Whatever is known about these problems is available to scientists everywhere, although the information may be incomplete or ambiguous. The knowledge relevant to environmental decisions usually varies by time, place and circumstances. Specific knowledge, by contrast, varies by location and circumstance and may change over time. Specific knowledge also embraces such matters as the subjective valuations of individuals. Often, knowledge relevant to environmental decision making is specific.
Most environmental impacts occur locally.
Impacts vary depending on local geology, hydrology, biology and meteorology. While universal knowledge in the form of scientific theorems provides some uniform understanding of the physical world, specific knowledge of each location is what enables understanding of actual environmental harms and potential remedies. Most environmental problems also have a dynamic dimension. Impacts change over time, depending on many interdependent, location-specific variables. For example, all resource uses involve dispersed, dynamic and interdependent supplies of materials.