Climate+Change

**An introduction - what is it all about?**
 * Climate Change **

media type="youtube" key="8m-80cq8Q5A" height="390" width="480"

**What are the potential costs associated with climate change for Australia?**

**Source:http://www.garnautreview.org.au/chp6.htm**

If global development continues without effective mitigation, the mainstream science tells us that the impacts of climate change on Australia are likely to be severe. For the next two decades or so, the major impacts of climate change are likely to include stressed urban water supply and the effects of changes in temperature and water availability on agriculture. All major cities and many regional centres are already feeling the strain of declining rainfall and runoff into streams. Most major cities are beginning to develop high-cost infrastructure for new water sources. In the absence of effective global mitigation, continued investment in expensive new sources of water is likely to be a necessity. By mid-century, there would be major declines in agricultural production across much of the country. Irrigated agriculture in the Murray-Darling Basin would be likely to lose half of its annual output. This would lead to changes in our capacity to export food and a growing reliance on food imports, with associated shifts from export parity to import parity pricing. A no-mitigation case is likely also to see, by mid-century, the effective destruction of the Great Barrier Reef and other reef systems such as Ningaloo. The three-dimensional coral of the reefs is likely to disappear. This will have serious ramifications for marine biodiversity and the tourism and associated service industries reliant on the reefs. By the close of the century, the impacts of a no-mitigation case can be expected to be profound (see Figure 6.2). The increased frequency of drought, combined with decreased median rainfall and a nearly complete absence of runoff in the Murray-Darling Basin, is likely to have ended irrigated agriculture for this region. Depopulation will be under way. Much coastal infrastructure along the early 21st century lines of settlement is likely to be at high risk of damage from storms and flooding.

What are the costs associated with government action to mitigate climate change? The government has tabled the idea of introducing a carbon tax which effectively makes the cost of producting goods and services using fossil fuels more expensive. Treasury recently modeled the impact of a $30 carbon tax per tonne. For further information about the estimated impact look at the following:

[|Carbon tax to cost households $16.60 a week] =What are the benefits of cutting our greenhouse gas emissions?= Economists try to compare the benefits and the costs of government policies in order to make sensible recommendations to policy-makers. So a key question to ask is what will happen to global greenhouse gas emissions (and global temperatures) if Australia introduces a carbon tax or other policy to reduce our emissions.

The diagram below (source:[]) shows what has and is likely to happen to global emissions assuming:


 * 1) Australia (and the other countries who have signed the Kyoto Protocol - like most European countries) cuts their emissions by 60% of 2000 levels by 2050. This means that if we emitted 100 tonnes of greenhouse gases in 2000 and 110 tonnes now in 2011 due to our economic growth since 2000, we would have to get all the way down to 40 tonnes by 2050, despite our population growing to maybe 35 million by then compared to 22 million now.
 * 2) USA cuts its emissions by 80% of 2000 levels by 2050. This means that if the US emitted 100 tonnes in 2000 and 105 tonnes now, they would have to get down to 20 tonnes by 2050.
 * 3) China's GDP grows by 10% per annum.
 * 4) China cuts its 'emissions intensity' (the amount of emissions per dollar of its GDP) by 4% per annum until 2040 - ie it becomes a lot more energy efficient and moves substantially towards renewable energy. Note - this still means that China's emissions go up by nearly 6% per annum (5.6% per annum to be precise).
 * 5) Other developing countries' (like India, Indonesia, etc) GDP grows by 6% per annum, and so their emissions also go up by 6% per annum.

In 2009, just __before__ the international climate change talks at Copenhagen (in Denmark), which failed to achieve a global agreement on cutting greenhouse gas emissions, physicist Richard Mueller said:

"Imagine a 'dream' agreement emerging from Copenhagen next week: The U.S. agrees to cut greenhouse emissions 80% by 2050, as President Barack Obama has been promising. The other developed countries promise to cut emissions by 60%. China promises to reduce its CO2 intensity by 70% in 2040. Emerging economies promise that in 2040, when their wealth per capita has grown to half that of the U.S., they will cut emissions by 80% over the following 40 years. And all parties make good on their pledges.

Environmental success, right? Wrong. Even if the goals are all met, emissions will continue rising to nearly four times the current level. Total atmospheric CO2 will rise to near 700 parts per milion by 2080 (the current level is 385), and—if the U.N. Intergovernmental Panel on Climate Change (IPCC) models are right—global temperature will rise about six degrees Fahrenheit at mid latitudes. The reason is that most future carbon emissions will not come from the currently industrialized world, but from the emerging economies, especially China. And China, which currently emits 30% more CO2 per year than the U.S., has not promised to cut actual emissions. It and other developing nations have promised only to cut their carbon "intensity," a technical term meaning emissions per unit of GDP...

If the issue is rising emissions in the next several decades, the bottom line is simple: The developed world is rapidly becoming irrelevant."

See: []

Because of this, some respected economists have expressed doubts about whether it is worthwhile for Australia to take action:

JEFF BENNETT: "The point here is that we should be very, very aware of conducting an economic analysis that weighs up the costs of proposed actions, against the benefits. Now the benefits of action are not necessarily the avoided costs of global warming. You see, the policies that we put in place will not avoid global climate change. There may be some impact but my point here is that even the world's best climate scientists will agree that the sort of impact we will make by imposing these taxes or the cap and trades schemes is minimal... Well my serious concern is that even if the whole world agreed to conform with the sort of international protocols that are being negotiated at Kyoto, then at Cancun and Copenhagen, all of those levels, even if there was complete consensus across the world would result in very, very little by way of climate change impacts."

See: []