Do carbon offsets actually reduce emissions?

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1. 1

   Systematic assessment of the achieved emission reductions of carbon crediting projects.

   Nature communications (Probst et al.)Published Nov 14, 2024Checked Oct 4, 2026

   “Carbon markets play an important role in firms' and governments' climate strategies. Carbon crediting mechanisms allow project developers to earn carbon credits through mitigation projects. Several studies have raised concerns about environmental integrity, though a systematic evaluation is missing. We synthesized studies relying on experimental or rigorous observational methods, covering 14 studies on 2346 carbon mitigation projects and 51 studies investigating similar field interventions implemented without issuing carbon credits. The analysis covers one-fifth of the credit volume issued to date, almost 1 billion tons of CO2e. We estimate that less than 16% of the carbon credits issued to the investigated projects constitute real emission reductions, with 11% for cookstoves, 16% for SF6 destruction, 25% for avoided deforestation, 68% for HFC-23 abatement, and no statistically significant emission reductions from wind power and improved forest management projects. Carbon crediting mechanisms need to be reformed fundamentally to meaningfully contribute to climate change mitigation.”

2. 2

   Current Forest Carbon Offset Buffer Pool Contributions Do Not Adequately Insure Against Disturbance-Driven Carbon Losses.

   Global change biology (Anderegg et al.)Published Jun 1, 2025Checked Oct 4, 2026

   “Nature-based climate solutions in Earth's forests could strengthen the land carbon sink and contribute to climate mitigation, but must adequately account for climate risks to the durability of carbon storage. Forest carbon offset protocols use a "buffer pool" to insure against disturbance risks that may compromise durability. However, the extent to which current buffer pool tools and allocations align with current scientific data or models is not well understood. Here, we use a tropical forest stand biomass model and an extensive set of long-term tropical forest plots to test whether current buffer pool contributions are adequate to insure against observed disturbance regimes. We find that forest age and disturbance regime both influence necessary buffer pool sizes. In the majority of disturbance scenarios in a major carbon registry buffer pool tool, current buffer pools are substantially smaller than required by carbon cycle science. Buffer pool tools and estimates urgently need to be updated to accurately assess disturbance regimes and climate change impact on disturbances based on rigorous, open scientific datasets for nature-based climate solutions to succeed.”

3. 3

   Carbon offsets and credits (Wikipedia)

   WikipediaPublished Oct 1, 2026Checked Oct 4, 2026

   “A carbon credit is a tradable instrument (typically a virtual certificate) that conveys a claim to have avoided greenhouse gas (GHG) emissions or to have enhanced removal of GHG from the atmosphere. One carbon credit represents the avoided or enhanced removal of one metric ton of carbon dioxide or its carbon dioxide-equivalent (CO2e). Carbon offsetting is the practice of using carbon credits to offset or counter an entity's greenhouse gas inventory emissions in line with reporting programs or institutional emissions targets/goals. Carbon credit trading mechanisms (i.e., crediting programs), enable project developers to implement projects that mitigate GHGs and receive carbon credits which can be sold to interested buyers who may use the credits to claim they have offset their inventory GHG emissions. Similar to "offsetting", carbon credits that are permitted as compliance instruments within regulatory compliance markets (e.g., The European Union Emission Trading Scheme or the California Cap-n-Trade program) can be used by regulated entities to report lower emissions and achieve compliance status (with limitations around their use that vary by compliance program).”

4. 4

   Progress in the study of product methodology development and competitiveness assessment model of voluntary carbon offsets.

   Carbon balance and management (Han et al.)Published Mar 31, 2026Checked Oct 4, 2026

   “Through systematic literature review, it analyzes the development characteristics, application scenarios, and existing challenges of international mainstream standards (VCS, GS, CDM) and domestic CCER and carbon credit methodologies. Using Analytic Hierarchy Process (AHP) as the core framework, the research optimizes a competitiveness evaluation model covering environmental, social, and economic dimensions. A case study of eco-friendly home appliances is conducted for validation, followed by multi-directional comparisons with five existing models. Results indicate that international methodologies emphasize rigor and sustainability verification, while domestic approaches prioritize policy adaptability but face fragmentation challenges. The improved model demonstrates superior performance in environmental and social dimension evaluations compared to traditional models, offering enhanced comprehensiveness and specificity. This study provides scientific tools for methodological selection and competitiveness assessment of voluntary carbon reduction products, offering decision support for carbon market standardization and low-carbon economic transition.”