Was this year the hottest July?

“Was this year the hottest July (world average) in our recorded history? Somebody showed me some results that said otherwise. I didn't get to check the sources because I was out and it was on his phone. What do the stats and experts say regarding it and where are these false stats coming from?”

ANSWER:

According to reports from NOAA (http://www.ncdc.noaa.gov/sotc/global/201507) , NASA (http://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts+dSST.txt) and JAPAN METEROLOGICAL AGENCY(http://ds.data.jma.go.jp/tcc/tcc/products/gwp/temp/jul_wld.html), this past July (2015) was the hottest recorded.

Some climate change deniers like Joanne Nova (Codling) and Roy Spencer are making claims to the contrary. They are correct in stating that some of the headlines get it wrong, such as those claiming “hottest in 4000 years” because we haven't been recording temperature for that long. The two naysayers though seem to rely on data strictly from UAH satellite data. The problem with this is that satellites do not measure temperature directly, but are inferred from radiance. The UAH data has had problems with the inferred temperatures not matching the actual site surface temperature (http://www.nature.com/nature/journal/v394/n6694/full/394661a0.html). Thus their claims are suspect and need to be investigated further. Even if it wasn't the hottest July on record, it would not indicate a lack of climate change. Variations go up and down in the short term and that is expected. It's the long term trend that is most important and that clearly shows a warming trend.

It is interesting to note that Joanne Nova has a degree in microbiology and molecular biology and not climatology. Roy Spencer is a meteorologist and not a climatologist. The major difference between the two is time frames. Meteorologists produce forecasts in a window no larger than 10 days and usually localized (weather). Climatologists are concerned with long term climate conditions. When considering sources, one would want it from the highest quality and someone actually in the field of studying climate. 97% of publishing climate scientists agree that humans are causing global warming.

To learn more, I suggest taking this free, self-paced course: https://www.edx.org/course/making-sense-climate-science-denial-uqx-denial101x-0

I hope this answers your question.