[Vision2020] Goddard Institute for Space Studies, April 2011: "Adapting to Sea Level Rise in New York City"

[Ted Moffett]

Imagine Moscow's mayor convening a Moscow City Panel on Climate Change
(MPCC), as did New York City mayor Bloomberg?  Of course, Moscow will
not be facing the direct impacts (indirect impacts, no doubt) of sea
level rise, one of the primary direct impacts of anthropogenic climate
change on NYC.  Instead, the Moscow City Council might offer a welcome
mat for climate change, advocating a new "Greening Earth Society" in
Moscow
http://www.sourcewatch.org/index.php?title=Greening_Earth_Society

"Moscow Council Gives Mega-load of Climate Change Green Light!" might
read the headline.

I'm not fully informed on all of the Moscow city efforts or statements
regarding climate change.  But in the Moscow Economic Development
Strategy Plan, Chapter 4: Constraints, Opportunities and Alternatives,
page 82 (
http://www.moscow.id.us/econdev/Chapter4.pdf ),
there is a footnote stating "Climate scientists agree that further
climate change may be inevitable." with a reference to a study
predicting temperature increases to 2050.

This footnote is misleading and grievously short-sighted.  Climate
scientists agree that further climate change is inevitable, not "may
be" inevitable (caps as is from US National Academy of Sciences
website):
STRONG EVIDENCE ON CLIMATE CHANGE UNDERSCORES NEED
FOR ACTIONS TO REDUCE EMISSIONS AND BEGIN ADAPTING TO IMPACTS
http://www8.nationalacademies.org/onpinews/newsitem.aspx?RecordID=05192010
Language suggesting a large uncertainty in the potential for future
climate change encourages inaction to address the problem.

And the physics of atmospheric CO2 emissions on climate change demand
considering the plausible magnitude of these impacts on a centuries
long time scale, given CO2 atmospheric lifespan and powerful positive
feedbacks in the Earth's climate system.

In 2050 Moscow could very well not be suffering tremendously from
climate change, but the increases in atmospheric CO2 level induced by
continuing immense fossil fuel use is likely by 2050 to induce further
and far more intense climate change, by 2100 and beyond.  Every
discussion of climate change should emphasize the plausible impacts of
our current behavior regarding fossil fuel use on a centuries long
time scale.

The public and private sector obviously is not equipped for long term
planning on a centuries time scale, that the science of climate change
indicates is required; but some nations are attempting:

Dutch to draft 200-year plan against warming

http://www.msnbc.msn.com/id/20689966/ns/us_news-environment/t/dutch-draft--year-plan-against-warming/
------------------
http://www.giss.nasa.gov/research/briefs/rosenzweig_03/

>From Goddard Institute for Space Studies website above:

"Recognizing that New York City faces potential impacts of climate
change, Mayor Michael Bloomberg in 2008 convened the New York City
Panel on Climate Change (NPCC), consisting of experts from the NASA
Goddard Institute for Space Studies; Columbia University, the City
University of New York, and other regional universities;..."

Science Briefs

More Floods Ahead: Adapting to Sea Level Rise in New York City

By Cynthia Rosenzweig, Vivien Gornitz, Radley Horton, Daniel Bader,
and Richard Goldberg — April 2011

Our planet is heating up, largely due to atmospheric build-up of
greenhouse gases since the onset of the Industrial Revolution. As
mountain glaciers melt, ice sheets thin, and oceans warm, sea level
rise is accelerating. As sea level rises, urban areas near the coast
like New York City will undergo more frequent and intense episodic
flooding following major storms, as well as permanent inundation of
some low-lying areas.

Accelerated sea level rise and exacerbated coastal flooding are issues
of critical concern for New York City and its broader metropolitan
region. With over 600 miles of densely populated coastline, this urban
environment is prone to losses from weather-related natural disasters.
NYC ranks in the top ten worldwide in population vulnerable to coastal
flooding, and is second only to Miami in port cities with assets
exposed to coastal flooding.

New York City currently experiences a number of coastal climate
hazards. In spite of its northerly location, the city is not immune to
tropical cyclones. In 1821, a hurricane that struck the city produced
a surge of 13 feet (about 4 m) in one hour and flooded lower Manhattan
as far north as Canal Street. In 1893, another hurricane flooded
southern Brooklyn and Queens, wiping out a small barrier island off
the Rockaways. During the 20th century, the "Long Island Express"
(1938) (see Fig. 1), Hurricane Donna (1960), and to a lesser extent,
Hurricane Gloria (1985) inflicted considerable damage on nearby Long
Island and New Jersey. Even winter storms, such as the nor'easter of
December 1992, can cause extensive flooding in low-lying neighborhoods
and seriously disrupt ground and air transportation.

Recognizing that New York City faces potential impacts of climate
change, Mayor Michael Bloomberg in 2008 convened the New York City
Panel on Climate Change (NPCC), consisting of experts from the NASA
Goddard Institute for Space Studies; Columbia University, the City
University of New York, and other regional universities; and the
private sector to advise the government of New York City on issues
related to climate change and adaptation (defined as steps taken to
reduce the impacts of climate variability and change) of critical
infrastructure (note 1). As part of the city's overall development of
policies for climate change adaptation, the NPCC provided information
on future risks stemming from changes in temperature, precipitation,
sea level rise, and extreme events.

In the NPCC's 2010 Foundation Report, Climate Change Adaptation in New
York City: Building a Risk Management Response, future sea level rise
was projected for New York City for a combination of seven global
circulation models (GCMs) and three emissions scenarios (IPCC SRES A2,
A1B, and B2). One set of projections, based on the methods used by the
Intergovernmental Panel on Climate Change (IPCC) for the 2007 Fourth
Assessment Report, include global contributions from thermal expansion
of the oceans and meltwater (glaciers, ice caps, and ice sheets).
Local terms include land subsidence and changes in local water height
(relative to the oceans as a whole) caused by changes in ocean
currents, temperature, salinity, and other factors.

Recognizing that GCM-based sea level projections may underestimate the
potential for accelerated ice sheet melting, the NPCC created
additional "rapid ice-melt" scenario projections. These projections
differ in the meltwater term and assume that glaciers and ice sheets
will melt at rates comparable to those at the end of the last Ice Age
— the 10,000-12,000-year period of rapid sea level rise starting
roughly 20,000 years ago — when sea level climbed at an average rate
of approximately 3-4 feet (0.9 to 1.2 m) per century (note 2).

The GCM-based projections show a sea level rise of 7 to 12 inches (18
to 30 cm) by the 2050s and 12 to 23 inches (30 to 58 cm) by the 2080s.
In the rapid ice-melt scenario, sea level jumps to 41 to 55 inches
(104 to 140 cm) by the 2080s (Fig. 2).

Rising sea level alone is expected to increase the frequency,
intensity and duration of coastal flooding. The one-in-100 year event
— a flood having a recurrence probability of once per century — is a
common measure of flood risk. The GCM-based sea level rise shrinks the
return period for the one-in-100 year flood to once in 15 to 35 years
by the 2080s. The return interval for the one-in-10 year flood event
is reduced to once in 1 to 3 years. Possible changes in storms
themselves are not included in this analysis, due to uncertainty in
how storm characteristics may alter in the future.

For New York City, a higher average sea level would exacerbate street,
basement, and sewer flooding and create more frequent transportation
disruptions. It would increase rates of beach erosion, necessitating
additional beach nourishment programs. Saltwater would encroach
further on freshwater sources, potentially causing structural damage
to infrastructure and compromising some drinking water sources on Long
Island.

Given that temperatures and sea level are already rising, the NPCC
recommended that New York City should begin adapting to climate change
today. Because changes in the amount of future sea level rise and
other climate variables are uncertain, an effective response requires
"flexible adaptation pathways" that can be adjusted periodically in
light of new information. Other important types of information to
monitor include changes in coastal population and infrastructure,
emerging evidence of climate impacts, changes in available
technologies, and costs of adaptation strategies.

The NPCC prepared three workbooks, each addressing different aspects
of the challenge:

Climate Risk Information, which includes projections for mean and
extreme events, sea level rise and storm surge. (Horton et al., 2010)

Adaptation Assessment Guidebook, which is designed to help city
agencies plan for future climate change, including sea level rise
(Major et al., 2010)

Climate Protection Levels, which outlines a general process for
developing a set of climate change-related design and performance
standards (Solecki et al., 2010).

Recommended steps included preparing an inventory of infrastructure
and assets at risk and linking adaptation strategies to capital and
rehabilitation cycles. As part of the risk and hazard management
strategy, current one-in-100 year FEMA flood zone maps and Coastal
Zone Boundaries for waterfront revitalization should be updated to
cope with a rising sea level (Fig. 3). Design standards for bridges
can also be revised to encompass higher water levels.

By monitoring current climate impacts, periodically updating climate
projections, and developing and testing adaptation strategies, New
York City can build and maintain climate resilience in the 21st
century.

References

Horton, R., et al., 2010: Climate Risk Information, New York City
Panel on Climate Change. Ann. New York Acad. Sci., 1196, 147-228,
doi:10.1111/j.1749-6632.2010.05323.x.

Major, D.C., and M. O'Grady, 2010: Adaptation assessment guidebook,
New York City Panel on Climate Change. Ann. New York Acad. Sci., 1196,
229-292, doi:10.1111/j.1749-6632.2010.05324.x.

Nicholls, R.J. et al., 2008: Ranking Port Cities with High Exposure
and Vulnerability to Climate Extremes: Exposure Estimates, OECD
Environment Working Papers, No. 1, OECD Publishing,
doi:10.1787/011766488208.

Rosenzweig, C., et al., 2011: Developing coastal adaptation to climate
change in the New York City infrastructure-shed: process, approach,
tools, and strategies. Climatic Change, 106, 93-127,
doi:10.1007/s10584-010-0002-8.

Rosenzweig, C., and Solecki, W. eds., 2010. Climate Change Adaptation
in New York City: Building a Risk Management Response. New York City
Panel on Climate Change 2010 Report. Annals of the New York Academy of
Sciences, v. 1196.

Solecki, W., Patrick, L., and Brady, M, 2010: Climate Protection
Levels, New York City Panel on Climate Change. Ann. New York Acad.
Sci., 1196, 293-352, doi:10.1111/j.1749-6632.2010.05325.x.

Contact
Please address all inquiries about this research to Dr. Cynthia Rosenzweig.

Footnotes

1 "Critical infrastructure" is defined as systems and assets
(excluding residential and commercial buildings, which are addressed
by other efforts) that support vital city activities and for which the
diminished functioning or destruction of such systems and assets would
have a debilitating impact on public safety and/or economic security.
(Back to text)

2 In this scenario, meltwater is assumed to rise exponentially from
the present mean ice melt rate of 0.43 in/decade (1.1 cm/decade)
between 2000 and 2004, reaching about 3 feet (1 meter) by the end of
the century. The meltwater term is added to the other three sea level
terms (i.e., thermal expansion, local land subsidence and local
changes in water height) which remain unchanged. (Back to text)
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Vision2020 Post: Ted Moffett