World, US, and California Flood Maps
We use the online Climate Central flood map data at ss2.climatecentral.org to generate flood maps for California, the US, and the World. In general, we start with the 6 foot flood maps, and go lower when there is significant damage with less flooding.
The business as usual scenario for global warming predicts 2-4 feet of sea level rise by 2100. However, research on mechanisms of Greenland or Antarctic land ice melting may increase this up to 6 feet. Besides the background of sea level rise are storm surge, extreme rainfall, flooding from rivers upstream, and extreme tides. Even if these events and their combination are rare, you only need ONE such event to cause extreme damage. Oh, and I forgot levee breaks.
With business as usual, the recent US climate risk report estimated $118 billion of coastal damage yearly by 2090 for the US. Currently, we have many hurricanes which have cost tens of billions of dollars of damage. With RCP4.5, where we cut present greenhouse gas emissions in half, by the entire planet (!), we only reduce the 2090 cost by 22%.
The US and California flood maps are on this Flickr album .
The World flood maps are on this Flickr album.
The Climate graphs come from my Flickr album from the US Climate Impacts, Risks, and Adaptation Report:
I have only started exploring different areas, and expect to add more. If you have an area of interest, please add a comment to a photo on my Flickr account. Any mistakes in the locations of the maps are mine alone.
Some of the most vulnerable flood areas are river deltas, such as New Orleans for the Mississippi River. These areas are also first settled because they are natural ports and river commerce channels. They have fresh water, and cooling water for power plants. The delta land is flat for building cities and streets.
The US West Coast is cliffy, hilly, and mountainous due to collision of the Pacific Plate with the North American plate. Again, cities are built on the flat river outlets as in Los Angeles and the Bay Area.
The US East Coast is well eroded and flat, the Chesapeake Bay is also an easily flooded region, as is the Gulf coast.
Among other prominent river deltas are the Thames delta, the Nile delta north of Cairo near Alexandria, the Amazon delta, and the Yangtze River delta.
Many of the areas that appear to be flooded at 6 feet are already National Parks wetlands or preserves, in many countries.
The green areas on the US map are enclosed areas, where you have to worry about breaching levees. These do not seem to be mapped outside of the US. The black dots with circles around them are tide gauges.