1.2 What is environmental science?
A group of disciplines or a discipline in its own right
The term 'science' is derived from the Latin word for 'knowledge' (scientia); the term has come to mean the systematic collection of data relating to the observable universe and its constituent parts and processes. The pursuit of science involves the use of widely-accepted methods, techniques, principles and approaches including observation, identification, classification, description, analysis, experimentation, standardisation, hypothesis testing, falsification, verification and theory building. Yet 'science' is an umbrella term encompassing a wide range of branches of scientific knowledge, termed scientific disciplines and sub-disciplines, which may be categorised in various ways. The term 'environmental science' refers to a grouping of scientific disciplines that are all concerned with the physical, chemical and biological characteristics of the surroundings in which organisms live. Yet there is considerable overlap between these categories and between the disciplines themselves; hence the same phenomena (such as the earth's oceans) may be studied within physics, chemistry, biology, ecology, oceanography, marine science, geology, geomorphology, seismology, sedimentology, climatology, meteorology, zoology, ichthyology, ornithology, planetary science, palaeoclimatology, palaeoecology and many other branches of science. Broadly, however, the environmental sciences contain two main sub-groupings: the life sciences (such as biology) and the earth sciences (such as geology). Furthermore, the environmental sciences include disciplines that are focused on present-day phenomena (such as meteorology) as well as on conditions that existed in the past (such as palaeoclimatology). Yet the term 'environmental science' also has a more precise meaning: it refers to a type of scientific discipline in its own right, one in which a broad range of insights from other branches of science are brought together (synthesised) to inform the understanding and management of contemporary environmental issues.
A focus on environmental change
By its nature, therefore, environmental science is interdisciplinary. It includes activities that are descriptive (such as studies of the ranges and distributions of individual species) as well as analytical (such as studies of the factors influencing those distributions, and of the ways in which they may alter in response to environmental change). Indeed, given that the earth system is dynamic - in other words, is constantly changing at all spatial and temporal scales - and because environmental changes can have profound consequences for human societies and economies, the work of environmental scientists frequently focuses on the investigation of process and change. In fact, the task of understanding environmental change is central to environmental science - yet it is a task that may present formidable challenges, for several reasons:
- scientific knowledge is cumulative, limited and partial; many environmental changes involve parts of the earth system that are not yet fully known or understood - as in the case of the extinction of species that have not yet been formally discovered or identified
- environmental changes may be cryptic: in other words, impossible (or extremely difficult) to detect, even using modern scientific techniques - as in the case of changes that occur in the genetic material of organisms but which are not immediately apparent in the structure or behaviour of those organisms
- environmental changes may occur over vast spatial scales, making it difficult to establish effective scientific monitoring programmes - as in the case of changes in the strength or direction of oceanic currents at the global scale
- conversely, environmental changes may occur over extremely small spatial scales, again making observation and monitoring difficult - as in the case of the contamination of soils and groundwater by nanoparticles
- environmental changes may occur over very long temporal scales, including the geological timescale, and they may be imperceptible over the average human lifespan - as in the case of changes in the amount of solar radiation received due to variations in the earth's orbit
- conversely, environmental changes may be extremely rapid and their significance may not be appreciated until it is too late to conduct scientific monitoring and to establish baselines - as in the case of the collapse of an animal population following the outbreak of a virulent disease
- environmental changes may have occurred in the past when scientific monitoring techniques were not available, or were not used - as in the case of the historical rapid depletion of some whale species due to the operation of commercial fisheries
- environmental changes may involve complex environmental systems and subsystems, including myriad feedback mechanisms, and the causal relationships between the various components may not be known with sufficient certainty - as in the case of regional and local climate change due to radiative forcing
- environmental changes may have both natural and human (anthropogenic) causes, and it may be extremely difficult to disentangle the relative significance of each - as in the case of vegetation change in pastoral areas that have become drought-prone and desiccated
For reasons such as these, many concerns have been expressed about the accuracy and reliability of scientific knowledge and understanding of environmental change. Indeed, the subject of environmental change has become one of the most problematic and fiercely contested aspects of environmental science.
Environmental science is intrinsically political
It is important to emphasise a further point about environmental science: it is a subjective and value-laden activity. Despite the fact that most professional scientists attempt to use standardised, rigorous, replicable approaches and methods in their work, the pursuit of science is never truly objective. Even if scientists themselves are motivated by the highest, noblest principles, their work is produced in diverse social, political and cultural contexts that are influenced by a variety of concerns besides the pursuit of impartial scientific knowledge and understanding. At a coarse level, decisions about which scientific studies receive funding tend to reflect contemporary economic, social, political and cultural priorities. A further issue is the fact that scientific disciplines are invariably highly specialised and technical, with the result that the communication between scientists and policy-makers often falls far short of being ideal. Consequently, articulate, eminent or well-connected representatives of the scientific community are sometimes able to wield undue influence in decision-making about the allocation of research funds. Added to this is the fact that governments, corporations, industry lobby groups and other campaigning organisations sometimes devote copious resources to their attempts to influence the conduct - and even the outcome - of scientific research studies. Therefore, the pursuit of science - including environmental science - is intrinsically political and, at times, highly controversial. The political nature of environmental science has been highlighted in many international negotiations about global environmental issues, including biodiversity loss and climate change. Some people would go further and argue that environmental science contains an ethical and moral, as well as a political, dimension; such a view is typically held by those who claim that environmental science should be used to support efforts, at all scales, to promote environmental stewardship, conservation and protection. Others disagree, arguing instead that (environmental) science should be free of subjective influences, as far as possible, and should not advocate a particular viewpoint; instead, it should focus purely on the collection and communication of robust, verifiable data.