Environmental issues can vary in their geographical scale of impact from the individual, to the local, to the regional level, and to the global level.
- Individual Impact: A coal plant in a particular location might cause an employee of that plant respiratory problems from pollutants.
- Local Impact: Pollution emitted to nearby waterways could impact the local water systems, and cause environmental damages and human health problems.
- Regional Impact: The air pollution in the plant could travel large distances and contribute to regional acid rain deposition, damaging regional ecosystem stability.
- Global Impact: Greenhouse gases produced by the plant could contribute to global climate change.
Environmental issues can also vary in their temporal impact.
EXAMPLEAn industrial plant could improperly manage their heavy metal waste and dump high levels into local water systems. People drinking that water might experience immediate effects such as stomach irritation and dizziness. Over time, drinking that water with heavy metals could, decades later, lead to various forms of cancer in the local population. Generations of impact could result as the heavy metals damaged local marine ecosystem so severely that fish populations wouldn't be able to recover for 50 to 150 years, which would also affect local economic fisheries.
A majority of environmental problems are long-term processes, which makes them difficult to address, because humans are usually concerned with short-term needs, and have a hard time understanding long-term time frames. Addressing long-term environmental issues is also challenging because popular media only focuses on environmental issues in the short term, and policymakers tend to be concerned in the short-term duration, usually for the times of their serving term or possible re-election.
Not all environmental impacts are equal, and the degree of impact will vary depending on the type of ecosystem being affected. This is because certain ecosystems provide more or less ecosystem services, or are more vulnerable to human impacts than others.
EXAMPLEWetlands provide a large amount of ecosystem services such as biodiversity and natural water treatment. They are also more vulnerable to impacts.
Human population density is also a factor. A more densely populated area impacted by environmental damages is more significant than a less populated area because more people are involved.
EXAMPLEConsider accidental poisoning of water sources for New York City versus Poultney in Vermont. Which would be considered more impactful?
The economic status and interests of the human population impacted are other factors. Developed and developing nations can have different environmental concerns relative to their people. In addition, environmental issues tend to affect developing and developed nations differently because of economic resources and population density.
EXAMPLEConsider a drought in India versus the United States. The U.S. has a much smaller population versus its economic wealth compared to India. The result is that if both countries experienced a drought of similar severity at the same time, the degree of impact would be much greater for India because it has less economic strength to draw on.
Source: Adapted from Sophia instructor Jensen Morgan