Climate change is a term commonly thrown around in the media, without addressing the basic facts of climate change. This post will address two key questions. What is climate change and why is everyone talking about it?
Climate change is a global environmental problem. Defined by the United Nations (UN) as ‘a change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere, in addition to natural climate variability’1. In simple terms, climate change refers to changes in Earth’s climate over time, as a result of human actions.
Greenhouse Gases (GHGs) affect the Earth’s energy balance and climate through the greenhouse effect. This is the way that heat is trapped close to Earth’s surface by GHGs. One way to visualise this is for GHG’s to be a blanket, making Earth much warmer than it would be without them. The most ubiquitous GHGs include carbon dioxide, methane and nitrous oxide.
So, what are the main causes of for rising emissions?
Burning coal, oil and gas produces carbon dioxide and nitrous oxide. Coal is the single biggest contributor to anthropogenic climate change, responsible for 46% of carbon dioxide emissions each year2. The extraction and burning of fossil fuels, including coal, oil and gas, all contribute to climate change due to the GHGs released.
Deforestation. As trees grow, they capture and absorb carbon dioxide in Earth’s atmosphere. So when they are cut down, the beneficial effects of trees are closed and carbon persists in the atmosphere. Deforestation contributes to 15-20% of global carbon emissions3.
Increased livestock farming. Cows and sheep produce methane when disgusting food, which contributes to global warming. The sector also requires a significant amount of natural resources, the production of these resources also play a role in greenhouse gas emissions. In 2013, the UN estimated about 14.5% of global GHG emissions are associated with livestock farming each year4.
What are some of the consequences of climate change?
Climate change will cause different problems around the globe. Emission distribution is important to consider. Although developed countries are those who produce the most emissions, it is developing countries who will receive the brunt of these emissions. This is a problem known as the tragedy of the commons. The atmosphere is a shared resource and we all bear responsibility for the actions of the entire population.
Global scientific evidence for climate change:
Further evidence includes:
- Glacial retreat almost everywhere around the world.
- Shrinking ice sheets. Between 1993 and 2019, Greenland lost 279 billion tons of ice per year on average and Antarctica lost 148 billion tons per year6.
- Decreased snow cover. Less snow is falling at higher altitudes and snow is melting earlier.
- Sea level rise. In the last century, sea level rose by 8 inches. In the last two decades alone, this figure is almost double7.
- The extent and thickness of Arctic sea ice has declined rapidly over the past few decades.
- As humans emit more carbon dioxide which is absorbed into the ocean, the ocean is becoming increasingly more acidic. Ocean acidity has increased by 30% since the start of the Industrial Revolution8.
Evidence in the UK for climate change:
The UK’s 10 warmest years on record have occurred since 20025. Heatwaves are becoming much more likely due to climate change and we can expect drier summers with increasing water scarcity like that in Summer 2018. Winters are more likely to be milder but have rainfall is becoming more common so we can expect wetter winters. The winter storms of 2015 were at least 40% more likely because of climate change5. With heavier rainfall we can also expect more flooding.
What can you do?
Fortunately, there are some easy steps that you can take to minimise your environmental footprint.
- Switch to renewable energy in the home
- Drive less and use public transport
- Reduce your meat consumption
- Check your food miles! Eat products in season in the UK
- Recycle where possible
- Calculate your carbon footprint. This will inform you on the amount of greenhouse gases your lifestyle emits and the easiest areas to reduce your emissions.
For more information, refer to the WWF footprint calculator at: https://footprint.wwf.org.uk/#/.
Thank you for reading!
1 – United Nations. 1992. Available at: https://unfccc.int/files/essential_background/background_publications_htmlpdf/application/pdf/conveng.pdf.
2 – End Coal. N/A. Available at: https://endcoal.org/climate-change/.
3 – Schmidt, M. 2011. Available at: https://www.nrdc.org/experts/jake-schmidt/new-nasa-map-shows-how-much-carbon-stored-global-forests-what-risk-if-we-dont.
4 – Climate Nexus. N/A. Available at: https://climatenexus.org/climate-issues/food/animal-agricultures-impact-on-climate-change/.
5 – Met Office. 2019. Available at: https://www.metoffice.gov.uk/weather/climate-change/effects-of-climate-change.
6 – Velicogna et al. 2020. Available at: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2020GL087291.
7 – Nerem et al. 2018. Available at: https://www.pnas.org/content/115/9/2022.short.
8 – NOAA. N/A. Available at: https://www.pmel.noaa.gov/co2/story/What+is+Ocean+Acidification%3F.