 Poster: A snowHead
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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It would be interesting to see total precipitation stats too.
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Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
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The question is when ?
Here in the UK the CC prediction is for wetter warmer winters and dryer hotter summers, with periods of great instability along the way.......at least i think it still is ? The problem is we are not seeing that. We are now in year 5 of dryer cooler winters and more variable summers, including last years which was distinctly not dry or hot. We are seeing almost the opposite of the model.
It feels to me as though we are back in a late 1970s/early to mid 1980s cycle, partciualrly the cold start to Spring (although last March was even more remarkable than this one for being so warm).
Sooner or later I assume this current cycle will end but right now it doesn't feel as though our UK climate change model is particularly accurate ?
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You need to Login to know who's really who.
You need to Login to know who's really who.
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0.75 degrees, is that really going to cause any problems?
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Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
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The article opens with a guy sitting in an office in Chamonix. Of all places, you only have to look around there to see that glaciers shrinking and disappearing isn't a phenomenon confined to the last 100 years.
Look at the temperature guestimates for the last 10,000 years and the trend over the last half of that period seems to be (worryingly) towards colder averages. Of course there is so much argument over the data it's hard to draw conclusions.
Two opposing interpretations of the same data are represented in the graphs here:
http://hot-topic.co.nz/wp-content/uploads/2011/01/easterbrook_fig5.png
and
http://hot-topic.co.nz/wp-content/uploads/2011/01/GISP210klarge.png
Either way, it looks like were at the cooler end of the spectrum.
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You'll need to Register first of course.
You'll need to Register first of course.
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To what extent has new thinking on changes in the jet stream seen this spring been incorporated into models for our part of the world?
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^ We have had ice ages in the past and the earth has been both much cooler and also much warmer over the last 10 000 years.
However at present we are in a period where the average temperature of the earth seems to be increasing much faster than it ever has before. The average rise over the last 30 years of approx "1-2C" is significant and large - and previously unprecedented. A handful of cold, or warm, winters mean nothing on their own. Climate change need to be measured over a longer period - but does seem to be real and measurable.
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| 0.75 degrees, is that really going to cause any problems? |
1 degree warmer = snow line approx 300m higher
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| To what extent has new thinking on changes in the jet stream seen this spring been incorporated into models for our part of the world? |
Lots of unknown factors mean the "models" and "predictions" may be wrong.
However that doesn't mean global warming isn't happening.
For example : what will happen when the arctic ice melts and cool the oceans ?
Is this what is causing the jet stream to deviate further south (etc).
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The other unknown for the models is how Gulf Stream could be affected which could be bad news for us but good news for Scottish Skiing 
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You'll get to see more forums and be part of the best ski club on the net.
You'll get to see more forums and be part of the best ski club on the net.
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www.chasingice.com, if you get a chance to see this film, it really shows the effect of the changes in our environment in a very visual way.
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So does anyone have any precipitation stats? The whole thing is pretty meaningless without them. I can live with 300m less vert if I get 3m of extra pow at the top...
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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Haggis_Trap, the earth hasn't warmed for 15 years. That's long enough to require some explaining. There's a lot of argument going on as to why, including between many of the "consensus" scientists, who are taking different positions on this. The proffered explanations are that:
(1) the climate system is not as sensitive as once thought to CO2 or at least the sensitivity is at the low end of the wide range of previous expectations - there has been a whole spate of papers recently arguing that
(2) the heating caused by an excess of inbound over outbound radiation is being distributed in deep ocean layers (depending on how deep, and given the immense heat capacity of the oceans, that means a radiative imbalance could be sustained for an awful long time before harmful consequences are felt)
(3) aerosol pollutants from newly industrialised nations could be absorbing more inbound radiation, so that there is less of a radiative imbalance than previously assumed.
I suppose some combination of the above could have caused the observed stasis.
Interesting times.
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And love to help out and answer questions and of course, read each other's snow reports.
And love to help out and answer questions and of course, read each other's snow reports.
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1 degree warmer = snow line approx 300m higher
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I thought the standard unsaturated lapse rate was about 1C per 100m. Therefore 1 degree warmer is snow line 100m higher surely?
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| laundryman wrote: |
| Haggis_Trap, the earth hasn't warmed for 15 years.. |
15 years is nothing in terms of climate - which must be measured over at least 30 years.
There are many possible reasons why the earth may not currently be warming.
1. Perhaps we are in a colder cycle due to sun spots ?
2. Perhaps the melted arctic ice has cooled the oceans ?
3. .... or perhaps CO2 does actually have less effect than we thought ?
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| I thought the standard unsaturated lapse rate was about 1C per 100m. Therefore 1 degree warmer is snow line 100m higher surely? |
Correct.... (depending if the air is dry or cold).
Lapse rate just tells us where snow falls on a given day. Not where the snow line would lie.
Bigger % of snow falling as rain could potentially raise the expected snow line more than lapse rate alone would suggest.
Either way a global rise of 2C would be noticeable (We are already losing the European glaciers at a fast rate).
5C could be catastrophic for some regions.
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You know it makes sense.
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Haggis_Trap, 15 years of warming was enough for many scientists to proclaim that the fingerprint of catastrophic anthropogenic global warming had been revealed to a high level of probability. The subsequent 15 years has fallen outside the envelope predicted by those scientists' models, upon which some still rely. Ergo, there is some explaining to be done, and scientists (including some of those who must have been surprised by recent developments) are trying to do it, exploring the avenues I mentioned in my previous post.
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Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
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Poster: A snowHead
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Haggis_Trap, your statistic is consistent with the fact that the world hasn't got any warmer in the last 15 years. That would be an interesting thing to explain, don't you think? If we only have a series of unverified and conflicting conjectures, we can hardly have much confidence in predictions for the next 15 or 30 years. Which would be rather useful.
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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^ It is a fact the earth has become much warmer over the last 100 years.
In climate change terms 15 years in statistically miniscule, even if you do believe the rate of warming may have currently slowed.
(Basically its like saying that 1 cold week = cold summer)
Obviously scientists don't know what will happen with 100% certainty. Nor will they ever agree.
However given the possible outcomes it is naive to stick head in sand and pretend that everything will probably be ok.
http://www.carbonbrief.org/profiles/has-global-warming-stopped
Last edited by Obviously A snowHead isn't a real person on Fri 19-04-13 16:49; edited 2 times in total
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Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
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You need to Login to know who's really who.
You need to Login to know who's really who.
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if its not getting any warmer how come the vast majority of the worlds glaciers have shrunk, Larsen was 2002, if you look at Iceland and Greenland their glaciers are shrinking.
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Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
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| Haggis_Trap wrote: |
| In climate change terms 15 years in statistically miniscule. |
As I say, many climate scientists do not believe it is negligible (and didn't believe 15 years warming following the 1940-1975 slight cooling was negligible either; they constructed the (fraying) "consensus" theory from it). I don't think sticking fingers in the ears is any more constructive than sticking heads in sand. I hope some more convincing climate models can be constructed, that have greater predictive power. That is what scientific progress is about.
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You'll need to Register first of course.
You'll need to Register first of course.
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^ Clearly no one can make accurate climate predictions based on just 15 years of data.
(1 cold week does not equal a cold summer).
Just because some scientists haven't been 100% accurate in the past doesn't mean that progress is not being made.
Above plot shows 4 independent surveys, from respected sources, that all say planet has got warmer in the last 100 years.
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| Haggis_Trap wrote: |
| ^ Clearly no one can make accurate climate predictions based on just 15 years of data. |
That has now proven to be the case for the period of data from 1975-1990 (or to the mid/late 90s, if you like). That is why ignoring an extra 15 years of data is not sensible. But fortunately it is not being altogether ignored; it's just that there is currently not much agreement on how the models should be re-worked to explain the new facts.
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^ Basically you are saying "no one knows 100% what will happen". Which is correct.
However the more important longer term warming trend indicates seems something is certainly changing ?
Given the possible serious outcome it is naive to be in denial.
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You'll get to see more forums and be part of the best ski club on the net.
You'll get to see more forums and be part of the best ski club on the net.
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Hmm. To quote the wikipedia article linked to earlier
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ving a reliable global temperature from the instrument data is not easy because the instruments are not evenly distributed across the planet, the hardware and observing locations have changed over the years, and there has been extensive land use change (such as urbanization) around some of the sites.
The calculation needs to filter out the changes that have occurred over time that are not climate related (e.g. urban heat islands), then interpolate across regions where instrument data has historically been sparse (e.g. in the southern hemisphere and at sea), before an average can be taken |
So the problems are how to measure global temperature in the first place, and then to determine how it has changed. There is no absolute way of doing that. Never mind, we have creative writing organizations like the University of East Anglia to assist us. That's all right then.
Last edited by You'll get to see more forums and be part of the best ski club on the net. on Fri 19-04-13 17:19; edited 1 time in total
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^ yip. clearly we can only use the data sources that we have access to and / or previously measured for 100 years.
these are getting better all the time as science and our understanding of the planet slowly improves.
climate change could easily result in some areas of the planet become warmer and others colder (as the gulf stream becomes weaker ?)
people are right to ask questions....
however very little of the data gathered indicates that longer term climate change is not a genuine potential concern with possible serious outcome ?
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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| Haggis_Trap wrote: |
^ Basically you are saying "no one knows 100% what will happen". Which is correct.
However the more important longer term warming trend indicates seems something is certainly changing ?
Given the possible serious outcome it is naive to be in denial. |
Yes, the world has become warmer over the last hundred years - as it has got warmer and colder in earlier centuries and over longer timescales too. In the 1900s, there were two major episodes of warming of roughly equal rate and magnitude; roughly centred on the 1930s and the 1980s. The former could not have been caused by CO2; the later may well have been to some degree. Since there have been static and slight cooling interludes as well (including currently), other variables are certainly at play. Until we understand them better, we cannot naively draw the best straight-line fit and extend it indefinitely. We could perhaps inoculate ourselves from further CO2-induced warming, but no such measures are without considerable cost, including health costs such as premature winter deaths due to expensive energy prices. So I think this issue calls for sober analysis, not "it's all hokum" or "we're all gonna fry".
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And love to help out and answer questions and of course, read each other's snow reports.
And love to help out and answer questions and of course, read each other's snow reports.
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Haggis_Trap, forgive me for being sceptical
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<3066> Thorne: I also think the science is being manipulated to put a political spin on it, which for all our sakes might not be too clever in the long run.
<4755> Overpeck: The trick may be to decide on the main message and use that to guid[e] what’s included and what is left out.
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Yes that link is from Fox News - who are not my favourite interpreters of the news. However, I don't think there's a dispute that those quotes are genuine:
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You know it makes sense.
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It is not disputed that there is global warming. This is happening because we are for the umpteenth time coming out of a glacial period and entering an interglacial period. The glaciers receding and polar ice caps melting back year on year is merely what happens every time the planet enters an interglacial period. Videos of crumbling ice at the foot of glaciers or polar ice sheets are often used to illustrate global warming but this is disingenuous as glaciers and the ice sheets extend and recede every single year with the seasons. It is also important to appreciate that our planet has spent 85% of its existence with no ice at its poles at all and has fluctuated between these two so-called "icehouse" and "greenhouse" states.
It is hypothesised that global warming is happening more quickly over the last half century or so and that the main reason is anthropogenic ie the planet is warming up more quickly recently and this is because of human activity. As laundryman said above this was prompted by 15 years of data which then influenced the overall recent trend from what was a slight cooling one to an upward one! There has been no rise (or fall) in global temperatures for the last 15 years despite not only continued but accelerated human activity that should have increased radiative forcing (eg increased burning of fossil fuels). If 15 years of data was enough to be worthy of regard before, it should be enough to be worthy of regard now, even if it is showing something that is not in the best interests of the climate scientists. I don't think it is a coincidence that what I consider to be an exaggerated rather than a proportionate or measured response to concern about global warming coincided with a time in academic science when competition for limited funds, impact factor and public interest became the imperatives for maintaining their livelihoods for many. It's now also a bandwagon for those in connected occupations and industries.
So far as the case for accelerated and anthropogenic global warming goes, this may indeed be true. However, it may also not be true, it may not be practicable to do anything about it and it may not be necessary to do anything about it. I read a lot of bits of the IPCC AR4 2007 when it came out. Though it's far from my field, to someone familiar with statistics and with skills in critical appraisal it's full of holes. Some concerns are the way that global temperature is measured (comparing apples and oranges, accuracy, representativeness, changes in definitions and what is included in the data), the conclusions on radiative forcing, the faith required for current climate models and things like sea-level projections, the overly-wide confidence intervals of some of the data presented as evidence, the general tone of the document that does not come across as impartial but out to make a point. Basically lots of ifs and maybes that depend on other ifs and maybes built on still more ifs and maybes isn't very convincing. That doesn't mean that it's a fabrication or not well-meaning, just that it does not represent good evidence for anthropogenic global warming, and I for one would not therefore feel ready to make big changes to my life on the strength of the current level of knowledge. I do believe in sustainability though which is a wholly different issue.
minor editing for clarity
Last edited by You know it makes sense. on Sat 20-04-13 13:42; edited 2 times in total
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Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
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^ yip 130 years is 'short term' compared to the history of the planet : hence the uncertainty in the models (we simply dont have enough data)
of course people would like to believe global warming is not happening, and that the oil wont eventually run out.....
would be very convenient. but the balance of evidence suggests otherwise.
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Poster: A snowHead
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| Haggis_Trap wrote: |
| of course people would like to believe global warming is not happening, and that the oil wont eventually run out..... |
For me this is the crux of the problem. There are lots of reasons to look for alternative & cheap energy supply to replace oil & gas, plus recycling to save sending commodities to land fill.
However, the association of these issues with the "climate change" debate means our political leaders are making poor decisions and are in the process of lumbering us with expensive energy, and that will be very bad news.
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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^ the problem is that governments make *all* their decisions on a short term economic basis.
no country decides to do the 'right thing' if it cost them too much. they certainly dont really care about climate change because it wont affect their next 5 years in office...
energy will get more expensive due to the number of people of the planet. the chineese and asians have growing expectations - the price of oil, a finite resource, can only go up (irrespective of climate change)
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