Schaefer Permafrost

8/16/2019 Schaefer Permafrost

1/65

When is the Permafrost

Carbon Tipping Point?

National Snow and Ice Data Center, Universit of Colorado

Ting!"n

#hang

Kevin Schaefer

Tim

Schaefer $in $i"%e

&lessio

'"smereli


2/65

Permafrost Primer

Skiklomanov [2007]

Permafrost: 'round at or

below 0°C for at least 2

consecutive years

Active ayer: & layer over

!ermafrost t"at free#es and

t"aws annuallyPermafrost $e%radation: &

decrease in !ermafrost

e&tent' an increase in active

layer t"ickness(


3/65

Permafrost Classification


4/65

Permafrost Classification by AreaPermafrost Classification by AreaContin"o"s ()*+ of area-

Discontin"o"s (.+/*+ of area-

Sporadic (0+/.+ of area-Isolated (10+ of area-

Brown et al 2, 0**34 Zhang et al 2, 0***


5/65

Permafrost Distrib"tion b Co"ntr


6/65

Permafrost ProfilePermafrost Profile

Active Layer

Vegetation

Permafrost


7/65

Permafrost Profile

56posed permafrost b river, Siberia

7Davis, 8+++9

Thermo:arst, &las:a


8/65

Crot"rbationCrot"rbation

; %ovement of soil or roc: d"e to%ovement of soil or roc: d"e to

repeated free


9/65

Permafrost =eat"resPermafrost =eat"res

Frost Heave, Yamal Stone Circles, Svalbard

Stone Circles, NW Territories Stripes, Glacier NP


10/65

Ice Wedges and PolgonsIce Wedges and Polgons

Poly%ons) *ena Poly%ons) Prud"oe +ay [,"an%) 200-]

Active Layer

Permafrost

Frozen

100th Winter

Frozen

1st Winter

Soil contracts& cracks

Thawed

1st Spring

Crack fills withwater & freezes

Thawed

100th Spring

Ice

Wedge


11/65

Ice $enses and $aersIce $enses and $aers

Active Layer

Permafrost

Year 1

Capillary

suction of

water to

permafrost

Water freezes

& expands

Year

1,000

Ice Layer

Ice Lens

Active Layer

Permafrost

Ice Lenses


12/65

Permafrost is $i:e ConcretePermafrost is $i:e Concrete

WicklandSchaefer


13/65

Thermo:arstThermo:arst

Slo!e .ountain) Alaska [Sc"aefer) 20/2]

; Thermokarst > s"bsidence or collapse of gro"nd

s"rface d"e to melting of gro"nd ice


14/65

Impacts of DegradationImpacts of Degradationoundation Settlin%

in C"ersky

1in%"ai3i#an% 4i%"way +rid%e

Alaska 5oad 4eaves

6"ermokarst in *akutsk [Skiklomanov) 200]


15/65

Impacts of DegradationImpacts of Degradation

Dring la:e, Tibet 7#hang, 8++9

@oc:fall, %atterhorn 7'r"ber, 8++A9 Ice/wedge thaw, &las:a 7Davis, 8+++9

Coastal 5rosion, &las:a


16/65

'lobal Carbon Ccle'lobal Carbon Ccle

0202* *+ 33

Bcean

A3,+++ 't

=ossil ="el

+++ 't

Permafrost 0 't

&tmosphere

.+ 't E A 't r /0

00*08+

Soils 0++ 'tFegetation ++ 't


17/65

Permafrost Carbon G"rial

PermafrostHori


18/65

Permafrost Carbon

A+,+++ ear old roots, Siberia7#imov et al2, 8++9%ammoth, Siberia

A8,+++ ear old grass, &las:a 0.,+++ ear old moss, North Slope

7Schaefer , 8+089


19/65

Permafrost Carbon =eedbac:

&mplification ofwarming d"e to release

of CB8 and CH from

thawing permafrost


20/65

%ethane @elease from Thawing Permafrost

K. Walter [email protected]

Thaw b"lb

Permafrost

Peat

Methaneproduction

Methane

emissionemissio

n Thermokarst

Erosion

Dead

plant &

animal

remains

+urnin% met"ane over a

t"ermokarst lake in

Siberia 89( alter;


21/65

IPCC &0G Scenario

200

300

400

500

600

700

800

160 2000 2040 2080 2120 2160 2200

Date (ear-

& t m o s p h e r i c

C B 8 ( p p m -


22/65

C"rrent Permafrost

&ctive $aer Thic:ness &$T (cm-&ctive $aer Thic:ness &$T (cm-


23/65

Pro!ected Permafrost DegradationHadC%A (med-HadC%A (med-

&ctive $aer Thic:ness &$T (cm-&ctive $aer Thic:ness &$T (cm-


24/65

Pro!ected Permafrost $oss

CCS%A (low-CCS%A (low-8* loss8* loss

HadC%A (med-HadC%A (med-.+ loss.+ loss

%I@BCA28 (high-%I@BCA28 (high-.* loss.* loss

Increase in &$T b 88++ (cm-Increase in &$T b 88++ (cm-


25/65

Permafrost Carbon Tipping Point

PC= Tipping

Point 8+8AJ

Date (ear-

C " m " l a t i v e

N 5 5 ( ' t C -

&rctic switches from a sin: to a so"rce


26/65

C"m"lative Permafrost Carbon =l"6

Date (ear-

P e r m a f r o s t C a r b o n = l " 6 ( ' t C -

0*+J

't

0+JA 't

.J8A of c"m"lative global land sin: (0+ 't C-5K"ivalent to 3J8* ppm


27/65

Fosto: Ice Core @ecords

; CB8 lags behind temperat"re b ++J++ r

3+ ppm


28/65

Paleo/Permafrost Carbon =eedbac:

Palaeocene


29/65

PC= and =ossil ="el 5missions

; Goth in!ect old carbon into atmosphere

; Goth irreversible

; &0G scenario> ++ ppm b 80++; 0A. 't C total emissions

; 0*+ 't C permafrost carbon fl"6

; 00. 't C fossil f"el emissions

; %"st red"ce fossil f"el emissions b additional0. or overshoot target climate


30/65

Concl"sions

; PC= can e6plain past climate variabilit

; PC= tipping point in mid 8+8+s

; PC= is strong> 0*+J 't C b 88++

; 5mission red"ctions m"st acco"nt for PC=

; Tell"s G paper> Schaefer et al2 78+009


31/65

Gac:"p SlidesGac:"p Slides


32/65

The SiGC&S& %odelThe SiGC&S& %odel

CB8 Temp

H"midit

N55$atent

Heat

Sensible

Heat

Snow

@

% o i s t " r e

T e m p e r a t " r e

C

a r b o n

Canop

Soil

'PP

Inp"t

Weather

Go"ndar $aer

f b i i


33/65

Permafrost Carbon in SiGC&S&

Dmin L ma6 &$T

d"ring spin"p

&ctive $aer

Thic:ness (&$T-

Soil

Carbon

Pools

Dmax L A m

&ctive $aer

Permafrost

Thawed Carbon

PermafrostCarbon Pool

&ctive $aer

Permafrost

Carbon Pool

Permafrost

; A0A 't C in permafrost carbon pool

; *0 't C in active laer

; 0 't C in top A m (.. 't C estimatedM-

MTarnocai et al. 78++*9

i S


34/65

56periment Set"p

; SiGC&S& E 5@&+ E &0G scenario

; Contin"o"sdiscontin"o"s permafrost

; 0*A/8++0> Ospin "pO

; 8++8/88++> random 5@&+ E linear trend; %I@BCA28 (high-

; HadC%A (med-

; CCS%A (low-

5 i i U i


35/65

5stimating Uncertaint

; 03 ensemble members; A warming rates

; A permafrost carbon densities

; 8 s"b/grid permafrost e6tents; Gest estimate> ensemble mean

; Uncertaint> ensemble standard deviation

IPCC &0G & i T


36/65

IPCC &0G &rctic Temperat"res

& i r T e m p e r a t " r e ( C -

CCS%A (low warming-

HadC%A (medi"m warming-

%I@CA28 (high warming-

&verage air temperat"re for permafrost regions

P f & $


37/65

Permafrost &rea $oss

Date (ear-

P e r m a f r o s

t & r e a ( , -

0*J. 't C8+AJA 't C 80AJ. 't C

= ' d 5= ' d 5


38/65

=ro


39/65

Atmos!"ere

=e%etation

Snow cover

>eot"ermal

?r%anic layer

Permafrost

+uffer

ayer

"at $rives Permafrost ormation@"at $rives Permafrost ormation@

G


40/65

Garrow,Garrow,

&las:a&las:a

Bbserved Soil

Temperat"re (C-0**/

%onth

S o i l D e

p t h ( m -

S n o w

D e p t h ( c m -

& i r

T e m p ( C -

Soil Temperat"re (C-

Bbserved Snow

Depth (cm-

8++8/A

Bbserved &ir

Temperat"re (C-

8++A/

epeate o ree


41/65

epeate o ree settling of gro"nd s"rface

when gro"nd ice meltswhen gro"nd ice melts

; Moisture Movement > soil moist"re moves from> soil moist"re moves from"nfro


42/65

Permafrost =eat"resPermafrost =eat"res

Frost Heave, Yamal Stone Circles, Svalbard

Stone Circles, NW Territories Stripes, Glacier NP

P f t D d ti 7IPCC 8++9P f t D d ti 7IPCC 8++9


43/65

Permafrost Degradation 7IPCC, 8++9Permafrost Degradation 7IPCC, 8++9

)A C increase

mid/0*.+s to 0**+

0 to A C increase

in past several

decades

+ to 0 C increase

since 0*+s

to C increase in 8+th Cent"r

8 to A C in last A+ ears

@ i P f t T t T d@ i P f t T t T d


44/65

/

/A

/8

/0

+

0

8

A

0*.+ 0*.. 0*+ 0*. 0*+ 0*. 0*3+ 0*3. 0**+ 0**. 8+++

Qear

T e m p e r a t " r e & n o m a l ( C -

0!2 m" Trend # $0!78%'decade0!4 m" Trend # $0!7%'decade

0!8 m" Trend # $0!65%'decade



@"ssian Permafrost Temperat"re Trends@"ssian Permafrost Temperat"re Trends

=ra"enfeld et al2 78++9#hang et al2 78++.9

@ i & ti $ T d@ i & ti $ T d


45/65

@"ssian &ctive $aer Trends@"ssian &ctive $aer Trends

/+2A

/+28

/+20

+

+20

+28

+2A

0*.. 0*+ 0*. 0*+ 0*. 0*3+ 0*3. 0**+ 0**. 8+++

Qear

& c t i v e $ a e r D e p t h

& n o m a l ( m - 0*+R0**3 Change> E8. cm

=ra"enfeld et al2 78++9#hang et al2 78++.9

T li: D l tT li: D l t


46/65

Tali: DevelopmentTali: Development

Seasonally

frozen

ground

Talik

Permafrost

; Talik > Unfro


47/65

Permafrost CarbonPermafrost Carbon

; 08 't C in permafrost08 't C in permafrost77Tarnocai et al.Tarnocai et al., 8++*9, 8++*9

; .+ 't C in atmosphere.+ 't C in atmosphere

@oots, Siberia 7 Zimov et al 2, 8++9

H"m"s, Siberia 7 Davis, 8+++9%ammoth, Siberia

P ! ti f P f t D d tiPro!ections of Permafrost Degradation


48/65

Pro!ections of Permafrost DegradationPro!ections of Permafrost Degradation

; 'eneral Pattern> lose area from the so"th,'eneral Pattern> lose area from the so"th,

increase active laer thic:ness everwhereincrease active laer thic:ness everwhere

Source

5eduction in

Permafrost Area

by 2/00 8;

Bncrease in

Active ayer

6"ickness 8cm;

Schaefer et al 2 78+0+9 0*/83

Zhang et al 2 78++39 0/0* A+/3+

Saito et al 2 78++9 + 0++/A++

awrence an! Slater 78++.9 *+ .++

awrence et al 2 78++39 *+ .++

= db : t &t h=eedbac:s to &tmosphere


49/65

=eedbac:s to &tmosphere=eedbac:s to &tmosphere

; 5nerg balance5nerg balance; Snow &lbedo =eedbac: Snow &lbedo =eedbac:

; Fegetation &lbedo =eedbac: Fegetation &lbedo =eedbac:

;

Sea Ice $oss and &rctic &mplificationSea Ice $oss and &rctic &mplification; Gowen ratio seasonalitGowen ratio seasonalit

; Trace 'as =eedbac:sTrace 'as =eedbac:s; CBCB88 =ertili


50/65

Net 5cosstem 56change (N55- Net 5cosstem 56change (N55-

; N55 1 + means net carbon "pta:e

N55 L @espiration / Photosnthesis

5nhanced bPermafrost

Carbon

=eedbac:

5nhanced b CB8

=ertili


51/65

.3J0* 't C b 88++ is a lot of carbon.3J0* 't C b 88++ is a lot of carbon

; A2. of permafrost carbonA2. of permafrost carbon

; 8J* ppm8J* ppm increase comparableincrease comparable

Fosto: Ice Core (3+ ppm-Fosto: Ice Core (3+ ppm-

; 0A/8 of global land sin: 0A/8 of global land sin:

; J0 of fossil f"el emissionsJ0 of fossil f"el emissions

for ++ ppm targetfor ++ ppm target

Wal:ing Points on PermafrostWal:ing Points on Permafrost


52/65

Wal:ing Points on PermafrostWal:ing Points on Permafrost

; =ree


53/65

When is the Permafrost Carbon

Tipping Point?

Kevin Schaefer ", Ting#$n Zhang " ,

ori Br$hwiler % , &n!rew P. Barrett "

0 National Snow and Ice Data Center, Universit of Colorado8

NB&& 5arth Sstem @esearch $aborator

Bbserved Permafrost


54/65

Bbserved Permafrost

@oc: Circle =ormation


55/65

@oc: Circle =ormation

56pand o"t in winter when fro


56/65

Permafrost &rea b Co"ntr

Permafrost Class b Co"ntr


57/65

Permafrost Class b Co"ntr

Seasonall =ro


58/65

=ariations of area e&tent of seasonally fro#en

%round and snow in t"e ort"ern 4emis!"ere

durin% t"e winter of /--DE--(

Seasonall =ro


59/65

.ont"ly ma&imum area

e&tent of seasonally fro#en

%round

Seasonally fro#en %round

is FG & /0G km2 or GD of

t"e land area in t"eort"ern 4emis!"ere(

Seasonall =ro


60/65

ClimateEeat"er

>eot"ermal

"eat flu&

>round

tem!erature re%ime

6"ermal diffusion

eHuation

Soil t"ermal

!ro!erties

1I 14 1 J 0

Soil moisture

conditions

Sites!ecific factors

8albedo) rou%"ness)slo!e) as!ect) snow)

soil te&ture) etc(;

& Permafrost %odel

%odeling Permafrost


61/65

Snow

Atmos!"ere

ower +oundary

ro#en

%round

Permafrost or

unfro#en %round

6"awed

%round

.ovin% !"ase !lane: heat cond"ction

with or witho"t phase change

.ovin% !"ase !lane

Heat cond"ction

Snowsoil interface: "eat cond"ction with

or witho"t phase change

k = k s( )

hs(t) = (x,t)

C= C Fr (x,T)

k = k Fr (x, T)

C= C Fr (x,T)

T(Z fr ) = T f

k = k Th (x, T)

C = C Th(x,T)

T(Z th ) = T f

.ovin% boundary> heatcond"ction in deforming medi"m

+oundary condition: Prescribed temperat"re, orheat fl"6, or s"rface energ balance

+oundary condition: !rescribed

temperat"re or heat fl"6

%odeling Permafrost

P f t l ifi tiP f t l ifi ti


62/65

Permafrost classificationPermafrost classification

; +y area covera%e+y area covera%e; Continuous 8K-0 of area;Continuous 8K-0 of area;; $iscontinuous 80-0 of area;$iscontinuous 80-0 of area;; S!oradic 8/00 of area;S!oradic 8/00 of area;; Bsolated 8L/0 of area;Bsolated 8L/0 of area;

; +y ocation:+y ocation:; 6errestrial6errestrial; SubiceSubice; SubseaSubsea;

5elic5elic; +y Cou!lin% wit" climate:+y Cou!lin% wit" climate:

; round $ata Products


63/65

ro#en >round $ata Productsro#en >round $ata Products

; http>nsidc2orgfgdc

; &rctic 5&S5/'rid =ree


64/65

Permafrost .onitorin%Permafrost .onitorin%



65/65


Dthreshol! ' 0*A/8++0 ma6im"m active laer depth

Dactive ' active laer depth

Slow (3+-

%etabolic(.-

Str"ct"ral

(0.-

Soil Carbon Pools

Dthreshol!

Permafrost

Carbon Pool

Dactive

Dthreshol!

Dactive

Thawed Carbon

Permafrost

Carbon Pool

Documents

Schaefer Permafrost