


2020 ◽  
Vol 104 (2) ◽  
pp. 1695-1704
Author(s):  
Hanna Huitu ◽  
Kim Kaustell ◽  
Matti Pastell

Abstract Due to technological advancement, agricultural production is increasingly dependent on electricity. At the same time, power delivery infrastructures are challenged by extreme weather events. Losses in primary food production due to electrical outages are still largely unquantified. This paper reports the effect of storm-induced power outages on milk production in Finland. The study used detailed, farm-level records of power cuts from 2010 to 2015 available from two power companies and contrasted them to the respective monthly milk production statistics collected at farm level. For each major storm event, deviation in the milk production compared to previous month was calculated for each farm. Effect of power outages onto milk production was estimated using linear mixed modeling. Power outages mainly occurred during and after storm events, and dairy farms experienced more outages than what was a national average for rural power customers. The power outages decreased the monthly milk yield of the most affected farms by 4.6% (farms experiencing outages longer than 72 h), and production recovered already for the month following the storm event. The results imply that milk production in Finland is prepared and resilient toward power outages shorter than 3 days and that the current magnitude of power outages in dairy farms is higher than what was known previously.


PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3360 ◽  
Author(s):  
Guilherme N. Corte ◽  
Thomas A. Schlacher ◽  
Helio H. Checon ◽  
Carlos A.M. Barboza ◽  
Eduardo Siegle ◽  
...  

Climate change is predicted to lead to more extreme weather events, including changes to storm frequency, intensity and location. Yet the ecological responses to storms are incompletely understood for sandy shorelines, the globe’s longest land-ocean interface. Here we document how storms of different magnitude impacted the invertebrate assemblages on a tidal flat in Brazil. We specifically tested the relationships between wave energy and spatial heterogeneity, both for habitat properties (habitat heterogeneity) and fauna (β-diversity), predicting that larger storms redistribute sediments and hence lead to spatially less variable faunal assemblages. The sediment matrix tended to become less heterogeneous across the flat after high-energy wave events, whereas β-diversity increased after storms. This higher β-diversity was primarily driven by species losses. Significantly fewer species at a significantly lower density occurred within days to weeks after storms. Negative density and biomass responses to storm events were most prominent in crustaceans. Invertebrate assemblages appeared to recover within a short time (weeks to months) after storms, highlighting that most species typical of sedimentary shorelines are, to some degree, resilient to short-term changes in wave energy. Given that storm frequency and intensity are predicted to change in the coming decades, identifying properties that determine resilience and recovery of ecosystems constitute a research priority for sedimentary shorelines and beyond.


2019 ◽  
Vol 53 (5) ◽  
pp. 399-416
Author(s):  
V. M. Tytar ◽  
Ya. R. Oksentyuk

Abstract In this study an attempt is made to highlight important variables shaping the current bioclimatic niche of a number of mite species associated with the infestation of stored products by employing a species distribution modeling (SDM) approach. Using the ENVIREM dataset of bioclimatic variables, performance of the most robust models was mostly influenced by: 1) indices based on potential evapotranspiration, which characterize ambient energy and are mostly correlated with temperature variables, moisture regimes, and 2) strong fluctuations in temperature reflecting the severity of climate and/or extreme weather events. Although the considered mite species occupy man-made ecosystems, they remain more or less affected by the surrounding bioclimatic environment and therefore could be subjected to contemporary climate change. In this respect investigations are needed to see how this will affect future management targets concerning the safety of food storages.


Author(s):  
Sergio A. Molina Murillo

Most scenarios indicate that people in developing countries are more vulnerable and less capable of adapting to climate change. Since our public understanding of risk toward climate change in developing countries is limited, this article presents results from Costa Rica and Nicaragua, two countries which are socio-economically distinct, but which are expected to suffer similar extreme weather events. From October of 2008 until May 2010, a total of 1,047 respondents were surveyed in cities of both countries. The main results indicate that climate change is a widely known concept but other notions such as “carbon footprint” are foreign to most respondents. Despite the general concern with its negative consequences, respondents’ foremost concern is linked to their socioeconomic situation, and how it will be impacted by climate change in such aspects as poverty and social security. The results presented here contribute to advance national and international policies aiming to support mitigation or adaptation strategies in developing countries.


2018 ◽  
Author(s):  
Peter C. Balash, PhD ◽  
Kenneth C. Kern ◽  
John Brewer ◽  
Justin Adder ◽  
Christopher Nichols ◽  
...  

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