The changes in global climate pattern have an identifiable common explanation. Extreme weather events derive from unusually large movements of heat and water vapour, both of which are associated with increasing global average temperatures.
Since the early 1990s, world temperature records have shown a strong rising trend. By the end of that decade the trend was statistically significant, which just means that the pattern is noticeably different from before. You’ve probably seen the graph, it looks like a bumpy J. The data behind it are real, you can check the sources.
While natural change has always occurred, the pace of the recent temperature change is unprecedented. Temperatures have continued to rise in the last decade to now, in which time the two first great disasters of present climate change, the near-destruction of New Orleans and low-lying Pakistan, have happened. The assertion that you sometimes hear, that temperatures have not risen since 2000, is false. Again, you can check the data.
We know, effectively for certain, that rising CO2 levels are
responsible for the rising temperatures. CO2 and other greenhouse gases trap heat, so temperatures go up. CO2 traps a large amount of heat, out of all proportion to its small fraction of atmospheric gases. We’ve known this for over a hundred years.
CO2 is a good thing in that it gives us a warm planet to live on, but the more CO2, the more heat is trapped. The temperature changes we’ve seen are consistent with CO2 levels, which are without doubt also rising. The observed climate changes agree with the observed increase in atmospheric heat as measured by temperature, so there is a consistent and highly plausible explanation.
So we have a theory. So what?
Michael Evans,
Armidale