1 March, 2014

Implications of potentially lower climate sensitivity on climate projections and policy

Authors

Joeri Rogelj, Malte Meinshausen, Jan Sedláček and Reto Knutti

Climate sensitivity, the long-term temperature response to CO2, has been notoriously difficult to constrain until today. Estimates based on the observed warming trends favor lower values, while the skill with which comprehensive climate models are able to simulate present day climate implies higher values to be more plausible.

We find that much lower values would postpone crossing the 2 °C temperature threshold by about a decade for emissions near current levels, or alternatively would imply that limiting warming to below 1.5 °C would require about the same emission reductions as are now assumed for 2 °C. It is just as plausible, however, for climate sensitivity to be at the upper end of the consensus range.

Publications

1.5°C-aligned 2030 and 2035 GHG emissions targets

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Spatially resolved emulated annual temperature projections for overshoot pathways

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Climate Action Tracker: 2024 warming projection update

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Decarbonising light-duty vehicle road transport

The Climate Action Tracker provides updated 1.5ºC compatible benchmarks for the transport sector for the world as a whole and for seven individual countries; the US, EU, China, India, Brazil, South Africa and Indonesia.

Emissions Gap Report 2024: No more hot air … please!

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The role of northern forests in limiting warming to 1.5°C

Northern forests are critical in the race to net zero CO₂ by mid-century. Protecting and restoring these forests, alongside steep and rapid reductions in fossil fuel emissions, is essential both to mitigating emissions and to supporting forest ecosystem services and biodiversity.

Methodology underpinning the State of Climate Action series: 2024 update

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Rapid urbanisation and climate change key drivers of dramatic flood impacts in Nepal

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LNG shipbuilding industry heading to huge oversupply

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Fracking the Kimberley: the Canning Basin development plans

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Decarbonisation targets and 1.5℃ pathways

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