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Season CreepHow Global Warming is Already Affecting the World Around Us.
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Acknowledgements
The author would like to thank all those who provided
comments, data or information for this paper, specifically:
Mark D. Schwartz, University of Wisconsin-Milwaukee;
Terry L. Root, Stanford University; Ellen Baum, Clean Air
Task Force; and the staff at Clear the Air and the National
Environmental Trust. In addition, the author would like
to acknowledge the work of the Pew Center on Global
Climate Change and the work that Camille Parmesan,
University of Texas-Austin and Hector Galbraith,
University of Colorado-Boulder did synthesizing the
observable impacts of climate change in the U.S.
This report was made possible with the funding from
The Pew Charitable Trusts. The opinions expressed in
this report are those of the author and do not necessarily
reflect the views of The Pew Charitable Trusts.
Jonathan Banks, Policy Director
Clear the Air
March 2006
Clear the Air is a national public education campaign to
combat global warming and improve air quality.
1200 18th Street, NW
Washington, DC 20036
202-887-1715
www.cleartheair.org
printer to strip union/recycled/soy inks bugs here
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Even though the full
impact of global
warming has yet to be
felt, the world around us
is already feeling the heat. According
to the latest scientific studies
reviewed for this paper, the planet
is warming and higher temperatures
are disrupting our very seasons and
turning their key indicators upside
down. Whats most startling about
the results of this range of studies
is that the researchers themselves
are tying the changes to warming
temperatures in essence, pointing
their fingers at global warming.
While to some, an early arrival
of spring may sound good, an
imbalance in the ecosystem can
wreak havoc. Natural processes
like flowers blooming, birds
nesting, insects emerging, and ice
melting are triggered in large part
by temperature. As temperatures
increase globally, the delicately
balanced system begins to fall into
ecological disarray. We call this
season creep.
In this summary we have analyzed
the most recent scientific evidence
of seasonal changes due to global
warming. Only peer-reviewed studies
published in scientific journals are
included. The results are clear: in the
Season CreepHow Global Warming is AlreadyAffecting the World Around Us
An Analysis of the Impact of
Climate Change on Seasonal Cycles
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United States and across the Northern
Hemisphere, hundreds of species
are changing in response to global
warming. Non-biological seasonal
shifts are occurring as well due to the
warming trend. In short, many of the
familiar signs and signals of spring
are arriving earlier due to global
warming:
Lilacs and honeysuckle are
blooming six days early;
Northern cardinals are singing 22
days early;
Canadian geese, robins and whip-
poor-wills are arriving earlier;
Columbine, forest phlox, butterfly
weed and shooting star are all
blooming earlier;
The breeding season of birds such
as the common murre and Mexican
jays is starting early;
Tree swallows are laying their eggs
nine days early;
Frogs are starting their mating
season 12 days early;
The marine food chain is being
disrupted as plankton bloomsarrive earlier;
Spring snow-melt in the Western
U.S. is happening 4 weeks earlier
than in the mid 20th century;
The growing season in the
upper latitudes of the Northern
Hemisphere is 12 days longer;
Lakes and rivers are freezing six
days later and thawing six days
earlier; and,
Warmer winters are moving the
maple syrup season earlier in the
year.
Canadian geese
are arriving
earlier;
Tree swallows
are laying
their eggs early
SEASON CREEP HOW GLOBAL WARMING IS ALREADY AFFECTING THE WORLD AROUND US
HONEYSUCKLE
TREE SWALLOW
CANADIAN GOOSE
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Why should we care? So what if
the ice melts sooner or the flowers
bloom early? Does it really matter?
It does. In school we were all
taught about the interconnectedness
of the natural world. Changes in
phenology (the relation between
climate and periodic biological
phenomena) in one species can
have dramatic impacts throughout
the ecosystem. For example, when
plants bloom earlier due to warmer
spring temperatures, insects that
rely upon them for food must adjust
their life cycles, as do other species
further up the food chain. If a
species in the chain does not adapt,
the chain is broken, and species begin
disappearing.
While most springtime events are
controlled by temperature, some
species time their spring events
based on hours of daylight, pushing
them out of sync with the rest of the
ecosystem that is following increased
temperature signals. Researchers in
Europe have begun studying long
distance migratory birds, specifically
the pied flycatcher. While spring
temperatures have increased in
the flycatchers nesting grounds in
Europe, the flycatchers arrival has
remained constant as it is governed
by length of day in its wintering
grounds in North Africa. This means
that the flycatcher is now arriving
too late from its wintering grounds in
Africa to take advantage of the peak
insect hatchings in Europe, which are
now earlier as a result of the warmer
temperatures at its nesting grounds.1
For many long distance migrants,
phenological changes could pose
grave risks and scientists are only
beginning to identify the dominoes
that could fall should climate change
continue unabated. And, as our
teachers taught us, we humans are inthat chain of dominoes.
As industrialized as we are,
there are still many ways that these
dominoes affect us already. Global
warming is proving disruptive to
cultural and economic activities
The Greenhouse Effect
Impacts of a Warming Arctic: Arctic Climate Impact Assessment ACIA, Overview report. Cambridge
University Press, 2004. http://amap.no/acia/
If a species in the
chain does not
adapt, the chain
is broken, and
species begin
disappearing.
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SEASON CREEP HOW GLOBAL WARMING IS ALREADY AFFECTING THE WORLD AROUND US
in a number of communities. For
instance, reductions in the length
and thickness of lake ice cover due
to the warming trend has had a clear
impact this winter many ice fishing
tournaments and winter festivals
have been affected or cancelled
due to insufficient ice. As a result,
traditions that have long been part
of a community s character are
suffering, and the economic benefits
of such events are being lost.
Global WarmingIt Is Here
Today. Human activities during the
last century particularly the burning
of fossil fuels have changed the
composition of the atmosphere in
ways that threaten to dramatically
alter the global climate in the years
to come. Global warming is caused
by the greenhouse effect, a natural
phenomenon in which gases in the
Earth s atmosphere, including water
vapor and carbon dioxide, trap
heat from the sun near the planets
surface. Without a natural greenhouse
effect, temperatures on Earth would
be too cold for life to survive.
Throughout the last century,
however, changes to the chemical
makeup of the Earth s atmosphere
have been accelerating. This is
largely as a result of humans
burning fossil fuels, which releases
large amounts of carbon dioxide
and other greenhouse gases
into the atmosphere. Since the
industrial revolution, atmospheric
concentrations of carbon dioxide
(CO2) have increased by 31 percent.2
Concentrations of other greenhouse
gases have increased as well. These
atmospheric changes have intensified
the greenhouse effect, allowing
less of the suns heat to escape the
Earth s atmosphere. Global average
temperatures increased during the
20th century by more than 1 F, with
Temperature and Greenhouse Gases
Impacts of a Warming Arctic: Arctic Climate Impact Assessment ACIA, Overview report. Cambridge
University Press, 2004. http://amap.no/acia/
Changes to
the makeup
of the Earths
atmosphere
have been
accelerating.
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While its true that the
Earths climate is
constantly changing,
the changes currently being felt are
at a pace that is faster than what
many species may be able to handle.
In a study published in February
in the journal Science, researchersconcluded that the warming in the
late 20th century in the northern
hemisphere is the greatest warming
the Earth has seen in 1,200 years.6
Species have always been forced
to adapt to changing climates, but
normally at a much slower pace.
Even when dramatic changes in
temperature have occurred, such as
during the past glacial cycles, species
tended to track the retreat or onset of the
glaciers instead of evolving to tolerate
new temperature regimes.7 During these
past glacial cycles, the environment was
not the one that exists today. Today,many species have nowhere to run.
Habitat destruction and fragmentation
have created ecological islands that
species may not be able to escape.8
Urban areas, highways and farm lands
surround our natural areas and block the
natural paths species would take to shift
their range in the face of climate change.
In addition, our ecosystems are under
stress from pollution, overexploitation,
and invasive exotic species.
Because of these stresses, at least 20 percent
of the worlds mammals, 12 percent of its
birds and 31 percent of its amphibians are
considered threatened with extinction.9 When
climate change is added onto these, the future
for many species is bleak. Recent research
has estimated that one-quarter of all species
will be on the road to extinction by 2050.10
Nowhere To RunA Changing Climate in a Fragmented World
the rate of change for the period
since 1976 roughly three times that
for the past 100 years as a whole.3
According to NASA, 2005 was the
hottest year in more than a century,
and the 1990s were the warmest
decade since measurements began
in 1861.4 If current trends continue,
temperatures could rise by an
additional 2.5 F to 10.4 F by 2100.5
Despite all of this, to many of
us global warming is a remote and
distant thing. We read in the papers
that polar ice caps are predicted to
melt in 2050 or 2100, but then we turn
to more immediate news. However,
scientific evidence is piling up daily,
showing that the first impacts of
global warming are already being
felt and that the rate of change is
occurring more rapidly than originally
expected. And yet, the impacts we are
seeing today may pale in comparison
to what we can expect, if global
warming continues unchecked. If
The 1990s werethe warmest
decade since
measurements
began in 1861.
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SEASON CREEP HOW GLOBAL WARMING IS ALREADY AFFECTING THE WORLD AROUND US
or more. Now however, phenology is
one of the primary tools for showing
the current impact of global warming
on our world. By analyzing the
careful historical records of scientists
and correlating them to temperature
records, modern day climatologists
are able to see alarming trends in
the natural cycles that govern our
seasons.
Earlier Signs of Spring
Spring indicies first leaf date departures by year across Northern Hemisphere, 1955-2002.
Schwartz 2006
For years
naturalists have
kept detailedrecords of
when the robins
arrived and
hundreds of
other naturalbeginnings.
between climate and periodic
biological and natural phenomena, is
a little known science that for much
of its history, was just a pastime of
nature lovers around the world. For
years naturalists have kept detailed
records of when the first buds on
poplars opened, when the daffodils
bloomed, when the robins arrived,
and hundreds of other natural
beginnings. In some cases the
records go back more than 100 years
all of these changes are happening in
response to just over a 1 F change
in temperatures, what kinds of
disruptions will we see in response to
the several degrees increase we expect
by this centurys end?
Phenologya 19th century
pastime gives us concrete
evidence of global warmings
fingerprint on our seasons.
Phenology, the study of the relation
ROBIN
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In recently published studies
scientists have shown
the definitive impact of a
changing climate on our
natural environment. These studies
add to the mountain of evidence that
global warming is here and the time
to address it is now.
Spring starting earlier due to
global warming: In a recent study
titled Fingerprints of Global
Warming on Wild Animals and
Plants, by Stanford University
scientist Terry Root and others,
researchers examined the springphenology of 130 species in the
Northern Hemisphere and found that
the first signs of spring are appearing
nearly 10 days earlier on average,
compared with 30 years ago. The
researchers overlaid temperature
data that shows the contribution of
human-caused global warming to
changes in plant and animal behavior.
Root says that this rapid global
environmental change is outpacing
species adaptation.11
Lilacs - the harbinger of an early
spring: Using models of the dates
of first leaf and first bloom in
lilacs and honeysuckle (species
which are good representatives of
the response of many temperate trees
and shrubs) driven by temperature
records for the Northern Hemisphere,
Mark D. Schwartz of the University
of Wisconsin-Milwaukee and his
colleagues have found that spring
is arriving between five and six
days earlier during the 1955-2002
period. This finding is consistent
with the warming trend reflected in
the temperature data and past smaller
scale studies. Schwartz found that
spring was warmer earlier, and that
the last freeze across the Northern
Hemisphere was also becoming
earlier at a similar rate.12
Nature changing its habits:
Another recent meta-analysisby Terry Root of 143 previously
published studies reveals a consistent
temperature-related shift, or
fingerprint, in a number of species,
everything from mollusks to mammals
and grasses to trees. More than 80
percent of the 1,400 plant and animal
species studied show a trend toward
earlier seasonal events. On average,
trees bud, frogs mate, and birds nest
more than a week earlier than they
did 50 years ago. One of the biggest
changes was in the breeding of the
Common Murre which has advanced
by 24 days per decade.13
How Climate Change is
Disrupting the Seasons
The dates of
first leaf and
first bloom of
lilacs show that
spring is arriving
5-6 days earlier.
LILACS
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SEASON CREEP HOW GLOBAL WARMING IS ALREADY AFFECTING THE WORLD AROUND US
The timing of
the spring maple
syrup tap season
is crucial and the
traditional tap
time has become
disrupted andhard to predict.
MAPLE SYRUP TAPPING
Leopold wouldnt recognize this
place: Aldo Leopold, the father
of wildlife ecology, helps provide
one of the longer term analyses of
species changes due to changing
temperatures. In the 1930s and 40s,
Leopold made detailed observations
of the timing of spring events on
his farm in Wisconsin. Recently,
researchers compared his data on
birds and native flowers to their
own surveys taken in the 1980s and1990s to see how species might
have changed during the 61-year
period in the face of a 5 F increase
in March temperatures. Researchers
found that Canadian geese arrive 29
days earlier, robins arrive 10 days
earlier, whip-poor-wills arrive 12
days earlier, northern cardinals sing
22 days earlier, columbine blooms 13
days earlier, forest phlox blooms 15
days earlier, butterfly weed blooms
18 days earlier and shooting star
blooms 10 days earlier. Of the 55
species studied, 35 percent showed
advancement of spring events. On
average, this study found that spring
events are occuring more than seven
days earlier now than they did during
Leopolds time.14
Maple syrup and a warmer
climateits not so sweet: A delicate
balance of sun, rain, snowfall, and
freezing temperatures is what helps
the maple tree turn its starch into the
sugar we in turn make into maple
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PhotoofMexicanjaybyBrianSmall.
The breeding
season of the
Mexican jay
advanced by an
average of 10
days. Egg laying
was also found tobe closely related
to spring monthly
temperatures.
MEXICAN JAY
syrup. A good maple syrup season
depends on nighttime temperatures
below freezing and warm daytime
temperatures greater than 40 F.
If there are a series of nights in
which temperatures dont fall below
freezing, the sap stops flowing. In
general, syrup tappers find that the
first sap flow of the season provides
the highest quality syrup, which
translates into the highest value
syrup.
The timing of the spring tap is
crucial and the traditional tap time
has become disrupted and hard to
predict. In Vermont, trees were
historically tapped between the
middle of March and the middle
of April. With warmer late winter
and early spring temperatures, this
has shifted towards the middle ofFebruary. The U.S. maple syrup
industry has significantly declined
since the early 1900s due to many
factors, including climate related
events such as severe weather and
insect outbreaks. Research is also
showing that actual sap production
may be decreased by warmer
winter and spring temperatures.
Furthermore, as climate modeling
efforts have shown, climate change
could, during the course of several
hundred years, remove the sugar
maple from the New England region
altogether. 15
Early breeding season:
Researchers studying Mexican jays
in the Chiricuahua Mountains of
southern Arizona found that between
1971 and 1998, the breeding season
of the birds advanced by an average
of 10 days. Egg laying was also
found to be closely related to spring
monthly temperatures, which have
increased during the duration of the
study by about 4.5 F.16 In a much
larger study of springtime bird habits,
researchers found that tree swallows
throughout their North American
range are laying their eggs nine days
early. The study looked more than
3,400 nest records that spanned the
years 1959-1991.17
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SEASON CREEP HOW GLOBAL WARMING IS ALREADY AFFECTING THE WORLD AROUND US
The study of phenology
provides us with a useful
tool for understanding the
current impacts of global warming on
our environment. However, to date,
phenological work is often limited in its
geographic coverage or it is restricted
to just a few species. Development of a
national network to provide coast to coast
phenological observations, long a dream of
scientists working on these issues, is finally
materializing. At an August 2005 meeting
in Arizona, scientists began the process
of implementing the first U.S.A. National
Phenology Network. The network, once
fully realized, will be instrumental in revealing
large-scale species response patterns to
climate change. The scientists have set
the goals for the network as (1) facilitating
thorough understanding of phenological
phenomena, including their causes and roles
in the biosphere; (2) providing empirical data
for ground-truthing, making the most of the
large public investment in satellite platforms
and remote sensing; (3) allowing the
detection and prediction of environmental
change for myriad applications, including
but not limited to assessing impacts of land
use and climate variability/change; and (4)
engaging thousands of citizen scientists
to contribute to data collection. The result
of these efforts will provide scientists with
a wealth of information to more accurately
characterize the phenological changes
occurring in the U.S. and compare them to
similar work being conducted throughout
the world. The network and materials from
the 2005 workshop can be accessed at:
www.npn.uwm.edu.
The National Phenology Network
Researchersdiscovered that
the food chain in
the North Atlantic
Ocean has been
radically altered.
COD
Marine environments are also
showing phenological changes:
Most of the research on phenological
changes has been conducted on
land, but researchers recently have
discovered that the food chain in
the North Atlantic Ocean has been
radically altered. Using records
of 66 different types of plankton,
the key to the marine food chain,
researchers tracked changes in peak
plankton bloom throughout a 44
year period. They discovered that
the timing of many plankton bloomshas been moving progressively
forward while others have stayed
stable. Researchers have found that
for the stable forms, length of day
is the likely driver for the timing of
their bloom. The study found that
due to the differences in how fast
each type of plankton is moving its
bloom date forward, a mismatch in
the food chain is occurring. This
is exacerbating the decline of such
commercial fish as cod. During the
study period, North Atlantic spring
sea surface temperatures increased by
almost 1.8 F. 18
Early amphibian breeding: In
one of the longest scientific records,
researchers studying frogs in Ithaca,
New York were able to compare
recent data from the 1990s to turn
of the century data. Researchers
found that temperatures in the area
have increased during the matingseason by 1.8-4 F and that male
frogs in almost 70 percent of the
species present at the studied lakes
were beginning their mating calls
approximately 12 days earlier than
they were in the early 1900s.19
Satellites show longer growing
season: Using satellite imagery
researchers have been able to
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Spring snowmelt
in the Western
U.S. is occurring
up to four weeks
earlier.
demonstrate that the growing
season in the higher latitudes of the
Northern Hemisphere (north of an
imaginary line between Portland,
ME and Portland, OR), has expanded
by approximately 12 days. The
lower latitudes have also shown an
increase in growing season, but not
as pronounced.20
Melting ice and snow: Spring
snow melt and lake ice-out (the
thawing of ice on the surface of a
body of water) dates are other spring
phenomena that are trending earlier
in the year. Researchers at the
Scripps Institution of Oceanography
have found that spring snow melt
in the Western U.S. is occurring up
to four weeks earlier than it was in
1948. While some of the changes are
attributed to other decadal weather
events, the researchers clearly state
that global warming is increasing
the trend toward earlier melt. The
implications for the water starved
West are huge: early melt means less
water when it is most needed in the
late summer.21
In the Northeast, researchers withthe U.S. Geological Survey (USGS)
have found that lakes are thawing
nine to 16 days earlier than they
were in 1850. This correlates with
a temperature increase during the
same time period in the region of
2.7 F.22 In addition, the USGS team
found that river ice thickness was
decreasing as well, by as much as 23
cm.23
Researchers at the University
of Wisconsin compiled data from
lakes and rivers across the Northern
Hemisphere to analyze the trend
in freeze and thaw dates. They
found that on average, that lakes
and rivers were freezing almost six
days later and thawing more than six
days early during the 1846 to 1995
period. Again, temperature recordsshowing a 2 F increase for the study
area show the fingerprint of global
warming.24
Changing the oddsa national
solution to global warming.
The impacts of global warming are
already being felt. If we are to avoid
the most catastrophic impacts, the
U.S. must take immediate action to
dramatically reduce its greenhouse
gas emissions. There is no silver
bullet, but we must implement
policies that:
Prevent irreversible harm to our
climate and our world.
Guarantee that global warming
pollution will go down and not up.
Assure enforceable deadlines for
making reductions.
The U.S. can produce substantial,
near-term reductions in domestic
greenhouse-gas emissions by using
market mechanisms to provide
companies with the incentives and
flexibility necessary for them to
take steps to reduce their pollution.
These mechanisms have been used
in the context of acid rain here in the
U.S. and are now being employed in
other parts of the world to address
climate change.
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SEASON CREEP HOW GLOBAL WARMING IS ALREADY AFFECTING THE WORLD AROUND US
Endnotes
1. Both, C. and Visser, M., May 17, 2001.
Adjustment to climate change is constrained
by arrival date in long-distance migrant bird.
Nature, Vol 411.
2. Intergovernmental Panel on Climate Change,
2001. IPCC Third Assessment Report Climate
Change 2001: Summary for Policy Makers.
3. Intergovernmental Panel on Climate Change,
January 2005.IPCC Third Assessment Report
Climate Change 2001: Summary for Policy
Makers, 2001; and World MeteorologicalOrganization, United Nations, WMO Statement
on the Status of the Global Climate in 2004:
Global Temperature in 2004 Fourth Warmest
(press release).
4. J. Hansen, R. Ruedy, M. Sato, and K. Lo,
NASA Goddard Institute for Space Studies and
Columbia University Earth Institute, December
2005. GISS Surface Temperature Analysis,
Global Temperature Trends: 2005 Summation.
5. Intergovernmental Panel on Climate Change,
2001. IPCC Third Assessment Report Climate
Change 2001: Summary for Policy Makers.
6. J. Osborn and K. Briffa, February 10, 2006.
The Spatial Extent of 20th Century Warming in
the Context of the past 1,200 years. Science.
7. Davis, M. and C. Zabinski, 1991. Changes in
geographical range resulting from greenhouse
warming: Effects on biodiversity in forests.
Yale University Press , New Haven, CT, 1992
and Huntley, B.How plants respond to climate
change: Migration rates, individualism and the
consequences for plant communities. Journal of
Botany 67:15-22.
8. Pyke, C., 2004. Habitat loss confounds climate
change impacts. Frontiers in Ecology and the
Environment: Vol. 2, No. 4, pp. 178182.
9. The IUCN Red List of Threatened Species,
2004. International Union for Conservation of
Nature and Natural Resources. http://www.
iucnredlist.org/info/tables/table1
10. Thomas, C. et. al, January 2004.Extinction
Risks from Climate Change. Nature 427, 145-148.
11. Root, T et. al., May 24, 2005.Human-
modified temperatures induce species changes:
Joint attribution. Proceedings of the NationalAcademy of Sciences, vol. 102, no. 21.
12. Schwartz, M., Ahas, R. and Aasa, A., 2006.
Onset of spring starting earlier across the
Northern Hemisphere. Global Change Biology,
12, 343-351.
13. Root, T. et. al., January 2, 2003. Fingerprints
of global warming on wild animals and plants.
Nature 421, 57-60.
14. Bradley, N. et. al., August 17, 1999.
Phenological changes reflect climate change
in Wisconsin. Proceedings of the National
Academy of Sciences, Vol. 96, Issue 17, 9701-9704.
15. Rock, B. and Spencer, S. 2001. Case study
2: the maple sugar industry. Chapter 5, New
England Regional Assessment. Available at
http://www.necci.sr.unh.edu/2001-NERA-
Foundation-Doc.html
16. Brown, J., et. al., 1999.Long-term trend
toward earlier breeding in an American bird: A
response to global warming? Proceedings of the
National Academy of Sciences, 96:5565-5569.
17. Dunn, P. and Winkler, D., 1999. Climate
change has affected the breeding date of
tree swallows throughout North America.
Proceedings of the Royal Society of London, B
266:2487-2490.
18. Edwards, M. and Richardson, A., August
2004. Impact of climate change on marine
pelagic phenology and trophic mismatch. Nature
430, 881-884.
19. Gibbs, J. and Breisch, A., 2001. Climate
warming and calling phenology of frogs near
Ithaca, New York, 1900-1999. Conservation
Biology 15:1175-1178.
20. Zhou, L. et. al., 2001. Variations in northern
vegetation activity inferred from satellite data of
vegetation index during 1981 to 1999. Journal o
Geophysical Research, Volume 106, Issue D17
21. Stewart, I. et. al., January 2004. Changes
towards earlier streamflow timing across
Western North America. Climatic Change, Vol.
62.
22. Hodgkins, G., Huntington, T., and
James II, I., December 16, 2002.Historical
changes in lake ice-out dates as indicators of
climate change in New England, 1850-2000.International Journal of Climatology, 22: 1819-
1827.
23. Hodgkins, G., Huntington, T., and Dudley,
R., 2003.Historical trend in river ice thickness
and coherence in hydroclimatological trends in
Maine. Climatic Change, 61: 217-236.
24. Magnuson, J., et. al., September 8, 2000.
Historical trends in lake and river ice cover in
the Northern Hemisphere. Science, vol. 289.
In 2005, as part of the mark-up
of the Energy Policy Act of 2005,
the Senate passed a bipartisan
resolution acknowledging the
science behind global warming and
calling for legislation to slow, stop
and reverse emissions of global
warming pollution, by mandatory
means. The resolution, offered by
Senators Jeff Bingaman (D-NM)
and Arlen Specter (R-PA), marks the
first time a majority of senators has
recognized the pressing need to take
action to address global warming.
Its time for Congress to make
good on the promise of that
resolution. We have the technology
to begin addressing this problem.
What is needed is political will. As
the evidence continues to mount
that global warming is here now and
is threatening everything from the
birds and the bees to our cities and
towns our leaders should rise to the
occasion and set national pollution
limits to begin dealing with the very
real threat of climate change.
8/9/2019 An Analysis of the Impact of Climate Change on Seasonal Cycles
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8/9/2019 An Analysis of the Impact of Climate Change on Seasonal Cycles
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