Author Archives: Eann Patterson

70,000 trees needed

‘70,000 trees needed to print graduation papers’. This was a headline that I spotted in the China Daily (Thursday 24th April, 2014) while I was travelling in China last moth. The article reported that the trees would be cut down to provide the graduation papers for this year’s 7.27 million university graduates in China. Superficially, these are very large numbers, both of trees and graduates. However, China has a population of 1.38 billion, which is almost 20% of the global population, so the annual graduation rate is only about 0.5% of the population compared to about 1% in England. There are concerns in China that there are insufficient graduate-level jobs for all of the students graduating this year, which is a familiar situation in the UK. The idea of following the Finnish approach to higher education, with more universities of applied sciences than multi-disciplinary universities, is gaining ground in China. In the UK, EngineeringUK has estimated the number of engineering graduates needs to double by 2020 in order to sustain our engineering industry whose turnover was £1.1 trillion in 2011-12, or 24.5% of UK turnover. The shortage of engineering graduates is reflected in average starting salaries that are 20% higher than for all graduate.

Back to those 70,000 trees; they would absorb between 2 and 20 kg of carbon dioxide per tree per year if they were not felled for the graduation papers. Carbon dioxide sequestration by trees depends on their size, age and species, see for example the sources below. The CO2 emissions in China are currently about 7 tonnes per capita, which is about the same as the UK and about 40% of the per capita emissions in the USA, according to the EDGAR or the World Bank, so that means that 70,000 trees might balance the emissions of between 20 and 200 graduates, i.e not many of the 7.27 million!

Sources:

http://www.forestry.gov.uk/pdf/6_planting_more_trees.pdf/$FILE/6_planting_more_trees.pdf

http://www.nature.com/news/carbon-sequestration-managing-forests-in-uncertain-times-1.14687

http://sustainability.tufts.edu/carbon-sequestration/

Lost at sea

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Loading our shipping container to leave USA

Our inability to find flight MH370 was still very prominent in the national media when I was in China last month. The search for the aircraft and the false alarms caused by floating rubbish at sea has raised awareness about the amount of junk floating around our oceans, for instance 10,000 shipping containers are lost at sea every year, or more than 1 every hour. However, there are about 17 million containers in the world, so we only lose about 0.05% per annum which is a negligible amount unless its the one containing all your household goods as you move continents!

I was interested to find a high level of environmental awareness in China. Alongside the reports on the search for flight MH370 the China Daily had a centre-page spread on Thursday 24th April, 2014 about ‘How pollution affects marine life’ with a focus on the garbage patches in the Pacific and North Atlantic oceans. The North Atlantic Garbage Patch is more than 100 kilometres in diameter with about 200,000 pieces of debris per square kilometre trapped in the gyre. These are big numbers and if you break it down to small areas then it is one piece of debris per five square metres, which a box 2.24 x 2.24m or 7 x 7 ft. This doesn’t sound so bad until you consider the impact on wildlife, for instance 86% of all sea turtles are affected by entanglement or ingestion of marine debris and an autopsy on a sperm whale found dead in Spanish waters concluded that the cause of death was ingestion of 24 meters of plastic. About 300 million tonnes of plastic are produced globally per year of which it is estimated about 6 million tonnes (2%) ends up in the oceans, with 80% being washed into the sea from rivers or blown by the wind from rubbish dumps.

The second law of thermodynamics [see my post on June 5th, 2013 on Impossible Perfection] limits the efficiency of all processes with the result that engineers are used to not worrying about losses of 10% or less so that the losses to the ocean of 0.05% and 2% mentioned above would be considered negligible but the enormous scale of human processes mean that the losses are having a significant impact on the fauna of the planet. Engineers need to lead society towards a more harmonious and protective relationship with the rest of the planet.

Source: http://www.billiebox.co.uk/facts-about-shipping-containers/