We periodically update En-ROADS to improve the modeling and reflect the latest historical data. In the November 2025 update, the global net greenhouse gas emissions trajectory in the Baseline Scenario changed slightly due to improved modeling of electrification and its effects on energy demand from renewables and fossil fuels. The “Greenhouse Gas Net Emissions” graph reflects the combined effects of many sources, each with its own dynamics—some increasing, others decreasing.
The key trends causing this behavior are:
Population: Global population grows until about 2085, but more and more slowly, especially after 2040.
Energy use: GDP grows faster over time, but the energy intensity of GDP is falling. Energy use rises throughout the century.
Land use: As population growth slows, food demand grows more slowly too. Land for farming expands at a decreasing rate, so deforestation slows and net land-use emissions peak around 2050.
Agriculture: We keep getting more efficient at producing food, with less methane and nitrous oxide released from animal digestion, manure, and fertilizer per unit of food.
Waste: Slower population growth plus improving waste management practices lead emissions from wastewater and landfills to peak around 2075.
Fossil fuels: Efficiency improvements, electrification, and renewables all slow fossil fuel growth. Oil and natural gas peak by 2035. Coal declines until around 2050, then begins to grow again as electricity demand increases faster than renewable energy expands, and coal remains a lower-cost option than natural gas in the Baseline Scenario.
Overall, these combined trends lead to emissions that remain approximately constant after 2030 in the Baseline Scenario. This shape may change in future updates as new data or emerging trends are incorporated. It’s important to note that the Baseline Scenario is not a prediction, but rather a reference point for evaluating policy choices.