An overview of carbon markets 

03 February 2025

As global emissions and temperatures continue to rise, scaling high-integrity carbon markets are crucial for establishing carbon pricing for economic activities and financing climate solutions.

While private and public sector initiatives to reduce emissions have made progress, current climate actions and policies put the planet on a path to well above 2°C of warming by the end of the century[1] breaching the goals of the Paris Agreement.

Part of the problem is not putting an economic cost on emissions to create appropriate considerations for negative externalities in economic growth.  The true costs of emissions are not reflected in economic activities, which has led to unintended consequences in the form of environmental degradation. 

The purpose of carbon markets is to help reduce emissions by trading carbon credits and putting a direct price on carbon. There are two types of carbon markets — compliance carbon markets (CCMs), also known as Emissions Trading Systems (ETS), which trade carbon permits/allowances for compliance with regulatory emissions limits, and voluntary carbon markets (VCMs), which trade carbon credits used to voluntarily offset emissions.

Ultimately, carbon markets exist to price the cost of carbon to the economy, to incentivize emissions-intensive industries to decarbonize and/or finance solutions to support climate goals. The verdict is still out on whether the markets have been effective in achieving these goals.

Key takeaways    

This paper discusses two types of carbon markets — CCMs and VCMs. While they both aim to price carbon and reduce emissions, VCMs are much smaller, more dynamic and face significant challenges with respect to the integrity of claims and scale.

Despite their respective challenges, both CCMs and VCMs are expected to grow as emissions regulations tighten to align with global climate goals and companies look to meet their decarbonization targets across all sectors. As such, carbon credit demand will be driven by companies looking to meet their voluntary mitigation decarbonization targets as well as regulated entities seeking eligible credits to comply with regulatory emissions obligations (such as ETS or carbon tax). There may be tangible investment opportunities in building the supply of high-integrity credits.

While the opportunity set is growing across asset classes, investor participation has been limited due to the complexity, fragmentation and volatility of these evolving carbon markets. In particular, VCMs have faced increased scrutiny in recent years due to a lack of standardization and projects failing to deliver promised outcomes. There is strong support from policymakers and market participants to scale and ensure integrity in carbon markets, which are considered crucial policy and financing tools for achieving climate transition goals.

The role of carbon markets in investor climate transition plans is currently unclear. While investor participation in CCMs can drive liquidity and price discovery, it does not have a direct effect on reducing atmospheric carbon emissions. VCMs can have a more direct impact through high-integrity carbon credits which finance measurable emissions reduction and removal projects. Nonetheless, the use of credits as an offset should be a last resort reserved for hard-to-abate emissions. Currently, investor net-zero frameworks and the Science Based Targets initiative (SBTi) do not encourage the use of offsets in target-setting.

An overview of carbon markets

In our paper, we explore how investors can participate in carbon markets and what the potential opportunities and risks are.

About the author(s)
Lovey Sidhu

Sustainable Investment Specialist, Mercer Global Strategic Research

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