Climate Change

Geological history and simple science tell us that the temperature and thus climate is strongly correlated with the compost ion of the atmosphere.

The world's carbon cycle is out of balance and the atmospheric increase in CO2 has amounted to over 30% since the beginning of the industrial revolution. The climatic affects of this change are now evident and the trend must be reversed to ensure a sustainable future.

According to the Committee on the Science of Climate Change, 2001, National Research Council, USA "Greenhouse gases are accumulating in Earth's atmosphere as a result of human activities, causing surface air temperatures and subsurface ocean temperatures to rise. Temperatures are, in fact, rising."

The Correlation between Temperature and Carbon Dioxide Concentration in the Vostock Ice Cores[1].

That some gases, including water vapour, methane and carbon dioxide cause a "greenhouse affect" is irrefutable science, without the "greenhouse affect" we would all freeze to death.

The rate of temperature change is currently at least twenty times that of previous warming periods between periods of glaciation and this should be enough to convince the most ignorant of critics that our something has changed compared to past geological history. What has changed is us. There are just far too many of us and our activities on the planet are in some way causing climactic perturbation. The culprit is known to be greenhouse gases and the correlation between the level of carbon dioxide in the atmosphere and temperature is very good over the last 450 thousand years. The level of carbon dioxide in the air is now close to 390 ppm and was only around 280 ppm when James Watt invented the steam engine. Prudence would dictate that we should be cautious and consider the implications of consuming such a high proportion of the worlds fossil carbon as we have increased the level of carbon dioxide (CO2) in the atmosphere by roughly 50% in just a few short years since the beginning of the industrial revolution. The concentration will continue to rise unless we take drastic action and global temperatures will follow resulting in significant climate change.

While a very small pocket of mostly economists and one or two scientists remain unconvinced that climate change is being at least partially caused as a result of human intervention, most scientists are now talking about how much warming the Earth can withstand without catastrophic change such as the polar icecaps totally melting. The consensus is that the world may be able to cope with a two-degree rise in temperature from what it was around 1750. As temperatures have already risen by 0.6 degree C, anything above a further 1.4 degree C rise could be disastrous!

The problem is that even if we just stopped using energy from today onwards, we're already in trouble. Although it is difficult to predict future warming because of the large time lags between emissions and changes in climate, Britain's Hadley Centre for Climate Prediction and Research think that warming is already inevitable even if we stopped using fossil fuels. They predict that global temperatures will rise 0.5 degrees C from now to 2100 because of what we have already done, stabilising hundreds of years later at 1.6 degrees. This is because carbon dioxide lasts for between 50 and 200 years in the atmosphere.

In the past 50 years there have already been significant changes due to the rise in average temperatures. The Arctic icecap has already lost an area the size of Tasmania since 1970 and the sea level has risen by at least 13 cm compared to an important benchmark recorded in 1841 at the Isle of the Dead which was part of a penal settlement in that same state where TecEco are based.

Recent reports have shown that melting of the polar caps is accelerating. The director of the British Antarctic Survey, Chris Rapley is reported to have said that "the giant is awakening" and that three ice streams were speeding up and discharging into the sea on the west Antarctic ice sheet raising the prospect of a more rapid sea-level rise.

Last year's Arctic Climate Impact Assessment study found that the North Pole was warming at twice the rate of the rest of the Earth. Some models in the report predicted the near disappearance of summer sea ice by the end of this century. Around the planet at least 100 animal species are on the move, searching for cooler habitats. Polar bears and some seal species that have nowhere to go would be pushed towards extinction.

It is not only animals feeling the heat. Many human communities face evacuation including peoples living on low lying islands in the pacific or in large areas of Holland and Belgium known as the "low" countries. According to a report part-authored by the World Health Organisation and presented to an international climate change conference in Exeter, Britain on the 1st to 3rd February 2005, the "modest" climate change we have seen since the 1970s has claimed 150,000 lives a year through disease, malnutrition and heat waves.

There were other frightening predictions. The world's oceans are slowly turning acidic after absorbing about half the 800 billion tonnes of carbon dioxide humans have put into the atmosphere. If this occurs there will be a collapse in the food chain as "the whole composition of life in the oceans will change".

Although the Bush White House continues to downplay the urgency of global warming, some parts of the Bush administration have recognized the gravity of the situation. A report released in 2004 by the Pentagon's Office of Net Assessments said that by 2020, climate change could unleash a series of interlocking catastrophes including mega-droughts, mass starvation and even nuclear war as countries like China and India battle over river valleys and other sources of scarce food and water.

Australia is especially vulnerable because the country is drought prone and the environment, including the great barrier reef, tropical rainforests and Kakadu, fragile. According to scientific papers produced by the CSIRO, a few degrees of warming would cause coral to die, snow cover to decrease, agriculture to suffer and the Murray-Darling Basin, the nation's food bowl, to suffer a drop of 12 to 25 per cent of its river flow.

Modeling has shown that with a two- to three-degree increase, 97 per cent of the Great Barrier Reef would be bleached every second year. Large losses in pasture growth and livestock carrying capacity as the result of less rainfall would occur in southern Australia, while the nation's already languishing water resources would become even more scarce.

Scientists think that the temperature rise can be limited to two degrees as a result of a 50 per cent cut in global warming emissions by 2050. More recently the Stern Report confirms the economic urgency (See newsletter 64). Now is the time for action.

The Built Environment and Climate Change

If earth is viewed from outer space what can be seen of our activities is the built environment. Because of the shear size buildings and infrastructure have a profound affect on global warming. According to the Stern report[2] ”Buildings account for 8% of greenhouse gas emissions, or 20% if upstream emissions are included.”

TecEco believe the key to reversing global warming is to mimic nature and to use carbon to create our built environment thereby removing it from the atmosphere. Gaia Engineering involves the production of man made carbonates for construction and in this manner geomimics nature where carbon is essential for all aspects of life.

The main material used to construct the built environment is concrete and the manufacture of Portland cement requires considerable energy and results in chemical release of carbon dioxide. Total emissions are roughly one tonne of CO2 per tonne of cement produced[3] Portland cement production, and hence CO2 emission, are currently in the order of 2 billion tonnes.

Cement Production = CO2 Emissions, 1926 to 2004 (2004 estimated at just under 2 billion tonnes)[4].

Concrete is the most used material on the planet after water and is arguably already a relatively sustainable material. Because of the high volume used however it is still a major contributor to global greenhouse gases. Total anthropogenic emissions are in the order of 20 billion tonnes[5] and the CO2 that is produced during cement production accounts for around 10% of this. TecEco propose radical changes to the way cement is made and used in concrete to make the material much more sustainable and our lead product, Eco-Cement, sets by absorbing CO2 and is either carbon neutral or a sink depending on the method of manufacture.


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[1] Hansen, J., S. Makiko, et al. (2007). "Climate change and trace gases." NASA Goddard Centre.

[2] Stern, S. N. (2007). "The Stern Review on the economics of climate change." Retrieved 05 March 2007, from http://www.hm-treasury.gov.uk/independent_reviews/stern_review_economics_climate_change/stern_review_report.cfm.

[3] Pearce, F. (1997). "The Concrete Jungle Overheats." New Scientist(2097):14.

[4] USGS(2004). "Cement Year Book" http//minerals.usgs.gov/minerals/pubs/commodity/cements/cemenmcs04.pdf

[5] Haughton, R. (2004) "Understanding the Global Carbon Cycle" Woods Hole Institute. www.whrc.org/science/carbon/carbon.htm.