Greenhouse Gas Emissions Rose Last Year. Here Are the Top 5 Reasons.

WASHINGTON — If the world wants to avoid drastic global warming this century, we’ll need to reduce our greenhouse gas emissions sharply in the years ahead.

For now, however, we’re still moving in the opposite direction: Carbon dioxide emissions from the use of coal, oil and natural gas increased 1.4 percent globally in 2017 after holding steady for the previous three years, the International Energy Agency reported on Thursday. That’s the equivalent of adding 170 million new cars to the road worldwide.

The energy agency, which called the findings “a strong warning for global efforts to combat climate change,” detailed several big reasons CO₂ emissions are increasing again. Here’s a look at the main ones:

Emissions are rising fastest in Asia

Renewable energy is growing fast, but not fast enough

Coal made a small comeback

S.U.V. sales keep booming

Energy efficiency efforts are slowing