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Unit 6: Environmental Impacts

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    The human presence and impact on this Earth has been changing with our population, technology, and affluence. In order to start understanding how these variables have an impact on Earth (in a general sense) the IPAT equation was created. As is the case for any equation, IPAT expresses a balance among interacting factors. It can be stated as:

    \[I = P \times A \times T \nonumber\]


    • "\(I\)" represents the impacts of a given course of action on the environment
    • "\(P\)" is the relevant human population for the problem at hand
    • "\(A\)" is the level of consumption per person
    • "\(T\)" is impact per unit of consumption. Impact per unit of consumption is a general term for technology, interpreted in its broadest sense as any human-created invention, system, or organization that serves to either worsen or uncouple consumption from impact

    The equation is not meant to be mathematically rigorous; rather it provides a way of organizing information for a “first-order” analysis. To achieve meaningful reductions of human impact, there are intense debates on where the focus should lie. Where one group sees expensive remedies with little demonstrable return, another sees opportunities for investment in new technologies, businesses, and employment sectors, with collateral improvements in global and national well-being.

    This unit will investigate variables that represent the biggest modern components for human impact at local and global scales. Specifically, it will focus on solid waste, pollution, and climate change.


    Modified by Rachel Schleiger from Sustainability: A Comprehensive Foundation by Openstax (licensed under CC-BY)

    Thumbnail: "Oil spill cleanup program" Is in the Public Domain

    This page titled Unit 6: Environmental Impacts is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by Melissa Ha and Rachel Schleiger (ASCCC Open Educational Resources Initiative) .

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