The Energy Cycle
Any physical object that receives radiation (energy), (1) reflects some of the radiation outright and (2) absorbs some of it causing its own temperature to rise (apologies for outrightly interjecting some physics in here, but we promise to keep it simple). Any physical object also emits its own radiation that directly varies with its temperature.
Now let us assume this object is our moon (calm down, we will land on earth soon). The moon receives radiation from the sun. It reflects some of it, absorbs the rest and emits its own. For the average temperature of the moon to be constant the radiation it receives must be equal to the radiation it reflects plus the radiation it emits on its own. The average surface temperature during the day (of the moon) reaches to 107°C as it absorbs most of the radiation and drops down to -153°C during the night as it does not receive any radiation. So why is this phenomenon not present on earth? We practically receive the same radiation from the sun as the moon. No life can exist on earth with such drastic variations. Who is our saviour?
Atmosphere – the Earth’s Protector
The atmosphere of the earth is unique and acts an object itself. So, when investigating the energy balance of the earth, we find that the atmosphere lets most of the radiation from the sun pass to the earth’s surface (apart from UV where ozone comes to our rescue) but traps the infrared radiation that is emitted back from the earth. Turns out certain molecules like carbon dioxide, water vapour, and methane absorb this radiation and increase the temperature of the atmosphere. The atmosphere thus emits its own radiation back to the earth’s surface thereby increasing the average temperature on the planet (15°C as opposed to -18°C if there was no atmosphere). Nights are warmer as the heat from the day is trapped in the atmosphere and days are colder than on the moon due to convection (warmer air where the surface is receiving more sunlight gets lighter, rises, and is replaced by the denser cooler air from the neighboring regions)
The greenhouse trio of water vapour, CO2 and CH4 are the ones keeping us alive! So we just keep pumping them out right? We should be safe as that’s exactly what we are up to.
The Carbon Cycle
Aliens are not a threat to humanity, what we breathe out daily is.
Pre-industrialization, or before we realized that coal (our long dead fellow living beings) can still be exploited for energy, the carbon dioxide cycle was as follows. All living beings let out CO2 through respiration, the algae and the plants absorb this CO2 from the atmosphere and with the help of sunlight convert it into carbon-based molecules that can store energy. Some of this energy is then used for their own survival while the rest was left for the beings that would consume them. These organisms, through respiration, released the energy to stay alive and expelled the CO2 back into the atmosphere. The vast oceans also acted as sources and sinks of atmospheric CO2 but the entire planet was always in a phase of dynamic equilibrium where the CO2 levels have been fairly constant over large stretches of time.
When living beings die, some of the carbon that is stored in their bodies sinks back into the earth to form what we call fossil fuels today. Burning them has surely spearheaded our growth due to industrialization and made our lives better. But the more we continue to burn, the more is the CO2 that is being released into the air. The earth is not even remotely prepared to absorb all of it back. Our excessive deforestation, be it for paper, livestock or infrastructure is destroying one of the largest sinks of carbon – Plants. (and also our biodiversity). Excessive fishing also is harming the balance in our oceans. Algae in oceans which also absorb vast amounts of CO2 are depleting at unprecedented rates.
Fact – CO2 levels have been oscillating between 180 and 300 ppm (part per million) for the last 800,000 years. In 2020 that number touched 413ppm and has been rising ever since we started burning fossil fuels.
So what if it increases so much? It’s only parts per million! Yes that’s true but it never touched these levels for the past 3 million years. If CO2 increases, the temperature rises, if the temperature rises, the atmosphere can hold more water vapour which is also a greenhouse gas, thus the temperature rises even more and here we are stuck in an endless cycle. Also the white layers of ice in our polar regions are one of the cleanest reflectors of sunlight on our planet, which largely contribute to maintaining the global temperatures. When they melt, less light gets reflected back and more of it gets absorbed by the earth causing the temperature to rise even more. CO2 thus has a multiplier effect on the temperature of our planet and a direct correlation has been observed.
Fact – we are 1.2°C hotter on average as compared to the 19th century.
Scientists also believe in a direct relationship between global warming and catastrophic weather events.
The Sustainable Powers of Hemp
Sure! What has hemp got to do with all this??
- Hemp is one of the fastest biomass converters on the planet. It absorbs CO2 and converts it into cellulose. Trees that take years to grow have 30% cellulose content, pale in comparison to hemp that grows in 4 months and has around 70% cellulose. Lesser chemicals are required to extract this cellulose to be used in different industries like paper, bioplastics, biopolymers etc. that drastically reduces the carbon footprint if efficiencies are achieved through mass cultivation and production. By such commercial cultivation of a high energy crop, we also have the potential to reduce our dependence on trees and forests that protect our biodiversity essential to the planet’s survival and also absorb more carbon at the same time.
- Hemp is an excellent source of biofuel. Dependency on fossil fuels too can be reduced by developing efficient biofuels which only release CO2 that was trapped by the plant very recently thereby not adding additional CO2 to the atmosphere.
- Hemp as a fibre (if extracted using sustainable practices) is much more sustainable than cotton due to its properties and lesser pesticide and water requirement. Naturally, hemp is easier on the environment as compared to synthetic fibres too (that rely on fossil fuels), thereby having a potential to cut down the carbon footprint of the textile industry too!
- Hemp seeds, due to their rich nutritional profile can eventually be a substitute for meat and dairy-based products for obtaining protein, vital unsaturated fatty etc. But how does this solve our climate crisis? Well, when we eat plants or other animals, or dairy products, the thumb rule is that we are only able to harness 10% of the energy present in them. So, for example if a plant received 100 calories, the rabbit that eats it will only receive 10, and the human that eats the rabbit would only receive 1! Instead, if a human directly receives its energy from the plant, he only takes away 1/10th of the total plants from the environment thus making the overall ecosystem more energy efficient!! (more on this in Plant based vs Animal Based Diets) Hemp seed oil can also be formulated into skin care and body care products to heal various skin complications.
- It is a multipurpose crop! The carbon and energy cycles around a piece of land where hemp is being cultivated are unbelievably efficient due to all the above reasons and the fact that the entire plant can be used for various purposes with minimal wastage is enough reason to dive into the hemp universe.
Hemp is the Solution
When all these factors combined, it is a no-brainer that large scale industrial hemp cultivation for biomass and seed output, coupled with large scale industries to develop sustainable products and supply chains out of hemp has a potential to play a critical role in shaping the future of our planet, and our survival.
The End