A third of the food intended for human consumption – around 1.3 billion tons – is wasted or lost. This is enough to feed 3 billion people. Food waste and loss account for approximately one-quarter of greenhouse gas emissions annually; if it was a country, food waste would be the third-largest emitter of greenhouse gases, behind China and the US.

Food waste and loss occur at various points in both developing and developed nations. In developing countries, a significant portion—around 40%—of food waste takes place after harvest and during processing, while in developed nations, about 40% of food waste occurs at the retail and consumer stages.

At the retail stage, a surprising amount of food is discarded due to its appearance. For example, in the United States, over 50% of produce that is thrown away is deemed "too unattractive" to be sold, resulting in a staggering 60 million tons of fruits and vegetables going to waste.

Over the past five decades, human consumption, population growth, global trade, and urbanization have expanded rapidly, leading to a situation where humanity is consuming more of the Earth’s resources than can be naturally replenished.

A 2020 WWF report revealed that between 1970 and 2016, populations of mammals, fish, birds, reptiles, and amphibians declined by an average of 68%. The primary cause of this biodiversity loss is land-use change, particularly the conversion of natural habitats like forests, grasslands, and mangroves into agricultural lands. Species such as pangolins, sharks, and seahorses are especially impacted by the illegal wildlife trade, with pangolins now critically endangered.

More broadly, a 2021 study found that the sixth mass extinction of wildlife on Earth is accelerating. Over 500 species of land animals are nearing extinction and are expected to vanish within the next 20 years—equivalent to the number lost over the entire previous century. Scientists warn that without human-caused destruction of nature, such a rapid rate of species loss would have taken thousands of years.

In Antarctica, climate change-induced sea ice melting is significantly affecting emperor penguins, with research from 2023 suggesting that entire populations could be wiped out by 2100.

In 1950, global plastic production was just over 2 million tons annually. By 2015, that figure had skyrocketed to 419 million tons, significantly contributing to the growing plastic waste crisis in the environment.

Currently, around 14 million tons of plastic enter the oceans each year, devastating marine ecosystems and the species that inhabit them. Studies predict that if no immediate action is taken, the amount of plastic pollution in the oceans could increase to 29 million metric tons annually by 2040. Including microplastics in this estimation, the total amount of plastic in the oceans could reach a staggering 600 million tons by that time.

A shocking 91% of all plastic ever produced has never been recycled, making plastic pollution one of the most pressing environmental challenges of our time. Given that plastic can take up to 400 years to decompose, its effects will persist for countless generations. The long-term consequences of plastic pollution on the environment remain largely unknown, but the outlook is concerning.

To combat this crisis, the United Nations launched a process in 2022 to create a legally binding international treaty focused on reducing plastic pollution. The initiative culminated in a meeting in Busan, South Korea, in November 2024.

The fifth round of negotiations aimed to finalize a treaty that would tackle waste management, as well as the production and design of plastics. However, the discussions ended without a conclusive agreement.

“As we adjourn these talks to 2025, it is clear that critical differences remain, and more time is needed to address these issues,” stated UNEP Executive Director Inger Andersen at the close of the meeting.

Every hour, forests the size of 300 football fields are cut down. By the year 2030, the planet might have only 10% of its forests; if deforestation is not stopped, they could all be gone in less than a century. 

The three countries experiencing the highest levels of deforestation are Brazil, the Democratic Republic of Congo and Indonesia. The Amazon, the world’s largest rainforest – spanning 6.9 million square kilometres (2.72 million square miles) and covering around 40% of the South American continent – is also one of the most biologically diverse ecosystems and is home to about three million species of plants and animals.

Despite efforts to protect forest land, legal deforestation is still rampant, and about one-third of global tropical deforestation occurs in Brazil’s Amazon forest, amounting to 1.5 million hectares each year.

Outdoor air pollution stands as one of the most pressing environmental issues today.

The World Health Organization (WHO) estimates that between 4.2 and 7 million people worldwide die each year due to air pollution, with nine out of ten individuals breathing air that contains dangerous levels of pollutants. In Africa, outdoor air pollution caused 258,000 deaths in 2017, a significant increase from 164,000 in 1990, according to UNICEF.

The primary sources of air pollution are industrial activities, motor vehicle emissions, biomass burning, and dust storms that degrade air quality.

A 2023 study revealed that air pollution in South Asia—one of the most polluted regions globally—reduces life expectancy by approximately five years. The study points to several contributing factors, including inadequate infrastructure and insufficient funding to combat pollution. Most countries in Asia and Africa, which together account for approximately 92.7% of the global loss in life years due to air pollution, lack essential air quality standards needed to implement effective policies. Additionally, only 6.8% and 3.7% of governments in these regions, respectively, provide their citizens with fully accessible air quality data.

In Europe, a recent report by the European Environment Agency (EEA) revealed that more than half a million people in EU countries died in 2021 due to health problems directly associated with exposure to toxic pollutants.

Global temperature rise has not only affected the surface but it is also the main cause of ocean acidification.

Our oceans absorb about 30% of carbon dioxide that is released into the Earth’s atmosphere. As higher concentrations of carbon emissions are released thanks to human activities such as burning fossil fuels as well as effects of global climate change such as increased rates of wildfires, so do the amount of carbon dioxide that is absorbed back into the sea. 

The smallest change in the acidity scale can have a significant impact on the acidity of the ocean. Ocean acidification has devastating impacts on marine ecosystems and species, its food webs, and provoke irreversible changes in habitat quality. Once pH levels reach too low, marine organisms such as oysters, their shells and skeleton could even start to dissolve. 

However, one of the biggest environmental problems from ocean acidification is coral bleaching and subsequent coral reef loss. This phenomenon occurs when rising ocean temperatures disrupt the symbiotic relationship between the reefs and algae that lives within it, driving away the algae and causing coral reefs to lose their natural vibrant colours.

Some scientists have estimated coral reefs are at risk of being completely wiped by 2050. Higher acidity in the ocean would obstruct coral reef systems’ ability to rebuild their exoskeletons and recover from these coral bleaching events.

Research has shown that the global food system contributes up to one-third of all human-caused greenhouse gas emissions, with 30% of these emissions originating from livestock and fisheries. Crop production also plays a role, releasing greenhouse gases such as nitrous oxide through fertilizer use.

Despite only accounting for 24% of global meat consumption, cattle ranching occupies 60% of the world’s agricultural land.

Agriculture not only occupies vast expanses of land but also consumes enormous amounts of freshwater, which is another critical environmental challenge. Arable land and grazing pastures cover one-third of the Earth's land area and together consume three-quarters of the world’s limited freshwater resources.

Experts have long cautioned that a fundamental change in our food system is necessary. Shifting toward more sustainable farming practices and embracing a plant-based diet could significantly reduce the carbon footprint of traditional agriculture.

Organic matter is a crucial component of soil as it allows it to absorb carbon from the atmosphere. Plants absorb CO2 from the air naturally and effectively through photosynthesis and part of this carbon is stored in the soil as soil organic carbon (SOC). Healthy soil has a minimum of 3-6% organic matter. However, almost everywhere in the world, the content is much lower than that.

According to the United Nations, about 40% of the planet’s soil is degraded. Soil degradation refers to the loss of organic matter, changes in its structural condition and/or decline in soil fertility and it is often the result of human activities, such as traditional farming practices including the use of toxic chemicals and pollutants. If business as usual continued through 2050, experts project additional degradation of an area almost the size of South America. But there is more to it. If we do not change our reckless practices and step up to preserve soil health, food security for billions of people around the world will be irreversibly compromised, with an estimated 40% less food expected to be produced in 20 years’ time despite the world’s population projected to reach 9.3 billion people.

Rising temperatures and unsustainable agricultural practices are exacerbating both water and food insecurity around the globe.

Each year, over 68 billion tonnes of topsoil are lost, eroding at a rate 100 times faster than it can naturally regenerate. This soil, often contaminated with biocides and fertilizers, ends up in rivers and streams, polluting drinking water and protected areas downstream.

Moreover, soil that is left exposed and depleted becomes more susceptible to erosion from wind and water due to the absence of root systems and mycelium networks that typically bind the soil together. One major factor driving soil erosion is over-tilling. While it can temporarily boost productivity by mixing in surface nutrients, tilling damages the soil's structure, leading to long-term issues like compaction, reduced fertility, and surface crusting that worsens erosion.

With the global population projected to reach 9 billion by mid-century, the Food and Agriculture Organization (FAO) estimates that global food demand will increase by 70% by 2050. Yet, more than 820 million people already suffer from hunger.

As UN Secretary-General António Guterres pointed out in a 2020 high-level meeting, "Unless immediate action is taken, it is increasingly clear that there is an impending global food security emergency that could have long-term impacts on hundreds of millions of adults and children." Guterres called for a rethinking of food systems and urged countries to adopt more sustainable agricultural methods.

In terms of water security, only 3% of the world’s water is freshwater, with two-thirds of it locked away in glaciers or otherwise inaccessible. This leaves 1.1 billion people without reliable access to water, and 2.7 billion experience water scarcity for at least one month each year. By 2025, it's projected that two-thirds of the global population may face water shortages.

The fashion industry is responsible for 10% of global carbon emissions, making it one of the most significant environmental issues today. It generates more greenhouse gas emissions than the aviation and shipping industries combined and contributes to nearly 20% of global wastewater, with around 93 billion cubic meters produced annually from textile dyeing, according to the UN Environment Programme.

Additionally, the world produces an estimated 92 million tons of textile waste each year, a figure that is expected to increase to 134 million tons annually by 2030. Much of this discarded clothing is non-biodegradable, ending up in landfills, while microplastics from synthetic fibers like polyester, nylon, and acrylic leach into the soil and nearby water sources.

Large quantities of textile waste are also dumped in developing countries, such as in Chile's Atacama Desert, where millions of tons of clothes are shipped from Europe, Asia, and the Americas. In 2023, Chilean customs reported 46 million tons of discarded clothes left to decompose in the desert.

This growing problem is fueled by the fast fashion industry, which thrives on the rapid and inexpensive production of low-quality garments to keep up with ever-changing trends. Although the United Nations Fashion Industry Charter for Climate Action has committed signatory fashion and textile companies to achieving net-zero emissions by 2050, many businesses worldwide have yet to address their contributions to climate change.

As we approach 2025, the world continues to face pressing environmental challenges that demand immediate and sustained action. Climate change remains the most significant and urgent issue, with rising temperatures, extreme weather events, and sea-level rise threatening ecosystems, communities, and economies. Deforestation, biodiversity loss, and pollution—whether from plastics, chemicals, or untreated waste—further exacerbate the crisis, disrupting natural systems and human health. Additionally, resource depletion, including water scarcity and overconsumption of fossil fuels, poses long-term threats to sustainable development.

To address these challenges, global cooperation, innovative technologies, and policy changes are essential. Mitigating climate change through the adoption of renewable energy, reducing waste, and promoting conservation efforts will be critical to preserving the planet's future. However, tackling environmental problems in 2025 will require not just top-down solutions but also widespread societal commitment and individual action to protect our planet for future generations.

Environmental problems like pollution, deforestation, and climate change can be addressed through renewable energy, conservation, sustainable practices, recycling, and stricter environmental policies.