La tonne de carbone a-‐t-‐elle une valeur ?

La#tonne#de#carbone#a,t,elle#une#valeur#?#
!
!"#!$%&!'(!)*+!,#!-.!/.0+1!2!&#1+-!2!3#!4+0!5.!36#007.!#8915.!590:!*0.!09*,.33.!49+-!
3#! )*.-/+90! 5*! :;#0<.=.0/! :3+=#/+)*.! )*+! >9*1! 36+0-/#0/! 06#! /9*?9*1-! >#-! 7/7! 17<37.@!
A.>*+-! )*6.33.! -.! >9-.B! 3.-! 7=+--+90-! 5.! <#C! 2! .44./! 5.! -.11.! DEFGH! )*+! .0! -90/!
1.->90-#83.-! 90/! #*<=.0/7! 5.! IJK! #391-! =L=.! )*.! 3.-! 5+4471.0/.-! $%&! #,#+.0/! 3.*1!
175*:/+90!2!3.*1!9151.!5*!?9*1@!"#!5+44+:*3/7!>1+0:+>#3.!,+.0/!5*!:#1#:/M1.!.N/1L=.=.0/!
5+44*-! 5.! :.-! 7=+--+90-@! G+! >#1! 890;.*1! +3! O! #,#+/! *0! 1.->90-#83.! +5.0/+4+#83.B! +3! -.1#+/!
-#0-!59*/.!8.#*:9*>!>3*-!4#:+3.!5.!>1.051.!5.-!=.-*1.-B!:9==.!>#1!.N.=>3.!#,.:!3.!
>1983M=.! 5.! 369C90.B! 17<37! >9*1! 36.--.0/+.3! >#1! 3.! >19/9:93.! 5.! P90/17#3B! #,.:!
36+0/.15+:/+90! 5.-! <#C! D$Q$H! .0! :#*-.@! P#+-! 5#0-! :.! :#-B! 3.-! >195*:/.*1-! 7/#+.0/!
>1+0:+>#3.=.0/! #*! 09=81.! 5.! /19+-! D3.-! #=71+:#+0-! R$R!./!A*! &90/! 5.! S.=9*1-! ./!
36.*19>7.0!T/9:;.=H!./!+3-!#,#+.0/!2!3.*1!5+->9-+/+90!3.-!-*8-/+/*/-!)*+!>.1=.//#+.0/!5.!
:90/+0*.1!:9==.!#,#0/B!/9*/!.0!73+=+0#0/!36+=>#:/!-*1!369C90.@!
! U9*/! #*! :90/1#+1.B! 5#0-! 3.! :#-! 5*! :;#0<.=.0/! :3+=#/+)*.B! +3! O! #! >3*-! 5.! -.>/!
=+33+#15-! 5.! 1.->90-#83.-! #*! /1#,.1-! 5.! 3.*1-! 57:+-+90-! 5.! >195*:/+90! ./! 5.!
:90-9==#/+90@! F/! +3! O! #! 'VW! X/#/-! -9*,.1#+0-! )*+! 90/! 8+.0! 5*! =#3! 2! -.! :915900.1! .0!
1.090Y#0/!#391-!07:.--#+1.=.0/!2!*0.!>#1/!5.!3.*1!-9*,.1#+0./7@!"#!Z!-93*/+90![!/19*,7.!
2! $9>.0;#<*.! #! :90-+-/7! 2!-.! 5900.1! *0! ;91+C90! .0! 'JWJ! 9\! 3698?.:/+4! .-/! 5.! 0.! >#-!
57>#--.1! 3.-! ']$! 56#*<=.0/#/+90! 5.! /.=>71#/*1.! .0! :90/1#5+:/+90! #,.:! /9*/.-! 3.-!
/1#?.:/9+1.-!.0,+-#<7.-!>#1!3.-!-:+.0/+4+)*.-@!$9==.!.0!'JWJB!3#!>3*>#1/!5.!07<9:+#/.*1-!
#:/*.3-! 0.! -.190/! >3*-! #*! >9*,9+1B! 3.! 1+-)*.! )*6+3-! >1.00.0/! #*?9*156;*+! 4#:.! 2! 3.*1-!
73.:/.*1-!.-/!8+.0!4#+83.@!
! ".-! >1.*,.-! 5.! :.! <+<#0/.-)*.! >1983M=.! 5.! :9915+0#/+90! -90/! #,.*<3#0/.-@! T*!
0+,.#*!<398#3B!3.!4#+/!=L=.!)*690!.0!-9+/!2!3#!,+0</!./!*0+M=.!$%&!#391-!=L=.!)*.!3.-!
7=+--+90-! 5.! EFG! :90/+0*.0/! 2! #*<=.0/.1! .0! -90/! *0.! 5.-! +33*-/1#/+90-! 3.-! >3*-!
=#1)*#0/.-@!T*!0+,.#*!5.-!X/#/-B!:.//.!#8-.0:.!5.!:9915+0#/+90!-.!=#0+4.-/.!#*--+!>#1!3#!
5+,.1-+/7!5.-!>93+/+)*.-!-*1!3.!:;#0<.=.0/!:3+=#/+)*.!./!-*1!3.-!>93+/+)*.-!70.1<7/+)*.-@!
E#C!5.!-:;+-/.!./^9*!:;#1890!>9*1!3.-!*0-!D_GT!./!$;+0.!.0!>#1/+:*3+.1HB!=+N!70.1<7/+)*.!
;7/719<M0.! >9*1! 56#*/1.-! D0*:37#+1.! .0! Q1#0:.! ./! 793+.0! .0! T33.=#<0.HB! :;#)*.! >#O-!
=M0.!-#!>93+/+)*.!70.1<7/+)*.!.0!490:/+90!5.!-.-! +0/71L/-! +==75+#/-! D9*!5*!=9+0-!5.!
:.*N! )*6+3! >.1Y9+/! :9==.! /.3-HB! #=70#<.! -90! /.11+/9+1.! -.390! -.-! >19>1.-! :1+/M1.-B!
:90-/1*+/!-#!=98+3+/7!.0!490:/+90!5.!-.-!:90/1#+0/.-!D>1.--+90!5.-!:90-9==#/.*1-!./!5.-!
:90-/1*:/.*1-B!G_`!#*N!_GT!./!<#C93.!.0!Q1#0:.B!`93a-b#<.0!.0!T33.=#<0.H@!R3!.0!.-/!5.!
=L=.!>9*1!3#!4+-:#3+/7!:#1890.B!0*33.!>9*1!:.1/#+0-!D_GTHB!/1M-!73.,7.!>9*1!)*.3)*.-!*0-!
D(JJ!.*19-!.0!G*M5.H!./!8#38*/+#0/.!>9*1!8.#*:9*>@!R3!.-/!7,+5.==.0/!39<+)*.!)*.!3.-!

-+/*#/+90-!5.!:;#)*.!>#O-!7/#0/!5+4471.0/.-B!+3-!06#+.0/!>#-!3.-!=L=.-!:;9+NB!=#+-!)*.!:.-!
:;9+NB!)*.3-!)*6+3-!-9+.0/B!:90/+0*.0/!2!+=>3+)*.1!<398#3.=.0/!5.-!7=+--+90-!:19+--#0/.-!
=90/1.!8+.0!)*.!3.!-9*:+!5.!3.*1!8#+--.!06.-/!>#-!+0/7<17!:9==.!*0.!:90/1#+0/.!491/.!>#1!
3.-!5+4471.0/-!F/#/-@!
! Q#:.!2!:.//.!-+/*#/+90!>9*1!3.!=9+0-!:90/1#-/7.B!*0!:.1/#+0!09=81.!567:909=+-/.-!
17>*/7-!90/!/19*,7!3#!-93*/+90!c!*0!>1+N!=905+#3!5*!:#1890.!>.1=.//#0/B!>#1!-90!*0+:+/7B!
5.!5900.1!3#!8900.!+0:+/#/+90!2!/9*-B!:905*+-#0/!.04+0!2!:.//.!175*:/+90!/#0/!.->717.!5.-!
7=+--+90-!5.!EFG@!T--9:+7!2!:.!>1+NB!3#!=+-.!.0!>3#:.!5.!=7:#0+-=.-!D890*-d=#3*-B!/#1+4-!
59*#0+.1-B! .0:9*1-! 5.! 5.//.-! -9*,.1#+0.-H! ./! 56+0-/+/*/+90-! D.N+-/#0/.-! ./^9*! 2! :17.1H!
>.1=.//1#+/! 5.! 17-9*51.! 3.-! >1983M=.-! 567)*+/7! ./! 5.! >#1/+:+>#/+90! )*+! 839)*.0/! >9*1!
36+0-/#0/!/9*/.!-93*/+90!#*!>1983M=.!:3+=#/+)*.@!
!$6.-/!>.*!5.!5+1.!)*.!:.//.!Z!-93*/+90![!1.-/.!.N/1#915+0#+1.=.0/!/;791+)*.B!/#0/!
3.-!:905+/+90-!=+0+=#3.-!)*+!>.1=.//1#+.0/!5.!36.0,+-#<.1!0.!-90/!>#-!17*0+.-!./!0690/!
<*M1.!5.!:;#0:.!5.!36L/1.!5#0-!3.-!>19:;#+0.-!57:.00+.-@!%0! 0.!,9+/!>#-!8+.0!>#1!)*.3!
=+1#:3.!3.-!>1+0:+>.-!7,9)*7-!>#1!:.-!7:909=+-/.-(!#*1#+.0/!3#!,.1/*!5.!57839)*.1!5.-!
07<9:+#/+90-!)*+!.0/#=.0/!3.*1!,+0</!./!*0+M=.!19*05!D+3!-.=83.!)*.!3690!06#+/!>#-!#--.C!
=75+/7! -*1! 3#! 5+44+:*3/7! +05+)*7.! >#1! :.! 09=81.H@! ".-! #8#0590-! 5.! -9*,.1#+0./7!!
+=>3+)*7-! >#1! 3#! :17#/+90! 56+0-/+/*/+90-! #O#0/! 519+/! 56+0/.1,.0/+90! D9*! 36#//1+8*/+90! 5.!
09*,.33.-! :9=>7/.0:.-! 2! 5.-! +0-/+/*/+90-! .N+-/#0/.-HB! 5.-! -#0:/+90-! :175+83.-! 9*! 5.-!!
/1#0-4.1/-!4914#+/#+1.-!2!<1#05.!7:;.33.!-*>>9-.0/!)*.!3.-!>1983M=.-!5.!:9915+0#/+90!)*+!
-90/!2!3#!-9*1:.!5.-!5+44+:*3/7-!#:/*.33.-!-.190/!4+0#3.=.0/!-*1=90/7-!>#1!3#!-.*3.!,.1/*!
5.!/19+-!>1+0:+>.-!#44+1=7-!>#1!5.-!Z!.N>.1/-![@!
P#+-!4+0#3.=.0/!:./!#1<*=.0/!5.!17#3+-=.!>9*11#+/!0.!>#-!L/1.!#*--+!57:+-+4!5#0-!
3#!=.-*1.!9\!3#! -93*/+90! 5.! 09-! 7:909=+-/.-B! -+!.33.!.-/!:.1/.-!5+44+:+3.! 2! +=>37=.0/.1B!
-.1#+/! 07#0=9+0-! 3#! ,9+.! 2! -*+,1.B! -#0-! 59*/.! #15*.! =#+-! .44+:#:.! >9*1! 17<3.1! 3.!
>1983M=.!:3+=#/+)*.@!A.!4#+/!3.!>1+N!*0+)*.!5*!:#1890.!0.!-.1#+/!)*6*0!98?.:/+4!5.!>3*-!
390<!/.1=.B!,.1-!3.)*.3!+3!-6#<+1#+/!5.!:90,.1<.1!>#1/#0/!56*0.!:9#3+/+90!+0+/+#3.!5.!>#O-!
#O#0/!,9:#/+90!2!-67/944.1!#*!4*1!./!2!=.-*1.@!$.!-.1#+/!:.1/#+0.=.0/!4#+1.!>.*!5.!:#-!5*!
/+=+0<!+=>3+:+/.!D'JWJ!:6.-/!5.=#+0!./!+3!.-/!>.*!>198#83.!)*62!:.//.!5#/.!3.!>19:.--*-!5.!
:90,.1<.0:.! -9+/! #:;.,7H! ./! 5.! 3#! :175+8+3+/7! 5.! 3#! Z!:9#3+/+90! +0+/+#3.!['! =#+-! .-/d:.!
=#3<17!/9*/!3#!8900.!-93*/+90!e!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
(!&1+N!*0+)*.!5*!:#1890.B!>#1/+:+>#/+90!*0+,.1-.33.B!#8-.0:.!5.!>#--#<.1!:3#05.-/+0@!
'!$.1/.-B!3.-!07<9:+#/+90-!>173+=+0#+1.-!2!3#!$%&!'(!+05+)*.0/!)*.!3#!$;+0.!./!3.-!X/#/-d_0+-!DfJK!
5.-!7=+--+90-!=905+#3.-!2!.*N!5.*NH!-.!-90/!.0<#<7-!-*1!5.-!175*:/+90-!5#0-!*0!#,.0+1!>19:;.!
D#*/9*1!5.!'J'J^'J'WH@!%0!09*-!>.1=.//1#!5.!09*-!17?9*+1!5.!:.-!.0<#<.=.0/-!)*#05!+3-!-.190/!
:90-/#/7-B!/#0/!36;+-/9+1.!>#--7.!09*-!#!+0:+/7!2!L/1.!>1*5.0/!D,9+1!3.!4905!,.1/!5.!(JJ!=+33+#15-!
#:/7!2!$9>.0;#<*.!)*+!06#!<*M1.!7/7!-*+,+!56.44./-H@!

&9*1!3.!:19+1.B!+3!4#*/!>.0-.1!)*.!3#!/900.!5.!:#1890.!#!*0.!,#3.*1!+0/1+0-M)*.!)*+B!
*0.! 49+-! )*690! 36#! Z!17,737.![! >.*/! ?*-/.=.0/! -.! /1#5*+1.! >#1! :.! >1+N! -+<0#3#0/! :.//.!
,#3.*1B! #391-! =L=.! )*.! :.! )*.! =90/1.0/! 3.-! =*3/+>3.-! 7,#3*#/+90-! 5.-! .N/.10#3+/7-!
.0,+1900.=.0/#3.-!:6.-/!3.*1!.N/1L=.!5+,.1-+/7!>9*1!3.!=L=.!8+.0!9*!-.1,+:.@!"9+0!5.!
=.-*1.1!*0.!,#3.*1!+0/1+0-M)*.!5.!3#!/900.!5.!:#1890.B!09*-!=.-*190-!3.-!,#3.*1-!)*.!
09*-! 3*+! #::91590-B! :9=>/.! /.0*! 5.! 09-! :90/1#+0/.-! ./! 5.! 09-! >17471.0:.-@! F/! :9==.!
:.33.-d:+!-90/!3#1<.=.0/!5+4471.0/.-B!>#1:.!)*6.33.-!17-*3/.0/!5.!3#!:90/+0<.0:.!;+-/91+)*.!
./! 5.-! 5O0#=+)*.-! -9:+7/#3.-B! ,9*39+1! +=>9-.1! *0! >1+N! *0+)*.! :6.-/! 1.4*-.1! 5.! ,9+1! 3#!
5+,.1-+/7!5*!=905.!./!3.! :19+1.! 2!36+=#<.!5.!3#!/;791+.!9\!36#<.0/!1.>17-.0/#/+4!-*44+/!2!
:9=>1.051.! 3.-! :9=>91/.=.0/-@! $6.-/! >1.051.! 3#! /;791+.! >9*1! 3.! =905.! ./! 4#+1.! 5*!
=95M3.!3#!17#3+/7!2!3#)*.33.!+3!-*44+1#+/!5.!-.!:90491=.1@!
R3!0.!-.1#+/!-#0-!59*/.!>#-!-+!*/+3.!56*0!>9+0/!5.!,*.!9>71#/+900.3!5.!:;.1:;.1!2!
5+-:*/.1!:.//.!+57.!4#14.3*.!56*0!>1+N!*0+)*.!5*!:#1890.!5#0-!3.!=905.!17.3B!/#0/!90!>.*/!
L/1.!:.1/#+0!)*6.33.!0.!-.1#!?#=#+-!=+-.!.0!g*,1.!0+!=L=.!>1+-.!.0!:90-+571#/+90!>#1!3.-!
F/#/-!391-!5.!3#!$%&'(!D./!=L=.!5.!3#!$%&'W!9*!f'!)*+!1+-)*.0/!8+.0!56.N+-/.1!#*!1O/;=.!
9\!-.!>1.00.0/!3.-!57:+-+90-H@!$#1!3.!>1983M=.!:3+=#/+)*.!06.-/!>#-!56#8915!*0!>1983M=.!
7:909=+)*.B!:6.-/!*0!>1983M=.!>93+/+)*.!./!-6+3!.-/!-+!5+44+:+3.!5.!-.!=.//1.!56#::915!-*1!
5.-! 57:+-+90-! 5.! 175*:/+90! 5.-! 7=+--+90-! 5.! EFG! )*.! /9*/! 3.! =905.! #*?9*156;*+!
-6#::915.!2!/19*,.1!07:.--#+1.-B!:6.-/!)*.!5.11+M1.!3#!175*:/+90!5.-!7=+--+90-!+3!O!#!/9*/.!
3691<#0+-#/+90!5.!3#!>195*:/+90!./!5.!3#!:90-9==#/+90!2!1.>.0-.1!2!09*,.#*N!41#+-!:.!)*+!
0.!>.*/!)*.!;.*1/.1!5.!>*+--#0/-!+0/71L/-!.0!>3#:.!)*+!0690/!>#-!3.!8+.0!:9==*0!:9==.!
>179::*>#/+90!>1+0:+>#3.@!
!
Gilles#Rotillon##