Highs & Lows

Humanity. It is thought to have begun about 200ka, the age of the earliest anatomical modern human ^[1]. Since this time we have diversified, multiplying in population numbers and advancing in technology, and have since become a major powerhouse on Earth. In many ways this is a good thing; our current population is over 7 billion and is still on the increase ^[2]. This means that we are thriving and our technological advancements are helping to save lives all the time - but at what cost? As our population expands, fossil fuel consumption, deforestation and nitrogen fixation, to name a few, are also on the up and these negative effects could result in self-destruction.

Will our own actions result in our demise?

Take for example the effect humanity has had on CO₂ levels. In May of this year, CO₂ levels in the atmosphere reached 400ppm at an infrared analyser on Mauna Loa. This is the first time this number has been reached in a few million years and really shows how much we are reshaping the global environment ^[3]. It is estimated by the Global Carbon Project that in 2011 ~10.4 billion tonnes of CO₂ was being expelled into the atmosphere by human activity, half of which adds to the global CO₂ levels (the other half being fixed by sinks). If our current contribution continues at this rate, we are going to miss the last stop on the global warming train.

However it’s not all doom and gloom. Global warming is well received in the scientific community and people are trying to do something about it. Particularly looking at CO₂ levels are 350.org. 350ppm is considered by experts as being the safe level of atmospheric carbon dioxide and 350.org is a movement set on solving our climate crisis. Whether it will achieve this is yet to be seen, but for it to do so it needs followers. Here’s a video from 350.org which speaks a thousand words. Watch it, think about it and sign up.

References:

[1] McDougall, I. Brown, F.H. & Fleagle, J.G. (2005). Stratigraphic placement and. Nature. 433, 733-736.

[2] Current World Population. Available: http://www.worldometers.info/world-population/. Last accessed 8th Oct 2013.

[3] Monastersky, R. (2013). Global carbon dioxide levels near worrisome milestone. Nature. 497