Why Global Heat Records Matter for Green Tech

Global temperature records haven't just been nudged higher recently—they’ve been smashed. 2024 became the first year with average global temperatures 1.5°C above pre‑industrial levels, and 2023 and 2025 sit right beside it in the rankings.

For anyone building or buying green technology—from AI-powered energy systems to industrial decarbonisation tools—this isn’t background noise. These records are the scoreboard. They tell you how fast risk is rising, how urgent net-zero really is, and where your investments in climate solutions will be most valuable.

This matters because climate tech teams are planning around a world that warms at a certain pace. The last three years have been hotter than most models expected, so the natural question is: did we underestimate the problem, or is this a temporary spike? The reality is more nuanced—and more actionable—than either panic or denial suggests.

Below, I’ll break down what’s driving the record heat, what might stick, and how smart use of AI and green technology can turn this science into better decisions, better products, and better climate risk management.

What’s Really Driving Recent Record-High Temperatures?

The recent burst of global heat isn’t caused by a single “mystery factor.” It’s the result of human-driven warming plus a stack of natural and policy-related effects that all happened to line up in the same direction.

Four main contributors have been studied in depth:

• A strong but oddly timed El Niño in 2023–24
• Rapid declines in sulphur dioxide (SO₂) pollution, especially from shipping and China
• The unusual Hunga Tonga volcanic eruption in 2022
• A stronger‑than‑expected solar cycle

On top of that, there’s the usual natural climate variability—random swings that push temperatures a bit above or below the long‑term trend.

When scientists put numbers on these factors, the combination explains most of the extra heat in 2024 and about half of the unexpected warmth in 2023. That’s important: we are not watching physics “break.” We’re watching several known drivers stack on top of long‑term warming.

For green technology teams, that means climate projections are still usable—if you understand what’s noise, what’s trend, and where risk may be shifting upward.

How Much Did El Niño Really Matter?

El Niño events temporarily warm the planet by heating the tropical Pacific Ocean and shifting weather patterns. Historically, a strong El Niño adds about 0.1–0.2°C to global temperatures in the year after it peaks.

The 2023–24 El Niño was the fourth-strongest on record (by one common index), but not as intense as 1998 or 2016. Yet global temperatures around it were off the charts:

• 2023 was about 0.18°C warmer than expected from the long‑term trend
• 2024 was about 0.25°C warmer than expected

What made this El Niño strange was timing and persistence:

• Heat arrived early – global temperatures surged about four months before the El Niño peak, unlike any other strong event in the modern record.
• Heat lingered – temperatures stayed high for about 18 months after the peak, even after the Pacific cooled back toward neutral and mild La Niña conditions.

When researchers crunch the numbers, they estimate that El Niño contributed roughly:

• ~0.01°C of extra warming in 2023 (with big uncertainty)
• ~0.13°C in 2024

So El Niño clearly helped, especially in 2024, but it’s not enough on its own to explain why these years were so extreme.

Why this matters for climate and green tech planning

For energy companies, grid operators and climate‑sensitive industries, this has direct operational implications:

• Strong El Niño years are early warning years for extreme heat, wildfires, and demand spikes.
• AI‑driven forecasting systems can treat strong El Niño signals as a risk multiplier when planning cooling loads, renewable output, and grid stability.

If you’re building AI tools for smart cities or climate‑resilient infrastructure, El Niño needs to be hard‑coded as a feature in your risk models, not an afterthought.

Cleaner Air, Hotter Planet: The Sulphur Dioxide Story

One of the most counterintuitive drivers of recent warming is cleaner air.

Sulphur dioxide from burning coal and oil forms reflective aerosols that cool the planet by blocking sunlight. Over past decades, these aerosols have masked about one‑third of historical warming. As we reduce air pollution for health reasons, we’re also removing a temporary cooling shield.

Over roughly the last 18 years, global SO₂ emissions have fallen by about 40%, with two big drivers:

• China: ~70% reduction in SO₂ since 2007
• International shipping: ~80% drop in sulphur content of marine fuel since 2020 due to tighter rules

Most studies find that the new low‑sulphur shipping regulations warmed the planet by around 0.03–0.08°C. A single outlier study suggests as much as 0.2°C, but that’s not where the bulk of evidence sits.

Combining all the best estimates, the overall effect of declining SO₂ from 2020–2024 is roughly:

• ~0.04°C extra warming by 2023
• ~0.05°C by 2024

Crucially, SO₂ decline isn’t new—since 2007, reduced aerosols are estimated to be responsible for about one-quarter of all warming. What’s new is that the shipping rules gave this trend a small additional push.

Implications for net zero and climate models

Here’s the thing about aerosols: if models have underestimated how strongly aerosol cuts warm the planet, they might also be underestimating climate sensitivity overall.

For green tech developers and investors, that would mean:

• Stronger warming for a given CO₂ budget → stricter timelines for decarbonisation
• Higher value on deep decarbonisation solutions (electrification, storage, green hydrogen, carbon removal)
• More pressure for AI‑enabled optimisation in energy systems, buildings and industry to squeeze emissions down faster

Cleaner air is non‑negotiable for public health. The lesson is not “slow down on pollution controls.” The lesson is accelerate CO₂ and methane cuts so we’re not relying on dirty air to hide the heat.

Did the Tonga Volcano or the Sun Cause This Spike?

Two other suspects—Hunga Tonga and the current solar cycle—have grabbed attention, but their roles are modest and well‑constrained.

Hunga Tonga: lots of water, little net warming

The Hunga Tonga–Hunga Ha’apai eruption in early 2022 was huge, sending a plume 55 km into the atmosphere and injecting around 146 million tonnes of water vapour into the stratosphere.

Water vapour is a strong greenhouse gas, but in this case the net effect is surprisingly small because:

• The eruption also added sulphur that formed cooling aerosols.
• The combined impact of extra water vapour plus aerosols appears to be slight net cooling, especially in the Southern Hemisphere.

Using an emulator model (FaIR), researchers estimate Hunga Tonga cooled global surface temperatures by about:

• −0.01°C in 2023
• −0.02°C in 2024

So if anything, the volcano trimmed a tiny bit off what would otherwise have been even hotter years.

Solar cycle 25: a measurable but small boost

Solar output naturally cycles every ~11 years. The current solar cycle 25, which began around 2020, is the strongest since at least the 1980s.

The change in total solar irradiance is tiny in percentage terms—about 0.01%—but it still adds up to up to ~0.1°C of temperature swing over a decade.

For this cycle, best estimates suggest:

• ~0.04°C extra warming in 2023
• ~0.07°C in 2024 (with a one‑ to two‑year lag)

So yes, the sun helped nudge us warmer, but we’re talking hundredths of a degree, not the core of the problem.

If your board, clients, or stakeholders are still blaming “just the sun,” you can safely and clearly say: recent solar changes explain only a small slice of current record heat. The main driver is still greenhouse gases.

Natural Variability vs. Structural Change: Are We Seeing a New Normal?

Once you add El Niño, aerosol cuts, solar changes and the minor volcanic effect together, most of 2024’s excess heat and roughly half of 2023’s can be explained. The rest comes from natural year‑to‑year variability.

Historically, global temperatures have bounced around the underlying warming trend by up to ±0.15°C from one year to the next. A year like 2023—around 0.18°C above the expected trend—should occur roughly once every 25 years in the long record. 2024 looks more like a one‑in‑several‑decades event.

That sounds extreme, but here’s the catch: those probabilities depend on how you define the “expected” warming level. When you use updated estimates that already include the impact of aerosol cuts and other recent forcings, 2023 and 2024 look more like rare but plausible events, not physically impossible ones.

The cloud and albedo wildcard

One of the most important open questions for the next decade is what’s happening to clouds.

A recent study in Science found a marked decline in Earth’s reflectivity (albedo) over the past decade, mainly due to reduced low‑level cloud cover. Less reflective clouds mean more solar energy absorbed and faster surface warming.

The potential explanations are:

• Natural variability (short records make this hard to rule out)
• Stronger‑than‑modelled impact of aerosol reductions on clouds
• A structural response of clouds to global warming itself

If the last two are significant, the implications are big:

• Climate sensitivity could be closer to the higher end of current ranges.
• The kind of heat seen in 2023–24 might “be here to stay” rather than a temporary spike.

For climate and green technology strategies, that argues for no‑regrets moves:

• Design infrastructure assuming higher extremes sooner
• Use AI‑driven scenario tools to stress‑test assets under high‑sensitivity warming paths
• Prioritise solutions that reduce both CO₂ and short‑lived climate pollutants (like methane) quickly

What This Means for Green Technology and AI‑Driven Climate Action

Most companies still underestimate how directly this physics feeds into business strategy.

If warming is accelerating modestly due to aerosol cuts, cloud changes, and natural cycles on top of relentless greenhouse gas increases, then:

• Heat risk is front‑loaded – extreme years like 2023–24 will appear more often in the 2030s than older risk models assumed.
• Resilience and decarbonisation both become revenue‑critical. Climate‑proof assets and low‑carbon products won’t just tick ESG boxes; they’ll determine competitiveness.

Here’s where AI and green technology are already starting to matter:

• Smart grids and demand response use machine learning to anticipate heatwaves and rebalance electricity use, preventing blackouts when AC demand spikes.
• Industrial optimisation systems cut energy use and emissions in real time, responding to temperature, prices, and grid carbon intensity.
• Climate‑aware urban design tools simulate heat islands, flooding and air quality, guiding where to invest in cooling, green spaces, or building retrofits.
• Portfolio and supply‑chain risk engines ingest climate and weather data to flag assets and suppliers most exposed to heat, drought or storm‑driven disruption.

If you’re building in the green tech space, the science of recent record temperatures is not just interesting—it’s a design brief. You’re building tools for a world where:

• 1.5°C is no longer theoretical, it’s observed.
• Aerosol cuts make further near‑term warming likely even if CO₂ emissions plateau.
• Natural variability will throw more “freak” years on top of an already hot baseline.

The opportunity is clear: use AI and advanced analytics to translate this complexity into simple, actionable decisions—for grid operators, city planners, manufacturers, property owners, and finance.

Where We Go From Here

The spike in global temperatures over 2023–2025 isn’t a glitch in the climate system; it’s what you get when long‑term warming meets El Niño, cleaner air, a strong solar cycle, and possible shifts in cloud behaviour.

For the green technology community, the message is blunt: there is no slack left in the system. Cleaner air has removed some of the disguise; we’re now seeing more of the warming we’ve already paid for with past emissions.

That’s exactly why AI‑enabled climate solutions are so critical right now. The businesses that win this decade will be the ones that:

• Treat record heat as baseline, not anomaly
• Embed climate physics in their data models, product roadmaps, and risk frameworks
• Use green technology and AI not only to cut emissions, but to stay operational and profitable in a hotter, more volatile world

The next question isn’t whether records will be broken again. They will. The real question is: will your technology be ready for the climate that’s already arriving?