In April of this year, the Mauna Loa Observatory in Hawaii recorded an average concentration of atmospheric carbon dioxide above 410 parts per million (ppm). This was the highest monthly average in recorded history, and in fact according to ice core records it is the highest value in at least 800,000 years.
To be clear, I accept the scientific consensus on the impact of a rising atmospheric carbon dioxide concentration. It is a known greenhouse gas, and the mechanism by which greenhouse gases increase the earth’s temperature is known. While there are uncertainties in the models — and these uncertainties are often used to dispute the underlying science — a constant buildup of greenhouse gases will raise the earth’s temperature.
Part of what is unknown about the effect of greenhouse gases on climate is the impact of feedback loops. These can be both positive and negative.
A warming earth can release methane from permafrost. Methane is a powerful greenhouse gas, and that creates a positive feedback loop.
There are also moderating influences like the oceans, which can absorb a certain amount of carbon dioxide. This means that the temperature increase could be less than what might be expected based simply on the amount of carbon dioxide that was released.
The impact of these feedback loops and moderating influences is one reason climate models can be inaccurate.
But even those who don’t accept the science behind climate change should be concerned about this rise, because it continues unabated. At what point might it become a concern? 500 ppm? 1,000? If you look at the rate of steady increases, this curve should concern everyone on the planet because the increase is slowly accelerating over time:
…click on the above link to read the rest of the article…