Definition 1
1.5C Aligned means that the level of ambition of [the organisation's] targets to reduce GHG Emissions and its Climate Change Mitigation Measures are consistent with achieving the goal in Article 2.1(a) of the Paris Agreement to pursue efforts to limit the global temperature increase to 1.5 Celsius above pre-industrial levels with little to no overshoot
Definition 2
1.5C Aligned means that [the organisation's] targets to reduce GHG Emissions and Climate Change Mitigation Measures are aligned with scenarios that yield a long-term global warming outcome of 1.5 Celsius above pre-industrial levels [with [60 (sixty) percent] probability and [no OR less than 0.1 percent] overshoot].
Drafting notes and guidance
1.5 Celsius (1.5C) aligned targets are the most common choice for businesses. They represented 66 (sixty-six) percent of all submissions to the Science Based Targets initiative ( SBTi ) in 2021.
Global scale
The Paris Agreement requires countries to pursue efforts to limit the increase in global temperature to 1.5C. To achieve this, contract parties need to ensure that their climate targets and mitigation measures align with pathways that predict a global temperature increase of a maximum of 1.5C by 2100, with little to no overshoot. The 'pathways' referred to here are, for example, the pathways examined by the Intergovernmental Panel for Climate Change ( IPCC ).
A climate target will be 1.5C aligned if the company setting the target is able to rapidly reduce its emissions in a manner that meets eligible 1.5C pathways. Contract parties may want to consider using standards where an independent body will verify that their targets are 1.5C aligned. An example is the SBTi Net-Zero Standard.
Little to no overshoot
There are pathways that achieve the 1.5C goal by 2100 by exceeding this temperature first (over 0.1 percent) and then reaching 1.5C in 2100. This occurs if emissions reductions are delayed and removals are relied upon later. The IPCC Special Report on 1.5C shows that the risks of a high overshoot on natural and human systems are immense and potentially long-lasting and irreversible. As such, contract parties should only consider pathways that achieve 1.5C by 2100 that have no or little overshoot.
1.5C aligned or Paris aligned?
This definition is very similar to TCLP's glossary term Paris Aligned. While these terms are often used interchangeably, there are clear distinctions between the two.
TCLP glossary term Paris Aligned refers to the 3 (three) goals in Articles 2.1 and 4.1 of the Paris Agreement:
- temperature goal;
- adaptation and mitigation goal; and
- financial flow goal.
The goals are also known as the climate objectives.
Article 2(1)(a) contains 2 (two) temperature goals:
- holding the increase in global average temperature to well below 2C; and
- pursuing efforts to limit that increase to 1.5C.
By contrast, 1.5C Aligned refers only to the second temperature goal in Article 2(1)(a).
To be unambiguous about which temperature goal in the Paris Agreement the parties are aligning their targets and climate change mitigation measures to, TCLP recommends using 1.5C Aligned rather than Paris Aligned.
Option 2
This definition is aligned with the Race to Zero Lexicon.