Environment, Energy & Global Warming: What does word frequency tell us

Yesterday I came across Culturomics, a project funded by Google. This project claims to analyze frequency of usages of words in books published in 7 languages, in the last few centuries. They claimed to have culled the data out of 5.2 million books, covering ~4% of all printed books.

Since language is our primary vehicle of communication, a trend in frequency of usage of words could become a proxy for prevailing cultural and/or social trends or so...you get the picture!

I took this tool (Ngram Book Viewer) out for a spin using some phrases that are frequently being used in the current debates on energy and global warming. Results were very interesting:

First the usage frequency of words in English language





Authors writing in English have been taking some interest in "solar energy" from 1860. Their interest peaked sharply around 1980 (the first oil crisis). However, it fell equally sharply once the crisis passed. Neither "nuclear energy" nor "alternative energy" fared any better. Note a small but intriguing interest in "global warming" back in 1900- 1910. Attention to Global Warming recently caused a sharp rise since 1980.
Interests in "environmental pollution" and "fossil fuel" have been almost going hand in hand.

Now the Russian language



Russian authors were mostly obsessed with "solar energy" and "nuclear energy". Note that the frequency of usages of these words/phrases peaked during the existence of Soviet Union and has been going down ever since! Note that the usage of the two peaked at different times. The volatility is probably due to uneven flow of literature during the communist regime.

German Authors had been talking about solar energy, off and on, since 1860. Note that they had started writing about "nuclear energy" before 1940 (writers in other languages picked it up after 1940). Interest in both nuclear and solar energy has been going up ever since 1990, with Nuclear taking the lead! Germany has been a recognized leader in both. Note also that with the exception of usage in Russian language, German authors have been using the word "nuclear energy" far more than "solar energy"!



Now the authors in Spanish language:




Spanish writers took note of "global warming" at the turn of the last century. They, like authors in other languages, used "solar energy" in 1980 (almost coinciding with Nuclear energy). However, the interest flagged off quickly??


French authors had their own take. They like everyone peaked on solar energy in 1980. However, their interest in "nuclear energy" had peaked around 1960 (much before others) and has been on the decline.



Does the usage patterns mirror the energy policy and choices made by the nations?

It may not be too hard to establish a strong correlation, if the sample of the word usage data is truly random, and, is really representative. Or we can just take Google's word for it.