Meeting the Paris Climate Agreement goals to limit global temperature rise to well below 2°C above the pre-industrial levels and pursue efforts to limit the increase to 1.5°C primarily requires rapid, deep and widespread reductions in emissions, the report emphasized
By Salam Rajesh
In a classic example of nature recovering by itself without human intervention, passers-by along the National Highway 37 stretch of Sagolband Road from Moirang Leirak Machin up to Khwairamband Keithel in Manipur’s urban Imphal landscape can see for themselves a number of banyan trees (Ficus benghalensis) growing healthily along the southern bank of Nambul River, obviously contributing naturally to the ‘green city’ concept, and importantly towards climate change mitigation in their own natural way.
Trees belonging to the fig family, like the banyan and the Peepal (Ficus religiosa) are known to sequester carbon considerably, that is, they capture and store a good quantity of carbon in their trunks, branches, leaves and roots. Similarly, trees with large trunks and dense wood such as oaks, pines and mangroves, are also considered the best absorbers of carbon dioxide since they absorb and store a good quantity of carbon in their entire system.
This interesting-yet-apparently-unnoticed instance of banyan trees coming up on their own in the Imphal urban landscape, providing greenery amidst the grey infrastructures, is a piece of the story in the larger discussion on global warming and climate change impacts that are of serious concern and deliberation across the globe on human well-being, unprecedented weather conditions incurring losses and damages, biodiversity loss, and many other issues in the present times.
“As the impacts of climate change are taking place in real-time across the world today, the scientific consensus is becoming increasingly clear that in addition to reducing emissions and meeting our global climate goals we will need to remove CO2 from the accumulating pool in the atmosphere”.
This reflection comes from Jennifer Wilcox, Presidential Distinguished Professor of Chemical Engineering and Energy Policy at the University of Pennsylvania in her forward note for the report ‘The State of Carbon Dioxide Removal 2024’.
Carbon Dioxide Removal (CDR) process is a human activity that captures carbon dioxide (CO2) from the atmosphere and stores it for decades to millennia. There are many CDR methods, which cover a variety of ways to capture and store CO2, according to the report which also states that these various methods have different levels of readiness, potential and durability.
Every method has sustainability risks that could limit their long-term deployment, and when deployed alongside measures to explicitly address sustainability risks, some methods can provide benefits beyond climate change mitigation, the report stated.
Climate change, and global warming are mainly being driven by emissions of carbon dioxide to the atmosphere, and these emissions come primarily from human activities such as fossil fuel burning, land-use changes and industrial processes, according to the CDR 2024 report. Emissions of other greenhouse gases, such as methane and nitrous oxide, are further exacerbating climate change, the report adds.
Meeting the Paris Climate Agreement goals to limit global temperature rise to well below 2°C above the pre-industrial levels and pursue efforts to limit the increase to 1.5°C primarily requires rapid, deep and widespread reductions in emissions, the report emphasized.
On this note, similar to the reference on banyan trees as important to carbon sequestration, researchers Rob MacKenzie, Professor of Atmospheric Science, University of Birmingham and Richard Norby, Honorary Professor, Birmingham Institute of Forest Research, University of Birmingham, stressed on oak trees significantly contributing in absorbing carbon from the atmosphere through the process of photosynthesis.
Rob and Richard based their study on oak (Quercus robur) trees in a long-established forest at Staffordshire, England. Their study focused on understanding how oak trees accumulated more wood when there is more carbon dioxide in the atmosphere. They experimented by injecting extra CO2 in that forest area, by increasing the carbon dioxide levels to what would be the planetary level in the 2050s. Their finding was that when the oak trees took more of the CO2 from the atmosphere, their wood production increased by 10 percent.
Their finding demonstrated that certain tree types or species play a crucial role in absorbing carbon dioxide from the atmosphere which is critical as nature-based solution strategy for climate change mitigation measures, such as the propagation of fig and oak trees in well-planned spaces as ground-rooted action to address the pervasive issue of global temperature rise.
The CDR 2024 report particularly stressed that up to 1.5 gigaton of CO2 per year of additional mitigation through emission reductions and carbon dioxide removal is required by year 2050 to meet the Paris climate goals. However, the current scenarios while assuming that significant emission reductions are already taking place, the fact is that global emissions have continued to rise steadily, the report stated.
There is a visible gap between the proposed levels of carbon dioxide removal and what is needed to meet the Paris temperature goal, the CDR 2024 report says, while re-emphasizing that closing the gap requires scaling up carbon dioxide removal, particularly rapidly in the next decade.
It is in the thick of this global concern and intense deliberation on climate change mitigation strategies that the picture of banyan trees growing up naturally without any human intervention in urban landscape becomes significant, and important to nurture. Scientific interpretations like which Rob and Richard are experimenting with oak trees, and the propagation of mangroves in coastal countries globally, equally assumes importance in the overall effort at limiting global temperature rise by 1.5 degrees Celsius by target year 2050.
Oliver Geden et al. (2024) contributing their thoughts for the CDR 2024 report writes that, “CO2 emissions have a very long-lasting effect on the climate, causing global temperature to rise and stay elevated for millennia. Halting the rise in global temperature will therefore involve bringing emissions of CO2 down to net zero. Whereas emission reduction seeks to limit the amount of CO2 newly released to the atmosphere, CDR involves taking previously emitted CO2 out of the atmosphere”.
The assessment fairly well spells out that while finding measures to reduce carbon emissions, the thrust has to be on direct carbon dioxide removal from the atmosphere if at all the Paris climate goals are to be achieved in actuality by 2050.
The purpose and objectivity of the great Green Africa Wall is one huge ambitious project that looks at the climate issues while addressing sustainable living of the local communities. At the local scale, encouraging the growth of figs and oaks naturally and as aided regeneration in planned manner can certainly help contribute to the global effort in keeping Earth cool, green, healthy and thriving.