Sea level rise is the gradual increase of water level in the world’s oceans due to global warming. The emission of greenhouse gasses into the atmosphere causes the planet to warm up over time. This adds to sea level rise and other climate problems in the world.
WHAT CAUSES SEA LEVEL TO RISE?
The causes for sea-level rise may vary from one place to another. However, melting glaciers and thermal growth are the main drivers of sea-level rise in the world.
A glacier is a large body of ice formed over a long period of time. It can take up to 100 years for a glacier to form.
The largest glacier in the world is found in Antarctica. Greenland has the second-largest ice sheet on the globe.
Since the temperature levels on the planet are rising, the glaciers found in these regions are continuously melting. When ice melts, it turns into water and flows into the ocean.
Melting glaciers increase the volume of water in the ocean, resulting in sea level rise. The high rate of sea level rise is mainly attributed to melting glaciers.
Global warming causes the earth’s surface temperature to rise and this greatly affects the oceans.
The increase in atmospheric heat causes the water in the ocean to expand. This happens because the world’s oceans absorb over 90% of the heat that is brought about by global warming.
As the ocean water expands, the sea level rises. Due to the effects of global warming over the past century, the ocean is expanding rapidly.
Water is slowly invading coastal cities, thereby causing serious problems in different parts of the world.
Other Causes of Sea Level Rise:
Slowing Gulf Stream
The Gulf Stream refers to a strong ocean current that extends from the Gulf of Mexico to Western Europe. It pushes warm water along the eastern coastline of the United States and Canada.
The Gulf Stream is essential to the global climate. It moderates the coastal temperatures, thus keeping the sea levels in check.
Recent studies show that the Gulf Stream has slowed down due to climate change. This may bring about unprecedented changes in the weather patterns along the coastline.
Sea levels, especially in the Atlantic Ocean, are expected to rise as the Gulf Stream continues to slow down.
Land subsidence can be defined as the sudden or gradual sinking of a large mass of the earth’s surface. It is a common phenomenon in coastal areas.
When land that is bordering the ocean sinks, it can lead to a rise in sea level. This increases the chances of flooding in these areas.
Land subsidence mainly occurs due to human activities. The removal of subsurface water from the ground greatly adds to land subsidence.
The sinking of land can aggravate the problem of sea level rise. Many coastline cities are sinking due to subsidence.
SEA LEVEL RISE ESTIMATES
The rate of sea level rise is increasing at an alarming rate. As the planet gets warmer, the world’s ice glaciers are being melted and the ocean volume is increasing.
Since 1880, the global sea level has risen between 8 to 9 inches.
Research shows that the rate of sea level rise has more than doubled. Each year the volume of the ocean increases by a few inches. The change in the sea level may seem minimal but it can cause catastrophic events.
It is estimated that the global sea level will rise by not less than 12 inches above 2000 levels before the year 2100. This only applies if greenhouse gas emissions are minimized.
A high emission pathway may worsen the problem of sea level rise. The sea level is estimated to rise by about 8.2ft above 2000 levels by 2100 if global warming is not mitigated.
The rate of sea level rise by year varies depending on climatic conditions. Between 1880 and 2013, the global sea level rose by about 0.06 inches each year.
The twentieth century has witnessed a global sea-level rise rate of between 0.12-0.14 inches per year.
SEA LEVEL RISE NEW YORK
New York is one of the major cities that is threatened by sea level rise. The sea level in New York’s coastal areas has risen by approximately 9 inches since 1950. (Research from SeaLevelRise.org)
According to scientists, the sea level along New York’s coast is rising by about 1 inch every 7 to 8 years.
Land subsidence and slowing of the Gulf Stream are the main causes of sea level rise in New York.
More water is left on the East coast due to the slowed movement of the Gulf Stream. Large chunks of New York’s coastal land are gradually sinking into the ocean.
Due to the rise in sea levels, the coastal areas in New York often experience flooding during winter.
The sea level rise in New York is expected to accelerate in the coming years.
CONSEQUENCES OF SEA LEVEL RISE
Rising sea levels affect humans and the environment. The water in the ocean can impact terrestrial organisms in countless ways.
The rise in global sea levels increases erosion in coastal regions. Several beaches around the world have been eroded due to sea level rise.
Salinity refers to the amount of salt in a water body. Ocean water contains a lot of salt. If the ocean expands, the saltwater can contaminate subterranean aquifers on land.
Coastal areas experience flooding on regular basis. This occurs when storm surges push the already risen water onto land. The rise in sea levels can also cause tidal floods. Tidal flooding can occur even when there is no storm.
The best way to counter sea level rise is by reducing greenhouse gas emissions into the earth’s atmosphere.
Without greenhouse gasses, the glaciers won’t melt at an enhanced pace. Additionally, the ocean won’t absorb too much heat from the atmosphere. This means the volume of water will not increase as much compared to when the atmosphere has greenhouse gasses.
SEA LEVEL RISE IS SLOWLY SINKING OUR PLANET
The rise in global temperatures causes sea levels to rise at a high rate. Sea level rise affects both marine and terrestrial ecosystems. Cities located in coastal regions are slowly being engulfed by the ocean as the planet continues to warm.
If the emission of greenhouse gasses is not reduced, the planet will lose its ice sheets and glaciers. Consequently, coastal areas will be fully submerged underwater due to the increased ocean levels.