faqs

What is global warming - the Greenhouse effect

The earth's atmosphere is made up of gases that allow the suns light energy to pass though and warm our planet. Solar radiation, mostly as visible light, passes through the atmosphere and strikes the surface of the earth. A lot of the heat energy that this creates is radiated back out toward space. But as it passes back out the lower part of our atmosphere, some of the heat is trapped by greenhouse gases such as carbon dioxide. This natural process called the greenhouse effect, keeps the surface of the earth warm enough to sustain life. This is the same principal gardeners have used over the centuries within their greenhouses - hence the term "greenhouse" gases (GHG). The Earth's global mean surface temperature has increased by in between 0.4° to 0.8° Celsius over the last century.The proportion of these Greenhouse Gases has increased significantly over the last few hundred years and the scientific consensus is that the post-industrial rise in GHG does not stem from natural mechanisms.

It is actually a result of human activity.

What are we doing to cause Global warming?

It is actually a result of human activity. How? When we burn fossil fuels (coal, oil and petrol) in large quantities to power our steam engines for industry, generate electricity, heat our homes and power our motor vehicles. These activities produce four principal greenhouse gases: carbon dioxide, methane, nitrous oxide and halocarbons. The proportion of these GHG, has increased significantly over the last few hundred years and the scientific consensus is that the post-industrial rise in GHG does not stem from natural mechanisms.

What are some of the predicted outcomes due to global warming?

The increase in global temperature is causing changes in climate patterns which contribute to:
rising sea levels, more severe storms, changes in rainfall patterns, increased risk of bushfires and adverse impacts on ecosystems.
We are all facing a serious problem, not only for our generation but for the generations to follow. The effects of global warming are very difficult to predict, however are a global concern. CSIRO (Commonwealth (of Australia) Scientific and Industrial Research Organisation) predicts that, relative to 1990, average annual temperature in Australia may increase by 0.4° to 2° C by 2030 and by 1° to 6° Celsius by 2070.

Global warming may cause regional rain patterns to change (both within Australia and around the world), while melting glaciers and the thermal expansions of seawater may raise global sea levels by between 15 and 95 cm by the year 2100 (with a current 'best estimate' of 50 cm).

The possible effects of climate change on Australian wildlife are yet to be fully documented, but several species are believed to be threatened, including the endangered Mountain Pygmy Possum which could, scientists predict, lose its entire alpine habitat with just a 1.0 C rise in mean annual temperature. It also appears that many corals in the Great Barrier Reef are living close to their survival limits in terms of sea temperature.

What are the different types of carbon credits?

Carbon credits are created for both mandatory and voluntary schemes. In Australia there is the Federal Mandatory Renewable Energy Target (MRET) Scheme which relates to the electricity generation sector. This scheme generates Renewable Energy Certificates (REC's).

The NSW Greenhouse Gas Abatement Scheme (NSW GGAS) was one of the first mandatory GHG emission trading schemes in the world. Increasingly it is being used by businesses and people who want to voluntarily offset their GHG emissions. Credits generated within this scheme are known as NSW Greenhouse Gas Abatement Certificates (NGAC's) and are subject to strict compliance regulations aligned with the Kyoto protocol.

Renewable Energy Certificates - RECs

One REC is the equivalent to 1MWh of renewable energy generation from sources such as wind, solar, geothermal, biomass and some hydro generation. These certificates generate carbon credits as the alternative source of this electricity would be from fossil fuels which would emit carbon dioxide into the atmosphere.

NSW Greenhouse Gas Abatement Certificates (NGAC's)

There are currently three types of NGAC's

1 Energy Efficiency
Carbon credits can be generated by reducing energy used by employing better processes or technologies to generate the same output.

2 Bio-sequestration
Instead of preventing carbon emissions, these credits are generated from the absorption of carbon dioxide by plants through the process of photosynthesis.

3 Methane destruction
Methane is over twenty times more potent a greenhouse gas than carbon dioxide. Methane generated by the decomposition of organic matter (eg in landfill) is burned and often used to generate electricity. Carbon credits are generated as methane is stopped from entering the atmosphere. Carbonreverse will use REC's or NGAC's generated by methane seam destruction to offset your carbon dioxide emissions.

Some information in this FAQ section has been provided with thanks from Carbon Planet's Carbopedia.