Using Crushed Rock to Tackle Climate Change

A previous article focused on the need for large scale carbon sequestration with a look at a project in northern British Columbia that shows promise for meeting this challenge. Its approach takes biodiverse seed packets enveloped in biochar for nutrients and moisture retention and uses drones to spread these casings over wide areas to regenerate forests. This method of reseeding forests works especially well in remote, inaccessible terrain where replanting by hand is impossible.

Forests, or more specifically, the growing of trees, have been scientifically proven to pull carbon dioxide from the atmosphere. The calculations of some scientists, however, suggest that this natural process cannot achieve the scale of carbon drawdown required to offset our ever-growing carbon emissions. They cite the availability of land for forest restoration being the limiting factor. Consequently, another natural process is being considered to enhance and accelerate the storing of carbon not only in forests but on farms as well.  This process occurs when rain dissolves the carbon dioxide that is present in air creating a weak carbonic acid. If this acid falls on basalt rock, it reacts to form a carbonic mineral (calcium carbonate) that locks up the dissolved carbon for hundreds of thousands of years.

Basalt is the most common rock found on Earth’s surface. It is formed primarily from volcanic eruptions. Various forms of basalt are widely used in construction as aggregate in asphalt and concrete mixes and as base layers for highways and railroads. Although dense, this igneous rock crushes easily. Once pulverized into dust it can be spread relatively inexpensively on forest and farmland, making it readily available for rain to wash carbon out of the air and accelerate the process of sequestration. The understanding of this process, called “enhanced weathering” is not new, but because it speeds up a natural process it has only recently been explored for its potential to offset human-made emissions that are causing climate change.

The Future Forest Company, a recent start-up company, is conducting a trial of this speeded up weathering approach on a large birch and oak forest on the Isle of Mull in Scotland. Results of the trial will be known soon. If the data show the expected increase in carbon sequestering, then this accelerated weathering process could potentially capture gigatons of carbon dioxide when applied to forests and on farms around the world. Reseeding of forests is still needed, but enhanced weathering can supplement forest restoration and be applied to farmland as well.

Nature Knows Best - Carbon Farming

For the past 20 years, since Ed Mazria calculated that buildings use almost 50% of energy consumed in this country, I have been on a quest to make buildings super energy efficient, while producing any additional energy needed from site-generated renewables. But now I am coming to believe that there is another option for reducing greenhouse gases that is equally, if not more, important.

A carbon experiment on a small number of ranches in Northern California is establishing a simple, benign way to remove carbon dioxide from the air. UC Berkeley scientists have measured the impact of a one-time spreading of compost ( ½ “ layer) on rangeland and found, to their surprise, that it boosted the soil’s carbon sequestration capacity on average one ton per hectare per year for each of the 8 years they have been testing. They forecast that this sequestration process will continue for at least two decades.

Grazing is the largest land use on the planet and most grazing lands are degraded. If this one-time thin application of compost were applied to a quarter of California’s rangeland, the soil would absorb ¾ of California’s greenhouse gas emissions for the year, and since the effect is cumulative, it would keep doing so for a number of years.

For centuries humans have been bleeding soil-stored carbon into the atmosphere through plowing, overgrazing and poor agricultural practices. These recent compost applications can reverse this and create what scientists call a positive feedback loop. Plants pull carbon dioxide from the air through photosynthesis and transfer a portion of the carbon to the soil through their roots and soil microorganisms, then turn that carbon into a form commonly known as humus. This process improves soil fertility, boosts plant growth and captures even more carbon, while enhancing the soil’s ability to absorb and retain water.

Where is all this compost going to come from and who is going to pay to have ranchers spread it on their land? The compost has to come primarily from cities. San Francisco composts 700 tons of residential and commercial organic waste everyday—the largest such operation in the world. This can become a great resource for ranches. As for compensation, key efforts are being made to incorporate soil carbon offsets in California’s cap-and-trade system as a way to make it profitable for ranchers to restore their land.

Although only recently recognized as a carbon sequestration strategy, “carbon farming” has already captured the attention of the White House and officials as far away as Brazil and China. This inexpensive, low-tech harnessing of natural systems holds the potential to turn the vast rangelands of California and the world into a weapon to reverse climate change.

More Seaweed to Tackle Climate Change and Feed the World

We often think that human activity, however well intentioned, negatively impacts nature. This need not be the case, nor has it always been the case in the past. For example, the tallgrass prairies of our Great Plains and their enormous productivity can be attributed to the fire ecology practiced by Native Americans.

Development of large-scale seaweed farming in our oceans can be another type of human activity to enhance nature’s bounty. An increasing body of research is documenting the potential of growing kelp and phytoplankton forests to provide food, feed, fertilizer, fiber and biofuels to most of the world, while efficiently storing carbon, offsetting or even reversing acidification and increasing oxygen. Kelp grows many times faster than trees, and even fast-growing bamboo.

Human industrial practices and consumption patterns have led to hotter waters and expanding “deserts” in our oceans. Think of dying coral reefs, extensive dead zones in the Gulf of Mexico and elsewhere and sea floors carpeted with plastic microfibers but devoid of life. Scientists have found that 99 percent of tropical and subtropical oceans are almost totally lacking in marine life. With warming, the oceans’ currents and winds are being turned off one by one. These and other changes to our oceans are laid out alarmingly in the recent report by the Intergovernmental Panel on Climate Change.

Proponents of marine permaculture propose building light-weight lattice structures to which seaweed can attach. Near coastlines, they could be tethered to the ocean floor, or be submerged about 80 feet and allowed to drift in the open sea. With kelp and phytoplankton forests come a great diversity of fish as well as crustacean, sea mammals and birds. Fish populations will soar. These kelp farms will also be fish farms without boundaries or outside inputs. The fish will be diverse, wild, untainted and full of omega-3 fatty acids.

Most of the carbon emitted by human activity is contained within the top 500 feet of the ocean. Any farmed seaweed not consumed by ocean creatures or harvested for biogas or fertilizer would die off and sink to the deep ocean floor, sequestering carbon for centuries. Oceans naturally do a good job of moving carbon from surface water to the depths.

Besides mitigating climate change and restoring the health of our oceans, large-scale kelp farms offer the prospect of big returns on investments: increased seafood catches, fertilizers, medicines, biofuels, beauty products and as an additive to livestock feed. In animal feed, it can reduce potent methane emissions from cows and other grazing livestock by as much as 70 percent, while transitioning land for uses other than growing soy, corn and grass for ruminants.

Europe Is Serious About Dealing with Plastic Waste

Placing Responsibility on Producers for Their Plastic Waste Is Yielding Results

 In the natural world, every bit of waste is a food or input for another creature or process. Contrast that with plastics in our society. Almost all our plastics litter, pollute, and harm creatures and habitats.

 Starting a few years ago, the European Union (EU) launched major efforts to handle the 28 million tons of plastic waste it generates annually. Its approach is to create a circular plastics regime. The EU is already driving investments and innovations toward circular solutions in many sectors of its economy, lessening their carbon footprint and, according to experts, making them increasingly competitive worldwide. A circular economy is one in which products and materials are kept in use along their entire life, from design and manufacture to reuse or recycling — much like with natural systems. Europe’s closed-loop plastics system means every product will be designed and made so that it and its components will be used for as long as possible, repaired or refurbished if broken, and recycled into secondary raw materials multiple times without losing quality.

 Plastics is big business, employing 1.5 million people in Europe and generating $410 billion in 2019. By pushing money and innovation into the design, use, and recyclability of plastic products, the EU was able to set industry-wide targets: All plastic packaging in the EU market must be recyclable by 2030. Starting this year, companies will no longer be allowed to dump plastic waste on poorer countries. The EU has just this year banned the sale of 10 plastic products — those that most commonly litter its beaches and shores, including cutlery, straws, plates and Styrofoam food and beverage containers. By 2030, there will be a total ban on throwaway plastics, a comprehensive reuse system for all other plastics, and a large and potentially lucrative continental market for recycled plastics.

 Perhaps the most powerful aspect of the EU’s plastics strategy is creating producer responsibility. Any company introducing packaging or packaged goods will be responsible for the full cost of the collection, transportation, and recycling of its products. In essence, the polluter pays. Extended producer responsibility is already widespread in Northern and Central Europe. For example, German companies are paying $1.75 billion in fees annually to finance the transport, sorting, and recycling of their plastic waste end-materials. Since January this year, plastic producers in Europe now pay $940 per ton for non-recycled plastic waste. Producer responsibility is leading to the redesign of products with circularity in mind. Already, plastic recycling has soared to three times what it is in the U.S.

 The EU’s strategy for plastics will help it reach its ambitious climate target: cutting greenhouse gas emissions (GHG) 55 percent below 1990 levels by 2030. Reducing oil-based plastics production is projected to shave 3.4 million tons of CO2 from their carbon footprint. Imagine the impact on climate change if producer responsibility were applied to GHG emissions.