TMC is an independent, primarily volunteer organization that relies on ad revenue to cover its operating costs. Please consider whitelisting TMC on your ad blocker or making a Paypal contribution here: paypal.me/SupportTMC

The Siege of Miami

Discussion in 'Energy, Environment, and Policy' started by SpiceWare, Dec 28, 2015.

  1. SpiceWare

    SpiceWare Member

    Joined:
    Sep 5, 2015
    Messages:
    197
    Location:
    Fresno, Texas
    Hadn't heard this before - apparently Miami's already experiencing flooding. Miami Beach has been installing pumps and raising their roads to compensate.

    The Siege of Miami

     
  2. AudubonB

    AudubonB Mild-mannered Moderator Lord Vetinari*

    Joined:
    Mar 24, 2013
    Messages:
    4,244
    Location:
    Denali Highway, Alaska
    That New Yorker essay is a very, very long piece with some good information, quite a fair amount of perspective from geohydrologists who know their material, and not a lot of misinformation. I had found useful the discussion of the problems inherent in Miami's substratum. This swiss-cheese-porous corraline limestone simply cannot effectively be sealed to block the incursion of saline ocean water from the terrestrial locations and wreaking havoc on two fronts. First, the raising of the water table to equilibrate with a rising sea level regardless of any dikes, etc., and second, because of the devastation of the freshwater aquifer and its effects on both the natural environment and man's water supplies.
     
  3. SwedishAdvocate

    SwedishAdvocate Active Member

    Joined:
    Jul 26, 2012
    Messages:
    1,648
    Location:
    Sweden, Earth
    #3 SwedishAdvocate, Dec 28, 2015
    Last edited by a moderator: Mar 13, 2016
    ...And here's what that looks like in motion picture:

    Skip to 4:12:

     
  4. AudubonB

    AudubonB Mild-mannered Moderator Lord Vetinari*

    Joined:
    Mar 24, 2013
    Messages:
    4,244
    Location:
    Denali Highway, Alaska
    Good visuals in that 7m clip. Note, however, that there was not any discussion regarding permeation of the seawater via an end-run - rather, an under-run - around (under) any seawalls. Miami Beach and all of south Florida can raise sea walls until they reach the top of skyscrapers - and still the sea will come in. Hydrodynamically, the only card that man has in south Florida is the hydrostatic pressure of fresh terrestrial water maintaining enough pressure to resist the pressure of seawater at any land/water interface.


    HOWEVER...even that is not enough. The single problem that balancing act can solve is keeping well water, etc., from becoming brackish or saline. Now, that's an important enough problem to resolve and it can be done...as long as freshwater drawdown is kept low enough so that the needed hydrodynamic pressure is maintained. BUT - that fresh water "piston" cannot keep any higher-level seawater away. If this is difficult to visualize, imagine a body of water - call it an aquarium, or water glass, or whatever you like. Place a barrier across half of it....but punch a lot of holes in the underwater portion of that wall to represent the porous nature of Florida's limestone. Now raise the level of the side you designate "ocean". Of course, effectively instantaneously the water level equalizes on both sides of your model sea wall.

    I've little interest in a bargain piece of south Floodrida, thank you very much.
     

Share This Page