Back in 2021, the United Nations' Intergovernmental Panel on Climate Change (IPCC) report warned the world that we're headed for a climate catastrophe. The floods, fires and other extreme weather events that have devastated many parts of the planet recently are only set to become more frequent at the hands of human-induced climate change. The 2023 report echoes those sentiments, urging "effective and equitable climate action" that will "reduce losses and damages for nature and people". From farming to deforestation, fast fashion and food waste, here are the biggest ways that human beings are killing the planet.
Sadly, the world’s forests are being cut down at a rapid rate. According to experts, deforestation showed little sign of slowing down throughout 2022, despite promises made by global leaders at the COP 26 climate conference. Reports say that the world's precious rainforests lost an area the size of Switzerland over the course of last year. Since trees absorb carbon dioxide from the atmosphere, they’re an essential resource for mitigating global heating. But when they’re cleared and burned, the opposite occurs – carbon is released back into the atmosphere.
It’s hard not to be shocked by images of the Great Barrier Reef’s once-vivid corals turned white. The process, known as coral bleaching, occurs due to rising ocean temperatures, which put stress on corals so they expel the algae that provide their brilliant hues. In 2016 and 2017, the Great Barrier Reef recorded its worst-ever mass-bleaching events, which zapped the colour from more than half of its magnificent corals. Since then, a 2022 report revealed that bleaching has now affected 91% of the reefs there. The rise in sea temperatures is driven by human-induced climate change.
The use of industrial-scale fishing techniques to meet our demand for fish is depleting our oceans. For example, bottom trawl fishing is a method used in many parts of the world, whereby a large, weighted net is swept along the ocean floor to catch fish. But this can harm corals and pick up unwanted species, including dolphins and sea turtles, in a process known as bycatch. An Oceana report entitled "Taking Stock: The State of UK Fish Populations 2023" analysed 104 fish stocks and found that 34% of them were being overfished.
It’s a well-documented fact that the burning of fossil fuels is the prime culprit for climate change. When oil, gas and coal are burned, they release carbon dioxide and other harmful greenhouse gases, which trap heat in the Earth’s atmosphere and cause it to warm up. As well as being used for our energy supply, these fuels play a big role in producing plastic, steel, concrete and other important materials. Fossil fuels are currently used to supply 80% of the world’s energy.
Plastic is a double-edged sword. On one hand it’s an incredibly useful, versatile and cheap material, but on the other, it’s an environmental disaster. Virgin plastic is made from natural gas or oil, meaning it directly supports the fossil fuel industries, but this wonder-material also lasts hundreds of years without breaking down. This has led to swathes of plastic waste to accumulate in the ocean. Between Hawaii and California there’s a plastic island known as the Great Pacific Garbage Patch, which is around 617,763 square miles (1.6 million sq km).
These photos show the shocking impact of plastic on our oceans
Unfortunately, plastics aren’t the only harmful substances polluting our oceans and waterways. Sewage is one of the biggest causes of water pollution: it's estimated that around 80% of the world’s wastewater is released into the ecosystem without adequate treatment, contaminating our oceans, lakes and rivers. Contaminants from sewage deplete oxygen levels in water, which are essential to the survival of fish and other aquatic wildlife. What’s more, the pollution of already-limited freshwater supply could be detrimental to human health.
Around 83% of the world’s population lives under light-polluted skies. While there’s no doubt that artificial light has revolutionised our lives in the past century, coupled with the vast numbers of people moving to cities, the sheer quantity of artificial light is effectively stealing the night sky. Not only does this hinder our ability to see the stars, but it’s having grave consequences on plants and animals. For example, light pollution has been found to disrupt migratory birds’ flight patterns, impact animals’ sleep and wake cycles, and disturb the hatching habits of sea turtles.
When harmful gases including carbon dioxide, nitrogen oxide, sulphur dioxide and volatile organic compounds (VOCs) are released into the air, they have grave consequences on both the environment and human health. Currently, 90% of the world’s population breathes air that contains more pollutants than recommended as safe by the World Health Organization (WHO). Air pollution has myriad knock-on effects on the environment too: it contaminates soil and waterways, can lead to acid rain (due to sulphur dissolving in the air), and can lead to birth defects and diseases in animals.
Farmers around the world are increasingly using pesticides to protect their crops from being destroyed by pests. Unfortunately, however, pesticides are causing insects to die off en masse – in fact, according to a 2022 report by the Kent Wildlife Trust and charity Buglife, the UK's flying insect population has reduced by around 60% in the past two decades. Insects are essential for the proper functioning of our ecosystems, as they provide food for other species, pollinate plants and recycle nutrients back into the environment.
Another aspect of modern farming that’s wreaking havoc on our ecosystems is the use of fertilisers. While organic materials including manure and plants have been used for centuries, the invention of artificial fertilisers in the 1920s led to vast quantities of nitrogen leaking into soil and waterways. In the last 100 years, the amount of man-made nitrogen present in the environment has doubled. Excessive quantities of nitrogen not only accelerate climate change, but poison plants and animals.
Pangolins are targeted for their scales, rhinos and elephants for their tusks, turtles for their shells. Poaching might be illegal, but since these animals are so profitable on the black market, it’s still rife in many parts of the world. And it has dire consequences for the environment and puts species at risk of extinction. In Africa alone, around 35,000 elephants are killed each year. In March 2021, the African forest elephant was listed as Critically Endangered and the African savannah elephant was listed as Endangered on the IUCN Red List of Threatened Species.
Around nine to 22 miles (15–35km) above Earth is the ozone layer. In the 1970s, scientists discovered that certain human-caused chemicals, primarily chlorofluorocarbons (CFCs) used in the production of aerosols, packing materials and more, were causing the ozone layer to thin. This is bad news: ozone layer depletion means more UV radiation – which is harmful to human health – can reach Earth. Since then, those harmful substances have been banned, but now scientists have voiced concerns that the chemicals used to replace CFCs are trapping heat and worsening climate change.
It’s an unavoidable fact that each person on Earth increases carbon emissions. So the world’s burgeoning population, which is currently increasing by 80 million people per year, is a climate concern. But it’s important to note that people living in wealthy countries have had a far bigger impact on carbon emissions and most victims from climate change are from less-developed nations. In fact, according to the UN, the "global elite" produce nearly half the world's greenhouse emissions.
The process of desertification, whereby fertile land is turned to desert, has accelerated during the past century. Factors including overgrazing, over-cultivation and extreme weather events including drought have worsened the process. With as many as 135 million people expected to be displaced due to desertification by 2045, it’s one of the biggest concerns facing humanity.
Oil is a non-renewable energy source with finite reserves, meaning we can’t keep using it forever. What’s more, burning oil releases carbon dioxide into the atmosphere, worsening global warming. According to a 2022 report from the International Energy Agency, its Global Methane Tracker shows that "methane emissions from the energy sector are about 70% greater than the amount national governments have officially reported". Methane, which is responsible for around 40% of global warming, is one of the biggest by-products released when oil is burned for energy consumption.
It’s not just the burning of oil that poses a climate concern. Oil spills, which occur when oil from a rig spills out into the surrounding environment, have long-lasting ecological consequences. In April 2010, an explosion at the BP-owned Deepwater Horizon rig in the Gulf of Mexico led to the biggest oil spill in history. At its worst point, it was thought up to four million barrels of oil were leaking out into the surrounding waters per day. Despite clean-up efforts, the spill had horrific impacts on wildlife: many animals were wiped out while others continue to suffer long-standing health effects.
Although coal is relatively abundant and cheap to extract, the consequences for the environment are extremely grave. Not only does the burning of coal contribute to emissions of harmful gases – carbon dioxide, methane, nitrogen oxide and sulphur dioxide – its extraction requires the removal of topsoil which obliterates habitats and makes soil vulnerable to erosion. It’s also known to contribute to acid rain, smog and air pollution, with coal miners and communities living near mines suffering from lung diseases and other deadly health conditions.
Horrific blazes have ravaged countries across Europe and North America in the past couple of years. Scientists have warned that these wildfires, which occur naturally but have worsened due to man-made climate change, are the worst in over a decade, with the 2023 fire season sparking the EU's largest ever wildfire. Additionally, practices such as slash-and-burn – where fires are set intentionally to clear land, especially in forests including the Amazon – are directly causing forest fires. A recent study says that human activity and drought have degraded over one third of the Amazon rainforest.
While it was once seen as a silver bullet for meeting the world’s energy needs, the true environmental impact of nuclear power has now come to the forefront. To generate energy, atoms are split using mined uranium – unlike fossil fuel power plants, the process doesn’t release carbon dioxide. However, when nuclear reactors explode, the consequences are catastrophic, as the nuclear disasters at Chernobyl (1986) and Fukushima (2011) show. Thirty years after Chernobyl, it’s estimated the zone surrounding the former power plant will still be uninhabitable for 3,000 years due to deadly radiation levels. In 2016, five million people still lived in areas considered to be radioactive.
The world’s cities are responsible for around 70% of energy-related greenhouse gas emissions. Yet it’s not necessarily cities themselves that are the problem. Rather, it’s poor infrastructure and urban planning. When areas are badly connected, more people have to drive instead of taking greener modes of transport, which contributes to carbon emissions. By planning, building and managing cities more efficiently, emissions can be dramatically reduced.
It might not sound like an obvious cause for global warming, but war is contributing to the climate emergency. Warzones are often contaminated by noxious substances including uranium, oil and debris which is detrimental for wildlife. What’s more, military groups are enormous emitters of carbon dioxide: for example, if the US military were a country, it would rank 47th when it comes to emissions.
The transportation sector accounts for 24% of global CO2 emissions according to the International Energy Agency (IEA) – and road vehicles account for almost three-quarters of that total. Despite the increase in the number of electric and hybrid cars on the road, the sheer volume of travel means that overall emissions for the sector continue to rise. The sector is heavily dependent on oil, although rail travel is an exception, with 39% of its fuel supplied by electricity.
Mile-for-mile, flying is by far the most environmentally harmful way to travel. For example, a round-trip flight from London to New York releases on average 986kg (2,174lbs) of CO2 per passenger. While the sector as a whole only accounts for around 2% of global emissions, air travel is becoming cheaper and more accessible, with passenger numbers expected to continue to rise.
While a 20–30% reduction in building activity during 2020 (due to the COVID-19 pandemic) slowed the rate of emissions from construction, experts say that the industry has now since rebounded and emissions have reached an all-time high. According to the most recent findings, the industry accounts for "37% of energy and process-related CO2 emissions".
Within the construction industry there’s one particular culprit for emissions. Concrete is the most used and potentially the most destructive material on Earth. If it were a country it would be the third-biggest emitter of CO2. Despite being an essential cornerstone in creating the built world, concrete impedes the soil’s natural ability to soak up floods, making urban areas more vulnerable to destruction following these events (which are becoming more frequent and severe due to climate change). It also impedes irrigation and absorbs heat, contributing to warming in cities.
Unfortunately, when we chuck out waste it has to go somewhere. And more often than not, that’s to landfill – large sites where waste is put in a hole in the ground or on top of it. While these sites are designed to limit contamination of the surrounding environment, polluting gases including methane and CO2 are produced as waste breaks down. A substance called landfill leachate is also produced, which can pollute groundwater and contaminate drinking water supplies.
It’s not just the direct environmental implications of waste we need to consider. Food waste is a huge issue, with an estimated one-third of all food produced globally being wasted. This has wider implications for all the resources that go into our food. In the US alone, growing food that ends up being wasted uses more than one-fifth of freshwater, 19% of fertiliser and 18% of farmland. And all this when roughly 690 million people globally are still not getting enough food to eat.
Our clothes may be getting cheaper but it’s coming at a cost to the planet. Materials including polyester, nylon and acrylic are made from plastics, which not only rely on carbon to be produced, but are responsible for releasing harmful microplastics into the environment. The fashion industry also uses huge amounts of water, with one cotton T-shirt requiring an enormous 700 gallons of water to be produced. Worse still, people are only keeping clothes for half as much time before throwing them out.
It’s not just energy itself that’s harming the environment, but wasted energy. Globally, the four most-wasteful industries are: the oil and gas industry, the internet industry, the built environment and power generation. In our households, wasteful actions like leaving lights on, leaving devices on standby and overusing heating or air conditioning units are contributing to the issue of waste.
Over the past few decades, agriculture has become increasingly industrialised, which could be catastrophic for our planet. In order to rear livestock in factory farms, huge quantities of soya and other grains have to be grown and imported: in fact, almost 80% of all soya that’s grown worldwide is for animal feed. The growing of these crops creates monocultures, where patches of land that used to contain a diverse range of plants are replaced with just one, which in turn depletes soils of important minerals and nutrients. Regions dominated by monocultures are also more vulnerable to drought and flooding.
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