UAH global temperature anomaly, a bit cooler in April

Actually April is NOT the warmest month in recorded history, well that is only if you selectively IGNORE the Vostok Ice Core Data record.
If I’m not mistaken the Vostok Ice Core Data is part of the RECORDED HISTORY and shows warmer temperatures have occurred a number of times, thus April’s not the warmest nor are the last years of recent warm temperatures… all still below the Vostok record maximums.
Anyone care to validate or refute this?

This change is clearly the start of the predicted long-term downward trend, and even at just the observed 0.15C/month, we’ll see a temperature decline over the next year of 1.8C, and, obviously, this trend in declining temperature is only likely to accelerate.

yeh, thats a proxy. not temp recording.

Eh! 0.14 degrees Celsius per decade since 1979? Ladies and Gentlemen we are doomed.
Doomed I tell yah! This is going to be the hottest year EVAAH!
Returning to something that bears even a modicum of resemblance to reality…
Whether or not we have a La Nina, it looks like temperatures are “normal”, whatever that means, I hate to make predictions but even without a La Nina I reckon a re-run of 2007 is on the cards.
Just my 2C

As a comparison to Mt. Pinatubo, why didn’t the eruption of Mt. St. Helens have any ‘noticeable’ affect on weather?

the tropics showed signs of retreating from the current El Nino event
Joe Bastardi forecast for next 9 months, till January, 2011:
El Nino ending, La Nina coming,
heavy hurricane season for U.S.,
rapid cooling in general worldwide going to negative anomaly,
another cold winter for Europe, Alaska, and Western half of Canada (looks like no warm winter for Vancouver this upcoming year, sorry global warming alarmists but the warm Olympics weren’t caused by man but by El Nino) :
5/5/10 “Sink-o” De Nino… The Rapid Collapse of El Nino
4:34 minute video
http://www.accuweather.com/video/83060117001/sink-o-de-nino-the-rapid-collapse-of-el-nino.asp?channel=vblog_bastardi

I was looking at the UAH ch05 graph Roy. Why the arbitrarily chop off of data mid 1998? It would be nice to compare the day to day temps of 2010 el nino with that of 1998 ( also in first few months of year ), but someone decided not to let us. Why’s that?
Also, temp anomalys…
1998 1 0.58
1998 2 0.76
1998 3 0.53
1998 4 0.76
2010 1 0.64
2010 2 0.61
2010 3 0.66
2010 4 0.50
the 20 year record high in the 1st few months of the year should be mostly composed of the 1998 peak. But when I compare the data given to the graph, it doesn’t corrispond, and in an odd way. Anyone else want to check to see what I mean?
http://vortex.nsstc.uah.edu/data/msu/t2lt/uahncdc.lt
http://discover.itsc.uah.edu/amsutemps/execute.csh?amsutemps

Somewhat on topic: NINO3.4 SST anomalies (weekly) have dropped below the threshold of an El Nino:
http://bobtisdale.blogspot.com/2010/05/nino34-sst-anomalies-in-neutral.html

Thank you for your comment Derek B.
In the Vostok Ice Core Data there are a number of periods significantly warmer than the current period by about 2c or so. I’m referring to those periods.
While the Vostok data was “written” by humans due to means of extracting ice cores and sampling them recently it is “current” history in that sense. Of course the data is from a very long period of time so it predates all of recorded human history except the discovery of fossilized bones. Really this aspect isn’t relevant.
Yes, it would be nice to learn more about the Vostok Ice Core Data, maybe one of the people more educated on ice core data would be kind enough to fill us in on the details? The precision? The history? What it teaches us about the past and about today? Future ice core projects? How important it is as a proxy? Can it have finer precision? What is it’s maximum resolution? Why is it ignored so much by the alleged climate researchers focused on CO2 nightmarish dooms-day gore scenarios?
The main point I’m attempting to make it that it is a false statement to say that “this month, this year, this decade, this century, whatever” is the warmest period on the record when clearly it’s not since the records obviously includes the Vostok Ice Core Data.
Now maybe they actually mean to say the warmest on record using thermometers or satellites or their favorite data set. If that is the case then they need to be more precise and specify what record they are using otherwise they are, ahem, making a scientifically false statement. The Vostok data proves them wrong.
Worse yet, they are allegedly climate scientists and should know their own field better than you or I.
Maybe I’m just being persnickety about this point but it really annoys me to hear that it’s the “warmest T on record” when clearly it is NOT! As a scientist one must endeavor to speak clearly about ones work and especially carefully about the positive claims one is asserting.
I’m simply asking that the “precision bar be raised” to factual by those making the wild claims of doom and destruction. Not too much to ask. Or maybe it is?
(Oh, on the prior post the grammar on my first sentence was a bit backwards. The second sentence was correctly worded though just in case anyone wondered).

I’d like to add, that I don’t think it is appropriate to say that its’ the warmest T on record when the Vostok Ice Core Data shows otherwise. Even to say it is the warmest T on record in a particular data set can be misleading since it’s made out to be doomsday.
Being misleading in science is a violation of ethics. In case you think that’s just nuts, Richard Feynman is the source of that standard of ethics in science. In Richard Feynman’s own words on scientific ethics:
“But this long history of learning how not to fool ourselves–of having utter scientific integrity–is, I’m sorry to say, something that we haven’t specifically included in any particular course that I know of. We just hope you’ve caught on by osmosis.
The first principle is that you must not fool yourself–and you are the easiest person to fool. So you have to be very careful about that. After you’ve not fooled yourself, it’s easy not to fool other scientists. You just have to be honest in a conventional way after that.
I would like to add something that’s not essential to the science, but something I kind of believe, which is that you should not fool the layman when you’re talking as a scientist. I am not trying to tell you what to do about cheating on your wife, or fooling your girlfriend, or something like that, when you’re not trying to be a scientist, but just trying to be an ordinary human being. We’ll leave those problems up to you and your rabbi. I’m talking about a specific, extra type of integrity that is not lying, but bending over backwards to show how you are maybe wrong, that you ought to have when acting as a scientist. And this is our responsibility as scientists, certainly to other scientists, and I think to laymen.
For example, I was a little surprised when I was talking to a friend who was going to go on the radio. He does work on cosmology and astronomy, and he wondered how he would explain what the applications of this work were. “Well,” I said, “there aren’t any.” He said, “Yes, but then we won’t get support for more research of this kind.” I think that’s kind of dishonest. If you’re representing yourself as a scientist, then you should explain to the layman what you’re doing–and if they don’t want to support you under those circumstances, then that’s their decision.
One example of the principle is this: If you’ve made up your mind to test a theory, or you want to explain some idea, you should always decide to publish it whichever way it comes out. If we only publish results of a certain kind, we can make the argument look good. We must publish both kinds of results.
I say that’s also important in giving certain types of government advice. Supposing a senator asked you for advice about whether drilling a hole should be done in his state; and you decide it would be better in some other state. If you don’t publish such a result, it seems to me you’re not giving scientific advice. You’re being used. If your answer happens to come out in the direction the government or the politicians like, they can use it as an argument in their favor; if it comes out the other way, they don’t publish it at all. That’s not giving scientific advice. ”
http://pathstoknowledge.net/2010/02/19/cargo-cult-science-a-lesson-from-richard-feynman-for-scientists-of-today-to-learn/
It sounds like some alleged climate scientists might be in violation of Richard Feynman’s standards I dare say. Their names are well known.

Andrew W says:
May 5, 2010 at 2:54 pm
This change is clearly the start of the predicted long-term downward trend, and even at just the observed 0.15C/month, we’ll see a temperature decline over the next year of 1.8C, and, obviously, this trend in declining temperature is only likely to accelerate.

Pro-AGW humour at sceptics’ expense. It has a frozen pizza quality about it. I wonder how long he’s been waiting to serve it out.

Global temperatures usually peak about 3 months after the ENSO. This El Nino peaked in mid-December so the usual pattern would have predicted that temperatures peaked in mid-March. That is what the UAH and RSS satellite temps have shown.
The El Nino, however, cooled down fairly slowly in January, February and March so temperatures will also cool down slowly in the 3 month lag fashion.
There is one wild-card here and that is the AMO. Sometime, the AMO spikes in response to an El Nino. This only seems to happen with the larger El Ninos and this one was probably big enough. Looking at the weekly SST series for the AMO region, it appears that the AMO is really spiking this time. This will further slow the cool down so it won’t be until August or so before there is a significant down-turn in global temperatures (to the 0.35C range or so, we’ll be in the 0.5 to 0.45 range until then).
If a La Nina develops (and the AMO cools down closer to normal), temperatures will decline to close to 0.2C by the end of the year.

Look, I am a geoscientist and have great respect for those who gather data about climate. But when someone tells me that 2010 is warmer than 2007, I reach cognitive dissonance.
Quite simply, I can’t trust these numbers anymore and I will ignore them.

I do not believe for a second that March was the warmest in history. Both Siberia and Britain reported record cold. China reported colder than normal weather. Antarctica experienced record cold. The arctic circle experienced a normal ice extent, with particularly cold weather in the Baltic. Norway was slightly warmer than normal. Barely measurable. Australia and Canada reported warm weather. The former easily match the latter for area. The map heat areas seem to be most prevalent where there are no thermometers.

It’s 8 degrees cooler than it was 2.5 hours ago. No joke. My wife watches the temps hourly.

Dr. Spencer, I appreciate what you’re doing. But, likely, like many here, I’ve got some questions. I could and have (in some cases) looked it up myself, but I prefer to hear it “from the horses mouth” as it were. What exactly are you measuring? Are you really measuring the earth’s surface? What technology is employed? Do clouds interfere? Is there an algorithm in place to adequately account for interference? In other words, I’m woefully ignorant of your work. Mercury thermometers, I got that. Your work, I need to know more about it before it can be embraced as knowledge.

David L says:
May 5, 2010 at 7:01 pm
It’s 8 degrees cooler than it was 2.5 hours ago. No joke. My wife watches the temps hourly.
See, proof positive of climate change!!!! If you buy big Al’s absolution credits, you’ll be ok!!!! And then, problem solved, and you can then claim virtue over the less pious polluters!!!!

@MattN
I agree. After all, El Nino (Modoki is loosing momentum with April lower than March. And look, each month of June to August 1998 was higher compared to April 2010.

R. Gates:
All the heat is coming from the Australian Governments department of Hot Air, otherwise known as the Australian Climate Change Regulatory Authority, which will be doing absolutely nothing for the next 3 years despite having over 400 staff.
As for the temps: I don’t particularly care if it’s the warmest year on record; alarmists are still yet to conclusively prove by empirical evidence that significant warming is caused by humans, and not by Nature (and I don’t mean the magazine).
I wouldn’t be surprised however, if we now sink into a long downward trend as per Andrew W’s comment. I would be equally unsurprised if alarmists try and pin that on humans.

I’ll check back for answers later………calling it a night.
Peace.

la Nada!!!!! Very funny!!!!!

Four questions:
1) Where in the atmosphere does the primary physical phenomenon of the the absorption and retransmission of longwave radiation occur? Or said another way, at what layer of the atmosphere is CO2 at the highest concentration by mass where its greenhouse characteristics will exhibit the largest effect?
2) What percentage of the retransmitted longwave radiation will be directed into space, and what percentage is eventually directed back to the ground?
3) What should the effect of a increasing amounts of longwave absorbing CO2 in the troposphere have on the stratosphere?
4) Isn’t it healthy that someone get on a primarily AGW skeptics site and act as a skeptic about the skeptics? Otherwise, wouldn’t the skeptics just keep agreeing with each other like bobble-headed dolls looking at their own reflection in the mirror?
And a final comment: It’s very hard to discount this graph of sunspot number and global temps:
http://www.climate4you.com/Sun.htm#Global temperature and sunspot number
I’ve studied it, and the data that goes along with it for a long time, as I’m sure many of you have. The effect of the long and deep solar minimum is obvious, as is the effect of this past and now waning El Nino, but even if we get a weak solar maximum, as is predicted and if we get another El Nino, say in late 2011 or 2012, it’s hard not to imagine we’ll see some more instrument record global temps. Why is it so difficult for AGW skeptics to accept the basic physical greenhouse effects of increasing amounts CO2?

But it avoids the micro- and mesosite issues with ground sensors. And there’s near-full coverage. It’s probably the best measure available.
But, as a downside, if the instruments drift then there is absolutely no way of picking that up. The whole upward trend could easily be an artifact, and we have no way of knowing.
I would actually have more confidence if they were calibrated to direct earth (or atmospheric) measurements once in a while.

In the UAH plot on top og the page there are 2 dips downwards before the so called Mt. Pinatubo Cooling.
-approx 1982
-approx 1985
The 85 dip is lower than the Pinatubo dip.Anyone knows what caused these 2 dips?

@R. Gates May 5, 2010 at 9:53 pm
“Why is it so difficult for AGW skeptics to accept the basic physical greenhouse effects of increasing amounts CO2?”
Not difficult at all. I fully accept that CO2 has a greenhouse effect – much less than H2O though.
Increasing CO2 levels will (everything else being equal) lead to a very trivial and beneficial increase in temperatures and will also promote plant growth.
But human CO2 emissions are NOT a problem. Forget tendentious and incompetent computer models and face up to the real world.

Mr. Gates how come the earth didn’t get cooked when C02 was upto 20 times higher? Also C02 effect is logarithmic right, have you factoured that in? Also is not a rise in C02 a good thing? Seems we were getting somewhat short. Over history C02 is in decline and at 150 ppm plants will get stressed, then there goes my morning orange juice. Now if fossil fuels are contributing to the rise in C02 and if this rise is having a warming effect, what happens when we either run out or quit burning fossil fuels?

R.Gates: You ask, “Why is it so difficult for AGW skeptics to accept the basic physical greenhouse effects of increasing amounts CO2?”
For me, the answer is that to accept a greenhouse effect from CO2 violates the fundamentals of process control. Engineers world-wide laugh at the concept of CO2 and greenhouse gas effect. see the most widely-read page on my blog at –
http://sowellslawblog.blogspot.com/2009/02/chemical-engineer-takes-on-global.html
and its companion post at
http://sowellslawblog.blogspot.com/2010/03/chemical-engineer-slams-global-warming.html
When the climate science is consistent with process control, then you will have something worth discussing. Climate scientists have a very long way to go on that.
Also, until AGW proponents take proper account of albedo, especially due to clouds, their science is doomed to failure. Same for heat released in the higher altitudes from rain storms. Same for wind and its effects on temperature measurements. Dust in the wind also has major effects, yet is not a part of any model I have heard of.
Finally, the entire historical temperature record is corrupt, as Chiefio has shown in marvelous detail. My own feeble efforts showed that hadCRUT3 published data for the USA lower 48 states has essentially zero warming. What little warming appears there is easily explained by population growth and Urban Heat Island effects. (see sowellslawblog and hadCRUT3 temperatures)

R. Gates says:
May 5, 2010 at 9:53 pm
The reason we don’t accept the basic physical greenhouse stuff is that we don’t actually live in one!

R. Gates wrote: “Why is it so difficult for AGW skeptics to accept the basic physical greenhouse effects of increasing amounts CO2?”
And why is it so difficult for AGW proponents to accept the fact that ENSO and global TLT is not linear?
http://bobtisdale.blogspot.com/2009/06/rss-msu-tlt-time-latitude-plots.html
BTW: The long term TSI reconstruction in your solar link is outdated.

R. Gates: The solar minimum is over, and unless we see some major volcanic activtiy (hundreds of times larger than what we’ve seen in Iceland so far) than the next few years are going to be warmer. The small drop from March to April could very well be from the fading El Nino, but with the solar max ahead of us, we’ve got warming ahead over the next few years as well…
I really hope you’re right, nothing would be better than having warming ahead of us for the next few years. But unfortunately I don’t think you’re a psychic, so there’s still a possibility that we have some years of cooling ahead of us.

Roger Sowell says:
May 5, 2010 at 11:49 pm
Finally, the entire historical temperature record is corrupt, as Chiefio has shown in marvelous detail. My own feeble efforts showed that hadCRUT3 published data for the USA lower 48 states has essentially zero warming. What little warming appears there is easily explained by population growth and Urban Heat Island effects. (see sowellslawblog and hadCRUT3 temperatures)
The UAH record shows that the USA lower 48 states has warmed at the rate of 0.21 deg per decade since 1979. Perhaps the warming cannot be “easily explained by population growth and Urban Heat”.

R. Gates says:
May 5, 2010 at 9:53 pm
Why is it so difficult for AGW skeptics to accept the basic physical greenhouse effects of increasing amounts CO2?
Because
1. The increase in CO2 LAGS that of temperature and CO2 is LESS soluble in water at higher temperatures.
2. Seventy percent of the earth is WATER therefore the solubility of CO2 in H2O just might explain the increase.
3. WATER is the more abundant and much more variable and powerful green house gas AND it overlaps the CO2 absorption bands.
4. Plants tell us there was a lot more CO2 on earth and we are presently in a CO2 starved time. (THAT was the real crisis)
5. The IR absorption is logarithmic in regards to concentration. A look at the spectra shows there just isn’t very much more energy to be absorbed by CO2 so we are at the point of diminishing returns in spades.
6. Climate is very complex we are kidding ourselves if we think we completely understand all the factors that control it. CO2 is just one of many factors and a minor one at that. WATER is a more likely candidate for a major player.
And last but not least do not forget the politics involved or the data
Skeptics do not deny greenhouse gases we just do not think CO2 is the monster under the bed.

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John Finn says:
May 6, 2010 at 3:02 am
Roger Sowell says:
May 5, 2010 at 11:49 pm
Finally, the entire historical temperature record is corrupt, as Chiefio has shown in marvelous detail. My own feeble efforts showed that hadCRUT3 published data for the USA lower 48 states has essentially zero warming. What little warming appears there is easily explained by population growth and Urban Heat Island effects. (see sowellslawblog and hadCRUT3 temperatures)
The UAH record shows that the USA lower 48 states has warmed at the rate of 0.21 deg per decade since 1979. Perhaps the warming cannot be “easily explained by population growth and Urban Heat”.
________________________________________________________________________
I think Roger Sowell was talking about this:
US temp graphs.

R. Gates
It is very well known that the lower troposphere temperatures lag ENSO by approx 6-7 months. So if El Nino is just now beginning to fade, we can expect lower troposphere temps to fade in around 6-7 months.
So, if the recent El Nino peaked around Feb 2010, then we would expect the corresponding lower troposphere temperatures to peak around August 2010 (other factors, e.g. volcanic activity, notwithstanding).
I’m surprised you aren’t aware of this. I thought it was pretty common knowledge (although I’m also surprised nobody else has pointed it out)

R Gates
Why is it so difficult for AGW skeptics to accept the basic physical greenhouse effects of increasing amounts CO2?>>
I accept them. But AGW relies on a linear extrapolation of their effects combined with a linear extrapolation of increasing acceleration of fossil fuel consumption, ignores cooling effects, and assumes that the effects are dominant over natural processes.
The facts are the CO2 has a diminishing effect as concentration rises, the planet must radiate heat to space and this increases exponentially with temperature, itz not possible to increasingly accelerate fossil fuel consumption, and the variability of natural processes appear to be so large in comparison to CO2 as to render it a rounding error. Everything I see from the AGW camp is misdirection and obfuscation designed to divert attention from these facts. And BTW, your comment about skeptics all agreeing with one another? sorry, but the best threads on this site frequently feature skeptic camps ripping each other’s heads off over science, and that is how it should be… and is.

Caleb says:
May 6, 2010 at 6:35 am
I comment here fairly often, but never get even 10% the number of replies that Mr. R Gates gets.
I’m wicked jealous.
That’s because you speak the common sense of observations.

“UAH Global Temperature Anomaly, A Bit Cooler In April”
Does anyone else have the feeling that if we had UAH Global Temp Anomaly Data for the past 10,000 years that the comments would be ‘nearly’ the same? Watching interglacial temperature chart changes each month is like watching paint dry. I’m now fairly convinced that our species does not think well when the temp is warm. I don’t think CO2 or the flatulance of cows, pigs, birds, or people has anything to do with it. But factories and volcanoes, now that’s a different can of worms.

R. Gates: The solar minimum is over, and unless we see some major volcanic activtiy (hundreds of times larger than what we’ve seen in Iceland so far) than the next few years are going to be warmer. The small drop from March to April could very well be from the fading El Nino, but with the solar max ahead of us, we’ve got warming ahead over the next few years as well…
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Isn’t that remark a thinly veiled admission of that fact that so-called ‘AGW’ is actually a fiction?
IF CO2 were really the driver of any kind of warming, then regardless the minor vagaries of the Sun and whatever volcanoes, the temperature would still have risen. That it has not puts the truth to the matter.

John Finn said:
Was he? Since when did Hansen have anything to do with HadCrut3? Also RS talks how the warming can be explained by UHI and adjustments. The “warming” has taken place since the 1970s and is evident in the satellite record as well as the surface record. My point, therefore, is still valid. Whatever the reason for the warming it does not appear to be related to either of the factors cited by Roger Sowell.
I suggest you read his post again.
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Satellite measurements which reenforce questionable Earth-based measurements are valid for one purpose only: They confirm the fact that a bias in measurement was made.
Since in almost all cases the preferred location of referenced sensors happens to be in large urban areas, with little if any being used in the rural areas, then using a satellite to confirm the error and calling it good is the height of intellectual dishonesty.
Further, if the satellite measurements for areas OUTSIDE the UHI areas are not included in a complete assessment of an entire land mass, then for all intents an purposes the record is specious in and of itself and is invalid save to demonstrate how to construct an entirely dishonest assessment.
The quintessence of this matter is one placing a drop of sewage into a bottle of fine wine: The net result is that you’ve a bottle of sewage.

The point of my earlier comment was that the warming, if any, may be man-made but not by CO2. Chiefio shows biased temperature records due to deliberate selection of thermometers over time, and I show the slight warming from the hadCRUT3 data is due to urban heat island effects. Of the 86 cities in the US with temperature records from hadCRUT3, very few show any warming at all. See Abilene, Texas for example. Some show an overall cooling. Some show a dramatic recent cooling, with the most pronounced being Eureka, California.
The satellite measurements, the topic of this post, are interesting but of too short duration for anything other than saying “hey, that’s interesting.” With no disrespect to Dr. Spencer, indeed, I applaud much of his work, what Dr. Spencer and others who monitor and report on the satellite data likely are measuring is not the result of increases in CO2, but a mix of factors such as I described in part above: clouds and albedo, etc.
CO2 is innocent as an agent of warming, as my references to process control demonstrate. This is relevant because most climate scientists (IPCC in particular) strongly advocate controlling the earth’s temperature increase by slowing or eliminating the input of CO2 into the atmosphere caused by man’s activities: primarily fossil fuel combustion but also other so-called greenhouse gases. For any control system to work, the fundamentals of process control must be met. CO2 does not meet those requirements.
Until climate scientists reconcile process control fundamentals with their assertion that CO2 reduction will decrease earth’s global average temperature, they have no physical foundation upon which to stand. As Dr. Pierre Latour stated, it won’t work. (my paraphrase). Dr. Latour holds Professional Engineer designations in both chemical engineering and process control, a PhD in chemical engineering, and more than 40 years success implementing process control systems world-wide. Engineers world-wide pay close attention when he speaks or writes. Climate scientists would do well to do likewise.
I have spoken professionally on this topic (the process control aspect of global warming) to hundreds and hundreds of engineers over the past two years, with almost unanimous agreement among my audiences. The few dissenters are employed in government agencies. Under the prevailing conditions in those agencies, they lose their jobs if they agree.

well it may be warming slightly at 14,000ft but i don’t think it makes much difference. here is 188% snowpack and still climbing at 10,000ft.

Who let the trolls out?
And it’s always the same old same old tiresome cr#p.

R. Gates: The solar minimum is over
AGWs as usual being slippery as eels. Before the late 20th century (non-anthropogenic cyclical) warming ended, AGWers were falling over eachother to use abusive language to deride proponents of a role of the sun in climate. Now they are trying to find solace in a sputtering rise in sun-specks most of which would be undetectable over most of the history of the sunspot record.
Looking at the troposphere and at sunspots is to look in the wrong direction. If you are interested in future climate you should look below the thermocline.

Caleb says:
May 6, 2010 at 6:35 am
I comment here fairly often, but never get even 10% the number of replies that Mr. R Gates gets.
I’m wicked jealous.
On Joseph d’Aleo’s recent ENSO update I posted sarcastically “looking good for a hottest on record 2010” – meaning the precise opposite. I was mistaken for a troll and got lots of replies. R. Gates says something similar and appears – astonishingly – to be serious.

John Finn says:
May 6, 2010 at 12:55 pm – re wanting a link. You got it. Note which cities trends show a slight warming, and which of those cities showed a corresponding population growth.
http://sowellslawblog.blogspot.com/2010/02/usa-cities-hadcrut3-temperatures.html
Note also the curious effect that I call the Abilene Effect, where the appearance of global warming occurred not by hotter summers or warmer winters, but by colder winters beginning at the start of your “modern warming period” of the late 1970’s.
http://sowellslawblog.blogspot.com/2010/01/abilene-tx-not-impacted-by-global.html

899 says:
May 6, 2010 at 1:43 pm

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The earliest known temperature records are anecdotal in nature, revealing climate/weather conditions of the various periods.
Ah – anecdotal. Is that where soe one notices it’s particualrly hot, cold, dry or wet and records the fact. Are you sure we get typical conditions from anecdotal records?
It would be completely dishonest to dismiss —out of hand— the historical records recounting events of whatever period when a particular climate/weather event was mentioned.
I’m not dismissing anything. However it might be wise to treat such records with caution.
For instance, the freezing of the Thames river,…..
The Thames has been frozen on many occasions throughout history – even during the MWP. Thames freezing events are noot unique to the LIA.
…. the advance of glaciers in the Alps which decimated whole villages, the warm spells of a prior period where certain rivers ran so shallow as to afford crossing by foot, the growing of grapes in the north of England, the Norse settlement of Greenland
We grow grapes in England now. The Romans did attempt to grow grapes as far north as Hadrian’s wall which while possible would not provide ideal conditions.
A mere comparison to modern weather effects which would likely result in those instance repeating themselves, is sufficient to accurately estimate what the temperatures were in those periods. You don’t numerical data when the description of an effect more than suffices to replicate such, i.e., a pan of water still boils at a certain temperature and pressure.
About as reliable as tree-rings.
Insofar as the UHI goes, the implication of looking at only a particular span of dates to the exclusion of all others and declaring that there’s a significant change when in fact the change is —in respect to all which preceded— rather insignificant, raises the eyebrows of critical thinkers.
So, my question is this: Why not completely exclude the temperature data from any location which is thickly settled such as to influence the temperature record, and then evaluate matters from that point, instead of engaging in completely dishonest manipulations such as ‘homogenization’ in order to effect a desired result?
like the oceans, do you mean?

Said John Finn:
“Ah – anecdotal. Is that where soe one notices it’s particualrly hot, cold, dry or wet and records the fact. Are you sure we get typical conditions from anecdotal records?”
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You condescend well. Does that come with practice?
Were I to take your tack on matters, then virtually no historical record is worthy of mention, and therefore even the current instrument records are null and void, because after all they are anecdotal in the entirely scientific sense, i.e., that’s just so yesterday! That was then, and this is now …
Hell, why not toss out every history book too? Who cares what happened, because —according to yourself— the historians of yore were all a pack liars too, and given to exaggeration, right?
It is one heck of a stretch to declare that the chroniclers of old were engaging in a keen deception so in order to fool future generations whom they would never know.
That might work all except for one thing: What would they gain by deception?

Roger Sowell says:
May 6, 2010 at 2:41 pm
John Finn says:
May 6, 2010 at 12:55 pm – re wanting a link. You got it. Note which cities trends show a slight warming, and which of those cities showed a corresponding population growth.
Ok – I’m not going over each and every station you’ve plotted , so let’s try a different approach.
I acknowledge Urban Heat (UH) exists but I don’t believe it significantly influences the general trend. You, on the other hand, think it does. Since December 1978, UAH have been analysing temperature data from MSUs on board orbiting satellites. This data is not contaminated by UH. The UAH trend between 1979 and 2008 (30 years) over the 48 states is ~0.25 deg per decade. The surface (station) record trend over the same period is also ~0.25 deg per decade. Now if the surface trend includes a UH trend it means that at least part of the troposphere (satellite) warming is due to a factor which does not affect the surface and, what’s more, that warming just happens to be of the same magnitude as the urban heat warming. I think this is unlikely. I think the most likely explanation is that urban heat has very little effect on the surface trend. Furthermore, because ~70% ofthe earth’s surface is covered by oceans (no UH effect), it has even less effect on the global trend.

899 says:
May 5, 2010 at 3:48 pm
As a comparison to Mt. Pinatubo, why didn’t the eruption of Mt. St. Helens have any ‘noticeable’ affect on weather?
St. Helens was smaller, but more importantly the Helens blast was directed sideways, not up. So much less stuff was injected into the stratosphere than happened with Pinotubo.

@ John Finn, May 6, 2010 at 5:01 pm
I do hope you can find time to examine the charts I referred to above, and contemplate why CO2 failed in its assigned mission to warm so many cities in the lower 48 states. Especially the charts that show dramatic cooling for Eureka, Los Angeles, and San Diego (all in California), Washington D.C., and Marquette (Michigan).
If CO2 causes warming across the globe, how then can those cities be cooling so dramatically? And, lest your answer be that the California cities all are on the coast and cooled by the Pacific, please consider the chart for San Francisco – it shows a gradual warming, but is also on the coast, and located approximately mid-distance between Eureka and Los Angeles.

The global-average lower tropospheric temperature continues warm: +0.50 deg. C for April, 2010, although it is 0.15 deg. C cooler than last month. The linear trend since 1979 is now +0.14 deg. C per decade.
YR MON GLOBE NH SH TROPICS
2009 1 0.252 0.472 0.031 -0.065
2009 2 0.247 0.569 -0.074 -0.044
2009 3 0.191 0.326 0.056 -0.158
2009 4 0.162 0.310 0.013 0.012
2009 5 0.140 0.160 0.120 -0.057
2009 6 0.044 -0.011 0.100 0.112
2009 7 0.429 0.194 0.665 0.507
2009 8 0.242 0.229 0.254 0.407
2009 9 0.504 0.590 0.417 0.592
2009 10 0.361 0.335 0.387 0.381
2009 11 0.479 0.458 0.536 0.478
2009 12 0.283 0.350 0.215 0.500
2010 1 0.649 0.861 0.437 0.684
2010 2 0.603 0.725 0.482 0.792
2010 3 0.653 0.853 0.454 0.726
2010 4 0.501 0.796 0.207 0.634
Arctic temps (not shown) continued a 5-month string of much above normal temps (similar to Nov 05 to Mar 06) as the tropics showed signs of retreating from the current El Nino event. Antarctic temperatures were cooler than the long term average. Through the first 120 days of 1998 versus 2010, the average anomaly was +0.655 in 1998, and +0.602 in 2010. These values are within the margin of error in terms of their difference, so the recent global tropospheric warmth associated with the current El Nino has been about the same as that during the peak warmth of the 1997-98 El Nino.
As a reminder, two months ago we changed to Version 5.3 of our dataset, which accounts for the mismatch between the average seasonal cycle produced by the older MSU and the newer AMSU instruments. This affects the value of the individual monthly departures, but does not affect the year to year variations, and thus the overall trend remains the same as in Version 5.2. ALSO…we have added the NOAA-18 AMSU to the data processing in v5.3, which provides data since June of 2005. The local observation time of NOAA-18 (now close to 2 p.m., ascending node) is similar to that of NASA’s Aqua satellite (about 1:30 p.m.). The temperature anomalies listed above have changed somewhat as a result of adding NOAA-18.
[NOTE: These satellite measurements are not calibrated to surface thermometer data in any way, but instead use on-board redundant precision platinum resistance thermometers (PRTs) carried on the satellite radiometers. The PRT’s are individually calibrated in a laboratory before being installed in the instruments.]