Trending Trends Continued: An Alternative View

No matter how much and how well we explain the methods for calculating the length of The Pause, Global Warming Enthusiasts will accuse us of cherry picking the start date.

In this post I will replicate the IPCC’s predicted estimates for temperatures, and show alternative scenarios with a range of trends to the end of 2035, through using an alternative  view which will be sure to please our friends on the other side of the fence- but will demonstrate the limited extent of the joy they should feel at the expected demise of The Pause. As well,  I will also demonstrate what temperatures will need to do before we skeptics can claim victory (our opponents will never admit defeat- that would be heresy).

In these figures I plot running trends of 12 month means of Temperatures of the Lower Troposphere (TLT) anomalies from UAH (Version 6 Beta 5), but starting from the beginning of the record (12 month means from November 1979).  Running trends will be used in this post to demonstrate the effects of changing data values over time.

Fig. 1: Running trends for global TLT to the present

Fig. 2: Running trends for global TLT to the present, closer view.

Note to GWEs: there is no cherry picking: the start is from the start of the record. Each new month’s data point will either increase or decrease the long term trend, but with decreasing effect as the record grows in length. Peaks correspond to warming events, troughs to cooling events. Note also that the recent long term trend is near the lowest it has been since 1998. With the expected increase in temperatures following the El Nino, I anticipate the long term trend to the end of 2016 will be about +1.2C per 100 years.

What of the future? Now according to the IPCC Assessment Report 5, warming for the next 20 years is locked in, no matter what emissions scenario.

“The global mean surface temperature change for the period 2016–2035 relative to 1986–2005 is similar for the four RCPs and will likely be in the range 0.3°C to 0.7°C (medium confidence). This assumes that there will be no major volcanic eruptions or changes in some natural sources (e.g., CH4 and N2O), or unexpected changes in total solar irradiance.”

( https://www.ipcc.ch/pdf/assessment-report/ar5/syr/AR5_SYR_FINAL_SPM.pdf p8)

If I am still around in 2035, this prediction will not be a huge priority for me. However, to illustrate various possibilities, I shall calculate possible TLTs for the next 20 years. (Yes, I know the IPCC is talking about surface temperatures. However if tropospheric temperature change doesn’t reflect surface temperature change for another 20 years there are going to be some serious arguments in climate science circles!)

First, let’s replicate the IPCC predictions for 2016-2035- and in so doing, show The Pause in all its glory. The next figures plot running 12 month mean Temperatures of the Lower Troposphere (TLT) anomalies in degrees Celsius versus global atmospheric carbon dioxide concentration in parts per million (ppm), data from NOAA.  The global record commences in 1980.

Fig. 3: Running trend of Degrees C per 100 ppm CO2

Note again the peaks and troughs, and that the current trend is the lowest it has been since 1996.  The long term trend to December 2015 is +0.65C/ 100 ppm CO2. This is confirmed in the following plot:

Fig. 4: TLT anomalies vs CO2

Now let’s break the record in two: the first half of the CO2 rise and the second half.

Fig. 5:  TLT vs CO2: 1st 30.32ppm

Fig. 6:  TLT vs CO2: last 30.32ppm

There you have The Pause: entirely un-cherry picked, as we are using exactly equal portions of the record: the first and last 30.32 ppm of the CO2 growth from 1980 to 2015.

The next graphs plot CO2 increase over time, from 2001 to 2015.

Fig. 7: CO2 growth (12 month running mean)

Using this trend equation it is possible to estimate CO2 for the next 20 years, and from that, using (A) the trend of the first half of TLT vs CO2, i.e. rapid warming; (B) that of the whole 1980-2015 period, i.e. continuing the present long term trend; and (C) that of the second half of the CO2 growth, i.e. The Pause, calculate three theoretical estimates for the TLT in the best way- from observations. Here are series A and B.

Fig. 8:  Theoretical trends calculated from observations

Note that series A approximately tracks the observed TLTs until about 2002, when the disparity begins. This shows clearly why The Pause is so inconvenient, and why so much effort has been made to eradicate it.

Amazingly, the 2016-35 high mean of 0.7 above 1986-2005, and the low mean of +0.3, as predicted by the IPCC, have been replicated almost exactly by series A and B. (The UAH 1986-2005 mean is +0.02C).  It appears that the temperature trend for the rapidly warming phase up to 2001 exactly matches the trend needed to create the upper limit of their prediction for 2016-35, and the trend overall to 2015 is very close to that of the lower limit. The IPCC is banking on the warming trend from now to 2035 being at least as much as the 1980-2015 trend, and as much as that of the rapid warming to about 2001. Any continuation of a slowdown makes that much harder.

Obviously these series are imaginary, showing the theoretical TLT calculated from CO2 concentration, and without any of the bumps and dips caused by natural variation- volcanoes, ENSO events, and the like. However, they can be used to simulate what temperatures might do over the next 20 years.

I illustrate this with these scenarios, and a fourth, below.

Scenario A allows the 2016-2035 mean to be 0.7C above the 1986-2005 mean and necessitates temperatures sharply rising then continuing at the rate of the higher of the theoretical series (A). Scenario B very slightly exceeds the lower IPCC expectation of +0.3C, and represents a continuation of the current trend. Scenario C is calculated by multiplying expected CO2 concentration by the TLT per CO2 trend for the second half of CO2 growth, indexed to the 1996-2015 mean. As expected it is virtually flat with the 2016-35 mean at +0.14C. This represents an extension of The Pause by another 20 years. Scenario D shows a sharp drop to a 20 year plateau (shown as flat as we have no idea how temperatures may fluctuate) at -0.11C, the lowest 12 month mean of the last 20 years, and about the same average as the 1980-95 period. I have smoothed the beginning months of all four scenarios.

I repeat- these scenarios are entirely imaginary and represent approximate calculated values IF TLT responds to CO2 concentration as it has to now, and nothing else.

Fig. 9: Four scenarios to 2035

I have marked in the trend line for UAH to now.  Scenario A shows what would happen if The Pause came to an abrupt end, with temperatures rising to a record high for 2016, and then keeping on rising at the theoretical rate as if The Pause had never happened. I’m sure there are some Global Warming Enthusiasts who expect temperatures will do just that.

But the IPCC has an out clause- Scenario B. If the current long term trend continues, TLTs will reach IPCC expectations. Which is why GWEs are desperate for The Pause to end and warming to resume at (at least) the slow if not steady +1.1 to 1.2C per 100 years. If it doesn’t they’re in trouble.

Temperatures will need to trend below this to falsify the predictions- and not even as much as Scenario C, which represents an extension of The Pause. Scenario D represents a significant decrease.

The next plot compares the trends under these four scenarios.

Fig. 10: Trends in degrees Celsius per 100 years to 2035 under four TLT scenarios.

Ignore the artificial shape of the curves. At December 2035 the trend for each scenario will be about:
Scenario A: 2.1C/ 100 years
Scenario B: 1.2C
Scenario C: 0.6C
Scenario D: 0.0C

The IPCC expects trends to be between those of Scenarios A and B. A small step up (to a new 20 year mean of say +0.25C) and a new pause- which is entirely possible- would probably still be claimed to be “the hottest decade ever” and “consistent with global warming projections”. We need to emphasise that a pause doesn’t have to be completely flat. A 30 year period with a trend of +0.3C per 100 years should be enough to bring the global warming models into question. However, there will need to be a significant drop in temperatures, or a much longer plateau, for us to claim victory. A 57 year pause would be most embarrassing- but then they would probably blame it on volcanoes!

Finally, even if this El Nino is followed by a strong La Nina, as suggested by NOAA,  it is unlikely The Pause will return until the beginning of 2018, perhaps a little earlier. However, that is not important. The important thing is what happens next. Watch the next two or three ENSO cycles- especially the La Nina dips.

Global Warming Enthusiasts are desperate for rapid warming to resume at least as much as Scenario B. The long term trend must rise above the current rate if they are to feel vindicated. But then, who knows what the actual temperatures will do.

Time will tell.

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The Pause Update: January 2016

UAH v6.0 data for January were released this week.  The dataset has moved to Beta 5, which has caused some interesting changes.  Remember, Version 6.0 is a work in progress, with slight tinkering, until the final version is released.

Here are updated graphs for various regions showing the furthest back one can go to show a zero or negative trend (less than +0.1C/ 100 years) in lower tropospheric temperatures.   In some regions the pause has lengthened, in others it has shortened.  Note: The satellite record commences in December 1978- now 37 years and 2 months long- 446 months.  12 month running means commence in November 1979.

[CLICK ON IMAGES TO ENLARGE]

Globe:

There has been zero trend for 18 years and 11 months.

Northern Hemisphere:

The Pause is back!

Southern Hemisphere:

The Pause has lengthened again.  For well over half the record the Southern Hemisphere has zero trend.

Tropics:

Tropical Oceans:

22 years 5 months.

Northern Extra-Tropics (20-60N- where most people live):

Southern Hemisphere Extra-Tropics (mostly water):

North Polar:

The Pause is 13 years 11 months long- 13 months short of 15 years.

South Polar:

For the whole of the satellite record, the South Polar region has been cooling.  So much for a fingerprint of warming due to the enhanced greenhouse effect being greater warming at the Poles!

Australia:

20 years 10 months.

USA 49 states:

The Pause lives!

 

The Disconnect Between Theory and Reality- Part 2: Winters vs Summers

UPDATE:  PLEASE NOTE UAH DATA FOR THIS POST ARE FROM 6.0 BETA 4.  BETA 5 WILL GIVE DIFFERENT RESULTS.

It was two years ago in 2013 that I last posted on the difference between climate scientists’ expectations and reality, so in this series of posts I bring these points up to date, and add a couple of related points.

What the climate scientists tell us:

Dr Karl Braganza in The Conversation on 14/06/2011 lists the “fingerprints” of climate change (my bold).

These fingerprints show the entire climate system has changed in ways that are consistent with increasing greenhouse gases and an enhanced greenhouse effect. They also show that recent, long term changes are inconsistent with a range of natural causes…..
…Patterns of temperature change that are uniquely associated with the enhanced greenhouse effect, and which have been observed in the real world include:
• greater warming in polar regions than tropical regions
• greater warming over the continents than the oceans
• greater warming of night time temperatures than daytime temperatures
• greater warming in winter compared with summer
• a pattern of cooling in the high atmosphere (stratosphere) with simultaneous warming in the lower atmosphere (tropopause).

And later

Similarly, greater global warming at night and during winter is more typical of increased greenhouse gases, rather than an increase in solar radiation.

In this post I look at whether there is a pattern of greater warming in winter than summer.

This indicator appears to be FALSIFIED for both Northern and Southern Hemispheres:

Fig. 1:  Winter vs Summer, Northern Hemisphere (UAH)

Fig. 2:  Winter vs Summer, Southern Hemisphere (UAH)

And at the Poles:

Fig. 3: Winter vs Summer, Northern Polar region (UAH)

Summers warming faster than winters.  And in Antarctica:

Fig. 4: Winter vs Summer, Southern Polar region (UAH)

Winters (which are mostly night) are cooling much faster than summers.

In Australia overall however, winters are warming faster than summers.

Fig. 5: Winter vs Summer, Australia (UAH 1979-2015):

And Acorn surface data since 1979:

Fig. 6: Winter vs Summer, Australia (Acorn 1979-2015):

And since 1911:

Fig. 7: Winter vs Summer, Australia (Acorn 1911-2015):

However, the patterns are very different in different Australian regions.  North Australia has winters warming faster than summers:

Fig. 8: Winter vs Summer, Northern Australia (Acorn 1911-2015):

While Southern Australia has exactly the reverse:

Fig. 9: Winter vs Summer, Southern Australia (Acorn 1911-2015):

Let’s look at different parts of the South, first the South East:

Fig. 10: Winter vs Summer, South Eastern Australia (Acorn 1911-2015):

And the South West:

Fig. 11: Winter vs Summer, South Western Australia (Acorn 1911-2015):

This shows a particularly strong summer warming effect.

In the North, the pattern seems driven by greater summer rainfall and drier winters:

Fig. 12:  Summer and Winter rainfall anomalies, Northern Australia

There has been much less winter rain in the Southwest (in the Southeast, there has not been as much variation):

Fig. 13:  Summer and Winter rainfall anomalies, South Western Australia

In both the North and Southwest, there are distinct changes in rainfall in the late 1960s or early 1970s:

Fig. 14:  Northern Summer rainfall changes

Note the long term slow decrease to 1973, the wet 1970s and dry 1980s, and all except 6 wetter than average seasons since 1991.

By contrast, the South Western rainy season shows a long term slow increase with great variability until the 1960s, with a sharp step down in 1969, and another in 2001, with less year to year variability.

Fig. 15:  South Western Winter rainfall changes

This shows up in trend maps of summer and winter rainfall 1970-2014:

Fig. 16:  Trends in summer rainfall

Fig. 17:  Trends in winter rainfall

The effect of less winter rain on temperatures in the following summer in South Western Australia is clearly seen in this scatterplot:

Fig. 18:  Summer means and previous winter rain:

While the IPCC and its acolytes in the Climate Council predict less rainfall for southeastern and southwestern Australia, this would not be difficult given the trend for southwestern Australia had been established for 20 years before the IPCC was even formed, and 45 years before AR5. Northern Australian rainfall is not mentioned.

Assessment of this evidence for the enhanced greenhouse effect: FAIL.  Tropospheric data show this to be falsified in both Hemispheres and both Poles.  Australia appears to go against this pattern, but drastic changes in rainfall patterns in the Northwest and Southwest appear to be involved in the difference between north and south.

Theory has been mugged by reality yet again.

Theory and Reality- Part 1: DTR

It was two years ago in 2013 that I last posted on the difference between climate scientists’ expectations and reality, so in this series of posts I bring these points up to date, and add a couple of related points.

What the climate scientists tell us:

Dr Karl Braganza in The Conversation on 14/06/2011 lists the “fingerprints” of climate change (my bold).

These fingerprints show the entire climate system has changed in ways that are consistent with increasing greenhouse gases and an enhanced greenhouse effect. They also show that recent, long term changes are inconsistent with a range of natural causes…..
…Patterns of temperature change that are uniquely associated with the enhanced greenhouse effect, and which have been observed in the real world include:
• greater warming in polar regions than tropical regions
• greater warming over the continents than the oceans
• greater warming of night time temperatures than daytime temperatures
• greater warming in winter compared with summer
• a pattern of cooling in the high atmosphere (stratosphere) with simultaneous warming in the lower atmosphere (tropopause).

and later

Similarly, greater global warming at night and during winter is more typical of increased greenhouse gases, rather than an increase in solar radiation.

This post will examine “greater global warming at night” and whether it can be attributed to increased greenhouse gases.

If night time temperatures (minima) increase faster than day time temperatures (maxima), then the difference between these, the Diurnal Temperature Range (DTR) will decrease.

I use BEST global land temperature data,

http://berkeleyearth.lbl.gov/auto/Global/Complete_TMAX_complete.txt
http://berkeleyearth.lbl.gov/auto/Global/Complete_TMIN_complete.txt

and annual CO2 concentration data from NOAA.

ftp://aftp.cmdl.noaa.gov/products/trends/co2/co2_annmean_mlo.txt

Fig. 1: Global DTR (derived from BEST Land Tmax and Tmin)

Yes, the long term linear trend shows globally DTR has decreased, at a rate of more than half a degree Celsius per century.

Case closed! That is, if you ignore the sudden turnaround in the early 1980s. Since then DTR has been increasing at +1.1C per 100 years.

The plot showing the relationship with CO2 concentration is even more revealing:

Fig. 2: Global DTR vs CO2 concentration

If we break the series in two at the dogleg, we get the following plots:

Fig. 3: Global DTR vs CO2 concentration to 1982

Fig. 4: Global DTR vs CO2 concentration 1982 to 2015

Calling Global Warming Enthusiasts! I am puzzled:

Is DTR decreasing at 1.14 C/ 100 ppm CO2 or increasing at 0.61 C/ 100 ppm?
Can there be any logical explanation for this distinct turnaround?
Is there a problem with (a) the CO2 concentration data? (b) BEST data? (c) the theory behind decreasing DTR being an indicator of enhanced greenhouse warming? (d) all of these?

I now turn to the Australian context, with Australian surface data.

Fig. 5: Annual DTR Australia (from ACORN)

While averaged across Australia, DTR has decreased since 1910, there has been a marked increase recently. As well, the pattern is different in different regions.

Fig. 6: DTR North Australia

Fig. 7: DTR Southwest Australia

Fig. 8: DTR South Australia

Fig. 9: DTR Victoria

Fig. 10: DTR Tasmania

The effect is strongest in the tropical northwest and northeast, and weakest in the southwest and South Australia, Victoria, and Tasmania.

Moreover, the dominant influence on DTR is rainfall:

Fig. 11: DTR vs Rainfall

Definitely not CO2!

Fig. 12: DTR vs CO2 concentration

Assessment of decreased DTR as evidence for the enhanced greenhouse effect: Fail.

Other factors- especially rainfall- overwhelm the enhanced greenhouse effect.

UPDATE:

Perhaps I should be more blunt:  If Global Warming Enthusiasts stick to decreasing DTR as an indicator of greenhouse warming, then this shows BEST and ACORN surface data are completely unreliable.  If they stick to claiming ACORN and BEST are “world’s best practice” then they must accept that DTR as an indicator of greenhouse warming is a dead duck.