Greenhouse gas emissions are still increasing, and they must stop soon

The IPCC report found that we will likely exceed 1.5℃ of warming even if all of the countries that have pledged to reduce emissions actually meet those goals. There is already a gap in the implementation of promised climate action; policies in place by the end of 2020 fall short of what U.N. member nations promised. Additionally, the IPCC found that in scenarios that limit warming to 1.5℃, there’s another gap in 2030 between where the Nationally Determined Contribution pledges get us, and where emissions need to be.

Since 2010, global GHG emissions have increased across all major sectors. Although energy produced from fossil fuels has become more efficient, those improvements are overshadowed by increased overall activity. The report found that global carbon intensity, a measurement of the efficiency of energy produced from carbon, was decreasing, but not enough to achieve global temperature goals.

Additionally, in all of the models that limit warming to 1.5℃, our global GHG emissions peak by 2025. Even then, the report notes that rapid, deep, and immediate emissions reduction must follow throughout the next 30 years. The IPCC projects that based on policies currently in place, we’re going to miss this mark. The goal is to limit warming to 1.5℃; we’re currently projected to see 3.2℃ this century.

Low-emissions technology is getting more affordable

As low-emissions technology options improve and their cost declines, the IPCC finds they now present a viable alternative to fossil fuels. From 2010–2019, the global cost of clean technologies decreased 85 percent for solar power, 55 percent for wind power, and 85 percent for advanced batteries essential for energy storage. Additionally, deployment of solar technology has increased tenfold and electric vehicles are 100 times more prevalent.

The IPCC report found that several policy instruments can both reduce the cost of green technologies and stimulate their adoption. Publicly funding research and development for these technologies can lower production costs and improve their overall energy potential. When governments fund demonstration and pilot projects, like this one in Massachusetts, public support often increases because their benefits become more apparent.

Low-emissions technologies can cut emissions, and can do so at a lower cost. The IPCC estimates that by 2030, mitigation strategies costing $100 or less per ton of carbon dioxide (CO2) saved each year could reduce emissions by half of the 2019 levels. A large portion of the reductions come from strategies that cost less than $20 per ton of CO2. These include generating solar and wind energy, improving energy efficiency measures, protecting ecosystems, and reducing the emissions of other powerful GHGs, like methane.

We can’t afford any more fossil fuel infrastructure

The IPCC report finds that we have no room left for additional fossil fuel infrastructure. The IPCC’s scenarios that limit warming account for a certain amount of “allowed” GHG emissions in the coming decades, known as the carbon budget. The report finds that the amount of GHG emissions that will be released from existing and planned fossil fuel infrastructure will exceed that budget by more than two times. This means that if we use the fossil fuel infrastructure that we already have to the end of its lifetime, we will likely miss our climate targets.

So gas wells, oil rigs, and coal mines may need to be decommissioned while they still have viable resources and economies need to transition to other sources of energy. At the very least, it’s clear that there is no room left in the budget for any additional fossil fuel infrastructure.

Among the carbon that’s budgeted on the path to reach net zero emissions, the electricity sector needs to be an early convert to low-emission alternatives. In the IPCC’s scenarios that limit warming to 2℃, most of the remaining emissions before global net zero are projected to occur outside of the power sector, mainly in transportation and industrial processes. That’s because those two sectors are much harder to decarbonize than the electricity sector. The IPCC’s suggestions to decarbonize the power sector include: decommissioning and reducing fossil fuel infrastructure, retrofitting existing installations with carbon capture technology, switching to lower carbon fuels, and canceling new coal installations that don’t incorporate carbon capture.

Some of the carbon in our atmosphere needs to go

The IPCC report found that we must remove some atmospheric carbon if the planet is to reach net zero emissions. Carbon Dioxide Removal (CDR) is any human activity that removes CO2 from the atmosphere and stores it in soil, plants, a geologic reservoir, or even the ocean. CDR has been met with some resistance, with criticism about the high costs, effectiveness, and the potential risks involved. 

The different methods of CDR vary widely in their feasibility, potential benefits, and potential risks. Some methods, such as altering the ocean’s chemistry to absorb more carbon, are emerging technologies, while others, such as reforesting previously vegetated areas, have had a long record of success. There is also a range in each method’s potential for GHG reduction. For example, protecting the natural carbon sinks in coastal and marine ecosystems has far less emissions reduction potential than agroforestry, the integration of trees and shrubs into agriculture.

One of the most costly methods, but also the one with the longest time scale for storage, is called Direct Air Capture and Carbon Sequestration (DACCS). This technology removes CO2 directly from the air and stores it underground, like a reversal of fossil fuel extraction. This method has the potential to store carbon for tens of thousands of years, however it is expensive and would be difficult to implement at a large scale.

Some methods for CDR come with co-benefits other than reducing atmospheric carbon, while others have unintended consequences associated with them. Nature-centric methods such as reforestation, improved forest management, soil sequestration, and blue carbon management can all enhance biodiversity and local livelihoods. Whereas, some other potentially effective methods like afforestation, establishing forests on land where they didn’t previously exist, and producing vegetation mass for biochar, a concentrated form of charcoal that traps carbon, can have adverse effects on biodiversity, food and water scarcity, and rights of Indigenous Peoples. These negative effects can be magnified when these methods are implemented at a large scale.

Policies need to be thoughtfully designed and effectively implemented

The IPCC report found that policy packages are more effective than individual policies, and they should enable innovation and build capacity. Cross-sectoral packages that contain policies that complement one another can reduce barriers and increase the efficacy of each policy. For example, Illinois’ Climate and Equitable Jobs Act addresses providing 100 percent clean electricity and contains provisions for power plant closures and supporting workforce development. Throughout the last decade, the body of scientists found the most effective policy packages have been tailored to specific countries and regions.

By 2020, greater than 20 percent of GHG emissions were covered by market-based policies, though the IPCC report found that carbon pollution prices alone are insufficient. The report found that economic instruments like these have been most effective when they’re complemented with regulatory policies. Carbon pollution pricing, for instance, incentivizes low-cost emissions reduction measures, but hasn’t been very effective in promoting higher-cost options that will be necessary for further reductions.

Both public and private investment in climate mitigation is lower than what was promised by U.N. member nations, and far lower than it needs to be. Currently, public and private investments are still greater for fossil fuels than for climate adaptation and mitigation. Climate investments were increasing in the last decade, but have slowed down since 2018. In that year, global climate finance was below the collective goal under the Paris Agreement to mobilize $100 billion per year by 2020. 

The feasibility of solutions differs across all sectors and regionally, but what’s consistent is that barriers to climate solutions need to be removed or reduced, and enabling conditions need to be strengthened. Enabling conditions are factors such as finance, technological innovation, and policy instruments that make mitigation measures easier to be implemented.

The readiness of certain technologies factors into the potential feasibility of those mitigation measures. For example, wind and solar power, electrification of urban systems, green infrastructure, and reduction of food waste, are all technically viable solutions that are generally supported by the public. The public support and technical viability enables the deployment of these GHG emissions reduction measures.

References:

1. IPCC Sixth Assessment Report — Climate Change 2022: Mitigation of Climate Change — Summary for Policymakers, Intergovernmental Panel on Climate Change, 4/4/2022