CHAPTER ONE
ZERO CARBON: WHAT EXACTLY DOES IT MEAN?
Nowadays we hear or see the phrase âzero carbonâ on an almost daily basis, used by government departments and manufacturers in fields as diverse as house building through to the motor industry. But what does it actually mean, both in the literal sense and, just as importantly, in the real world?
Basically, zero carbon (sometimes referred to as âcarbon neutralityâ) describes a nett emissions goal, aimed at significantly reducing, and ultimately eliminating, the release of greenhouse gases (often shortened to the initials âGHGâ) that cause damage to the planetâs delicate ozone layer. Some of these gases build up and trap the radiation that should bounce off the Earthâs surface into space (the greenhouse effect, leading to global warming), while others deplete the ozone layer, leaving us exposed to harmful UV B rays from the sun.
Carbon dioxide (CO2) is recognized as the main culprit in upsetting the balance of the ozone layer, but worldwide controls are being called for on the discharge of other radiative greenhouse gases, such as methane (CH4), nitrous oxide (N2O), chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs), sulphur hex-afluoride (SF6), and perfluorocarbons (PFCs).
After water vapour in the atmosphere, over which we have little control, carbon dioxide is classed as the largest contributor to the greenhouse effect. For clarity, all greenhouse gases are given a âCO2 equivalentâ (CDE) rating, to bring their damage levels into perspective. Methane is less of a threat by volume, but its global warming potential (GWP) is said to be seventy-two times higher than carbon dioxide over a twenty-year timescale, while nitrous oxide is some 289 times higher. Certain chemicals outlined in the Kyoto Protocol are several thousand times more likely to have a long-term radiative effect, which would ultimately accelerate global warming.
Burning fossil fuels is recognized as being responsible for creating around 21 billion tonnes of carbon dioxide each year, not to mention being a chief cause behind other forms of air pollution. It is the speed with which we are upsetting the balance of nature that frightens scientists, with the eco-system unable to absorb the levels of emissions we are producing.
In the background, the sustainability question also has to be raised. Even though it is a rather different problem to global warming, our current energy policies mean the two are related. As James Zachos of the University of California recently said: âWith fossil fuels today, weâre taking what took millions of years to accumulate and releasing it in a geological instant.â
One should also bear in mind that CFCs and HCFCs, commonly found in refrigerants, aerosols and solvents, have the ability to destroy the ozone layer, as do other gases which are either man-made or occur naturally as part of the mechanism of the eco-system. We talk about the delicacy of the ozone layer, but itâs hard to imagine just how flimsy it is. To give the reader some idea of the scale, if it were compressed down to air pressure at 0ÂșC, it is only 3mm (0.12in) thick, yet it absorbs around 98 per cent of the sunâs UV B rays, protecting the planet and its inhabitants. Since the 1970s, ozone-layer depletion has been recorded at a rate of about 4 per cent every decade. Due to the unusually cold weather, ozone loss over the Arctic was so severe in 2011 that scientists reported an âozone holeâ like the one that already exists in the Antarctic.
GLOBAL WARMING
In historical terms, global warming has become a top news item only recently. The greenhouse effect has been recognized for well over a century, but it wasnât until 1974 that ozone depletion was first recognized by scientists. Even then, no one really took any notice, and as a result, the layman had never really considered it to be an issue. Now, of course, in this age of electronic communication, one is bombarded with âfactsâ citing gloom and doom, and counter-facts that tell us not to worry.
Certain governments have deliberately employed scientists to challenge established data, saying industry and current lifestyle practices are not the cause of global warming. This is simply a case of politicians pandering to lobbyists who are only interested in protecting their livelihood and short-term profit margins.
Yes, the world may be warming up naturally due to sunspot activity, and itâs easy to point out that Earth has been through phases before, which have taken us through from a world in the tropics to the Ice Age â but to ignore the damage being done by the planetâs inhabitants is foolish in the extreme. For instance, the smog that shrouds London, Madrid, Milan and Athens from time to time, as well as Mexico City and highly populated parts of California and Japan, now covers huge chunks of China on a daily basis, and is entirely of our own doing.
We may or may not be able to stop the polar ice caps melting little by little â an unlikely situation in the Antarctic, as it happens, and not really a big problem in the Arctic beyond wildlife concerns, as this is floating ice â though we definitely need to avoid the ice sheets of Greenland melting away, otherwise sea levels could rise by as much as seven metres! However, we can certainly reduce ozone-layer damage, and we can certainly make an effort to keep the air we breathe as clean as possible.
We have the tools to address the problem, but it seems that politicians often feel they have to look after those who funded their rise to power before they think of their childrenâs future. They often appear to be too selective, creating taxes that hurt the âlittle manâ in a bid to look âGreenâ on the surface, whilst happily turning a blind eye towards the real villains in the equation, coming up with wondrous schemes such as âcarbon offsettingâ, which allows...