An overview of the Covid-19 effects on employment during 2020. Evidence from Cyprus, France, Spain, Greece, Italy, Malta, Croatia and Portugal

The report at hand follows the geography of Covid-19 and scrutinizes the impact of the subsequent mitigation policies on employment across countries, regions and the main sectors of economic activity for the Mediterranean EU (MED EU), providing valuable insights for the social, economic and geographical pandemic-induced effects. The countries that are being studied here are Cyprus, France, Spain, Greece, Italy, Malta, Croatia and Portugal

Smart Water Management for Irrigation Purposes: The SWSOIP Pproject

It seems that the future scenarios for water resources management are characterized by increasing demand and by the short-term unsustainability of many reservoirs in the Mediterranean basin. To address these scenarios, improved management of water resources was needed for water economy, and water recycling policies. Furthermore, agriculture characterized as the largest water user worldwide and the monitoring of the agriculture via remote sensing techniques is an enormous subject where it used for special scientific applications such as irrigation, precision farming, yield prediction, estimation of evapotranspiration etc. The main objective of this paper is to present the current situation of water resources in the Mediterranean region and present the methodology and main objectives of the SWSOIP project which aims to develop a smart watering system for the irrigation process based on the estimation of evapotranspiration using both in-situ data (spectroradiometric, LAI, CH and meteorological) and Sentinel satellite data

Geometrical Corrections SAR and Hyperspectral Satellite Remote Sensing Images Accuracy Determination of their Coregistration

178 σ.Τα τελευταία χρόνια η τεχνολογική ανάπτυξη έχει προσφέρει στην επιστήμη της Τηλεπισκόπησης πολλών διαφορετικών ειδών δέκτες. Η αυξανόμενη χρήση Τηλεπισκοπικών απεικονίσεων από διαφορετικών ειδών δέκτες επιβάλει την ανάπτυξη μεθόδων συμπροσαρμογής των δεδομένων αυτών. Στη συγκεκριμένη εργασία εξετάζεται η συμπροσαρμογή Υπερφασματικών με Συνθετικού Ανοίγματος RADAR απεικονίσεις (SAR). Αρχικά πραγματοποιήθηκε εκτενής θεωρητική ανάλυση του τρόπου λήψης των υπερφασματικών απεικονίσεων και της γεωμετρίας που τις περιγράφει. Στη συνέχεια αναλύθηκαν οι κυριότεροι μέθοδοι γεωαναφοράς και ορθοαναγωγής των απεικονίσεων αυτών. Για τις μεθόδους αυτές διερευνήθηκαν οι παράμετροι που μεταδίδουν αβεβαιότητες στις τελικές θέσεις των εικονοστοιχείων. Με την ολοκλήρωση της εξέτασης των υπερφασματικών απεικονίσεων αναλύθηκαν με αντίστοιχο τρόπο οι απεικονίσεις SAR. Ειδικότερα αναλύθηκε ο τρόπος λήψης τέτοιων απεικονίσεων και εξετάστηκαν ενδελεχώς τα γεωμετρικά στοιχεία που περιγράφουν το είδος αυτών των απεικονίσεων. Ιδιαίτερη βαρύτητα δόθηκε στην εξέταση του τρόπου μετάδοσης σφαλμάτων με βάση το τρόπο λειτουργίας του συστήματος και την αντίστοιχη γεωμετρία που διέπει τις απεικονίσεις. Στο τέλος της θεωρητικής ανάλυσης, αναπτύχθηκε ένα στατιστικό μοντέλο για τον έλεγχο της αξιοπιστίας των συμπροσαρμοσμένων δεδομένων. Η εφαρμογή του θεωρητικού υποβάθρου πραγματοποιήθηκε σε τρία δορυφορικά συστήματα. Το πρώτο αναφέρεται στον Υπερφασματικό δέκτη Hyperion, ενώ τα υπόλοιπα δύο αναφέρονται στους συνθετικού ανοίγματος radar δέκτες ENVISAT και ALOS. Οι διαδικασίες γεωαναφοράς και ορθοαναγωγής που περιγράφηκαν στο πρώτο τμήμα της εργασίας, εφαρμόζονται και αναλύεται διεξοδικά η ποιότητα των τελικών αποτελεσμάτων. Έτσι για τις γεωαναφερμένες απεικονίσεις προσδιορίζεται το σφάλμα με το οποίο έχουν ορθοαναχθεί στο χαρτογραφικό σύστημα αναφοράς Universal Transverse Mercator (UTM). Οι διαδικασίες γεωαναφοράς και ορθοαναγωγής των Υπερφασματικών απεικονίσεων έλαβαν χώρα στο λογισμικό πακέτο ENVI 4.5. Αντίθετα για την ορθοαναγωγή των SAR απεικονίσεων αναπτύχθηκε κατάλληλο λογισμικό, στο πλαίσιο αυτής της εργασίας, σε γλώσσα προγραμματισμού IDL 7.0. Προσδιορίστηκε το σφάλμα ορθοαναγωγής τους και εξετάστηκαν τα αποτελέσματα του προτεινόμενου στατιστικού μοντέλου συμπροσαρμογής. Βασικό συμπέρασμα της έρευνας αυτής είναι η ακρίβεια συμπροσαρμογής Υπερφασματικών και SAR απεικονίσεων με τη μέθοδο των ανεξάρτητων ορθοαναγωγών. Ακόμα τα αποτελέσματα του στατιστικού μοντέλου αποτελούν ισχυρό εργαλείο για τη σωστότερη επιλογή τηλεπισκοπικών δεδομένων προς ανάλυση και επεξεργασία.In the recent years the technological development has brought to the science of Remote Sensing many different types of sensors. The increasing use of Remotely Sensed images from different types of sensors requires the development of coregistration methods for these data. The current study examines the co-egistration of Hyperspectral and Synthetic Aperture RADAR images. Initially, an extensive theoretical analysis of the geometry of Hyperspectral and SAR images took place. Then the main methods of georeference and orthorectification for these images were described in detail. For these methods the parameters that mostly transfer errors to each pixel final position were investigated. Specifically for SAR sensors their operating modes were analyzed as well as their geometrical elements. Particular attention was given to examine the way that mathematical errors were transferred through the specific geometry. Also, a statistical model was developed in order to determine the level of reliability of the coregistered data. The theoretical background was applied on 3 satellite systems. The first system refers to the hyperspctral sensor Hyperion, while the other two refer to the Synthetic Aperture Radar sensors ENVISAT and ALOS. The quality of the final results was analyzed in detail. So for these georeferenced images the misallocation error was calculated. ENVI 4.5 program was used for the georeference and orthorectification procedures of the hyperspectral images. Moreover the orthorectification algorithm of the SAR data was developed in the IDL 7.0 language. After the production of georeferenced images the proposed statistical model was implemented and evaluated. The basic conclusion of this investigation is that it is possible to coregister hyperspectral and SAR images through independent orthorectification methods. Furthermore, the results of the statistical model are a powerful tool for the selection of the appropriate data.Δημήτρης Β. Συκά

A novel automated methodology that estimates the United Nations (UN) Sustainable Development Goal (SDG) 14.1.1.: Index of coastal eutrophication using the Copernicus Marine Environment Monitoring Service (CMEMS)

The aim of the SDGs is to help human activities be sustainable. The SDG14 "Oceans" targets at the stability and sustainability of marine ecosystems and their resources. Among its ten targets, the 1st refers to the prevention and the significant reduction of marine pollution of all kinds. To quantify the target, the 14.1.1 "Index of Coastal Eutrophication (ICEP) and Floating Plastic Debris Density" is introduced by UNEP. Currently, classified in Tier III, i.e. the methods and data sources for its estimation are not defined, whereas the type of information needed is defined. It is composed from two sub-indicators: Coastal eutrophication, and concentration of floating plastic. According to the Oslo-Paris Convention, "eutrophication means the enrichment of water by nutrients causing an accelerated growth of algae and higher forms of plant life.". The impact of this sub-indicator can be characterized as social (waters dangerous for health) and economic (fish/mussels die resulting to production losses), while it has legislation implications (Marine Strategy Framework Directive). Eutrophic areas are usually detected in coastal waters due to nutrient inputs from anthropogenic coastal and land activities. CMEMS uses EO data and in-situ measurements to model these types of information. In this paper we present a novel automatic methodology to calculate the SDG14.1.1.a in the regions of Iberia-Biscay-Ireland Seas. The methodology exploits CMEMS models of Phosphate-Nitrates-Silica-Chlorophyll and Water-Transparency to calculate a weighted indicator that segments waterbodies into four categories: Non-problem areas, tendency in eutrophication events, possibility of eutrophication events and problem areas. The indicator was calculated with respect to bathymetry and the Exclusive Economic Zones of the countries that are included in the region, while the temporal provision was weekly and monthly, aggregated from daily CMEMS products. Results indicate the distribution of problematic waters near high population density areas and river estuaries and the shallow waters' tendency in eutrophication events

Detection of marine fronts: a comparison between different approaches applied on the SST product derived from Sentinel-3 data

Fronts, which are sharp boundaries between distinct water masses, play a substantial role in managing biodiversity of marine species and preserving a resilient ecosystem. The overarching aim of this study is to compare different methodologies for detecting marine fronts. Many marine fronts are identifiable by their strong temperature gradient. For that reason, this study tests how two different edge detection methodologies (Laplacian and Canny) performs on detecting marine once applied on the Sea Surface Temperature (SST) product of the Sentinel-3 SLSTR instrument. In a few words, the results of this study showed that the Laplacian edge detection overestimates fronts, while the Canny Edge detection algorithm underestimates them. It worth highlighting though that the results are significantly improved using the appropriate filtering and/or image enhancements. The results of the Canny Edge detection algorithm were improved when a histogram equalisation image enhancement was applied before the Canny Edge and the results of the Laplacian detector were improved with median filtering