Climate Change

Climate change, in simpler term, is a complex phenomenon driven mainly by human activities such as burning of fossil fuels, deforestation and agricultural activities that emit greenhouse gases into the atmosphere. Greenhouse gases such as carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) trap heat from the Sun within the Earth's atmosphere, leading to a warming effect, which is greenhouse effect.

The key factors of climate change include:

1. Burning of Fossil Fuels: The combustion of fossil fuels to generate energy, such as coal, oil and natural gas releases sufficient amount of carbon dioxide (CO2) into the atmosphere. Why? Fossil fuels, form over millions of years from the burial of photosynthetic organisms, including plants on land (which primarily form coal) and plankton in the oceans (which primarily form oil and natural gas). To grow these organisms removed carbon dioxide from the atmosphere and the ocean, and their burial inhibited the movement of that carbon through the carbon cycle. The burning of this fossil material returns this carbon back into atmosphere as carbon dioxide, at a rate that is hundreds to thousands of times faster than it took to bury, and much faster than can be removed by the carbon cycle. Thus, the carbon dioxide released from the burning of fossil fuels accumulates in the atmosphere, some of which then dissolves in the ocean causing ocean acidification.

2. Deforestation: Deforestation, in simpler word, is the cutting down of large number of trees mercilessly at one-go as a result of excessive exploitation by humans. In general, trees absorb carbon dioxide (CO2) from the atmosphere, acting as a carbon sink and produce fresh air, called oxygen gas into the atmosphere for the use of living things, for us and animals as well. Deforestation, particularly in tropical regions, cuts down the number of trees available to absorb CO2, leading the rise of the level of CO2 in the atmosphere.

3. Industrial Processes: Certain industrial processes, such as cement production and certain chemical reactions release greenhouse gases such as CO2 and nitrous oxide (N2O). Let's take a look on an example, the production of metals such as iron, steel and aluminium, are cumulatively responsible for over 5% of all greenhouse gas emissions, based on the latest figure provided by the World Resources Institute (WRI). That’s because fossil fuels must be combusted in order to heat iron ore to temperatures in excess of 1,500°C to create steel, resulting in significant emission. Meanwhile, the creation of concrete incurs another 5% of emission, due to the chemical reaction and the by-products it creates necessary to convert limestone into concrete.

4. Natural processes, which have been overwhelmed by human activities can also contribute to climate change, including internal variability, cyclical ocean patterns like El Nino, La Nina and the Pacific Decadal Oscillation and external forcings such as volcanic activity, changes in the Sun’s energy output and variations in Earth’s orbit.

5. Agricultural activities: Agricultural practices, including livestock farming and rice cultivation produce methane and nitrous oxide emission. Alteration in land use, such as urbanization and changes in agricultural practices can contribute to changes in local and regional climates. To substantiate, Dr. Rattan Lal, Professor of Soil Science at Ohio State University, has calculated that over the last 150 years, 476 billions of tones of carbon has been released from farmland soils due to inappropriate farming and grazing practices, compared with ‘only’ 270 Gt emitted from of burning of fossil fuels. A more frequently quoted figure is that 200 to 250 Gt of carbon have been lost from the biosphere as a whole in the last 300 years.

6. Waste Management: Improper waste management practices, such as open burning of waste and landfills release methane and CO2 into the surrounding. For instance, food waste, is contributing to greenhouse gases emission due to its degradation creates methane, a very potent greenhouse gas. When looking at the whole supply chain of food, from farm to table, food waste contributes to around 6 per cent of global greenhouse gases emission. Not to mention, dumpsites and unregulated landfills release leachate (contaminated water), that enters rivers, groundwater and soil which harms wildlife, marine life, and the people that live near or work on the dumpsites. Additionally, areas near dumpsites experience loss of biodiversity as natural habitats are taken over by waste, and also due to many animals ingest waste, especially plastic, which contributes to shortening their lifespans.

The cumulative effect of these activities has led to a steady increase in global temperatures over the past century. This warming trend has far-reaching consequences, including rising sea levels, more frequent and intense extreme weather events, changes in precipitation patterns, and disruptions to ecosystems and biodiversity.

Mitigating climate change requires concerted efforts to reduce greenhouse gases emission, transition to renewable energy sources, improve energy efficiency, protect and restore forests and other natural carbon sinks and adapt to the changing climate.

(p/s: Next subtopic for climate change would be the consequences and solutions. See ya!)