Environmental science

Environmental science is an interdisciplinary academic field that studies the environment through an integrated application of the physical, biological, and earth sciences. Incorporating physics, biology, meteorology, mathematics, chemistry, geology, plant sciences, ecology, oceanography, and atmospheric sciences, it examines natural systems and the environmental challenges arising from both human activity and natural processes. The discipline addresses the interactions among physical, chemical, and biological components of the Earth system and seeks to develop evidence-based solutions to environmental problems.
Environmental science emerged from natural history and medicine during the Age of Enlightenment, gradually developing into a modern scientific field that investigates ecosystem processes, pollution mitigation, resource management, and the consequences of climate change. The field employs a fundamentally quantitative and systems-based approach, requiring environmental scientists to relate spatial and temporal patterns whilst solving multifaceted ecological issues.

Foundations and disciplinary scope

Environmental science encompasses a broad array of scientific disciplines unified by a focus on the functioning and health of the environment. Its interdisciplinary nature allows the integration of ecological theory, atmospheric studies, geosciences, and environmental chemistry to investigate processes ranging from nutrient cycles to climate dynamics.
Key areas include:

• Environmental chemistry, which explores the chemical composition and reactions within air, water, and soil.
• Earth sciences, covering geological processes and the formation of landforms.
• Environmental engineering, applying technological solutions to improve environmental quality.
• Atmospheric sciences, focusing on weather patterns, climate systems, and air quality.
• Sustainable systems, examining renewable resources, waste management, and long-term ecological resilience.

Environmental scientists also investigate issues such as alternative energy production, pollution control technologies, resource conservation, and the environmental impacts of industrial development. Their work frequently involves quantitative analysis, modelling, and the assessment of interactions across biological, physical, and chemical domains.

Terminology and related disciplines

Although often used interchangeably in common language, environmental science and ecology are technically distinct. Ecology is the study of organisms and their relationships with each other and with their environments. It may be considered a subset of environmental science, which additionally incorporates chemical, geological, atmospheric, and human health considerations.
Environmental science closely overlaps with associated fields:

• Fisheries, forestry, and wildlife sciences share ecological foundations with environmental science.
• Environmental studies emphasise social sciences and humanities to understand human perceptions, policy processes, and socio-environmental relationships.
• Environmental engineering concentrates on designing technological mechanisms to improve air, water, and soil quality.

The interconnectedness of these fields underscores the broad applicability of environmental science to environmental policy, conservation, and sustainable development.

Historical development: ancient civilisations

Concern for environmental issues extends back millennia and appears in historical records across numerous cultures. Early civilisations focused heavily on environmental management as it related to agriculture, water resources, and public health.
Around 6000 BCE, civilisations in the regions of Israel and Jordan experienced collapse linked to widespread deforestation. This led to early legislative measures: by 2700 BCE, Mesopotamia enacted some of the earliest known laws regulating deforestation, recognising the importance of sustainable resource use.
By 2500 BCE, communities in the Indus Valley Civilisation were manipulating river systems to improve sanitation, illustrating early applications of environmental management for public welfare. In the Western Hemisphere, several Central American city-states collapsed around 1500 BCE due to soil erosion caused by intensive agriculture, prompting survivors to adopt more sustainable land-use practices.
On the Greek island of Crete, the Minoan civilisation declined around 1450 BCE, in part due to environmental degradation and the depletion of natural resources. Early philosophical and scientific texts such as Pliny the Elder’s Natural History, composed between 77 and 79 CE, documented aspects of natural science, foreshadowing the structured study of ecological and geological phenomena.

The beginnings of environmental science: the eighteenth and nineteenth centuries

During the eighteenth century, the scientific study of the natural world accelerated. A significant development occurred in 1735 when Carl Linnaeus introduced the system of binomial nomenclature in Systema Naturae, establishing a framework for classifying organisms and identifying species based on their characteristics and environmental interactions.
By the nineteenth century, advances in physics and meteorology deepened scientific understanding of atmospheric processes. In the 1820s, investigations into the properties of atmospheric gases and their interaction with solar heat laid the foundations for climate science. Later research suggested that the Earth had undergone periods of glaciation, and scientists began to articulate the mechanisms of what is now known as the greenhouse effect, although industrial emissions were relatively low at this stage.

Twentieth-century advances and the modern discipline

Environmental science expanded rapidly during the twentieth century, shaped by technological developments, environmental crises, and growing international cooperation. Early in the century, some critics dismissed emerging climate research, but scientific interest intensified following the discovery of a notable temperature anomaly in the Atlantic Ocean during the 1940s. Post-war nuclear research also advanced understanding of carbon cycles and atmospheric chemistry, aided by archaeological evidence from ice core records that revealed historical climate fluctuations.
A decisive moment arrived in 1962 with the publication of Rachel Carson’s Silent Spring, which alerted the public to the ecological dangers of chemical pesticides such as DDT. Carson’s influential work prompted environmental legislation and inspired a generation of environmental scientists. In 1968 Garrett Hardin published The Tragedy of the Commons, highlighting the consequences of unregulated resource use.
In 1969, two major environmental disasters captured global attention: the Santa Barbara oil spill, which devastated marine life, and the Cuyahoga River fire in Ohio, caused by severe industrial pollution. These events catalysed new legislation, including the Clean Water Act and the Great Lakes Water Quality Agreement, and contributed to the establishment of the United States Environmental Protection Agency (EPA) in 1970. The first Earth Day, also in 1970, marked a global turning point in public environmental consciousness.
International developments soon followed. In 1972, the United Nations established the United Nations Environment Programme (UNEP) in Stockholm, providing a global institutional framework for addressing environmental degradation. Throughout the 1970s and 1980s, high-profile environmental crises—such as the Love Canal disaster (1978), involving residential exposure to carcinogenic waste, and the Three Mile Island nuclear accident (1979)—intensified public concern and strengthened support for environmental regulation.
The rise of environmental justice movements, exemplified by a widely recognised community-led protest in North Carolina in 1982, further broadened the field by emphasising the social dimensions of environmental risk.

Contemporary significance and applications

Modern environmental science integrates advanced analytical techniques, computational modelling, and multidisciplinary collaboration to evaluate and mitigate environmental hazards. Common areas of application include:

• Climate change analysis, examining emissions trends, atmospheric composition, and projected climate impacts.
• Pollution assessment, including water quality monitoring, air pollution measurement, and soil contamination evaluations.
• Ecosystem management, involving biodiversity analysis, conservation planning, and sustainable resource use.
• Natural hazard mitigation, such as earthquake risk analysis, flood forecasting, and preparation for extreme weather events.
• Alternative energy systems, studying renewable technologies and their environmental implications.