Numbers and Terminology

Lord Kelvin

One of the themes of this book is that qualitative statements to do with climate change and related topics are not enough. Ideas and suggestions need to be evaluated quantitatively. In the words of Lord Kelvin (1824-1907) — whose name is used for the temperature measurement,

When you can measure what you are speaking about, and express it in numbers, you know something about it, when you cannot express it in numbers, your knowledge is of a meager and unsatisfactory kind.

One of the biggest challenges that scientists and engineers face is that many of the people with whom they are trying to communicate do not have a mathematical background. Therefore they have trouble explaining the results of their work in a way to which people can relate. For example, the word ‘error’ when used in statistical analysis has a different meaning from its normal use in general discussion, where it implies that someone made a mistake.

There is no easy answer to this dilemma. Scientists and engineers have a responsibility to communicate as best they can while minimizing their use of numbers. But those who wish to understand climate change, its implications and potential solutions also have a responsibility to follow the data and charts as best they can.

In the next chapter, there is a discussion to do with the apparent paradox that renewables are growing at a faster rate in percentage terms than either coal or natural gas. Yet renewables are not replacing fossil fuels. There is an explanation for this seeming paradox. But only by carefully evaluating the raw data to do with energy consumption can we understand the resolution. And this is not just a matter of pedantic accuracy. People who have not carried out this analysis could easily wind up making an incorrect statement such as the following.

Renewables are growing at a faster rate than other energy sources. Therefore, renewables are replacing fossil fuels.

A more accurate statement would be,

Renewables are growing at a faster rate than other sources. However, overall growth in energy consumption means that the use of both renewables and fossil fuels is increasing. Renewables are not replacing fossil fuels. They are simply providing a large proportion of the increased demand for energy.

Units of Measurement

The units of measurement used throughout this book are based on the Système international (d'unités) or SI, the modern form of the metric system.