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Currents
April 2016
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is projected to be 31 to 61 Inches by 2100. For critical infrastructure projects with design lives in excess
of 50 years, use of the upper curve is recommended
with planning values of 34 inches in 2060 and 81
inches in 2100.
The National Aeronautics And Space Administration Jet Propulsion Laboratory (2015) has reported
the average global sea level has risen almost 3 inches
between 1992 and 2015 based on satellite measurements. Sea level rise in South Florida has been of
similar magnitude over the same period (NOAA,
2015) but is anticipated to outpace the global average due to
ongoing variations in the Florida
currents and Gulf Stream.
Projected sea level rise, especially by 2060 and beyond, has a
significant range of variation as a
result of uncertainty in future
greenhouse gas emissions and
their geophysical effects, the
incomplete quantitative understanding of all geophysical
processes that might affect the
rate of sea level rise in climate
models and the limitations of current climate models to predict the
future. As such, the work group
recommends that the Unified Sea
Level Rise Projection include three
curves, in descending order, the
NOAA high curve, the USACE
high curve and a curve corresponding to the median of the
IPCC Ar5 Rcp8.5 Scenario, with
specific guidance as to how and
when they should be used in
planning. This guidance document describes the recommended application of the projection as it relates to both high
and low risk projects and short
and longterm planning efforts.
Also, the work group recommends that this guidance be
updated every five to seven years
because of the ongoing advances
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