Global emissions of CO₂ has the largest global warming potential, compared to all other greenhouse gasses, such as nitrous oxide, methane, and other fluorinated gases. For example, in 2015, 76% of GHG emissions in CO₂ equivalent/yr was just CO₂ (IPPC, 2018). In that year, an estimated 50.9 gigatonnes of CO₂ equivalent (GtCO2e) was emitted globally (World Bank, 2019).

According to this Vox article by Sigal Samuel, Kelsey Piper, and Dylan Matthews:

In most recent years (though not all of them), global carbon emissions have increased from the previous year. Saying there’s an 80 percent chance they’ll increase again, then, is a much more conservative prediction than it sounds. (This is called reference class forecasting, where you predict a statistic by looking at what prediction would have been correct in recent years or in other events like this one.)

Why are CO2 levels still increasing? Well, global population is still increasing (though more slowly than ever) and our efforts to decrease greenhouse gas emissions have been...lackluster, to say the least. Major polluters have made only token steps to reduce their emissions, and no country has cut their emissions as fast as the IPCC says that we need to. That’s a scary trend, and it makes me deeply unhappy. But I don’t see a lot of reason to expect it to change in 2020 — not with the same people in power across most of the world’s biggest emitters, and the same incentives for shortsighted climate policy around the world

Will global Global carbon emissions in 2020 be higher than they were in 2019?

This question resolves positively if preliminary estimates produced in the first half of 2021 indicate that global carbon emissions alone (not GHG emissions in CO2e) in 2020 was higher than emissions in 2019.