That will lead to better quality land use change.
Upton was responding to farmers’ concern the Government’s Zero Carbon Bill will lead to wholesale afforestation with inevitable land use change in response to climate change.
But the shape of that land use change can be better managed by farmers working together and taking a landscape approach to establishing forests rather than blanket planting by those seeking to simply offset their emissions, Upton said.
“That’s the bit I think needs to be thought about a bit harder.”
But he is not recommending emission targets for the Government to adopt, saying such decisions should be left to the Climate Change Commission.
Farmers feel the Government’s methane target means they are doing most of the heavy lifting for the country to meet international emission obligations.
Whatever targets are chosen the rationale and their expected economic and temperature impacts should be made clear and explicit, something that is lacking in the Bill.
“If there are reasons why the temperature objectives and emissions reduction targets for fossil emissions and biological emissions are different, these should also be clearly stated.”
Farmers and rural communities should seek clarity on the Bill’s implications.
The Bill aims to reduce net emissions of carbon and nitrous oxide to zero by 2050, gross methane by 10% by 2030 and by 24% to 47% by 2050 compared to 2017 levels.
Forests can be used to offset carbon and nitrous oxide emissions but not methane.
Upton quotes modelling that shows methane from NZ agriculture does not cause extra warming beyond 2016 levels, emissions need to reduce by at least 10% and 22% by 2050 with further reductions by 2100.
He says separating methane and nitrous oxide targets could still allow NZ to meet the Paris Agreement’s warming goal.
“However, because these gases are shorter-lived in comparison to carbon dioxide I proposed that any biological emissions target could be offset with forests.”
Upton noted the Intergovernmental Panel on Climate Change indicated a gross reduction in nitrous oxide of 26% is needed by 2050.
Using forests to offset emissions will still result in 1.5 million to 3m hectares of new forestry but Upton says it doesn’t have to be blanket planting and, if managed correctly, can have multiple environmental benefits.
Excluding forests from offsetting fossil fuel emissions recognises the difficulty of guaranteeing their permanence and avoid a delay in tangible steps to reduce total carbon emissions.
Allowing farmers to offset methane and nitrous oxide emissions will result in better management of forest planting and address environmental issues such as water, soil, erosion, biodiversity and climate as a landscape rather than the alternative of wholesale planting of trees based on property boundaries.
“The best chance, it seems to me, of making a revolutionary step and to get better suited land use, contour and physical characteristics is if landowners operate together.”
Upton says forestry will be a cheap source of mitigation and those seeking to offset carbon emissions do not have the same drivers as landowners.
“Do we want our landscape change in NZ driven by forestry and trees in respect to soil, water, erosion, climate change and biodiversity challenges or driven by urban NZ wanting to park its waste?”
