Top 5 Greatest Environmental Threats of the 21st Century

The sustainability of life as we know it on Earth depends to a great extent on the environment. Not only us, but animals, trees, and all living things depend on Earth’s resources to survive. But if humans continue to pollute and over-use these resources, they may even be destroyed entirely from this planet. Today, we’ll take a look at the greatest environmental threats of the 21st century that have the potential to alter the course of life on this planet.

Greatest Environmental Threats of the 21st Century

Climate Change

Climate change is the greatest threat to humankind
[1] Climate change is the greatest threat to humankind

While the world has been tumbling into a deadly pandemic and the Russia-Ukraine war, scientists are warning that climate change is still the greatest threat to humankind. It is causing catastrophic environmental events all over the world. Australia and the US have encountered some of the most devastating bushfire seasons ever recorded; tropical storms and weather events such as hurricanes, heatwaves, and floods are more intense and frequent than seen before; and melting glaciers and warming oceans are rising sea level – drowning the lower regions of the Earth. This list of consequences doesn’t stop here; if we don’t take immediate action, it may even lead to the extinction of the Earth as we know it.

However, even if all greenhouse gas emissions were stopped immediately, global temperatures would continue to increase in the coming years. That is why we must drastically reduce greenhouse gas emissions, invest in renewable energy sources, and stop using fossil fuels as soon as possible.


Heavy Air pollution in Tehran
[2] Heavy Air pollution in Tehran

Every year, air pollution kills 7 million people and causes many more illnesses throughout the world; polluted water sickens about 1 billion people and causes millions of deaths; soil pollution, plastic pollution, and noise pollution are also sickening and killing millions of people and other living organisms.

Burning of Fossil Fuels for electricity or transportation, overuse of insecticides, pesticides, and fertilizers, greenhouse gas emissions and chemical waste disposal from factories and industries, overuse and one-time use of plastics, dust and chemicals unleashed from mining activities, large oil leaks and spills, sulfur dioxide released into the air by volcanic eruptions are some of the reasons for environmental pollution.


Stump of illegally logged rosewood from Marojejy National Park, Madagascar
[3] Stump of illegally logged rosewood from Marojejy National Park, Madagascar

Our forests are like natural sinks of carbon dioxide and produce fresh oxygen and help control temperature and rainfall. It also helps to preserve biodiversity and prevent climate change. Currently, forests cover 30% of the land on Earth, but every hour, 300 football fields worth of forests are cut down worldwide. By the year 2030, just 10% of the world’s forests may exist, and if deforestation continues, forests may disappear in less than a century. Click here to learn more about the largest rainforests.

Deforestation is mainly caused by agriculture. The land is cleared in order to cultivate commercial crops like sugar cane and palm oil or to raise livestock. Along with wood extraction for household use as fuel or building materials, urbanization and infrastructure development like road construction also contribute directly to deforestation. Brazil, Indonesia, Nigeria, the Democratic Republic of the Congo, Honduras, and the Philippines are some of the nations with the greatest rates of deforestation.

Loss of Biodiversity and Species Extinction

Loss of Biodiversity
[4] Loss of Biodiversity

In the last 50 years, there has been a significant increase in human population, consumption, deforestation, global trade, and urbanization, resulting in humanity using more of the Earth’s resources than it can restore naturally. As a result, species and habitats are becoming extinct, threatening ecosystems by disrupting natural processes like pollination.

According to a study, the sixth mass extinction of wildlife on Earth is accelerating. And more than 500 species of land animals are on the verge of extinction and are likely to be lost over the next 20 years; the same number were lost throughout the whole of the last century. According to scientists, without human damage to nature, this rate of loss would have required thousands of years.

Food and Water Crisis

Water Crisis Around the World
[5] Water Crisis Around the World

Every day, millions of people are struggling to get their hands on the food and water they need for their survival. Increasing temperatures and unsustainable farming practices have resulted in this growing threat of water and food insecurity, making it one of the most serious environmental threats today.

With the world population expected to reach 9 billion people by mid-century, the Food and Agriculture Organization of the United Nations (FAO) predicts that global food demand may rise by 70% by 2050. Even countries like Ethiopia, Madagascar, South Sudan, and Yemen are already experiencing famine-like conditions. Not only these countries, but many countries around the world are also battling to access enough fresh water to grow food and raise livestock, two essential parts of our diet. Click here to know more about Water Crisis.

While these are some of the greatest environmental threats confronting our world, there are many more that have gone unmentioned, such as ocean acidification, waste disposal and unsustainable Waste, overfishing, urban expansion, etc. There are countless factors to consider when developing a crisis response, but it is crucial that it must be organized, realistic, and far-reaching enough to make a difference.

Check out our other articles to learn more about pollution, climate change, and other environmental issues, and comment your suggestions in the comments section as well.


Thumbnail Image: Photo by Pixabay:
1: Photo by Guillaume Falco:
2: By Mehr News Agency, CC BY 4.0,
3: By original author does not wish to be named for safety reasons - email, CC BY-SA 3.0,
4: Image by PublicDomainPictures from Pixabay
5: By Sampa - Own work, CC BY-SA 4.0,