From Paris Climate Agreement 2015 to Paris Air Show 2025: Decade of Climate Crashes

Dream of slowing climate changes in flames with false promises, missed commitments

Last week as global aviation executives gathered in Paris for the bi-annual Paris Air Show, while sustainability was on every lip at Le Bourget airport, most did not have a lot to show for what they had done in the decade since global community reached a so-called historic agreement in Paris a decade earlier, to save the world from climate change, with the Paris Climate Agreement. A decade on, almost on every single count, the world as a whole is completely out of step with what is needed and what was indeed promised at the same grounds of Le Bourget in December 2015.

The champagne flutes have barely been cleared from the chalets at Le Bourget. The roar of the latest fighter jets and sleek airliners still echoes in the memories of attendees. The Paris Air Show 2025, aviation’s glittering biennial showcase, concluded with the usual fanfare celebrating human ingenuity and global connection. Yet, this year’s spectacle unfolded under a starkly different shadow, the looming 10th anniversary of the Paris Climate Agreement, signed at the same hallowed grounds of Le Bourget in December 2015.

The dissonance is deafening. While the world pledged to hold global warming “well below 2°C,” the aviation industry, basking in its post-pandemic resurgence, has been taking the world on an accelerated flight towards a climate crash.

The Soaring Contradiction: Growth versus goals

In 2015, aviation accounted for roughly 2-3 pc of global carbon dioxide (CO₂) emissions. A significant, but seemingly manageable, slice of the pie. The optimism of Paris suggested technology and cooperation could tame this sector. A decade on, the reality is starkly different.

Despite efficiency gains, total aviation CO₂ emissions have surged. Pre-pandemic levels were breached rapidly. In 2024, emissions were estimated to be over 20 pc higher than in 2015. Air travel demand is booming, particularly in Asia, and air cargo remains the lifeblood of global commerce.

The industry, via the International Air Transport Association (IATA), committed to NetZero Carbon by 2050. However, projections paint a daunting picture. Without drastic intervention, aviation emissions could double or even triple by 2050 compared to 2019 levels. Reaching net-zero from that peak, while demand continues to grow, requires a revolution, not incremental change.

By focussing solely on aircraft exhaust vastly underestimates aviation’s footprint since global airports serve as gigantic carbon hubs, with their massive terminals, sprawling runways, energy-intensive lighting, heating, cooling and ground operations make airports significant emitters. While some aim for ‘NetZero airport operations’, this often excludes the core activity or the planes themselves.

Another aspect that the aviation industry has tried to cover up is the Scope 3 emissions, which are those emissions with a direct link to the industry, but where industry itself is not the emitter.This is aviation’s dirty secret, often omitted from industry reports, such as passenger ground transport as billions of journeys are undertaken by car, taxis, and buses ferrying people to and from airports daily. Similarly, the trucks and vans transporting goods to consolidation centres and final destinations, which again are omitted and the in-flight footprint as vast quantities of single-use plastics, such as cups, cutlery and packaging, food production and waste, which are often high-emission meats and dairy, duty-free goods and printed materials.

Beyond the civil aviation, military flights, largely excluded from international climate agreements and reporting, contribute significantly to global aviation emissions but operate with near-zero public scrutiny or pressure.

A Decade of Delay: The lagging green transition

Air Shows around the world buzz with promises of a sustainable future such as hydrogen concepts, electric vertical take-off vehicles (eVTOLs), and Sustainable Aviation Fuel (SAF) logos emblazoned everywhere. Yet, the pace of tangible progress has been glacial.

SAF is the industry’s primary near-term hope. However, current global production meets less than 0.2 pc of total jet fuel demand and scaling up faces immense hurdles due to high costs, which are 3-5 times that of conventional fuel, limited sustainable feedstocks which are those that avoid competition with food crops or lead to deforestation, and lagging policy support for production. While airlines announce SAF offtake agreements, they represent tiny fractions of their overall consumption. The 2025 Air Show saw more SAF pledges, but few concrete breakthroughs on scaling production.

Similarly, the aviation industry’s promises for a technological change to go sustainable through new modes of powering aircraft have so far remained pipedreams. Certainly, hydrogen and battery-electric propulsion hold promise, but primarily for smaller, shorter-range aircraft decades from mainstream adoption. Wide-body, long-haul flights, the biggest emitters, will rely on liquid fuels for the foreseeable future. Efficiency improvements in conventional engines are incremental, easily outpaced by traffic growth.

The industry is also facing an infrastructure inertia as retrofitting airports for widespread SAF use, hydrogen storage, or electric charging requires massive investment and planning and is lagging far behind the rhetoric.

Another challenge is a lack of cohesive policy. A global carbon pricing mechanism for aviation (like CORSIA) remains weak, complex, and riddled with loopholes. Kerosene tax exemptions persist in most countries, a massive implicit subsidy for fossil fuels and regulations on non-CO₂ effects (contrails) are nascent.

Shared responsibility for a sky-high problem

Achieving anything close to aviation NetZero by 2050 demands action far beyond aircraft manufacturers:

The industry in its entirety, with airlines, manufacturers and airports, must move beyond lip service and PR. This means a massive and accelerated investment in SAF production by aggressively funding production facilities and accepting higher fuel costs in the short term.

Airlines also need to accelerate retirement of older, inefficient aircraft, even if financially painful. They must also seek operational optimisation by investing in AI for flight path optimisation, such as  reducing contrails, single-engine taxiing, weight reduction.

The industry must also adopt transparent full-scope reporting with  mandatory accounting and reduction targets for Scope 3 emissions and revolutionising the passenger experience by drastically reducing single-use plastics, offering genuinely sustainable food options by default, enabling seamless low-carbon ground transport links.

Passengers:

Not just the airlines or the aviation industry, but the passengers must also play their part in combatting carbon emissions. Frequent flyers, who are less than 20 pc of the population, but cause 80 pc of passenger emissions, must confront their impact. They can opt to fly lesser by choosing rail for short-haul, embracing virtual meetings, taking fewer but longer trips. They can also fly smarter by opting for

newer, more efficient aircraft types, where possible, and preferring airlines with strong SAF commitments, as well as direct flights and of course by packing light.

Passengers also need to scrutinise offsets to which they contribute, often because they were egged on by the airline. But offsets are not a get-out-of-jail-free card; they must be high-quality, permanent, and additional and used by airlines after they have achieved significant emission reductions.

For their part, cargo shippers and recipients must integrate aviation emissions into their own supply chain carbon accounting and actively seek lower-carbon logistics options through consolidation, slower shipping modes where feasible, demanding transparency and action from freight carriers.

The governments, of course, have the biggest role and responsibility in getting the airlines and the aviation industry to keep their commitments. They must stop coddling the industry and need to end fossil fuel subsidies by imposing a tax on kerosene, which fuels conventional aircraft today.

The governments should also strengthen regulations and mandate increasing SAF blending ratios, enforce strict efficiency standards, regulate non-CO₂ emissions.

They can also fund research and development and creation of modern infrastructure as substantial public investment in SAF, hydrogen, and electric aviation infrastructure is crucial.

The governments also need to integrate defence in sustainability by adding military aviation in national emission inventories and set up their reduction plans. For this, defence aviation must be brought into the climate fold, subject to transparency and ambitious decarbonisation targets.

Carbon credits and farmers: A lifeline or a distraction?

The aviation industry heavily promotes carbon offsetting and carbon credits as part of its net-zero pathway. Purchasing credits from projects like reforestation or soil carbon sequestration on farms is attractive as it allows for continued fossil fuel use while claiming NetZero emissions. However, this is fraught with peril as offsets are not a substitute. Offsets must be supplementary to deep, direct emission cuts within aviation itself. Relying on them excessively is greenwashing.

They also need to look at issues of permanence and leakage by seeing whether the carbon stored in trees or soils truly stay locked away for centuries and if preventing deforestation in one area just pushes it elsewhere.

There is also an urgent need for ensuring the integrity, additionality or the issue that the project being sought to cover with offsets would happen anyway, and accurate measurement of carbon credits remains difficult and controversial.

While high-integrity carbon removal credits will be necessary to counterbalance aviation’s hardest-to-abate emissions, they are not the answer. They are a potential component of a solution predicated on the industry slashing its direct emissions by 70-80 pc or more through technology, efficiency and SAF.

Missing the landing strip of NetZero by miles

he honest answer to the question whether the aviation industry will actually meet its stated goal of NetZero by 2050, based on the trajectory of the past decade, is highly doubtful. The scale of transformation required is unprecedented. The relentless growth in demand, the slow pace of SAF scale-up, the immense technological challenges for long-haul flight, the lack of stringent global policy, and the vast hidden Scope 3 emissions create a colossal mountain to climb.

Reaching net-zero would require an immediate and drastic acceleration in SAF production and deployment, reaching 50-70 pc of fuel use by 2040. It would also need a fundamental shift in consumer behaviour towards reduced flying, especially among frequent flyers and revolutionary technological breakthroughs in hydrogen or battery tech for large aircraft, commercialized at scale within 15-20 years.

All these would need unprecedented global political cooperation imposing tough regulations and ending subsidies and an honest accounting and mitigation of the entire aviation footprint, including Scope 3 and defence.

Beyond the Air Show Gloss

The Paris Air Show 2025 showcased the industry’s ambition. But ambition without commensurate action and accountability is merely spectacle. The decade since the Paris Agreement has been one of soaring rhetoric and soaring emissions, a true climate crash course. The aviation industry stands at a precipice. It can continue its current path, relying on distant technologies and questionable offsets while emissions balloon, making its 2050 NetZero pledge a cruel joke. Or, it can embrace a radical transformation, backed by genuine investment, tough policy, and a shared acknowledgment that the era of unfettered growth on fossil fuels is over.

A world interconnected by flights is precious and mandatory but preserving that connection without cooking the planet demands more than shiny prototypes at an air show. It demands a revolution, starting now. The next decade cannot be another climate crash. It must be the decade of aviation’s genuine, urgent, and accountable ascent towards sustainability. The future of flight and indeed the future of our planet depends on it.

(Rajendra Shende is a former Director UNEP, Founder Director Green TERRE Foundation, coordinating lead author, IPCC that won Nobel peace prize, Prime Mover SCCN, IIT Alumnus. The views expressed here do not necessarily reflect those of Media India Group.)