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Comment by IsaacL | Hacker News Reader

Coastal cities are unlikely to be flooded in our lifetimes. We're looking at about 1m [1] sea level rise in 100 years, or 50cm in our lifetime. That means coastal cities will face more severe storms, not ending up submerged. [2]

"Pfeffer adds estimates of sea level rise due to thermal expansion and ice melting to calving approximations and concludes that SLR by the end of the century will range 0.8 to 2.0 m above present with an emphasis on the lower area of this range (Figure 7)."

[1] https://en.wikipedia.org/wiki/Future_sea_level#Sea-level_at_...

[2] http://uk.businessinsider.com/cities-exposed-to-rising-sea-l...

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> Coastal cities are unlikely to be flooded in our lifetimes. We're looking at about 1m [1] sea level rise in 100 years, or 50cm in our lifetime.

Thats true, but what most people don't know is that sea level rise don't necessarily mean catastrophic floods. A far bigger problem -- in our lifetime -- is aquifer salination, that is the intrusion of saltwater into coastal freshwater aquifers. This is already happening, in the Nile-valley, Benin and Cyprus but also in Louisiana and California.

When the salinity of coastal Freshwater aquifers reaches a critical level, growing crops in coastal areas can be all but impossible.

"That means coastal cities will face more severe storms, not ending up submerged. [2]"

How does that work? Coastal cities will have more than half a meter more water to deal with and additionally have to face larger more powerful storm surges on top of those 50cm. Don't forget at certain times of the year we see stronger tides.

I also wonder if in 2007, the IPCC were more optimistic about our ability to curb emissions and took into account some of the feedback looks which are kicking in?

Isn't Miami already having problems with flooding at high tide? It doesn't seem like it would take that big of a change from them to have flooding problems when it isn't high tide.

Miami Beach is already spending $400 million dollars to raise streets and build out a pumping infrastructure.

http://www.npr.org/2016/05/10/476071206/as-waters-rise-miami...

Yes, parts of Miami flood regularly. See http://www.newyorker.com/magazine/2015/12/21/the-siege-of-mi....

Moreover, Miami is built on porous limestone; sinkholes are everywhere (http://www.newyorker.com/magazine/2013/03/18/notes-from-unde...) and will grow whenever salt water pours in, so Miami sinks. They don't even need rising sea levels to make things worse there.

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