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S.Pansa

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Re: Global Surface Air Temperatures
« Reply #950 on: May 04, 2016, 09:55:46 PM »
http://data.giss.nasa.gov/gistemp/tabledata_v3/NH.Ts.txt

  N.HEMI Temperature Anomalies in 0.01 degrees Celsius      base period: 1951-1980

Year    Jan   Feb  Mar  Apr  May  Jun   Jul   Aug  Sep  Oct  Nov  Dec       
2015   136  134  152  121  119  120  102  112  120  137  158  189 
2016   192  245  236 **** **** **** **** **** **** **** **** **** 

Divide by 100 to get changes in degrees Celsius (deg-C).

The above numbers are for the Northern Hemisphere land surface air temperature.  The Northern Hemisphere land+ocean data for GISS is here:

http://data.giss.nasa.gov/gistemp/tabledata_v3/NH.Ts+dSST.txt


CMIP5 dataset can be downloaded from:

http://climexp.knmi.nl/selectfield_cmip5.cgi

Using RCP8.5, I calculate that the CMIP5 ensemble mean projection for 2016 was  0.95°C (relative to baseline 1951-1980) for global temperature, and 1.15°C for the Northern Hemisphere.   2016 will probably exceed those values, but of course it would be more meaningful to use an ENSO-neutral year (rather than a super El Nino year) to compare models vs. observations.

Are these CMIP5 Temps based on the updated (actual) forcings? For instance those mentioned in this Real Climate post (I guess they are from the Schmidt et.al 214 paper in Nature Geoscience). From the figure shown in this  post by Gavin Schmidt there seems to be a difference of about 0.1 C bewtween the two versions ( in 2013, pure eyeballing ).
If that is the case, would the CMIP5 ensemble mean projection for 2016  be more around 0.85°C with the updated forcings?
Thanks!

Steven

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Re: Global Surface Air Temperatures
« Reply #951 on: May 04, 2016, 11:02:47 PM »
Are these CMIP5 Temps based on the updated (actual) forcings?

The CMIP5 data which I linked to in Reply #953 are presumably the original CMIP5 projections, which were released several years ago.  It's definitely not the forcing-adjusted version. 

From the figure shown in this  post by Gavin Schmidt there seems to be a difference of about 0.1 C bewtween the two versions ( in 2013, pure eyeballing ).

Yes, it seems that currently there's a difference of about 0.1°C between the forcing-adjusted CMIP5 projection (thick black dashed line) and the original projection (black solid line):



This graph includes data up to 2015.  Source: https://climatecrocks.com/2016/01/20/graphs-of-the-day-the-pause-no-more
« Last Edit: May 04, 2016, 11:59:38 PM by Steven »

plinius

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Re: Global Surface Air Temperatures
« Reply #952 on: May 05, 2016, 12:23:19 AM »
To stress that point also @ Steven's post: The CMIP5 had to be adjusted because of the weak solar cycle (negative temperature impact) and because of some significant volcanic eruptions (again a negative temperature impact).  See here
http://www.nature.com/ngeo/journal/v7/n3/full/ngeo2105.html

And with the correct forcings (which nobody could know a priori, since humans still can't predict volcanoes), the CMIP5 models were spot on for the pretty neutral last year, and the current El Nino year, will be way above the model mean. So, no problem, the models match.

crandles

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Re: Global Surface Air Temperatures
« Reply #953 on: May 05, 2016, 12:18:52 PM »

And with the correct forcings (which nobody could know a priori, since humans still can't predict volcanoes), the CMIP5 models were spot on for the pretty neutral last year, and the current El Nino year, will be way above the model mean. So, no problem, the models match.

Hmm. 2016 above the where it should be, two very close or data ambiguous as to above or below where it should be and 15 below where it should be.

Or models don't predict timing of ENSO so ensemble mean removes those effect. If temps are adjusted for ENSO, that would reduce 2010 and 2015 temperatures and we will likely have 2016 above where you would expect and 17 previous years below where we would expect.

So a few way of looking at it:
1. Expect near 95% of years to be in the range. - Seems ok on this measure.
2. Expect near 50% above and near 50% below where expected. - 17:1 is not near 50% so models seem to be expecting too much warming.
3. Perhaps latest year should be given more weight as there is longer for the difference between actual and expected trend to show itself. - not as unbalanced as 17:1 under 2 but still one year can be a fluke and shouldn't balance out 17 indicating opposite direction.

Method 1 might take a long time before any discrepancy shows up so methods 2 or 3 may identify wrong warming rate problem sooner.

Quite a bit of scope to interpret differently from:

Models are alarmist expecting too much temperature change, to

Models don't include melt water cooling spots al la Hansen this might be evidence of this which can result in greater energy imbalances ....


AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #954 on: May 05, 2016, 05:09:04 PM »
Using RCP8.5, I calculate that the CMIP5 ensemble mean projection for 2016 was  0.95°C (relative to baseline 1951-1980) for global temperature, and 1.15°C for the Northern Hemisphere.   2016 will probably exceed those values, but of course it would be more meaningful to use an ENSO-neutral year (rather than a super El Nino year) to compare models vs. observations.


Steven,
Thank you for your thoughtful input.  Per my calculations from the following NH LOTI data, through the end of March 2016 the 12-month running average NH LOTI (1951-1980 baseline) is about 1.27C.  As you calculated a mean RCP 8.5 NH LOTI value for the end of 2016 of 1.15C,  or about 1.05C forcing adjusted (guessing 0.1C for the force adjustment); do you have any idea what the 95%CL value would be for the RCP 8.5 NH LOTI for the end of 2016 (assuming that even values influenced by a Super El Nino would be below the 95%CL value)?

N.HEMI Land-Ocean Temperature Index in 0.01 degrees Celsius, base period: 1951-1980

Year    Jan   Feb  Mar  Apr  May Jun   Jul  Aug  Sep  Oct  Nov  Dec 
2015   114  115  123  101   99  104   88   99  112  123  132  144   
2016   150  189  178  ***  *** ***  ***  *** ***  ***  ***  ***   
       
Divide by 100 to get changes in degrees Celsius (deg-C).

Best,
ASLR
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Steven

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Re: Global Surface Air Temperatures
« Reply #955 on: May 05, 2016, 09:26:14 PM »
Using RCP8.5, I calculate that the CMIP5 ensemble mean projection for 2016 was  0.95°C (relative to baseline 1951-1980) for global temperature, and 1.15°C for the Northern Hemisphere.   2016 will probably exceed those values, but of course it would be more meaningful to use an ENSO-neutral year (rather than a super El Nino year) to compare models vs. observations.


Steven,
Thank you for your thoughtful input.  Per my calculations from the following NH LOTI data, through the end of March 2016 the 12-month running average NH LOTI (1951-1980 baseline) is about 1.27C.  As you calculated a mean RCP 8.5 NH LOTI value for the end of 2016 of 1.15C,  or about 1.05C forcing adjusted (guessing 0.1C for the force adjustment); do you have any idea what the 95%CL value would be for the RCP 8.5 NH LOTI for the end of 2016 (assuming that even values influenced by a Super El Nino would be below the 95%CL value)?

N.HEMI Land-Ocean Temperature Index in 0.01 degrees Celsius, base period: 1951-1980

Year    Jan   Feb  Mar  Apr  May Jun   Jul  Aug  Sep  Oct  Nov  Dec 
2015   114  115  123  101   99  104   88   99  112  123  132  144   
2016   150  189  178  ***  *** ***  ***  *** ***  ***  ***  ***   
       
Divide by 100 to get changes in degrees Celsius (deg-C).

Best,
ASLR

Using baseline 1951-1980, and subtracting 0.1°C for the forcing adjustment, the CMIP5 projections for 2016 are:

Global average:           0.85°C   (95% CI:   0.5–1.2 °C)

Northern Hemisphere: 1.05°C   (95% CI:   0.6–1.5 °C)

Southern Hemisphere: 0.65°C   (95% CI:   0.3–1.0 °C)

(As mentioned, these projections don't take into account the 2016 ENSO/ super El Nino event.)
« Last Edit: May 05, 2016, 10:54:30 PM by Steven »

plinius

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Re: Global Surface Air Temperatures
« Reply #956 on: May 06, 2016, 12:33:26 AM »

And with the correct forcings (which nobody could know a priori, since humans still can't predict volcanoes), the CMIP5 models were spot on for the pretty neutral last year, and the current El Nino year, will be way above the model mean. So, no problem, the models match.

Hmm. 2016 above the where it should be, two very close or data ambiguous as to above or below where it should be and 15 below where it should be.

Or models don't predict timing of ENSO so ensemble mean removes those effect. If temps are adjusted for ENSO, that would reduce 2010 and 2015 temperatures and we will likely have 2016 above where you would expect and 17 previous years below where we would expect.

So a few way of looking at it:
1. Expect near 95% of years to be in the range. - Seems ok on this measure.
2. Expect near 50% above and near 50% below where expected. - 17:1 is not near 50% so models seem to be expecting too much warming.
3. Perhaps latest year should be given more weight as there is longer for the difference between actual and expected trend to show itself. - not as unbalanced as 17:1 under 2 but still one year can be a fluke and shouldn't balance out 17 indicating opposite direction.

Method 1 might take a long time before any discrepancy shows up so methods 2 or 3 may identify wrong warming rate problem sooner.

Quite a bit of scope to interpret differently from:

Models are alarmist expecting too much temperature change, to

Models don't include melt water cooling spots al la Hansen this might be evidence of this which can result in greater energy imbalances ....

There is no scope. The models fit the global temperature spot-on within the measurement and random noise accuracy. You can also remove the ENSO signal etc. (a la Foster & R.) and get the same result. All said.
Everything else is vain babble to no avail.

Michael Hauber

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Re: Global Surface Air Temperatures
« Reply #957 on: May 06, 2016, 02:15:59 AM »
The models fit the global temperature spot-on within the measurement and random noise accuracy. You can also remove the ENSO signal etc. (a la Foster & R.) and get the same result. All said.
Everything else is vain babble to no avail.

I agree models fit temperature close enough compared to accuracy and noise considerations.  Discussing the small differences that do exist is not vain babble, but may lead to learning something about the climate.
Climate change:  Prepare for the worst, hope for the best, expect the middle.

AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #958 on: May 06, 2016, 04:06:33 AM »
Using baseline 1951-1980, and subtracting 0.1°C for the forcing adjustment, the CMIP5 projections for 2016 are:

Global average:           0.85°C   (95% CI:   0.5–1.2 °C)

Northern Hemisphere: 1.05°C   (95% CI:   0.6–1.5 °C)

Southern Hemisphere: 0.65°C   (95% CI:   0.3–1.0 °C)

(As mentioned, these projections don't take into account the 2016 ENSO/ super El Nino event.)

Thanks, are these values/ranges for the end of June 2016 or for the end of December 2016?
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Steven

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Re: Global Surface Air Temperatures
« Reply #959 on: May 06, 2016, 02:43:06 PM »
are these values/ranges for the end of June 2016 or for the end of December 2016?

All these numbers are for the annual average (January to December).

AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #960 on: May 06, 2016, 04:53:45 PM »
The models fit the global temperature spot-on within the measurement and random noise accuracy. You can also remove the ENSO signal etc. (a la Foster & R.) and get the same result. All said.
Everything else is vain babble to no avail.

I agree models fit temperature close enough compared to accuracy and noise considerations.  Discussing the small differences that do exist is not vain babble, but may lead to learning something about the climate.

The linked article (and two associated images) discusses a new (more powerful) climate model evalution package to better determine just how accurate each new generation of projections are:

Peter J. Gleckler, Charles Doutriaux, Paul J. Durack, Karl E. Taylor, Yuying Zhang, Dean N. Williams, Erik Mason, and Jérôme Servonnat (May 2016), "A More Powerful Reality Test for Climate Models", EOS.

https://eos.org/project-updates/a-more-powerful-reality-test-for-climate-models


Extract: "Projections of climate change are based on theory, historical data, and results from physically based climate models. Building confidence in climate models and their projections involves quantitative comparisons of simulations with a diverse suite of observations. Climate modelers often consider information from well-established tests and comparisons among existing models to help decide on a new model version among multiple candidates.
Climate model developers and those who use these models benefit from sharing information with each other. Both groups require access to the best available data and rely on open source software tools designed to facilitate the analysis of climate data. Developers benefit the most from comparisons of their models with observations and other models when the results of such analysis can be made quickly available.
Here we introduce a new climate model evaluation package that quantifies differences between observations and simulations contributed to the World Climate Research Programme’s Coupled Model Intercomparison Project (CMIP). This package is designed to make an increasingly diverse suite of summary statistics more accessible to modelers and researchers."


Caption for first image: "(top) Observed and (bottom) simulated seasonal mean (December–January–February) 2-meter surface air temperature data. The observational estimate is taken from surface instrument records, and the model result in an ensemble average of results from more than 20 climate models contributed to the Coupled Model Intercomparison Project. Credit: Peter J. Gleckler/LLNL"

Caption for second image: "Fig. 1. The Coupled Model Intercomparison Project Phase 5 (CMIP5) facilitates the comparison of results from various climate models. Shown here are relative error measures of different developmental tests of the National Oceanic and Atmospheric Administration’s Geophysical Fluid Dynamics Laboratory (GFDL) model. Results are based on the global seasonal cycle climatology (1980–2005) computed from Atmospheric Model Intercomparison Project (AMIP) experiments. Rows and columns represent individual variables and models, respectively. The error measure is a spatial root-mean-square error (RMSE) that treats each variable separately. The color scale portrays this RMSE as a relative error by normalizing the result by the median error of all model results [Gleckler et al., 2008]. For example, a value of 0.20 indicates that a model’s RMSE is 20% larger than the median error for that variable across all simulations on the figure, whereas a value of –0.20 means the error is 20% smaller than the median error. The four triangles in grid square show the relative error with respect to the four seasons (in clockwise order, with December–January–February (DJF) at the top; MAM = March–April–May, JJA = June–July–August, and SON = September–October–November). The reference data sets are the default satellite and reanalysis data sets identified by Flato et al. [2013]. TOA = top of atmosphere, SW = shortwave, LW = longwave. Credit: Erik Mason/GFDL"
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AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #961 on: May 06, 2016, 04:59:38 PM »
are these values/ranges for the end of June 2016 or for the end of December 2016?

All these numbers are for the annual average (January to December).

Thanks.  As a 12-month running average through June 30 2016 would include data from 2015; each coming month I will post updated 12-month running averages from January 2016 through Dec 31 2016, so that towards the end of January 2017 we can see how we are trending compared to the CMIP5 RCP 8.5 95% CL range.
« Last Edit: May 06, 2016, 10:16:18 PM by AbruptSLR »
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AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #962 on: May 06, 2016, 11:03:09 PM »
The linked reference concludes that : "Our models also show that the ocean heat uptake is substantially driven by the natural component of the total radiative forcing at a decadal time scale, confining the importance of the anthropogenic influences to a longer range warming of the ocean."  Therefore, if heat was sequestered in the ocean during the recent faux hiatus (say from 1999 to 2014), then we can expect heat to come out of the ocean for a comparable duration into the future:

Antonello Pasini, Umberto Triacca and  Alessandro Attanasio (04 May 2016), "Evidence for the role of the Atlantic multidecadal oscillation and the ocean heat uptake in hiatus prediction", Theoretical and Applied Climatology, DOI 10.1007/s00704-016-1818-6


http://rd.springer.com/article/10.1007%2Fs00704-016-1818-6

Abstract: "The recent hiatus in global temperature at the surface has been analysed by several studies, mainly using global climate models. The common accepted picture is that since the late 1990s, the increase in anthropogenic radiative forcings has been counterbalanced by other factors, e.g., a decrease in natural forcings, augmented ocean heat storage and negative phases of ocean–atmosphere-coupled oscillation patterns. Here, simple vector autoregressive models are used for forecasting the temperature hiatus in the period 2001–2014. This gives new insight into the problem of understanding the ocean contribution (in terms of heat uptake and atmosphere–ocean-coupled oscillations) to the appearance of this recent hiatus. In particular, considering data about the ocean heat content until a depth of 700 m and the Atlantic multidecadal oscillation is necessary for correctly forecasting the hiatus, so catching both trend and interannual variability. Our models also show that the ocean heat uptake is substantially driven by the natural component of the total radiative forcing at a decadal time scale, confining the importance of the anthropogenic influences to a longer range warming of the ocean."
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AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #963 on: May 07, 2016, 09:42:19 PM »
I will post updated 12-month running averages from January 2016 through Dec 31 2016, so that towards the end of January 2017 we can see how we are trending compared to the CMIP5 RCP 8.5 95% CL range.

As it will be some time before the April GISS value is official, I provide the following comparison between the Global, NH & SH temperature departure values for: (a) the 2015 Mean values, (b) the approximate force adjusted CMIP5 2016 RCP 8.5 (and 95% CL range per Steven) and (c) the Jan./Feb./March 2016 12-month running average GISS temp departures (from 1951-1980).  This data shows that as compared to the RCP 8.5 CMIP5 2016 average mean value the March 2016 12-month running average is running hot in the NH, and cold in the SH, as would be expected if Hansen et al 2016 are correct and Antarctic glacial ice melting is cooling the air temperature 2m above the Southern Ocean.  It will be interesting to see if this trend continues through Dec 31 2016:

GISS Land & Ocean Temp Departure degrees Celsius, base period: 1951-1980

Year                              Global        NHem              SHem
2015 Mean   :                   0.86           1.13                0.60 
2016 RCP 8.5/CMIP5:       0.85            1.05              0.65
RCP 8.5 95% CL Range:  (0.5–1.2)     (0.6–1.5)         (0.3–1.0)

12-mo.running ave.
March 2016:                    0.90             1.27               0.61
Febr. 2016:                     0.87               1.22              0.60
Jan. 2016:                       0.83              1.16               0.58

(The concert 1951-1980 temp departures to pre-industrial add: + 0.256 Celsius)
« Last Edit: May 07, 2016, 09:47:58 PM by AbruptSLR »
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AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #964 on: May 08, 2016, 01:38:11 AM »
Per the following linked peer reviewed reference Pauling et al (2016): "The freshwater flux from ice sheet and ice shelf mass imbalance is largely missing in models that participated in phase 5 of the Coupled Model Intercomparison Project (CMIP5). However, on average, precipitation minus evaporation (P − E) reaching the Southern Ocean has increased in CMIP5 models to a present value that is about 2600 Gt/yr greater than preindustrial times and 5–22 times larger than estimates of the mass imbalance of Antarctic ice sheets and shelves (119–544 Gt/yr)."

Hopefully, future CMIP programs will not largely dismiss the impact of such an important physical phenomenon:

http://journals.ametsoc.org/doi/10.1175/JCLI-D-15-0501.1
« Last Edit: May 09, 2016, 06:56:47 PM by AbruptSLR »
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AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #965 on: May 08, 2016, 03:29:15 AM »
For what it is worth, the two attached temperature anom forecasts indicate that the NH and Antarctica are abnormally warm, while the SH is abnormally cool; which implies that the Southern Ocean is unusually cool (for this time of year):
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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magnamentis

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Re: Global Surface Air Temperatures
« Reply #966 on: May 08, 2016, 03:04:36 PM »
........while the SH is abnormally cool;

what makes you think so, is there a misunderstanding, see attached image from same source and it was like that the previous days?

crandles

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Re: Global Surface Air Temperatures
« Reply #967 on: May 08, 2016, 03:35:57 PM »
https://www.ncdc.noaa.gov/cag/time-series/global/shem/ocean/1/3/1880-2016

Southern hemisphere ocean anomaly for March 2016 0.83C (vs 20th century average) next warmest March was 2010 at 0.63C.

Feb 2016 0.77C vs Feb 2010 0.61C. Would expect it to take a while to close that gap even with El Nino fading.

AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #968 on: May 08, 2016, 05:12:52 PM »
........while the SH is abnormally cool;

what makes you think so, is there a misunderstanding, see attached image from same source and it was like that the previous days?

I mean abnormally cool as compared to the SH force adjusted CMIP5 RCP 8.5 projection (provided by Steven in Reply #959).
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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magnamentis

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Re: Global Surface Air Temperatures
« Reply #969 on: May 08, 2016, 05:36:24 PM »
thanks for the further clarification.

Sigmetnow

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Re: Global Surface Air Temperatures
« Reply #970 on: May 09, 2016, 08:10:59 PM »
New graphic shows spiraling global temperatures. 
Click on the image in the link to see an enlarged, animated version.

http://www.climate-lab-book.ac.uk/2016/spiralling-global-temperatures/
People who say it cannot be done should not interrupt those who are doing it.

TerryM

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Re: Global Surface Air Temperatures
« Reply #971 on: May 09, 2016, 10:38:41 PM »
The above is a VERY POWERFUL graph. Hopefully it gets more exposure.
Thanks Sig
Terry

AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #972 on: May 12, 2016, 05:01:29 PM »
The linked reference confirms that internal climate variability (ICV) influences NH land SAT anomalies in approximately 20-year cycles.  Thus 1978-1998 exhibited above average NH warming while 1999 to 2014 exhibited below average warming; and now we are experiencing another period of accelerated warming over NH land.

Jianping Huang, Yongkun Xie, Xiaodan Guan, Dongdong Li & Fei Ji (09 May 2016), "The dynamics of the warming hiatus over the Northern Hemisphere", Climate Dynamics, pp 1-18; DOI: 10.1007/s00382-016-3085-8

http://rd.springer.com/article/10.1007%2Fs00382-016-3085-8

Abstract: "A warming hiatus is a period of relatively little change in global mean surface air temperatures (SAT). Many studies have attributed the current warming hiatus to internal climate variability (ICV). But there is less work on discussion of the dynamics about how these ICV modes influence cooling over land in the Northern Hemisphere (NH). Here we demonstrate the warming hiatus was more significant over the continental NH. We explored the dynamics of the warming hiatus from a global perspective and investigated the mechanisms of the reversing from accelerated warming to hiatus, and how ICV modes influence SAT change throughout the NH land. It was found that these ICV modes and Arctic amplification can excite a decadal modulated oscillation (DMO), which enhances or suppresses the long-term trend on decadal to multi-decadal timescales. When the DMO is in an upward (warming) phase, it contributes to an accelerated warming trend, as in last 20 years of twentieth-century. It appears that there is a downward swing in the DMO occurring at present, which has balanced or reduced the radiative forced warming and resulted in the recent global warming hiatus. The DMO modulates the SAT, in particular, the SAT of boreal cold months, through changes in the asymmetric meridional and zonal thermal forcing (MTF and ZTF). The MTF represents the meridional temperature gradients between the mid- and high-latitudes, and the ZTF represents the asymmetry in temperatures between the extratropical large-scale warm and cold zones in the zonal direction. Via the different performance of combined MTF and ZTF, we found that the DMO’s modulation effect on SAT was strongest when both weaker (stronger) MTF and stronger (weaker) ZTF occurred simultaneously. And the current hiatus is a result of a downward DMO combined with a weaker MTF and stronger ZTF, which stimulate both a weaker polar vortex and westerly winds, along with the amplified planetary waves, thereby facilitating southward invasion of cold Arctic-air and promoting the blocking formation. The results conclude that the DMO can not only be used to interpret the current warming hiatus, it also suggests that global warming will accelerate again when it swings upward."


The significance of this fact can be seen in that rapid acceleration in 2015-2016 of these values per the linked NOAA time-series:

http://www.ncdc.noaa.gov/cag/time-series/global/globe/land/p12/12/1880-2016.csv

Global Land Temperature Anomalies
Units: Degrees Celsius
Base Period: 1901-2000

Year,     Value
201501,1.3869
201502,1.6914
201503,1.6237
201504,1.0811
201505,1.2247
201506,1.2353
201507,0.9459
201508,1.1241
201509,1.1514
201510,1.3093
201511,1.2969
201512,1.8783
201601,1.5675
201602,2.2665
201603,2.3305
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Michael Hauber

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Re: Global Surface Air Temperatures
« Reply #973 on: May 13, 2016, 01:49:38 AM »
The linked reference confirms that internal climate variability (ICV) influences NH land SAT anomalies in approximately 20-year cycles.  Thus 1978-1998 exhibited above average NH warming while 1999 to 2014 exhibited below average warming; and now we are experiencing another period of accelerated warming over NH land.

Jianping Huang, Yongkun Xie, Xiaodan Guan, Dongdong Li & Fei Ji (09 May 2016), "The dynamics of the warming hiatus over the Northern Hemisphere", Climate Dynamics, pp 1-18; DOI: 10.1007/s00382-016-3085-8

http://rd.springer.com/article/10.1007%2Fs00382-016-3085-8


It comes down to what they've called DMO index which is a composite of PDO + ENSO + AMO, with a small amount of AO added in as well.  The AMO has been increasing (They use the alternative Trenberth definition), so the hiatus in this analysis basically comes down to PDO + ENSO.  As the AMO has been warming while PDO has cooled, the recent drop in DMO is from high values to near normal values.

An upward swing in the DMO index would have to be driven by the PDO and ENSO indexes.  As these indexes have been about as warm as they can possibly get in the last 12 months we may have seen as much warming due to PDO and ENSO as we are ever going to see, and the only way forward is down again. 

If the PDO and ENSO were to return to cool values, and the AMO drop, we could see the recent reduction in the DMO index extend for another 10 or 20 years and double the drop that has occurred so far.
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AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #974 on: May 13, 2016, 04:18:34 AM »
The linked reference confirms that internal climate variability (ICV) influences NH land SAT anomalies in approximately 20-year cycles.  Thus 1978-1998 exhibited above average NH warming while 1999 to 2014 exhibited below average warming; and now we are experiencing another period of accelerated warming over NH land.

Jianping Huang, Yongkun Xie, Xiaodan Guan, Dongdong Li & Fei Ji (09 May 2016), "The dynamics of the warming hiatus over the Northern Hemisphere", Climate Dynamics, pp 1-18; DOI: 10.1007/s00382-016-3085-8

http://rd.springer.com/article/10.1007%2Fs00382-016-3085-8


It comes down to what they've called DMO index which is a composite of PDO + ENSO + AMO, with a small amount of AO added in as well.  The AMO has been increasing (They use the alternative Trenberth definition), so the hiatus in this analysis basically comes down to PDO + ENSO.  As the AMO has been warming while PDO has cooled, the recent drop in DMO is from high values to near normal values.

An upward swing in the DMO index would have to be driven by the PDO and ENSO indexes.  As these indexes have been about as warm as they can possibly get in the last 12 months we may have seen as much warming due to PDO and ENSO as we are ever going to see, and the only way forward is down again. 

If the PDO and ENSO were to return to cool values, and the AMO drop, we could see the recent reduction in the DMO index extend for another 10 or 20 years and double the drop that has occurred so far.

The authors conclude that they expect the DMO (decadal modulated oscillation) to increase (compared to the recent faux hiatus) in the near future, not decrease.
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Michael Hauber

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Re: Global Surface Air Temperatures
« Reply #975 on: May 13, 2016, 08:05:44 AM »

The authors conclude that they expect the DMO (decadal modulated oscillation) to increase (compared to the recent faux hiatus) in the near future, not decrease.

They give no reason for why they expect the DMO to increase in the future.

Is the DMO currently at the bottom, top or middle of its cycle?  I can't tell from the data they present.

Fig 4 shows the DMO as a constantly positive value with hints of a cycle that we may or may not be near the bottom of - it is almost impossible to tell where the cycle would normally start or end.  It also shows the temperature history as DMO + Trend where the trend works out at about 0.4 degrees of warming from 1975 to 2015, same as HADCRUT SAT, and then DMO + trend = 0.6 degrees of warming.  Are they trying to claim here that SST trend + DMO = land + ocean trend?

Figure 5 shows the DMO component of NH SST is near 0, and is only about halfway through its downward cycle if the current cycle repeats the last cycle.

Figure 6a seems to be the same as 5, and figure 6b shows DMO for NH SST, but calculated using a different method, which shows that DMO has only just barely passed the peak of its cycle.
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Re: Global Surface Air Temperatures
« Reply #976 on: May 13, 2016, 05:16:24 PM »

They give no reason for why they expect the DMO to increase in the future.


While you can always say that the future is data poor; nevertheless, the DMO is heavily influenced by the PDO which is current very positive (see the following data):

PDO Index
YEAR  JAN    FEB    MAR   APR    MAY   JUN   JUL    AUG    SEP   OCT    NOV   DEC
2014   0.30   0.38   0.97   1.13   1.80   0.82   0.70   0.67   1.08   1.49   1.72   2.51
2015   2.45   2.30   2.00   1.44   1.20   1.54   1.84   1.56   1.94   1.47   0.86   1.01
2016   1.53   1.75   2.40

Also, the ENSO is still in an El Nino condition and the attached plot indicates that the AO is forecast to become meaningfully positive soon; which, indicates that the DMO is likely positive now.
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Re: Global Surface Air Temperatures
« Reply #977 on: May 13, 2016, 09:40:14 PM »

While you can always say that the future is data poor; nevertheless, the DMO is heavily influenced by the PDO which is current very positive (see the following data):

PDO Index
YEAR  JAN    FEB    MAR   APR    MAY   JUN   JUL    AUG    SEP   OCT    NOV   DEC
2014   0.30   0.38   0.97   1.13   1.80   0.82   0.70   0.67   1.08   1.49   1.72   2.51
2015   2.45   2.30   2.00   1.44   1.20   1.54   1.84   1.56   1.94   1.47   0.86   1.01
2016   1.53   1.75   2.40

Also, the ENSO is still in an El Nino condition and the attached plot indicates that the AO is forecast to become meaningfully positive soon; which, indicates that the DMO is likely positive now.

Which was my original point.  If its positive now, it should be expected to go down in the future.

Of course the data analysis in the paper does not include the recent upward jump in ENSO and PDO, so the jump we just had could be seen as being the increase forecast in this paper, even though it occurred prior to the paper being published.
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Re: Global Surface Air Temperatures
« Reply #978 on: May 14, 2016, 04:31:32 PM »
Which was my original point.  If its positive now, it should be expected to go down in the future.


The linked article 2014 SciAm article by Michael Mann indicates (see images) that models project that assuming an ECS of 3C, that the NH land temperatures would not exceed 2C until 2036; however, if we keep following the trend for NOAA SAT departures cited in Reply #976 we may well cross this 12-month NH 2C threshold by the end of 2016.  At that point you will need to ask yourself whether this is because ECS is actually 4.5 to 5C, or because the DMO is significantly positive (or both):

http://www.scientificamerican.com/article/mann-why-global-warming-will-cross-a-dangerous-threshold-in-2036/

Extract: "Why Global Warming Will Cross a Dangerous Threshold in 2036
Emitting carbon dioxide at current rates will soon push Earth’s temperature up by 2 degrees Celsius. Here’s how to make the calculation yourself"
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BornFromTheVoid

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Re: Global Surface Air Temperatures
« Reply #979 on: May 14, 2016, 10:15:18 PM »
The April GISS data is out. At +1.11C above the 51-80 average, it is the warmest on record, beating the 2010 value of +0.87C.



Meanwhile, the 12 month rolling average is now up to +0.994C, so just shy of the 1C mark.



Anything over +0.85C for May should send the 12 month average above 1C.
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Re: Global Surface Air Temperatures
« Reply #980 on: May 15, 2016, 02:50:20 AM »
NOAA's NCDC provides some rather extreme statistics about both March, and the Jan-March, 2016 periods:

http://www.ncdc.noaa.gov/sotc/global/201603
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Re: Global Surface Air Temperatures
« Reply #981 on: May 15, 2016, 04:14:38 AM »
I provide the following comparison between the Global, NH & SH GISS Land & Ocean temperature departure values for: (a) the 2015 Mean values, (b) the approximate force adjusted CMIP5 2016 RCP 8.5 (and 95% CL range per Steven) and (c) the Jan./Feb./March/April 2016 12-month running average GISS temp departures (from 1951-1980).  This data shows that as compared to the RCP 8.5 CMIP5 2016 average mean value the April 2016 12-month running average Global, NH and SH are all running hot.  It will be interesting to see if this trend continues through Dec 31 2016:

GISS Land & Ocean Temp Departure degrees Celsius, base period: 1951-1980

Year                             Global         NHem        SHem
2015 Mean                      0.86         1.13          0.60 
2016 RCP 8.5/CMIP5        0.85         1.05           0.65
RCP 8.5 95% CL Range (0.5–1.2)   (0.6–1.5)    (0.3–1.0)

12-mo. running ave.
April 2016:                    0.99           1.30            0.69
March 2016:                  0.96           1.27           0.66
Febr. 2016:                   0.93            1.22            0.64
Jan. 2016:                     0.89            1.16            0.62
(To convert 1951-1980 temp departures to pre-industrial add: + 0.256 Celsius)

http://data.giss.nasa.gov/gistemp/tabledata_v3/NH.Ts+dSST.txt
http://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts+dSST.txt
http://data.giss.nasa.gov/gistemp/tabledata_v3/SH.Ts+dSST.txt
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bbr2314

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Re: Global Surface Air Temperatures
« Reply #982 on: May 15, 2016, 09:56:56 AM »
All of the models show temps 5-10C+ above normal over Pakistan and India through D10+. This heatwave also comes with moisture. Does anyone have insight into how unprecedented the forecast is?

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Re: Global Surface Air Temperatures
« Reply #983 on: May 16, 2016, 12:57:12 PM »
April breaks global temperature record, marking seven months of new highs
Latest monthly figures add to string of recent temperature records and all but assure 2016 will be hottest year on record.
Quote
The latest figures smashed the previous record for April by the largest margin ever recorded.

It makes three months in a row that the monthly record has been broken by the largest margin ever, and seven months in a row that are at least 1C above the 1951-80 mean for that month. When the string of record-smashing months started in February, scientists began talking about a “climate emergency”.
http://www.theguardian.com/environment/2016/may/16/april-third-month-in-row-to-break-global-temperature-records
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Re: Global Surface Air Temperatures
« Reply #984 on: May 17, 2016, 12:24:39 AM »
SkS has updated their 2C Tracker through April 2016, and they indicate that the 12-month running average (baseline to pre-industrial or 1880 - 1909) has increased up to +1.246C (note that at the end of March 2016 this value was +1.210C.  Also I note that per Reply #985 the 12-month running average thru April baselined to 1951-1980 is+0.99, which is equal to 0.99 + 0.256 = +1.246C, baselined to 1880-1909, as indicated by SkS):
« Last Edit: May 17, 2016, 12:36:54 AM by AbruptSLR »
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crandles

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Re: Global Surface Air Temperatures
« Reply #985 on: May 17, 2016, 03:31:45 PM »
At http://moyhu.blogspot.co.uk/2016/05/april-giss-down-0.html?showComment=1463309028441#c8145856349843453603

Olof R says
Slightly colder than expected (by me), but at least a tie with January for third warmest monthly anomaly ever.
Quote
The GHCNv3 Arctic cooling sickness has unfortunately spread, and includes now also Svalbard. The algorithm finds the persistent hotspot spurious (6 months with about +10 C anomaly since Nov 2015 over Svalbard, Franz Josef and Ostrov Vize Islands), and has simply removed the data.
However, I don't think the global effect of this Arctic adjustment is very large, maybe -0.02 C, which can be seen in record high February which has slipped down from 1.35 to 1.33 C.
The effect of station adjustment kan be studied here
Typically GHCNv3 removes about 600 stations worlwide each month, or about 25% of the total. In areas with redundancy this doesn't matter, but areas where stations are more sparse (e g Brazil and parts of Africa) are affected as well

Is this true that stations are being removed because they have 6 consecutive months of +10C anomaly?

I can imagine that it made sense when originally included (as Kevin O'Neill said at http://dosbat.blogspot.co.uk/2016/05/giss-april.html ). Now causing (a fairly minor cooling) bias and time for this to be updated, do you think?

AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #986 on: May 17, 2016, 04:48:29 PM »
Scribbler has a nice article on our current situation; however, he fails to point out that NASA is capping extreme values (ala Olof R) and that cool spots in both the North Atlantic and the Southern Ocean are artificially suppressing increases in GMST departures:

https://robertscribbler.com/2016/05/16/nasa-world-just-had-seven-months-straight-of-record-shattering-global-heat/

Extract: "Last month was the hottest April in the global climate record. Not only was it the hottest such month ever recorded — it smashed the previous record by the largest margin ever recorded. And this April has now become the seventh month in a row in an unbroken chain of record global heat."
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Re: Global Surface Air Temperatures
« Reply #987 on: May 17, 2016, 05:29:48 PM »
Given that Hansen et al (2016)'s ice-climate feedback mechanism is already active (see the first two images of the CCI-Reanalyzer SH & NH GMST departure 5-day forecast issued May 17, respectively, and the third image of Karsten Haustein's GMST departure forecast from May 17 to 24 2016), it is my opinion that observing global mean surface temperature departures is no longer an acceptable measure of climate change.  Therefore, does anyone have a link to current monthly data monitoring Earth Energy Imbalance as shown by the fourth image through 2009?
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AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #988 on: May 17, 2016, 11:19:54 PM »
I provide the following comparison between the Global, NH & SH GISS Land & Ocean temperature departure values for: (a) the 2015 Mean values, (b) the approximate force adjusted CMIP5 2016 RCP 8.5 (and 95% CL range per Steven) and (c) the Jan./Feb./March/April 2016 12-month running average GISS temp departures (from 1951-1980).  This data shows that as compared to the RCP 8.5 CMIP5 2016 average mean value the April 2016 12-month running average Global, NH and SH are all running hot.  It will be interesting to see if this trend continues through Dec 31 2016:

GISS Land & Ocean Temp Departure degrees Celsius, base period: 1951-1980

Year                             Global         NHem        SHem
2015 Mean                      0.86         1.13          0.60 
2016 RCP 8.5/CMIP5        0.85         1.05           0.65
RCP 8.5 95% CL Range (0.5–1.2)   (0.6–1.5)    (0.3–1.0)

12-mo. running ave.
April 2016:                    0.99           1.30            0.69
March 2016:                  0.96           1.27           0.66
Febr. 2016:                   0.93            1.22            0.64
Jan. 2016:                     0.89            1.16            0.62
(To convert 1951-1980 temp departures to pre-industrial add: + 0.256 Celsius)

http://data.giss.nasa.gov/gistemp/tabledata_v3/NH.Ts+dSST.txt
http://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts+dSST.txt
http://data.giss.nasa.gov/gistemp/tabledata_v3/SH.Ts+dSST.txt

If we maintain the current 2016 rate of increase for the GISS GMST departure, then we will exceed the CMIP5 RCP 8.5 95%CL range by the end of November 2016 (i.e. we will be above the 2.5% probability range on the fat-tailed PDF). Furthermore, if we continue the current 2016 rate of increase for the GISS NH departures, then we will exceed the CMIP5 RCP 8.5 95%CL range before the end of October 2016.
« Last Edit: May 17, 2016, 11:26:39 PM by AbruptSLR »
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BornFromTheVoid

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Re: Global Surface Air Temperatures
« Reply #989 on: May 18, 2016, 10:16:00 AM »
We will be hosting an AMA today on reddit.com/r/science with folks from Climate Central and the Weather Channel. When the AMA is live, I'll add a link in here.

Here's the intro:

"Hi, we're Bernadette Woods Placky and Brian Kahn from Climate Central and Carl Parker, a hurricane specialist from the Weather Channel. The last 11 months in a row have been some of the most abnormally warm months the planet has ever experienced and are toeing close to the 1.5°C warming threshold laid out by the United Nations as an important climate milestone.

We've been keeping an eye on the record-setting temperatures as well as some of the impacts from record-low sea ice to a sudden April meltdown in Greenland to coral bleaching in the Great Barrier Reef. We're here to answer your questions about the global warming hot streak the planet is currently on, where we're headed in the future and our new Twitter hashtag for why these temperatures are #2hot2handle.

We will be back at 3 pm ET to answer your questions, Ask us anything!"
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Re: Global Surface Air Temperatures
« Reply #990 on: May 18, 2016, 02:08:48 PM »
The AMA is now live https://www.reddit.com/r/science/comments/4jwao6/science_ama_series_were_weather_and_climate/
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Re: Global Surface Air Temperatures
« Reply #991 on: May 18, 2016, 02:53:53 PM »
The AMA is now live https://www.reddit.com/r/science/comments/4jwao6/science_ama_series_were_weather_and_climate/

Already there appears to be an interesting mix of denier, believer, and genuine-seeker-of-knowledge questions.  I am heartened that more seem to be the latter types, and fewer questioning/denying the science.
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Re: Global Surface Air Temperatures
« Reply #992 on: May 18, 2016, 03:04:37 PM »
The AMA is now live https://www.reddit.com/r/science/comments/4jwao6/science_ama_series_were_weather_and_climate/

Already there appears to be an interesting mix of denier, believer, and genuine-seeker-of-knowledge questions.  I am heartened that more seem to be the latter types, and fewer questioning/denying the science.

We have a strict moderation policy on /r/science. Anything that runs counter to well established science has to provide peer reviewed evidence, otherwise, it's removed. We also have many known climate change deniers on reddit tagged and automoderator set up to auto-remove their comments.

Of the 79 comments so far, 18 have been removed.
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Re: Global Surface Air Temperatures
« Reply #993 on: May 18, 2016, 03:45:53 PM »
It's very important that you are doing an AMA! Reddit is a great place to communicate.

I'll give you an upvote!

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Re: Global Surface Air Temperatures
« Reply #994 on: May 18, 2016, 04:15:25 PM »
Cheers! The science AMA series has come a long way in the last year or so. We're flooded with requests for them nowadays!

Anywho, despite what I said earlier, we do leave up respectful comments and questions from deniers too though, such as this https://www.reddit.com/r/science/comments/4jwao6/science_ama_series_were_weather_and_climate/d3a6ufh

It's generally when someone has a proven track record as a denier or are disrespectful that we'll remove their comments.
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Re: Global Surface Air Temperatures
« Reply #995 on: May 18, 2016, 05:26:47 PM »
NOAA has updated its Land-Ocean GMST departures & April was warmer than January 2016:

http://www.ncdc.noaa.gov/cag/time-series/global/globe/land_ocean/p12/12/1880-2016.csv

Global Land and Ocean Temperature Anomalies
Units: Degrees Celsius
Base Period: 1901-2000
Year,   Value
201510,0.9877
201511,0.9657
201512,1.1221
201601,1.0345
201602,1.1944
201603,1.2297
201604,1.1028
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AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #996 on: May 18, 2016, 05:33:26 PM »
NOAA has updated its Land GMST departures & April was warmer than both January 2016 and December 2015.  As compared to the Land-Ocean values provided in my immediate prior post, the very high April land value indicates to me that the cool spots in the Southern Ocean due to glacial ice melting is distorting the Land-Ocean values to be lower than they otherwise would be without the ice-climate feedback, identified by Hansen et al 2016:

http://www.ncdc.noaa.gov/cag/time-series/global/globe/land/p12/12/1880-2016.csv

Global Land Temperature Anomalies
Units: Degrees Celsius
Base Period: 1901-2000
Year,   Value
201510,1.3314
201511,1.2992
201512,1.8803
201601,1.5460
201602,2.2841
201603,2.3803
201604,1.9315
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crandles

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Re: Global Surface Air Temperatures
« Reply #997 on: May 18, 2016, 06:04:17 PM »
Quote
The combined average temperature over global land and ocean surfaces for April 2016 was 1.10°C (1.98°F) above the 20th century average of 13.7°C (56.7°F)—the highest temperature departure for April since global records began in 1880. This value surpassed the previous record set in 2010 by 0.28°C (0.50°F). This was also the fourth highest monthly temperature departure among all 1,636 months on record, behind March 2016 (1.23°C/2.21°F), February 2016 (1.19°C/2.14°F), and December 2015 (1.12°C/2.02°F). Overall, 13 out of the 15 highest monthly temperature departures in the record have all occurred since February 2015, with February 1998 and January 2007 among the 15 highest monthly temperature departures. April 2016 also marks the fifth consecutive month (since December 2015) that the global monthly temperature departure from average has surpassed 1.0°C (1.8°F) and it is the 12th consecutive month a monthly global temperature record has been broken, the longest such streak in NOAA's 137 years of record keeping.
https://www.ncdc.noaa.gov/sotc/global/201604

AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #998 on: May 18, 2016, 06:10:13 PM »
Quote
The combined average temperature over global land and ocean surfaces for April 2016 was 1.10°C (1.98°F) above the 20th century average of 13.7°C (56.7°F)—the highest temperature departure for April since global records began in 1880. This value surpassed the previous record set in 2010 by 0.28°C (0.50°F). This was also the fourth highest monthly temperature departure among all 1,636 months on record, behind March 2016 (1.23°C/2.21°F), February 2016 (1.19°C/2.14°F), and December 2015 (1.12°C/2.02°F). Overall, 13 out of the 15 highest monthly temperature departures in the record have all occurred since February 2015, with February 1998 and January 2007 among the 15 highest monthly temperature departures. April 2016 also marks the fifth consecutive month (since December 2015) that the global monthly temperature departure from average has surpassed 1.0°C (1.8°F) and it is the 12th consecutive month a monthly global temperature record has been broken, the longest such streak in NOAA's 137 years of record keeping.
https://www.ncdc.noaa.gov/sotc/global/201604

As I noted Ocean values appear to be being artificially suppressed by ice sheet meltwater, thus while NOAA's Land-Ocean monthly temperature departure for April 2016 was only the fourth warmest for any month on record, NOAA's Land month temperature departure for April 2016 was the third warmest for any month on record.

Edit: As further evidence that glacial ice melting is distorting GMST departures, I offer the attached Karsten Haustein plot issued May 18 2016, that shows the SH (dominated by the Southern Ocean) is projected to drop below the 1981-2010 average in May (while the NH [dominated by land mass] values in May are projected to warm rapidly in the same period).
« Last Edit: May 18, 2016, 06:17:43 PM by AbruptSLR »
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Tor Bejnar

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Re: Global Surface Air Temperatures
« Reply #999 on: May 18, 2016, 07:47:32 PM »
ASLR,
Several times you written things like Ocean surface temperature "values appear to be being artificially suppressed by ice sheet meltwater". 

It certainly makes sense to me that melted ice will cool the sea water it finds itself mixing with.  I question your writing about the "artificiality" of this.  To the extent ACC is artificial, this process that is integral to CC will also be artificial.  But as I see CC as a natural response to ongoing anthropogenic activities, I see this melt water affect on sea surface temperatures as being natural too, and not the least bit artificial.

Am I missing something?  (and if so, what - and thanks for writing about this feature of climate change)
Arctic ice is healthy for children and other living things because "we cannot negotiate with the melting point of ice"