Millions more trees isn’t the climate fix New Zealand thought

Millions more trees isn’t the climate fix New Zealand thought

The seeds of New Zealand’s recent forestry boom were planted in 2019, when the country’s emissions trading scheme required companies to use only domestic measures to compensate for CO2. In practice, it prohibited companies from buying carbon offsets developed abroad to shrink their carbon footprint.

At the same time, the new rule amplified an existing, and unusual, feature of the policy. Companies doing business in New Zealand are allowed to offset 100% of their emissions with credits generated by domestic forest projects. Most countries limit the use of offsets to push more fundamental cuts to CO2 emissions.

Since 2019, the country has added 175,000 hectares (432,000 acres) of forests, almost all the fast-growing, carbon-sucking Pinus radiata pine. But the new growth has increased waste from forestry—the logs, leaves and branches known as “slash”—more than doubled the damage of the flooding caused by last year’s Cyclone Gabrielle.

While those might be worthwhile trade-offs for significant long-term reductions in climate-warming CO2, the current system doesn’t really achieve that either, experts say.

Forests do absorb a lot of carbon dioxide, but their efficiency wanes over time. To achieve the same environmental effect over decades, “you’re going to have to keep planting more and more forests,” said John Saunders, a senior researcher at Lincoln University’s agribusiness and economics research unit. “That isn’t actually solving the problem.”

One problem with the current forestry credits is that they’re used to offset CO2 emissions, typically from fossil fuels, which linger in the atmosphere in perpetuity—which means the forest also has to live forever, against the odds of disease, fire, storm or human behavior.

“Pine production and permanent forestry are legitimate land uses,” Parliamentary Commissioner for the Environment Simon Upton wrote in a report on land-use change, published May 22nd. “But afforestation should not be incentivized by treating it as a cheap way to offset fossil fuel emissions.”

But biogenic methane, the greenhouse gas emitted by livestock, has a greater warming effect but for a shorter period of time. Starting in 2030, farmers will have to pay for those emissions or find a way to offset them. Forestry, Upton says, could be a solution.

“For short-lived gases like methane, the goal is to reduce emissions to an acceptable flow rather than eliminate them altogether,” he wrote. Using forests to offset methane emissions “is a more justifiable strategy than using it to offset fossil carbon dioxide.”