# Presentation: 474138

## Confronting Climate Change in New Jerseyand the Northeast Peter C. Frumhoff Union of Concerned Scientists Princeton Plasma Physics LaboratoryPrinceton, NJ30 January 2008

- Confronting Climate Change in New Jerseyand the Northeast* *Peter C. Frumhoff Union of Concerned Scientists* **Princeton Plasma Physics Laboratory**Princeton, NJ**30 January 2008*

## Global Average Temperature

- Washington Post

-  NOAA

-  NASA

- Source: IPCC *Climate Change 2007: The Physical Science Basis*—Summary for Policymakers.     

**Global Average Temperature**

**Global Average Sea Level**

**Northern Hemisphere Snow Cover**

**1850**

**1950**

**1900**

**2000**

**Notes:**
The IPCC concludes that it is “unequivocal” that Earth’s climate is warming, “as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global mean sea level.”

## Global Average Surface Temperature

- Source: IPCC *Climate Change 2007: The Physical Science Basis*—Summary for Policymakers.

**Global Average Surface Temperature**

**Notes:**
The black line represents observed surface temperature changes for the globe (based on temperatures recorded by
measuring stations around the world). The blue band represents how the climate would have evolved over the past century in response
to natural factors only (according to 19 computer simulations derived from five different climate models); the brown band represents
how the climate would have changed in response to both human and natural factors (according to 58 computer simulations derived from
14 different climate models). The overlap of the brown band and black line suggests that human activity very likely caused most of the
observed increase since the mid-20th century. Temperature change is plotted relative to the corresponding average for the 1901 to
1950 time period. Source: Climate Change 2007: The Physical Science Basis—Summary for Policymakers.

## Climate across the Northeast is also changing

- Annual temperatures have warmed ~ 2oF since 1970
- Winters have been warming fastest, at 1.3oF per decade since 1970
- Winter snowpack is decreasing
- Plants are flowering earlier in the spring
- More frequent extreme heat days in summer
- Rising sea surface temperature (1oF since 1900)

**Notes:**
I’ll assume this is where I start

## Available for download at: http://www.climatechoices.org 

- Available for download at: http://www.climatechoices.org

## Institutions of 

- University of Southern Maine

- Columbia University, CUNY, NASA-GISS

- Princeton University

- Wesleyan University

- Woods Hole Oceanographic Institution, Marine Biological Laboratory

- Bigelow Laboratory for Ocean Sciences

- University of  New Hampshire

- Colby College

- Cornell University

- Harvard University, Tufts University, Wellesley College, UMASS -Boston

- UMASS -Amherst

- Vermont Center for EcoStudies

- Institutions of
- NECIA Collaborators

- National Center for Atmospheric Research
- Texas Tech University
- University of Illinois – Urbana-Champaign
- University of Waterloo, Canada
- USDA - Beltsville

## Northeast U.S. Emissions:

- Significant on a Global Scale

- Tony Tremblay

- AP Photo/Michael Dwyer

**Notes:**
Caption: Energy-related carbon dioxide emissions in the Northeast, compared with the major carbon-emitting nations of the world. U.S. emissions include the Northeast.

Reducing Emissions in the Northeast
Reducing emissions in the Northeast alone will not stem global warming; nevertheless, the region can play a significant role in responding to this global challenge. Taken together, the Northeast’s nine states ranked as the world’s seventh highest emitter of CO2 compared with entire nations in 2001, just behind India and Germany and ahead of Canada.

However, the Northeast is also a financial and intellectual powerhouse, a world leader in science and technology, and a historic innovator in public policy. Even with its growing economy and population, the region has managed to slow its growth in energy-related CO2 emissions to just 0.3 percent per year since 1990—well below the national average of 1 percent per year—through a combination of past energy and transportation policies, expansion of less energy-intensive industries such as biotechnology, and other factors.

Today, the Northeast is well positioned to help lead the national and international actions needed to ensure a healthy future climate for our children and grandchildren—and to reap the economic benefits of leading-edge entrepreneurship. Recent examples of the region’s leadership and innovation in reducing heat-trapping emissions include:
The Regional Greenhouse Gas Initiative (RGGI), the first U.S. multi-state cap on carbon emissions, which will require the electric-power sector to decrease its emissions 10 percent below current levels by 2019.
Many state-level actions (including policies to promote energy efficiency and renewable energy, clean cars, and climate action plans) and efforts to reduce emissions from state government activities.
Emissions-reduction strategies being implemented by many municipalities, corporations, and universities.

## Further warming depends on our emissions choices

- Source: IPCC 2001

- HIGHER
**A1FI**

- LOWER
**B1**

- Further warming depends on our emissions choices

## Projecting future climate change for the Northeast	

- Obtain scenarios of future emissions from human activities
- Use scenarios as input to global climate model simulations
- Downscale global-scale projections to the regional level

- (b)

## Slide 11

**Notes:**
Caption: Observed and model-based changes in annual average temperature for the Northeast (in oF) relative to 1961-1990 average temperature. Modeled historic and future temperatures represent the average of the GFDL, HadCM3, and PCM models.

Temperature. Average temperatures across the Northeast have risen more than 1.5 degrees Fahrenheit (°F) since 1970, with winters warming most rapidly—4°F between 1970 and 2000. If higher emissions prevail, seasonal average temperatures across the state are projected to rise 8°F to 12°F above historic levels in winter and 6°F to 14°F in summer by late-century, while lower emissions would cause roughly half this warming. Under the higher-emissions scenario New York’s cities can expect a dramatic increase in the number of days over both 90°F and 100°F (see the section on health impacts).

## Summer Heat Index:

- How hot will an average summer day “feel”?

**Notes:**
Changes in average summer heat index—a measure of how hot it actually feels, given temperature and humidity—could strongly aff ect quality of life in the future for residents of the Northeast. Red arrows track what summers could feel like in, for example, the NYC Tri-State region (the greater New York City metropolitan region, encompassing parts of New Jersey and Connecticut) over the course of the century under the higher-emissions scenario. Yellow arrows track what summers in these states would feel like under a lower-emissions scenario.

## Heat-Waves and Temperature Extremes

- AP Photo/Michael Dwyer

**Notes:**
Caption: The number of days over 90°F in large northeastern cities is projected to increase in the coming decades until, by late-century, some cities could experience nearly an entire summer of such days under the higher-emissions scenario. Projections under this scenario also show a dramatic increase in the currently small number of days over 100°F (as depicted in the inset boxes).

When we think of weather-related injuries and deaths, tornadoes and hurricanes most often come to mind as the primary culprits, rather than hot, sticky summer days. Yet in six out of 10 recent years (between 1993 and 2003) heat was the leading weather-related killer in the United States. From 1999 to 2003 the nation reported 3,442 heat-related deaths, two-thirds of which were directly caused by exposure to extreme heat (heat was a contributing factor in the other third).3 In 1995 a five-day heat wave in Chicago generated maximum temperatures ranging from 93°F to 104°F and caused an estimated 700 deaths.  This event was an unwelcome preview of the temperature extremes and public-health challenges that are expected to intensify with global warming. 

Heat waves are most dangerous in urban areas because of the large concentration of potentially vulnerable people (see the text box on social vulnerability and cities) and the so-called urban heat-island effect, which drives both day and nighttime temperatures higher in cities than in suburbs and rural areas. The effect occurs mainly because pavement and buildings absorb and retain the sun’s energy more effectively than fields and forests.

## Increasing winter precipitation

**Notes:**
Winter precipitation (in the form of both snow and rain falling in winter months) has been increasing over the past few decades, and is projected to continue increasing, with slightly larger changes under the higher-emissions scenario than the lower-emissions scenario.
Little change is expected in summer rainfall, although projections are highly variable.

On average, precipitation in the Northeast is relatively consistent throughout the year, although it can vary greatly from year to year and month to month. The recent historical precipitation pattern in the Northeast was dominated by an extended drought in the early 1960s, which lasted for several years [Figure 6].  This drought was the worst to occur in the NE region since the beginning of record keeping in the late 19th century, and possibly since European settlement.[i],[ii] 
Excluding this event, there has been a gradual increase of about 5 to 10 percent in annual average precipitation across the Northeast since 1900.2,[iii] Most of that increase is evenly split between spring, summer, and fall, with little change in winter precipitation. Over the past few decades, however, this trend has reversed. Average annual precipitation shows a slight decrease, but winter precipitation has begun to increase at a rate of up to 0.15 inch per decade. 
The most significant trend has been in the type of precipitation that falls. As winter temperatures rise, more precipitation is falling as rain and less as snow.
In the future, most model simulations suggest a steady increase in annual precipitation, with a total increase of 10 percent (or about four inches per year) by the end of the century. Unlike temperature, the magnitude of annual precipitation changes is not projected to differ significantly under the higher- and lower-emissions scenarios. 
Winter precipitation, however, is projected to increase more under the higher-emissions scenario than the lower-emissions scenario (Figure 6). By mid-century, winter precipitation could increase between 11 percent (lower emissions) and 16 percent (higher emissions) on average. By the end of the century, winter precipitation could increase an average of 20 to 30 percent, with greater increases under the higher-emissions scenario. And compared with the past few decades, a greater proportion would be expected to fall as rain rather than as snow. Overall, little change in precipitation is projected in summer months, although individual models project both increases and decreases, in part due to the high variability in year-to-year rainfall. 

## Declining Snow Cover

**Notes:**
Caption: If higher emissions prevail, a typical snow season may become increasingly rare in much of the Northeast toward the end of the century. The red line in the map captures the area of the northeastern United States that, historically, has had at least a dusting of snow on the ground for at least 30 days in the average year. The white area shows the projected retreat of this snow cover by late-century to higher altitudes and latitudes, suggesting a significant change in the character of a Northeast winter.

Projected Climate Change: Winter Snow
Snow is an iconic characteristic of winter in the Northeast and is part and parcel of many revered winter activities and traditions. But rising temperatures over the past few decades have already produced some noticeable changes in the region’s snow. For example, the “slushiness” of snow—its wetness or density—has increased while the number of snow-covered days has decreased.

The number of snow-covered days per winter month in the Northeast ranges, on average, from close to zero in southern Pennsylvania to 30 in parts of Maine, New Hampshire, northern New York, and Vermont. As temperatures rise, snow is projected to appear later in the winter and disappear earlier in the spring, shortening the overall snow season. By late-century:
Most of the Northeast is projected to lose 10 to 15 snow-covered days per winter month under the higher-emissions scenario and four to eight such days under the lower-emissions scenario. The largest decreases may occur across the central part of the region, where the threshold between snow and no snow is most sensitive.
The northern part of the region, currently snow-covered for almost the entire winter season, is projected to lose up to half of its snow-covered days under the higher-emissions scenario, or more than one-quarter under the lower-emissions scenario.
The southern and western parts of the Northeast could experience as few as 5 to 10 snow-covered days in winter, compared with 10 to 45 days historically. 
The impacts of a declining snowpack and increase in winter rain on industries such as skiing and snowmobiling are addressed in the winter recreation chapter of this assessment; impacts on seasonal stream flow and water supplies are addressed in the text box on water resources.

## Extreme Precipitation

- Heavy rainfall events are becoming more frequent across the Northeast
- Under both emissions scenarios
- rainfall is expected to become more intense
- periods of heavy rainfall are expected to become more frequent

- Associated Press

**Notes:**
The frequency of heavy rainfall events is increasing across the Northeast.
Under both emissions scenarios, rainfall is expected to become more intense. In addition, periods of heavy rainfall are expected to become more frequent. 
Some East Coast winter storms are projected to shift from earlier to later in the winter season as temperatures rise, and more storms are expected to travel further up the coast and affect the Northeast.

Extreme precipitation can inflict tremendous damage on homes, businesses, public infrastructure and ecosystems, as well as disrupting economic activity and daily lives. In the fall of 2005 and spring of 2006, the Northeast was hard hit by several extreme precipitation events that resulted in loss of life and an estimated $130 million dollars in property damage.   
During the 1980’s and 1990’s, the Northeast experienced a rise in heavy precipitation events, defined as more than two inches of rain falling in less than 48 hours9. To assess possible future changes in extreme events, we use the following three measures:
The average intensity of precipitation, calculated as the number of days that it rains each year, divided by total annual rainfall
The number of heavy precipitation events, defined as more than two inches of rain in less than 48 hours
The intensity of once-a-year extreme precipitation events, calculated as the amount of precipitation that falls over five consecutive days in a given year
All three measures of extreme precipitation are expected to increase over the coming century. For precipitation intensity, or the average amount of rain that falls on any given rainy day in the Northeast, increases of 8 or 9 percent are projected by mid-century, and increases of 10 to 15 percent by the end of the century. In other words, wet days will become wetter. 

The number of heavy precipitation events is also projected to increase by 8 percent by mid-century, and 12 to 13 percent by the end of the century. This means that, in addition to having more rain when it does rain, there will also be more two-day periods with heavy downpours. Finally, increases are also projected for the wettest five-day period of each year. By mid-century, 10 percent more rain is projected to fall during these events. By the end of the century, 20 percent more rain is projected relative to the average event during 1961 to 1990. Overall, these changes indicate that the types of heavy rainfall events and floods that have occurred in the Northeast in recent years will become increasingly common.

## Changing Northeast Hydrology 

**Lower emissions**

**Higher emissions**

**(2070-2099)**

**(2070-2099)**

- USGS/David Armstrong

- Nancy Brammer

- More water
- when we don’t need it.

- Less water
- when we do.

**Notes:**
Caption (flooding): River Flooding Affects Water Quality. Heavy rainfall in 2004 turned the waters of the Susquehanna in Pennsylvania into a torrent, damaging many properties and negatively affecting water quality. Under either emissions scenario, extreme precipitation is projected to increase, potentially creating more frequent river flooding.

Caption (low stream flow): Communities and Wildlife Depend on Adequate Stream Flow. Conditions of low stream flow are projected to last roughly a month longer by late-century under the higher-emissions scenario, with little change under the lower-emissions scenario. For communities dependent on streams and rivers for their water supply, this trend is cause for concern

Changes in the surface water balance are reflected in evaporation, soil moisture, and runoff: How much water is entering the system (precipitation)? How much is leaving (through evaporation and runoff)? How much remains (as measured by soil moisture)? To examine the potential impacts of climate change on surface or terrestrial hydrology in the Northeast, we rely on simulations from the Variable Infiltration Capacity hydrological model, driven by historical observed temperature and precipitation and by future projections of changes in temperature and precipitation likely to occur under the higher and lower emissions scenarios.  
Climate change is projected to bring increases in winter precipitation and warmer temperatures, with little change in summer rainfall. Increasing winter precipitation would mean more water available for runoff and evaporation. As temperatures warm, snow will also melt faster and earlier. For this reason, runoff and soil moisture in winter and early spring is likely to increase. These increases could be followed by reductions in soil moisture in the late summer and early fall, and possible water shortages. Late summer and early fall reductions in soil moisture could arise because warmer temperatures drive higher evaporation rates, which would not be compensated for by additional rainfall. Projected winter and spring increases, and summer and fall decreases, are generally greater under the higher scenario as compared with the lower scenario, highlighting the important influence of temperature on hydrology and surface water in the Northeast.  
These trends in soil moisture, evaporation, and other aspects of hydrology will have important implications for the availability of water for agriculture and other uses in the Northeast. Moreover, extreme events such as droughts that can occur on top of these long-term trends have even greater potential for creating economic and ecosystem damage. A drought is defined here as occurring when monthly soil moisture is more than 10% below the long-term mean (relative to historical simulations). This definition relates directly to the availability of water for agriculture and water supply. Drought events are classified as being short (1-3 months), medium (3-6 months) or long-term (6+ months).  
Historically, short-term droughts occur one out of every two years over most of the Northeast and once in every three years over inland New York State, western Pennsylvania and northern Maine [Figure 9]. Medium-term droughts are far less common; historically, they occurred anywhere from once every fifteen years for the inland regions listed above, to not at all for some coastal areas. Long-term droughts occurred on average less than once in thirty years[i]. 54 Note that these simulations do not include the 1960s drought, since they are not based on observed temperature and precipitation. Historical drought estimates were generated using the Variable Infiltration Capacity (VIC) model, driven by historical climate model simulations, as discussed in section 2.

## Increasing Summer Drought

**Hotter summers increase evaporation rates and reduce soil moisture**
**With higher emissions, project annual short-term droughts across much of the Northeast by end-of-century.**

**Lower emissions**

**Higher emissions**

**(2070-2099)**

**(2070-2099)**

**(1961-1990)**

- Short-term drought (1-3 months)

**Notes:**
Changes in the surface water balance are reflected in evaporation, soil moisture, and runoff: How much water is entering the system (precipitation)? How much is leaving (through evaporation and runoff)? How much remains (as measured by soil moisture)? To examine the potential impacts of climate change on surface or terrestrial hydrology in the Northeast, we rely on simulations from the Variable Infiltration Capacity hydrological model, driven by historical observed temperature and precipitation and by future projections of changes in temperature and precipitation likely to occur under the higher and lower emissions scenarios.  
Climate change is projected to bring increases in winter precipitation and warmer temperatures, with little change in summer rainfall. Increasing winter precipitation would mean more water available for runoff and evaporation. As temperatures warm, snow will also melt faster and earlier. For this reason, runoff and soil moisture in winter and early spring is likely to increase. These increases could be followed by reductions in soil moisture in the late summer and early fall, and possible water shortages. Late summer and early fall reductions in soil moisture could arise because warmer temperatures drive higher evaporation rates, which would not be compensated for by additional rainfall. Projected winter and spring increases, and summer and fall decreases, are generally greater under the higher scenario as compared with the lower scenario, highlighting the important influence of temperature on hydrology and surface water in the Northeast.  
These trends in soil moisture, evaporation, and other aspects of hydrology will have important implications for the availability of water for agriculture and other uses in the Northeast. Moreover, extreme events such as droughts that can occur on top of these long-term trends have even greater potential for creating economic and ecosystem damage. A drought is defined here as occurring when monthly soil moisture is more than 10% below the long-term mean (relative to historical simulations). This definition relates directly to the availability of water for agriculture and water supply. Drought events are classified as being short (1-3 months), medium (3-6 months) or long-term (6+ months).  
Historically, short-term droughts occur one out of every two years over most of the Northeast and once in every three years over inland New York State, western Pennsylvania and northern Maine [Figure 9]. Medium-term droughts are far less common; historically, they occurred anywhere from once every fifteen years for the inland regions listed above, to not at all for some coastal areas. Long-term droughts occurred on average less than once in thirty years[i]. 54 Note that these simulations do not include the 1960s drought, since they are not based on observed temperature and precipitation. Historical drought estimates were generated using the Variable Infiltration Capacity (VIC) model, driven by historical climate model simulations, as discussed in section 2.

## Changes in Suitable Climate Conditions 

**Changes in Suitable Climate Conditions **
**For Different Forest Types **
**by Late-Century**

- Jerry and Marcy Monkman

**Notes:**
Caption (figure): Much of the Northeast is currently dominated by hardwood forests composed of maple, beech, and birch; higher altitudes and latitudes are dominated by spruce/fir forests. As the climate changes this century, suitable habitat for spruce and fir species is expected to contract dramatically under either emissions scenario (compared with observed forest distribution in the 1990s, shown here as “current”). Suitable maple/beech/birch habitat is projected with move significantly northward under the higher-emissions scenario, but shift far less under the lower-emissions scenario. (The “other” category includes species such as red, white, and jack pine.)

Caption (logging truck): A Treasured but Threatened Resource. Residents and tourists alike value the Northeast’s forests (such as this mix of hardwoods and conifers in northern Vermont) for timber and firewood, scenery and solitude, and recreational activities such as hunting, fishing, skiing, snowmobiling, hiking, canoeing, and bird-watching.

Projected changes in Northeast forests
NECIA researchers modeled potential shifts in the distribution of habitat suitable for 134 tree species throughout the Northeast (based on their current climatic range) under both the lower- and higher-emissions scenarios. Another NECIA analysis examined the potential impact of rising temperatures and atmospheric CO2 (individually and combined) on productivity (growth), net carbon uptake, nitrogen cycling, and water yield in five forest research sites across the region. A third analysis modeled changes in the expanding range of a forest insect pest, the hemlock woolly adelgid. Finally, another study analyzed the way in which the distribution of birds might change as forest habitat shifts over time and habitat quality declines. 

Habitat suitable for most of the region’s tree species is projected to move northeast as the climate continues to warm. The maximum range shift is projected to be about 500 miles in response to the climate changes expected this century under the higher-emissions scenario; the maximum range shift would be about 350 miles if lower emissions prevail. While trees can persist in areas where the climate is no longer well suited to their requirements, they may become less productive and more vulnerable to competition and other stresses, ultimately risking displacement by better-suited species.

Spruce/Fir Forests
The most vulnerable of the Northeast’s forests are the vast cool-climate communities dominated by conifers such as red spruce and balsam fir. Suitable habitat for the group of species that make up spruce/fir forests is projected to diminish substantially with global warming under either emissions scenario. All areas of the Northeast now dominated by spruce/fir forests are projected to become less suitable for this group of tree species, and better suited to others. As this happens, habitat for different species of spruce and fir trees is projected to change at different rates, but these rates are consistently greater under the higher-emissions scenario.

Wildlife habitat
The spruce/fir forests of the Northeast are home to species such as the snowshoe hare, American marten, and endangered Canada lynx that are already living at the southern edge of their range. Thus, these species are vulnerable to any further loss of habitat in the U.S. portion of their range.

High-elevation forest
High-elevation spruce/fir forests, confined to the Northeast’s mountains, cover just 1 percent of the region’s landscape today. These forests are currently restricted to specific climate conditions and are likely to see a decline in range as the climate changes. Only under the lower-emissions scenario is habitat suitable for these high-elevation forests likely to remain into the next century, though the long-lived nature of trees could enable patches of spruce/fir to persist for some time under either scenario. These forests, in turn, provide unique habitat for a number of threatened bird species. 

Industry
Dramatic declines in spruce/fir forests projected under the higher-emissions scenario would greatly exacerbate stresses on the Northeast’s economically important pulp and paper industry, particularly in Maine. Winter warming, in addition to its direct role in redefining tree habitat, interferes with traditional timber harvesting practices in the region, which typically take advantage of the cold winter months when soils are frozen, minimizing the soil damage that could be caused by the heavy equipment used for cutting trees. As winters continue to warm over the coming century, forest soils will remain frozen for shorter periods, freeze less deeply, or potentially not freeze at all in more southerly areas.

## For Gardeners, Landscapers and Farmers . . . 

**For Gardeners, Landscapers and Farmers . . . **

- Climate change will bring new opportunities

- And new risks and costs

**Notes:**
For Gardeners and Farmers . . . 
Climate change might allow exploration of new plant species and new markets,
but will also bring with it increased weed, disease, and insect pressure, 
damaging summer heat stress, and new challenges for water management

## Many fruit crops require cold winter.

- AP Photo/Steven Senne

**Notes:**
Caption: Cranberry Harvests at Risk as Temperatures Rise. Massachusetts and New Jersey are among the top national producers of cranberries, supplying nearly half of the U.S. crop. By mid-century under the higher-emissions scenario, it is unlikely that these areas will provide cranberries with the long winter-chill periods required for optimum flowering, fruit set, and seed development. New Jersey is particularly vulnerable under either scenario. Unlike other fruits, no known low-chill variety of cranberry exists.

Warmer winter temperatures will have a profound effect on the region’s plant life and agricultural crops, particularly for the many varieties that require a prolonged period of winter chill and dormancy for optimum flowering, fruit set, and seed development. Important examples include apples, blueberries, grapes, and cranberries, as well as winter wheat.

Chilling requirements (often approximated by calculating the cumulative hours below roughly 45°F) vary considerably between species and even among varieties of a single species. 

The NECIA study projected the percentage of years in various time periods this century when winter temperatures in the Northeast would not be sufficiently cold to meet chilling requirements of 400, 1,000, and 1,800 cumulative hours below 45°F. The analysis focused on identifying those areas where chilling requirements would not be met in at least 20 percent of the projected winters—an indicator of significant risk to sustained crop production.

The 1,000-hour chilling requirement affects fruits such as northern blueberry varieties, summer-bearing raspberries, and a number of apple varieties, including McIntosh, Empire, and Granny Smith. In 2005 most of New Jersey’s $55 million blueberry crop was produced from a small set of cultivars, all of which require between 800 and 1,000 chilling hours. One thousand hours also represents the low end of chilling-requirement estimates for cranberries (which are thought to require 1,200 to 1,400 hours).
By mid-century the 1,000-hour chilling requirement would not be met in parts of Pennsylvania and much of New Jersey, Long Island, and southeastern Massachusetts (a key area of cranberry production) under the higher-emissions scenario.
If lower emissions prevail only southern New Jersey would fail to meet this chilling requirement.
By late-century this chilling requirement would not be met in New Jersey, much of Pennsylvania, and southern New England under the higher-emissions scenario.
Under the lower-emissions scenario, most of the region is expected to continue to satisfy this chilling requirement through the end of the century. New Jersey and parts of Pennsylvania, however, would fail to meet this requirement, and southeastern Massachusetts would become increasingly at risk of failing.

Growers of raspberries and blueberries could potentially adapt to warmer winters by switching to varieties with lower chilling requirements, which were originally developed for production in southern and western states. For long-lived orchard crops such as apples, and varieties with no known substitute such as cranberries, options are currently far more limited.

**                   **

## Slide 23

**Notes:**
Caption: The top image shows the location of Atlantic City, NJ, on Absecon Island. The light blue area in the bottom image depicts today’s FEMA 100-year flood zone (which extends beyond the area shown). Currently, this area has a 1 percent chance of being flooded in a given year. By 2100, this area is projected to flood, on average, once every year or two under either emissions scenario, inundating high tourist-value hotels and casinos. Under the higher-emissions scenario, the new 100-year flood height would be roughly four feet greater in 2100 than today, flooding a far greater area than the current FEMA flood zone.

To anticipate the potential frequency and extent of damage from future coastal floods, researchers use a benchmark called the “100-year flood” that allows them to ask how frequently a flood of similar magnitude may occur in the future as sea levels—and thus the baseline for flooding—rise. (See the text box on 100-year floods.) It also allows researchers to ask what the future flood level of a storm surge with the same probability of occurrence (1 percent per year) may be. It is important to note that the 100-year flood represents a historical average, and severe flooding associated with storm surges has occurred in the Northeast in intervals much shorter than 100 years.23

A NECIA analysis identified the average return time between major coastal flooding events (e.g., the 100-year flood) and combined the results with different scenarios of future sea-level rise to generate projections of future coastal floods.24 Five coastal sites in the Northeast were examined: Atlantic City, NJ; Boston; New London, CT; New York City; and Woods Hole, MA. Researchers projected both the change in recurrence intervals of today’s 100-year coastal flood in those locations, as well as the floodwater heights associated with future 100-year floods, based on projections of sea-level rise by mid- and late-century.25 The results outlined below focus only on the IPCC’s most recent and relatively conservative projections for both the lower- and higher-emissions scenarios. Because of the time lag between atmospheric warming and global sea-level rise outlined above, these results, while dramatic, show relatively subtle differences between the two emissions scenarios in the first half of the century.

The 100-Year Flood

Historical records of extreme events allow us to calculate the approximate intervals at which floods of a certain height have occurred in the past and to estimate the frequency at which they may recur in the future. A frequently used benchmark is the “100-year flood”—the maximum flood elevation likely to be equaled or exceeded on average once every century in a given location. In any one year, there is a 1 percent probability that a 100-year flood will occur. Similarly, a 10-year flood has a 10 percent probability of occurring in any given year, and a 1,000-year flood has a 0.1 percent probability. It is important to note that these are not predictions, but rather statements of probabilities based on historical averages.

The expected elevation of a 100-year flood at a given location is commonly used in emergency planning and on flood-risk maps to show areas vulnerable to storm related flooding of that magnitude. The 100-year flood elevation is also a standard used to determine the need for flood insurance or “flood-proofing” requirements attached to building permits, and the applicability of other environmental regulations and protective measures. In this sense, the 100-year flood is one way of capturing society’s threshold for risk—areas exposed to this level of risk require greater precautionary measures to prevent As sea level rises, extensive damage than those with a lower exposure.

## Atlantic City: Today’s 100-Year Flood

- Google, Sanborn Map Company, Inc.,
- State of New Jersey, TerraMetrics

**Notes:**
Caption: The top image shows the location of Atlantic City, NJ, on Absecon Island. The light blue area in the bottom image depicts today’s FEMA 100-year flood zone (which extends beyond the area shown). Currently, this area has a 1 percent chance of being flooded in a given year. By 2100, this area is projected to flood, on average, once every year or two under either emissions scenario, inundating high tourist-value hotels and casinos. Under the higher-emissions scenario, the new 100-year flood height would be roughly four feet greater in 2100 than today, flooding a far greater area than the current FEMA flood zone.

To anticipate the potential frequency and extent of damage from future coastal floods, researchers use a benchmark called the “100-year flood” that allows them to ask how frequently a flood of similar magnitude may occur in the future as sea levels—and thus the baseline for flooding—rise. (See the text box on 100-year floods.) It also allows researchers to ask what the future flood level of a storm surge with the same probability of occurrence (1 percent per year) may be. It is important to note that the 100-year flood represents a historical average, and severe flooding associated with storm surges has occurred in the Northeast in intervals much shorter than 100 years.23

A NECIA analysis identified the average return time between major coastal flooding events (e.g., the 100-year flood) and combined the results with different scenarios of future sea-level rise to generate projections of future coastal floods.24 Five coastal sites in the Northeast were examined: Atlantic City, NJ; Boston; New London, CT; New York City; and Woods Hole, MA. Researchers projected both the change in recurrence intervals of today’s 100-year coastal flood in those locations, as well as the floodwater heights associated with future 100-year floods, based on projections of sea-level rise by mid- and late-century.25 The results outlined below focus only on the IPCC’s most recent and relatively conservative projections for both the lower- and higher-emissions scenarios. Because of the time lag between atmospheric warming and global sea-level rise outlined above, these results, while dramatic, show relatively subtle differences between the two emissions scenarios in the first half of the century.

The 100-Year Flood

Historical records of extreme events allow us to calculate the approximate intervals at which floods of a certain height have occurred in the past and to estimate the frequency at which they may recur in the future. A frequently used benchmark is the “100-year flood”—the maximum flood elevation likely to be equaled or exceeded on average once every century in a given location. In any one year, there is a 1 percent probability that a 100-year flood will occur. Similarly, a 10-year flood has a 10 percent probability of occurring in any given year, and a 1,000-year flood has a 0.1 percent probability. It is important to note that these are not predictions, but rather statements of probabilities based on historical averages.

The expected elevation of a 100-year flood at a given location is commonly used in emergency planning and on flood-risk maps to show areas vulnerable to storm related flooding of that magnitude. The 100-year flood elevation is also a standard used to determine the need for flood insurance or “flood-proofing” requirements attached to building permits, and the applicability of other environmental regulations and protective measures. In this sense, the 100-year flood is one way of capturing society’s threshold for risk—areas exposed to this level of risk require greater precautionary measures to prevent As sea level rises, extensive damage than those with a lower exposure.

## Boston: The Future 100-Year Flood Zone Under the Higher-Emissions Scenario

**Notes:**
Caption: This image shows the current Federal Emergency Management Agency (FEMA ) 100-year flood zone (hatched darker blue) as well as the extent of the projected 100-year flood zone in 2100 (lighter blue) under the higher-emissions scenario for the waterfront/Government Center area of Boston. Important Boston landmarks (such as Faneuil Hall) and transportation infrastructure currently not at great risk of flooding could witness repeated flooding in the future unless protected from such events. Flood elevations under the lower-emissions scenario are roughly half a foot lower than the flooding depicted here (but still 1.5  feet higher than the current 100-year flood).

ADDITIONAL INFORMATION PHK CHECK ! 
Coastal Flooding
By mid-century substantial changes in coastal flooding are already evident.
Substantial increases in the maximum elevation of major coastal floods are projected for all five locations, but particularly Boston and Atlantic City.
Substantial increases in the frequency of today’s 100-year floods are expected at all five locations:
Every two to three years in Boston on average (under the higher- and lower-emissions scenarios, respectively)

By 2100, the significance of emissions choices for sea-level rise and coastal flooding become more apparent as both the maximum heights and recurrence intervals of coastal floods increase, particularly under the higher-emissions scenario.
Most locations are projected to experience increases over the current 100-year-flood elevation of roughly 2.5 feet under the higher-emissions scenario and roughly two feet under the lower-emissions scenario.
Today’s 100-year coastal floods are projected to recur much more often. On average:
Under the higher-emissions scenario, every year or two in Boston 
Under the lower-emissions scenario, every year or two in Boston

These projections are based on changes in sea-level rise alone and do not include other potential changes such as shifts in shoreline position or changes in storm frequency, intensity, or track. If storms strike the Northeast’s coast with greater frequency and intensity, for instance, the frequency of coastal floods (and associated damages) would be expected to rise even more. 

## Meeting the Climate Challenge

- We must adapt to unavoidable change set in motion by past emissions.

- Jupiter Images

- AP Photo/Michael Dwyer

- Andrew F. Kazmierski

**Notes:**
Caption (irrigation): The frequency of droughts is projected to increase over the coming decades under the higher-emissions scenario, with little change projected under the lower-emissions scenario. Drought and hot summer conditions would increase irrigation needs, particularly for growers of traditionally rain-fed crops (common in the Northeast). Farmers may be able to cope by investing in and upgrading irrigation systems, assuming the up-front and long-term operational costs are within reach.

Caption (fishing): Warming waters are projected to change the Northeast fishing industry, placing added pressure on both fish stocks and those who fish for a living. As the Northeast climate changes and certain mainstays of the fishing industry (such as lobster) are pushed northward or into deeper waters, some fishermen and women may be able to switch to harvesting different species, provided investments in new fishing equipment are affordable.

## There are limits to adaptation

## Meeting the Climate Challenge

- But the extent of further change depends greatly on emissions choices we make today.

## Reducing  

- New Jersey’s Emissions

- Community Energy, Inc.

## For more information

- About the NECIA www.climatechoices.org/ne
- About UCS
-    www.ucsusa.org

## Projected Rise in GlobalSea Level Relative to 2005

**Notes:**
Caption: This graph depicts the average or mid-range of a number of different sea-level rise (SLR) simulations: a continuation of recent observed SLR rates (green line), the mid-range of the most recent IPCC projections under the lower-emissions scenario (yellow line), the mid-range of the recent IPCC projections under the higher-emissions scenario (red line), and the midrange of a more recent set of projections under the higher-emissions scenario (blue line).

Projected Climate Change: Ocean temperatures and sea-level rise
Regional sea-surface temperatures have increased 1oF since 1900 and are projected to continue increasing, though at a slightly slower rate than regional air temperatures. By the end of the century, regional sea-surface temperatures are projected to rise an additional 6°F to 8°F under the higher-emissions scenario and 4°F to 5°F under the lower-emissions scenario. These warmer temperatures may adversely affect native marine species in the Northeast, including the commercially important fisheries whose southernmost range is limited by warm temperatures.

Globally, sea levels have been rising since the end of the last ice age and are rising even faster now. This acceleration is caused by two different mechanisms related to increasing temperatures: thermal expansion of seawater as it warms and increasing inflow of water from melting ice sheets and glaciers.

Assuming no further warming, a continuation of the recent historical rate of global sea-level rise could lead to a nearly six-inch increase over 2005 levels by the end of the century. Factoring in further global warming, however, the IPCC projects that global sea levels will rise between 7 and 14 inches under the lower-emissions scenario and between 10 and 23 inches under the higher-emissions scenario.

A more recent analysis, however, has projected much greater end-of-century sea-level rise: on the order of 2 to 4.5 feet above 2005 levels under the higher-emissions scenario. Even these projections may be conservative in that they do not account for the rapid rate of ice breakup and melting currently being observed in the polar ice sheets (particularly those of Greenland), nor do they assess the potential for further acceleration of this melting.

## NYC: Today’s 100-Year Flood

**Notes:**
Caption: The light blue area in these maps depicts today’s FEMA 100-year flood zone for New York City (i.e., the area of the city that is expected to be flooded once every 100 years). With additional sea-level rise by 2100 under the higher-emissions scenario, this area is projected to have a 10 percent chance of flooding in any given year; under the lower-emissions scenario, a 5 percent chance. As the close-up shows, critical transportation infrastructure located in the Battery could be flooded far more frequently unless protected. The 100-year flood at the end of the century (not mapped here) is projected to inundate a far larger area of New York City, especially under the higher-emissions scenario.

Coastal Flooding
New York City, by far the region’s largest urban center, provides an important example. Its Metropolitan Transit Authority subways, buses, and railroads move nearly 6 million people on an average workday, and 250 million vehicles pass through its tunnels and bridges each year. The small waterfront area known as the Battery, at the southern tip of Manhattan, provides a prime example of the city’s vulnerability to coastal storms. The Battery is home to such critical transportation infrastructure as F.D.R. Drive, West Street, the West Side Highway, the Port Authority Trans-Hudson (PATH) tunnels linking Manhattan and New Jersey by train, and the Brooklyn-Battery auto tunnel entrance. While concrete bulkheads and a seawall protect much of the Battery, it is considered highly vulnerable to coastal flooding and has been inundated during past storms.36,37 Flooding on F.D.R. Drive and in other parts of the city during a1992 nor’easter, for instance, brought Manhattan’s metropolitan transportation system to a near-shutdown. This same storm pushed the high-water level nearly eight feet above the current mean sea level, coming within one to two feet of the critical level that would have flooded the subway and rail tunnels. In 2050, the maximum elevation of New York City’s 100-year flood is projected to reach 9.5 feet under either emissions scenario, and by 2100, more than 10.5 feet under the higher-emissions scenario. Thus, by the end of the century, major coastal flooding projected by the NECIA analysis threatens to disrupt the city’s transportation system with increasing frequency, while 100-year floods threaten to inundate far greater expanses of the city. In recognition of its vulnerability to coastal flooding, New York City is taking steps both to adapt to and reduce its heat-trapping emissions.

## Streamflow and Water Supply