What Actually is Climate Change?
After all the comments about how “the sun controls the climate” and “it’s just the weather” I realised we might be in need of some revision!
Climate change is a topic we hear about a lot but do you really know what it means?
Contrary to what climate deniers will tell you, climate change is different from the weather. Weather refers to daily conditions - short-term changes in the atmosphere. According to NASA, weather includes occurrences such as sunshine, rain, cloud cover, wind, snow, flooding, thunderstorms, heat waves and more. On the other hand, climate refers to the average weather conditions over an extended period of time (30+ years). Discussions on climate can include averages of precipitation, temperature, humidity, sunshine, wind velocity, etc. Thus, climate change is any change to our climate over an extended period of time.
We know that our climate is changing dramatically from extensive ocean and air temperature records which show that our earth is becoming drastically hotter. The global average temperature has already risen by 1.1°C since before the Industrial Revolution. Although this doesn’t sound like a lot, it is the equivalent of four Hiroshima bomb detonations per second!
We also know that these changes are man-made, i.e. not natural! Although the climate has changed naturally in the past, scientists have reached the consensus that these changes are consequences of our actions. These changes are also happening at a much faster rate than previous changes to the climate.
To break it down further, it is true that many greenhouse gases (such as water vapour, carbon dioxide and methane) occur naturally and that it is necessary to have the greenhouse effect to an extent to keep us warm. However, since the Industrial Revolution, there has been a massive increase in deforestation, landfill and producing/burning of coal/oil/gas on a large scale. These gases are then all trapped in our atmosphere causing the Earth’s temperature to rise to unprecedented levels. Studies show that CO2 levels have increased by more than 45% since the Industrial Revolution and that CO2 levels today are higher than at any point in the past 800,000 years. We have actually altered the chemical composition of the atmosphere through this build-up of greenhouse gases!
Knowing that the climate is changing is important as it affects people across the entire world. With increasing temperatures, we can expect sea levels to rise, changes in precipitation, alterations to forests, crop yields, and water supplies, and adverse effects on health and ecosystems. These consequences are permanent and very serious alterations to our world. Some ways that climate change will affect us in Australia is an increased frequency/severity of extreme weather events (something that we are already seeing!), rising sea levels, impacts on ecosystems through habitat changes resulting in extinction and health impacts. This will also have flow-on effects such as agricultural impacts and increased pressure on emergency services.
What can be done? We need our governments to commit to a net-zero target of 2030, not 2050! To stay under 1.5°C warming, and prevent the worst effects of climate change from becoming irreversible, the IPCC has told us that we only have 7 years to transition from fossil fuels. Yet, something really important to note is that if we stopped all emissions today, temperatures would still continue to climb. We need to reverse global warming to sustainable levels and to do this we need governments to invest in technology that can do so.
I hope this provides you all with a brief explanation of what climate change actually is and encourages you to take a deep dive to find out more!
What other topics would you like us to break down?