1. Planning For Future Weather Extremes
In New Jersey
Anthony J. Broccoli
Director, Climate and Environmental Change Initiative
Department of Environmental Sciences
Rutgers University
New Jersey Future Redevelopment Conference
New Brunswick, NJ
March 1, 2013

2. Recent extreme weather events
“Boxing Day Snowstorm” (Dec. 26-27, 2010)

3. Hurricane
Irene

4. October 2011 Snowstorm June 2012 Derecho

7. Hurricane/Superstorm Sandy
Sandy All previous tropical systems passing
within 50 miles of Atlantic City

8. Storm surge from Sandy

10. Three questions…
• What do we mean by “normal” climate?
• Is there a “new normal,” in which Sandy and
other recent extremes are harbingers of future
events?
• How can we prepare for future weather and
climate impacts?

11. What do we mean by “normal” climate?
• We use the term “normal” to describe the expected range of
conditions, including averages and extremes, at a location.
• This definition of normal arises from the concept of stationarity.
• Stationarity is the assumption that the future will be similar to
the past, in a statistical sense, and that we can estimate the
probability of future events (for example, a “100-year storm”)
from past records.
• Even in a stationary climate, weather events that are more
extreme than those on record can happen, because modern
weather records only extend back in time for a limited period.

12. Is there a new normal?

13. Climate Change 101: The Basics
• Combustion of fossil fuels (coal, petroleum, natural
gas) emits carbon dioxide into the atmosphere
(currently about 9 billion tons of carbon per year).
• Slightly less than half of the carbon dioxide remains in
the atmosphere; most of the remainder goes into the
ocean (causing ocean acidification).
• Increasing carbon dioxide heats the earth; global
temperatures have risen by 1.5-2°F during the past
century.
• Increasing temperatures also cause other changes in
climate and sea level.

14. What the science says…
• We do not know if hurricane activity (i.e., intensity, frequency, duration)
has changed systematically in the past. In the future, hurricanes will
probably increase in strength but their number will either decrease or
remain essentially unchanged.
• We do not know if severe thunderstorms and tornadoes have become
more frequent (because observational methods have improved) and future
trends are uncertain.
• Many areas have experienced upward trends in the number of heavy
precipitation events and it is likely that such trends will continue
throughout the 21st century.
• Record high temperatures and heat waves have been occurring more
frequently and they are expected to increase further during the 21st
century.
• The ongoing rise in sea level has raised the baseline for coastal flooding
from storm surge and the rate of sea level rise will likely accelerate during
the remainder of the 21st century.

15. Sea level trends along NJ coast
16 inches in 100 years
Projection for 2050: 9-24” (best estimate of 16”)
Projection for 2100: 20-58” (best estimate of 38”)
[Source: R. Kopp and K. Miller, Rutgers University]

16. Historic water levels at Sandy Hook
• >13.2 FT — October 29, 2012 (Sandy)
• 10.1 FT — September 12, 1960 (Hurricane Donna) / December 11, 1992.
• 9.8 FT — August 28, 2011 (Hurricane Irene).
• 9.7 FT — November 7, 1953.
• 9.4 FT — September 14, 1944 (Hurricane) / March 6, 1962.
• 9.0 FT — November 25, 1950.
• 8.9 FT — January 23, 1966.
• 8.8 FT — November 12, 1968.
• 8.7 FT — MAJOR TIDAL FLOODING BEGINS.
• March 29, 1984 / March 13, 1993.
• 8.6 FT — September 27, 1985 (Hurricane Gloria) / January 2, 1987 / October 31, 1991.
• 8.5 FT — April 13, 1961.
• 8.3 FT — February 19, 1972 / March 19, 1996 / March 13, 2010.
• 8.2 FT — October 18, 2009.
• 8.1 FT — January 31, 2006 / April 16, 2007.
• 8.0 FT — October 14, 1955 / December 26, 1969 / December 2, 1974 / April 16, 2011.
• 7.9 FT — August 31, 1954 (Hurricane Carol) / December 22, 1972 / October 25, 1980 / February 24, 1998 /
December 25, 2002 / November 14, 2009.
• 7.8 FT — October 14, 1977 / November 8, 1977 / March 3, 1994 / December 20, 1995 / January 29, 1998 /
March 30, 2010.
• 7.7 FT — MODERATE TIDAL FLOODING BEGINS.
• March 20, 1958 / October 22, 1961 / November 10, 1962 / December 25, 1978 / December 3, 1986 /
January 4, 1994 / December 13, 1996 / November 14, 1997 / January 3, 2003 / January 3, 2006 / February
12, 2006 / October 7, 2006 / May 12, 2008 / December 12, 2008 / May 17, 2011.
• 6.7 FT — MINOR TIDAL FLOODING BEGINS

17. The future will not be the same as the past
• “We never had floods like this before. We made
preparations but it didn’t do any good…”
• “There was no reason for us to think that the kind of
flooding that we actually experienced would happen there.”
• “We had flooding in areas we never had flooding before.”
• “...we've never had flooding before…The house has been in
the family since it was built in 1964 and there's never been
a problem with weather...ever.”
• “They thought they'd be safe because they'd never had
flooding before.”

18. How can we prepare for future
weather and climate impacts?
• Recognize that the past is not an adequate guide to what will
happen in the future (limited records, changing climate).
• Use information from climate model projections, with careful
interpretation, to develop an understanding of the effects of a
changing climate baseline.
• Focus on aspects of climate change that we understand with high
confidence (such as sea level rise) rather than those that are
more uncertain (such as changes in storm frequency/intensity).
• Develop improved methods for making projections of the effects
of climate change on high impact weather events.