The relationship is pretty straight forward - more economic activities mean more CO2 emission. If economic growth is what primarily drives emission, then the bad news is that emission will continue to grow at the global scale since economy and its growth isn’t going anywhere.
Little bit of good news is that GDP is increasingly becoming efficient; for every $ GDP, there’s less and less emission observed over time for most countries. However, countries like China and India still needs to gain some efficiency, are way too inefficient compared to the global average.
Both high and low-income countries are doing better in terms of emission per unit economic activity, but middle-income countries are where a lot of emphasis needs to be given. The question is - is there a Kuznets Curve for CO2 emission? Good news is that - since 1990s efficiency is increasing, although it still isn’t at the level of 1960s.It is currently hovering around 1 kg CO2/$ GDP. Even doubling the efforts right now may take decades to get somewhere where developed countries are at the moment.
Region-wise, Latin America is the most consistent with <0.4 kg per $ GDP all along. EU and the US are being more efficient every year. Arab world and Asia need to do something radical and very soon.
Data Source: The World Bank, via R package “WDI” developed by Vincent Arel-Bundock, Plotting: ggplot2, R Markdown, dplyr