December 5, 2022

Wood products reduce less than one percent of global carbon emissions – ScienceDaily


The world’s wood products – all paper, wood, furniture and more – only offset 1% of annual global carbon emissions by trapping carbon in woody form, according to a new study.

Analysis in 180 countries found that global wood products offset 335 million tonnes of carbon dioxide in 2015, of which 71 million tonnes were unrecorded by current United Nations standards. Carbon sequestration from wood products could increase by more than 100 million tonnes by 2030, depending on the level of global economic growth.

The findings provide countries with a cohesive first look at how their timber industries could offset their carbon emissions as nations seek ways to keep climate change manageable by drastically reducing emissions.

Yet the new research also highlights how wood products are only a small fraction of the offsets needed for all but a few wood-dense countries.

Craig Johnston, professor of forest economics at the University of Wisconsin-Madison, and Volker Radeloff, professor of forest and wildlife ecology at UW-Madison, published their findings on July 1 in the Proceedings of the National Academy of Sciences.

“Countries are looking for negative net emissions strategies. So it’s not just about reducing our emissions, but pursuing strategies that might have storage potential, and harvested wood products are one of those options, ”says Johnston. “It’s good because you can pursue options that don’t hinder growth. The question is, can we continue to consume wood products and have climate change benefits associated with this consumption? “

To answer this question, Johnston worked with Radeloff to develop a cohesive international analysis of the carbon storage potential of these products, which countries must now consider as part of the Global Paris Agreement to reduce carbon emissions. .

They used data on timber harvest and production of timber products from 1961 to 2015, the most recent year available, from the Food and Agriculture Organization of the United Nations. Researchers modeled future carbon sequestration in wood products using five broad models of possible economic and population growth, the two factors that most affect demand for these products.

Although the production of wood products in 2015 offset less than 1 percent of global carbon emissions, the proportion was much higher for a handful of countries with large wood industries. Sweden’s wood products pool, for example, offset 9 percent of the country’s carbon emissions in 2015, which accounted for 72 percent of emissions from industrial sources that year.

But for most countries, including the United States, wood products mitigated a much smaller fraction of overall emissions in 2015, and that proportion is not expected to increase significantly by 2065, the researchers found. .

Current UN guidelines only allow countries to count carbon stored in wood products created from national wood crops, not wood grown locally and shipped internationally, nor products made from it. of imported lumber. These regulations create a gap between the actual amount of carbon stored in wood products around the world and what is officially counted.

In 2015, this gap amounted to 71 million tonnes of carbon dioxide, equivalent to the emissions of 15 million cars. If these guidelines remain unchanged, by 2065 an additional 50 million tonnes of carbon dioxide could be lost due to this discrepancy. But this additional uncounted carbon does not significantly increase the proportion of global emissions offset by wood products.

Johnston and Radeloff also found that the level of carbon stored in wood products is extremely sensitive to economic conditions. Slow or negative growth could significantly reduce the amount of carbon offset by these industries.

“As the wood products are produced, you add to this carbon pool in the country, but those products end up breaking down. There are carbon emissions today from furniture or lumber that were produced 50 or 75 years ago, “says Johnston.” So if we don’t produce at a rate that at least compensates those emissions, then we’ll actually see that carbon pool become a net source of emissions. “

For example, the Great Recession of 2008 and 2009 turned US wood products from a net carbon sink into a net emitter. A similar effect released millions of tonnes of carbon dioxide from wood products for years after the collapse of the Soviet Union, Johnston and Radeloff found.

The study’s five projections for future economic growth predict that more carbon will be captured in wood products, but unforeseen economic shocks could temporarily reverse this trend for particular countries.

The current study offers a chance to assess current obligations and help countries predict future emissions. The findings could also inform the next round of emissions targets and negotiations, the researchers said.

“We make this data public. The full model for all countries, for all wood products, for all scenarios is available, ”says Johnston. “Now we know what it looks like for each country under a common model and common assumptions moving forward.”