Reducing emissions of greenhouse gases

There is now widespread agreement that global warming can be mitigated by reducing emissions of greenhouse gases, as a matter of urgency

The term ‘mitigation’ is used here, in the context of climate change, to describe actions that will cut the rate of global warming.  The quicker this is done, the less cost will be incurred in adapting to the impact of climate change.

New research findings, by the Intergovernmental Panel on Climate Change (IPCC), have suggested that it would be prudent to limit the rise in global temperature above pre-industrial levels to 1.5°C – as described in a report, IPCC, 2018: Summary for Policymakers:

“Climate-related risks to health, livelihoods, food security, water supply, human security, and economic growth are projected to increase with global warming of 1.5°C and increase further with 2°C.” (see Section B5, and the summary in Figure SPM.2)

The new target of 1.5°C replaces the previous target of 2.0 °C, which was agreed to by the parties to the UN Framework Convention on Climate Change (UNFCCC) in 2015 – the Paris Agreement.  The UNFCCC structure enables targets to be agreed, but lets individual governments choose the most appropriate way ahead for their individual situations.

The IPCC report models four mitigation scenarios (in Section C):

“Different mitigation strategies can achieve the net emissions reductions that would be required to follow a pathway that limits global warming to 1.5°C with no or limited overshoot. All pathways use Carbon Dioxide Removal (CDR), but the amount varies across pathways, as do the relative contributions of Bioenergy with Carbon Capture and Storage (BECCS) and removals in the Agriculture, Forestry and Other Land Use (AFOLU) sector. This has implications for emissions and several other pathway characteristics.”

In short, reducing emissions of greenhouse gases more quickly would reduce the need for later removal of carbon from the atmosphere, referred to below as ‘geoengineering’ (

“The energy sector is at the front line of this issue, as it is by far the largest source of the emissions that cause global warming”, as the International Energy Agency (IEA) acknowledges in its Commentary: What would it take to limit the global temperature rise to 1.5 °C?; this report provides a summary of the available options for the industry and the agency’s estimates of their possible impact.

As described below, changes in behaviour and technical developments need to be encouraged (  Some alternatives to fossil fuels are already available (; these need to be adopted rapidly.  Innovative ways of reducing carbon emissions are possible (; research needs to be accelerated.



This page is intended to form part of Edition 4 of the Patterns of Power series of books.  An archived copy of it is held at https://www.patternsofpower.org/edition04/3572.htm