Lily Hale, ELP 2013, USA/Philippines I have always been interested in carbon footprint calculations, so I attended a course in carbon footprint a couple of years ago in London, where I learned how to calculate a carbon footprint for the first time.   However, I have never put this knowledge into practice and over time have forgotten how this calculation is done.  Since attending the ELP, I have heard a few professors mention the carbon footprint, and this has renewed my interest in pursuing more in-depth the topic of carbon footprint calculations. In one of the discussions on the subject, I came across a related concept on ecological footprint calculation.  By definition, the ecological footprint is a measure of human demand on the Earth's ecosystems.   Out of curiosity, I undertook further research on the web about this new term, and, unknowingly, I was led to a site that had a test for one’s ecological footprint.   The test was designed to calculate one's ecological footprint based on one's lifestyle, and would determine one’s contribution to Green House Gas (GHG) emissions.  After a series of questions and responses, I was, to my surprise, doing quite poorly, despite my conscious efforts and inherent personality of not being wasteful.  I am proud to say that I am generally a conscientious and responsible person, as my weekly garbage disposal is considered minimal.  I make every effort to save water and electricity.  Ironically, despite all my efforts to be environmentally responsible, the result of the test was quite shocking to me: I needed 5.89 earths to support my lifestyle.  I was not expecting myself to carry a load of such a great magnitude!  Imagine those people surrounding me whom I thought maybe 10 or 100 times more wasteful, what load they would be carrying?  To project further, if everyone lives a lifestyle worse than me, this means that they require more than 5.89 earths per person. For how long a period would our planet Earth be able to carry this heavy load for the populations living on it? I think we all have to really examine ourselves before it is too late.  What can we each do to reduce our ecological footprint?  You may be surprised that there are so many things around us that are so easy to do, yet if everyone were to do it, the contribution would be enormous.  Just to name a few: turning off the lights, both in the office and at home, when lighting is not needed; unplugging all electrical plugs for all unused electronic gadgets or equipment; after washing your hands, shaking off the water before using a paper towel and trying to use only one sheet instead of multiple sheets of paper towels; or, better still, using a cloth towel instead.  The list of things that we can do to reduce contributing to GHG is long, and the good news is that it does not take much effort to do. So why not do our share to reduce our load? Returning to my original interest in carbon footprint calculation, I started assembling all relevant methodologies of calculating the carbon footprint, or, to put it differently, the undertaking of GHG inventory.  More environmentally conscious companies around the world have now started to undertake their corporate GHG inventory, as they realized their corporate responsibility to reduce CO2 emissions and the long term benefits that come with it.   With the advent of carbon tax in many countries, the trend of undertaking GHG inventories are bound to be increased.  Being one who works in the environmental arena, shouldn't we be more proactive and step ahead of the curve?