Our Mission

The real climate
impact of aviation

Making aviation's hidden climate impact visible and actionable.

Aviation's total climate impact goes beyond CO₂. Non-CO₂ effects like contrails contribute the majority of aviation's warming.

~2–4xtotal impact
vs CO₂ alone

~35%

of aviation's total warming from contrails

CO₂

~65%

from CO₂ emissions

How Contrails Warm the Planet

A hidden multiplier

The Invisible Problem

When you book a flight, you might see a carbon offset option. But CO₂ is only part of the story.

Condensation trails — contrails — form when hot, humid engine exhaust meets cold air at cruise altitude. In the right atmospheric conditions, these thin ice-crystal clouds persist for hours, trapping outgoing heat radiation like a blanket.

Research from institutions including MIT, DLR, and Imperial College London estimates that contrails cause approximately 35%of aviation's total climate warming effect. For some flights, the contrail impact alone can be 2–4x greater than the CO₂ emitted.

See the Science Behind It

Radiative Forcing

Solar vs. thermal radiation

Contrails interact with both incoming solar radiation (cooling effect during daytime) and outgoing thermal radiation (warming effect at all times). At night, the net effect is almost always warming.

SkyPrint calculates the energy forcing in Watts per square meter (W/m²) for each flight segment.

The Science

Schmidt-Appleman Criterion (SAC)

Contrails form when the mixing of hot exhaust with ambient air passes through liquid water saturation. The SAC predicts whether this threshold is crossed based on temperature, pressure, and humidity at cruise altitude. If the surrounding air is also ice-supersaturated, the contrail persists.

Inputs

Temperature Pressure Humidity

Predicts

Contrail Formation

Outcome

Persistent Contrail

The Science

CoCiP (Contrail Cirrus Prediction)

Developed by DLR and extended by Breakthrough Energy, CoCiP models the full lifecycle of a contrail — formation, spreading, and dissipation — computing the net energy forcing (warming or cooling) over its lifetime. SkyPrint uses CoCiP via the open-source PyContrails library.

Models

Lifecycle

Computes

Energy Forcing (W/m²)

Outputs

Net Warming or Cooling

What You Can Do

Most contrail warming comes from a small fraction of flights flying through ice-supersaturated air. Modest altitude changes (1,000–2,000 ft) can avoid these regions with minimal fuel penalty — typically under 2% additional fuel burn.

Contrail-aware flight planning represents one of the most cost-effective climate interventions available to aviation today.