How can we tackle climate change? Using activities and technologies that already exist – as Dudley Shallcross and Tim Harrison explain.
Kellermeister / pixelio.de
When learning about climate change, students and the general public can easily become despondent: if the global catastrophe is inevitable, why even discuss ways to avert it? But they should not despair: there are ways to tackle one of the most important contributors to climate change: carbon dioxide (CO2). In this article, we draw on the ideas of two leading climate scientists (Pacala & Socolow, 2004; Socolow & Pacala, 2006) for stabilising carbon dioxide emissions using technologies that already exist. We then offer some ideas on how to use the topic at school.
Figure 1 (below) shows how global carbon dioxide emissions have increased over the past 50 years and how they are predicted (based largely on changes in population) to change in the next 50 years. Carbon dioxide emissions are quantified as the mass of carbon that is emitted as CO2. If we take no action, by 2055, it is predicted that global annual carbon emissions will double to 14 gigatonnes of carbon (GtC; 1 Gt = 109 t).
and predicted levels of
carbon emissions (modelled
in 2005). Click on image to
enlarge
Image adapted from the work
of Pacala and Socolow
This will give a level of carbon dioxide in the atmosphere three times higher than that observed before the Industrial Revolution. Our planet has not had such a high level (around 850 ppm) for 30 million years, and it is predicted to cause a rise in Earth’s average surface temperature of 1 to 5 °C.
wedges could maintain
carbon emissions at current
levels. Click on image to
enlarge
Image adapted from the work
of Pacala and Socolow
Is this unavoidable? Pacala and Socolow believe not. They suggest that we try to maintain carbon emissions at their current levels of 7 GtC per year and because no one method will achieve this, they have devised the idea of stabilisation wedges.
A wedge represents an activity or technology that reduces carbon emissions to the atmosphere; the reduction starts at zero today and increases linearly until, in 50 years time, it accounts for a reduction in predicted emissions of 1 GtC per year (Figure 2).
Over 50 years, the cumulative total of one wedge is therefore a reduction in predicted emissions of 25 GtC. A combination of seven wedges would achieve Pacala and Socolow’s aim: annual emissions of 7 GtC in 2055 rather than the predicted 14 GtC.
Because the model assumes a starting year of 2005, there are now fewer than 50 years to achieve the reductions, but the concepts are just as valid.
image source: Flickr
pixelio.de
Both of these options could save more than one wedge if the number of cars in use by 2055 has been over-predicted. For example, more use of telecommunication (such as web conferencing and home working) and public transport would reduce the number of cars needed.
/ pixelio.de
Newton -Syms; image
source: Flickr
All these options are based on current technologies, and therefore some may provide even more savings as technology improves. There are also conservation options for saving wedges that do not involve modern technology:
Meister / pixelio.de
More vegetarianism and thus reduced levels of meat farming would also reduce carbon (and methane) emissions.
Carbon dioxide emissions and the measures taken to reduce them will affect the young more than their teachers or the authors, so this is an important topic for schools. It could be used for a number of individual, group or class activities.
In particular, a free board game and supporting materials can be downloaded here: http://cmi.princeton.edu/wedges
Biello B (2007) 10 solutions for climate change: ten possibilities for staving off catastrophic climate change. Scientific American. See www.scientificamerican.com or use the direct link: http://tinyurl.com/3p9h22r
or the website of Conservation International: www.conservation.org/act/live_green/carboncalc
Rau M (2011) Fizzy fun: CO2 in primary school science. Science in School 20: 24-29. www.scienceinschool.org/2011/issue20/co2
Haubold B (2011) Review of Sustainable Energy – without the hot air. Science in School 20. www.scienceinschool.org/2011/issue20/sustain
Comments
Great info
Great info