For peat’s sake: Turf cutting for home use 162 times over limit
THE amount of carbonemitting peat extraction carried out on our bogs for home use has been vastly under-reported, a study has found.
Research funded by the Environmental Protection Agency (EPA) found almost 65,000 hectares of raised bog across Ireland has been cut up for domestic use.
The amount is nearly 162 times more than the 400 hectares declared in Ireland’s official report on annual greenhouse gas emissions to the United Nations.
Using satellite images from Google Earth Engine, and an AI algorithm, the research methods give a bird’s eye view of Ireland’s bog use.
Turf-cutting releases carbon and other greenhouse gases into the atmosphere.
The study, which its authors claim is the ‘first high-resolution wall-to-wall’ research of its kind in Ireland, focused on the land use of raised bogs, which account for 36% of peatland, while blanket bogs make up the remainder.
‘Given their significant role in climate mitigation, it is essential to quantify the emissions resulting from land use degradation of these ecosystems,’ the research says.
Scientists say peat is the least carbon-efficient fossil fuel, producing more CO2 emissions per energy unit than oil, natural gas or coal.
Previously, cloudy conditions made it difficult to get a clear picture of bog use, but scientist Wahaj Habib said using Google Earth Engine has been a game-changer, as it contains a massive library of satellite imagery to carry out the research.
‘It is quite difficult to map the landscape with satellite imagery in Ireland due to persistent cloud cover. This was one of the obstacles faced by previous studies,’ said the postdoctoral researcher at Trinity College Dublin.
‘The use of AI and Google Earth Engine allowed us to generate a cloud-free composite image using approximately 500 scenes from satellite images.’
The research found agricultural grassland made up 43% of the land use on raised bogs, forestry was 21%, domestic cutover was 11%, and industrial cutaway was 10%, while remnant peatlands accounted for 13% of land use. Water bodies and builtup areas made up 1% each.
The study also revealed that previous reports on bog use have been way off the mark.
In Ireland’s National Inventory Report 2023 – an annual register of emissions required by the UN Framework Convention on Climate Change – the figure for domestic harvesting of all bogs is given as 400 hectares.
The EPA admits in the 2023 report that the extent of domestic harvesting ‘is poorly quantified’. Overall, it says managed wetlands – defined as bogs ‘commercially exploited for public and private extraction of peats and areas used for domestic harvesting of peat’ – are 82,984 hectares for both raised and blanket bogs. But the findings say peat extraction on the raised bogs alone ‘is considerably more prevalent than currently reported’.
‘It extends to approximately 119,000 hectares, which is 70%
‘Degradation of rare habitats’
higher than the managed wetland area figures for all peatlands, both oceanic-raised and blanket bog, reported in Ireland’s National Inventory Report,’ the study said. ‘The results have revealed widespread degradation of these globally rare habitats, making them net emitters of CO2.’
Mr Habib said the findings show emissions are at least twice what has been reported. ‘The numbers don’t align, even for raised bogs, which represent only one-third of the total peatlands,’ he said.