Unit:
Κατεύθυνση Πρόληψη και Διαχείριση των Φυσικών ΚαταστροφώνLibrary of the School of Science
Supervisors info:
Θ. Γκουρνέλος, Αν. Καθηγητής ΕΚΠΑ, Ι. Φουντούλης, Επ. Καθηγητής ΕΚΠΑ, Ν. Ευελπίδου, Λέκτορας ΕΚΠΑ
Original Title:
Μελέτη και μοντελοποίηση των πλημμυρών στην περιοχή του Καρλοβάσου - Σάμος
Summary:
Initially there was an extensive presentation of the current situation of the
island of Samos and then the theoretical framework developed analyzing the
various processes that take place in a flood event. A reference to hydrological
models and the effect assessment methods used was thoroughly described.
The aim of this thesis is to model flood hazard maps for Karlovasi area of
Samos island. The floods have great incidence on the island of Samos, having
devastating effects. Karlovasi area has a rich history as reference to flood
events. Frequent flooding event is due to the combination of many physical
parameters, that create conditions for expression of such phenomena and human
interventions that affect water flow in the area, always with negative
consequences.
The calculation and study of the physical parameters was based entirely on the
use of GIS (ArcMap) and their specialized tools (ArcHydro). There was a
significant contribution of GIS in the assessment of flood risk, for the
calculation of geometrical characteristics (including morphological indicators)
of the relief of the study area and watersheds. The methodology used was based
on processing spatial GRID models produced by the processing of the Digital
Elevation Model (DEM) of the study area. The DEM delivered from 20m elevation
contour curves which were digitized from topographical maps of 1: 50,000 of the
Military Geographic Service (MGS).
Then, the DTM was developed to simulate the river network and catchment of the
study area, using the ArcHydro tool. After comparing the generated river
network and the network deeply retained on topographical maps of MGS, the
result was considered satisfactory.
The methodology used for the synthesis of hazard maps was based on the
assessment of the morphological characteristics of the terrain of the study
area and parameters of hydrological basins. Main steps of the methodology
followed is first to calculate the energy of the river and subsequent the
determination of their flood risk. The energy of the river was calculated at
their estuary, as exit points of the water body.
Finally, to better identify areas that bear the greatest (always based on the
morphological characteristics) risk of flooding, were considered the same
morphological gradient of the relief on the grounds that the event of flooding
is favored in areas with very small morphological inclinations and not favored
in the other. Thus an additional calculation was made to produce flood risk
map, based on the value of the morphological slope, considering that in areas
with slopes over 10% have no meaningful detailed analysis.
Main subject category:
Natural disasters
Other subject categories:
Hydrology
Geomorphology
Databases and Information Systems
Cartogrpaphy
Keywords:
ArcMap, Karlovasi, Geographical information systems, Modelling, ArcHydro
