The Carbon You Carry On

The Science, Simply

Global temperatures have risen by over 1.2°C since pre-industrial times — and in 2025, global average temperature reached 1.41°C above the pre-industrial baseline, making it the third consecutive year exceeding 1.4°C. That number sounds modest until you understand what it means in practice: warmer air holds more moisture, which intensifies rainfall and makes storms more ferocious. Here in the UK, October 2022 to March 2024 was the wettest 18-month period in England since Met Office records began over 180 years ago. The winter half-year of 2023–24 alone was the wettest on record for England and Wales in over 250 years, bringing devastating floods from Storms Babet, Ciarán, and Henk. Then 2025 swung to the opposite extreme — the UK's warmest and sunniest year on record, with the driest spring in over a century, four summer heatwaves, drought declarations across several regions, and a fourfold increase in wildfires compared with the previous year. Four of the UK's last five years now rank in the top five warmest since 1884, and every one of the top ten warmest years has occurred in the last two decades. The Met Office forecasts 2026 will extend this pattern, with global temperatures again likely exceeding 1.4°C. This is a pattern.

The greenhouse effect itself is not the villain — without it, the planet would be 33°C colder and life as we know it would not exist. The problem is that we have thickened the blanket. Carbon dioxide, responsible for roughly 75% of greenhouse gas emissions, can linger in the atmosphere for thousands of years. Methane, though it accounts for about 16% of emissions and persists for only 12–20 years, is at least 84 times more potent than CO₂ over a two-decade period.

What this means for us, practically: hotter temperatures bring heatwaves, wildfires, and droughts. Warmer air holds more water vapour, acting like a larger sponge that releases heavier, more torrential rain when it falls. The result is an intensifying cycle of extremes — longer dry spells followed by devastating floods. Rising sea levels compound the risk; UK levels have risen nearly 20 cm since 1900, with two-thirds of that increase occurring in just the last three decades.

The UK measures its greenhouse gas emissions through territorial estimates published by the Department for Energy Security and Net Zero. These track emissions produced within the UK's geographical borders, including business activities, land use, and the activities of residents and visitors. Notably, they currently exclude international aviation and shipping — a significant gap, and one that matters enormously for the travel industry.

The UK's warming stripes — each stripe represents one year's average temperature from 1850 to present. Blue is cooler, red is warmer. Credit: Professor Ed Hawkins, University of Reading.

Why Travellers Should Care

Travel is one of the great privileges of modern life. It broadens perspective, builds empathy, and creates the kind of transformative memories that shape who we become. But it also has a carbon cost that we cannot afford to ignore.

A landmark 2024 study published in Nature Communications found that tourism's global carbon footprint grew from 3.7 to 5.2 gigatonnes of CO₂ equivalent between 2009 and 2019 — an increase at 3.5% per year, more than double the rate of the wider global economy. Tourism now accounts for approximately 8–9% of the world's total greenhouse gas emissions. Without intervention, those emissions are projected to increase by 3–4% annually, doubling every 20 years.

Aviation sits at the heart of this challenge. It accounts for over half of tourism's direct emissions, and roughly 80% of aviation CO₂ is produced by flights exceeding 1,500 kilometres. The inequality is staggering: only about 11% of the global population flies in any given year, and just 1% of the world's population is responsible for more than half of all aviation emissions. Those of us who travel long-haul — particularly those of us who do so regularly — carry a disproportionate share of the burden.

And yet there is an encouraging counter-narrative. According to the World Travel & Tourism Council's 2025 Environmental & Social Research, the sector's greenhouse gas emissions in 2024 fell 9.3% compared with 2019, even as tourism's GDP footprint grew 6% beyond its pre-pandemic peak. Emissions intensity — emissions per unit of economic output — has dropped 15%. The sector is beginning to decouple growth from carbon, but we are nowhere near where we need to be.

The Real Impact of Tourism

When we think of tourism's carbon footprint, we tend to think of flights. But the full picture is far broader. The four main greenhouse gases at play are carbon dioxide (from fossil fuels, natural gas, and cement production), methane (from landfill, food waste, and cattle agriculture), nitrous oxide (from fertilisers and vehicle exhausts), and fluorinated gases (from refrigeration and air conditioning).

Tourism touches all of them. Consider the lifecycle of a single trip: the flight itself, the energy powering your hotel, the food transported to your plate, the vehicle transfers, the construction of the resort infrastructure, even the souvenirs you bring home. A recent Nature study found that air travel accounted for only about 12% of tourism's total carbon footprint when the full supply chain is considered — the remainder comes from accommodation energy use, road transport, food systems, and retail.

The destinations travellers love most are often the most vulnerable to the emissions their visits produce. Coastal communities face rising sea levels. Safari landscapes in East Africa experience intensifying drought cycles. Alpine environments see retreating glaciers. Island nations confront existential threats. There is a painful irony in the fact that the places we seek out for their beauty are being reshaped by the very act of our arrival.

Every Half Degree Matters

One of the most striking moments in the training was seeing the difference that a single half-degree of warming makes. The Paris Agreement set 1.5°C as the aspirational limit for good reason — the gap between 1.5°C and 2°C is not incremental. It is the difference between a difficult future and a devastating one. And 3°C — a scenario that remains plausible on current trajectories — is catastrophic.

For travellers who have dived the reefs of Zanzibar, watched elephants cross the Mara, or explored the coastlines of Brazil, these are not abstract statistics. They are the erasure of the very places we have been fortunate enough to witness.

The IPCC identifies four key risks for Europe alone at 3°C: deaths and heat stress increasing two- to three-fold compared with 1.5°C; substantive agricultural losses across most European areas that cannot be offset by gains in the north; over two-thirds of Southern Europe's population exposed to water scarcity; and flood damage costs and affected populations doubling.

When Heat Becomes Lethal

One concept from the training that has stayed with me is the wet-bulb temperature — a measure that combines heat and humidity to indicate the body's ability to cool itself through sweat. Human bodies rely on the evaporation of perspiration to regulate core temperature. Under high humidity, that mechanism fails. Once the wet-bulb temperature reaches 35°C, it becomes nearly impossible to cool down, especially if exercising or working outdoors. Temperatures approaching or exceeding this threshold have already been recorded near the India-Pakistan border, around the Persian Gulf, and near the Gulf of Mexico.

Think about what that means for the communities that host the world's travellers. Safari guides in East Africa spending hours in open vehicles. Market vendors in Southeast Asia. Farmers in India whose crops feed hotel kitchens. The people who make our travel experiences possible are among the most exposed to the lethal consequences of warming — and the least responsible for causing it.

The communities that make our travel experiences possible are among the most exposed to the consequences of warming.

The Uncomfortable Truth: Who Caused This, and Who Pays

This brings us to the climate justice dimension that, for me, sits at the heart of responsible travel. The IPCC defines climate vulnerability as the degree to which a system is susceptible to, and unable to cope with, the adverse effects of climate change. Crucially, that vulnerability is not just about geography. It sits at the intersection of three forces: economic vulnerability, geographic vulnerability, and political vulnerability. And it is driven by patterns of socio-economic development, unsustainable ocean and land use, marginalisation, and — the IPCC names this explicitly — historical and ongoing patterns of inequity such as colonialism.

That matters enormously for travel. Many of the destinations we are drawn to sit at the very centre of that Venn diagram. They are geographically exposed — coastal, tropical, arid. They are economically constrained — dependent on tourism revenue, with limited resources for adaptation infrastructure. And they are politically marginalised — underrepresented in the international forums where climate policy is decided.

The communities that contribute least to the climate crisis bear its greatest burden. The places we travel to for their unspoilt beauty, rich wildlife, and vibrant cultures are being fundamentally altered by emissions generated thousands of miles away, largely by the same wealthy nations whose citizens can afford to visit them. This is the uncomfortable truth at the centre of luxury travel, and pretending otherwise does a disservice to the destinations and people we claim to love.

The World Our Children Will Inherit

Perhaps the most confronting visual from the course came from Parents for Future UK: a series of hand-illustrated maps showing the challenges children alive today will face at 1.5°C, 2°C, and 3°C. At each threshold, the picture becomes more severe — longer droughts, more displacement, greater food insecurity, more disease, fewer species. At 3°C, the map shows a world where 150 million people have lost their homes, where crops fail, where one in six species is extinct, and where extreme weather has become relentless.

These are not projections for centuries from now. They are projections for the lifetimes of children already born. For those of us who design journeys to the world's most extraordinary landscapes, for those of us who take our families to experience wildlife and coastlines and cultures far from home, this is deeply personal. The world we are travelling through today is the world we are shaping for them.

What We Can Do: At Home

Carbon neutrality starts long before you pack a suitcase. The most impactful changes begin in our everyday lives, and they compound over time.

What We Can Do: When We Travel

This is where things get personal for me, and where I believe thoughtful travellers can make a genuine difference.

Know Your Numbers

Before you can reduce your travel emissions, you need to understand them. The average UK annual carbon footprint is 12.7 tonnes of CO₂e, and just over a quarter of that — 27% — comes from travel, with personal flights accounting for 9% of the total. If we are aiming to bring our individual footprints down to around 2.5 tonnes per year to stay within the 1.5°C budget, the carbon cost of flights alone uses up a significant portion of that allowance — and for long-haul or premium cabin travellers, it can consume the entire budget many times over.

There are several good tools for calculating your personal footprint. I would recommend trying more than one to get a rounded picture:

A Deeper Look at Carbon Offsetting

I want to be honest about offsetting, because it is a subject that deserves more nuance than it usually receives. Carbon offsetting — the process of funding projects that reduce or remove greenhouse gas emissions elsewhere to counterbalance your own — is not a silver bullet. Studies have shown that some offset programmes are associated with inflated impact measurements. Some are outright fraudulent. And there is a real risk that offsetting becomes a licence to continue emitting without making any meaningful changes to behaviour.

Tree-planting schemes, often the most visible form of offsetting, illustrate the problem well. To offset the full carbon footprint of someone living in the Global North, some estimates suggest 450 to 700 trees would need to be planted per person, per year. For flights alone, a single return from London to San Francisco would require roughly 16 trees per passenger. Scale that to Heathrow's 1,300 daily departures and you are looking at millions of trees every single day from just one airport. It is not physically possible, and poorly designed planting schemes can actually be counterproductive — clearing established old-growth forest to plant saplings destroys existing ecosystems and captures less carbon than the mature trees that were removed.

Other issues are well documented. Offset programmes may fund projects that would have happened regardless. Some impose changes on indigenous communities that are neither wanted nor beneficial. Historically, airline-integrated offset schemes have had take-up rates of just 1%. And many airline calculators measure emissions as though they were produced at ground level, when in reality fuel burnt at altitude has a significantly greater warming effect — a factor known as radiative forcing, which credible schemes account for with a multiplier of approximately 1.9.

What to Look for in a Carbon Offset Scheme

Not all offset providers are equal, and choosing well matters. There are four things I would look for:

At the time of writing, only Clear, Carbon Footprint, and IATA have successfully submitted their carbon offsets to be independently audited against the QAS. Both Clear (clear.eco) and Carbon Footprint (carbonfootprint.com) allow you to calculate and offset multiple flights, car journeys, and hotel stays as part of a single trip — and both also offer household carbon footprint offsetting. Clear additionally gives you the option to go beyond neutral and make your trip up to 200% carbon negative. You can check whether your airline's own scheme meets QAS standards at qasaudit.com.

The Case for Hopeful Action

It would be easy to read all of this and feel paralysed. But here is what my Carbon Literacy training reinforced above all else: this is not a problem beyond our reach. The very fact that emissions intensity in travel and tourism is declining — that the sector is generating more economic value while producing fewer emissions — is evidence that change is possible and already underway.

Travel, done well, is one of the most powerful forces for conservation that exists.

Travel, done well, is one of the most powerful forces for conservation that exists. Tourism revenue protects wilderness, funds anti-poaching operations, provides livelihoods that make communities stakeholders in the natural world rather than competitors with it. The lodges I recommend to my clients are not in spite of their environmental standards but because of them. The experience is better when the ecosystem around you is thriving, when the staff are from the local community and take pride in what they protect, when your presence genuinely contributes to something larger than your holiday.