Climate Change: Nature-based Solutions (STC Report)

Baroness Bennett of Manor Castle Excerpts

Thursday 9th February 2023 Grand Committee

[Baroness Bennett of Manor Castle (GP)]

My Lords, I thank the committee for the opportunity to speak in the gap, the noble Baroness, Lady Brown, for her excellent introduction to this report, and the noble Lord, Lord Patel, for his chairmanship of the Science and Technology Committee.

This valuable, forensic and detailed report identifies that in this area of climate policy, as in most of them, the Government have rhetoric but no plans for delivery—as the title suggests. First, the report, says that

“the UK does not have the requisite skills to deliver … solutions at scale”

and no plans to create them. Secondly,

“there is huge uncertainty about the details of policies that will incentivise nature-based solutions”.

Thirdly,

“more funding is required in several key areas”.

However, I want to focus on one crucial sentence in the report:

“Nature-based solutions are not a get out of jail free card.”


We have both to stop emitting greenhouse gases and to restore our natural world. No trade-off is scientifically possible. Offsetting is a con, a cheat, a fiction. I am building here on the comments, in particular from the noble Baroness, Lady Worthington, but also from the noble Viscount, Lord Stansgate, and the noble Baroness, Lady Sheehan. One way of explaining this is by looking at the difference between biology and geology.

First, as the report says, there is scientific uncertainty about how much carbon is stored, and how it can be stored in different habitats, and how long it will remain. The timescale of ecosystems—of biology—is, if you are lucky, years, but it is often months, days, or even minutes. A wildfire sweeps through a forest—I grew up in Australia, and I have watched bushfires all too close up—and, within a blink of an eye, a lot of the so-called stored carbon is in the atmosphere.

By contrast, geological timescales run to hundreds of millions of years. Up to around 400 million years ago, carbon dioxide levels in the atmosphere were up to 6,000 parts per million. We are now at less than a 10th of that, albeit 50% up from the level at the start of the industrial revolution. Over hundreds of millions of years, geological processes locked vast amounts of carbon underground, mostly deep underground. It was never going to emerge, at least on our human timescale—if you take a 24-hour timescale, we as a species have been on this planet for just one second—until we started to dig it up. The best possible carbon capture and storage is to leave the coal in the hole, the gas in the ground, the oil in the orb. That carbon capture and storage is free, certain and essential.

Secondly, biological systems are living systems. They are flexible, ever changing, adaptive, complex far beyond our current understandings. Unlike claims still sometimes made, just dropping a lot of organic matter into the soil—as good an idea as that is for both biodiversity and food security—will not necessarily increase soil carbon. To quote a recent journal article,

“Persistence of organic matter in the soil depends on chemical, physical, environmental, and/or biological factors.”


It is complex.

The fact is that biology is not going to rescue us, which means that we have to stop growing our economy. We have to operate within the physical limits of this one fragile planet. We have to rescue ourselves by transforming our economic and social system from a way of life built on carbon emissions to one that will stabilise this planet.