A new study published May 2026 finds AI data center emissions are 30% higher than previously reported. Google, Microsoft, and Amazon are the largest contributors, the report notes.
Key facts
- Emissions 30% higher than reported.
- Study published in Nature Climate Change.
- Google, Microsoft, Amazon top emitters.
- Water usage 40% higher than disclosed.
- AI data centers account for 0.5% of global emissions.
The study, conducted by researchers at the University of California and published in Nature Climate Change, analyzed emissions from 2023 to 2025 across major hyperscalers. It found that official figures undercounted supply chain emissions and water usage by an average of 30% [According to the study].
The unique take: This isn't just a reporting error — it's a structural blind spot. Hyperscalers like Google and Microsoft have pledged carbon neutrality by 2030, but their disclosed numbers exclude the full lifecycle of hardware manufacturing and cooling water consumption. The study estimates that if all AI data center emissions were counted, they would account for 0.5% of global greenhouse gas emissions, up from the 0.3% typically cited.
Google, Microsoft, and Amazon — the three largest operators — have not yet commented on the study. The researchers used satellite data and public filings to cross-check corporate sustainability reports. They found that water usage for cooling alone was 40% higher than disclosed, driven by the high-density GPUs required for training large models like those from OpenAI and Anthropic.
The gap between reported and real
The study's lead author, Dr. Sarah Chen, told Mashable that "the gap between reported and real emissions is widening as AI workloads scale." She noted that current reporting frameworks, such as the Greenhouse Gas Protocol, allow companies to exclude Scope 3 emissions — those from suppliers and end-of-life disposal — which make up the bulk of the undercount.
For context: Google recently signed a 5 GW compute capacity deal with Anthropic, and Microsoft has committed to 10 GW by 2029. These agreements, while not directly criticized in the study, underscore the scale of the disconnect between capacity growth and emissions accounting.
What to watch
Watch for the Q3 2026 sustainability disclosures from Google, Microsoft, and Amazon. If they adjust their reported emissions upward by 30% or more, it would validate the study and force a re-evaluation of net-zero timelines. Also watch for regulatory action: the EU is expected to propose mandatory Scope 3 reporting for data centers by late 2026.
What to watch
Watch for Q3 2026 sustainability reports from Google, Microsoft, and Amazon. If they adjust emissions upward by 30%, it validates the study. Also watch the EU's proposed mandatory Scope 3 reporting for data centers by late 2026.
