Friday, June 17, 2016


For the 13th consecutive month, May 2016 was the warmest month on record for global temperature according to the NOAA.  Whether this was the 8th (NASA) or the 13th consecutive month (NOAA) depends on which data set you are looking, but none of the different observation sets indicate significantly different patterns or trends.

It is now expected that a moderating el Nino, which stirs up the earth’s heat energy content to put slightly more heat into the surface areas on which measurement is concentrated, will result in some slowing down. So it is possible that May will be the last “record month” for the time being. What is abundantly apparent from the data of the last two years, however, is that the underlying global temperature trend is continuing to move inexorably upward. Comparison with peak years coinciding with previous el Ninos (eg 1998) shows a clear and substantial increase The “pause”, if it ever existed, is well and truly buried.

One of the hopes, promoted inter alia by climate sceptics trying to play down climate impacts, was that we would see some amelioration of temperature rises with CO2 concentration, due to an established physical phenomenon called the log linear effect, in which, if CO2 were the only factor involved (ie ignoring feedbacks) the warming impact eventually rises much more slowly than the rise in CO2 concentration.[1]  To illustrate, doubling from 560 ppm to 1120 ppm might theoretically only produce the same impact as doubling from 280 ppm (pre-industrial level) to 560 ppm. What now increasingly looks like a steady linear increase suggests that this factor is not yet having much effect.

[1] This issue is one of those discussed on the page SCIENCE VS SCEPTICISM

No comments: