The news has been everywhere, that July of 2015 was the hottest month in recorded history. I could link dozens of news articles about it, but instead I will simply link the source page. Here is the quote from the NOAA on the new all-time record high temperature for the planet Earth.
“The combined average temperature over global land and ocean surfaces for July 2015 was the highest for July in the 136-year period of record, at 0.81°C (1.46°F) above the 20th century average of 15.8°C (60.4°F), surpassing the previous record set in 1998 by 0.08°C (0.14°F).”
So technically, they are saying that July of 2015 measured 16.61°C, using that 0.81°C anomaly. Now, first things first. July is typically the warmest month of the year, which I have covered in depth, both in my book and in articles on this website. So yes, if 2015 was the warmest July on record, then it would in fact be the warmest month ever recorded. The real question is, was it the warmest July on record?
While the satellite data only goes back to 1979, that is a reasonable place to start with the comparison. So using the data from the UAH and RSS satellite data, I got the following anomalies for July.
A little bit of disagreement between the two of them, but 2015 comes in as 7th and 8th place, for years since 1979. That is a far cry from the hottest year in recorded history. So both sets of satellite data say that the NOAA is wrong.
My preference for monitoring global temperature is the NCEP CFSR though. There is one key scientific reason that I prefer it, but I also simply like that it gives actual temperatures, instead of just anomalies. Here is what the NCEP data shows.
Now 2015 has dropped all the way down to 10th place, with a temperature of 16.49°C, running 0.18°C behind the record year of 2002. Now for my favorite comparison, the global anomaly maps from the NOAA and the NCEP, via Weatherbell.
In addition, the NCEP data shows that August, which is on average 0.11°C cooler than July, of 2003 and 2006 were warmer than July of 2015, at 16.56°C and 16.50°C respectively. This demotes the most recent month all the way down to the 13th warmest month, since 1979.
So while I wouldn’t say that the NOAA just told the biggest lie, I will say that this is the hottest lie of the century, but sadly, that is one record that will soon be broken.