APCAG Executive Briefing | One Earth
Achieving the Paris Climate Goals in the COVID-19 era

Achieving the Paris Climate Goals in the COVID-19 era

A breakthrough climate model, the product of a two-year collaboration with 17 leading scientists, shows that we still have a window to stay below the dangerous threshold of 1.5 degrees Celsius, achieving net-zero emissions before 2040.



As the world recovers from the COVID-19 pandemic, we must think carefully about the future that we want to build. We face a worsening climate crisis, with record temperatures causing rampant fires, rapidly melting polar ice, and extreme flooding. The world has already reached a global average temperature rise of 1.1 degrees Celsius above pre-industrial levels. A world of 1.5 degrees Celsius is almost unimaginable and must be avoided at all costs. 

Fortunately, a breakthrough climate model shows that we have a window to stay below the dangerous threshold of 1.5 degrees Celsius, achieving net-zero emissions before 2040. The two-year collaboration with 17 leading scientists, entitled Achieving the Paris Climate Agreement Goals (APCAG), shows that we can prevent the worst impacts of climate change with currently available solutions, unlocking trillions in economic benefits.

Foundations 20 (F20), in partnership with One Earth and the University of Technology Sydney, developed an Executive Briefing to condense the nearly 500 pages of scientific text into a high-level overview, entitled “Achieving the Paris Agreement Goals in the COVID-19 era.” Designed for professionals in the NGO and philanthropic sector, as well as business and governmental decision makers, the briefing provides a quick summary of the roadmap to achieve the ambitious 1.5°C goal.

In the 1.5C scenario, there are two main efforts required -- a rapid decarbonization of our energy system and large-scale land restoration -- which combined, provide a 66% likelihood of staying below 1.5 degrees Celsius.

For the global energy transition, electricity use will roughly double from today's levels by 2050, meeting a majority of our energy needs across all three major sectors -- Transportation, Industry, and Buildings & Infrastructure. Half of all transportation will be powered by electricity, with hydrogen and other renewable fuels replacing petroleum products. Industry will double its electricity use, meeting more than one-third of heating & process-energy requirements in addition to other renewable fuels. Buildings & infrastructure will also double electricity use, with more than one-third of heating needs met by geothermal, biomass, and solar heat sources. 

Coal will rapidly diminish, followed by a gradual phaseout of oil & gas, while renewables will expand from approximately 20% today to 100% in 2050. This is led by a rapid expansion of solar and wind power, which will meet 75% of electricity demand by 2050. Renewable fuels and energy efficiency will play a major role in reducing overall consumption, driven by smart-grid transmission, more efficient appliances, better transportation logistics, and other measures.

The transition to 100% renewable energy for all electricity and heating requires supplemental investments of $1.1 trillion per year, less than one-quarter of what governments currently spend on fossil fuels. 

Even with this rapid energy transition, staying below 1.5 degrees Celsius will require a major effort to protect and restore natural ecosystems -- the carbon sinks which keep our global climate system in balance. In addition to a rapid phaseout of carbon emissions from deforestation, the 1.5C scenario identifies a large potential for carbon dioxide removal through four restoration pathways.

Natural forest restoration, combined with reforestation on 350 million hectares of degraded land, alongside sustainable forestry practices, can deliver 480 billion tonnes of carbon dioxide removal by 2100. In the agriculture sector, reducing nitrogen and methane emissions, along with tree planting on croplands, can deliver the additional mitigation required to stay below 1.5 degrees Celsius.

The 1.5C transition model was developed using a sophisticated computer simulation of the world’s electrical grids — with 10 regional and 72 sub-regional energy grids modeled in hourly increments to the year 2050, along with a comprehensive assessment of available renewable resources like wind and solar, minerals required for manufacturing of components, energy efficiency measures, and configurations for meeting projected energy demand and electricity storage for all sectors through 2050. 

The revised APCAG 1.5C mitigation scenario limits global heating to 1.5°C using a carbon budget of 400 GtCO2 cumulative emissions commencing January 2020 per IPCC’s Sixth Assessment Report, Working Group 1 (AR6, 2021). The One Earth model calls for net zero emissions by 2040 achieved via: (1) a rapid reduction in fossil fuel emissions (black) approaching 100% renewable energy for all uses by 2050; and (2) approximately 500 GtCO2 of total carbon removal from reforestation and land restoration (gold) by 2100. Natural land carbon sinks (green) absorb CO2 but are likely to become a contributor of emissions in the second half of the century. Natural ocean carbon sinks (blue) continue absorbing CO2 through the century. Note: AR6 presents the 400 GtCO2 carbon budget as a “good” (67%) chance of limiting warming to 1.5°C, but this likely underestimates biosphere feedbacks, particularly from permafrost emissions, as well as anthropogenic emissions occurring between the pre-industrial era (1750–1800) and the early industrial era (1850–1900). For this reason, the OE model references the 400 GtCO2 budget as a “fair” (50%) chance of 1.5°C and calls for a steeper decline in emissions — net zero by 2040 instead of 2050 — with the goal of 1.4°C by 2100. Creative Commons: Karl Burkart, One Earth

All three sectors are increasingly electrified through 2050. Transportation moves from 2% electrification to 50%. Industry moves from 28% to 58%, with a large amount of heat/process demand met through electrified heat in 2050. Electrification of the Residential/Other sector moves from 33% to 64%, with nearly half of heating demand met by electricity. Note: Total energy demand is decreased through energy efficiency and demand reduction measures.

Global Electrification of the three major sectors -- transportation, industry, and buildings/other -- required to achieve the 1.5°C goal per Achieving the Paris Climate Agreement Goals (Teske, 2019). Mouse over the chart at 5-year increments to see data points for each transition. Credit: University of Southern California Marshall MS Business Analytics Program

Coal, Oil, and Gas are gradually phased out as electricity demand is met increasingly through renewable power generation, while fossil fuel-based liquid fuels are replaced by renewable fuels. Fossil fuels required for building heat and industrial processes are also phased out as renewable solar, geothermal, and other forms of renewable heat are ramped up. In 2050, approximately 59% of total final energy demand is met by renewable electricity.

Global Expansion of renewable energy delivery required to achieve the 1.5°C goal per Achieving the Paris Climate Agreement Goals (Teske, 2019). Lower curves show renewable electricity generation. Upper curves show renewable heating sources and renewable fuels. Mouse over the chart at 5-year increments to see data points for each transition. Credit: University of Southern California Marshall MS Business Analytics Program

View the F20 webinar with presentations by some of the experts involved in the climate model. Click on the images below to explore regional 1.5C energy transition pathways and land restoration potential divided in 10 global regions.