Coastal regions around the world are home to diverse industries, which create many jobs. They also host diverse ecosystems while attracting tourists. However, coastal regions are exposed to many climate-related hazards – rising sea levels, coastal erosion, high tide flooding, storm surges, inland flooding and tsunamis. The first three coastal hazards were already covered in the previous article and now we will discuss the rest.
Storm
When hurricanes and other severe storms move from the ocean toward land, low pressure and strong winds can push considerable volumes of water toward the coast. Storms can produce water levels much higher than a normal high tide, resulting in extreme coastal and inland flooding.
The most critical conditions occur when a storm arrives at the same time as a high tide. Hurricane Sandy in 2012 was an example of this, when the water level rose more than 20 feet above mean sea level. Local vulnerability to storms will depend, in part, on the shape of the ocean floor in that particular region. The National Hurricane Center provides many resources, including a series of maps for people in hurricane-prone areas that illustrate storm risk.
Water can cause severe damage to structures and buildings, as it weighs about 1,700 pounds per cubic yard. Therefore, when structures are exposed to large waves, they may not be able to withstand the resulting forces. Additional impacts from the storms include:
- Beach erosion
- Loss of property
- Damage to coastal habitats
- Undermining the foundations of infrastructure
- Drowning victims
Get a resilient design for your next construction project.
Inland floods
Inland flooding results from coastal storms that make landfall. By definition, it does not occur on the coast, but hazard experts still group it with coastal issues. The annual cost of damage caused by inland floods is greater than that of any other severe weather event and can have several causes:
- After rain falls for many days in a row
- After brief periods of intense precipitation
- Packs of snow melting quickly
- Dam failure
Basically, inland floods occur whenever the volume of water in the ground exceeds the capacity of natural and constructed drainage systems. After storms cause damage along the coast, they can still produce widespread rainfall and flooding as they move inland, as Hurricane Harvey did in 2017. As the global average temperature rises, the sea level rises. sea will increase the frequency and extent of storms. extreme flooding associated with coastal storms, even if the intensity of the storms remains the same.
Back-to-back coastal storms also increase the risk of inland flooding. For example, if an area is hit by two consecutive tropical storms, soils may become saturated with water and rivers may be close to overflowing. In many coastal areas, the severity of combined events has increased; for example, a storm, river overflow and heavy rainfall occur simultaneously.
Tsunami
A tsunami is a series of large ocean waves caused by sudden movement of the ocean floor, landslide, or volcanic activity. Tsunamis have a great destructive potential, constituting one of the most serious threats to coastal areas and communities.
As tsunami waves approach the coast, they begin to slow down and gain height. The magnitude of the wave will depend on the depth of the water and the slope of the coast. A tsunami seen from the shore can look like a wall of water moving at 20-30 mph, measuring 10 feet or more. Large tsunamis are rare, but; they have great destructive potential for coastal communities in their path. Unfortunately, there is no way to avoid a tsunami and there is no “season” – they can occur at any time of the day or night, in good or bad weather. They can also occur in any ocean or sea, but in most cases they occur in the Pacific Ocean. However, although they cannot be avoided, their impact on coastal communities can be mitigated:
- Proper planning
- Timely Notices
- Preparation and awareness strategies
- Effective and fast response
Current tsunamis occur on top of the 20 centimeter rise in global average sea level since 1900. By the year 2100, tsunamis will occur on top of another 20 centimeters of sea level rise, or up to 2 meters more in the worst-case scenarios. .
With the severity and frequency of extreme weather events, building resilience has gained importance in the construction sector. When resilient design is applied to a building, it becomes a more reliable shelter for emergency conditions.
