From Contrails to Cloud Formation – The New Tool That Could Transform Airline Carbon Disclosure

Aviation is one of the fastest-growing contributors to global greenhouse gas emissions, and concerns are mounting about whether current methods of calculating flight emissions truly capture the sector’s environmental impact.

Most of today’s carbon calculators rely on distance-based models that only measure carbon dioxide (CO₂). But this narrow focus overlooks powerful non-CO₂ effects, such as contrails, nitrogen oxides (NOX), and induced cloud formation—all of which intensify aviation’s warming footprint.

The omission of these factors risks underestimating aviation’s real climate impact, raising urgent questions for regulators, airlines, and passengers alike.

The Launch of ATP-DEC

In response to these concerns, Therme Group and the University of Surrey have developed the Air Travel Passenger Dynamic Emissions Calculator (ATP-DEC).

Unlike existing calculators, ATP-DEC incorporates life-cycle analysis (LCA) with real-world flight data to provide a more accurate, transparent, and comprehensive measurement of aviation emissions.

It accounts not only for fuel burn but also for aircraft production, airport infrastructure, baggage allocation, seating class differences, in-flight services, and non-Kyoto gases.

Why Current Calculators Fall Short

Existing aviation calculators, including those used by IATA, ICAO, Google TIM, and MyClimate, largely focus on CO₂ and total distance traveled.

This method ignores:

• Contrails and NOX emissions, which can trap heat and accelerate global warming.
• Diversions and route changes, such as Western airlines avoiding Russian airspace, which lengthen flight paths and increase emissions.
• Operational variations, like flight loads and seasonal impacts.

As a result, policymakers and passengers often receive incomplete or misleading data about the real climate cost of flying.

UK Aviation and Climate Policy

The challenge is especially pressing in the United Kingdom, where aviation currently accounts for nearly 7% of national emissions, projected to reach 9% by 2025 and 11% by 2030 as other sectors decarbonise.

The UK’s Climate Change Committee (CCC) has already warned that aviation could undermine the government’s Jet Zero strategy unless stronger measurement tools are adopted.

Meanwhile, the Civil Aviation Authority (CAA) has proposed that airlines may soon be required to disclose passengers’ carbon footprints at the time of booking, using standardised and accessible formats.

Scientific Recognition of ATP-DEC

The novelty of ATP-DEC’s methodology has earned recognition from the academic community.

The model has been peer-reviewed and will soon be published in Nature Communications Earth and Environment, ensuring global visibility and credibility.

Validated against 30,000 real-world flights, ATP-DEC achieved a mean absolute percentage error of just 0.5%, making it far more accurate than existing tools.

It also exceeds ISO 14083 standards by providing transparent, reproducible emissions breakdowns suitable for regulatory audits.

A Global Tool for Regulators and Airlines

ATP-DEC is not limited to the UK. Its methodology has global applicability, offering regulators, airlines, and passengers a transparent and harmonised system for measuring flight emissions.

For regulators, it provides a defensible foundation for audits and disclosures. For airlines, it allows for more trustworthy carbon reporting. For passengers, it ensures clear and accurate emissions data when booking flights.

The Role of Carbon Tokenomics (CTM)

Alongside ATP-DEC, Therme Group has developed the Carbon Tokenomics Model (CTM)—a blockchain-based financing system designed to channel passengers’ micro-investments into green projects, including sustainable aviation fuel (SAF) production.

Together, ATP-DEC and CTM offer a scalable, transparent framework for aviation’s global decarbonisation.

Global Push for Sustainable Aviation Fuel (SAF)

Worldwide, governments are increasingly turning to SAF as the key to aviation’s future.

• The United States ties clean-fuel tax credits to verifiable emission reductions.
• Singapore will begin levying passengers in 2026 to co-fund SAF blending.
• Japan has launched domestic SAF production to reach a 10% SAF target by 2030.

ATP-DEC provides the scientific framework to measure SAF’s real impact, while CTM offers the financial model to scale production globally.

Why This Matters Now

With aviation emissions projected to rise further, credible carbon disclosure is essential. Public and political pressure on airlines is intensifying, and without reliable tools, efforts to decarbonise aviation risk stalling.

ATP-DEC represents a step change in how emissions are measured, ensuring that airlines, regulators, and passengers all work with accurate and accountable data.

FAQs

Q1: What is ATP-DEC and who developed it?
ATP-DEC stands for Air Travel Passenger Dynamic Emissions Calculator. It was developed by Therme Group and the University of Surrey to provide more accurate flight emissions data.

Q2: How does ATP-DEC differ from existing carbon calculators?
Unlike traditional calculators that focus only on CO₂ and distance, ATP-DEC includes non-CO₂ effects, life-cycle analysis, real flight paths, baggage allocation, and seating class impacts.

Q3: Why are non-CO₂ effects like contrails important?
Contrails, NOX emissions, and induced cloud formation significantly intensify aviation’s warming effect, but are often excluded from existing tools, leading to underreported emissions.

Q4: How accurate is ATP-DEC?
The model was validated against 30,000 flights and achieved a 0.5% error rate, making it one of the most accurate tools available.

Q5: How does ATP-DEC support global aviation decarbonisation?
It provides a transparent, reproducible framework for emissions reporting worldwide. Combined with Carbon Tokenomics financing, it can help scale sustainable aviation fuel (SAF) adoption globally.