The Implications of Human Energy Consumption: The Anthropocene

The IPCC report suggests that in 2004, 85% of the total primary energy used was provided by fossil fuels. They have found that this value remained constant in 2007 when the new IPCC report was released. The IPCC report is a report released every few years and IPCC stands for Inter Governmental Panel on Climate Change. It is a working group of scientists that try to include everything we thus far know about climate change from the scientific point of view and make a big encyclopedia book report about it, which is released every few years. IPCC is very widely used and quoted in all sorts of industries and by other scientists and it includes predictions on future climate change too. The last big report was released in 2007 and 2004 prior to that. However a new report has just been released in the last quarter of 2014 but it is currently only available as an electronic version. Technical Summary is provided at the beginning of the 2007 report, which is what I am basing this blog post on.

Figure 1 shows the break down of where the world’s energy come from- the shares of energy sources in total global primary energy consumption in 2008. It illustrates clearly that most of the energy comes from the non-renewable resources such as oil, gas and coal and only very small proportions come from bioenergy and nuclear energy, highlighting again the above statement that 85% of energy comes from fossil fuels. The problem with this is that fossil fuels combustion accounted for 56.6% of all the anthropogenic GHG emissions in 2004. (IPCC, 2007) GHG stands for Green House Gases and includes Carbon Dioxide, Methane, Ozone, Nitrous Oxide and Water Vapor. Here we particularly focus on Carbon Dioxide and Methane increases.

Figure 1.

Source: IPCC 2007. Shares of energy sources in total global primary energy supply in 2008.

Many scientists now argue that we have reached the new geological era, known as The Anthropocene due to human impact to the environment. Our planet, The Earth itself is over 4.5 Gyr old and the last period of time is known as the Quaternary, beginning 2.6Ma ago (Zalasiewicz, 2011). It includes two epochs- The Pleistocene and The Holocene. See Figure 2 below for the geological timescale of the Earth. Holocene is the shortest epoch (it only began 11,000 years ago) and it is thought by many scientists that it has now come to its end and we are living in The Anthropocene. This is currently a big debate as to whether we have reached The Anthropocene and when exactly it has began however the evidence of climate change due to human influences is clear. Some think The Anthropocene began in 1950 which is known as the beginning of The Great Acceleration after all the World Wars have ended and humanity had access to new industrial technologies, the world economy greatly grew and developed with the world becoming very globalized, inter connected, the world trade bloomed, population tripled and so on which all required major increase of energy consumption. Some believe The Anthropocene began prior to this with the invention of steam engine and industrial revolution in the end of 19th Century whilst some believe it began even before that.

Figure 2. 

Source. Geological Timescale of the Earth. 

Regardless of when it occurred, I think it is safe to say that The Anthropocene has indeed begun, as there is plenty of evidence for it (Figure 3). Firstly the GHGs highlight the whole extent of the issue with carbon dioxide levels are now over a third higher than in pre-industrial times and at any time in the past 0.9 m.y. They are currently at 379ppm (recorded in 2005) (Zalasiewicz, 2008). From the original preindustrial value of 270-275ppm, CO2 increased to about 310ppm in 1950 with an even more rapid increase since then reaching 379ppm in 2005 (Ellis, 2011). Methane concentrations have also roughly doubled since pre-industrial times. Global temperature increases are also obvious although so far they have lagged behind the increase in GHGs perhaps as a result of industrially derived sulfate aerosols, which created the global dimming effect. However the global temperatures are in fact predicted to rise by 1.1C to 6.4C by the end of this century (Zalasiewicz, 2008). 

And whilst natural variations in the concentrations of these gases in the Earth’s atmosphere as well as climate temperatures variations are not uncommon and can be reconstructed using palaeo reconstructions, this is the biggest increase and the most rapid one The Earth has ever seen thus these changes are considered to be happening faster than those associated with glacial-interglacial transitions. The question is whether this is terminal and non reversible and is it too late to do anything about it?! Even if not, it would take a lot of convincing to stop people and governments from using fossil fuels especially developing countries with booming economies such as China and India as obtaining renewable energy is much more expensive and effort demanding and we are yet to develop technologies to make it as accessible as energy from fossil fuels. It is also a moral question as EU, USA, Japan and so on, used fossil fuels, when they were developing in the 19th, and 20^th century so why can China and India and other countries that are currently experiencing economics and development booms not do the same. Perhaps it is even impossible to cut down and swap to renewable energy until the fossil fuels have run out… As for nuclear energy, that is also risky business as major global catastrophes are possible such as Chernobyl and the one recently in Japan although a lot of countries such as France and Japan, before the Fukushima Daiichi nuclear disaster of August 2011, have converted most of their energy supply to nuclear.

Other evidence of climate change and The Anthropocene include sea level rise and also other changes in the surface ocean waters- they have now become 0.1 pH units more acidic due to anthropogenic carbon release. Sea level rise occurs firstly due to thermal expansion which happens because as the sea water warms, it expands however it takes a long time for the oceans to warm due to deep water circulation taking thousands of years to complete one cycle which means that the sea level rise is lacking behind the temperature increase we are currently experiencing due to GHGs. Secondly it also occurs due to ice melting as more water is added to the ocean and we can see this sea level rise already where it rose by 17cm over the 20th century. Further sea level rise is predicted of another 20-60cm until the end of this century if ice-melt is small or even over 1m if significant ice-melt occurs.(Tyrrell, 2011). However further sea level rise will also occur due to warming of waters but when this will occur and to what extent is unknown. There are other changes that have also occurred on Earth due to increase in GHGs and climate change but I am not going to discuss them further in this blog post.

Figure 3.
Source: Steffen, 2011. Shows evidence of anthropocene occurring.

In conclusion IPCC report clearly states that GHG emissions due to provision of energy sources for our developing world is the major cause of climate change. «The AR4 concluded that, most of the observed increase in global average temperature since the mid-20th century is very likely due to the observed increase in anthropogenic GHG (greenhouse gas) concentrations.”- IPCC, 2007. They also suggest that the reserves of fossil fuels that still remain on Earth have enormous potential to cause even higher climate change unless something is done about it. Thus whilst there is clear evidence of climate change and human impact on our planet, the main questions still remain: are we living in the Anthropocene? If so, when has it began? And is the Anthropocene «The Beginning of the End» of our planet?