CO2 as a benchmark for changes in climate!

"We are experiencing the greatest wave of extinctions since the disappearance of the dinosaurs. Extinction rates are rising by a factor of up to 1,000 above natural rates. Every hour, three species disappear. Every day, up to 150 species are lost. Every year, between 18,000 and 55,000 species become extinct. The cause: human activities." (Ahmed Djoghlaf, head of the U.N. Convention on Biological Diversity)

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I read somewhere that weather is the day to day reality of climate. While you can observe one the other stays well hidden. So, when a climatologist is asked pointedly if global warming is a fact, they cannot answer the question. But, if you were the rephrase it and ask, ‘are climatic trends loading the odds in favor of a warmer climate?’ You would more than likely get a positive answer.

Since I am not a scientist and therefore lack any credibility, I’ll answer the first question more matter of factly. ‘You bet you fanny it’s getting warmer and the worst is yet to come.’

I can say that not only because I’m not a scientist but also because you don’t have to be one to figure out that the species known as man is spewing carbon into the atmosphere as fast as he can go. There's an estimated 7 billion of us cooking and heating with gas, oil or coal or just finding whatever it is we can burn. As the earth warms from this activity, the weather tends to become a little more severe and even occasionally flaky. What's this mean for the future of the planet?

Looking at an ice core graph taken from Vostok, Antarctica, you can tell by the blue line that the amount of CO2 in the air in parts per million has never reached much above 300 ppm (red line) in over four hundred million years! It’s also pretty easy to see that every time those readings went up to that level, the earth was quickly plunged into another ice age. Looks like a pretty regular pattern doesn’t it? First the CO2 rises as does the global temperatures and then, in a relatively short time, down everything goes into the ice freezer. Now, while there are all sorts of theories as to the actual mechanisms at work here, everyone agrees that the CO2 levels along with other indicators like methane are good benchmarks to use. Anyone want to guess where the CO2 level is at today (see small graph)? Here’s a hint:

One other point. With a world population that is expected to rise to 9 billion by 2050, it's hard to see how we are going to curb carbon emissions to any significant degree. And, even if we could manage that miracle, many resources like food and fresh water will certainly become more scarce. Famine, disease and war could well become the norm. Not a very pretty picture for the future of this planet and it's inhabitants. While I think most adults now living will escape the direst of these futures, certainly our children and their children may face a perilous existence that would be brutal and short.

What's the answer to all my doom and gloom? Immediate and severe population control! We need the human population of earth to be cut in half, at the very least, over the next one hundred years. This can be done by the hand of man or by nature or of God. If man is going to do it, he'd better get on his high horse because time is flying by. My personal bet is on Nature and God.

Will the next Ice Age arrive a bit early?

According to the best evidence available coming in the form of ice cores and sea sediments, climate change over the last half million years or so has been a very slow, but steady process.

Ice cores, in particular, have proven to be a gold mine of information for scientists ever since the first one was drilled in 1956 in Greenland. Because the ice has trapped isotopes, air and dust as it formed over the hundreds of thousands of year in areas like Greenland and Antarctica, it has left a concise record that scientists have been able to read almost like a book. In particular, they have constructed a record of CO2 and temperature levels like the one here:

This ice core taken from Vostok, Antarctica shows clearly that much of earth’s history has been spent in icy conditions; what are known as 'glacial periods' that occur about every 150 thousand years (symbol A). The warm periods between these ‘ice ages’ are known as 'interglacial periods' and we happen to be in one of those right now.

The question that interests climate scientists is understanding what factors come into play that trigger the beginning of each period of glaciation. A period of time when both CO2 and temperature levels drop over much of the planet. They want to understand this because its possible that the triggering mechanism might be due, in part, to the effects of elevated CO2. It is troubling to some that while it normally took the earth a period of ten thousand year to build up the CO2 levels by 100 ppm in the past before mankind, it has only taken 52 years to get there with man (see symbol B for level at 2002). In 2011 they have now hit 390 parts per million. The highest ever recorded in over 400,000 years!

One popular theory cites the fact that high levels of this gas in our atmosphere will help to heat up the earths atmosphere (the so-called greenhouse effect). Just look back to our past summer for an example of how hot it felt. This heating causes the poles to melt which, in fact, they are doing as we speak (see Arctic Ice Hits Near-Record Low)! All that fresh water melt off is being dumped into the North Sea and could disrupt the Thermohaline circulation that helps to keep geographic areas of the planet like Europe warmer than they would be otherwise. Once the flow stops, the theory goes, a cycle of ever colder winters will set in that eventually could trigger another ice age. A cycle is set up with more and more continental snow cover that alters the albedo or refractive index allowing more and more solar energy to be reflected back into space. This scenario fits in well with the graph of the ice cores as you can clearly see how both CO2 and temperature profiles rapidly increase before suddenly dropping.

The big question that now arises is will the glacial onset, should it occur, happen slowly (over thousands of years) or might it perhaps be accelerated by the anthropogenic effect of mankind. Only time will tell.

Note: This post did not touch on methane levels, which have also risen to an all time high and which may pose an even greater risk than CO2 in the ability to trap heat. Please see 'The Methane Time Bomb.