We are seeing more and more stories about floods recently. There are two contributing causes of floods. Storms cause floods, and the floods are made worse because of rising sea levels. Most scientists agree that the increase in storms we are experiencing is due to changing weather patterns, and that these changing weather patterns are caused by global warming.
The rising sea levels are primarily the result of melting ice. There is a lot of ice on land surfaces. Some of it is in glaciers, and some of it is in ice caps on land. The ice caps are where the largest amount of ice that can melt into the oceans is located. This ice is slowly melting. This is causing some of the sea level rise. If all of the ice that is now frozen in ice caps on land were to melt, that would result in a sea level rise of about 200 feet.
We do not expect this to happen, but a lot of ice has already melted. We can see the results of that in more frequent floods in areas near the seas. For example, in the city of Miami Beach, Florida, high tides regularly flood roads near the shore. More alarmingly, ocean fish often come out of the storm drains onto the road.
The Warming of Oceans
Another cause of rising sea levels is that the oceans are getting warmer. Warmer water expands, and that is part of the reason for sea level rise. The warmer water also results in more storms such as hurricanes. The water vapor evaporated from warm water is actually what supplies the energy for hurricanes and some other storms.
The main reason that global warming is happening is because of greenhouse gasses in our atmosphere. The main greenhouse gas is carbon dioxide.
As you can see from this graph, the level of carbon dioxide in Earth’s atmosphere is rapidly increasing. When we burn fossil fuels, such as coal or oil, carbon is released in the form of carbon dioxide into the air. Carbon dioxide prevents heat in the Earth’s atmosphere from escaping into space. Most scientists think that this causes global warming, but not all people agree. However, even if the cause is not clear, the fact is that the world is getting warmer, and the sea levels are rising. So what can we do to protect our shore cities and other environments near the oceans?
Can we protect our shores?
There are some examples of how people have built structures that protect them from high water levels. For example, much of the country of Netherlands is actually below sea level and the water is kept off the land by an elaborate system of dykes and massive pumps to control the water. This has worked so far, but the sea level continues to rise. There may come a time when a storm surge causes the dikes to fail. The, the country could be flooded and suffer major destruction. Other places have installed protective devices to control rising water. For example, London, England, has installed a tide barrier to keep the water in the Thames River from rising too high during high tides.
All of these things provide some protection, but if the sea levels continue to rise, there will be large areas that will be flooded. It will not be possible to protect the many miles of low lying land that are near the oceans. Many of our largest cities are close to sea level, and large parts of them will be flooded. Since many people like to live close to the shore, when there is a storm that results in a large tidal surge, they will experience a lot of flooding and damage. We have already experienced the damage from more than one major hurricane. If there are many damaging storms, people will need to move to higher ground and not continue living near the current sea level.
Of course, not all people agree with the scientists. However, if the scientists are correct, we must try to limit the increase in the carbon dioxide level by not burning as many fossil fuels. In order to avoid large increases in carbon dioxide, we will want to use renewable, green energy that will not change the carbon levels. We cannot reverse the damage already done, but we can try to prevent more damage from occurring.
There are books and magazine articles in both Readorium Rising Reader and in Readorium Scholar that help students understand this complex issue.