The key hazards that occur along coastal areas are coastal erosion, submersion, and saltwater intrusion. Coastal erosion is caused by wave action, tides, and storms and results in the wearing away of coastlines. Submersion happens when sea levels rise, flooding previously dry land. Saltwater intrusion occurs when denser saltwater moves inland underground, contaminating freshwater supplies. These hazards are exacerbated by events like cyclones and sea level rise due to climate change.

1. Marine And
Coastal
Processes

2. What are the hazards that usually occur along
marine and coastal areas?
• Coastal processes, such as waves, tides, sea
level changes, crustal movement, and storm
surges will result to coastal erosion, submersion,
and saltwater erosion.

3. COASTAL EROSION
• Is the wearing down of the coastlines by the movement
of the wind and water.
• Not a constant process .
• The rate of depends on other events such as cyclones.
• Cyclones carry the sediment away from the shoreline.

5. SHORELINES
• Play important role in the society for transportation,
fishing, and tourism
• Preventing coastal erosion is of utmost property
• There are three main classifications of stabilizing the
shoreline: hard stabilization, soft stabilization, and
retreat.

7. HARD STABILIZATION
• Is done by building structures that will slow down the
erosion on areas that are prone to erosion.
• Examples are jetties, sea walls, and breakwaters.
• Though they may slow down the erosion in one area, it
may hasten the erosion in other areas.

8. JETTIES

9. SEA WALLS

10. BREAKWATERS

11. SOFT STABILIZATION
• Includes the process of beach nourishment, wherein sand
from an offshore location is brought to an area with a
receding shoreline.
• It does not make use of structures like the ones used in
hard stabilization.
• Examples: Soil Bio-engineering
• Geotubes / Geotextiles
• Dunes

12. Soil Bio-engineering

13. Geotubes / Geotextiles

14. Dunes

15. RETREAT
• Is the option taken by residents near areas where coastal
erosion is already severe.
• Allows an area that was not previously exposed to flooding by
the sea to become flooded by removing coastal protection.

17. SUBMERSION
• Submersion happens because of the changes in the sea level,
specifically, when it rises dangerously above the normal level.
• Is all due to the increase in the global temperature which, in turn,
melts the glacial deposits and increases the overall sea level.
• Another factor that that may cause submersion is the vertical
movement of the plates. Landmasses can be uplifted, which can
also cause changes in the sea level. It can also be caused by
tsunamis and storm surges.

18. • Submersion is the sustainable cyclic portion of coastal
erosion where coastal sediments move from the visible portion of
a beach to the submerged nearshore region, and later return to
the original visible portion of the beach. The recovery portion of
the sustainable cycle of sediment behavior is (accretion).
• Submersion will most likely occur in reclaimed lands. These are
the areas that were originally part of oceans, riverbeds, or
lakebeds. This land is a low-lying flatland, so even a small rise in
a sea level can cause great damage on the land.

21. SALT WATER INTRUSION
• Is the movement of saltwater into the freshwater aquifer.
• Saltwater intrusion is the movement of saline
water into freshwater aquifers, which can lead to contamination
of drinking water sources and other consequences. Saltwater
intrusion occurs naturally to some degree in
most coastal aquifers, owing to the hydraulic connection
between groundwater and seawater.

22. • It is because saline water has a higher mineral content than
freshwater, it is denser and has a higher water pressure. As a
result, saltwater can push inland beneath the freshwater. Certain
human activities, especially groundwater pumping from coastal
freshwater wells, have increased saltwater intrusion in many
coastal areas.
• . Water extraction drops the level of fresh groundwater, reducing its
water pressure and allowing saltwater to flow further inland. Other
contributors to saltwater intrusion include navigation channels or
agricultural and drainage, channels, which provide conduits for
saltwater to move inland, and it can also make sea level
rise. Saltwater intrusion can also be worsened by extreme events
like hurricane storm surges.