Fossil fuel CO2 dipped this year, but land-use emissions rose to 5.1 billion tons, and scientists say the bigger test for the climate comes in 2027

Fires burning through drained peatlands and degraded forests in Southeast Asia are the main reason total carbon dioxide emissions are projected to hit a record 43.3 billion metric tons in 2026, even as emissions from fossil fuels dip. The finding comes from the 2026 Global Carbon Budget, released Nov. 10 by more than 140 scientists, which projects land-use emissions rising to 5.1 billion metric tons this year, according to ScienceDaily's summary of the report.

The report ties that rise to peat fires, almost entirely ignited by people, and to forest degradation, both made worse by drier conditions as a strong El Niño developed. Total emissions were 42.8 billion metric tons in 2025.

The same El Niño now threatens the other side of the carbon ledger — the forests, soils and oceans that soak up CO2. Forests and soils recovered their ability to absorb CO2 after the 2023 to 2024 El Niño, but scientists expect the powerful 2026 event to dent that natural sink again in the coming year, which could speed the buildup of CO2 in the atmosphere.

Peat Fires and Forest Loss Reverse a Decade of Progress

Land-use emissions had been falling for years, thanks largely to slower deforestation in Brazil and Indonesia and to tree planting in China. That makes the projected 2026 rise to 5.1 billion tons a notable reversal — and one driven largely by a single region.

Peatlands are swamp soils packed with thousands of years of partly decayed plant matter. When they are drained for plantations and then dry out during El Niño, they burn slowly and release enormous amounts of stored carbon, along with thick smoke. The report says the 2026 increase came from these fires and from forest degradation in Southeast Asia, according to the Global Carbon Project.

Over 2016 to 2025, deforestation released about 3.8 billion tons of CO2 a year on average, with reforestation and new forests offsetting roughly half of that. Brazil, Indonesia and the Democratic Republic of the Congo have historically accounted for most land-use emissions.

Land-use estimates carry far larger uncertainty than fossil fuel figures, because they rely on satellite fire data, forest models and incomplete national reporting. The direction of change is clear, but the exact size of this year's increase may be revised.

A Smaller Fossil Dip Driven Partly by an Oil Shock

Nature World News previously reported on the fossil fuel side of the budget, which shows global fossil CO2 falling 0.4 percent to 38.2 billion tons. Oil emissions are projected to drop 1.9 percent, partly because of the energy shock tied to the Iran conflict, while coal edges up 0.6 percent.

The country picture is mixed. China, responsible for about 32 percent of fossil emissions, is projected to fall 0.9 percent. The United States is projected to drop 1.3 percent, mainly from lower coal use, and the European Union 1.5 percent. India is projected to rise 4.4 percent, faster than its 10-year average.

Clean energy is doing real work. Solar, wind and electric vehicles are now meeting roughly two-thirds of new energy demand, and solar and wind are projected to avoid about 4.6 billion tons of CO2 in 2026, up from 0.28 billion tons in 2010.

Glen Peters of the CICERO Center for International Climate Research put the dip in context. "A drop in emissions in one year is not a peak," he said, adding that a true peak requires structural change, according to the report summary.

Weakened Sinks Could Speed CO2 Buildup in 2027

Land and ocean ecosystems absorb roughly half of human CO2 emissions each year, acting as a natural brake on warming. During El Niño years, heat and drought in the tropics reduce how much carbon plants take up, and fires release more.

Patrick McGuire, a land modeling scientist at the University of Reading who contributed to the budget, said forests and soils have absorbed more carbon since the last El Niño. "The large El Niño now developing is expected to dent it again next year," he said in a University of Reading statement. He added that climate change has already cut global land uptake by almost a fifth over the past decade.

Atmospheric CO2 is projected to average 427.7 parts per million in 2026, about 54 percent above pre-industrial levels. The remaining budget for limiting warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit) is about 150 billion tons of CO2, less than four years of current emissions.

The report does not attribute any single weather event to climate change. Its sink projection for 2027 is a model-based expectation, not a measurement, and the scale of the El Niño effect will depend on how long and how strongly the event persists.

Haze Health, Fire Seasons and Household Costs

For people in Indonesia, Malaysia and Singapore, peat fires mean seasonal haze that can push air quality to unhealthy levels and keep children indoors. For readers in the United States, the connection is less direct but still real: a weaker global carbon sink means more of each year's emissions stays in the air, adding to long-term warming that shapes heat waves, wildfire seasons and insurance costs.

The policy lesson is that forest and peatland protection matters alongside clean energy. Julia Pongratz of LMU Munich said in the report summary that scaling up carbon removal is also needed, though novel removal methods currently offset less than 30 minutes of annual fossil emissions.

The next updates will come from the full peer-reviewed Global Carbon Budget paper and from NOAA's monthly CO2 measurements at Mauna Loa, which will show whether the El Niño sink weakening appears in 2027 as projected. The bottom line: a fossil dip is welcome, but the land, not the smokestack, decided this year's record.

What Readers Want to Know

Why are total CO2 emissions at a record if fossil emissions fell? Land-use emissions rose to a projected 5.1 billion tons, more than offsetting the 0.4 percent fossil dip.

What caused the land-use increase? Peat fires, almost all started by people, and forest degradation in Southeast Asia, worsened by El Niño drought.

What is a carbon sink? Forests, soils, and oceans that absorb CO2. Together they take up roughly half of human emissions each year.

How could El Niño affect sinks? Heat and drought reduce plant uptake and increase fires. Scientists expect the 2026 El Niño to weaken the land sink in 2027.

Has the world reached peak emissions? Not yet. Scientists say one year's decline is not a peak unless driven by lasting structural change.

How much carbon budget is left for 1.5°C? About 150 billion tons of CO2, under four years at current rates.