So, September 2015 was keeping up with the Joneses, going into the record books as the warmest September on record. Further, 2015’s January through September was the hottest January through September of any year on record, leading several to predict that 2015 will break 2014’s mark as the warmest year ever recorded.
(To clarify, for anyone not keeping up, “on record” refers to the past 136 years. Clearly, there were no thermometers thousands or millions of years ago. While we can estimate, from various sources, what the climate must have been like at certain times in the distant past, there are not actual thermometer readings from those times. What those past estimates do tell us is that it’s (1) very rare for global temperatures to rise this much in only a hundred years and (2) very common for temperature increases to correlate with increases in greenhouse gases.)
The global temperature average does not indicate a cause of the temperature changes; it is simply record-keeping. What it does do is destroy the regularly spouted myth that “the Earth hasn’t warmed since 1998” or “the planet is actually cooling”, which people continue to post on social media sites, regardless of actual facts. This is why I’ve continued to post updates as each month passes and the numbers are collated.