From a scale perspective, the IPAT equation does not help us to identify sustainable limits regarding either individual or composite environmental impacts. It does assist in our understanding of the general factors that increase or decrease environmental impact, but not the level of impact that exceeds sustainable scale.
One of the main criticisms of the expression IPAT is that technology cannot be measured with a simple indicator like emission/GDP, since the value of this ratio depends not only on technological factors, but also on other factors which may be even more important [19].
The equation is helpful, to a limited extent, in assessing the contribution of different PAT factors to greenhouse gas (GHG) emissions.
The IPAT identity, proposed by Ehrlich and Holden (1971), disentangles the impacts of human activities on environment (I) into three factors: population size (P), affluence level (per capita consumption or production, A) and technology (impact per unit of consumption or production, T), or I ¼ PAT.
To date, IPAT applications have been limited to evaluation of a single variable measure of environmental impact, such as air pollution. For example, the Intergovernmental Panel on Climate Change has applied IPAT to studies of CO2 levels 5. The equation is helpful, to a limited extent, in assessing the contribution of different PAT factors to greenhouse gas (GHG) emissions. The report suggests that levels of GHG emissions for affluent countries increase with increases in affluence, while both population and level of affluence can be significant factors in GHG emission trends in poorer countries. Various applications have found that different types of impacts (eg whether CO2 or SO2 levels are being considered) relate differently to changes in population, affluence and technology 6.
In addition to highlighting the contribution of population to environmental problems, IPAT made two other significant contributions. It drew attention to the fact that environmental problems involved more than pollution, and that they were driven by multiple factors acting together to produce a compounding effect.
It does assist in our understanding of the general factors that increase or decrease environmental impact , but not the level of impact that exceeds sustainable scale. However, by highlighting the complex interplay among a variety of factors in creating an impact, the IPAT equation also demonstrates that there are multiple ways of reducing undesirable effects. It has been noted, for example, that different nations might focus on different factors to reduce their overall impact: more affluent countries could contribute most by reducing their level of consumption (A); many poorer countries could contribute most by reducing their population (P); and the former socialist countries could make the greatest contribution by making their technologies more efficient (T). While there is some truth to this observation, it is also true that opportunities exist in most nations to make improvements in all three factors.
The formula was originally used to emphasize the contribution of a growing global population on the environment, at a time when world population was roughly half of what it is now. It continues to be used with reference to population policy.
Even with a slowdown in growth, population is an important factor in the IPAT equation. To support more people, it will be necessary to expand living areas, which could result in the clearing of more land for housing. At the same time, there will be a growing need for resources, such as water, food and fuel.
IPAT is an equation that expresses the idea that environmental impact (I) is the product of three factors: population (P), affluence (A) and technology (T).
This equation was first proposed by two scientists named Ehrlich and Holdren in the early 1970s as a way to calculate the impact of humans on the environment.
More specifically, T represents the level of efficiency of the energy sources used and how these energy sources impact the environment. For example, the T variable can be reduced by using more energy efficient products, such as high-efficiency light bulbs and appliances.
The IPAT equation developed in the early 1970s by Ehrlich and Holdren suggests that the impact (I) of society on the environment is associated with population size (P) coupled with manner of function (f), which is shaped by elements such as affluence (A) and available technology (T). To date, most studies that have used the IPAT framework have either focused on its conceptual idea or employed it quantitatively at national and international scales. Few studies have explored the sub-national/regional scale, and none have focused on the local/community scale. This paper employs the IPAT framework for the case of Israel’s urban indigenous Bedouin society of the Negev. The paper aims to highlight IPAT’s strength in analyzing the array of internal and external factors that contribute to the making of an environmental crisis in Bedouin towns; a crisis with dire effects on public health and residents’ quality-of-life. The paper describes the current environmental situation and identifies major policy interventions and actions taken by government ministries and civil organizations. It introduces a revised and extended IPAT theoretical equation [including such elements as behavior (B), social communality (Sc) and Governmental policy (Po)] as an analytical framework for various factors associated with the Bedouin urban environmental crisis. Finally, the paper suggests new directions for intervention based on addressing the different factors contained within the human–environment impact equation.
... The motivation for the reformulating of the IPAT identity into the ImPACT form was an attempt to include consumption, or the " consumer's lever " , in terms of the economic intensity of use (Ausubel & Waggoner 2008). In this way, some of the criticism that the IPAT identity in its basic form, only including the variables population, affluence and technology, ignores behaviour choices (Schulze 2002, Roca 2002) could be overcome. However, this " consumption " , or intensity of use does not describe consumption as such, but also includes structural changes. ...
IPAT model and its variants could describe the quantitative relationships between human driving force and the environmental pressure, benefit fundamental understanding of the dynamics of coupled human and natural systems, and are regarded as effective tools in solving the environmental problems caused by the social and economic development. In this paper, the fundamental concepts of IPAT model and its variants were discussed including definitions, historical developments and the hot issues in their applications. The future research trends were put forward aiming to further expand the use of IPAT models in the sustainable development of environment and social decision-making.
In 1971, in order to demonstrate the relationships among the factors of environmental impact (I), population (P), affluence (A) and technology (T), [24] proposed the famous equation, namely Impact = Population × Affluence × Technology or I = PAT.
Human activities are the main drivers of the Earth's ecological overshoot. Due to this overshoot, the actions of today may constrain the well-being of future generations. Simultaneously, despite the great extent and increase in economic activity, human needs are not universally satisfied. There is therefore a search for economic theories that offer answers to how to combine safeguarding of human needs with staying within the planetary boundaries. Here, four alternative economic approaches are reviewed. By combining insights from these, one may start to explore new territory and future pathways out of both ecological overshoot and human injustices.