global warming of 1.5°c - ercst...2019/01/01  · 1 global warming of 1.5 c an ipcc special report...

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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

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adia

tive

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ing

[Wm

−2]

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1986 1990 1994 1998 2002 2006 2010 2014

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●●

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AB

C

1520

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(b) Anthropogenic CO2 emissions

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CH

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1 ]

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AB

C

250

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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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B C

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1213

1986 1990 1994 1998 2002 2006 2010 2014

(d) Anthropogenic N2O emissions

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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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