A new International Energy Agency report finds that worldwide carbon dioxide emissions from energy — which are the lion's share of global emissions — ticked upward by 1.4% in 2017 after a three-year plateau.

Why it matters: The findings underscore the immense challenge of reigning in heat-trapping emissions in an increasingly energy-hungry world. Carbon dioxide output is on pace to eventually bring about global warming levels that blow past the targets of the Paris climate agreement.

What's happening now: Emissions rose despite the expansion of solar and wind power, and displacement of coal by natural gas and renewables in some markets.

"The increase in carbon emissions, equivalent to the emissions of 170 million additional cars, was the result of robust global economic growth of 3.7%, lower fossil-fuel prices and weaker energy efficiency efforts," the report states.

The big picture: The agency estimates that global energy demand increased by 2.1% last year, well above by the 2016 rate, with 40% of that growth coming from China and India alone.

Fossil fuels met over two-thirds of that additional worldwide energy need.

Demand for coal, the most carbon-intensive fuel, rose by about 1% after two years of declines. However, renewables, natural gas, nuclear and oil all grew more robustly.

The context: The IEA data is the second major report to show that the multi-year hiatus in emissions increases has ended. A recent study called Global Carbon Budget reached a similar conclusion, finding that global emissions from fossil fuels and industry grew by 1.5% last year.

Quoted: "The significant growth in global energy-related carbon dioxide emissions in 2017 tells us that current efforts to combat climate change are far from sufficient," IEA head Fatih Birol said in a statement.

Asian nations provided the bulk of the emissions growth, while some major countries including the U.S., U.K., Mexico and Japan saw declines, IEA said.

Yes, but: The report nonetheless shows how the global economy is becoming less carbon-intensive. The economy in China, by far the world's largest emitter, grew by almost 7% last year but it's emissions grew by just 1.7% "thanks to continued renewables deployment and faster coal-to-gas switching," IEA said.