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Ch. 27 Climate Change
The Ecology of Climate ChangeEarth’s rotation affects the amount of sunlightstriking the different parts of the globe and causesthe seasons
Tilt of Earth’s axis varies from 22.5 to 24 over acycle of 41,000 yearsThis is responsible for the ice ages- glacial expansion
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The Ecology of Climate Change
Variations in climate have been affecting life onEarth and its evolution over geologic timeClimate influences the function of naturalecosystemsThe current widely accepted belief is that humanshave the ability to alter Earth’s climate and they aredoing so1896 : Arrhenius published the first calculation ofglobal warming from human emissions of CO2
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http://www.paulchefurka.ca/Population.html
The Ecology of Climate Change
Since the Industrial Revolution began, the burningof fossil fuels has led to an exponential increase inthe concentration of carbon dioxide and othergreenhouse gases in the atmosphere
This has led to a general pattern of warming overthe past century
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1300 - 1850.
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Earth’s Climate Has Warmed over the PastCentury
Earth’s climate has warmed by an estimated 0.74 Cover the past century
The rate of warming during the second half of thecentury has been about double that of the first half
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1970s 0.00
!"#$ &$$'#( )"*+",#-'," . °/0
0.18 1980s
1990s
3.2 1.5 1 .6 .3 .1 .1 .3 .6 1 1.5 2 1.5 1 .6 .3 . 1 .1 .3 .6 1 1.5 2.2
0.31 0.51 2000s
Polar regions have warmed themost (Artic)The winter months show thegreatest warmingMinimum temperatures haverisen twice as fast as maximum10% decrease in snow cover/iceextent since the late 1960s
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All things are not equal -The Temperature is changing unevenly
Ocean Temperature Change
Average global ocean temperature has increased toa depth of at least 3000 feet
The ocean has absorbed > 80% of the added heat
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Figure 27.2a
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30
35
40
45
1900 1920 1940 1960 1980 2000
Year
N o r t h e r n
H e m
i s p h e r e s p r i n g
s n o w c o v e r ( m
i l l i o n
k m 2 )
.#0 12,-3",$ 4"*56+3","
Figure 27.2b
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8
6
4
10
12
14
1900 1920 1940 1960 1980 2000 Year
A r c t i c s u m m e r s e a
i c e
e x t e n t ( m i l l i o n k m
2 )
.70 &,8-58 6'**", 6"# 58" "9-"$-
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Warming of ocean surface is largest overthe Arctic Ocean
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0
10
20
10
20
1900 1920 1940 1960 1980 2000 Year
C h a n g e i n g l o b a l a v e r a g e u p p e r
o c e a n h e a t c o n t e n t ( 1 0 2 2 J )
.80 :(27#( #;",#<" 3"#- 82$-"$- 2= -3" '++", 28"#$ >#-",6
Rising sea levelsWarming causes seawater to expand, raising thesea level
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Figure 27.2d
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50
0
50
100
150
200
1900 1920 1940 1960 1980 2000 Year
G l o b a l a v e r a g e
s e a l e v e l c h a n g e ( m m
)
.?0 &;",#<" 6"# (";"(
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Precipitation from 1950 - 2010. Precipitation trend is inmm/day over the period of observation. Stippling indicates theobserved trend is statistically significant (From Dai 2011).
75
60
45
30 15
0
15
30
45
60 180 120 60 60 0 120 180
Longitude
Precipitation trend (mm/day/50yr), 1950-2010
L a t i t u d e
4.0 2.0 1.0 0.4 0.2 0 0.1 0.2 0.4 1.0 2.0 4.0
Changes in precipitation have not beenspatially or temporally uniform
Climate Change Has a Direct Influence on thePhysiology and Development of Organisms
How does temperature affect organisms?Is there a difference in the effect on endotherms
versus ectotherms?How could the global patterns of warming seen overthe last century impact organisms?
Are some groups more vulnerable to the effects ofwarming than others?
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CC influence on Physiology andDevelopment of Organisms
Endotherms have a constant body temperatureEnvironmental temperatures affect metabolism,determining heat exchange with the environment
The larger the body size, the less surface area forheat dissipationGeographic trend for average body size to increasewith decreasing mean annual temperature
In both birds and mammals, a smaller body size is
more energetically efficient in a warm climate
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Ectotherm metabolic activity increasesexponentially with temperature, rather thenlinearly
If a species is at the upper thermal tolerance limit, thenthe species might be in troubleDillion from Univ. of Wyoming showed that ectothermswere more vulnerable to temperature rises in tropicalregions
Metabolic rates increased more quickly in thetropics than in the temperate or artic regions!WHY?
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Ectotherms
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1970s 0.00
!"#$ &$$'#( )"*+",#-'," . °/0
0.18 1980s
1990s
3.2 1.5 1 .6 .3 .1 .1 .3 .6 1 1.5 2 1.5 1 .6 .3 . 1 .1 .3 .6 1 1.5 2.2
0.31 0.51 2000s
(Data from Dillon et al. 2010.)
0.5
0
0.5
1.0
1.5
2.0
10
0
1980 1990 2000 2010
10
20
30
40
50
Tropical North temperate
South temperate
Arctic
C h a n g e i n t e m p e r a
t u r e ( ° C )
C h a n g e i n m e t a b o l i c r a t e
Year 1980 1990 2000 2010
Year
.70 /3#$<" 5$ *"-#72(58 ,#-"6 5$?5==","$- ,"<52$6
.#0 /3#$<" 5$ *"#$ -"*+",#-'," 2;",@ A"#,6 5$ ?5==","$- ,"<52$6 2= <(27"
( W
p e r g 3 / 4 b o d y
m a s s )
Several species ofporcelain crabs live in theintertidal of the easternPacificThe upper thermaltolerance limits – LT 50
temperature at which 50%mortality occurs
Thermal Tolerance
25 15 20 30 35 40 45 26
28
30
32
34
36
38
40
42
10
California Chile
N. Gulf of California Panama
Maximal habitat temperature ( °C)
L T 5 0
( ° C )
Species above theline are okbecause the maxlethal temperatureis above what themax habitattemperature is inthe environment.
Thermal ToleranceTropical species generally have a currentmaximum habitat temperature (MHT) closer to
their LT 50
Relatively small ability to increase LT 50 throughacclimationOther tropical invertebrates living in intertidalzones are have shown similar vulnerabilitiesHypothesis = tropical ectotherms are morethreatened by CC than species from mid-latitudes because tropical species livecloser to their temp limit
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Thermal Tolerance
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400
600
800
1200
1000
18 20 22 24 26 28 30 32 34 36 38 40 Body temperature ( °C)
Body temperature
.5
1
0 Tolerance range
“Optimal” temperature
(T opt )
Upper criticaltemperature
(T max )
Lower criticaltemperature
(T min )
R e l a t i v e p e r f o r m a n c e
S p r i n t s p e e d
( m m p e r s e c )
Impacts on terrestrial plant species are morecomplicated
Response of plants to changes in climate involve
Temperature
Precipitation
Sometimes CO 2 as a fertilizer
Regional changes affect soil and microhabitatconditions
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Terrestrial Species’ Response to CC
Tree Growth
In the past century analysis of tree rings shows:
The temperate forest of Eastern North America
correlated to an increase in the length of thegrowing season
In Western North America, increasing droughtsassociated with increase in mortality
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Figure 27.6
Pacific Northwest California Interior
FirPineHemlockOther
B"? C$?58#-" C$8,"#6" !2,-#(5-A D('" 5$?58#-52$ ?"8,"#6"
3 2
1
2.0
1.5
1.0
0.5
0.0
Year
M o r t a l i t y r a t e
( % / y r )
M o r t a l i t y r a t e
( % / y r )
1960 1980 2000
2.0
1.5
1.0
0.5
0.0 1960 1980 2000
Mixed results from studies of the response oftree growthSome studies have shown localized increasesthe past 50 years of warmingMost showed declines in growth rates andincreases in mortality related to water stressSites from the entire boreal forest region ofCanada were studied from 1963-2008 (96sample plots)
Tree mortality rates increased, greater in thewest than the east
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ArcticFigure 27.7
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4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
Western region
2000 2010 1990 1960 1970 1980
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0 2010 2000 1990 1960 1970 1980
Year Year
D,5-563 /2('*75#
&(7 ,-# E#6F#-83 >#$
#$5-27#
G$-#,52
H' 7 8
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
Trembling aspen Jack pine Black spruce White spruce
2000 2010 1990 1960 1970 1980 Year
T r e e
m o r t a l i t y
( p e r c e n t p e r y e a r )
T r e e m o r t a l i t y
( p e r c e n t p e r y e a r )
T r e e m o r t a l i t y
( p e r c e n t p e r y e a r )
Eastern region
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http://www.nasa.gov/topics/earth/features/shrub-spread.html
Shrub Expansion in Northern Quebec
Global vegetation models predict rapid polewardmigration of tundra and boreal forest vegetation inresponse to climate warming
Low shrub and grass-like vegetation in tundracontributed preferentially to the greening trend,while forested areas were less likely to showsignificant trends in Normalized DifferenceVegetation Index (NDVI)
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20120010311.pdf
Phenology- timing of seasonal activity
Many processes related to activity
Migration
Reproduction
Hibernation
Many studies show that activities that take place inspring have occurred earlier and earlier since the1960s
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My trip to Alaska January 2014England - 47 year studyof common woodlandbirds (1961-2007)
Mean egg-laying datehas become earlier byabout 14 days,beginning in the mid-1970s
Anne Chamantier, Oxford University
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10
20
30
40
1960 1970 1980 1990 2000 Year
Mean laying date declinedover the study period - theyare laying their eggs earlier
Mean laying date1= April 1
Migratory birdsStudy of 20 migratory bird species that breed inEngland and winter in sub-Saharan Africa
For 17 of the 20 species, the arrival date inEngland has been earlier in response toincreases in temperature trends in Africa
The departure date has also advanced, so thelength of time in England is the same, but startsabout 8 days earlier (data span 30 years)
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Figure 27.9
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1971 1976 1981 1986 1991 1996 2001
M e a n a r r i v a l d a t e
M e a n
d e p a r t u r e d a t e
Year
150
140
130
120
110
100
90
80
70
60
340
330
320
310
300
290
280
270
260
250
Meta Analysis-Impact of CC on plants and animals in Europe
203 plant and animal species
Overall, shifts are larger at higher latitudes
Amphibians had a greater shift toward earlybreeding times than other taxonomic groups
2x as fast as trees, birds, butterflies
Butterfly emergence or migratory arrival advanced
3x as fast as first herbaceous plant flowering
Parmesan 2007
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10
5
10
0
5
15
20
25
30
35
C h a n g e i n s p r i n g
t i m i n g
( d a y s / d e c a d e )
Amphibian Bird Shrub
Tree
Fish Fly Mammal Butterfly
Herbs and grass
Individual species
Most species are experiencing advanceof spring activity in Alberta regions
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http://onlinelibrary.wiley.com/doi/10.1111/gcb.12382/abstract
• Study of 92 tree species in the easternUnited States from 1999-2009
• No consistent evidence that shifts in thesepopulations are greatest in areas whereclimate has changed the most
• Results suggest that for 77% and 83% of thetree species, juveniles have higher optimaltemperature and optimal precipitation,respectively, than adults
• Tree species might respond to climatechange by having faster turnover as dynamicsaccelerate with longer growing seasons andhigher temperatures , before there is evidenceof poleward migration at biogeographicscales
Study (1942 to 2002) shows that the cover of alder,willow and dwarf birch has been increasing
most obvious on hill slopes and valley bottoms
Studies in Canada, Scandinavia, and parts ofRussia have reported similar findings
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Arctic northern expansion of shrub species
Plant surveys in 1977 vs. 2007 in So. Cal. overan elevation gradient30-year period
0.4 C increase in mean tempprecipitation variability increaseddecreased snow cover
Average elevation of the dominant plantspecies increased by 65 m;
All species except one showed a distributionshift up the mountain range
Range ShiftsFigure 27.15
100
50
0
50
100
150
200
C h a n g e i n e l e v a t i o n
( m )
CC & Geographic Distribution of Species
Direct influence on species-specific temperaturetolerancesHigher elevation distribution are constrained byminimum temperaturesMinimum temperature are rising
CC Impact on Species Interactions
Often reproduction is timed to correspond to
resource availabilityFor herbivores, this is the plant growing season
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Study conducted over six summers in westernGreenland
Monitored caribou calving season and plantphenology (timing and progression of emergence)
Successful caribou reproduction depends onsynchrony of calving with resource abundance
In the far north, plant nutrient content and digestibilitypeak soon after emergence and then decline rapidly
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CC Impact on Species Interactions
Onset of plant growing season (based on plantspecies emergence) advanced by 14.8 days
Onset of calving advanced by 1.28 daysThis results in a rapidly developing mismatchbetween caribou reproduction and food supply
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CC Impact on Species Interactions
2001 120
130
140
150
160
2002 2003 2004 2005 2006 Year
D a t e s o f 5 % e m e r g e n c e
o r b i r t h s
Caribou
Forage species
There is a difference in the environmental cues thattrigger each event
Caribou are cued by changes in day length
same from year to year
The growing season of the plants is correlated withmean spring temperature
increased by 4.6 C during the study
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CC Impact on Species Interactions
0
0.2
0.4
0.6
E a r l y c a l f m o r t a l i t y
Calf mortality increased as the degree of mismatch increased
0 0.5 1.0 0
0.2
0.4
0.6
Index of trophic mismatch
C a l f p r o d u c t i o n
Calf production decreased as the degree of mismatch increased
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Lake Systems and CC
Changes in phenology of phytoplankton andzooplankton populations in Lake Washingtonbetween 1962 - 2002
Spring (Mar - June) water temperatures showedsignificant warming trendsThe upper 10m water layer increased in temperaturean average of 1.4 C over 40 years
In response to this warming, the springphytoplankton bloom advanced by 27 days overthose 40 years
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1970 1960 1980 1990 2000 March
April
May
June
6
8 10 12
14
16
18
W a t e r
t e m p e r a t u r e
( ° C )
Increasing trend in temperatureover in the top 10-m water in Lake Washington
1970 1960 1980 1990 2000
)5*5$< 2= -3" ?5#-2* 7(22*
80
100
120
140
D a y o f y e a r
100
120
140
160
180
D a y o f y e a r
1970 1960 1980 1990 2000
Relation of Daphnia densities in May to the mismatch(in days) between the timing of diatom bloom andDaphnia peak for the period of 1977 – 2002
Mountain pine beetle (native to western North America) attacks most trees in the genus Pinus
can erupt into epidemics
Over the past ten years, these epidemics have beenlarger than previously recorded
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Region has experiencedincreased temperaturesincreased frequency of drought
This has decreased tree health and increasedsusceptibility to beetlesRegional warming has led to range expansion ofthe beetle, especially at higher elevationsWarming has also affected the beetle’s life history
The beetle flight season (flying to attack new trees)starts one month earlier and lasts twice as long
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Forest Systems and CC
Historical life history patternof single generation per year
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Recent life history patternof two generations per year
As a result, some beetle populations havetwo generations in a year instead of one
Forest Systems and CC
Arctic Fox vs Red Fox
Red fox – its northern range limit is determined bytemperature limitation
Arctic fox – its southern limit is determined byinterspecific competition with the red fox
Arctic warming for the past 40 years has allowedred fox populations to expand north, leading to adecline in Arctic fox populations
Shifts in species composition and diversity
Examination of the impact of climate warming onplant communities in the Santa Catalina Mountains
– comparison with data from 1963 resampled 2011
During that time
the mean annual rainfall has decreased
the mean annual temperature has increased by0.25 C per decade between 1949 and 2011
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Plant Communities and CC
Resampled the original elevation transectFocused on the 27 most abundant species
75 % of the species now grow in a more narrow range
some shifting as much as 1000ft up the slope
Figure 27.19a
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M e a n a n n u a l t e m p e r a t u r e
( C )
22
21
20
19
181950 1960 1970 1980 1990 2000 2010
Year
M e a n a n n u a l r a i n f a l
l ( m m
)600
450
300
150
0
.#0
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Figure 27.19b
Juniperus deppeana var. deppeana
Pseudotsuga menzesi i var. glauca
Quercus emoryi
Quercus hypoleucoidesRobina neomexicana
WOODYSHRUBS
Ceanothus fendleri
Mimosa aculeaticarpa
Brickellia californica
Pteridium aquilinum
Thalictrum fendleri
SMALLSHRUBSAND HERBS
Agave schottiiDasylirion wheeleri
Yucca madrensisSUCCULENTS
Aristida ternipes var. ternipes
Muhlenbergia emersleyi
Urochloa arizonicaGRASSES
2500 3000 4000 5000 6000 7000 8000 9000Elevation (feet)
Muhlenbergia porteri
Bouteloua curtipendula
Nolina microcarpa
Packera neomexicana
Lotus greenei
Arceuthobium vaginatum
Garrya wrightii
Arctostaphylos pungens
Quercus gambelii
Quercus arizonica
Pinus strobiformis
TREES
White bars are 1963 elevational range data black bars represent 2011 elevationdata from the current study.
Study of calanoid copepods (crustaceans – zooplankton) in the eastern North Atlantic andEuropean shelf seasCompared distribution 1958 - 1999 and seasurface temp change
177,000 samples collectedhas monitored 1946
Ocean Systems and CC
Increases in regional sea surface temperatureshave led to a major reorganization ofzooplankton species composition andbiodiversity in the entire North Atlantic Basin
All associations show consistent, long-term changesWarmer-water species moved north by 10 latitudeColder-water species retreated to the north
This is more pronounced than any movement seenfor terrestrial organisms
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Ocean Systems and CC
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These types of geographical shifts may haveserious consequences for North Sea fisheriesIf they continue, could lead to changes in fishabundanceStocks of northern species, such as cod, coulddecline or even collapse
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Ocean Systems and CC
Net primary productivity and decomposition aretwo key ecosystem processes
These control energy and nutrients in theecosystem
Climate has a direct influence on both processesSite-based studies of local ecosystems can bedifficult to interpret because there are multiplefactors influencing these ecosystems
soils, topography, CO 2 concentrationCurrent studies used data from satellites
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Ocean Systems and CC
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Net Primary Productivity
Net primary productivity (NPP) is defined asthe net flux of carbon from the atmosphere intogreen plants per unit time
Energy potential available for the next trophic level
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CC impact on NPP
Net primarily productivity estimated from satellite-based measures of absorbed
can examine temporal and spatial changes
Study from 1982 - 1999
Global changes in climate have eased climaticconstraints on plant growth and NPP increased 6%over the 18-year study
largest increase in tropical ecosystems
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Figure 27.22a
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Change in mean NPP (1982 –1999) (percentage per year)1.5 1.5
.#0
0
A more recent analysis used the same methodsbut extended the analysis to cover 2002-2009
The decade between 2000 and 2009 is thewarmest recorded since instrumentalmeasurements started
Results suggest a reduction in NPP of 0.55petagrams of carbon as a result of regional dryingthat would constrain plant growth
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CC impact on NPP
Figure 27.23a
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21 14 7 0 7 14 21NPP trend (2000 –2009) (gC/m 2 /yr)
.#0
Spatial patterns of NPP over the past decade havenot been globally consistentNPP has increased over large areas in the NorthernHemisphere
65% of vegetated land area had an increaseNPP has generally decreased in the SouthernHemisphere
70% of vegetated land area had a decreaseHigher temperatures lead to increased evaporationand reduced water availability
CC impact on NPP
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Are humans to blame for CC?
The preindustrial level of atmospheric carbondioxide was 280 parts per million (ppm)
The level will double sometime this century
In October 2015 it was 398 ppmCarbon dioxide is not the only greenhouse gas,other significant components include:
methane (CH 4)chlorofluorocarbons (CFCs)hydrogenated chlorofluorocarbons (HCFCs)nitrous oxide (N 2O)
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Greenhouse gases in the atmosphere warm Earth’ssurface
What effect will doubling the concentration of carbondioxide in the atmosphere have on global climatesystems?
General circulation models (GCMs ) are complexcomputer models of Earth’s climate system Give insight into the influence of increasing CO 2 concentration on large-scale patterns of globalclimate
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Are humans to blame for CC?
There are some consistent patterns in thepredictions from these GCMs
an increase in average global temperatureIntergovernmental Panel on Climate Change report(2013) suggests a global average surface temperatureincrease of 1.1 to 6.4 C by 2100Last glacial maximum had decrease 5
!
C
an increase in global precipitationThese changes would not be evenly distributed
greatest warming during winter months and innorthern latitudes
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Are humans to blame for CC?
)"*+",#-',"
)"*+",#-',"
I,"85+5-#-52$
I,"85+5-#-52$
J"8 K#$ L"7
K'$" K'(A &'<
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5
( C)
0.8 0.6 0.4 0.2 0 0.2 0.4 0.6 0.8
(mm day 1)
0 0.5 1 1.5 2 2.5 3.5 4 4.5 5.5 6 6.5 7 7.53 5
( C) (mm day 1)
0.8 0.6 0.4 0.2 0 0.2 0.4 0.6 0.8
1980-1999
2080-2099
What are the models saying?Increasing climate variation is predicted
more stormsgreater snowfallincreased variability in rainfall
The predictions that rising concentrations ofgreenhouse gases will significantly affect globalclimate in the future are consistent
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QuestionsWhat are the sources of uncertainty in predicting theresponse of ecological systems to future climatechange?
What type of investigations are being undertaken toexamine possible impacts of future climate change?
What are some models used to investigate theresponse of biosystem to climate change?
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Uncertainty in Predicting EcologicalResponse to CC
Uncertainty in predicting ecological systemsresponse to future climate change
the limitations in our understanding of processes thatcontrol the current distribution and abundance ofspeciesthe uncertainly associated with the specificpredictions of how the climate in a given region willchange in response to GHGs
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Research is being conducted at all levels oforganization, from individual to global scaleThe studies fall into two categories:
examining the response of ecological systems toexperimental warming and the associatedenvironmental factorsusing models of ecological systems to evaluate theresponse to future climate scenarios
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Uncertainty in Predicting EcologicalResponse to CC
A number of experimental studies in variousenvironments (tropical to polar) show thatcommunities and ecosystems respond strongly towarming
Most studies have been done at a single location fora short period of time
Comparison among studies is difficultdiverse techniques used to produce warming
experimentally
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Uncertainty in Predicting EcologicalResponse to CC
International Tundra Experiment (ITEX) is acoordinated international effort using standardizedmethods
Network of Arctic and alpine research sitesthroughout the worldExperimental and observational studies usestandardized protocols to measure responses oftundra plants and plant communities to increases intemperatureInvestigators from 13 countries working at 11 sites
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Figure 27.25
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.#0 .70
4
32
1
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Passive warming treatmentsIncreased plant-level air temperature by 1 – 3 C
This is in the range of observed and predicted tundraregion warming
Responses were rapid, detected in whole plantcommunities after two growing seasons
increased height and cover of deciduous shrubs andgrassesdecreased cover of mosses and lichensdecreased species diversity
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Network of Ecosystem Warming Studies
Experiments focus on the response of soilrespiration, net nitrogen mineralization, andaboveground NPPThere are 32 research sites in four broadly definedbiomes
high (latitude or altitude) tundra, low tundra,grassland, forest
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MinnesotaPeatlands
HowlandForest
Ny Alesund Flakaliden
CLIMEX
Buxton
WythamWoods
HarvardForest
Rio MayoHuntingtonForest
Oak Ridge
RockyMountain
NiwotRidge
ShortgrassSteppe
TERA
ToolikLake
Abisko
Results show considerable variation in response towarming
Across all sites, experimental warming (0.3 to 6.0 C)for 2 to 9 years durationIncreases were seen in
soil respiration rates, by 20%larger in forested ecosystems
Net nitrogen mineralization Organic N -> N2 rates inc.by 46%NPP, by 19%
larger in low tundra ecosystems
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The Future
Most research focuses on developing mathematicalmodels that can provide information on futureclimate change impactsThe bioclimatic envelope model is one of the mostwidely applied modeling approaches to investigatethe response of speciesQualitative relationship between climate and speciesgeographic distribution
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Figure 27.27
The quantitative relationship betweenspecies distribution and current climatecan then be used to predict the potentialdistribution of the species under changedclimate conditions.
The current distribution of the species (reddots represent local populations) is relatedquantitatively to features of the climate,such as mean annual temperature (shownas temperature isopleths).
Temperature ( C)
A b u n d a n c e
20 21 22 23
Current ClimateConditions
18 C19 C
20 C
21 C
22 C
23 C
23 C
20 C
21 C
22 C
19 C
24 C
Longitude
L a t i t u d e
Longitude
L a t i t u d e
Projected FutureClimate
ConditionsThis relationship can be used to map the possiblegeographic range of the species under differentclimate change scenarios
Investigation of the effect of climate change on 134tree species in the eastern United States with 36environmental variables
Climate change could have large impacts onsuitable habitat for these tree species
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The Future
FIA-Current RF-Current
GCM3 Avg Hi GCM3 Avg Lo
< 1 1 –3 4 –6 7 –10 11 –20 21 –30 31 –50 > 50E'<#, *#+(" . &8", 6#883#,'* 0
FIA-Current RF-Current
GCM3 Avg Hi GCM3 Avg Lo
.70 E(#63 +5$" . I5$'6 "((52--55 0< 1 1 –3 4 –6 7 –10 11 –20 21 –30 31 –50 > 50
FIA - Current RF - Current
GCM3Avg Lo GCM3Avg Hi
White/Red/JackSpruce/FirLnglg/SlshLobolly/Shrtif
Oak/PineOak/HickoryOak/Gum/CyprElm/Ash/Ctnw
Maple/Beech/BirchAspen/BirchNoDat/NoFor
By combiningindividual speciesinto groups basedon forest types,potential changesin the geographicdistribution offorest communitiescould be examined
Projected changes in climate and tree species richness for NorthAmerica under future climate change scenario of CGCM2 (2071-2100)
)"*+",#-'," I,"85+5-#-52$ E+"85"6 ,583$"66
3 to 22 to 11 to 0
0 –11 –22 –2
< 6060 to 3030 to 2020 to 0
0 –1010 –2020 –3030 –60
119 to 8584 to 6160 to 3938 to 2120 to 65 to 10
11 –2627 –4546 –84
Degrees C % of current values Tree richness
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Predicting Future Climate Change Requires anUnderstanding of the Interactions between the Biosphere
and the Other Components of Earth’s System
• The global carbon cycle links the atmosphere,hydrosphere, biosphere, and geosphere on aglobal scale
• 50% of the carbon released through humanactivities remains in the atmosphere
• Of the remaining 50%,• 26% is taken up by terrestrial ecosystems• 24% is taken up by the oceans
• forms carbonic acid, which increases surface acidity
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• Diffusion is the primary factor controlling theexchange of carbon between the atmosphereand surface waters
• On land, the major factors are• the net uptake of carbon by terrestrial
ecosystems as NPP - carbon storage
• the loss of carbon from terrestrial ecosystems indecomposition
• The difference in the rate between these twoprocesses is net ecosystem productivity (NEP)
Net Ecosystem Productivity
Net Ecosystem Production, NEP amount of carbonaccumulated by the ecosystem
NEP = GPP - (R plant + R heterotrophs + Rdecomposers)
A measure of Net Ecosystem Production is of greatinterest when determining the CO 2 balancebetween various ecosystems, or the entire earth,and the atmosphereModels try to simulate the basic processes of NPPand decomposition
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Net Ecosystem Productivity • In order to predict the fate of future CO 2 emissions
• NPP increases and there is a net removal ofcarbon dioxide – negative feedback
• NPP decreases (or decompositionincreases) and there is a net addition ofcarbon dioxide – positive feedback
Terrestrial biosphere model developed at thePotsdam Institute for Climate ImpactResearch
• Terrestrial plants groups attributes• C3 or C4• Deciduous vs Evergreen• Woody or Herbaceous
• P/S & Respiration modeled• atmospheric and soil condition
• Rates of decomposition organic matter
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• Terrestrial biosphere model used futureclimate change scenarios based on five
general circulation models• Results show great uncertainty in thepredicted patterns of carbon exchange
• This is mainly the result of large differencesin climate projections for each model
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2
0
2
41900 1940 1980 2020 2060 2100
C-SOURCE
C-SINK
P g C
/ y r
In 3 out of the 5 climate projection the terrestrialbiosphere was a source of carbon to the atmosphere bythe year 2100. With would imply that we have a positivefeed back loop.
Can we do anythingabout climate change
and should we?
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Earth and Environmental System PodcastDr. Christain Shorey
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http://inside.mines.edu/~cshorey/pages/sygn.html
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