The Version 6.0 global average lower tropospheric temperature (LT) anomaly for September, 2017 was +0.54 deg. C, up from the August, 2017 value of +0.41 deg. C (click for full size version):

Global area-averaged lower tropospheric temperature anomalies (departures from 30-year calendar monthly means, 1981-2010). The 13-month centered average is meant to give an indication of the lower frequency variations in the data; the choice of 13 months is somewhat arbitrary… an odd number of months allows centered plotting on months with no time lag between the two plotted time series. The inclusion of two of the same calendar months on the ends of the 13 month averaging period causes no issues with interpretation because the seasonal temperature cycle has been removed as has the distinction between calendar months.

The global, hemispheric, and tropical LT anomalies from the 30-year (1981-2010) average for the last 21 months are:

YEAR MO GLOBE NHEM. SHEM. TROPICS
2016 01 +0.55 +0.72 +0.38 +0.85
2016 02 +0.85 +1.18 +0.53 +1.00
2016 03 +0.76 +0.98 +0.54 +1.10
2016 04 +0.72 +0.85 +0.58 +0.93
2016 05 +0.53 +0.61 +0.44 +0.70
2016 06 +0.33 +0.48 +0.17 +0.37
2016 07 +0.37 +0.44 +0.30 +0.47
2016 08 +0.43 +0.54 +0.32 +0.49
2016 09 +0.45 +0.51 +0.39 +0.37
2016 10 +0.42 +0.43 +0.42 +0.47
2016 11 +0.46 +0.43 +0.49 +0.38
2016 12 +0.26 +0.26 +0.27 +0.24
2017 01 +0.32 +0.31 +0.34 +0.10
2017 02 +0.38 +0.57 +0.19 +0.07
2017 03 +0.22 +0.36 +0.09 +0.05
2017 04 +0.27 +0.28 +0.26 +0.21
2017 05 +0.44 +0.39 +0.49 +0.41
2017 06 +0.21 +0.33 +0.10 +0.39
2017 07 +0.29 +0.30 +0.27 +0.51
2017 08 +0.41 +0.40 +0.41 +0.46
2017 09 +0.54 +0.51 +0.57 +0.53

The linear temperature trend of the global average lower tropospheric temperature anomalies from January 1979 through September 2017 remains at +0.13 C/decade.

The UAH LT global anomaly image for September, 2017 should be available in the next few days here.

The new Version 6 files should also be updated in the coming days, and are located here:

Lower Troposphere: http://vortex.nsstc.uah.edu/data/msu/v6.0/tlt/uahncdc_lt_6.0.txt
Mid-Troposphere: http://vortex.nsstc.uah.edu/data/msu/v6.0/tmt/uahncdc_mt_6.0.txt
Tropopause: http://vortex.nsstc.uah.edu/data/msu/v6.0/ttp/uahncdc_tp_6.0.txt
Lower Stratosphere: http://vortex.nsstc.uah.edu/data/msu/v6.0/tls/uahncdc_ls_6.0.txt

A diversion from global warming topics.

The simple little probability problem below has apparently been debated for many years. It came to prominence when Marilyn vos Savant answered a reader’s question about it. Her answer was believed to be wrong by some of the greatest statistical minds in the world, and eventually most of them admitted she was correct after all.

A story about that debate is here.

But I maintain that the answer depends upon an unstated assumption, and so there is no correct answer. Of course, I could be wrong. Disagreeing with a person having the highest IQ in the world is, statistically speaking, not a smart thing to do.

The Monty Hall Problem

There are three doors, and behind one of them is a new car, and behind the other two doors are goats. You want the new car. You choose door #1, knowing you have a 1 in 3 chance of winning.

Monty Hall then opens door #3 and shows you a goat there. Should you change your pick from door #1 to door #2? Most people said no, that you still don’t know whether the car is behind the first or second door, and all that has happened is your chance of winning has simply improved from 1/3 to 1/2.

But Marilyn vos Savant said “yes”, that you should switch. Experts disagreed.

From what I can tell, through, it entirely depends upon why Monty Hall showed you what was behind door #3.

If there is a goat behind door #3, then clearly the new car is behind either door #1 or door #2. If Monty Hall was going to show you door #3 no matter what was behind it, then your chances are still 50/50… you might as well stay with door #1.

BUT…if Monty Hall was only going to show you a remaining door that had a goat behind it, then you should switch to door #2. The reason is you would have new information you didn’t have before…that if he knew that the new car was behind one of the remaining doors, he was going to in effect tell you that by not opening that door.

In that case, you actually have a 2 in 3 chance of winning by switching doors.

But, as far as I can tell, which of these two assumptions is in effect was never stated, and so there is no correct answer to the problem.

(RIP, Monty Hall).