HEMP BY ALEX FULLERTON, HEMP SAVE THE WORLD
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and Other Carbon Dioxide Removal Strategies
lobal warming and climate change may be the most challenging threats the human species has ever faced. This demands a unified, focused, and organized effort from all of us around the world to transition to a net zero carbon economy and reducing the amount of carbon dioxide in the atmosphere.
of 415 ppm as of December 31, 2020. To put this into context, based on ice core records of the past 800,000 years, CO₂ concentration in the atmosphere ranged from about 185 ppm during ice ages to 300 ppm during warm periods. The concentration of atmospheric carbon is at an unprecedented level that hasn’t been observed in at least the last 800,000 years. We are in a climate crisis.
ANTHROPOGENIC CLIMATE CHANGE
REDUCING ATMOSPHERIC CARBON
Since the late 1800s, scientists have suspected human-produced (anthropogenic) changes in atmospheric greenhouse gases would likely cause climate change. In 1856, Eunice Foote discovered the heat-trapping properties of water vapour, carbon dioxide, and air when heated in the sun. These properties were further identified by Irish physicist John Tyndall in 1859. The current observed trend in global temperatures cannot be attributed to natural climate change. In fact, scientists can only account for recent global warming by including the effects of human-caused greenhouse gas emissions, which have increased since pre-industrial times due to the burning of fossil fuels compounded by population growth.
FOCUSED ON CARBON DIOXIDE How each greenhouse gas contributes to the greenhouse effect depends on three main factors: how much is in the atmosphere, how long they remain in the atmosphere, and how strongly they impact the atmosphere, measured in global warming potential (GWP). For example, methane’s 20-year GWP is 56 times that of CO₂, and its 100-year GWP is 21 times that of CO₂. However, CO₂ has an atmospheric lifetime of 300-1,000 years compared to 9-15 years for methane, and there is about 200 times more CO₂ in the atmosphere than methane. Pre-industrial levels of atmospheric CO₂ were approximately 278 parts per million (ppm), compared to the daily average
In its special report Global Warming of 1.5˚C, the Intergovernmental Panel on Climate Change (IPCC) asserts the most catastrophic effects of climate change could be averted by limiting global warming to 1.5˚C. The report describes ways of achieving this—all of which depend on removing carbon dioxide from the atmosphere. To achieve this goal, organizations around the world need to become either “net zero” or “carbon negative.” Net zero, also called “zero-carbon” or “carbon neutrality,” means carbon emissions emitted by day-to-day operations are either zero or offset by investing in initiatives certified to remove carbon dioxide from the atmosphere. Carbon negative, also called “climate positive,” means company day-to-day operations go beyond achieving net zero carbon emissions and actually remove carbon dioxide from the atmosphere. Carbon emissions can also be eliminated from the source by means of government initiatives, such as carbon taxes, carbon markets, electrifying transportation, decentralized micro-grid power generation, and more. However, since the CO₂ already in the atmosphere can affect climate for hundreds to thousands of years, we must not only transition to a zero-carbon economy, we must also implement carbon dioxide removal (CDR) strategies on a massive scale.
CARBON DIOXIDE REMOVAL STRATEGIES A variety of CDR strategies has used at large scale for decades and more are on the horizon in different stages of development. Each strategy has pros and cons, varying in cost, benefits, and risks.