The findings of a recent study about flooding revealed that the percentage of people at risk from flooding has increased by a fourth since the year 2000. Moreover, the analyses of documented satellite images exhibited that the increase in the number of populations vulnerable to flooding incidents is mainly due to the surge in migration in the flood-prone areas.
The study concluded that while it is evident that climate change has been contributing to the severity and frequency of flooding incidents, demographic growth will increase the impact of flooding. The study mentioned that of all environmental disasters, flooding occurrences have had the most impact.
What the Study Analyses Revealed
Based on satellite images, the researchers were able to estimate the number of populations impacted by more than 900 floodings that occurred between 2000 to 2018. It presented data that shows more people have been migrating to flood-prone countries, instead of avoiding them.
Researchers estimate that about 34% of the population increased in geographical locations where most floodings occurred. While these seems confusing, a factor cited as growth driver in Dhaka, Bangladesh are the cheaper costs of low lands in flood prone areas.
As the main causes of flooding are snow, ice melt, heavy rainfall and tropical storms, it is expected that the percentage of flooding risk will continue to rise by 2030. Although about two percent of the floods were caused by dam breaches, they mostly occurred where a large populations are concerned. Researchers estimate that by year 2030, approximately 179.2 million people will be affected by floods within the 100-year zones because of demographic change
Data Analysis Also Showed Why Flood Preparation Plans Failed
In latest flooding events, China and Germany were hit with a record rainfall that overpowered their line of defences against flooding. According to the authors of the study, preparing for floods is quite challenging since the flood maps indicating where flood waters would possibly penetrate are only based on climate models.
However, the models do not have the ability to predict unexpected events like dam breaches. Also, the flooding simulations forgot to include infrastructure modifications and population growth, which posed significant limitations in their use for flood preparation plans.
An example cited by the study authors is the flooding that happened in Texas in 2017 caused by Hurricane Harvey. There was lack of preparation since the more than 80,000 houses that were flooded were not reflected on the state government’s risk maps. Therefore, the better approach in developing flooding simulations, is by using collected information pertaining to actual rainfall, elevation and data coming from ground sensors.