The Overlooked Heroes of Coral Reefs

Sea Cucumbers Maintain Coral Reef Biodiversity and Counter Ocean Acidification

Coral reefs cover only a small area of ocean floor, mostly along tropical coastlines. Their importance ecologically, however, is disproportionate to their prevalence. They protect coastlines from storms and erosion, serve as nurseries for fish, are critical to ocean biodiversity, generate half of the earth’s oxygen, and absorb nearly a third of manmade carbon dioxide emissions. Tragically, half of all reefs have died in the last 30 years. Scientists are saying that warming waters, increasing ocean acidity, pollution, and overfishing threaten the remaining reefs in the next 20 years. 

Coral reef restoration is expensive, according to NOAA (National Oceanic and Atmospheric Administration), costing about $1 million per acre. The main restorative approach is nurturing scraps of coral until they are large enough to replant on reefs. Through genetic research, scientists are hopeful of finding or developing more heat-tolerant species. Perhaps the most effective and least costly option is to encourage nature’s process by promoting healthy populations of sea cucumbers. These scavengers of the sea floor are garbage collectors and nutrient recyclers. It turns out that these slimy, faceless creatures play a critical role in maintaining coral reef health and biochemical balance.

Sea cucumbers’ digestive systems transform their diet of sand and bio detritus into nitrogen-rich, aerated sediment on which coral and algae rely. Not only do these vacuum cleaners of the ocean floor maintain healthy oxygen and nitrogen levels in the sediment, but their excrement also buffers reefs against acidification, a problem linked to ocean warming. Calcium carbonate, the building block of coral skeletons, is becoming increasingly scarce because of increasing acidity. The ammonia in sea cucumber waste increases the availability of calcium carbonate in the reef environment.

Scientists have struggled to assess how significant sea cucumber excrement is. Recently, an Australian research team, using drone surveys, satellite imagery, and direct observation, has gained a more accurate understanding of how beneficial it is. They estimate that there are three million sea cucumbers on the Heron Island Reef, the target zone of their study, and determined that each creature produces almost one and a half ounces of waste each 24 hours. Of course, this can vary widely between specific creatures, as they have been found to be from a few inches to six feet in length. An average of one and a half ounces aggregates to the weight of five Eiffel Towers of excrement each year on their research reef.

Because sea cucumbers are eaten as a dried delicacy in many Asian countries and considered to have medicinal properties in China, their populations are being heavily harvested and are declining at an alarming rate. Over 70 countries currently harvest these creatures. Drone surveillance techniques like those used by the Australian researchers could be employed to monitor sea cucumber numbers. Last year, the first sea cucumber conservation reserve was set up off an Indian island. Hopefully, this is just the first of many.

Hempcrete: A Carbon-Negative Insulation

Hempcrete Moderates Indoor Humidity and Temperature, While Being Fire, Mold, and Insect Resistant

The next frontier in green building is emerging as carbon-sequestering materials. Incorporating such materials into tight, energy-efficient building shells has the potential to fully offset the 40 percent of total greenhouse-gas emissions that structures contribute to global warming. One such material is hempcrete, an innovative insulation that is better for people and the planet.

Hempcrete, or hemp lime, as it is sometimes called, is made from the woody core of the cannabis plant combined with lime and water. Hemp is fast-growing (typically 3-4 months), likes a wide range of soil and climate conditions, and requires no pesticides. An acre of hemp can sequester an impressive 10 tons of carbon dioxide, more than an acre of trees can sequester in an entire year. When turned into hempcrete, the carbon remains locked in the inner woody layer. The lime binder also sucks up carbon. However, cultivating it does require a good amount of water.

The insulating value per inch of hemp is comparable to fiberglass insulation (R-2.5-3), yet it has none of the harmful synthetic ingredients that fiberglass and most other commercial insulations contain. Hempcrete acts like a toxic-free sponge that absorbs moisture from the surrounding air when it is humid and releases it again when it is dry. This ever-adjusting behavior creates a healthier relative indoor humidity and an improved sense of comfort. It has good sound-dampening properties that also contribute to good indoor environmental quality.

The use of hempcrete is growing rapidly in Europe. It has been used in Paris since 2012 and is now being government-funded in subsidized social housing projects. It is also getting traction in the U.S. but was hindered by a later start because of the legal ban on all hemp uses, only recently lifted.

Although made from the woody core of Cannabis sativa, hempcrete is highly fire-, mold-, and insect-resistant, due to the lime envelopment of the plant elements. Not surprisingly, all the other parts of the plant can be turned into other products. The only negative for hempcrete seems to be that it costs more than fiberglass insulation, about double, although that differential will diminish as it gains market share. The product comes in various forms: batts, blown-in, blankets, and rigid boards.

Hempcrete is part of a class of composite building materials that has received negative-carbon-material classification, and among these, it is the top negative-carbon performer. Many other building materials are now being made and analyzed for their carbon-storing properties. The optimum is to create carbon-storing buildings that also operate on renewable energy, making them zero-net-energy and zero-net-carbon structures.

Ending Our Addiction to Natural Gas Will Not Be Easy

Addressing Climate Change Needs Workers, Investors, and Innovators to Be Involved

The Philadelphia Gas Works, founded in 1836, is the oldest gas utility in the country and still one of the most substantial with its 6000 miles of service lines and more than half a million customers. The nation’s largest gas utility is our SoCalGas Co. The reality, however, is that today all gas providers are facing existential threats from the quickening energy transition that aims to convert buildings from gas to electricity.

The gas industry has gained several decades of reprieve by promoting gas as the bridge fuel between coal and renewables. Nevertheless, as the urgency to address climate change has increased and the monitoring of methane leaks from gas pipes (three million miles of gas pipelines nationally) has revealed gas to be almost as dirty as coal, time is running out for gas.

Increasingly, cities’ climate action plans are targeting achieving carbon neutrality by 2050 or sooner. Banning gas from new construction is a relatively easy first step and will be policy in California in a few years. Much thornier is how to get gas out of existing buildings: Almost 60 percent of the country’s 120 million houses use natural gas.

The first step in a comprehensive approach to decarbonizing the nation’s energy infrastructure would be to improve energy efficiency in equipment and delivery systems and reduce consumption. The second would be to electrify as many cars, space heaters, water heaters, and cooktops as practical, using electricity from renewable sources. The third would be to replace as much natural gas as possible with low-carbon alternatives such as biogas, hydrogen, or synthetic gas (a liquid blend of hydrogen and ammonia or methanol designed for easy transport in existing pipelines), which combust without carbon emissions.

The gas infrastructure is old and in need of repair, but spending on pipeline maintenance above what is required for immediate safety is unwise. One strategy, beyond minimal repairs, is to select a neighborhood, convert it to a clean alternative, and then shut off that section of the gas system, thus reducing the size of the network. Another option is to develop a geothermal district. Ground-source heat pumps can tap temperatures deep underground to provide neighborhood heating and cooling. Installation costs are high, but operating costs are negligible. Gas line rights-of-way could be used for geothermal pipes.

The American Gas Association (and SoCalGas) has promised to use more biogas and create hydrogen/biogas blends. These cleaner alternatives need to be pursued, but costs are high, and scope appears to be limited to supplanting only a fraction of natural-gas use.

Reining in climate change requires many solutions. Gas utilities and the 98,000 workers employed in the gas industry need to be part of the picture. Repairing unsafe infrastructure, developing geothermal systems, and expanding renewable natural gas would use the expertise of many of these workers.

Large-Scale Carbon Sequestration Is Imperative

Combining Indigenous Wisdom, Research, and Technology Offers Carbon Storage to Scale

Nature has an uncanny ability to restore and regenerate itself. An area of forest the size of France has regrown across the world in the last 20 years with minimal or no input from humans. According to scientists, these restored forests have the potential to store more carbon dioxide than the emissions produced each year by the U.S. Despite this news, surprising to many scientists and conservationists, deforestation is still claiming vastly more forest than what is being regenerated.

Many have come to the realization that only through massive carbon sequestration will we be able to address climate change in time to keep the planet livable. One such program with a vision of large-scale carbon drawdown is called Seed the North. Located in northern British Columbia, it aims to regenerate large swaths of land, first in B.C. and then across Canada. The project’s mission incorporates three pillars: traditional Indigenous knowledge, scientific research, and harnessing the possibilities of technological innovation.

The impact of climate change can be seen in northern B.C., where forests are suffering from drought, wildfires, and pest infestations. These impacts are compounded by massive carbon unleashing through logging, mining, and fossil-fuel extraction — powerful industries in the province. Thousands of seedlings are planted every year by the forest industry but for economic value, creating fast-growing, high-yield monocultures.

Seed the North, enlisting local Indigenous communities for their knowledge of the land and as part of their workforce, collects biodiverse seedpods. When combined with biochar, made from the waste wood left behind by logging, these become biochar seed casings that optimize generation. The casings offer all the required nutrients and protect the bundles from drought and scavenging animals. With ecological diversity accorded highest consideration, many of the seeds in the bundles are not considered valuable to the forest industry but are essential to forest health, carbon reduction, and wildfire prevention. Seeds of deciduous trees (birch, alder, and Rocky Mountain maple) create fire breaks. In addition, their silvery leaves reflect the sun’s heat back into the atmosphere and provide nutrients while decomposing.

The final component, beside the biodiverse seed mixes and nutrient-rich biochar casings, is using drones to disseminate the packets. It is this ingenuity that has the potential for large-scale application. Initially, the project will target remote and hard-to-reach areas that otherwise would not be replanted. It will also focus on areas disturbed by natural events, like wildfires, floods, and landslides, as well as those impacted by industry.

Seed the North is working with the provincial government while also trying to forge links with private industry. The approach of incorporating Indigenous perspectives, increasing biodiversity, contributing to long-term carbon sequestration, and being able to go large-scale is holistic and unique. Once proven, this approach has applicability across the globe.