🌳 When Carbon Credits Grow on Shrubs (Part 1)

Good Friday evening, and welcome to your climate data briefing.

Not long ago, I was digging through New Zealand’s Greenhouse Gas Inventory when I noticed our neighbour’s definition of 'forest' is very different from ours.

In Australia, you could get lost in a forest and still see over the trees.

Our threshold for what counts as forest is low — and that raises questions about how we count carbon and who benefits.

Let's take a look.

When Is a Forest a Forest?

Here’s a patch of western NSW earning carbon credits for regenerating as forest.

In Australia, a 'forest' is defined as:

🪾 Tree height: ≥2 metres
🌳 Crown canopy cover: ≥20% (i.e. how much of the ground would be hidden if you looked straight down from above)
📏 Area size: ≥0.2 hectares
📐 Minimum width: None specified

In New Zealand, a 'forest' is:

🪾 Tree height: ≥5 metres
🌳 Crown canopy cover: ≥30%
📏 Area size: ≥1 hectare
📐 Minimum width: ≥30 metres

Australia’s lower thresholds mean more land qualifies as forest. There’s no minimum width, and canopy cover and height requirements are lower, so small and sparse patches can be counted.

Both definitions comply with the UN's Intergovernmental Panel on Climate Change guidelines, which let countries set their own definitions.

Here’s how ten nations compare:

Why are different definitions allowed?

Countries write their own rules based on national circumstances. Australia’s definition aligns with domestic datasets and covers a broad mix of relevant forest types, from dense rainforest to sparse woodland.

Forest definitions are not meant for cross-border comparison. They exist to track change and estimate carbon storage against a domestic baseline.

Since 1990, Australia reports it has converted 12.7 million hectares into forest — more than half the size of Victoria.

How much carbon that land absorbs depends on what’s growing there. There is no universal figure for the amount of carbon a hectare of forest captures. Sequestration rates vary by forest type and density.

For instance, Tasmania’s forests store nearly twice as much per hectare as those in New South Wales.

What are the issues?

Australia’s latest greenhouse gas inventory credits forests with sinking 66 million tonnes of CO₂-equivalent each year — well above the 43 million tonnes emitted by our largest oil and gas facilities.

But the idea that trees can offset emissions is under fire. Bill Gates calls the notion that tree planting could solve the climate crisis 'complete nonsense.' Earlier this year, EnergyAustralia admitted 'offsets do not prevent or undo the harms caused by burning fossil fuels.'

Even if scrubland does deliver real offsets, Australia’s low thresholds raise a question: how is land with such marginal canopy monitored and rewarded?

We’ll look at that next week.

By the way, The Age / SMH did an interesting investigation on this issue: Is outback scrub really saving the planet?

Blurbs

Worth Your Time

How New Zealand Is Quiet Quitting

New Zealand ran on 88% renewables in 2023. Now, its government is putting ‘climate policy through a shredder.’ It is ditching a ban on offshore oil and gas exploration. Climate initiatives have been quietly axed, including an emergency fund for extreme weather events. Like Australia, the new plan for net zero leans heavily on the Land Use sector (known as Land Use, Land-Use Change, and Forestry or LULUCF), with the country's forestry industry incentivised to plant swaths of non-native pine for carbon credits. (Drilled)

How to Sue for Climate Change

A new computer model links local warming impacts to individual emitters and puts a price on the damage. It creates a world where those emissions were never released and traces the subsequent effects: less warming, weaker local heatwaves, and avoided economic losses like crop failures. Chevron’s conservative toll since 1991 is US$719 billion — two-and-a-half times its market cap. Around 230 lawsuits have targeted fossil fuel companies since 2015, but the high bar for proving liability remains a major hurdle. (The Conversation)

Spain’s Solar Power Meltdown Story

Spain puts just 30 cents into its grid for every $1 in renewables. The European average is 70c. So when a solar fault near the Portuguese border in April caused a voltage surge ‘so big it registered in France and Germany’, everything went dark. Spain increasingly relies on renewables ‘dispersed across rural areas’, generating intermittently with time and weather. With grid maintenance costs passed to consumers, authorities have been loath to overinvest and hike bills. Behind on battery rollout, Spain’s rapid solar uptake risks becoming a 'victim of its own success' and a cautionary tale for other PV players. (Financial Times)

Headlines

What Happened This Week

Australia

Investment in large-scale renewables projects slowed to a trickle  (AFR, 14 August)

Climate Analytics found WA’s gross emissions are up nearly 50% on 2005 levels (Renew Economy, 12 August)

A photographer took stark images of WA’s bleached Ningaloo Reef (ABC, 12 August)

Data tracked federal approvals for 76 renewables projects from 2023 and 2024 and found not one has progressed (AFR, 8 August)

Popular EVs underperformed lab test ranges by 5-23% in ‘real-world’ conditions (The Guardian, 6 August)

World

Climate-fuelled dengue cases rose in the Pacific, with 18 killed, including six children (RNZ, 14 August)

Researchers found an 'extinction of experience' in human connection to nature (The Guardian, 9 August)

Wall Street’s top banks cut fossil fuel financing by 25%, despite the climate commitment exodus (Bloomberg, 7 August)

Final Thought

'The public has much at stake. They are not toddlers to be managed.'
- Zeynep Tufekci

That's your climate data briefing for this week. It's Friday night ... pens down!

💛 Juliette and the OnlyFacts team