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Global Warming of 1.5°C
An IPCC special report on the impacts of global warming of 1.5°C above pre-
industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global
response to the threat of climate change, sustainable development, and
efforts to eradicate poverty.
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Thereportinnumbers
91Authorsfrom40 Countries
133Contributingauthors
6000Studies 1113Reviewers
42001Comments
UnderstandingGlobalWarmingof1.5°C
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Global Context
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N2O
Other GHG
CH4
CO2
AerosolsR
adia
tive
Forc
ing
[Wm
−2]
−10
12
34
1986 1990 1994 1998 2002 2006 2010 2014
(a) Radiative forcing
CO
2 em
issi
ons
[Gt C
O2
y−1 ]
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●●
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AB
C
1520
2530
3540
1986 1990 1994 1998 2002 2006 2010 2014
(b) Anthropogenic CO2 emissions
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GCP2017EDGARv4.2
CH
4 em
issi
ons
[Tg
CH
4y−
1 ]
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AB
C
250
300
350
400
450
1986 1990 1994 1998 2002 2006 2010 2014
(c) Anthropogenic CH4 emissions
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●
EDGARv4.2US−EPA_2012
N2O
em
issi
ons
[Tg
N2O
y−1 ]
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● ● ● ● ●A
B C
89
1011
1213
1986 1990 1994 1998 2002 2006 2010 2014
(d) Anthropogenic N2O emissions
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EDGARv4.2US−EPA_2012
Where are we now?
Since preindustrial times, human activities have caused approximately 1.0°C of global warming.
• Already seeing consequences for people, nature and livelihoods
• At current rate, would reach 1.5°C between 2030 and 2052
• Past emissions alone do not commit the world to 1.5°C
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EmissionPathwaysandSystemTransitionsConsistentwith1.5°CGlobalWarming
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Greenhouse gas emissions pathways
• To limit warming to 1.5°C, CO2 emissions fall by about 45% by 2030 (from 2010 levels)
• To limit warming to 1.5°C, CO2 emissions would need to reach ‘net zero’ around 2050
• Reducing non-CO2 emissions would have direct and immediate health benefits
o Compared to 20% for 2°C
o Compared to around 2075 for 2°C
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Greenhouse gas emissions pathways
• Limiting warming to 1.5°C would require changes on an unprecedented scale
o Deepemissionscutsinallsectors
o Arangeoftechnologies
o Behaviouralchanges
o Increaseinvestmentinlowcarbonoptions
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ProjectedClimateChange,PotentialImpactsandAssociatedRisks
Impacts of global warming 1.5°C
• Less extreme weather where people live, including extreme heat and rainfall
• By 2100, global mean sea level rise will be around 10 cm lower
• 10 million fewer people exposed to risk of rising seas
At 1.5°C compared to 2°C:
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Impacts of global warming 1.5°C
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