New Iceage? Much Evidence? - Global Cooling

[jethro]

Now up to 98 votes cast.....

Come on folks, speak up, have your say.

The climate issue will affect each and everyone of us, either directly through the weather experienced or indirectly through the measures taken to combat it. Surely you must have something to say?

There are a lot of threads to choose from in this section, please take a moment to have a look at them; join us nerdy climate freaks.

[Gowon]

I think winters are getting colder. But we're not getting a true reflection of temps due to thermometers being placed on UHI. This is worst in summers when temps always appear higher then it really is. So because of that I went for staying the same.

Higrade.

[Methuselah]

Not a shread of evidence to say it's decreasing but still a fair few votes for it....You've got to laugh...

Just what I was thinking. Maybe some folks think that Daily Mail editorials are evidence??

And, before I'm jumped on, that's nothing to do with what I want. It's just what the data (not the anecdote) show.

[barrel1234]

I think that for the short term (next 100 years or so) on average might get colder than at present although will probably stay above the pre 1998 short term average. But people better be careful about where they are waving thermometers around as population and urbanisation will increase so many weather stations will find themselves warmer just due to heat island effects.

^ as above mentioned, well done that man.

Edited September 27, 2010 by barrel1234

[Hiya]

He's not using 6 data points, he's comparing every data point through each century.

Yes he is. He is using the instances of a given occurence in 50 year intervals to generate 6 new data points. He could have used 20 year intervals, or 15 and generated more data points. The sample size isn't big enough to infer the conclusions he would like to make, especially since the subject - climate - is known to be dynamic. Plot up those 6 points and you get graph 1:

The conclusion is that number of instances of <8.99C CET years will remain very low in the future.* However your data set is too small to come to that conlusion, take graph 2 for example:

That is my own backwards extrapolation of a possible dataset from which the data for graph 1 could have been taken from. Now go back and look at your conclusion for graph 1, is it still valid? Does anyone who has read this think that graph 1's 6 points is enough?

* He used the >10C data, but I didn't notice until after I had made the excel sheet with the other data, however I presume that since trend of >10C is "very worrying" the <8.99 will also be similar.

[TonyH]

Oh I get it its all down to erroneous thermometer sitings?Never realised it was that simple, all those scientists fooled by the fact that the thermometers are all in towns and cities.

[Paul]

Yes he is. He is using the instances of a given occurence in 50 year intervals to generate 6 new data points.

He didn't use 6 data points, he used every year throughout the last 3 and a bit centuries to generate statistics split into 50 year sections. Climate needs to be looked at over a longer term as it smooths out the year to year (and longer) variations caused by weather patterns and other cycles to show you the underlying trend.

Therefore does splitting it down into 20 year intervals make the data any better or easier to draw reasonable conclusions from? Not in my opinion, more data points within the final statistics doesn't mean better results - for instance could you glean anything useful at all if you went the whole hog and just showed the stats from each year individually or every 5 years? No..

[The Future]

I may have misinterpreted the question. For those that voted "definetly increasing", are you expecting 2011 to be warmer than 2010? If so, do you think CO2 is the overriding factor; having a greater impact than La Nina, solar cycles etc?

I think 2011 will be cooler and surface temperatures are decreasing at this moment in time. Longer term, I don't know.

[barrel1234]

Oh I get it its all down to erroneous thermometer sitings?Never realised it was that simple, all those scientists fooled by the fact that the thermometers are all in towns and cities.

Did I say that? Come on, its not really sporting to try and ridulule someones post by adding a load of stuff that wasn't said? I think most people would realise that I was implying in a light hearted way that people could come up with very different conclusions depending on what data they use and we need to be careful about this. I havn't even disputed the fact that most people think its got warmer in recent years????? Jeez.

[Thundery wintry showers]

Global temperatures:

http://www.cru.uea.ac.uk/cru/info/warming/

http://www.ncdc.noaa.gov/img/climate/research/2009/global-jan-dec-error-bar.gif

CET:

http://hadobs.metoffice.com/hadcet/graphs/HadCET_graph_ylybars_uptodate.gif

http://www.climate-uk.com/provisional.htm

I've provided two sources for each. This year has so far bucked the recent trend in the CET, with temperatures close to the 1961-90 average, but the trend in the CET is clearly upward. Globally, this year isn't even bucking the trend, with temperatures similar to those of the record-breaking years of 1998 and 2005.

Unless we're using timeframes that are too short to be statistically meaningful, the evidence suggests that temperatures overall are still rising.

[My friends call me Dave]

This is a very divisive issue and the question is worded in slightly ambiguous fashion, as TWS pointed out the global trend is up but after a winter colder and longer than many can remember and a relatively dreary summer locally, the majority are going to feel like it is decreasing, no matter what the figures say.

Yay, first post after 7 years of lurking…

Edited September 27, 2010 by Headkyas

[Paul]

You've done it now Headkyas - you may never escape! Welcome to the world of posting

[jethro]

Yay, first post after 7 years of lurking…

Welcome, hope you stick around.

Come on peeps, let your inner nerd free....

[Nick B]

1. At some point in the earth's future it will return to an ice age state, but...

2. Much evidence? Of course there is - loads! But for what? That's the problem we have... We're getting very good at collecting data, however, not so good at knowing what it in fact is evidence for. Good scientists used to be the ones who when asked a question by the media and politicians, might respond, "It's too early to say..." because they recognised that it's important not to jump to snap conclusions when you are dealing with complex issues. We have a long way to go in understanding these issues before we can claim any science is 'settled', for instance.

3. I've put 'Stays the same', because the time frame was not defined in this poll. Maybe I should have put warming, because at some point in a few billion years, when the sun has grown in diameter, the earth will find itself dragged in and consumed, so that will definitely show a warming trend at that point...

If 50-100 years was meant, I think probably cooling. If 100-300 years, probably warming. Who knows after that? Will the human population then be 30 billion or maybe just 1/2 billion?

[TonyH]

"This consensus was sharply attacked by a few scientists. Some pulled out the old argument

that the advance of urbanization was biasing temperature readings. In fact, around 1990

meticulous re-analysis of old records had squeezed out the urban heat-island bias to the

satisfaction of all but the most stubborn critics. Moreover, long-term warming trends

showed up in various kinds of physical "proxy" data measured far from cities. To be sure,

in urban areas whatever global warming the greenhouse effect might be causing got a strong

addition of heat, so that the combination significantly raised the mortality from heat waves.

But the larger global warming trend was no statistical error."

From an interesting and accessible article on the subject:

http://www.aip.org/history/climate/20ctrend.htm

[Gowon]

Oh I get it its all down to erroneous thermometer sitings?Never realised it was that simple, all those scientists fooled by the fact that the thermometers are all in towns and cities.

Tonyh, with all due respect you need to tone it down a bit because dictatorial springs to mind. This is an "opinion" poll incase you had forgotten. Here's a few links to UHI.

badly place thermometers

urban heat islands’ effect

Higrade

[Methuselah]

Tonyh, with all due respect you need to tone it down a bit because dictatorial springs to mind. This is an "opinion" poll incase you had forgotten. Here's a few links to UHI.

badly place thermometers

urban heat islands’ effect

Higrade

It is indeed...And didn't a similar 'opinion' poll show that 25% of Americans think that the Sun goes round the Earth? Does that poll imply that 25% of the Sun goes round the Earth; or that the Sun goes round the Earth for 25% of the time?

IMO, what this (perfectly valid} experiment highlights could is likely one of two things: 1) that very many folks cannot differentiate data from belief, and/or 2) that the scientific community is having problems engaging with the populous???

My 'belief' is that probably the second problem is in most need of remedial action; becasue #1 comes as a direct result of #2????

[TonyH]

Tonyh, with all due respect you need to tone it down a bit because dictatorial springs to mind. This is an "opinion" poll incase you had forgotten. Here's a few links to UHI.

badly place thermometers

urban heat islands’ effect

Higrade

Back OT- if you cared to read that paper you will have seen that it states that UHI effect has been screened out of the statistics, and that the warming trend is happening across rural and city sites alike- its the TREND that is important.

[Gray-Wolf]

Back OT- if you cared to read that paper you will have seen that it states that UHI effect has been screened out of the statistics, and that the warming trend is happening across rural and city sites alike- its the TREND that is important.

I watched the late Stephen Schneider explain to a room of Ozzie sceptics how the UHI was removed from the temps and all there appeared quite satisfied that they'd been duped into thinking science was full of thickoes and not thinking wo/men who spot , and go to great lengths to correct for, such obvious occurances.

I feel it says more about the folk who understand so little that they can imagine such 'issues' being real as it ever does about 'the science'.

[The watcher]

Another way to look at things is (if someone could do so) to look at 2010's pattern and see if something similar occurred in the past....compare the cet's from them to see which was coldest. Then we could maybe see that when a similar winter occured in the past with similar blocking and SST's etc it was colder maybe because of the lower global averages?

[Guest mycroft]

Back OT- if you cared to read that paper you will have seen that it states that UHI effect has been screened out of the statistics, and that the warming trend is happening across rural and city sites alike- its the TREND that is important.

if thats true,any one care to guess whats happening here then.Posted this on another thread afew days back

http://notrickszone.com/2010/09/21/a-light-in-siberia/

Edited September 28, 2010 by mycroft

[Essan]

But the UHI effect is proof of AGW .......

(yeah, I know I'm a lone voice on that, but I cannot see how it can be otherwise)

[pottyprof]

But the UHI effect is proof of AGW .......

(yeah, I know I'm a lone voice on that, but I cannot see how it can be otherwise)

Nah...... You're not a lone voice. I agree totally with that point..

There's still the question of how much does it affect the overall picture though

[Paul]

I agree, it's hard (impossible) to buy into an argument which suggests that temperature readings are being skewed in terms of their accuracy because they're positioned close to built up areas. In my mind they're not being skewed at all, they're giving an accurate representation of the temperature on earth - you can't dismiss the heat rise associated with towns and cities as an inaccuracy, as it's real and a reflection of what's happening across the planet as the population grows.

[summer blizzard]

Yes he is. He is using the instances of a given occurence in 50 year intervals to generate 6 new data points. He could have used 20 year intervals, or 15 and generated more data points. The sample size isn't big enough to infer the conclusions he would like to make, especially since the subject - climate - is known to be dynamic. Plot up those 6 points and you get graph 1:

The conclusion is that number of instances of <8.99C CET years will remain very low in the future.* However your data set is too small to come to that conlusion, take graph 2 for example:

That is my own backwards extrapolation of a possible dataset from which the data for graph 1 could have been taken from. Now go back and look at your conclusion for graph 1, is it still valid? Does anyone who has read this think that graph 1's 6 points is enough?

* He used the >10C data, but I didn't notice until after I had made the excel sheet with the other data, however I presume that since trend of >10C is "very worrying" the <8.99 will also be similar.

Fair point, would you like me to split it into twenty year periods then?

My conclusion based on the available data over the fifty year intervals would be that the 2000-2049 period sees more 10C+ years than the fifty year period from 1950, and also that the number of 8.99C< years will also be less than the number of 10C+ years, a feat only achieved since 1700 by the 1950-1999 period.

As for global temperatures, 2011 is likely to be cooler than 2010, but 2013 will be warmer than 2010, provided no El Nino.