The Big Questions

Aviation is one of the hardest sectors to decarbonise - and with demand for flights only growing, the pressure is on to find cleaner fuels.

Sustainable Aviation Fuel (SAF) is being pitched as the industry’s game-changer, promising to cut emissions while keeping planes in the sky.

But: is it really the answer?

In this episode, we unpack what SAF actually is, how it works, and whether it can scale fast enough to matter. From supply bottlenecks to sky-high costs, we look at the hurdles ahead—and ask if it’s a genuine pathway to guilt-free flying or just a drop in the ocean.

Join David Carlin and Simon Messenger as they explore whether Sustainable Aviation Fuel is the future of flight—or just a story that’s taking off without enough fuel behind it.

Artificial intelligence is changing the world at breakneck speed. But with that power comes a big climate question: is AI an energy-hungry problem, or could it be a crucial part of the solution?

In this episode, we explore both sides. From the hidden costs of each AI query - the energy, the water, the booming data centres - to the risks of over-reliance that dull human judgment.

But we also dive into the promise: breakthroughs in science, smarter energy systems, and tools that could accelerate the transition to a low-carbon economy.

Join David Carlin and Simon Messenger as they unpack whether AI is driving us closer to climate disaster - or helping us find the solutions we’ve been waiting for.

The Atlantic Meridional Overturning Circulation (AMOC) is an incredibly critical ocean current system. It moves heat around the planet and shapes global weather. But scientists warn it could weaken—or even shut down—within decades. The result? Severe disruption to Europe’s climate, shifting monsoons, and global ripple effects.

In this episode, we break down what an AMOC shutdown could mean for people and economies worldwide. From freezing winters in Europe to disrupted rainfall in the tropics, the stakes are high—and the timelines may be shorter than many expect.

Join David Carlin (only this week!) as we explore what’s at risk, why it matters for policymakers today, and how we might act now to prevent a shock that could reshape the world.

Carbon taxes are one of the most talked-about tools in tackling climate change. By putting a price on emissions, they aim to fix a market failure: the true costs of climate damage aren’t built into the price of fossil fuels. But how far can this tool really take us?

This episode gives a Carbon Tax 101—what it is, why economists like its simplicity, and how it can cut emissions. We also look at the challenges, from fairness concerns to whether pricing alone can drive the big shifts we need.

Join David Carlin and Simon Messenger as they explore the promise and pitfalls of carbon taxes, and ask: is this the solution, or just one piece of a bigger puzzle?

What does the push to Net Zero really mean for your wallet, for government policy, and for the future of energy?

This week, we break down the forces driving energy prices—from fossil fuel dependence to the real costs of renewables—and explore how decarbonization could deliver cheaper, more secure, and more reliable power.

Whether it’s families deciding if they can afford to heat their homes, or industries struggling to stay competitive, energy prices shape everyday choices and national priorities alike. So how can policymakers balance volatility with the promise of a cleaner future?

Come join David Carlin (only!) on this week’s episode of The Big Questions.

International shipping is the engine of the global economy, moving over 80% of our goods.

However, this essential industry operates as a climate blind spot. Its emissions are so vast they would rank as the world's fifth-largest country (!), but they were intentionally excluded from the Paris Agreement. What's the impact of this?

Last week too, the IMO finally reached a major new climate agreement, but the policy is already facing significant political challenges (notably from the US).

Join Simon Messenger and David Carlin as they discuss the emissions, the political turmoil, and the high-stakes future of the shipping industry in this episode.

In this episode, we dive into how climate change is transforming the U.S. housing market (and wider economy) —and what it means when properties become uninsurable and markets destabilize.

Join hosts David Carlin and Simon Messenger for a powerful conversation with Ivan Frishberg, Chief Sustainability Officer at Amalgamated Bank and one of the leading voices on climate and finance. While the focus of our conversation is on the U.S., the implications will be global. Ivan shares sharp, forward-thinking insights on what needs to change, where finance is falling short, and how popular movements might hold the key to building resilience.

If you care about climate, housing, or the future of the economy, this is one you won’t want to miss.

As birth rates fall and populations shrink, could this be the unexpected solution to climate change?

Fewer people might mean fewer emissions—but the reality is more complicated. The environmental impact may be smaller than you'd think.

So why doesn’t the math add up?

Meanwhile, ageing populations are set to reshape societies. Countries like Japan and South Korea are already feeling the pressure.

Will the value of migrants skyrocket?

Will AI and robots fill the workforce gap?

Join Simon Messenger and David Carlin as they unpack what a shrinking population really means for our planet, our economies, and our future.

This week, Simon Messenger (solo—no David Carlin!) dives deep into the science of climate tipping points. What are they, where do they come from, and why do they matter?

From collapsing ice sheets to shifting ocean currents, learn how Earth’s systems can absorb pressure for a while—until they suddenly snap, shifting into a new and often irreversible state. Think leaning too far back in your chair or bending a stick until it breaks.

So why aren’t we paying closer attention to these critical thresholds? And what can we actually do to avoid the worst outcomes?

Join Simon for a fascinating and urgent look at the hidden triggers in our climate system—and what they mean for our future.

Join David Carlin and Simon Messenger for today's interview with Oliver Dauert, the founder of Wildya.

Forget those "LinkedIn experts"—Oliver is the real deal. He's a genuine authority on biodiversity and nature, boasting deep ecological knowledge gained from years of working in the field.

He dedicates his time to helping businesses grasp the critical importance of nature, not just as a general concept, but as a tangible asset with real value for their operations.

In this episode, Oliver will share his insights and experiences from his work with the private sector through Wildya. He'll explain how businesses can better understand and integrate nature's value into their strategies, demonstrating that ecological health and commercial success aren't mutually exclusive.