One year into the AHDB baselining pilot – What have we learned?

AHDB Environment Director Chris Gooderham looks back at the first year of our pioneering Environment Baselining Pilot.

A year ago, I said that agriculture was facing the biggest challenge of a generation in demonstrating the positive impact farming systems can have on the environment – something that is amplified by a lack of accurate, on-farm-level data. This is why AHDB, with support from Quality Meat Scotland (QMS), was launching the Environment Baselining Pilot.

On the anniversary of that message, I thought it was timely to look back over the last year to see how we’re getting on and to look forward to the months ahead.

The pilot baseline measurements are only the start of the journey – giving us a point from which to track changes in greenhouse gas (GHG) emissions and carbon stocks over time. That journey will see us collate more data and evidence, particularly to support conversations about the importance of soil carbon and carbon removals/sequestration.

The removals part of net zero

A significant amount of the budget is going into measuring carbon stocks – both above ground in the trees and hedges and below ground in the roots and the soil.

That’s for a few reasons. Firstly, we need to know how much carbon is already stored on the farm. We are looking to see what farming practices are aligned to high carbon stocks and what the overall size of the prize might be if we were able to increase the uptake of such practices.

By measuring this, and then re-measuring in five years’ time, we can see the result of any changes made on the farm. Allowing improvements to be measured, reported and recognised.

The first stage of the on-farm work started at the end of 2024, using aerial light detection and ranging (LiDAR) scanning to measure the above-ground carbon stocks in trees and hedges, as well as mapping water and nutrient run-off risks. It was important that we did that scan during the winter period, while the leaves were off the trees.

This is because the algorithms that convert the scans into numbers have been built based on no leaves. It also means we have a better measurement of the woody biomass and where the ground level is under the trees. It also allows us to provide better run-off risk maps to reflect what happens during periods of excess rain – because we can see how the water would travel under those trees.

Getting all the farms LiDAR scanned while the leaves were off the trees proved a challenge, but we always knew it was going to be.  The main issue was having the right weather conditions to allow planes and drones to fly during that winter period.

Of course, this was not helped by the fact our baselining farms are dotted around the British Isles, so they are not all neatly in a line near an airport. That said, we still managed to scan all but two of the farms, and those two will be done later in 2025.

Carbon audits

In order to get an overview of the farm, and to get more information on the emissions side, all baselining farms are having an Agrecalc carbon audit. Like all carbon calculators, we know there are limitations with the tool.

We know results can change based on assumptions, and we know that carbon audits are using international averages (tier 1) for sequestration and national averages (tier 2) for emission factors. We would like to see them use actual farm data or local averages (tier 3), but that data is not available at the moment.

The carbon audit will provide us with results based on two global warming potential (GWP) measures: GWP100 and GWP*. This will show us the variation between the two reporting methodologies when it comes to methane.

Learnings to date

Things have moved on considerably in the last year, but we should not forget that it’s a pilot and, as such, one of the key elements is to highlight challenges. These could be either gaps in our knowledge or the data, or inaccurate or crude reporting that does not reflect the good work already underway on farms.

Getting the farm report right from the LiDAR scanning has taken longer than we’d hoped, but we wanted to make sure it was right and was easy for farmers to interpret. Those reports are expected to be available by the end of October for all scanned farms.

The soil carbon testing has highlighted a few challenges as well. The biggest one is timing access to the fields – trying to avoid periods where fertiliser or manures have been applied, where crops have been drilled or during harvesting, all of which limit accessibility.

AgriCarbon is working with the farmers to work around those challenges and, at the time of writing, 54% of the farms have been soil sampled.

What happens next?

For most farms, the first thing they will see is their carbon audit results, but those are only part of the picture. For me, what I find fascinating are the visuals that come out of the LiDAR scans and soil carbon testing. They really bring the process to life.

We want to understand what a national baseline might deliver for us, where we accurately measure the environmental outcomes on a farm rather than relying on averages.

That would ensure the good work farmers are delivering is more accurately quantified and reported on, so further improvements can be recognised and hopefully incentivised. The pilot is helping us determine how a national baseline could be made more affordable.

A number of other organisations have been talking to us about the pilot, and we have started to share the protocols we are following with them. That’s something we will make public in the future.

We are also planning to talk about the first set of results in later in the autumn. I’m really excited to see what we’ve found and to use that evidence to support the industry.

As I said a year ago, this project is more than just a pilot, it is a movement to redefine how farmers are recognised for delivering both food and environmental goods simultaneously.

It will demonstrate the true environmental impact of agriculture in Great Britain, the scale and potential of natural carbon stocks and sequestration and the industry’s progress towards net zero. It is facilitating a transition to more informed action and debate about British agriculture.