Environmental variables

Different aspects of climate that are projected to change over time are classified differently in different literature. They tend to be described in weather terms and their taxonomies reflect their usage. Thus polar researchers will use one set and agricultural scientists another.

This lack of consistency is reflected in the literature which uses a range of terminology to describe the dimensions of climate change, including ‘climate variables’, ‘climate change variables’, ‘climate change factors’ and ‘environmental variables’.

In the engineering area, there is no established set of climate and weather variables, with the result being that each researcher, consultant or organisation uses a collection of variables which may meet their particular requirement, but are not structured or comprehensive. Significantly, these differences in classification make comparisons difficult across reports and regions.

The BECCA Wiki uses a comprehensive taxonomy of environmental variables and key parameters that specifically allows the classification of the engineering impacts of climate change on a range of assets, resources and systems. See also discussion of the Units of measurement that apply to these different parameters.

Terminology

The following table defines the three key terms used in the BECCA Wiki's taxonomy of environmental variables.

Term	Definition
Variable category	These define the four major categories of variables that might change: Water Atmosphere Soil Biodiversity and ecosystems
Environmental variable	These are the weather or physical variables within each variable category that have an impact on infrastructure assets and systems.
Key parameters of environment variables	These are the parameters which affect the degree of impact on assets, human resources and processes, and may consist of: Mean magnitude Extreme magnitude Frequency/return period Duration exceeding a critical level Direction Consistency/gusts

The selection of these terms is based on their usefulness for infrastructure organisations as they allow individual environmental factors and their parameters to be associated directly with impacts at an asset/system level. This allows cause and effect analysis to be undertaken more easily.