Watt, Where and When?

So we know what we are looking for. To establish when travel first had an impact on a global scale one has to look for increases in greenhouse gas concentrations in the atmosphere and land use change.

While there are different theories as to when humans first started having a global environmental impact, most notably from Crutzen and Ruddiman, it is the former who suggests that the invention of the steam engine was a pivotal moment. In numerous articles Crutzen argues that the anthropocene, a human dominated epoch, began in the late 18^th century when Watt invented the steam engine. In a 2003 article with Steffen he shows how different variables and indicators have fluctuated over the last 200 years as a result of human intervention. Through simple  graphs he clearly illustrate the numerous ways in which we have impacted upon the environment, and provides a representation of the ways in which humans have come to dominate nature, an idea which they have so damningly previously written about in the article.

The steam engine, however, does not mean the steam locomotive. That was not invented until 1804. As Crutzen has looked at so many indicators to establish what could constitute the start of the anthropocene what is to say that it can’t be the marked increase in train transportation in the 19^th Century; could that provide the golden spike in our geological records?

While that is tough to prove, it is without question railway mania that started in the 1840s did contribute to the increase of greenhouse gas emissions at the time, and as train travel became more established land use change accelerated rapidly as tracks were built and extended.  Between 1825 and 1837 parliament agreed to the building of 93 new railway lines, and by 1851 6,800 miles of track had already been built.  Green land diminished, residential areas were destroyed, and as the links between cities improved and the economy  strengthened, urban sprawl continued apace. Although it is most likely as Crutzen suggests that humans had already had a marked effect on the environment by the mid 19th Century, it is still interesting to think about the environemtal impacts of this railway expansion, and to what extent it did lead to global environmental change.