Why Net Zero Alone Cannot Stop Global Warming

Thank you for having me. I want to start with a question that sounds settled but is not: if we reach Net Zero, does global warming stop?

To answer that we have to look at the Earth's energy balance — the difference between the sunlight we absorb and the infrared radiation we emit back to space.

Roughly speaking, the planet is absorbing about one watt per square metre more than it radiates. That surplus goes overwhelmingly into the ocean.

Now, here is the part that is rarely discussed publicly: some of the sunlight we would otherwise absorb is being scattered away by pollution. This is global dimming.

Sulphate aerosols from combustion are short-lived. Take away the pollution and, within weeks, that reflective layer disappears.

So Net Zero, which is essential, also removes a coolant. The warming that was masked becomes visible. This is not an argument against Net Zero — it is an argument for doing something else as well.

That something else is adaptive mitigation: increasing the reflectivity of the surface where people actually live and grow food.

We make these reflectors out of waste — discarded plastic, aluminium, glass and bamboo — because the material has to be available everywhere and cost almost nothing.

In the field we measure large reductions in surface temperature under and around the structures, with direct benefits for crops, livestock and people working outdoors.

The conclusion is simple. Cut emissions, and at the same time reflect sunlight. One buys the future; the other protects the present.