[alancalverd]

"Putting aside cause and affect...."? In a science forum? You jest, surely!

The fact that something has been illegal for 150 or 1500 years doesn't mean it doesn't happen.

There are no climate "experts". There is a wealth of weather data, around which some enthusiasts  have compiled various models based on the assumption that carbon dioxide drives climate, but to my mind an expert is someone who can look at the data, deduce a cause, and make a prediction that turns out to be more accurate than a guess. But then I'm a scientist, so I would say that, wouldn't I?

The problem with CO2 is that whilst it can be argued that the gas is transparent to incoming shortwave radiation but blocks outgoing longwave infrared, it is an insignificant part of the spectrum in both directions. The dominant factor is water, by several orders of magnitude, because
it is present in all three phases in the atmosphere
the phase changes involve massive quantities of energy
the H2O content of ambient air varies from near zero to over 10%
warm air can hold more water than cold air, givign a positive feedback if water is responsible for warming
the infrared absorption spectrum is extremely wide
as solid or liquid it can reflect over 90% of incoming or outgoing radiation
it covers most of the earth's surface, either as liquid, ice or loosely absorbed in rock and soil
as liquid or ice, it has a far higher specific heat capacity than most solids
we have no useful data on the content and distribution of water in the atmosphere
we have almost no historic data on sea temperature and even less data on the temperature distribution of the oceans
we have no historic data on polar climate before 1900

but we can measure CO2, so it's a scapegoat and a revenue source.

If you want a good sinusoid, look at the CO2 data from Mauna Loa. Whilst the mean has been rising steadily for ages, the annual curve peaks in May-June, when anthropogenic emission is at its lowest and plant growth is maximal, so something else is driving the CO2 level, and that something is temperature-dependent.

[Bored chemist]

Did you notice that almost all of this ........
wasn't actually about weather.

No, it was about wind, rain and forest fires. Weather must be about something else. Silly me.

Fairly silly.
 growing population (not weather) with increasing expectations of security (not weather) , is living in increasingly marginal land (not weather) , in increasingly flimsy buildings(not weather) . 100 years ago the only people who lived near the sea (not weather) were professional seafarers (not weather) with stone huts (not weather) and wooden boats (not weather) . Nowadays the coast is littered with pensioners(not weather)  in highrise flats(not weather)  and weekenders with plastic yachts,(not weather)  so an onshore Force 8 (My word! weather!) which used to mean a couple of days' lost work(not weather)  now means massive devastation(not weather)  and injury(not weather) . Flood plains (not weather) and water meadows(not weather)  are now concrete housing estates, (not weather) so a few wet cows (not weather)  have been replaced by an economic disaster. (not weather)  Most of Australia and California caught fire from time to time,(not weather)  and the natives made the most of fleeing animals (not weather) and new growth on the ashes(not weather) but modern farming methods(not weather)  (and farmers' bankers)(not weather)  are much less tolerant of nature.(not weather) "

[Bored chemist]

This difference is grounded in ...

The point is, the vast majority of the people, who discuss and have an opinion on climate science, are not climate experts.

Let me go back to CO2. Greenhouse gases should be able to block heat in two directions, since the insulation affect is IR dependent, which is the same in both directions.

OK, Firstly, the evidence supports the hypothesis that "This difference is grounded in ..."oil money.
Also, it's not the same in both directions- the Sun is, as you may be aware, hotter than the Earth, and this affects their emission spectrum.
As you say "The point is, the vast majority of the people, who discuss and have an opinion on climate science, are not climate experts. ".
You seem to have chosen a "truth" that tallies with your point of view, but is clearly nonsense.

That seems to happen a lot with those who pretend that you can put a forth blanket on the bed and pretend it has nothing to do with the fact that you get warmer.

[alancalverd]

You have missed the key point about "extreme weather". This journaliststic term is undefined but clearly has more to do with the perceived effect of weather, which is easy to determine by counting the cost of repairs, than the actual cause, which produces few photographs and very little of journalistic interest.

Winds of over 100 mph are common at the tops of mountains. So common that they don't make headlines because nobody is affected by them. 100 mph gusts rarely make the headlines outside of Hebridean local papers because very few people are affected by them and the architecture of Stornoway (indeed even the location of the city) has evolved to cope with them. But a 100 mph gust in the middle of London would make a lot of mess and therefore be reported as extreme. 

The point you have deliberately ignored is that by occupying meterologically marginal  territory, or modifying that territory to maximise the effect of the weather, people have, particularly over the last 50 years, turned normal weather (for the planet) into extreme events (for the population).  In other words, we have redefined "extreme"  rather than observed any actual change.

Beware of adjectives when discussing science.   

   

[Bored chemist]

You have missed the key point about "extreme weather". This journaliststic term ...

Your decision to introduce journalism to the discussion of weather is, at best, unhelpful.
If you look at the weather ledgers kept over the years you will find that we are seeing records of things like temperature and rainfall that are statistically anomalous. The weather is getting more variable than it was.
That's what I mean by extreme weather.
It's documented and real, and scientific.

So, like I said, the locations of fisherman's houses have absolutely nothing to do with the issue and you should be ashamed of yourself for introducing them, then trying to defend doing so.
(Please don't waste time saying that -for example- if you wait long enough you will get a hotter June than any previous one. We know that, it's taken account of in the statistical analysis.)

[alancalverd]

As I as discussing "extreme weather" in response to another posting, it seemed entirely sensible to point out that it is a journalistic term with no scientific definition.

I wonder what you mean by "the weather is getting more variable"? Snow is now very rare in England, we haven't had a decent hurricane for a very long time, and the highest temperature ever recorded was in 2003 - other monthly records are much older:   http://www.torro.org.uk/maxtemps.php.
This reduced variability is to be expected as the climate generally gets warmer.

http://www.nhc.noaa.gov/pastdec.shtml shows that US hurricane strikes have decreased during the last 50 years, but maybe NOAA are a bunch of liars paid by the oil industry. The difference is that the amount of damage done by each hurricane has increased, for the reasons I pointed out with no hint of shame because I not ashamed of facts, just intrigued by them.

I'm slightly baffled by your assertion that we are seeing statistical anomalies, contradicted by your later advice that I shouldn't waste your time by pointing out statistical anomalies. 

[Bored chemist]

Snow is now very rare in England,
...
we haven't had a decent hurricane for a very long time,

It is snowing outside my window as I type this. It has snowed on about half the days in the last week,
It's true that we don't get many tropical storms in the UK.
I wonder if anyone  can suggest a reason for that.

However, what your last post says- in essence- is that the weather has changed.
I agree- and, given that we have changed a significant factor in what determines the weather, it's reasonable to say that we are responsible for some of those changes in weather patterns.

Incidentally, I'm sorry to see that you didn't understand what I asked you not to waste time with, perhaps you should read it a couple more times. (Hint I'm not asking you to discount anomalies).

[alancalverd]

The U.S. Historical Climatology Network (USHCN) data are used to quantify national- and regional-scale temperature changes in the contiguous United States (CONUS). It's worth looking at the "adjustment" figures that NOAA have applied to historic data, and asking whether someone might just be massaging the data to fit the hypothesis. 

If you start by insisting that we are responsible for climate change, and "adjust" your data to reflect that hypothesis, you can end up believing it. That is propaganda, not science.

[alancalverd]

Ther is indeed half an inch of snow on the ground in Cambridge this morning. It is forecast to clear by tomorrow. In the 1960s we regularly had a foot of snow around here in January, and it often persisted into March. British weather is a very sensitive measure of climate change because the winter mean tempeature is close to zero, so a small change in either direction makes a huge difference to the snow cover.

The question here is whether  a foot of snow is an "extreme" phenomenon. Since it only equates to about a quarter inch of rain, it isn't scientifically extreme, but it can cause a huge amount of disruption to transport if you aren't prepared for it, so it's socially significant and makes headlines.   

I'm not relying on a fading memory, but looking at the thickness of dust on my crosscountry skis. I often skied to work and around the suburban  parks at lunchtime in the 1970s, but they haven't been used since 1980.

Falling snow in June is not uncommon, but a warming climate raises the freezing level to the point that the sky clouds over and reduces convection before it can produce the necessary towering cumulus clouds, so another "extreme phenomenon" has decreased in my lifetime.

[Bored chemist]

I'm not relying on a fading memory, but looking at the thickness of dust on my crosscountry skis. I often skied to work and around the suburban  parks at lunchtime in the 1970s, but they haven't been used since 1980.

Glad to hear it.
http://draughtyoldfentales.blogspot.co.uk/2009/02/stop-press-breaking-news-shock-horror.html
http://www.alamy.com/stock-photo-bicycles-outside-kings-college-cambridge-in-the-snow-12863597.html

It seems you could have skied more recently but didn't: so what?

[alancalverd]

The photos  were taken 8 and 10 years ago, and show not quite enough loose snow to even make a footprint. You need a good inch of packed snow  to ski safely.

Whilst the article has a ring of truth, that driving in falling snow or on loose snow is dangerous, the stuff that falls from a cold sky onto a warm pavement rarely lasts a day. You need several days of sub-zero surface air temperature followed by a good day's snowfall to make any sort of lasting impression. The Norwegians say "three falls before it lies", and that rarely happens in England nowadays.

[syhprum]

I am surprised the weight that some correspondents give to the small amount of heat given of by the burning of fossil fuels (2TW)which is infinitesimal compared to the amount we receive from the sun or even to the amount given of by the Earths radioactivity.

[Bored chemist]

The photos  were taken 8 and 10 years ago, and show not quite enough loose snow to even make a footprint. You need a good inch of packed snow  to ski safely.

Whilst the article has a ring of truth, that driving in falling snow or on loose snow is dangerous, the stuff that falls from a cold sky onto a warm pavement rarely lasts a day. You need several days of sub-zero surface air temperature followed by a good day's snowfall to make any sort of lasting impression. The Norwegians say "three falls before it lies", and that rarely happens in England nowadays.

Ok, so the weather has changed: it snows less than it used to.
We also know that we did something which affects heat transfer through the atmosphere- we added rather a lot of CO2 to it.

Is it reasonable to contend that the two facts are related?

[Tim the Plumber]

I am surprised the weight that some correspondents give to the small amount of heat given of by the burning of fossil fuels (2TW)which is infinitesimal compared to the amount we receive from the sun or even to the amount given of by the Earths radioactivity.

The argument s that CO2 causes IR to be absorbed and then emitted back to the surface whilst allowing the higher frequency sunshine to pass through.

The degree to which this is true is debated. Water vapor may well be doing all of it already except in extremely dry places.

The next argument the warmists have is that the warming from the CO2 thing will cause a massive positive feedback effect which will amplify this warming about 4 times.

I don't know if this is a reasonable position. Seems wrong to me but it is beyond my science.

The next idea is that the over all, after all the multipliers, warming of +3.4c over now will cause massive problems. This I do understand and know to be wrong.

The biggest problem they point to is the raising of sea levels due to ice melt. The ice we have is almost all safe from such a warming as it is at high altitude and very cold in Greenland and Antarctica. The edges of Greenland will melt back a bit but over all not so you will notice in terms of sea level.

However, using their inflated figures I still see no problem. Building a 1m high sea defence is not tricky. Bangladesh gets 2cm of sediment deposited every monsoon so it will be bigger in 100 years not smaller.

[alancalverd]

Ok, so the weather has changed: it snows less than it used to.
We also know that we did something which affects heat transfer through the atmosphere- we added rather a lot of CO2 to it.

Is it reasonable to contend that the two facts are related?

Almost. Except for a few facts.

1. There is a 30% discrepancy between the amount of CO2 generated from fossil fuels and other human activity, and the amount present in the atmosphere. Something else is adding it.

2. Historically, CO2 levels follow the temperature curve, they don't lead it. You can see the same behavior in the Mauna Loa data: CO2 peaks in early summer, when temperature is high but anthropogenic emission is low. The reason is obvious to biologists but not to climate "scientists".

3. The CO2 IR absorption bands in the atmosphere are saturated at about 300 ppm so adding more doesn't make a difference

4. The invisible elephant in the room is water. We know it dominates heat transfer by all possible mechanisms, by orders of magnitude, and has a positive feedback characteristic at low atmospheric concentrations, and an inverse positive feedback as surface snow and ice, but we have no idea of how much there is, where it is, or how heat is distributed in most of the oceans.

The scientific response to these facts is to consider CO2 to be an effect rather than a cause of  global surface temperature.  The correlation is obvious, but the causation is complicated.

[Bored chemist]

Ok, so the weather has changed: it snows less than it used to.
We also know that we did something which affects heat transfer through the atmosphere- we added rather a lot of CO2 to it.

Is it reasonable to contend that the two facts are related?

Almost. Except for a few facts.

1. There is a 30% discrepancy between the amount of CO2 generated from fossil fuels and other human activity, and the amount present in the atmosphere. Something else is adding it.

2. Historically, CO2 levels follow the temperature curve, they don't lead it. You can see the same behavior in the Mauna Loa data: CO2 peaks in early summer, when temperature is high but anthropogenic emission is low. The reason is obvious to biologists but not to climate "scientists".

3. The CO2 IR absorption bands in the atmosphere are saturated at about 300 ppm so adding more doesn't make a difference

4. The invisible elephant in the room is water. We know it dominates heat transfer by all possible mechanisms, by orders of magnitude, and has a positive feedback characteristic at low atmospheric concentrations, and an inverse positive feedback as surface snow and ice, but we have no idea of how much there is, where it is, or how heat is distributed in most of the oceans.

The scientific response to these facts is to consider CO2 to be an effect rather than a cause of  global surface temperature.  The correlation is obvious, but the causation is complicated.

OK, lets start by asking what the error margins are on that 30% but, setting that aside for the moment, you accept that most of the additional CO2 is down to us.

3 just isn't true (and I suspect only one of us is actually a spectroscopist)

4 The water isn't invisible- it's invariant.

With 2/3 of the earth's surface covered by water, the amount of water in the air depends on local temperature.  (hint- if there's more than can be accommodated- it rains)

Now you have two choices here- you can accept that the temperature is going up and then you have to explain why (and we are back to pointing the finger at CO2). Or you can say the temperature is staying the same- in which case the quantity of water in the air is staying the same.

[alancalverd]

One of us certainly isn't a meteorologist.

[puppypower]

One of us certainly isn't a meteorologist.

An interesting plot is the earth's temperature as a function of atmospheric CO2, starting before fossil fuels formed; 300 million years ago, up to the present. The atmospheric CO2 was higher before fossil fuels, with the formation of fossil fuels, fixing CO2, so it was not longer part of the atmosphere and carbon cycle.


When fossil fuels started to form, the temperature went down to about modern levels. But afterwards, with less atmospheric CO2,  there was a temperature rise, to levels slightly higher, then before fossil fuels. The graph also shows places from about 450M-375M years ago where CO2 fluctuated and temperature held steady, or from 200M to 100M where CO2 rises and temperature falls.


The impact of CO2 on temperature is not clear cut and linear, but appears to be influenced by other parameters. The computer models are all high, meaning they lack key parameters, which can moderate, amplify and even reverse the expected impact of CO2.


We currently look only at the last 100 years, where we have a nice line that appears to correlate CO2 to temperature. But in the bigger picture, this correlation did not always hold up.

[Bored chemist]

One of us certainly isn't a meteorologist.

It hardly matters if we are both gave-diggers or politicians.
The transition's not fully saturated so your claim just isn't true.

[alancalverd]

A quick google search hasn't turned up the infrared absorption coefficient for CO2, so I'm relying on the memory of other people's data. Can you produce a figure? I'd like to review the maths. AFAIK there are only two significant bands in the IR, but I don't have Landolt-Bornstein or whatever standard text you use.