“Reading, we have a problem.”
As a followup to my post about whether July 2019 was the warmest July on record (globally-averaged), I’ve been comparing reanalysis datasets since 1979.
It appears that the ERA5 reanalysis upon which WMO record-temperature pronouncements are made might have a problem, with spurious warmth in recent years.
Here’s a comparison of the global average surface air temperature variations from three reanalysis datasets: ERA5 (ECMWF), CFSv2 (NOAA/NCEP), and MERRA (NASA/GSFC).
Note that only CFSv2 covers the full period, January 1979 to July 2019:
ERA5 has a substantially warmer trend than the other two.
By differencing ERA5 with the other datasets we can see that there are some systematic changes that occur in ERA5, especially around 2009-2010, as well as after 1998:
These kinds of changes suggest to me that differences in how the satellite deep-layer air temperatures from MSU and AMSU are handled, which through the data assimilation process can affect surface temperatures.
Reanalysis datasets’ dependence upon various data sources is difficult to diagnose because a wide variety of data are included in them: surface thermometers, weather balloons, aircraft, ships, buoys, and a variety of satellites.
Because the satellites are the only truly global source, they have the potential to significantly impact global-average quantities.
SEE ALSO: Climatologist: July 2019 Was Not The Warmest Month On Record
If the satellites turn out to be the main reason for these differences, this means how the satellites are adjusted as the orbits decay, intercalibrated with each other, and even whether certain problematic satellites are excluded from analysis, all become significant factors in the interpretation of global average temperatures from the reanalyses.
For example, the WMO’s pronouncement that July would be at or near-record warmth (which is based upon the ERA5 reanalysis) would then depend on how they did their satellite data adjustments.
So, I am no longer standing by my previous statement that the current reanalysis datasets should be used for determining record-warm months.
At this point, it’s not even clear to me that reanalysis datasets are better for inferring record high (or low) surface temperatures than our (UAH) satellite dataset is, even though the satellite senses much more of the troposphere than it does of the surface.
This is all very preliminary, and I am open to other interpretations.
Read more at Dr. Roy’s Blog
“It appears that the ERA5 reanalysis upon which WMO record-temperature pronouncements are made might have a problem,”
“This is all very preliminary, and I am open to other interpretations.”
What other interpretations???? How about the WMO is lying… as usual.
HINT = WMO
HINT = In keeping with its mandate to promote the standardization of meteorological observations, the WMO maintains (it’s own) numerous code forms for the (it’s own) representation and exchange of meteorological, oceanographical, and hydrological data.”
HINT = WMO record-temperature pronouncements
HINT = WMO history of lots of “scientific” papers and overwhelming expert analysis but they do not share any actual research data or methods. What we get instead is doctored data and alarmist pronouncements tinged with HINTS of spurious correlations to physical science.
HINT = Iran became a member of the Council after 15 years, beating its rival Saudi Arabia and gaining the majority of votes.”
HINT = UN Agenda
Pretending for a second that humans can control the earths temperature through a reduction in the portion of CO2 generated by humans , who would set the Goldilocks temperature any way ? I suppose that would be the one world government so anxiously sought by commie lovers and eco- anarchists .
Yes lets send $trillions of dollars that we don’t actually have to a new level of government backed by socialists and one world government seekers .
Amazing naivety .
Pretending for a second that humans can control the earths temperature through a reduction in the portion of CO2 generated by humans , who would set the Goldilocks temperature any way ? I suppose that would be the one world government so anxiously sought by commie lovers and eco- anarchists .
Yes lets send $trillions of dollars that we don’t actually have to a new level of government backed by socialists and one world government seekers .
Amazing naivety .
If someone accepts those temperatures as fact, with huge step changes hotter in 2009-2010, and they want to put this all on CO2 concentrations, it just doesn’t add up. CO2 did not make a big jump in concentration in that year. And it has been level or dropping since. Can’t correlate with CO2.
Must be something else.
CO2 doesn’t bake, if it doesn’t correlate.
Yes, they are constantly “adjusting” their numbers to make them fit with their models instead of observable reality. The fact that this hasn’t become a huge scandal is quite telling.
The biggist lies and Fake News thats all we get July 2019 was Not the Hottest the facts that July is in the Summer and Summers are always hot get used to it and the Earth Is Not Fragile and the idea that were destroying the earth The Delicate Balance of Nature is idiotic