الفهرس 
Dedication
Description of the Red SeaOnly 14 pages are availabe for public view
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Abstract
Global warming is one of the most pervasive threats to coral reefs. Increased or decreased global warming can have several negative consequences for coral reef mortality, slowed growth and diseases. The growth and subsistence of corals depend on many variables including, temperature, irradiance, calcium carbonate saturation, turbidity, sedimentation, chlorophyll concentration, sea level rise, salinity, pH, and nutrients. These variables influence the physiological processes of photosynthesis and calcification as well as coral survival.
Coral reef ecosystems in the Red Sea, like world reefs, have undergone a tremendous change due to environmental and anthropogenic factors. Coral bleaching is a very patchy phenomenon defined as the loss and expel of symbiotic zooxanthellae, distributed worldwide which mainly submit under the global warming effect. Over the last four decades the coral reef cover globally was dramatically under strong thermal effect events that’s caused coral bleaching and mortality. Also, due those events of the ocean temperatures rise, the coral reef diseases increased and widespread globally.
Satellite ocean color remote sensing is based on sensing the radiance exiting the ocean surface. Ocean color is a characteristic of seawater properties that are composed of phytoplankton, dissolved organic matter, suspended sediments, shallow seabeds, tides, circulation variability and classification of marine vegetation. Climatic factors and ocean color can be detected by marine remote sensing. Coral reefs provide an excellent case study of the application of marine remote sensing to a shallow coastal ecosystem that is spatially limited. Coral reefs exhibit high diversity, high productivity, and faces severe anthropogenic and climatic threats. Habitat mapping is a prerequisite for condition and resources assessment of any ecosystem which leads to the implementation of management practices. So, the remote sensing is a good tool to monitor and predict the past, the present and the future status of coral reefs health.
Geographic Information System (GIS) is a powerful tool to assemble, analyses, store, utilize, retrieve, manipulate and disseminate scientific and technical data and thus aid in decision making. Coral Reef GIS may act as baseline information to support managers in, for example in identifying multi-use marine protection areas, spatial and temporal processes characteristics of the coral reefs, monitoring coastal development, assessing environmental impacts of natural hazards or legislative decisions, oil spill contingency, planning or assessing potential risk zones of coral reefs.
Coral reefs are an essential part of the earth’s ecosystem. They are sensitive indicators of the health of marine environments and are important economically, providing people around the globe with food, jobs, coastal protection, and recreational opportunities. Many of the world’s reefs have been severely damaged over the past few decades due to a combination of factors including habitat destruction, land-based pollution, sedimentation, overfishing, vessel groundings, coastal development, disease, and climate change.
A few previous researches based on multispectral satellite images with high resolution, climatic and ocean color satellite images with moderately resolution studied the coral reef habitat mapping, land use/land cover, bathymetric mapping, change detection and climate change at Egyptian Red Sea. So, the present study was designed to fulfill this gap. Four studied cities were chosen for this purpose. The studied cities were chosen as an appropriate site for this study for these reasons:
1. Offshore reefs degradation increased at an alarming rate.
2. Fast touristic and industrial developments
3. Increasing of diving and water sports.
4. Absence of a global warming unit.
5. Increasing of overfishing at coral reef areas.
6. Lack of awareness of individuals and their personal behavior.
7. Absence of annually monitoring plans for coral ecosystem.
The main objective of this study is to use remote sensing tools for time series analysis of the climatic parameter and correlate them with hard coral reef cover at the Egyptian Red Sea. The specific objectives of this study are:
1) Change detection analyses of coral reef cover and Land use at the studied cities (Red Sea) during the period of 42 years extending from 1973 to 2015.
2) Annual bleaching observations of hard corals cover from 2013 to 2015 at four studied cities.
3) To compare the annual sea surface temperature with current coral bleaching observations from 2013 to 2015.
4) Bleaching events of the thermal stress anomalies through the time series analyses of SST from 2002 to 2015.
5) Time series analysis of SST, Chl-a, PAR, Kd, SSH and SSS to investigate weekly, monthly and annual variations means, climatology and anomalies at the studied cities of Red Sea (Ras Ghareb, Hurghada, Qusier and Marsa Alam).
6) Study correlation and regression between bleaching observations and other climatic parameters.