The past two weeks have brought new signs that global warming is not only continuing, but may in some respects be accelerating. Three independent agencies in the United States and Japan made the announcement that 2014 was most likely the warmest year on record since at least 1880, and very likely for several millennia before that.
The only major land mass that featured relatively cool temperatures for the year — but still warmer than average — was parts of the U.S. and Canada.
There was also word that the concentration of carbon dioxide in the atmosphere has already been nudging above 400 parts per million, a symbolic milestone first reached for an extended period in 2013. This is the highest level of this global warming pollutant in all of human history.
We also found out that ocean temperatures reached record levels in 2014, with portions of every major ocean basin attaining new highs. But there is more to the ocean temperature measurements than first meets the eye, since we tend to focus more on sea surface temperatures.