The global community has coalesced around the ambitious goals of the Paris Agreement, one of which is to peak global greenhouse gas (GHG) emissions as soon as possible. The longer we delay the peak — the point when global emissions switch from increasing to decreasing — the more difficult it will be to limit global warming. Yet global GHG emissions are still rising and are expected to continue to climb through 2030.

The timing of when individual countries’ emissions peak and then decline — especially those of major emitters like the United States and China — is critically important in determining whether we can avoid the most dangerous climate impacts.

Although the timing of when global GHG emissions need to peak is well documented, there has been less research on when individual countries’ emissions have peaked. World Resources Institute’s (WRI) new paper, Turning Points: Trends in Countries Reaching Peak Greenhouse Gas Emissions Over Tim e, fills this gap by analysing which countries’ emissions peaked in the past and which countries have emissions- reduction commitments that imply peaking in the future.

The paper documents steady progress in the number of countries reaching peak emissions over time. By 1990, 19 countries had peaked (representing 21 per cent of global emissions), and by 2030 this number is likely to grow to 57 countries (representing 60 per cent of global emissions). Among the 57 countries that have peaked already or have a commitment that implies a peak by 2030 are some of the world’s biggest emitters, including China, the United States, Russia, Japan, Brazil, Germany and Mexico.

Peaking Progress by Decade

19 countries, representing 21 per cent of global emissions (based on 1990 emissions data), reached peak emissions in 1990 or earlier. Sixteen of them were former Soviet republics and/or economies in transition. The economic collapse after the break-up of the Soviet Union resulted in several former Soviet republics’ emissions declining sharply. Germany and Norway also peaked by 1990, and the European Union as a whole reached peak emissions by 1990.

By 2000

By 2000, 33 countries’ emissions peaked, representing 18 per cent of global emissions (based on 2000 emissions data). Many of the countries peaking in the 1990s were European nations such as the United Kingdom, France, the Netherlands, Belgium, Denmark, Sweden, Switzerland and Finland. Costa Rica also reached peak emissions levels in 1999.

By 2010

The number of countries that peaked by 2010 grew to 49, representing 36 per cent of global emissions (based on 2010 emissions data). This includes several more European countries such as Austria, Iceland, Ireland, Spain and Portugal, as well as Brazil (which peaked in 2004), Australia (which peaked in 2006), and the United States and Canada (both of which peaked in 2007).

By 2020

53 countries representing 40 per cent of global emissions (based on 2010 emissions data rather than 2020 projections) peaked or have a commitment to peak by 2020. Countries with commitments to peak as part of their Copenhagen Accord pledges for 2020 include Japan, the Republic of Korea, Malta, and New Zealand. By 2020, almost all developed countries are expected to have peaked. 42 of the 43 Annex I countries under the United Nations Framework Convention on Climate Change are expected to peak — all except for Turkey.

By 2030

China, the Marshall Islands, Mexico and Singapore have unconditional climate pledges under the Paris Agreement that imply a peak in emissions by 2030 (China’s commitment is for CO2 emissions only). This brings the number of countries that have peaked or have a commitment to peak by 2030 to 57, representing 60 per cent of global emissions (based on 2010 emissions data rather than 2030 projections).

To be conservative, our analysis only considers countries with unconditional targets as having a target that implies a future peak. Additional countries that have targets that imply an emissions peak by 2030 but are contingent on receiving international support include Bhutan, Botswana, Ethiopia, Grenada and South Africa. The inclusion of these countries would increase the per cent of global emissions covered by peaking countries from 60 to 61 per cent in 2030.

Accelerating Climate Commitments

While this trend is encouraging, it’s not enough. Research suggests that to have a likely chance of staying within the 2°C limit for the least cost, global GHG emissions need to peak by 2020 at the latest. The world’s ability to limit warming to 1.5 or 2˚C depends not only on the number of countries that have peaked over time, but also the global share of emissions represented by those countries; their emissions levels at peaking; the timing of peaking; and the rate of emissions reductions after peaking.

Countries must make and achieve commitments to peak their emissions as soon as possible, set their peaks at lower emissions levels, and commit to a significant rate of emissions decline after peaking.

Countries can make these commitments when communicating or updating their nationally determined contributions under the Paris Agreement in 2020. Doing so will help ensure that countries’ emission reduction commitments bring global emissions to the level needed to meet the Paris Agreement’s temperature goals, and avoid the most dangerous impacts of climate change.