Passage 1

The Earth's environment is an intricate web of interconnected systems, in which the atmosphere, oceans, land and living organisms maintain a delicate equilibrium. For most of human history these interactions remained relatively stable, enabling civilisations to develop and flourish. Since the Industrial Revolution, however, the scale and intensity of human activity have altered this equilibrium on a global scale. Scientists now describe the current period as the Anthropocene, because human influence has become the dominant force shaping the planet's climate and ecosystems.

One of the most urgent environmental challenges is climate change. The burning of fossil fuels, large-scale deforestation and industrial agriculture have greatly increased the concentration of greenhouse gases in the atmosphere. Atmospheric carbon dioxide has risen by almost 50 percent since pre-industrial times. While methane is a more potent greenhouse gas per molecule, carbon dioxide remains the principal driver of contemporary global warming because it stays in the atmosphere for centuries. Consequently, average global temperatures have climbed by more than one degree Celsius, triggering more frequent and severe weather events such as heatwaves, storms and floods. Rising temperatures also accelerate the melting of polar ice sheets and contribute to sea-level rise, threatening coastal communities. Warmer ocean waters have caused repeated episodes of coral bleaching, damaging reefs and the marine life that depends on them.

Biodiversity loss is a second major environmental concern. According to international assessments, approximately one million plant and animal species are currently threatened with extinction, many within the coming decades. The primary cause is habitat destruction, as forests, wetlands and coral reefs are converted or degraded by urban expansion, agriculture and resource extraction. Overexploitation, pollution and climate change also play important roles, but habitat loss is widely regarded as the single greatest threat to species survival. Invasive species, introduced through global trade and travel, add another layer of pressure by preying on native wildlife and competing for limited resources. Although biodiversity loss may be less visible than climate change, it undermines essential ecosystem services such as pollination, water purification and soil fertility.

Pollution, especially plastic waste, has also emerged as a severe problem. Every year millions of tonnes of plastic enter the ocean, where they can persist for hundreds of years. Single-use plastics, including bags, bottles and food packaging, account for a large proportion of marine debris. Over time, these larger items fragment into microplastics, which are ingested by fish and other marine organisms, eventually entering the human food chain. Chemical runoff from farms, in addition, creates oxygen-depleted dead zones that cannot support most marine life. Perhaps less appreciated is the issue of ocean acidification. The ocean absorbs approximately 30 percent of the carbon dioxide released into the atmosphere, and this chemical reaction lowers the pH of seawater, weakening coral skeletons and the shells of molluscs. The health of the ocean is therefore intimately connected to broader climate policies.

International policy responses have been developed in recognition of these threats. The Paris Agreement, adopted in 2015, established a global framework for reducing emissions and stabilising the climate. Signatory countries committed to limiting global temperature rise to well below 2 degrees Celsius above pre-industrial levels, and to pursuing efforts to keep the increase below 1.5 degrees Celsius. Yet current national pledges are insufficient to meet these goals; emissions must decline far more rapidly than governments have so far promised. Meanwhile, renewable energy sources such as solar and wind have seen dramatic cost reductions and now offer practical alternatives to fossil fuels. However, technological innovation alone will not solve the environmental crisis. Conservationists stress that protected areas need to be expanded, better connected and effectively managed, and that consumption patterns must change if ecosystems are to recover.

Ultimately, the environment is not a separate entity from human society; it is the foundation of economic prosperity and collective wellbeing. The choices made in energy production, land use and waste management will determine whether the fragile balance of the Earth's systems can be restored. Without urgent and sustained action, scientists warn that thresholds may be crossed, with irreversible consequences for both natural ecosystems and future generations. The challenge, therefore, is not simply environmental but deeply social, economic and ethical.