The Intergovernmental Panel on Climate Change released a special report this week on the impacts of 1.5°C global warming. The report looks at “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”.
The report was written by 91 scientists from 40 countries. They analysed 6,000 scientific studies. Needless to say, it’s pretty tough reading.
Fortunately, there’s a Summary for Policymakers that’s only 34 pages long. It tells us that warming of 1.5°C is less disastrous than 2°C warming. And that the sooner we reach zero greenhouse gas emissions, the better.
To achieve this, greenhouse gas emissions have to be reduced by 45% from 2010 levels by 2030, and 100% by 2050.
The IPCC report includes a graph showing what this would look like:
The graph illustrates the problem very clearly. Since 1992, the UN Framework Convention on Climate Change has met 23 times. These UNFCCC discussions have utterly failed to reduce CO2 emissions. Yet from 2020, emissions have to drop dramatically, if we are to stand a chance of keeping global warming below 1.5°C.
The Summary for Policymakers states that,
The rates of system changes associated with limiting global warming to 1.5°C with no or limited overshoot have occurred in the past within specific sectors, technologies and spatial contexts, but there is no documented historic precedent for their scale.
Last year, about US$333.5 billion was invested in renewable energy, according to Bloomberg. The IPCC report asks for US$2.4 trillion to be invested in renewable energy every year to 2035.
“Net zero” emissions by 2040
The IPCC is talking about emissions reaching “net zero” by 2040 (or 2050). The IPCC’s pathways for keeping global warming to 1.5°C use carbon dioxide removal – sucking CO2 out of the atmosphere, or “negative emissions”.
The Summary for Policymakers points out that there are “multiple feasibility and sustainability constraints” to doing this on a scale large enough to make a difference. And the report argues that,
Significant near-term emissions reductions and measures to lower energy and land demand can limit CDR deployment to a few hundred GtCO2 without reliance on bioenergy with carbon capture and storage (BECCS).
The report looks at four model pathways, all of which rely on Agriculture, Forestry and Other Land Use to remove carbon dioxide from the atmosphere and three of which include BECCS (click on the image for a larger version):
Vast areas of land
Limiting global warming to 1.5°C would require “rapid and far-reaching transitions in energy, land, urban and infrastructure (including transport and buildings), and industrial systems”, the IPCC report states.
Land use is currently a source of greenhouse gas emissions. In a paragraph on land use, the IPCC explains that in the model pathways, somewhere between 1 and 7 million square kilometres of agricultural land is converted to energy crops. (Australia covers an area of 7.6 million km2.)
Meanwhile the area of forests ranges from a one million km2 reduction to a 10 million km2 increase.
While a footnote explains that no single pathway uses the upper limits for land use changes simultaneously, these are nevertheless very large areas of land.
The report notes that,
Such large transitions pose profound challenges for sustainable management of the various demands on land for human settlements, food, livestock feed, fibre, bioenergy, carbon storage, biodiversity and other ecosystem services…. The implementation of land-based mitigation options would require overcoming socio-economic, institutional, technological, financing and environmental barriers that differ across regions.
In a response to the IPCC report, Professor Kevin Anderson at the University of Manchester writes that the report “meticulously lays out how the serious climate impacts of 1.5°C of warming are still far less destructive than those for 2°C”.
But Anderson is critical of the report’s suggestions for addressing climate change. He points out that “almost 50% of global carbon emissions arise from the activities of around 10% of the global population, increasing to 70% of emissions from just 20% of citizens”. Imposing a per-capita carbon footprint limit on the top 10% of global emitters equivalent to that of an average European citizen, would reduce global emissions by one-third in a couple of years, Anderson writes.
Ignoring this huge inequality in emissions, the IPCC chooses instead to constrain its policy advice to fit neatly within the current economic model. This includes, significant reliance on removal of carbon dioxide from the atmosphere much later in the century, when today’s senior scientists and policy makers will be either retired or dead. Conjuring up such futuristic ‘negative emission technologies’ to help achieve the virtually impossible 1.5°C target is perhaps understandable, but such intergenerational buck-passing also dominates the IPCC’s 2°C advice.
As if to confirm that business as usual will continue, the day after the IPCC’s report came out, the International Monetary Fund and the World Bank Group’s Annual Meeting started in Bali, Indonesia. About 4,500 people flew to Bali for the meeting.
And the BBC’s Newsnight programme invited climate change denier Myron Ebell to talk about the IPCC’s report.