The 2015 Paris Agreement set out the goal to “hold the increase in the global average temperature to well below 2°C above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5°C above pre-industrial levels”.

The treaty has now been ratified by 195 nations.  The only countries that have not signed on are Iran, Libya, and Yemen.

Under the treaty, each country agrees to develop its own “nationally determined contributions” (NDCs) that spell out the nation’s commitments to cut greenhouse gas emissions.  Countries are expected to review and progressively revise their NDCs, at least every 5 years, reflecting their “highest possible ambition”.

But if each country is setting its own target, how do we know if they are adequate or not?  And how do we know if the combined commitments of all countries will achieve the global goal of keeping warming under 1.5˚C? 

The treaty itself plans for reports on progress, called “global stocktakes”, every 5 years beginning in 2023.  The first such stocktake is expected to be discussed and released this December at the next conference of parties meeting, COP 28, in Dubai.

Five years is a long time between report cards.  Fortunately, there are organizations that are independently keeping track of the global fight against climate change.

One such group is The Climate Action Tracker, often referred to by its acronym: CAT.  The CAT calls itself an independent scientific project that tracks government climate action and measures it against the Paris Agreement.

On a country-by-country basis, CAT evaluates climate change targets, policies, and actions.  It assigns ratings to countries, assessing whether their targets and policies are sufficient in light of the goals of the Paris Agreement and whether they are doing their fair share.

The notion of fair share is important because the treaty intends that developed nations, with greater resources and capacity,  should take on a greater share of the responsibility to cut global emissions.

The CAT does not report on all countries but those it does cover represent about 85% of global emissions and approximately 70% of the global population.  

CAT analysis brings clarity and transparency about global efforts to limit warming by:  

• assessing the fairness and sufficiency of national net zero emissions targets.
  
• forecasting expected global warming based on the combined national emission targets.

• forecasting expected global warming based on the actual combined policies and plans that countries have initiated to cut emissions.

Assessing target sufficiency

Targets are called nationally determined contributions because each nation on its own decides what its contribution to cutting emissions will be – there is no one to tell a country what it must do. 

The treaty says targets should represent “ambitious efforts” towards “achieving the purpose of this Agreement” and should “represent a progression over time”.  

Other than that, there is little guidance to countries on developing their targets. The agreement does not say what details an NDC should contain.  There is no mechanism to force a country to set an NDC by a certain date, nor are there any penalties for failing to achieve targets.  The agreement relies on peer pressure and naming and shaming to get countries to set meaningful goals.  

That’s why independent assessments of NDCs are so important. In their review, CAT applies ten criteria that evaluate the scope, transparency, and structure or architecture of a country target.

Under scope, it considers elements as basic as the target year (sooner is better), whether or not it covers the whole economy, whether it takes responsibility for shipping and aviation emissions that occur outside its borders, and whether it plans to reach targets itself or by co-operating with cuts in another nation.

The architecture criteria include whether targets are legally binding, if there is a credible process in place to review progress, and if there are details on how much of the target will be achieved by reducing emissions vs. removals by means such as reforestation or carbon capture.

The final category deals with transparency. Good targets have credible details such as plans on how they will be achieved as well as interim goals and specific timelines.   They should also explain why, in the country’s context, the target is ambitious and fair.  

Finally, if a country will rely significantly on carbon dioxide removals to achieve its target, as many do, it is important to detail the assumptions supporting those removal targets.  Carbon capture is a developing technology – a country’s plans to rely on it should be based on the latest scientific understanding about the capture and long-term storage of carbon.  A country’s plans should not rest on hopes that there will be a future breakthrough in technology that might not occur.

Taking stock of targets

The good news is that most of the major emitters around the world have set targets to reduce emissions.  195 nations have submitted NDCs as part of the Paris Agreement.

While not all countries have set targets to achieve net zero, most of the important ones have.  As of November 2022¹, countries that are targeting net zero represent 70% of the global population and 88% of global emissions.

The bad news is that there is a lot to be desired in the comprehensiveness of most national net-zero targets.  

According to CAT’s analysis, only six countries, representing 8% of global emissions have net zero targets that are considered “acceptable”.  CAT assesses 25 country targets as being “inadequate” and these represent 74% of global emissions.   

A target deemed “inadequate” lacks the details needed to assess its reasonableness.   and the national targets CAT assesses fall short for a variety of reasons.  The most common reasons are: failing to provide justifications of why a target is fair,  not detailing if net zero will be reached by reducing emissions or by removing CO2 from the atmosphere, and leaving out emissions from shipping and aviation outside of national borders.   

It is also concerning that only about 1/3 of the countries reviewed have their NDCs enshrined in law.  That means that they are more easily subject to repeals or changes when governments change.

Forecasted emissions gaps

Setting aside questions of credibility, if we add all the targets up, are they enough to keep warming below 1.5˚C?

Scientists have developed an emissions pathway that tells us how much CO2 equivalent emissions (CO2e) need to be reduced each year,  to stay on track to keep warming below 1.5˚C by mid-century.  

That pathway tells us that the world needs to cut CO2e emissions from the current ~50 gigatonnes (GtCO2e) per year to about 27 GtCO2e by 2030 – more or less by half.

CAT’s analysis of the global targets concludes that we are currently only aiming to reach 48 GtCO2e by 2030  – a small reduction vs. current levels.

If you’re a glass-half-full person, you can be happy that we are no longer expecting to increase emissions and by 2030 we expect to start cutting them slightly.  

The glass-half-empty perspective of course is that it is plainly obvious that the 2030 targets need to be halved to stay on track for 1.5˚C.    CAT concludes that the “Target Gap” to the 1.5˚C pathway is between 19 and 22 GtCO2e in 2030.

But targets are just intentions – actions are what actually cut emissions.  On the basis of actual policies and actions today, CAT concludes that the gap to staying on the 1.5˚C pathway is even greater.  The combined global policies and actions in place today will only ensure that emissions don’t grow.  The 2030 “Implementation Gap”  to stave off the worst impacts of climate change is in the range of 23 to 27 GtCO2e.

Implications for temperatures

The emissions gap analysis tells us we have to go further and faster in plans to stay on track to limit warming to less than 1.5˚C.

But what if we don’t succeed in doing so?  The other way to look at the data is to estimate what the warming will likely be by the end of the century if we don’t materially improve plans and targets to cut emissions further.

Working with the latest climate forecast models available, CAT publishes a set of global warming projections by 2100.  

According to CAT’s analysis, if nothing changes from today’s policies, actions, and plans, we can expect median warming to be about +2.7˚C vs. the pre-industrial average from 1850 -1900.  

The most credible set of national targets are those that spell out specific interim targets for 2030. If these are achieved, CAT forecasts that we can expect median warming to reach +2.4˚C by the end of the century.   

Forecast scenarios that take a very optimistic stance, assuming hitting less credible longer-term targets, pledges, and national aspirations, project median global warming to range between +1.8˚ and +2.0˚C – still above the 1.5˚C goal.

It may tempting to think that missing the 1.5˚C target by a degree or two will not be such a big deal – but it is.  Seemingly small increases in warming produce large consequences.  We live today in a world that has already warmed by +1.2˚C and we are increasingly besieged by fires, flooding, dangerous heat, and increasingly extreme weather events.  

A world that is more than +2˚C  warmer will be a very dangerous place.  The IPCC forecasts that at this level of warming, there will be significant impacts on the availability of water and food, with many regions facing water shortages and reduced crop yields. The frequency and intensity of extreme weather events would increase, leading to more frequent and severe droughts, floods, and storms. Sea levels would also continue to rise, threatening coastal communities. This is a world of mass migration, famine, climate refugees, political instability, and war.

Can we still win?

Given the slow progress so far, is it even possible to cut emissions sufficiently to keep warming below 1.5˚C?  A newly released study published in the journal Nature Climate Change, suggests that is it possible, but as time passes, it becomes more and more unlikely.  That is consistent with forecasts from the Intergovernmental Panel on Climate Change.

The COP 28 meeting in December 2023 is expected to include the first global stocktake of progress under the Paris Agreement.   Let’s hope that the conclusions from that review spur a much greater level of ambition and action from governments to get on track with the goals of the treaty. ■

1. CAT published global analyses on an annual basis – their next update is expected to be released in December 2023. County analysis and ratings are updated on an ongoing basis. ↩︎