Throughout my college years, I’ve made many friends who came from all over the world. One of those friends became my best friend and his nationality is Indian. He would make it a habit to travel and visit India once every year or so. He would go on and on about how the living conditions there were drastically different than here in the U.S. He’d tell me how water would swallow up the streets in a matter of hours due to a combination of rainfall and river flow. It got me thinking: just how does climate change increase flooding overall, especially in far off countries around the world?
Just to give an estimate, approximately 21 million people worldwide are affected by river floods each year on average and that number could easily increase to 54 million in 2030 due to climate change. In total, there are 164 countries that are affected greatly by river floods alone. Out of those 164 countries, 15 countries make up around 80 percent of the total population that is affected, with India ranking as number 1 [Figure 1.1]. In fact, floods are very common in some parts of India, some floods can become deadly.
So what causes flooding overall and how does climate change affect it? Well, flooding usually occurs when there is a large increase in a volume of water carried by rivers, creeks and many other geographical features into areas where the water cannot be drained adequately. This buildup of water can be caused by a number of factors. For instance, heavy rainfall can contribute to surface water flooding due to its inability to be absorbed into the ground or drained fast enough. Coastal flooding can result in high tides thanks to storm surges and or sea levels rising. Poor infrastructure can be another cause of floods, essentially allowing a buildup of water to easily gather up and grow. Storms and Tsunamis can also come into play causing deadly floods to erupt in a matter of hours. In the U.S. alone, in the 20th century, floods caused more property damage and fatalities than any other type of natural disaster.
So why does this seem to be happening ever so often throughout the world? Well thanks to climate change the atmosphere is getting warmer very quickly over the years. According to the Intergovernmental Panel on Climate Change (IPCC), the atmosphere is about 0.75 degrees warmer than it was at the start of the century, which means it can hold 5-6 percent more moisture. This indicates that the more water there is in the atmosphere when it begins to pour will result in the amount of volume that rainfall will release. As we know sea levels are increasing in volume as well in effect to the polar caps melting over time due to the rising temperatures. Figure 1.2 shows how river floods are affecting 21 million people on average per year primarily caused by climate change.
With countries like India already suffering from repeated floods, how can any of us be prepared for flooding overall? Well, many countries already have implemented dam like systems that help block and contain heavy flows of water. Innovation has given birth to flood control systems like the water gate which “is a clever PVC device that uses the pressure of oncoming water to stabilize itself” (5 New Flood Prevention Products). Other devices like the Aquobex can be used and reused, acting as a shield to stop water in its tracks before it can enter owners home. Most notably, other than flood control devices, there is one free source tool that is very useful in predicting flood risk for a specific geographical unit. “The Aqueduct Global Flood Analyzer is a web-based interactive platform which measures river flood impacts by urban damage, affected GDP, and affected population at the country, state, and river basin scale across the globe” (Aqueduct Global Flood Analyzer). We also have the option to use satellites, which can be used to measure the moisture levels of soil indicating which parts of the land will effectively be less likely to absorb water and other weather forecasting systems that can predict rainfall in many regions.
As with most climate change issues, awareness has become the necessary first step in solving many of the related symptoms. India’s government has already teamed up with Google to improve flood management/awareness. I believe just like my friend told me his stories and experiences dealing with floods in India, it is my duty to share this information with others. Being aware that climate change is real and is affecting many parts of the world is an eye-opener in itself. Innovation has greatly helped battle the effects of climate change thus far but it only acts as a limiter, delaying the inevitable. Before you know it, you too can be roaming the streets with water knee-high and rising faster than you can travel.
World’s 15 Countries with the Most People Exposed to River Floods. (n.d.). Retrieved from https://www.wri.org/blog/2015/03/world-s-15-countries-most-people-exposed-river-floods
Five things to know about flooding and climate change. (2012, November 27). Retrieved from https://www.carbonbrief.org/five-things-to-know-about-flooding-and-climate-change