General Climate Change Discussion Continued:

[NorthNorfolkWeather]

I often say, I wish the politicians, plus the scientists who get involved with the political side, would get more involved with the general "sustainability, pollution and cleaning up our act" angle rather than just focusing on AGW when it comes to policymaking- for your last two sentences are spot on.

Hi TWS,

Don't often pop in here, but I enjoy a good ding dong I totally agree with you comment there. We should be encouraged to live 'Greener' lives, if only from the sustainability side. The problem is, as you said in a bit of your comment I cut, too many people want to get in on the act. I think politicians have a dim view of the electorate is that we are all plebs, and the only way to get us to do something is by scaring us

On the other hand, this 'Climategate' issue has just proved that the scientists are human and defend their patch, their ideas, with every means at their disposal, sometimes in the face of contradictory evidence. Someone else who did that, sometimes to the detriment of others, is now regarded as Britain's foremost scientist, Newton

Edited January 8, 2010 by NorthNorfolkWeather

[rob48]

Apologies all round.

Seems I was completely wrong previously.

Now I've got it.

Cold = only weather.

Warm = real climate.

That must be it.

[Devonian]

Apologies all round.

Seems I was completely wrong previously.

Now I've got it.

Cold = only weather.

Warm = real climate.

That must be it.

Well, put it this way, did you see the record breaking warm summers of 2003 or 2006 as proof of AGW? I very much doubt it...

It's about climate - weather over time - about picking the trend out of the noise.

[rob48]

Well, put it this way, did you see the record breaking warm summers of 2003 or 2006 as proof of AGW? I very much doubt it...

It's about climate - weather over time - about picking the trend out of the noise.

I saw them as hot summers. I've seen the three since then as rather cool, even if the nights were mild.

I've never seen any proof of AGW and don't expect to.

I've seen the last two winters as cold and very cold.

[Devonian]

I saw them as hot summers. I've seen the three since then as rather cool, even if the nights were mild.

I've never seen any proof of AGW and don't expect to.

I've seen the last two winters as cold and very cold.

I agree.

And what's the global trend of temperature been over the last period defined as climate (thirty years)?

[Solar Cycles]

I agree.

And what's the global trend of temperature been over the last period defined as climate (thirty years)?

20 years off rising global temps, and 10 years static temps. Now what does that tell us Dev?

[Methuselah]

20 years off rising global temps, and 10 years static temps. Now what does that tell us Dev?

Maybe that, for the timebeing at least, Natural Cycles and AGW are equal and opposite in their effects?

[VillagePlank]

If, for a time, we can forget about partisan terms, then I think, it will be most helpful. What shouldn't be brushed under the carpet is that the anomalies over the last decade have been above the climate average. This means that the climate is currently warmer than the average between 1970 and 2000.

If you suspect that weather stations have been cherry picked because they have been warmer than other local weather stations due to the urban heat island effect then, I'm afraid, that is a defacto admission that man can affect the climate - otherwise, where does such an effect come from? If man couldn't affect the weather/climate then there would be no UHI effect. It is probably wise to take a quick look over Iceberg's and Diessoli's work on anomalies and how they are resistant to outliers, too, on the Met Data thread.

On the other hand, we are measuring anomalies against an arbitrary background figure - so the extent of how much warmer it is (and it is warmer) is arbitrary and imposed - ie someone, somewhere has decided that either this thirty year period is the idealised climate, and thus we should measure against it, or it's simply convention. For sure, we need to measure against something, but the choice of selection of the period, as far as I can ascertain, is opaque, and therefore it appears arbitrary.

This measurement basis, for some hitherto reason that I've never been able to justify, has always made me uncomfortable. Personally, I think using the running median is the most helpful. I think that the median is a much better starting point for measuring climate since the median returns what the middle value is - so you take the middle value of the whole series. Here's what the 30 year median, for the CET, looks like ...

Indeed, the median is primarily used for skewed distributions, so that whilst there is a tacit agreement that the climate temperature distribution is skewed towards warmer as we go through time, scientists continue to use the arithmetic mean, instead of the median - where, arguably, the central point in the skewed distribution is best served from the calculation of the median. Perhaps, it is an effect of the 'dumbing' down of policy published to the general public?

It is noted that prominent opponents of AGW who are statisticians appear to avoid the median because of it's inherent, and, arguably immutable conclusion of a warming climate. After all, why use a simple statistic that the layman has a hope of understanding, when you can wrap it all up in the some of the most complex analysis known to man? Occams razor comes to mind ...

Anyway, I think that, colloquially speaking, we can see this as the running base-line of the CET, and we can see what's happened recently. The median only goes one way - up. For anyone to avoid this fact, it seems to me, is rather hiding their head in the sand. Indeed the arithmetic mean shows a "flattening out" of the CET at above average anomalous warmth (say about 0.3C above) It also dispells such notions that such a rate of change of temperature has not happened before, within an instrumental record - see CET period c1728.

Anyway, I think that the median is much more prescriptive, if a little ugly on the charts. For interest, here's the same data as the chart above, but 'zoomed' in for modern times:

You'll note that there is no flattening off of the CET in recent times, and, according to the ideas muted above, we should consider the CET to be in or around about 10C, now - which fits entirely with observation - so, if we consider, say 0.5C as the natural variation, according to this, it should not be unexpected to see a year, or two, with a CET of 9.5C - the important point is that cold weather is built into the system - we should expect it. - so anomalies of +/- 0.5C from 10C should be expected on the basis of this analysis. Personally, I think that natural temperature variation is more like 1.3C (stddev of CET set multiplied by 1.96) so, on that basis, CET returns of 11.3C and 8.7C are entirely possible to my mind - and anything that falls within that range, from 2009, appears to me to be unremarkable regardless of whatever record they might break.

(It is better to measure the frequency of above 10C, with frequency of below 10C over time - or for a running analysis measure the frequency of the current years analysis backwards in time on the same basis as the 10C example)

If one were to draw basic probabilities into the mix: given that the CET has generally been above the median for the last 15 years, one might expect that it should fall below for the next 15 years. However, extrapolation like this might be foolish, but it is also helpful - such that we can infer from a prediction such as this that if there is no increase in frequency of sub 10C CET returns over the next 15 years, then there must be some underlying factor that is modifying the climate. This heralds a move into more complex mathematics that probably doesn't sit well in a general thread, so I shall stop here.

If I get some more time, I'll do the same exercise with the global temperature set.

Edited January 9, 2010 by VillagePlank

[Methuselah]

Thanks for that post, VP...Very interesting ideas. :o

[VillagePlank]

Here's another interesting CET statistic ... this is the standard deviation for thirty years preceding the shown year multiplied by 1.96.

This is, perhaps, a crude measurement of what natural variation is apparent through time. So, for this year, the measurement is an expected natural variation of c1.25C. It would appear that the CET is entering a more variable period - but is this because it is warming, therfore the variance is higher? It is also very clear that the CET has been much more variable (pre-AGW) than it has been in the past.

I have to be honest, I don't quite know what to make of it - even whether or not it is a valid analysis. Anyone?

One thing is for sure, it doesn't look like this is randomly distributed to me, so surely it can tell us something?

Edited January 9, 2010 by VillagePlank

[Methuselah]

It tells me something I knew already (confirmation bias? ). That there's plenty of natural variation in the weather. I think???

[Devonian]

20 years off rising global temps, and 10 years static temps. Now what does that tell us Dev?

This.

[BLAST FROM THE PAST]

nope.

Therefore when I see deluded people on here and elsewhere gullibly gobbling up misinformation from the internet and spouting it as fact to other credible people I tend to get a wee bit frustrated! Be skeptical, yes, but be skeptical and open-minded in equal measure, and don't just believe what you want to believe unless there is sound corroborating evidence.

sss

Indeed, make sure folk are aware of the unproven science and all the uncertainties, SSS. Also the way you drew up the graph shows a classic reason for raw data not to be used.

BFTP

Edited January 9, 2010 by BLAST FROM THE PAST

[paul tall]

I agree.

And what's the global trend of temperature been over the last period defined as climate (thirty years)?

Interestingly, for the CET zone, the 1761-90 mean in January was 2.2ºC.

It is more than 2 degrees higher now. I'm using just one month, and a portion of England, so it is not "global" but certainly the temperature has been rising for 250 years not just 25-30, looking at that slice of data.

[Gray-Wolf]

Looking for Above Normal Temperatures? They are in the Arctic.

Submitted by Nick Sundt on Tue, 01/05/2010 - 20:58

Despite the cold air gripping much of the U.S., Europe and Asia, there is a very large area in the Northern Hemisphere where temperatures are well above normal: the Arctic. The National Snow and Ice Data Center (NSIDC) reported yesterday (5 January 2010) that "average air temperatures over the Arctic Ocean were much higher than normal" during December 2009. The extraordinary atmospheric conditions may be tied to climate change and to the rapid decline in Arctic sea ice, as well as other factors that cause climate to vary.

In our 24 December 2009 post (Don't be Fooled by Weather's Ups and Downs: The Climate is Warming -- Rapidly ) we explained that the odds of below normal temperatures are lower than they used to be -- but such conditions can still occur. More importantly, we emphasized that it is necessary to look at the big picture -- what is happening globally and over a longer period of time.

December is a case in point. While most of us experienced cold conditions and heard in the news only about similar conditions elsewhere in the Northern Hemisphere, vast and sparsely populated regions of the Arctic were well above normal. In Extreme negative phase of the Arctic Oscillation yields a warm Arctic (5 January 2010), the NSIDC included the figure below that dramatically contrasts above normal conditions in the Arctic with below normal temperatures in populated areas to the south.

Caption (from NSIDC): Map of air temperature anomalies for December 2009, at the 925 millibar level (roughly 1,000 meters [3,000 feet] above the surface) for the region north of 30 degrees N, shows warmer than usual temperatures over the Arctic Ocean and cooler than normal temperatures over central Eurasia, the United States and southwestern Canada. Areas in orange and red correspond to strong positive (warm) anomalies. Areas in blue and purple correspond to negative (cool) anomalies.

Credit: National Snow and Ice Data Center courtesy NOAA/ESRL Physical Sciences Division

Beyond giving us a more complete picture of temperatures in the Northern Hemisphere, there are other reasons why Arctic conditions matter. They not only affect the region's wildlife, ecosystems and communities, they have consequences that spill beyond the Arctic into the rest of the northern hemisphere -- and the entire planet. We explore many of these connections in Arctic Climate Feedbacks: Global Implications (PDF, 10.3MB).

Atmospheric pressure conditions in the Arctic have a lot to do with the temperature anomalies we are seeing. The atmospheric pressure in the Arctic and its relationship to mid-latitude pressure can fluctuate in a pattern known as the Arctic Oscillation (AO) and its status is quantified as an index value. When pressures are higher than normal in the Arctic and lower than normal in mid-latitudes, the AO is in its negative phase and the index is negative. The NSIDC reports that December's AO index value was -3.41, "the most negative value since at least 1950."

There is mounting evidence that atmospheric pressure patterns are changing in mid-latitudes and in the Arctic, that atmospheric circulation -- the large scale movement of air -- is changing, and that these changes are related to the rapid buildup of greenhouse gases in the atmosphere and to the associated decline in Arctic sea ice. While some are using the recent frigid conditions in the U.S. and other regions to raise doubts about climate change science, a wider perspective instead reinforces the science and the need to seriously address climate change by reducing emissions and preparing for the impacts that are increasingly evident.

For a recent discussion of the connection between Arctic climate change and weather changes in the northern hemisphere, see The Climate is Changing: The Arctic Dipole Emerges (Dr. Jeff Masters' WunderBlog, 11 December 2009). According to Masters:

"The dramatic loss of Arctic sea ice in recent years has created a fundamental new change in the atmospheric circulation in the Northern Hemisphere that has sped up sea ice loss and is affecting fall and winter weather across most of the Northern Hemisphere, according to several recent studies. " [emphasis added]

Stu Ostro at the Weather Channel also is raising the alarm about the anomalous atmospheric patterns that are emerging and how those changes are reflected in unusual weather, including extreme events such as flooding rains. As Ostro says in his posting, Off the Chain without a 'Cane (3 October 2009), climate change is altering the thickness (or depth) of different parts of the atmosphere, thereby "setting the table" for the unusual and sometimes extreme weather we are seeing. Ostro says:

"What we've been observing over and over again in recent years is exceptionally strong ridges of high pressure, sometimes accompanied by strong, persistent "cutoff lows" (upper-level lows cut off from the main jet stream) to the south of the ridges. The upshot: many weather events/patterns in recent years which have been topsy-turvy and/or produced precipitation extremes and temperature anomalies."

Ostro concludes that "[w]hile it's important to consider what may happen in 50 or 100 or 200 years, and debate what should be done about that via H.R. 2454 or other measures, we need to get a grip on what's happening *now*." (Ostro's emphasis).

See also:

• How Did this Happen? Blame the North Pole and the Equator. Capital Weather Gang (Washington Post), 21 Dec 2009.
• Study Links Low Arctic Sea Ice Levels to Drier Winters in the U.S. WWF Climate Blog (6 October 2009)
• Where on Earth is it Unusually Warm? Greenland and the Arctic Ocean, which is Full of Rotten Ice. Climate Progress, 6 January 2010.
• It's cold outside. What happened to global warming? Christian Science Monitor, 7 January 2010).
• The U.S. and European Cold Blast: Blame the NAO. By Jeff Masters, Wunder Blog (7 Jan 2010)

Edited January 9, 2010 by Gray-Wolf

[The PIT]

30 years in the time life time of planet earth means pfffff....

160 years means pfffffffff.....

Pauls Hudsons latest blog raises some interesting questions to debate. http://www.bbc.co.uk/blogs/paulhudson/

Pity he mentioned Joe B though.

[Gray-Wolf]

Seeing as we expect climate change to manifest first in the polar regions shouldn't we all be paying more attention to our cryosphere or is that just me?

I mean, had we not done such wicked things to our ozone we'd be viewing the changes we see in the arctic in both hemispheres.

As it is our past polluting allows sceptics to point at Antarctica (currently) and say "show me the warming" but what happens when the Ozone heals and the circumpolar winds, over summer, do not block the ingress of the past 40yrs of warming (the circumpolar winds have increased in velocity for that period effectively placing Antarctica in 'splendid isolation' from the rest of the planet)?

Do we see a massive increase in sea levels over a few short years as warm air rushes into the lowlands?

[paul tall]

Probably not.

[Devonian]

30 years in the time life time of planet earth means pfffff....

160 years means pfffffffff.....

So, if during a thirty year period a 5km asteroid slams into the planet that will mean pfffff?

I think not. Sudden relases of energy, or debis or ghg's can have long term effects.

Pauls Hudsons latest blog raises some interesting questions to debate. http://www.bbc.co.uk/blogs/paulhudson/

Pity he mentioned Joe B though.

And E&E which has published some truly egregious rubbish over the years.

Edited January 9, 2010 by Devonian

[Gray-Wolf]

Pit, please play nice. It's a new year and ,maybe, a new start?

Climate is changing, no argument there, Why? is the question.

If it's nature it'll sort .

If it's not then we are pushing buttons that we know not the consequence of.

Some of us have seen enough to make the call on which is which.

Dev and I are such folk.

If we are wrong we are safe.

If you are wrong we are goosed.

We could have made a difference but , should the likes of Dev and I be right, the chance has gone.

The reason we are here are politics and the sceptic's viewpoint and funding.

I've maintained this all along.

May the Gods prove Dev and I wrong, better for us all.

[Solar Cycles]

Pit, please play nice. It's a new year and ,maybe, a new start?

Climate is changing, no argument there, Why? is the question.

If it's nature it'll sort .

If it's not then we are pushing buttons that we know not the consequence of.

Some of us have seen enough to make the call on which is which.

Dev and I are such folk.

If we are wrong we are safe.

If you are wrong we are goosed.

We could have made a difference but , should the likes of Dev and I be right, the chance has gone.

The reason we are here are politics and the sceptic's viewpoint and funding.

I've maintained this all along.

May the Gods prove Dev and I wrong, better for us all.

God has spoken, your wrong!

[Gray-Wolf]

[rob48]

Pit, please play nice. It's a new year and ,maybe, a new start?

Climate is changing, no argument there, Why? is the question.

If it's nature it'll sort .

If it's not then we are pushing buttons that we know not the consequence of.

Some of us have seen enough to make the call on which is which.

Dev and I are such folk.

If we are wrong we are safe.

If you are wrong we are goosed.

We could have made a difference but , should the likes of Dev and I be right, the chance has gone.

The reason we are here are politics and the sceptic's viewpoint and funding.

I've maintained this all along.

May the Gods prove Dev and I wrong, better for us all.

Has there ever been a period when the climate hasn't been changing?

[The PIT]

Pit, please play nice. It's a new year and ,maybe, a new start?

Climate is changing, no argument there, Why? is the question.

If it's nature it'll sort .

If it's not then we are pushing buttons that we know not the consequence of.

Some of us have seen enough to make the call on which is which.

Dev and I are such folk.

If we are wrong we are safe.

If you are wrong we are goosed.

We could have made a difference but , should the likes of Dev and I be right, the chance has gone.

The reason we are here are politics and the sceptic's viewpoint and funding.

I've maintained this all along.

May the Gods prove Dev and I wrong, better for us all.

I was being nice GW pity the post got deleted as it was quite true.

You're right it is changing and will change all the time. The point I was trying to put across that people are thinking of the planet in terms of there own life span and not the life span of the planet. It's been warmer in the past although some deny it it's been colder in the past?

How much is this due to change in the continents position forcing changes in worlds currents?

How much effect does the sun have again some deny it has any?

A series of large volcanic eurptions does that have a tilting point on the climate?

Last of all man. Who has now created a large policital and industry around climate change which may or may not benefit us in the long run. Being positive it should result in a cleaner planet at least.

[Devonian]

Has there ever been a period when the climate hasn't been changing?

Bit of a red herring really - surely no one denies what you say?

There are lots of things that influence the Earth's atmosphere. The output of the Sun (and no one denies that either Pit), volcanoes, greenhouse gasses are some of them. Change the background level of either of those thing and the climate will change, change them for a short time and only the weather might change.

No one (again) denies a change to solar output will change the weather/climate. A big volcano (or a small one correctly delivered) also. we all pretty much agree on that science. Where we seem to part company is that while some of us also accept the science wrt the effect of ghgs some of us don't or wont.

Edited January 10, 2010 by Devonian