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The Chief

climber
Laughing at all you angry blinded asshat Sheep
Sep 15, 2014 - 04:00pm PT
Got a source NORTON???


NOAA, which is one of GISS's primary sources of data, will not release the monthly Global State of the Climate Report for the month of August 2014 till this Thursday.
http://www.ncdc.noaa.gov/monitoring-references/dyk/monthly-releases

First of all, GISS's US temps do NOT jive one bit with NOAA's for the month of August 2014.

WTF is up with that??


Much of the contiguous U.S. had near-average August temperatures. However, above-average temperatures were observed along the West Coast, Florida, and parts of New England. Florida had its sixth warmest August on record and Washington had its seventh warmest. Below-average temperatures were observed in parts of the Southwest and the Mid-Atlantic. Virginia had its 10th coolest August on record.

NOAA: http://www.ncdc.noaa.gov/sotc/service/national/Statewidetrank/201408-201408.gif





GISS's:(Look at the US) http://data.giss.nasa.gov/cgi-bin/gistemp/nmaps.cgi?sat=4&sst=3&type=trends&mean_gen=08&year1=1880&year2=2014&base1=1951&base2=1980&radius=1200&pol=rob




Which one of the two above are spraying bullshet outta their asses?

monolith

climber
SF bay area
Sep 15, 2014 - 04:12pm PT
Direct from Goddard Institute of Space Sciences.

Hottest August.

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

The Chief

climber
Laughing at all you angry blinded asshat Sheep
Sep 15, 2014 - 04:15pm PT
So MONO, please do explain the obvious disparity which I just posted above.


GISS's August Temps for the US do not jive on bit with those from NOAA.


Going to be rather interesting to see where NOAA/CDC puts August globally this coming Thursday.


You all better hope they match up.


Much of the contiguous U.S. had near-average August temperatures. However, above-average temperatures were observed along the West Coast, Florida, and parts of New England. Florida had its sixth warmest August on record and Washington had its seventh warmest. Below-average temperatures were observed in parts of the Southwest and the Mid-Atlantic. Virginia had its 10th coolest August on record.

NOAA: http://www.ncdc.noaa.gov/sotc/service/national/Statewidetrank/201408-201408.gif





GISS's:(Look at the US) http://data.giss.nasa.gov/cgi-bin/gistemp/nmaps.cgi?sat=4&sst=3&type=trends&mean_gen=08&year1=1880&year2=2014&base1=1951&base2=1980&radius=1200&pol=rob




monolith

climber
SF bay area
Sep 15, 2014 - 04:17pm PT
LOL! It's hilarious how you can discern temp from those pics.

Why don't you go whine on Steven Goddard's site.

He also thinks it's a big conspiracy.
The Chief

climber
Laughing at all you angry blinded asshat Sheep
Sep 15, 2014 - 04:20pm PT
No conspiracy.


Just goes to show ya how the supposedly top two CC data sources from the US are showing some pretty large differences in their data.

The irony is that GISS gathers their US temps from the exact same source as does NOAA.
monolith

climber
SF bay area
Sep 15, 2014 - 04:23pm PT
No, irony, idiot.

Each agency uses it's own homogenizing algorithms. They are a good check on each other.
The Chief

climber
Laughing at all you angry blinded asshat Sheep
Sep 15, 2014 - 04:28pm PT
Homogenized.. bullshet.



More like "manipulated/tweeked".



How can you homogenize the exact same data taken from the exact same sources and come up with drastically different results.

Again, take a look at the US from both entities for the month of August.



Much of the contiguous U.S. had near-average August temperatures. However, above-average temperatures were observed along the West Coast, Florida, and parts of New England. Florida had its sixth warmest August on record and Washington had its seventh warmest. Below-average temperatures were observed in parts of the Southwest and the Mid-Atlantic. Virginia had its 10th coolest August on record.

NOAA: http://www.ncdc.noaa.gov/sotc/service/national/Statewidetrank/201408-201408.gif





GISS's:(Look at the US) http://data.giss.nasa.gov/cgi-bin/gistemp/nmaps.cgi?sat=4&sst=3&type=trends&mean_gen=08&year1=1880&year2=2014&base1=1951&base2=1980&radius=1200&pol=rob







Splater

climber
Grey Matter
Sep 15, 2014 - 04:29pm PT
Gordon Fulks sums it up well: “CO2 is said to be responsible for global warming that is not occurring, for accelerated sea-level rise that is not occurring, for net glacial and sea ice melt that is not occurring . . . and for increasing extreme weather that is not occurring.”

WRONG

"Consider:
• According to NASA satellites and all ground-based temperature measurements, global warming ceased in the late 1990s. This when CO2 levels have risen almost 10 percent since 1997. The post-1997 CO2 emissions represent an astonishing 30 percent of all human-related emissions since the Industrial Revolution began. That we’ve seen no warming contradicts all CO2-based climate models upon which global-warming concerns are founded."

WRONG, WHERE is Fulks model that disproves the common theory that the excess heat is going into the oceans?

"•Rates of sea-level rise remain small and are even slowing, over recent decades averaging about 1 millimeter per year as measured by tide gauges and 2 to 3 mm/year as inferred from “adjusted” satellite data. Again, this is far less than what the alarmists suggested."

WRONG. Sea level rise is Accelerating.

• Satellites also show that a greater area of Antarctic sea ice exists now than any time since space-based measurements began in 1979. In other words, the ice caps aren’t melting.

WRONG
the Arctic and Greenland show the most obvious ice change, as you would expect looking at any climate map where you see it is the north that is heating the most.
Antarctica is more of a special case. Volume does not equal area, so in the Antarctic, it is likely that decreasing volume can lead to more icebergs, so you have melting at the same time ice extent can increase a little.
Global Ice Extent and Total : are both DECREASING

"• A 2012 IPCC report concluded that there has been no significant increase in either the frequency or intensity of extreme weather events in the modern era. The NIPCC 2013 report concluded the same. Yes, Hurricane Sandy was devastating — but it’s not part of any new trend."

WE DON'T yet know what will be the new trend. Past performance is not indicative of the future. The predictions are still that hotter weather and SST will drive more weather events in the FUTURE.

"The climate scare, Fulks sighs, has “become a sort of societal pathogen that virulently spreads misinformation in tiny packages like a virus.”"

WRONG,
DENIALISTS are the ones who make a career of Misinformation.
monolith

climber
SF bay area
Sep 15, 2014 - 04:34pm PT
No conspiracy.

More like "manipulated/tweeked".

LOL!
guyman

Social climber
Moorpark, CA.
Sep 15, 2014 - 04:36pm PT
OK, I change my mind..... it's hotter than I can ever recall at Stoney right now.

So this January when the price of gas goes up .15/gal, I will thank Gov Schanegger for starting us all on the true path to clean air, healthy life and a brighter future for all of the living creatures on the planet.

Thanks Gov....

we don't miss you.
Norton

Social climber
quitcherbellyachin
Sep 15, 2014 - 04:50pm PT
a source, chief?

sure,

http://www.weather.com/news/science/environment/august-2014-hottest-history-20140915

you could have done that yourself in a half a second search, chief
Bruce Kay

Gym climber
BC
Sep 15, 2014 - 05:57pm PT
First of all, GISS's US temps do NOT jive one bit with NOAA's for the month of August 2014.

WTF is up with that??

I'll tell you watts up withthat. You're a fuking moron thats what.

Has that ever occured to you? Its pretty obvious to everyone else so I just thought I'd ask in case it has never crossed your mind

rick sumner

Trad climber
reno, nevada/ wasilla alaska
Sep 15, 2014 - 06:51pm PT
Ya got a touch of heat stroke Brucie. Crawl back Into your bottle for refuge from the end of the world . I don't know what will get you first; a slow roast in the coming Venutian hell, or frostbite and asphixiation under the advancing glaciers, but surely the end is near because the "industry professional authorities" told you so as they pick your pockets.

Long live The Chief! He is a brilliant and relentness warrior for the truth.

Great post TGT. Short, sweet, highly accurate summation of the state of climate hysteria afflicting our criminal AGW industry/government complex and the dim wits that actually eat this shet up.
Sketch

Trad climber
Not FortMental
Sep 15, 2014 - 07:07pm PT
Google search for:

This past August was the warmest since records began in 1881

15,000,000 hits - Yee Haw! Boy Howdy! It's gettin' hotter.

Google search for:

Antarctica record sea ice extent

2,170,000 hits - Ho hum.... yawn.

The warmists have been quite desperate for news supporting their gloom and doom future.

Finally, some "good" news.
bobinc

Trad climber
Portland, Or
Sep 15, 2014 - 07:20pm PT
Wish it were truly 'good news'. Have any of you intellectuals actually read what 'extent' means in this context? For example, what is happening to the continental ice volume as part of the increase in sea ice extent?

Didnt think so. That would require too much effort.
TGT

Social climber
So Cal
Sep 15, 2014 - 07:42pm PT

^^^^^^^^^^^

uh,read the article!

The sea ice is formed from freezing sea water, as in, you know, really, really cold water?

has little to do with the continental ice.

http://www.thepiratescove.us/2014/09/15/if-all-you-see-1253/

sandstone conglomerate

climber
sharon conglomerate central
Sep 15, 2014 - 07:45pm PT
tits and an out-of-focus landscape?
The Chief

climber
Laughing at all you angry blinded asshat Sheep
Sep 15, 2014 - 08:15pm PT
Now for the rest of the story...


The GISS map that Norton is speaking encompasses Land & Oceans.



Here is the Land temps ONLY and tells a completely different story which as the media indicates, has NOT been published.


Slight twist of hand on the part of NASA/GISS and Nortons source, the Weather Channel.

If one takes only the Surface Temps alone, IT IS NOT THE HOTTEST August on record going back to 1881.

Here is the map that the weather channel is publishing that includes Land and Ocean Temps:



The actual GISS Land and Oceans Temps MAP for August 2014:





And here is Surface Temps ONLY for August, 2014:

http://data.giss.nasa.gov/tmp/gistemp/NMAPS/tmp_GHCN_GISS_1200km_Anom08_2014_2014_1951_1980/nmaps.gif


And the above correlates with what NOAA/NCDC show on their monthly US Temps.






Again, if Thursdays NCDC monthly State of the Climate Report does not correlate with today's GISS report, just going to show how NASA is in this for the long run and is tweeking their data.

Even more IRONIC, Land and Ocean Temps combination in order to indicate the above map L-OTI, did not begin on an official basis with GISS till 1999 when Hansen modified the process to include the SST's measured by sat's while at GISS.


So IN REALITY, this "Land and Ocean Combo RECORD" only goes back till 1950 when the base period was established ..

(We use the SST data of Reynolds and Smith [1994] for the period 1982 to present. This is their “blended” analysis product, based on satellite measurements calibrated with the help of thousands of ship and buoy measurements. For the period 1950-1981 we use the SST data of Smith
et al. [1996], which are based on fitting ship measurements to empirical orthogonal functions (EOFs) developed for the period of satellite data
)
http://pubs.giss.nasa.gov/docs/1999/1999_Hansen_etal_1.pdf

and NOT 1881.

Gotta love the NASA/GISS propaganda machine and how it feeds them sheep.


Nothing like the twisting the truth, huh GISS.





BTW, WHO AUDITS THE GISS AND NOAA on a regular basis for their work, process and integrity of information that is published and released to the public?????


Answer.... THEMSELVES!


Now if that isn't the Good old Boys Club ensuring their job security. Then I don't know what it is.






Let compare GISS LOTI maps for August 2014 back to August 1881 after of course the process was implemented by Hansen and GISS back in 1999:







August 1936:




August 1900:





August 1881:




The amount of reporting data increases with the addition of thousands of more stations AND Sat data through the modern date. Especially since the 1950's to current the date. Dah.

Lots of Gray in 1881 and just about none in 2014.

Much of that missing GRAY area encompasses both all of Antarctica and the, Arctic, Siberia, the equatorial regions along with 2/3rds of the entire continent of Africa and 1/2 of South America where warm temps are pretty constant year round.

And the accuracy of the instruments and record keeping through 1930's in the majority of the regions like the USSR, China, Africa, India etc. Well. That is another story.


Another example of the propaganda machine manipulating the truth.
Ed Hartouni

Trad climber
Livermore, CA
Sep 15, 2014 - 08:46pm PT
The Chief refers to the article:
Meehl, Gerald A., Haiyan Teng, and Julie M. Arblaster, “Climate model simulations of the observed early-2000s hiatus of global warming,” Nature Climate Change (2014), doi:10.1038/nclimate2357

which he understands only from the blog he reblogged from... The Chief did not read the paper. He might have read the abstract from that blog, I'll post it here (sorry for the cut-and-paste):

The slowdown in the rate of global warming in the early 2000s is not evident in the multi-model ensemble average of traditional climate change projection simulations1. However, a number of individual ensemble members from that set of models successfully simulate the early-2000s hiatus when naturally-occurring climate variability involving the Interdecadal Pacific Oscillation (IPO) coincided, by chance, with the observed negative phase of the IPO that contributed to the early-2000s hiatus. If the recent methodology of initialized decadal climate prediction could have been applied in the mid-1990s using the Coupled Model Intercomparison Project Phase 5 multi-models, both the negative phase of the IPO in the early 2000s as well as the hiatus could have been simulated, with the multi-model average performing better than most of the individual models. The loss of predictive skill for six initial years before the mid-1990s points to the need for consistent hindcast skill to establish reliability of an operational decadal climate prediction system.


while this is paper is new, one wonders what reference 1 is, the evidence that the observations depart from the model "ensemble."

Interestingly, that reference is:

References
1. Kirtman, B. et al. in IPCC Climate Change 2013: The Physical Science Basis
(eds Stocker, T. F. et al.) 9531028 (Cambridge Univ. Press, 2013).

The AR5 IPCC report from Working Group 1... and the date is 2013.... so a year ago (though there were advanced copies and drafts available).

What this reference is to is a "box" which is a sort of side comment of the report in the Model section (chapter 9). I'll reproduce it here.


Box 9.2: Climate Models and the Hiatus in Global-Mean Surface Warming of the Past 15 Years

The observed global-mean surface temperature (GMST) has shown a much smaller increasing linear trend over the past 15 years than over the past 30 to 60 years (Section 2.4.3, Figure 2.20, Table 2.7; Figure 9.8; Box 9.2 Box 9.2 Figure 1a,c). Depending on the observational data set, the GMST trend over 1998–2012 is estimated to be around one-third to one-half of the trend over 1951–2012 (Section 2.4.3, Table 2.7; Box 9.2 Figure 1a,c). For example, in HadCRUT4 the trend is 0.04 ºC per decade over 1998–2012, compared to 0.11 ºC per decade over 1951–2012. The reduction in observed GMST trend is most marked in Northern-Hemisphere winter (Section 2.4.3, (Cohen et al., 2012)). Even with this “hiatus” in GMST trend, the decade of the 2000s has been the warmest in the instrumental record of GMST (Section 2.4.3, Figure 2.19). Nevertheless, the occurrence of the hiatus in GMST trend during the past 15 years raises the two related questions of what has caused it and whether climate models are able to reproduce it.

Figure 9.8 demonstrates that 15-year-long hiatus periods are common in both the observed and CMIP5 historical GMST time series (see also Section 2.4.3, Figure 2.20; (Easterling and Wehner, 2009), (Liebmann et al., 2010)).. However, an analysis of the full suite of CMIP5 historical simulations (augmented for the period 2006–2012 by RCP4.5 simulations, Section 9.3.2) reveals that 111 out of 114 realisations show a GMST trend over 1998–2012 that is higher than the entire HadCRUT4 trend ensemble (Box 9.2 Figure 1a; CMIP5 ensemble-mean trend is 0.21 ºC per decade). This difference between simulated and observed trends could be caused by some combination of (a) internal climate variability, (b) missing or incorrect radiative forcing, and (c) model response error. These potential sources of the difference, which are not mutually exclusive, are assessed below, as is the cause of the observed GMST trend hiatus.

(a) Internal Climate Variability

Hiatus periods of 10–15 years can arise as a manifestation of internal decadal climate variability, which sometimes enhances and sometimes counteracts the long-term externally forced trend. Internal variability thus diminishes the relevance of trends over periods as short as 10–15 years for long-term climate change (Box 2.2, Section 2.4.3). Furthermore, the timing of internal decadal climate variability is not expected to be matched by the CMIP5 historical simulations, owing to the predictability horizon of at most 10–20 years (Section 11.2.2; CMIP5 historical simulations are typically started around nominally 1850 from a control run). However, climate models exhibit individual decades of GMST trend hiatus even during a prolonged phase of energy uptake of the climate system (e.g., Figure 9.8, (Easterling and Wehner, 2009; Knight et al., 2009)), in which case the energy budget would be balanced by increasing subsurface-ocean heat uptake (Meehl et al., 2011; Guemas et al., 2013; Meehl et al., 2013a).

Owing to sampling limitations, it is uncertain whether an increase in the rate of subsurface-ocean heat uptake occurred during the past 15 years (Section 3.2.4). However, it is very likely 2 that the climate system, including the ocean below 700 m depth, has continued to accumulate energy over the period 1998–2010 (Section 3.2.4, Box 3.1). Consistent with this energy accumulation, global-mean sea level has continued to rise during 1998–2012, at a rate only slightly and insignificantly lower than during 1993–2012 (Section 3.7). The consistency between observed heat-content and sea-level changes yields high confidence in the assessment of continued ocean energy accumulation, which is in turn consistent with the positive radiative imbalance of the climate system (Section 8.5.1; Section 13.3, Box 13.1). By contrast, there is limited evidence that the hiatus in GMST trend has been accompanied by a slower rate of increase in ocean heat content over the depth range 0–700 m, when comparing the period 2003–2010 against 1971–2010. There is low agreement on this slowdown, since three of five analyses show a slowdown in the rate of increase while the other two show the increase continuing unabated (Section 3.2.3, Figure 3.2).

During the 15-year period beginning in 1998, the ensemble of HadCRUT4 GMST trends lies below almost all model-simulated trends (Box 9.2 Figure 1a), whereas during the 15-year period ending in 1998, it lies above 93 out of 114 modelled trends ((Box 9.2 Figure 1b; HadCRUT4 ensemble-mean trend 0.26°C per decade, CMIP5 ensemble-mean trend 0.16°C per decade). Over the 62-year period 1951–2012, observed and CMIP5 ensemble-mean trend agree to within 0.02 ºC per decade (Box 9.2 Figure 1c; CMIP5 ensemble-mean trend 0.13°C per decade). There is hence very high confidence that the CMIP5 models show long-term GMST trends consistent with observations, despite the disagreement over the most recent 15-year period. Due to internal climate variability, in any given 15-year period the observed GMST trend sometimes lies near one end of a model ensemble (Box 9.2, Figure 1a,b; (Easterling and Wehner, 2009)), an effect that is pronounced in Box 9.2, Figure 1a,b since GMST was influenced by a very strong El Niño event in 1998.

Unlike the CMIP5 historical simulations referred to above, some CMIP5 predictions were initialised from the observed climate state during the late 1990s and the early 21st century (Section 11.1, Box 11.1; Section 11.2). There is medium evidence that these initialised predictions show a GMST lower by about 0.05–0.1 ºC compared to the historical (uninitialised) simulations and maintain this lower GMST during the first few years of the simulation (Section 11.2.3.4, Figure 11.3 top left; (Doblas-Reyes et al., 2013; Guemas et al., 2013)). In some initialised models this lower GMST occurs in part because they correctly simulate a shift, around 2000, from a positive to a negative phase of the Interdecadal Pacific Oscillation (IPO, Box 2.5; e.g., (Meehl and Teng, 2012; Meehl et al., 2013a)). However, the improvement of this phasing of the IPO through initialisation is not universal across the CMIP5 predictions (cf. Section 11.2.3.4). Moreover, while part of the GMST reduction through initialisation indeed results from initialising at the correct phase of internal variability, another part may result from correcting a model bias that was caused by incorrect past forcing or incorrect model response to past forcing, especially in the ocean. The relative magnitudes of these effects are at present unknown (Meehl and Teng, 2012); moreover, the quality of a forecasting system cannot be evaluated from a single prediction (here, a ten year prediction within the period 1998–2012; Section 11.2.3). Overall, there is medium confidence that initialisation leads to simulations of GMST during 1998–2012 that are more consistent with the observed trend hiatus than are the uninitialised CMIP5 historical simulations, and that the hiatus is in part a consequence of internal variability that is predictable on the multiyear timescale.

(b) Radiative Forcing

On decadal to interdecadal timescales and under continually increasing effective radiative forcing (ERF), the forced component of the GMST trend responds to the ERF trend relatively rapidly and almost linearly (medium confidence, e.g., (Gregory and Forster, 2008; Held et al., 2010; Forster et al., 2013)). The expected forced-response GMST trend is related to the ERF trend by a factor that has been estimated for the 1% per year CO₂ increases in the CMIP5 ensemble as 2.0 ± 0.7 W m⁻² °C⁻¹ (90% uncertainty range; (Forster et al., 2013)). Hence, an ERF trend can be approximately converted to a forced-response GMST trend, permitting an assessment of how much of the change in the GMST trends shown in Box 9.2 Figure 1 is due to a change in ERF trend.

The AR5 best-estimate ERF trend over 1998–2011 is 0.23 ± 0.11 W m⁻² per decade (90% uncertainty range), which is substantially lower than the trend over 1984–1998 (0.34 ± 0.10 W m⁻² per decade; note that there was a strong volcanic eruption in 1982) and the trend over 1951–2011 (0.30 ± 0.10 W m⁻² per decade; Box 9.2, Figure 1d–f; numbers based on Section 8.5.2, Figure 8.18; the end year 2011 is chosen because data availability is more limited than for GMST). The resulting forced-response GMST trend would approximately be 0.13 [0.06 to 0.31] °C per decade, 0.19 [0.10 to 0.40] °C per decade, and 0.17 [0.08 to 0.36] °C per decade for the periods 1998–2011, 1984–1998, and 1951–2011, respectively (the uncertainty ranges assume that the range of the conversion factor to GMST trend and the range of ERF trend itself are independent). The AR5 best-estimate ERF forcing trend difference between 1998–2011 and 1951–2011 thus might explain about one-half (0.04°C per decade) of the observed GMST trend difference between these periods (0.06 to 0.08°C per decade, depending on observational data set).

The reduction in AR5 best-estimate ERF trend over 1998–2011 compared to both 1984–1998 and 1951–2011 is mostly due to decreasing trends in the natural forcings,–0.14 ± 0.10 W m⁻² per decade over 1998–2011 compared to 0.0 ± 0.01 W m⁻² per decade over 1951–2011 (Section 8.5.2, Figure 8.19). Solar forcing went from a relative maximum in 2000 to a relative minimum in 2009, with a peak-to-peak difference of around 0.15 W m⁻² and a linear trend over 1998–2011 of around –0.10 W m⁻² per decade (cf. Section 10.3.1, Box 10.2). Furthermore, a series of small volcanic eruptions has increased the observed stratospheric aerosol loading after 2000, leading to an additional negative ERF linear-trend contribution of around –0.04 W m⁻² per decade over 1998–2011 (cf. Section 8.4.2.2, Section 8.5.2). (Section 8.5.2, Figure 8.19; Box 9.2 Figure 1d,f). By contrast, satellite-derived estimates of tropospheric aerosol optical depth (AOD) suggests little overall trend in global-mean AOD over the last 10 years, implying little change in ERF due to aerosol-radiative interaction (low confidence because of low confidence in AOD trend itself, Section 2.2.3; Section 8.5.1, Table 8.6, Table 8.7; (Murphy, 2013)). Moreover, because there is only low confidence in estimates of ERF due to aerosol-cloud interaction (Section 8.5.1, Table 8.6), there is likewise low confidence in its trend over the last 15 years.

For the periods 1984–1998 and 1951–2011, the CMIP5 ensemble-mean ERF trend deviates from the AR5 best-estimate ERF trend by only 0.01 W m⁻² per decade (Box 9.2 Figure 1e,f). After 1998, however, some contributions to a decreasing ERF trend are missing in the CMIP5 models, such as the increasing stratospheric aerosol loading after 2000 and the unusually low solar minimum in 2009. Nonetheless, over 1998–2011 the CMIP5 ensemble-mean ERF trend is lower than the AR5 best-estimate ERF trend by 0.05 W m⁻² per decade (Box 9.2 Figure 1d). Furthermore, global-mean AOD in the CMIP5 models shows little trend over 1998–2012, similar to the observations (Figure 9.29). Although the forcing uncertainties are substantial, there are no apparent incorrect or missing global-mean forcings in the CMIP5 models over the last 15 years that could explain the model–observations difference during the warming hiatus.

(c) Model Response Error

The discrepancy between simulated and observed GMST trends during 1998–2012 could be explained in part by a tendency for some CMIP5 models to simulate stronger warming in response to increases in greenhouse-gas concentration than is consistent with observations (Section 10.3.1.1.3, Figure 10.4). Averaged over the ensembles of models assessed in Section 10.3.1.1.3, the best-estimate greenhouse-gas (GHG) and other anthropogenic (OA) scaling factors are less than one (though not significantly so, Figure 10.4), indicating that the model-mean GHG and OA responses should be scaled down to best match observations. This finding provides evidence that some CMIP5 models show a larger response to greenhouse gases and other anthropogenic factors (dominated by the effects of aerosols) than the real world (medium confidence). As a consequence, it is argued in Chapter 11 that near-term model projections of GMST increase should be scaled down by about 10% (Section 11.3.6.3). This downward scaling is, however, not sufficient to explain the model-mean overestimate of GMST trend over the hiatus period.

Another possible source of model error is the poor representation of water vapour in the upper atmosphere (Section 9.4.1.2). It has been suggested that a reduction in stratospheric water vapour after 2000 caused a reduction in downward longwave radiation and hence a surface-cooling contribution (Solomon et al., 2010), possibly missed by the models, However, this effect is assessed here to be small, because there was a recovery in stratospheric water vapour after 2005 (Section 2.2.2.1, Figure 2.5).

In summary, the observed recent warming hiatus, defined as the reduction in GMST trend during 1998–2012 as compared to the trend during 1951–2012, is attributable in roughly equal measure to a cooling contribution from internal variability and a reduced trend in external forcing (expert judgment, medium confidence). The forcing trend reduction is primarily due to a negative forcing trend from both volcanic eruptions and the downward phase of the solar cycle. However, there is low confidence in quantifying the role of forcing trend in causing the hiatus, because of uncertainty in the magnitude of the volcanic forcing trend and low confidence in the aerosol forcing trend.

Almost all CMIP5 historical simulations do not reproduce the observed recent warming hiatus. There is medium confidence that the GMST trend difference between models and observations during 1998–2012 is to a substantial degree caused by internal variability, with possible contributions from forcing error and some CMIP5 models overestimating the response to increasing greenhouse-gas forcing. The CMIP5 model trend in effective radiative forcing (ERF) shows no apparent bias against the AR5 best estimate over 1998–2012. However, confidence in this assessment of CMIP5 ERF trend is low, primarily because of the uncertainties in model aerosol forcing and processes, which through spatial heterogeneity might well cause an undetected global-mean ERF trend error even in the absence of a trend in the global-mean aerosol loading.

The causes of both the observed GMST trend hiatus and of the model–observation GMST trend difference during 1998–2012 imply that, barring a major volcanic eruption, most 15-year GMST trends in the near-term future will be larger than during 1998–2012 (high confidence; see 11.3.6.3. for a full assessment of near-term projections of GMST). The reasons for this implication are fourfold: first, anthropogenic greenhouse-gas concentrations are expected to rise further in all RCP scenarios; second, anthropogenic aerosol concentration is expected to decline in all RCP scenarios, and so is the resulting cooling effect; third, the trend in solar forcing is expected to be larger over most near-term 15–year periods than over 1998–2012 (medium confidence), because 1998–2012 contained the full downward phase of the solar cycle; and fourth, it is more likely than not that internal climate variability in the near-term will enhance and not counteract the surface warming expected to arise from the increasing anthropogenic forcing.

Credit: WGIAR5 IPCC
Box 9.2, Figure 1: Top: Observed and simulated GMST trends in ºC per decade, over the periods 1998–2012 (a), 1984–1998 (b), and 1951–2012 (c). For the observations, 100 realisations of the HadCRUT4 ensemble are shown (red, hatched; (Morice et al., 2012)). The uncertainty displayed by the ensemble width is that of the statistical construction of the global average only, in contrast to the trend uncertainties quoted in Section 2.4.3, which include an estimate of internal climate variability. Here, by contrast, internal variability is characterised through the width of the model ensemble. For the models, all 114 available CMIP5 historical realisations are shown, extended after 2005 with the RCP4.5 scenario and through 2012 (grey, shaded; after (Fyfe et al., 2010)). Bottom: Trends in effective radiative forcing (ERF, in W m⁻² per decade) over the periods 1998–2011 (d), 1984–1998 (e), and 1951–2011 (f). The figure shows AR5 best-estimate ERF trends (red, hatched; Section 8.5.2, Figure 8.18) and CMIP5 ERF (grey, shaded; from (Forster et al., 2013)). Black lines are smoothed versions of the histograms. Each histogram is normalised so that its area sums up to one.

In this Report, the following terms have been used to indicate the assessed likelihood of an outcome or a result:Virtually certain 99-100% probability, Very likely 90-100%, Likely 66-100%, About as likely as not 33-66%, Unlikely 0-33%, Very unlikely 0-10%, Exceptionally unlikely 0-1%. Additional terms (Extremely likely: 95–100%, More likely than not >50–100%, and Extremely unlikely 0–5%) may also be used when appropriate. Assessed likelihood is typeset in italics, e.g., very likely (see Section 1.4 and Box TS.1 for more details).

Bruce Kay

Gym climber
BC
Sep 15, 2014 - 08:50pm PT
BTW, WHO AUDITS THE GISS AND NOAA on a regular basis for their work, process and integrity of information that is published and released to the public?????


you do, which is why Red state america is so freaking stupid. Or perhaps you'd prefer some overbearin' arm of Gubmint doing it?
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