CLIMATE CHANGE: WHAT ARE WE TALKING ABOUT?

By SinmilOluwa Okunade

 “What’s the use of a fine house if you haven’t got a tolerable planet to put it on?”

—Henry David Thoreau

The year is 2021, you have just come out of hiding and now have access to the internet. Amongst the many things the netizens are raving about, climate change seems to be a regular. You see ads mention eco-friendly, and save the planet campaigns are a thing. The colour green is being used to describe gases and energy, things that did not have colours before you went into hiding.

Well, Welcome back! Let us start with the international headliner: Climate Change. This phenomenon that nearly everyone seems to be (rightly) agitating about is a long-term change in the average weather patterns that have come to define the Earth's local, regional, and global climates. Simply put, it is a change in the normal weather patterns of a place over a long period. Let’s say your hometown is Wasinmi, in Ogun State Nigeria, and the harmattan season usually starts in mid to late November. A change in climatic conditions might mean that Wasinmi does not experience the cold harmattan winds until January of the next year. While this is a hypothetical scenario, it closely mirrors what happened across most parts of Nigeria in 2020. Your next question might be, why would that even happen? Why would the beautiful harmattan season decide to come late?

Scientists have extensively explored and confirmed the why of climate change for decades now. While natural phenomena such as extreme weather events and volcanic eruptions, or the interactions between components of the climate system may cause the climate to vary, human activities such as the burning of fossil fuels, agricultural practices, and deforestation have accelerated the pace of climate change. According to scientists at NASA, for example, “These (aforementioned) natural causes are still in play today, but their influence is too small, or they occur too slowly to explain the rapid warming seen in recent decades.”

The main driver of climate change is the enhanced greenhouse effect. Greenhouses are glass or plastic structures where plants that cannot withstand excessive heat or cold are grown. They warm up during the day via penetration of the sun's rays which heat the plants and soil, trapping the solar energy and preventing it from leaking back into space. Greenhouse gases are naturally present in the Earth’s atmosphere, and they have a similar effect to greenhouses- they trap part of the solar radiation that reaches the Earth, ensuring that the planet is warm enough to support life. Human activities are rapidly driving up the atmospheric concentrations of these gases leading to global warming, which is a gradual increase in the overall temperature of the Earth's atmosphere attributed to the enhanced greenhouse effect.

Human contributions to greenhouse effect

Carbon dioxide emitted due to human activities is the highest contributor to global warming. By 2019, its concentration in the atmosphere had risen to 148% of the pre-industrial (before 1750) level, primarily due to cement production, deforestation, and other land-use practices. The atmospheric concentration of methane, a more potent greenhouse gas than carbon dioxide but with a shorter atmospheric lifespan has risen to 260% of the pre-industrial level due to cattle farming, fossil fuel burning, landfills, and rice agriculture. 

Nitrous oxide, which like carbon dioxide, is a long-lived greenhouse gas that accumulates in the atmosphere over decades to centuries, reached 123% of its pre-industrial atmospheric level in 2019 mainly due to increased use of fertilizers in agriculture. Fluorinated gases more popular for their role in depleting the ozone layer are also potent greenhouse gases. Although their atmospheric concentration has reduced over the past few years due to a global effort to preserve the Ozone layer, small amounts of these gases exert a powerful greenhouse effect that contributes to global warming.
In summary, the climate is rapidly changing for the worse due to human activities. Although some of these activities appear to be essential for life as we now know it, the success that has been achieved in the campaign to preserve the ozone layer has shown that change is possible if everyone acts together. However, we must approach this task with the utmost sense of responsibility that it deserves. We need to, in the words of Greta Thunberg, "… act as if the house (Earth) is on fire because it is."