An Open Letter
to Humanity

This is not a warning. Warnings are what we received in 1992, when 1,700 scientists signed the World Scientists’ Warning to Humanity. This is a damage report. A field assessment of what we have done to the only planet we will ever have.

In 2024, our planet crossed

— breaching the threshold we promised we would not cross. It was the warmest year in the entire 175-year observational record.

Six of nine planetary boundaries are now breached. The systems that regulate our climate, our water cycles, our nitrogen flows, our biodiversity — all operating outside the safe zone that sustained civilisation for 10,000 years.

I. The Heat

Our oceans absorbed

of excess heat in 2025 alone — equivalent to 39 times all the energy humanity produced that year.

Our wildfires released

in the 2024–2025 season. Canada alone burned 15 million hectares in 2023 — nearly four times more carbon than global aviation.

II. The Ice

An ice-free Arctic summer could arrive as early as

. It is locked in regardless of what we do next.

Antarctic ice loss has

— from 48 billion tonnes per year in the 1980s to 202 billion tonnes per year in the 2010s.

Beneath the permafrost lies 1,500 gigatonnes of carbon — twice what is currently in the entire atmosphere. Four core climate tipping points trigger at 1.5°C. We are already at 1.55°C.

III. The Water

The fourth global coral bleaching event in 2023–2024 impacted

. 25% of all marine species depend on coral reefs for survival.

71% of global aquifers are in decline

. We are drawing down 324 billion cubic metres of freshwater more than is replenished every year.

We have created

in our oceans.

IV. The Living World

Since 1970, monitored wildlife populations have collapsed by

. Not a decline. A collapse.

37.7% of fish stocks are now overfished

— up from 10% in 1974.

In 2024, we lost another

of pristine rainforest.

V. The Soil Beneath Our Feet

75%

of Earth’s land surface became permanently drier in the last three decades. We are losing 24 to 75 billion tonnes of soil annually.

VI. How We Are Doing This

Fossil Fuels

Just

produced over 50% of global fossil CO₂ emissions in 2024.

The Things We Throw Away

The Great Pacific Garbage Patch contains

.

We generated

of electronic waste in 2022. Only 22.3% is recycled.

VII. Who Is Responsible

The richest 1% of humanity exhausted their fair share of the 1.5°C carbon budget in

.

The poorest 50% — responsible for 12% of emissions — are exposed to 74% of income losses from climate change. This is architecture.

VIII. What Is Still Possible

This letter is not a eulogy. Not yet.

Solar energy is now

than fossil alternatives. Battery storage costs have fallen

in a decade.

There are

filed across 55 jurisdictions.

The technology exists. The legal frameworks are emerging. Two trillion dollars was invested in clean energy in 2024. The solutions are deployed, proven, and cheaper.

And yet — current commitments target 52 to 58 gigatonnes in 2030. Keeping 1.5°C requires 25 to 30. We are aiming for double what the planet can absorb.