Models(4) Iconic Figure:

By: Dr. Ricky Rood , 4:42 AM GMT on February 13, 2008

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Models(4) Iconic Figure:

Of the figures that I consider the Iconic Figures of climate, there is one based totally on models. A recent version of this figure from the IPCC 2007 is given here.



Figure 1: Observations and simulation of the past century from the IPCC 2007 Technical Summary (Working Group 1) (largish PDF).

This is a figure of, approximately, the last century. In this figure there are three traces. One of traces, the black one, is of the observed, globally averaged surface temperature record. In the bottom figure is a blue curve, which is a model simulation that does not include anthropogenic (human-related) forcing. That is, it is “natural” forcing. In the top curve there is a red curve that is a model simulation that includes both natural and anthropogenic forcing. The point of this figure is that both natural and anthropogenic forcing is important, and that the recent warming requires the inclusion of anthropogenic forcing to simulate the recent observed temperature increase.

Forcing: For the purpose of this figure, “forcing” are those things that change the ability of the Earth to absorb or reflect radiative energy. Another “forcing” is the radiative energy that comes from the Sun. “Natural” forcing starts with the variability of the Sun. Of special importance in the realm of natural forcing is the impact of volcanic eruptions. Large volcanic eruptions put aerosols into the atmosphere. Aerosols above the Earth’s surface can reflect more solar radiation or they can absorb radiation in the atmosphere. These help cool the surface of the Earth. Aerosols also impact the infrared radiation; that is, the radiation emitted by the Earth back to space. Other natural forcings include water in the atmosphere, in all phases, and carbon dioxide. In general, these model experiments assume that the amount of carbon dioxide in the atmosphere prior to, about, 1850 is “natural.” Of course, the amount of solar radiation that is reflected by the surface is also included – ice and land.

In contrast to “natural” forcing is anthropogenic or human-related forcing. This is change in the forcing relative to the natural forcing. The most important of the anthropogenic forcings is due to carbon dioxide, which is calculated as the additional forcing due to the increased amount of carbon dioxide relative to the “pre-industrial” amount of carbon dioxide. Pre-industrial forcing is linked to about the year 1850. There are other greenhouse gases like methane, nitrous oxide, and the chlorofluorocarbons. Nitrous oxide increases are largely related to use of synthetic fertilizers. Other anthropogenic changes in the radiative balance of the Earth are related to changes in reflection at the surface due to how we use land.

The Plot: Here is my description of this plot. The dark red and the dark blue lines are averages from many model simulations. The light lines that surround the dark lines are all of the individual simulations. Prior to 1950 the natural and anthropogenic simulations are not much different from each other. After 1960 only the plot with anthropogenic forcing follows the temperature observations. Perhaps more importantly, the natural and anthropogenic curves diverge from each other as time goes along.


The light lines surrounding the dark lines give some idea of model variability. It is notable that, for the most part, this variability covers the range of variability in the observations. The models do not follow, point by point, the shorter scale variability in the observations, for example between 1920 and 1930. The models have variability, such as the El Nino – La Nina and North Atlantic Oscillation. The spread of the models suggests that the model variability covers this range of variability, but the models are not tracing this variability on an event-by-event basis. The comparable spread in the models and the observations also serve as a sanity check that the models represent variability in the same range as the Earth’s climate.

The simulations do show the impact of several large volcanic eruptions. The volcanoes do cause cooling of the globe. Volcanic eruptions, and especially the well observed Mount Pinatubo eruption in 1991, provide opportunities to evaluate processes in models.

It is also of interest to examine where the models and the observations do not agree. A most interesting period is from 1935-1940, a period when the planet was warm. (Thanks to crucilandia for pointing a reference to get me started.) A substantial literature is developing that examines this period. It seems to be associated with substantial Arctic warming. It is a period that demands more study. The cooling that all of the models calculate about 1915 is also interesting.

An important take away message from these simulations is that there are factors other than carbon dioxide that cause temperature variability. Hence, carbon dioxide and temperature are not necessarily correlated on shorter scales of variability. (This is a like my wave metaphor on this blog. )


Conclusions: This is a figure open to interpretation. Personally, I find this figure compelling. I know how difficult it has been to develop the models and to specify the forcing. There is also a huge depth of analysis at different levels of detail and averaging that support the conclusion that it is only with increasing carbon dioxide forcing that the recent temperature increase can be explained.

Others can look at this plot, and come to a different conclusion. One issue that many raise is what about the treatment of aerosols? This is a process in models which has substantial uncertainty in its quantification.

Looking forward to the comments.


Here are the previous blogs on models.
Uncertainty and Types of Models
Models (1) Assumptions
Models (2) Forgotten Layers
Models (3) Predictable Arguments

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289. SteveBloom
6:03 PM PST on February 18, 2008
Re #288: That's OK, lat. Just remember that every time I see you comment I'll think of you drinking Edna. It's quite the image -- thanks for focusing it.
288. latitude25
1:55 AM GMT on February 19, 2008
You mean like apparent correlations between temp and CO2?

285. SteveBloom 1:34 AM GMT on February 19, 2008
Re #283: Based on your comments

It was your constant personal attacks and your comments that made me think of Dame Edna. She had a certain pompous, fluffy,
yet trashy way of saying things, and you remind me of her.
Thinking it is her posting, has made your posts even funnier.

In case you don't know who I'm talking about:
Link
Member Since: Posts: Comments:
287. sebastianjer
8:52 PM EST on February 18, 2008
So many different cycles are going to align here and there just by random chance.

Could not agree more such as CO2 and temperature correlation. Like I said if you believe the science is settled there is no need to investigate. BTW why so anonymous Steve?
Member Since: August 26, 2005 Posts: 1030 Comments: 11197
286. SteveBloom
5:40 PM PST on February 18, 2008
Re #279: jer, that paper stands as proof that *you* could probably get published somewhere. BTW, if you look hard enough you'll find a similar one on South Africa. It too disappeared without a trace (scientifically speaking, although as we can see everything acquires a certain permanence in the age of the internet). Both papers are a monument to the proposition that it's easy to find apparent correlations between solar activity and the weather. So many different cycles are going to align here and there just by random chance.
285. SteveBloom
5:32 PM PST on February 18, 2008
Re #283: Based on your comments we're talking the hard stuff here, not Edna (whatever that may be).
284. SteveBloom
5:32 PM PST on February 18, 2008
Re #281: Progress at last. I will readily agree (as I have before) that they can and do have a short-term effect on average global surface temp, although these eventually even out. You've been speculating about a possible long-term influence, though. It's clear enough from your comments above that you have no basis for such an assertion, as in:

"I would like to read a paper published in the last two years that goes to some length to explain PDO, how it changes, why it changes and what are it's effects in detail. If anyone could find such a paper I would greatly apppreciate it. This paper will also have to contain no reference to global warming induced climate change (there is no specific reason for me to look for a paper on PDO, I just want to see a paper that isn't full of global warming rhetoric). Remember, this paper should have been published within the previous two years (one would think such a paper would be easy to find since we are in the midst of a PDO regime shift, currently)."

OTOH it's good to want to learn something about this. As I told you, though, you're unlikely to find a PDO paper that doesn't mention global warming since the period of the PDO is so long (50 to 100 years) that global warming will have a major impact on it.

In terms of the paper, you can find one in a couple of minutes with Google Scholar. Use the "advanced" window to limit the search to the last couple of years.
283. latitude25
1:17 AM GMT on February 19, 2008
However, to discount their influence on global climate because they are not 'a forcing' is ridiculous.

exactly, "simply" is a hoot.

I don't drink Edna.
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282. SteveBloom
5:06 PM PST on February 18, 2008
Re #280: lat, you revel in your ignorance. Have another drink.

281. sullivanweather
8:08 PM EST on February 18, 2008
To give Bloom credit he is right.

Oscillation regime shifts are simply internal climatic rearrangements of the climate system.

However, to discount their influence on global climate because they are not 'a forcing' is ridiculous.
Member Since: March 8, 2007 Posts: 273 Comments: 12612
280. latitude25
12:56 AM GMT on February 19, 2008
276. SteveBloom 12:27 AM GMT on February 19, 2008
They are simply internal rearrangements of the climate system.

What? rotfl

Steve you are a hoot.
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279. sebastianjer
7:59 PM EST on February 18, 2008
Sull, climate oscillations are not forcings like GHGs or irradiance insolation changes. They are simply internal rearrangements of the climate system.

Unless of course solar irradiance is responsible for PDO AMO etc. then wouldn't that show that PDO etc. are not just simply internal rearrangements of the climate systembut a product of solar irradiance. Which I believe would be considered a forcing agent.

Abstract

The effects of solar variability on regional climate time series were examined using a sequence of physical connections between total solar irradiance (TSI) modulated by galactic cosmic rays (GCRs), and ocean and atmospheric patterns that affect precipitation and streamflow. The solar energy reaching the Earth%u2019s surface and its oceans is thought to be controlled through an interaction between TSI and GCRs, which are theorized to ionize the atmosphere and increase cloud formation and its resultant albedo. High (low) GCR flux may promote cloudiness (clear skies) and higher (lower) albedo at the same time that TSI is lowest (highest) in the solar cycle which in turn creates cooler (warmer) ocean temperature anomalies. These anomalies have been shown to affect atmospheric flow patterns and ultimately affect precipitation over the Midwestern United States. This investigation identified a relation among TSI and geomagnetic index aa (GI-AA), and streamflow in the Mississippi River Basin for the period 1878%u20132004. The GI-AA was used as a proxy for GCRs. The lag time between the solar signal and streamflow in the Mississippi River at St. Louis, Missouri is approximately 34 years. The current drought (1999%u20132007) in the Mississippi River Basin appears to be caused by a period of lower solar activity that occurred between 1963 and 1977. There appears to be a solar %u201Cfingerprint%u201D that can be detected in climatic time series in other regions of the world, with each series having a unique lag time between the solar signal and the hydroclimatic response. A progression of increasing lag times can be spatially linked to the ocean conveyor belt, which may transport the solar signal over a time span of several decades. The lag times for any one region vary slightly and may be linked to the fluctuations in the velocity of the ocean conveyor belt.

Source

Of course if the science is settled there is no sense in following up on this study
Member Since: August 26, 2005 Posts: 1030 Comments: 11197
278. sullivanweather
7:29 PM EST on February 18, 2008
Bloom,

According to your reasoning climatic oscillations such as ENSO, PDO, etc should have no effect what-so-ever on global temperatures which is false as proven by the recent downturn in global temperatures due to the current La Nina event.

The data backs my claim...if not, prove otherwise.
Member Since: March 8, 2007 Posts: 273 Comments: 12612
276. SteveBloom
4:21 PM PST on February 18, 2008
Re #275: Sull, climate oscillations are not forcings like GHGs or irradiance insolation changes. They are simply internal rearrangements of the climate system. The science does not support your views on this.
275. sullivanweather
6:29 PM EST on February 18, 2008
Bloom,

We don't even have reliable global records for temperature over a long enough period of time to be able to tell if these climatic oscillations affect the "the long-term global climate average".

The Arctic oscillation is a short-term climatic oscillation, but PDO, AMO are more long term (~30 years)

Up until recently we were in a warm phase of both PDO AND AMO. It now appears as if PDO is entering it's cool phase, meanwhile AMO is still in its warm phase.

The last time both were in cool phase was in 1976 when global temperatures, ironically, bottomed out for the time period of 1940-present.
Member Since: March 8, 2007 Posts: 273 Comments: 12612
274. sebastianjer
6:23 PM EST on February 18, 2008

Bottom line - solar forcing can't account for direction and magnitude of change.

What direction? Even giving 1998 the record as warmest year in a millennium( not true) but will say it is-the direction since then is down.

What magnitude? A 1 degC increase in over a century with a downward trend since.

On top of that you can not even specify how much of the directional magnitude is man made and how much is natural. Sad

JER
Member Since: August 26, 2005 Posts: 1030 Comments: 11197
273. SteveBloom
3:24 PM PST on February 18, 2008
Re #267: The question is whether the PDO or any other climate oscillation affects the long-term global climate average. No.

That said, as we appear to be seeing now with the Arctic Oscillation, increased warming will affect the behavior of those ocscillations. That might even cool off some areas for a while, but will it do much to the long-term trend? No.

272. moonlightcowboy
11:16 PM GMT on February 18, 2008
271. counters 11:11 PM GMT on February 18, 2008
Yawn. Does this diatribe even warrant a decent response?


Evidently! Conscious bothering you? LOL

All of this reminds me of the statement: "Can't see the forest for the trees!" The AGW advocates and associated politics fit this statement perfectly.
When one steps away from his immediate surroundings and takes a "bigger" look around, it's easier to see things as they really are - and not through rose-colored glasses.
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271. counters
11:09 PM GMT on February 18, 2008
re #269:

"-- So, instead of saying "we don't know" let's just manipulate SST data to conform to an expected outcome in order to generate research money. Blame man, and suddenly blank checks get passed around. LOL, one can not find truth based on a lie. But, it sure is fun spending OPM isn't it? LOL. Unfortunately, tons of money is being mis-spent and without regard to truth. Ex: how it's being used in grade school curriculums to scare our young children. That's an abomination imo!"

Yawn. Does this diatribe even warrant a decent response?
Member Since: February 4, 2008 Posts: 0 Comments: 166
270. SteveBloom
2:03 PM PST on February 18, 2008
Re #266: I once heard something about Man being made in God's image. As the Hitchhiker's Guide line goes, "That explains a lot."

269. moonlightcowboy
9:47 PM GMT on February 18, 2008
268. streamtracker 9:45 PM GMT on February 18, 2008
Bottom line - solar forcing can't account for direction and magnitude of change.


-- So, instead of saying "we don't know" let's just manipulate SST data to conform to an expected outcome in order to generate research money. Blame man, and suddenly blank checks get passed around. LOL, one can not find truth based on a lie. But, it sure is fun spending OPM isn't it? LOL. Unfortunately, tons of money is being mis-spent and without regard to truth. Ex: how it's being used in grade school curriculums to scare our young children. That's an abomination imo!

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268. streamtracker
9:30 PM GMT on February 18, 2008
Cowboy,

Maybe, if some of these advocates placed their efforts on the real reason the earth is warming or cooling: the sun; they could still get all the grant money needed for research and livelihoods. That certainly seems all the more worthwhile, and puts the science back where it belongs - based in fact instead of illusion!

There has been lots of research focused on solar forcings and it is even reported in the dreaded IPCC report. Just a quick search of one database yield 150 papers on solar forcings in last 5 years.

Bottom line - solar forcing can't account for direction and magnitude of change.
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267. sullivanweather
4:35 PM EST on February 18, 2008
Streamtracker,

I've read several papers (although I don't have them bookmarked, unfortunately) that goes to great length to explain how changes in PDO directly effect the climate across North America as a whole.

You cannot deny that phases of the PDO affect the climate here. Typically, warm phase of PDO brings much milder air over the North American continent than then cold phase of the PDO.

Perhaps I'll do a search later and see iof I can find these papers.

I suggest that you should do the same. You seem to know an awful lot about papers concerning human induced changes in climate due to increased GHG's but meanwhile seem very dismissive of natrual cyclical changes in oceanic oscillations. Meanwhile the oceans have a much greater effect on climate, currently speaking, than GHG's do.
Member Since: March 8, 2007 Posts: 273 Comments: 12612
266. quasigeostropic
9:30 PM GMT on February 18, 2008
If changes is GHG's are not the causal mechanism, what is? The period of sustained increase started in the 1960's (yeah there are ups and downs, but it is a predominately upward trend). If there is something else that is causing this what is it? If it is cyclical it would a have a periodicity of about a century? What cycles at that rate? And if there is something that does, is it in phase with the upward trend?

Easy answer: WE DONT KNOW! And we most likely will never know. The only Being that knows everything PERFECTLY is God.
Member Since: November 20, 2007 Posts: 21 Comments: 192
265. streamtracker
9:25 PM GMT on February 18, 2008
Sullivan the data I present also support a warming trend over the twenty year period (comment #253).

Also the goal of my series of posts has nothing to do with proving you wrong or that you are dismissive. Rather it was to compile information about climate change in the NE.

#252 That compels me to do two things. First, is to think that Sullivan is a smart guy and I probably should look into my assumption that the NE is in a sustained warming trend. Second, to report what I found especially if it is counter to what you wrote.(the indicators show an increasing trend during both the a 20, 30, 40 and 50 period)

I think I've presented data that makes a compelling case that we have had a sustained period of change in winter and spring climate in the NE.

Why are you so focused on a perceived slight? I made it very clear that I might be misunderstanding you:

Part of our disagreement here might have to do with the extent of the area we are referring to. I am specifically talking about New England, not the northeast as whole.

I think we are also arguing about different time periods.


So back to the debate?

If changes is GHG's are not the causal mechanism, what is? The period of sustained increase started in the 1960's (yeah there are ups and downs, but it is a predominately upward trend). If there is something else that is causing this what is it? If it is cyclical it would a have a periodicity of about a century? What cycles at that rate? And if there is something that does, is it in phase with the upward trend?
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264. quasigeostropic
9:21 PM GMT on February 18, 2008
That's what the climate models are, a synthesis of our knowledge of the causation of the earth's climate.

causation eh....So we have thousands of scientists who dispute your Co2 theory...The fact that there is nowhere near a consensus means this science is very much still a theory. And by saying that because someone disagrees with you that they are "intentionally misunderstanding the facts" or "denying the truth" shows your intolerance to multiple other scientist's opinions. Graphs and stuff will never fully explain our earth/climate system and using faulty data to start off with means everything built off of that will be skewed/flawed...basically what JER/moon have explained to you already....
Member Since: November 20, 2007 Posts: 21 Comments: 192
263. moonlightcowboy
8:46 PM GMT on February 18, 2008
(1 plus 1 = 2, 2 plus 1 = 3, 3 plus 1 = 4) - These are undisputed facts.

* Uncontrolled placement of SS plus temps = Inaccurate data
* SST plus manipulation = Manipulated inaccurate data
* Manipulated inaccurate data plus expected outcome = Bad data molded to fit agenda.

These are NOT facts, but rather lackluster variables that support NO specific, discernable scientific conclusion other than roughly measured, tainted, bad data.


No consensus can be drawn from bad data unless it's bad consensus! The six or seven IPCC scientists credited with coming up with ACO2/Temp-related conclusions using this manipulated data simply is NOT consensus! There can be no consensus based on faulty and inaccurate collected data.

Another comment has been made that for every warmer SST reported, there is another reported cooler. And, this makes what sense? LMAO, none! It's still just simply bad data! No matter how hard the AGW advocates have tried(to date), there simply is NO conclusive, scientific fact that man is causing the planet to warm.

(edit)Maybe, if some of these advocates placed their efforts on the likely, real reason the earth is warming or cooling: the sun; they could still get all the grant money needed for research and livelihoods. That certainly seems all the more worthwhile, and puts the science back where it belongs - based in fact instead of illusion!

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262. sullivanweather
4:07 PM EST on February 18, 2008
Another thing about the Albany data.

I don't know if there was a move to where they recorded temperatures, which there very well could have been.

That could explain why the growing seasons took a sharp downturn in the 1950's.

Member Since: March 8, 2007 Posts: 273 Comments: 12612
261. sullivanweather
3:59 PM EST on February 18, 2008
Bloom,

That is why using growing seasons as a climate indicator is poor. Variability in weather, such as a freeze which only takes one day (very noisy), can lead to figures that point in opposite directions to a climatic signal, such as the ice-out dates that streamtracker pointed out.

2007, although one of the warmest years in history, brought the Southeast US one of their shortest growing seasons on record. They had a very late freeze in April and a very early freeze in October.
Member Since: March 8, 2007 Posts: 273 Comments: 12612
260. SteveBloom
12:44 PM PST on February 18, 2008
Re #257: Thanks, Sull. What's interesting is that Albany seems to have some unusual climate behavior. This statistic for 1998 (a very warm year nationally as well as globally) is strange to the point of bizarre. I think it might be better to look at a larger region.
259. SteveBloom
12:41 PM PST on February 18, 2008
Re #s 246/51/54: It's funny how these articles never mention that about six months back someone audited the "auditors" by checking data from the top-rated stations identified up to that time. Here's the upshot straight from McIntyre himself:

"John V has posted some graphics recently arguing that CRN1-2 yielded pretty much the same results as major temperature indices and, in some sense, vindicated these results. As Gavin Schmidt has pointed out, the U.S. is only 2% of the world%u2019s surface; and as I%u2019ve observed on many occasions, the statistical methodologies and data quality in the U.S. are different from the ROW, as is the history."

"In some sense." *snork* He really didn't want to say it, did he?

That the existing network has all kinds of problem is news to nobody. It wasn't designed to collect climate-quality data, but fortunately the scientists working on this stuff understand how to make the necessary adjustments.

BTW, in the mid-'90s NOAA decided that it would be better to build a new climate sensor network from scratch (being completed just now) than to try to upgrade the present one. One of the important reasons for this is that while the present network is fine for the large-scale stuff, it's lousy for input to regional climate models (RCMs). So, unsurprisingly, the scientists are way ahead of the amateur "auditors."

An interesting aspect of this is that the "auditors" are using part of the siting standards for the new network as the criteria to test the existing sites. It will perhaps comne as no surprise that those standards aren't very useful for such a purpose since all they do is describe a *possible* range of error (based on entirely seat-of-the-pants estimates). That's all they can do since it turns out that microsite biases are virtually impossible to measureamd is why it never occurred to any scientist to try to apply the siting standards to the existing network. Even so, we saw what happened when that was done.
258. sebastianjer
3:40 PM EST on February 18, 2008
Sully
Please don't confuse the science with the facts, lol
Member Since: August 26, 2005 Posts: 1030 Comments: 11197
257. sullivanweather
3:36 PM EST on February 18, 2008
Albany, NY growing seasons
Member Since: March 8, 2007 Posts: 273 Comments: 12612
256. sullivanweather
3:11 PM EST on February 18, 2008
StreamTracker, This is what I mean about garbling...

-------

252. streamtracker 1:29 PM EST on February 18, 2008
Sullivan,

No garbling going on. You were dismissive of my post on invasives and climate change in NE, so I compiled some information to test my assertion that NE climate has been warming since 1960's.

When you say things like:
Besides, using a mere two decades to try and back this claim that the climate has changed is nonsense. Especially while during this 20 year period we had one of the coldest stretches of weather ever recorded (February '94).






211. streamtracker

This species has been moving slowly northward as winter temperatures have increased over the last two decades

212. sullivanweather

Especially while during this 20 year period we had one of the coldest stretches of weather ever recorded (February '94).


-----------

234. streamtracker 4:36 PM EST on February 17, 2008
Sullivan,

The Bradshaw lab did their own measurements at the sites they study the mosquitoes and they found a 4F rise over the 30 years they have been working at their sites.
Furthermore, if we are talking about rapid (decadal) response to climate change by plants and animals then certainly since the 1960's winters are warmer.



-------

You didn't mention anything about using a 40 year sampling until many posts later but then take my posts out of context to try and prove me as being dismissive of your posts. That is a garble, my friend.

Member Since: March 8, 2007 Posts: 273 Comments: 12612
255. SteveBloom
12:15 PM PST on February 18, 2008
Re #249: Sull, regarding the growing season stats, do you have a link? It's curious that a period with major vulcanism (Krakatoa) would have had a much longer growing season than at present.

Re your remark about short-term warming trends or the lack therof, be aware that if a strong La Nina or El Nino changes global temps by e.g. .2C (just eyeballing 1998), that's 10 years worth of the underlying GHG warming. So, what you've just illustrated is how easy it is for someone who knows a lot about the weather to fool themselves into thinking we may not have a problem.

Regarding the PDO, note that none of the experts on it agree with you.
254. streamtracker
6:52 PM GMT on February 18, 2008
Tropic, #251. You confound an unwarranted injected bias with a well founded systematic data correction. If you take out the urban stations (the one skeptics point to), that may have elevated temps because of heat island effect, you still get a very strong warming signal.

And thank you for elevating Global warming to the highest level for a scientific idea - that would be a theory.

A set of statements or principles devised to explain a group of facts or phenomena, especially one that has been repeatedly tested or is widely accepted and can be used to make predictions about natural phenomena. (Source)

And what is this you said? "correlation does not imply causation, although many scientists forget that golden rule" Your not aware of the work that been done over the last 25 years to explain the causation? Look up forcings. That's what the climate models are, a synthesis of our knowledge of the causation of the earth's climate.
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253. streamtracker
6:41 PM GMT on February 18, 2008
Here's two graphs to pounder regarding NE winter climate change.

Late Winter/Early Spring NE Temperature

Photobucket


Ice out dates for New England Lakes
Photobucket

(Both images are from: Historical changes in lake ice-out dates as indicators of climate change in New England, 1850-2000. Glenn A. Hodgkins et al. 2002. International Journal of Climatology Volume 22, Issue 15 , Pages 1819 - 1827)

First, the data here strongly suggest that the change in winter climate has been a century long trend. Second, note that there is an upward tick in the rate of change in the early 1960's. This corresponds to the increased rate of global change in average temperatures. While that may be a coincidence, it may also point to the link between the global changes and the local changes. In so far as you accept that the global changes are primarily due to changes in GHG's, this suggests that the local changes are also due to GHG's.

One caveat of this data set is that the data are primarily from Northern New England. I do not know how well this information would extrapolate to the rest of the NE.
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252. streamtracker
6:28 PM GMT on February 18, 2008
Sullivan,

No garbling going on. You were dismissive of my post on invasives and climate change in NE, so I compiled some information to test my assertion that NE climate has been warming since 1960's.

When you say things like:
Besides, using a mere two decades to try and back this claim that the climate has changed is nonsense. Especially while during this 20 year period we had one of the coldest stretches of weather ever recorded (February '94).

That compels me to do two things. First, is to think that Sullivan is a smart guy and I probably should look into my assumption that the NE is in a sustained warming trend. Second, to report what I found especially if it is counter to what you wrote.

When you make statements like above, you seem to have been minimizing the changes in winter climate and I found multiple lines of independent evidence to suggest there has been significant changes.

And yes if we inspect each of the indicators, we may find weaknesses (growing season), but combined they tell a compelling story.

I found the graph you presented of NE meteorological data a poor indicator of changes in winter climate when approaching it from the biological perspective. In New England, the winter season biologically begins in late Oct. and last until late March early April. Many of the indicators I presented integrate signals from a broader seasonal time period.



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251. quasigeostropic
1:01 PM EST on February 18, 2008
The issues regarding stations in urban areas is well known and compensated for in the analyzes.

The issues are well known, but throwing some statistical analysis in to "compensate" the skewed data doesn't fix the bias, it just places man's opinion mixed in with what went on in history..Graphs only explain fragmented times and places in history. It doesnt represent the whole.....correlation does not imply causation, although many scientists forget that golden rule.....man-made GW is pure theory, NOT fact.
Member Since: November 20, 2007 Posts: 21 Comments: 192
250. streamtracker
5:56 PM GMT on February 18, 2008
#246 The issues regarding stations in urban areas is well known and compensated for in the analyzes.
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249. sullivanweather
4:05 AM EST on February 18, 2008
Bloom,

National weather service.

By the way...we're currently seeing how much one minor climate oscillation (ENSO) is cooling things off.

PDO is also swinging negative, so we'll also see what that takes us.

Again, increased CO2 will probably temper these effects more so than they have in the past, but in a few short years we'll have a better understanding of how much influence CO2 has on climate...

It's going to continue to rise so temperatures should natrually follow. Unless, of course, CO2's effect is being grossly exaggerated.
Member Since: March 8, 2007 Posts: 273 Comments: 12612
248. SteveBloom
12:51 AM PST on February 18, 2008
Re #247: I don't believe I garbled a thing. You've said you don't think CO2 will warm things up very much and that soon enough other factors (you mention climate oscillations or a change in solar irradiance) will kick in to cool things off. Obviously Ricky and the other climate scientists think otherwise. What you haven't done is explain the reasoning behind your opposing view.

BTW, what's the source for those Albany growing season figures?
247. sullivanweather
3:20 AM EST on February 18, 2008
Bloom and Streamtracker,

Is it the goal of you both to garble my posts here?

I have said repeatedly that there are many factors that have given us the rise in temperatures seen over the 20th century, GHG's being one of them.

Member Since: March 8, 2007 Posts: 273 Comments: 12612
246. moonlightcowboy
8:19 AM GMT on February 18, 2008
As JER says, a well built house is only as good as its "foundation." These surface stations have been the foundation of the IPCC's case, and holes and cracks are continually being found in this foundation from a variety of variables. Obviously, without this "foundation" the rest of the house is just built out of cards - it won't stand.

This is a bit lengthy maybe (sorry), but imo, it clearly shows how surface station data has been manipulated.

How not to measure temperature, part 51.-complete article.

While we've taken some detours looking at some
of the amazing things that have happened
globally for temperature in January, with
another detour to the sun, our
www.surfacestations.org volunteers continue
their mission.

This NOAA USHCN climate station of record
#415018 in Lampasas, TX was found to be tucked
between a building, and two parking lots, one
with nearby vehicles. According to the
surveyor, it is right next to the ACE Hardware
store on the main street of town. While likely
representative of the temperature for downtown
Lampasas, one wonders how well it measures the
climate of the region.



View looking NE

In her survey, volunteer surveyor Julie K.
Stacy noted the proximity to the building and
parking, which will certainly affect Tmin at
night due to IR radiance. Daytime Tmax is
likely affected by the large amount of asphalt
and concrete in the area around the sensor. The
main street of the town (28 ft from US 183) and
the ACE Hardware parking lot are visible in
this photo below:



View looking south

Google Earth shows just how much asphalt and
buildings there are around the sensor.


According to NCDC's MMS database, the Lampasas
climate station has been at this location since
10-01-2000.Previous location was an observer
residence, which appears to have been a
park-like location according to MMS location
map. The sensor was apparently converted to the
MMTS style seen in the photo in 1986, so the
move did not include an equipment change. See
the complete survey album here.


But the big surprise of just how bad this
location is came from the NASA GISS plot of
temperature. It clearly showed the results of
the move to this location, causing a jump in
temperature almost off the current graph scale.
Note that before the move, the temperature
trend of Lampasas was nearly flat from
1980-2000.


Click to see the full sized GISS record


Given the entropy of the measurement
environment, I have sincere doubts that anyone
can create an adjustment that will ascertain an
accurate trend from temperature data as badly
polluted as this. In my opinion, this station's
post 2000 data needs to be removed from the
climate record.

UPDATE:

Since there has been some discussion about how
well "adjustments" take care of such problems,
I thought I'd show you just how well the GISS
homogeneity adjustment works with this station.


Here is the GISS plot for Lampasas, TX with the
GISS homogeneity applied, I've changed the
color to red and labeled it to keep them
visually separate from the raw data shown in
the plot above.



Now here is the GISS raw data plot with the
homogeneity plot overlaid on it:



The effect is quite clear. The recent
"spurious" measurement remains unchanged, and
the past gets colder.

The result? An artificial warming trend for
this station that is created by GISS
adjustments.

Member Since: Posts: Comments:
245. SteveBloom
11:27 PM PST on February 17, 2008
Re #243: What we have here is a conscious decision to not face the facts, ST. The urge to pretend that something (climate oscillations or a change in solar irradiance in Sull's case) will come along to save us from ourselves is very strong.

You may be interested in this depressing study that concludes that many humans, perhaps a majority, are not wired so as to be able to perceive the problem. Interestingly this lack is not correlated with intelligence as such (although somebody who lacks it would probably have a rather short career as a physicist, e.g.):

"Understanding Public Complacency About Climate Change:
Adults' mental models of climate change violate conservation of matter
"

"Public attitudes about climate change reveal a contradiction. Surveys show most Americans believe climate change poses serious risks but also that reductions in greenhouse gas (GHG) emissions sufficient to stabilize atmospheric GHG concentrations or net radiative forcing can be deferred until there is greater evidence that climate change is harmful. US policymakers likewise argue it is prudent to wait and see whether climate change will cause substantial economic harm before undertaking policies to reduce emissions. Such wait-and-see policies erroneously presume climate change can be reversed quickly should harm become evident, underestimating substantial delays in the climate's response to anthropogenic forcing. We report experiments with highly educated adults-graduate students at MIT-showing widespread misunderstanding of the fundamental stock and flow relationships, including mass balance principles, that lead to long response delays. GHG emissions are now about twice the rate of GHG removal from the atmosphere. GHG concentrations will therefore continue to rise even if emissions fall, stabilizing only when emissions equal removal. In contrast, results show most subjects believe atmospheric GHG concentrations can be stabilized while emissions into the atmosphere continuously exceed the removal of GHGs from it. These beliefs-analogous to arguing a bathtub filled faster than it drains will never overflow-support wait-and-see policies but violate conservation of matter. Low public support for mitigation policies may be based more on misconceptions of climate dynamics than high discount rates or uncertainty about the risks of harmful climate change."
244. sullivanweather
11:28 PM EST on February 17, 2008
I think there's been a breakdown of communication somewhere, Streamtracker.

You keep making your assertions as if I had said there hasn't been any warming what-so-ever. As I keep saying, one can take a 30-40 year dataset from many different time periods and show that there has been warming and cooling. Right now we're in a warming trend, but we're also near the peak of the current warming trend. So either one of three things will happen.

It will continue getting warmer.
Temperatures will level.
It will begin to cool.

-----

Oh, a fast little bit of research I just did on growing seasons. Here's Albany, NY's growing seasons averaged by decade.

1870's (only 6 years of data beginning 1874) - 179 days
1880's - 189 days
1890's - 190 days
1900's - 173 days
1910's - 183 days
1920's - 189 days
1930's - 180 days
1940's - 148 days
1950's - 139 days
1960's - 141 days
1970's - 152 days
1980's - 154 days
1990's - 159 days
2000's (through 2006) - 163 days

I can also tell you that back in 2002 we had one of our shortest growing seasons since I've been growing crops. It snowed on May 18th and we had to replant everything. However, I believe that growing seasons is a poor tool to use since this can be most easily swayed by weather anomalies.
Member Since: March 8, 2007 Posts: 273 Comments: 12612
243. streamtracker
4:06 AM GMT on February 18, 2008
Sullivan,

I could just as easily say there's been no warming (a slight cooling even) since the early 1950's in Northeast winter temperatures. Data can be manipulated in many ways.

No you can't "just as easily". Why can't you? Because there are several lines of independent evidence that all converge on the same conclusion. If your going to make such a sweeping statement then you should attack each independent piece of evidence and show what's wrong with them.

Let's see there's:
The temperature data.
The river flow data.
The ice out data.
The earlier blooming dates.
The decrease in snow depth and increase in snow density.
The decreased geographic extent of winter snow cover.
The extended growing seasons.
The earlier arrival and nesting of migrant birds.
The earlier calling times of vernal pool dependent anurans.
The changes in migration dates of anadromous fish.

Please, explain all that and with a straight face say that the most likely explanation, with a high degree of confidence, is not that NE winters are warming? What is it then that accounts for all those indicators pointing in the same direction? I eagerly await a plausible hypothesis.

And how many years do you need to make a trend? Most of the variables I listed began to change in the early sixties. That is over 40 years of change in the same direction (yes of course there were ups and downs, but the trend line is clearly up).

Is it a coincidence that the upward trend in global temperatures and the NE climate indices's all take an upward turn at the same time in the early 1960s? Or is it not coincidence and it's all part of the global pattern of AGW?

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242. sullivanweather
10:17 PM EST on February 17, 2008
Streamtracker,

That all well and good, for now.

But 30 years ago in the late 70's we had experienced just as much cooling over the prior 30 years as warming we've seen over this most recent 30 years. Also of note is that winter temperatures in the late 1970's ('77, '78, '79) were the coldest on record nationwide. In fact 1979 was more than 1°F colder than the previous coldest winter on record.

I could just as easily say there's been no warming (a slight cooling even) since the early 1950's in Northeast winter temperatures. Data can be manipulated in many ways.

If 30 years from now we've gone up another 2-4 degrees then yes, there's a prolonged warming trend. But any trough to ridge temperature measurement is going to show warming.

Furthermore, there's no provable evidence that the sole causation of the most recent warming is due to greenhouse gasses, especially when similar warming trends are there in the brief climatic record that we have. Could it be a minor factor? yes... Could it be a major factor? yes...

Winter will always have the highest variability of any season temperaturewise so any short term noise is going to be magnified.
Member Since: March 8, 2007 Posts: 273 Comments: 12612
241. streamtracker
3:04 AM GMT on February 18, 2008
Some more sources of information on climate change in NE US.

1) Indicators of climate change in NE

From the summary:

Weather and climate in the Northeastern U.S. are arguably among the most variable in the world. This
variability on time scales from hours to years is the result of several factors that relate to the physical
geographical setting of the region, including its latitude, topography, and coastal orientation.
Despite this variability, the indicators of the Northeast'ss changing climate presented in this report provide
a coherent set of evidence of a region that is warming, especially over the last thirty years. This evidence
comes from a wide range of environments the atmosphere, the biosphere, the oceans, and snow and ice.


2) Another report states:

Average annual temperature has increased .8 degree C (1.4 degree F) over from 1900 to 2002,
according to data from 136 stations and 1 degree C (1.8 degree F) over just the last 33 years.

Average winter temperatures in the region have shown an even more dramatic
increase (1.4 degree C [2.5 degree F]and an even more striking 2.4 degree C (4.3 degree F) increase
between 1970 and 2002.

You can download it at: Cross Border Indicators of Climate Change over the Past Century: Northeastern United States and Canadian Maritime Region.

3) We'll have to keep an eye out for this research's publication. Right now all we have is a conference abstract from Elizabeth Burakowski.

Analysis of these four meteorological variables indicates that Northeast US winter temperatures are warming at a rate significantly greater than the global trend. In addition, monthly and seasonal snowfall is decreasing, and the number of days with snow deeper than three inches has decreased substantially.

You can view the abstract at: WINTERTIME CLIMATE TRENDS IN THE NORTHEASTERN UNITED STATES

Her work is also featured on the MSNBC website.

4) You can find an interactive map of NE climate change indicators at: Indicators of Climate Change in the Northeast

If you missed the other comments I posted, you'll find links to additional studies at comments 237, 238, 239, and 234.

Sullivan I think glancing at a graph has some utility, but there's nothing like really digging into the data and doing some analysis. And all of these studies point to one conclusion, NE winters are getting warmer.
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240. latitude25
11:53 PM GMT on February 17, 2008
232. sebastianjer 8:40 PM GMT on February 17, 2008
When we have mild winters here in central Florida we get a large migration of "snow birds".

These creatures have been known to cause roadcloganopus, a condition that we locals have learned to adapt to with much frustration.

It is believed based upon empirical evidence that global warming will mitigate this influx of these "snow birds" due to warmer climate conditions in their natural habitat.

Residence of central Florida, therefore have been known to wantonly disgorge tremendous amounts of CO2 into the atmosphere in order to alleviate themselves from the dreaded roadcloganopus which this yearly migration plagues much of the state with.


ROTFL.........
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239. streamtracker
11:39 PM GMT on February 17, 2008
This paper has some very interesting data on rates of change in both natural and anthropogenic forcing agents over a 22,000 year period, up to the present. Bottom line is that forcings due to anthropogenic agents have increased exponentially, in contrast natural variation in forcings (ghg, solar, volcanic) can not account for what is going on today.

Rates of change in natural and anthropogenic radiative forcing over the past 20,000 years.
Fortunat Joos* and Renato Spahni. 2008. PNAS | February 5, vol. 105, no. 5 pages 1425-1430

The rate of change of climate codetermines the global warming impacts on natural and socioeconomic systems and their capabilities to adapt. Establishing past rates of climate change from temperature proxy data remains difficult given their limited spatiotemporal resolution. In contrast, past greenhouse gas radiative forcing, causing climate to change, is well known from ice cores. We compare rates of change of anthropogenic forcing with rates of natural greenhouse gas forcing since the Last Glacial Maximum and of solar and volcanic forcing of the last millennium. The smoothing of atmospheric variations by the enclosure process of air into ice is computed with a firn diffusion and enclosure model. The 20th century increase in CO2 and its radiative forcing occurred more than an order of magnitude faster than any sustained change during the past 22,000 years. The average rate of increase in the radiative forcing not just from CO2 but from the combination of CO2, CH4, and N2O is larger during the Industrial Era than during any comparable period of at least the past 16,000 years. In addition, the decadal-to-century scale rate of change in anthropogenic forcing is unusually high in the context of the natural forcing variations (solar and volcanoes) of the past millennium. Our analysis implies that global climate change, which is anthropogenic in origin, is progressing at a speed that is unprecedented at least during the last 22,000 years.

This blog has a writeup on it and includes the key graph (click to expand).
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About RickyRood

I'm a professor at U Michigan and lead a course on climate change problem solving. These articles often come from and contribute to the course.

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