In late September the LMCC Council Chamber was full of interested folk gathered to hear four glacial scientists relate the findings of their work. In the audience were young folk, older folk, those that seemed to know a lot and those that were there to learn, a wide spectrum of interested public.
The scientists were there because they were concerned about the lack of real scientific information about climate change that is being shared with the public. They had decided to go on a road trip to share their scientific findings and had some climate conversations on the way.
They introduced the topic of Climate Change as one of perspective, that as a species that only inhabits the earth for 0-80 or so years they pondered that if perhaps we lived to a ripe old age of 5000 as the Bristle Cone Pines do we may see things differently.
They explained that our atmosphere is a function of time, climate is the long term patterns and weather is the daily variability. By looking at ice cores a detailed picture of the atmospheric concentrations of gases in air, particulates and temperature can be determined to give a picture of the climate over time.
Tessa Vance, an ice core climatologist explained climate change has always happened, sometimes fast, sometimes slow but today the changes are being driven by humans.
The ice core measurements of CO2 ,carbon dioxide, up until 1000 years ago were relatively stable at about 280 parts per million, but then from about 1775,when the steam engine came into being CO2 levels started trending up, culminating in the last decade being the hottest on record.
The scientists went on to illustrate several different climatic models that were used to predict CO2 levels to try an explain the match of data they find in the ice cores . There were models that included volcanic activity, solar flares, clouds, terrestrial uptake of CO2 ,atmospheric chemistry, ocean uptake of CO2 , sea ice and water vapour. The only graph that matched the actual CO2 emissions recorded in the ice core sample was the graph for man-made CO2 sources related to the burning of fossil fuels.
The evidence was compelling, they explained how there are different forms (isotopes) of carbon that are 'signatures' for different sources of carbon from volcanoes, plants or fossil fuels, so they are definite about the source. The amount of fossil fuel consumed since the advent of the steam engines matches the volume of CO2 that has been produced and measured, they have measured 3.5 km of ice core, and the atmospheric records match the ice core data.
Currently CO2 levels are at 387ppm way out side the range ever before experienced on earth. The CO2 levels and earth's temperature are heavily correlated, and so we see an overall warming trend of 0.8 oC. Since the 1970s the average warming rate has been 0.17oC /decade, with the past decade the hottest on record.
One of the scientists studied the impacts of CO2 in the oceans, he described it as 'the other CO2 problem' because ¼ CO2 and 90% of earth's heat are in the oceans. Also when CO2 mixes with water it forms an acid and there has already been 20% increase in ocean acidity which is affecting the physiology of chalky skeleton organisms such as corals, whose skeletons aren't forming as well. The prediction was that by 2020-2050 corals will not be able to survive the increased acidity of the ocean.
Another organism that is affected by the changes in the ocean's chemistry is the worlds most abundant animal, the tiny krill. At the base of the food web, without krill, there is no food for larger animals to eat, potentially dire impacts on the world's already fragile fisheries.
The team of scientists had a Q & A session after sharing their detailed knowledge and explained that a 2oC change in temperature would be like moving Lake Macquarie to Rockhampton. Some of the obvious impacts would be coral bleaching and cereal crop productivity decreasing at low latitudes & increasing at high latitudes. Our earth's temperature has almost increased 2oC now.
A temperature of more than 3oC the present would result in an increase frequency of storms and floods, severe water stress, 30% species extinction and 30% of global wetlands would be lost. At 4-5oC we'd get substantial health burdens with infectious and other diseases on the rise.
On the question of skeptics, they stated 1 in 400-500 scientists are climate change skeptics with only a few believing the impacts of climate change will result in 1- 2oC temperature increase, most mainstream scientists believe we're heading for 2-4 oC unless there is concerted action, especially as sea level rise is running at the upper limit of predictions and there is a lack of understanding on the stability of ice sheets.
On the question of tipping points, it was noted that the last time the Greenland Ice sheet melted the sea level rose 6m in a few centuries.
As scary as the information was there was a simple and cost effective way to avoid such extreme futures. As simple as political will to get on with the job of 2% reduction/annum. It is very doable and is economically feasible, it gets more expensive the longer the delay and a major outcome of the Copenhagen talks was that no country is questioning the need to keep temperature rise below 2oC.
At the end of the evening Lake Macquarie City Council was commended for bringing the scientists to the city to share their findings, an ice-core was on hand so we could admire the time encapsulated air bubbles and everyone was certainly the wiser for being there.
We're in the electorate of Charlton and our Federal Member is Greg Combet, recently appointed Minister for Climate Change and Energy Efficiency.
You can be part of the solution by helping Greg do his job. Let him know how you feel about the future we're leaving our children and our grandchildren.
Contact details are
email greg.combet.mp@aph.gov.au
Suite7, Level1,
342 Main Road,
Cardiff, 2285
phone 02 4954 2611
