Natural Climate Solutions: Maybe Not What You Think

by Stevan Harrell

Technology can save us from climate change, or so goes the hope and hype in today’s media. Clean, smart grid, electric vehicles, all-electric buildings, green hydrogen, carbon capture and storage — if we just get off fossil fuels, and do it fast, we might save ourselves from the worst, or, at least, hold global warming below two degrees Celsius (one and a half, I fear, is a pipe dream, or, in today’s euphemism, “aspirational”). Most of these fixes are plausible, and might actually be possible if it weren’t for politicians and their oil-and-gas company backers. 

There are reasons, however, to look beyond this techno-optimist narrative. Technologies have their environmental, political, and social costs. Mining the minerals used to build batteries, solar panels, and wind turbines will trash landscapes, some of them sacred to Native peoples or conserved in National Parks or other protected areas. Wind and solar farms have to go somewhere, and they spoil both views and sometimes valuable farmland. Dirty industry (and green industry is also dirty) too often gets put, unjustly, in or near Native, minority, or poor communities. And, even if we can avoid these environmental and social costs, no projection shows us ramping up our green tech fast enough to meet the 1.5-degree goal, or even the more realistic 2-degree limit. 

Natural Climate Solutions
So, it’s understandable that we turn to “natural climate solutions,” looking for ways that will help slow global warming without ruining our landscapes, homes, and sacred lands, and might even restore some of the damage we have unthinkingly done to them over the last two centuries. Forests store carbon in standing biomass and in soils, and well-managed farms also build soil carbon, keeping it in the ground rather than releasing it to the air in greenhouse gases, including carbon dioxide and methane. 

A recent report by scientists from the University of Washington and The Nature Conservancy shows how natural climate solutions can contribute to carbon sequestration and thus to climate action in Washington. Forests can be conserved unlogged, or, more practically, if we want to preserve our wood products industry (we do), logged in longer rotations and then replanted with diverse species. We can plant trees in formerly forested areas, as the Whatcom Million Trees Project is already doing. We can pyrolize logging residues to biochar, which is almost pure carbon, and add it to the soil, rather than burning the slash piles and releasing the CO2 to the air. Kulshan Carbon Trust is working on making biochar economically feasible. 

Regenerative agriculture can also play a big part. Cover crops, no-till farming, rotational grazing, and advanced practices of nutrient (i.e. manure) management all help keep carbon in the soils. Manure digesters can extract methane and use it as a “nonfossil” hydrocarbon fuel to generate energy, while the nitrogen-containing manure provides nature’s best fertilizer — better for the soil and the crops, and, unlike chemical fertilizers, not made from fossil fuels. Preserving agricultural land from development also sequesters some carbon, especially if it’s farmed without those chemical fertilizers. 

Statewide, according to the UW report, these measures might reduce our greenhouse gas emissions by between 5 and 8 percent, depending on how aggressively we pursue them. The report, however, is less enthusiastic about Whatcom County. Most of the carbon sequestration we could gain from better forestry practices would happen in southwestern Washington, where commercial forestry dominates landscapes. Most of the gains from more sustainable farming would occur in Eastern Washington where large commercial farms are most concentrated. If we aggressively implemented natural climate solutions in forestry and agriculture in Whatcom County, it would reduce our local greenhouse gas emissions by 2 to 3 percent. The main way to mitigate our contribution to climate change is still through green energy and aggressive electrification. 

Why Natural Climate Solutions Are Necessary
The 2 or 3 percent of greenhouse gas emissions we could avoid with natural climate solutions are not trivial. Every little bit helps. But there are much more important reasons for pursuing natural climate solutions, and they have to do with climate adaptation, making our homes and our environment more resilient to the higher temperatures, increased winter rains, and summer droughts that all climate models tell us to expect. All of the natural solutions proposed in the report, and others besides, will help us build climate resilience. 

Take forestry for example. Recently the state Department of Natural Resources has announced that about 1,000 acres in the Lake Whatcom Watershed east of the lake will be conserved from logging through a new carbon credit project. These thousand acres are a drop in the statewide bucket of forest carbon sequestration, but conserving them will have a other major effects — preventing soil runoff and erosion, and decreasing the release of sediments into the lake, which provides the majority of drinking water for Bellingham and nearby areas. 

Or, look at lengthening forest harvest rotations. They do have a carbon benefit, because standing biomass stores carbon and cutting it releases some to the air through slash-burning or decay, though some of the carbon is also stored in lumber. But, studies have shown that, for example, harvesting Douglas-fir at 60-80 years instead of the conventional 40 years also makes more of the cut wood available as lumber useful for construction. Not only does less of the tree volume go up in CO2-rich smoke, but we can use wood to replace carbon-intensive materials, such as steel and concrete. 

Multispecies and varied-age plantations may sequester only a little more carbon than the ordinary monocultures, but they have ecological benefits similar to those of preserving forests. Clearcuts promote erosion and runoff, which increases flood severity, as well as reducing species’ habitat. Selective thinning can produce the same environmental benefits as multispecies planting, and we ought to encourage both. 

We have limited commercial forestry in Whatcom County, but we have a lot of farms. And climate-friendly farming can contribute even more than sustainable forestry to climate resilience here. No one needs to be reminded of the devastation that last November’s floods brought to our farms and towns. Soil conservation practices, including cover crops and rotational grazing, can protect land that is flooded from losing its soil nutrients. 

Riparian forests benefit both farming and forestry, and are supremely important for climate resilience. A bare streamside allows sediment to enter streams, diminishing their capacity to hold floodwaters, as well as clogging the gravelly streambeds that salmon need for spawning, hatching, and the first stages of growth. A streamside shaded by trees not only retards runoff, but also keeps water cool enough for migrating salmon and prevents evaporation of scarce summer water. 

We can also contribute to climate resilience by restoring historical landscapes. Where we can afford it, buying back properties in flood-prone areas and setting dikes back from riverbanks to re-create historical wetlands stores inevitable floodwaters in natural wetlands (which also sequester carbon) and restricted floodways rather than allowing it to flood homes, roads, and farms. 

To reduce emissions, we need to eliminate fossil fuels; natural climate solutions can only sequester a little carbon and cut emissions a bit. But, given that the climate is already warming and will warm more in the coming decades, we need to prepare for it. Natural climate solutions offer numerous ways to reduce the impact of the warming that is happening and will continue to happen. To confront climate change, we need to combine natural and technological solutions. Without either, we are in for decades of bad trouble, but all the natural solutions are technically and socially feasible; all we need are the will and the funds to implement them. Let’s get going.  

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Stevan Harrell retired in 2017 after 43 years at the University of Washington, teaching anthropology, environmental studies, and Chinese studies. He and his wife Barbara moved to Bellingham and are now happy ‘Hamsters. Steve writes frequently about climate and environment issues, and is a member of Whatcom County’s Climate Impacts Advisory Committee.

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