Global Warming and climate change
Leon Ashby looks at some of the data and opinions surrounding this issue, trying to make sense of it
US president George W Bush recently withdrew the US from the Kyoto agreement on protocols for reducing greenhouse gases worldwide. His decision has been widely criticised as the US produces approximately 36% of the world green house gas emissions. Australia produces 1%.
Australian landholders are interested in this issue for a number of reasons
(1) Will the Federal government use the greenhouse gas arguement to impose restrictions on treepulling, animal emissions, and energy consumption?
(2) Will the research be done properly to ensure the facts are correct and fully understood before any regulation begins?
(3) Will there be an opportunity to be paid for carbon storing in trees or other vegetation?
(4) Are the claims by some green groups true or exaggerated?
There have been many comments in the media such as the following (From the BBC 05/08/99) :The US Geological Survey says global sea levels have risen by about 10cm (four inches) in the last century. If all the world's glaciers melted, it says sea levels would rise by 80m (260 feet).
The claims associated with more greenhouse gases are
(a) Global warming
(b) Icecaps melting (see Environmental Myths)
(c) Sea levels rising
(d) more extreme weather (floods, droughts)
(e) Habitat changes, and species extinction
(1) On many web sites, there are graphs showing world wide temperatures over the past 100 years and the amount of carbon dioxide in the atomosphere for the same period. They show the carbon dioxide increase began noticably after 1950.
This Graph shows the assumed carbon dioxide levels in blue using core ice samples (circles, squares, triangles) as a guide
The red line is actual measurements
The Graph below shows global temperature fluctuations over the last 100 years
When you look at the temperature changes for the last 100 years ( graph above) you will notice
(a) constant fluctuations,
(b) most of the temperature rise of 1 degree celsius over the last 100 years occurred from 1920 to 1940.(before the carbon dioxide levels rose substantially.)
(c) The temperature flattened out from 1940 to 1980
(d) The temperature is not going up constantly similar to the carbon dioxide levels. (see top graph)
Without having any bias, it would seem that Global warming could have other factors than a CO2 increase causing it, and that the 1 degree measured so far may only be in the "normal range"
Here`s a few more bits of information to consider.
(2) There is evidence that while parts of the world warm up, others are cooling e.g.
(a) Greenlands southeastern ice field (where 8 planes were left during World War 2 -1942) has thickened - the planes were 268 feet under the surface of the ice when found in1992. See http://www.greeningearthsociety.org/Articles/1999/squadron1.htm
(b) In western Greenland, Krabill et al. (1995) found a net increase of more than six feet in the thickness of the ice from 1980 to 1993. See Krabill, W., et al., 2000, Greenland Ice Sheet: High Elevation Balance and Peripheral Thinning. Science, 289, 428–230.
(3) The rise in the ocean level (predicted to be between 3.5 inches and 37 inches by several scientific organisations) will be due to the expansion of the oceans water, far more than due to any melting icecaps. The icecaps have substantial amounts of ice that float in the water. When this ice melts, it will end up occupying almost the same volume in the ocean as the amount of water it displaced as ice. Therefore it will make next to no difference to the ocean level.
(Only ice which was on land that melts, and increases the ocean volume will have an effect on sea levels.)
(4) The worlds ocean level has supposedly risen between 4 and 8 inches already in the last 20 years according to several scientific groups. But other evidence from Tasmania and Australia`s ports suggest otherwise (see Environmental Myths or the site http://www.greeningearthsociety.org/Articles/2000/sea.htm )
Then there are these points to consider
(5) Even if we stopped increasing greenhouse gases tommorrow, it would take a fair while for the effects of extra greenhouse gases (whatever they are) to stop.
(6) And even if we stopped increasing greenhouse gases tommorrow, we may not stop Global warming to any degree as other factors may increase the temperatures.
(7) Because of the erratic climate variations we have always had, it is almost impossible to be sure about any climate changes that are less than a 10 % variation to the average change over many years (e.g.rainfall, droughts etc) or a 2 degrees Celsius change. (This is the amount a little ice age in the middle ages was apparently believed to be. - See interview with Dr Sallie Baliunas on Global Warming in articles)
(8) According to the CSIRO and other groups, there is a "Missing sink" -- Of the estimated seven billion tons of carbon from human-generated carbon dioxide going into the atmosphere each year, about three billion tons stay there.(this can be calculated from the concentration in the atomosphere) We know the oceans take up about two billion tons. Where is the remainder going?
CSIRO believes the remainder must also be going into the ocean or be taken up by living plants. ( have they thought of the timber thickening and encroachment occurring in northern Australia and other parts of the world - See Carbon Sequestration article by DR Bill Burrows)
Other things to take into account
There may be other things we need to take into account in regards to weighing up our response to global warming. Many cannot be verified. These include
(1)Fluctuations in global temperature over decades being normal, This could be due to any number of things we haven`t thought of.
(2) There may be benefits to Global warming - more rain in some areas, and extra rates of vegetation growth (due to higher levels of CO2 and water.)
(3) There could be more violent storms and floods and more occurance of droughts. This is often stated by those warning about serious consequences of global warming. Should we just factor in an increased risk to these occurances or try to prevent them? Global Warming or not we have to be aware of their potential impact on us anyway.
(4) There could be positive feedback (when global warming causes more global warming) and negative feed back (when global warming causes global cooling)
(5) Could we adapt to any climatic changes for less cost and disadvantage than trying to prevent any climate change?
(6) Our islands and some land masses may be sinking rather than there being rising sea levels. A number of people have brought this point up. One example is Adelaide as John Daly comments -
Adelaide is a prime example of local sea level rise due to urban subsidence
( Belperio, A, "Land Subsidence and Sea-level Rise in the Port Adelaide Estuary: Implications for Monitoring the Greenhouse Effect", Australian Journal of Earth Sciences
, v.40, p.359-368, 1993.)
. Its two stations (listed above) are the only ones where a sea level rise is greater than the IPCC estimate. The NTF survey points out the Adelaide anomaly and directly attributes it to local subsidence, not sea level rise. NTF reaches its conclusion on grounds that the neighboring stations at Port Lincoln, Port Pirie, and Victor Harbour show only a rise of +0.3 mm/yr between them, compared with Adelaides + 2.0 mm/yr
Here are some details on the Kyoto agreement
(From the Greenhouse Office)
The Kyoto Protocol is an international treaty under which developed countries (those listed in Annex B of the Protocol) have agreed to limit net greenhouse gas emissions. Many countries, including Australia have signed the Protocol. To become legally binding the Protocol must be ratified by at least 55 countries, that account for at least 55 per cent of the total 1990 carbon dioxide emissions of developed countries. It is unclear how long this may take.
Australia's target is to limit growth in greenhouse gas emissions to 8 per cent above the 1990 levels (often referred to as the 1990 baseline) by 2008 - 2012. Emissions are effectively averaged over the five years.
Sources that need to be counted in the 1990 baseline year are all emissions from the energy, agricultural, waste, and industrial processes sectors.
Article 3.7 of the Protocol allows countries that had net emissions in 1990 from the land use change and forestry sector, to count these emissions towards their 1990 baseline. Australia's land use change and forestry sector was suppoably a net emitter in 1990 and therefore Australia is eligible to count land use change in its 1990 baseline.
This mechanism was included in the Kyoto Protocol in recognition that land clearing contributes to a substantial proportion of Australia's total emissions. The trigger mechanism will allow Australia to gain credit for the efforts made to reduce emissions from land clearing. Most other developed countries have net sinks from the land use change and forestry sector, not net emissions, so Article 3.7 does not apply to them.
Australia does not account for our timber thickening in it`s sink calculations which is substantial according to Dr Bill Burrows (Qld beef institute) who has been measuring timber growth across Qld for 37 years and his research shows an average of 922kg / ha of biomass is added to 60 million ha of Queenslands grazing woodlands each year..
The United States cannot single-handedly block the Kyoto Protocol, which will enter into force 90 days after it has been ratified by 55 states, but it can come close to doing so.
The ratifying parties must include countries representing at least 55 per cent of the industrialised world's total carbon dioxide emissions, and the United States alone accounts for 36 per cent of that output. Australia accounts for about 1%
Some interesting Quotes
Tom Wigley, one of the International program on climate change's most prolific authors, gave former US vice president Al Gore this news: If all of the nations of the world do what they said they would at Kyoto, the earth's temperature in 2050 will be 0.07°C cooler than it would be if we had done nothing. And by the year 2100? A grand total of 0.14°C. That is one seventh of one degree C
Another point to consider about Kyoto is, besides doing next to nothing, it will cost a fortune. Energy Information Administration, MIT scientists, the Australian Bureau of Resource and Agricultural Economics (ABARE), and one of the most respected econometric modeling firms, WEFA Inc. Within a few iotas, they all say the same thing: Kyoto will cost between 1 percent and 3.5 percent of our Gross Domestic Product (GDP) per year.
Global warming could be very modest. - Scientists from the United Nations Intergovernmental Panel on Climate Change (IPCC) say this. In Chapter 9 of their new report is an illustration of the average warming projected by dozens of various "general circulation" climate models, the most sophisticated type. It turns out to be around 2.5°C over the next 100 years. But it is well known that these same models have, in general, predicted a bit more warming than has actually occurred.
With that in mind, two of IPCC's most respected scientists, Myles Allen and J.F.B. Mitchell, asked the following question: "Given the behavior of the atmosphere and our models, what is the most likely warming for the next 100 years?" Their answer: 1.5°C. They published that result in the October 4, 2000, issue of the prestigious journal Nature.
The community needs to be kept up with as much good research as possible.
The debate should be be kept from polarised positions.
The facts are very uncertain
My view is only if the costs are modest and the gains definite, that any country should sign up with the Kyoto agreement
Leon Ashby, Convenor for Landholders for the environment