I presented this as a nice example of a dropping temperature profile. Seems very clear what is happening here, the trend is down. But, no, not to these people. Without a vigorous statistical test there is no way one can conclude this is dropping.Ok...
At the beginning of that thread at that site, when I initially showed my temp profiles, these people had no problem in accepting that winter TMin was increasing. That, they said, was well within AGW theory. So for these people this graph of increasing TMin is quite acceptable:

Definite trend as far as they are concerned. But look closely at the two graphs. They are the same! All I did in the top graph was to plot the lowest TMin and flip the image so the numbers were positive. Thus the top graph, which they assumed was another one of my TMax graphs, was in fact a TMin graph flipped.
So this test has exposed some interesting conflicts for these people.
If they claim that TMax is not dropping but has to be "properly" stat tested, then they also MUST apply this to TMin, which they fully accept that AGW would produce.
This shows so clearly their bias against TMax dropping. They will go to any lengths to discredit it. So a dropping TMax must be a real threat to the theory or they would not be so blatantly contradictory and require a double standard. Increasing TMin is OK, no stat test needed because it fits the theory, but oh no, we must apply rigorous stats to prove TMax is dropping.
So this test puts AGW into a real vice. They have two options:
1) TMax dropping is only due to "statistical noise" but not TMin it's increase is caused by AGW.
2) All both TMax and TMin profiles are the result of random variations of cycles within cycles producing the trends.
If they go with #2 then the temperature changes have nothing to do with CO2 emissions and AGW is dead.
If they go with #1 and ONLY TMax's profile is by random noise, but not TMin, then they have a serious conflict and double standard. I have shown that give them a TMin graph mirrored to LOOK like a TMax drop, they will demand a stats test be done. But not when it really shows that TMin is increasing.
Hence if a stats test proves that TMax is indeed dropping and dropping due to natural variation of cycles within cycles, then so too must TMins' increase be from normal variation of random cycles within random cycles. Hence #1 gets rejected and #2 becomes the only option left. CO2 has no effect on temperatures.
I thank the guys at illconcidered for playing the game and being test subjects.

A nice normal distribution curve. Each individual year will show the same shape. But does the apex change over the years? Is "global warming" shifting the apex?
Not over all, however, the 1930's and 1940's has the highest shift in the apex.
Because there are a different number of over all days in the last years (due to missing records), this was done as a percent of each year's count of records. 5C, 6C and 7C anomalies above the baseline are dropping. Fewer days are in each of those ranges. The drop is steeper with 8C, 10C and 12C above baseline:
15C is a nice example of the 1930's being exceptionally hot with more days in this range than any other time in the past 100 years:
But what about the other end, below the baseline, is that changing with time? Doesn't appear to be, -5C, -10C and -15C deviations are flat trends:
So what is happening is since 1920, at least, there are fewer days in the hotter ranges of the year. Not changes in the mid-range temps. This shows a narrowing of the range of swings in temps. And it is not not just the highest of TMax, but all the range of temps of TMax above the average. Summers are not getting as hot today than they did in the 1930s and 1940's.
This is one of the few stations that shows an increase in TMax since 1990, but still not near the 1930's and 1940's. But notice the ups, then back downs. Is there at pattern to this? Once one year reaches its highest temps, what is the probability the next year will be higher or lower?












The over all trend is down, fewer hot days across all of Canada. The heat waves peaked in the 1940's, dropping until the 1980s, and flat since. 20 years of no change in heatwaves.
The trend is also dropping. Fewer days in Canada are above the top 10% temperature now than in the mid 1940's.
Using just one year, 1974 (it has a large swing in the difference), this is what the summer TMax looks like. Even part of the season shows asymmetry in the difference.

This is the same graph showing the difference in the TMin temp, summer nighttime temps. Notice over time the two locations are showing less of a difference in temps between them.
Of the 570 stations only 4 have a complete 100% dataset from 1900-2009 for all of Canada.
Expanded view of the above plot.



However, looking at this from the percent of days in each month we get this:


