[knappe]

It makes perfect sense.

Forest are only carbon sinks if they stay as a forest. The second you cut one down it goes from being a sink to source. Searchinger's argument states that more forests will be grown to be cut down if burning wood pellets (that are shipped from North America to the EU) is considered renewable and that means you're now cutting down even more forests to clear land for growing more trees. The land used is not free; it could have instead stayed a forest and remained a carbon sink. When you compare wood pellets using for generating energy and compare it to other forms of energy generation it no longer holds up as a renewable resource after you take into account the land that could have been kept instead as a forest and carbon sink.

[lazide]

Forests are not long term carbon sinks. They flatline rather quickly.

This is obvious to anyone who has spent much time in a forest, because if this wasn’t the case, forests would be sitting on thousands of feet of sequestered carbon. Instead of a few feet (typically) of non-mineral soil.

Forests also (typically) go through cycles of burning.

The highest rate of carbon sequestration is when a forest is in the 3-25 year old range, because that is when the bulk of the actual growth is occurring.

Renewable doesn’t mean ‘indefinite carbon sink’. Renewable means ‘renews’.

This entire discussion is incredibly ridiculous.

[knappe]

Look dude, read the papers or read the book. I don't have much more to offer you. This isn't just about the forest itself but about the land used to grow the forest.

"In the Carbon Costs of Global Wood Harvests, published in Nature in 2023, WRI researchers using a biophysical model estimated that annual wood harvests over the next few decades will emit 3.5-4.2 billion tons of carbon dioxide (CO2) per year. That is more than 3 times the world’s current annual average aviation emissions. These wood-harvest emissions occur because the great majority of carbon stored in trees is released to the atmosphere after harvest when roots and slash decompose; as most wood is burned directly for heat or electricity or for energy at sawmills or paper mills; and when discarded paper products, furniture and other wood products decompose or burn. Another recent paper in Nature found that the word’s remaining forests have lost even more carbon, primarily due to harvesting wood, than was lost historically by converting forests to agriculture (other studies have found similar results1). Based on these analyses, a natural climate solution would involve harvesting less wood and letting more forests regrow. This would store more carbon as well as enhance forest biodiversity."[0]

[0]https://www.wri.org/technical-perspectives/wood-harvest-emis...

And the original paper that introduced the idea of land use https://www.science.org/doi/abs/10.1126/science.1151861

[vintermann]

Sinks is about flows. The question is about reservoirs. Forests are a long term carbon reservoir. Yes, it's possible to regrow it and let it stay that way. But we don't do that if we regularly chop it down for wood pellets. If we regularly do that, then the carbon in it will spend more of its time in the atmosphere and cause trouble, even if it wasn't pumped from a fossil reservoir.

This is why you can't ignore land use changes in carbon budgets. It's a sound argument, it's not ridiculous at all.

[fodkodrasz]

The soil they create, if they stay alive and are able to retain the soil layer, is gradually washed away (and locally replenished) and is fertilizing the lowlands.

[littlexsparkee]

Even fast growing trees need 10-20 years to start storing significant amounts of carbon and old-growth forests can sequester it for hundreds of years.