Statement on GAT

Vincent J. Curtis

2 Aug 23

UAH is reporting that the global average temperature (GAT) of July, 2023, was 0.26℃ higher than June, 2023.  Meanwhile, the source I’ve been quoting on my Twitter feed (https://temperature.global) provided data showing that July, 2023, was 0.01℃ cooler than June, i.e. from 14.16℃ to 14.15℃.  So, we have a discrepancy both in magnitude and direction between UAH and my source.  What could explain this discrepancy between these two respectable sources?

The answer is that they’re measuring different things and purporting them to be the GAT.  This is not as unreasonable as it sounds, though it does point to weaknesses in climate science.

UAH measures the temperature of the lower troposphere, and reports a GAT monthly. UAH cautions that the results are not precisely comparable to surface temperature records or models.

My source takes unadjusted surface temperature data from the following sources: NOAA Global METARs, NOAA One Minute Observations (OMOs), NBDC Global Buoy Reports, and MADIS Masonet Data.  As the data is received, the program checks the input data for quality, forwards the data into a database for processing, analyzes the data, and puts out a global temperature.  My source processes about 70,000 stations per orbit, and global temperature is continuously updated.  “Every minute the data function module calls the database to create the running 12M global average.”

Hence, what we are seeing in the discrepancy between UAH and my source is the difference between 12M surface data and lower troposphere data.

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