Kim O'Hara wrote:Alex,
My last post was another attempt to get you to see for yourself that the data you keep pushing at us is misleading because it is irrelevant. If I want to go from my house to the nearest coffee shop, a map of the whole world is useless. If we want to understand what is happening to the climate we depend on, your 600 million year graph is useless. What matters to us is not the differences and similarities over 600 000 000 years. Not even the differences over 600 000 years. The climate for most of earth's history did not and could not support human life. The climate for all except the last 1000 years did not accommodate coastal cities. The climate for all except the last 100 years did not form the essential preconditions for global agriculture supporting several billion people.
If we want to know whether the climate in the next hundred years can continue to support our civilisation, we need to know how it is changing from what actually does support our civilisation.
We are talking about climate change
and relevance of human activity on climate
change. In reference to that I've posted all the graphs and quotes.
I am not talking about climate
at which current humans can live. We are not talking about real (or imagined) scenarios of what would occur if CO2 levels increased to more usual levels. What our main point is whether climate
change is caused by humans or not.
Because we are talking about climate
change, it makes sense to gather AS MUCH DATA as possible and based on that, make conclusions. Since the Earth existed for 4.5 billions of years and was changing quite a lot (without humans, btw) we need to take THAT in consideration - 100 years, even 100,000 years is too little (<1%). If one want to learn well about a certain subject, one studies it as much as possible.
Our subject here is climate
change and human's role in it.
Also to call current climate
extreme, we need reference point from which to measure. Past 100 years do not count when considering that this earth existed for 4.5 Billion of years.
As I have repeatedly shown, the temperatures and CO2 levels were changing. For this discussion it doesn't matter if humans could live in those circumstances, as it is a different topic. The topic is climate
change and human influence on it. So I wonder, how could humans influence the climate
levels of CO2 which were 500 millions of years ago? If nature could raise CO2 levels as high as 7,000 ppm, then I am sure it could be explained for very tiny levels of 390ppm today. If raise of CO2 levels cannot be explained without human's CO2 emission, then explain all those very high levels of CO2 which stayed for millions of years? It is irrelevant to this discussion whether humans can live in higher CO2 levels. What is relevant is the natural change of the climate
.The main argument about CO2 causing temperature to rise is incorrect:..CO2 lags an average of about 800 years behind the temperature changes-- confirming that CO2 is not the cause of the temperature increases. One thing is certain-- earth's climate has been warming and cooling on it's own for at least the last 400,000 years, as the data below show. At year 18,000 and counting in our current interglacial vacation from the Ice Age, we may be due-- some say overdue-- for return to another icehouse climate!http://www.geocraft.com/WVFossils/last_400k_yrs.html"Even if CO2 levels were many times higher, radiative heating physics shows that it would make virtually no difference to temperature because it has a very limited heating ability. With CO2, the more there is, the less it heats because it quickly becomes saturated. For a detailed explanation go to:http://www.geocraft.com/WVFossils/greenhouse_data.html
Kim O'Hara wrote:That blue line heading straight up at the extreme right of the graph is the key to the whole problem - and you can barely see it, let alone see its relationship to the red line, which is the other half of the problem.
That is because what has happened in the past 100 years is NOTHING compared to what was before. Our 350-390ppm CO2 levels are insignificant compared to
up to 7,000ppm CO2 levels of Cambrian period. Current rise from 350-390ppm is nothing compared to rise of CO2 from 4,500ppm to ~7,000ppm in Cambrian. Our temperatures are also very LOW compared to where it has been for millions of years. Whether humans can survive is irrelevant to the discussion. What is relevant is the fact that earth was undergoing significant climate
change for millions and billions of years.
When you acknowledge what I'm saying, we can take the next step.