Climate change is a hot topic. It’s all over the news, yet people don’t really have an understanding of what it is. This blog looks to clarify exactly what is happening and the causes of Climate Change.
It is the scientific consensus that the main cause of the current global warming trend is the greenhouse effect. This effect is caused when the atmosphere traps heat radiating from earth towards space. Gases in the atmosphere block heat from escaping. Certain gasses in the air cause heat to become trapped in the atmosphere.
The gasses that contribute towards the greenhouse effect include Nitrous Oxide (N2O), Water vapour (H2O), Carbon Dioxide (CO2) and Methane (CH4)
Water vapour increases as the Earth’s atmosphere warms up. With this the possibility of clouds and precipitation increases. This is called a feedback mechanism to the greenhouse effect.
Carbon Dioxide is released through natural processes such as volcanos and through human activities. The human activities that contribute to this include deforestation, land use changes and burning fossil fuels. Since the start of the industrial revolution, CO2 concentration has increased by more than a third. This is a major contributor to climate change.
Methane is produced from the decomposition of waste in landfills, agriculture and in particular rice cultivation. Other contributors to methane levels include emissions from livestock. Methane is a more active greenhouse gas compared to CO2 but is much less abundant in the atmosphere.
Nitrous Oxide is a powerful greenhouse gas that is produced by soil cultivation practices including commercial and organic fertilisers, burning fossil fuels, Nitric acid production and burning biomass fuels.
CFCs are synthetic compounds that are produced by industry. These became famous in the 1980s for their effects on the Ozone layer. They are greenhouse gasses, but their production has been limited by international agreement.
Human activities are contributing to greenhouse gas concentrations in our atmosphere. Over the last century, the burning of fossil fuels has increased the concentration of CO2 in our atmosphere. This is because the burning process combines carbon and oxygen in the air to make CO2. To a lesser extent, deforestation and other human activities have also increased concentrations of greenhouse gases.
What are the consequences of greenhouse gases?
On average, Earth will get warmer.
Warmer conditions will probably lead to more evaporation and precipitation. This will cause some areas to become wetter and some will become drier.
A stronger greenhouse effect will warm the oceans and will melt glaciers and other ice, increasing sea levels. Ocean waters will become warmer contributing to further rises in sea levels.
Some plants will benefit from higher levels of CO2 in the atmosphere, making them grow quicker and use more water. Higher temperatures and shifting climate patterns may change areas where crops grow, causing imbalances in the natural plant communities.