Thanks for the link, unfortunately it requires a subscription.

In summary: AGW is the primary cause. It's really a bit of a mess:In summary, the article discusses the lack of evidence for global warming man-made or otherwise and how the cooling effect of La Nina may be contributing to this.
  • #36
The stock market and AGW is a good analogy, some one says some thing bogus in America and and world markets fall.
 
Earth sciences news on Phys.org
  • #37
vanesch said:
No, but can't we look upon this in the following way:
a serious effort to reduce CO2 emissions in the coming decades would help us find out whether or not the CO2 level in the atmosphere is human-generated and what climate impact it finally has.

In other words, the effort to reduce (after a serious rise) the CO2 emissions would be part of an experimental protocol, to see if the eventual correlation between human emissions and an eventual temperature change is actually a causal link.

In other words, the billions spend, are billions spend on an experiment. Any money spend on experiments is well-spend, I'd say, as a (lunatic) scientist :smile:
How would this settle the issue? If temperatures rose then AGW proponents would claim vindication and cry too little too late and if they fell they would also claim vindication.

The same old heads I win, tails you lose you already see from the panic merchants every day in the press such as when it rains it's because of GW and if it doesn't rain it's because of global warming but now with billions of dollars wasted. Given that historically the Earth spends most of it's time frozen I think the money would be far better spent working out how to reduce the impact of the next cold period.
 
Last edited by a moderator:
  • #38
Art said:
How would this settle the issue? If temperatures rose then AGW proponents would claim vindication and cry too little too late and if they fell they would also claim vindication.

The same old heads I win, tails you lose ...

I seem to remember that science is about falsifiability. Processing data following a hypothesis would set a prediction. Reality would either support or falsify that, with a grey area in between, of course.

If the prediction is meaningless, warming or cooling, it doesn't matter, AGW is true anyway, why can this still be called science? For instance replace AGW with "deity" and recheck the logic.
 
  • #39
1914-1918, industrial output (and carbon dioxide emissions) ~ doubled; 1929-193X, industrial output halved; 1939-1945, output doubled. Existing data on atmospheric carbon dioxide concentrations hint at reductions during the world wars, no change during the great depression. How curious. Any other factors at work? The experiments being proposed have been done.
 
  • #40
Art said:
:confused: I never argued average global temperatures don't change.
I'm sorry, I misunderstood you.

However man-made emissions of CO2 don't appear to have much if anything to do with it else why has there been no increase in global temperatures for the past 10 years?
Has there not? Well, we need to look carefully to determine if "increase in global temperatures in the last 10 years" is even a meaningful quantity.

First, to extract a trend out of data, you need to have enough data that the extracted trend is meaningful. For instance, if the mean temperature some year is 0.1K greater than the mean temperature for the previous year, one can't use these two data points and say there's been a warming trend of 10K/century. That's sounds ridiculous. Surely, 2 data points is insufficient to extract a trend. So how many data points do you need?

The condition that determines this is that the trend extracted from a data set should not change significantly by adding a small number of data points to the data set. In the above example, if we go back an extra year and find that the temperature has dropped by 0.2K since that year, it drastically changes the "trend" from +10K/cent to about -10K/cent. That's not acceptable. We need to keep including more and more data points in the data set so that additional inclusions make sufficiently small changes to the extracted slope.

Now if you look at global temperature data (from GHCN) for the last 9 years, do a linear least squares fit and extract a slope, you get a number of +3.40K/cent. That is a huge warming trend...but is it meaningful? Adding one more year (1998, which was a really warm year) to the dataset, reduces the trend to +1.94K/cent. That's still a large, positive warming trend, but the number has changed a fair bit. If you include 1997, the trend becomes +2.49K/cent. A smaller change, but still not small enough for a good estimate of the trend. The lesson here is that one can talk about temperature changes over a decade, only if one is willing to admit the kind of errors we see above.

If we approximate the noise in the global temperatures as Gaussian, then the condition to be met for "good data" is: [itex]\Delta T =sn\gg \sigma/\sqrt{n}[/itex], where [itex]\Delta T[/itex] is the change in temperature over the period spanned by the data set, s is the trend in K/yr, n is the number of years in the set and [itex]\sigma[/itex] is the RMS noise in the data. From the GHCN data, I estimated the noise to be about 0.1K. So, if you are extracting a trend which is smaller than 1K/cent (or 0.01K/yr), you need a data set with [itex]n \gg 10^{2/3} \approx 5[/itex].

One can also work backwards and determine the goodness of a data set. With n=10, s=0.0194K/yr (the numbers I get from the GHCN data for the last decade), the signal to noise ratio for the extracted temperature change is roughly given by [itex]S/N\approx (s/\sigma)n^{1.5} \approx 6[/itex]. At a 68% (1 standard deviation) confidence level the error bar on the data is just the inverse of this number, or about [itex]\pm 15[/itex]%, which is not great, but not completely terrible either. Naturally, if you want a greater confidence in the data, the error bar increases.

So, at this confidence level, we can say that the increase in the global mean temperature over the last decade, according to GHCN data is [itex]0.19K \pm 0.03K[/itex]. That trend is significantly larger than the trend for the 21st century, which I think is about 0.5K/cent. So I'd say, with a fairly high confidence, that based on GHCN data, the global temperatures over the last decade have not only been rising, but have been rising significantly faster than the average over the last century.


For AGW to be true then isn't a rise in temperatures a fundamental requirement? :rolleyes:
Actually, it's not.

Evo said:
What about 2001?
Talking about a single data point is meaningless. As shown above, even a decade worth of data points is only moderately useful.


Evo said:
What about the cooling oceans that they just discovered that was a complete surprise? They said the oceans were getting warmer, but after actually testing, found they're getting colder.
I don't think that's accurate. If I'm not mistaken, sea surface temperatures have been increasing as expected, but deep sea temperatures in recent years have dropped due to the slow migration of Arctic deep waters resulting from increased melting of polar ice.

Art said:
How would this settle the issue? If temperatures rose then AGW proponents would claim vindication and cry too little too late and if they fell they would also claim vindication.
If I recall correctly, the last IPCC report included very specific predictions based on different scenarios for CO2 emissions. I think, at the very least, if we follow one of those scenarios and observe temperatures that are very different from their predictions, they will have to admit that there are flaws in their model.
 
Last edited:
  • #41
Art said:
How would this settle the issue? If temperatures rose then AGW proponents would claim vindication and cry too little too late and if they fell they would also claim vindication.

We shouldn't (and we won't) reduce our CO2 emissions too soon. Now, if the AGW claims are correct, we should see, 30-40 years from now, undisputable evidence for a serious rise in temperature which will not be on the limit of the noise, or on too short time scales to be noticeable. And I don't think we will reduce our CO2 emissions before that (we may temper our increase in emissions maybe). So, if 30-40 years from now, there has been a serious increase in temperature, the shores of Antarctica are now open to tourism on the beach etc... then at least part of the claim of AGW has been validated - (the GW part). But that still doesn't qualify the "A" part. If now, we REDUCE our CO2 emissions, 50-70 years from now, to, say, the level before 1950, and we wait until the end of the century, if antarctica's coasts freeze over again, and the temperature drops again by several degrees, then the "A" part will have been validated too.
The point is, if after CO2 emission reduction, the heating continues, then the A-part was wrong.

So *in any case* we (or better, our grandchildren) will find out. But it will take time.

And it would be nice to know, by then. As such, we would then be able to *choose* our climate, by putting out the right gas mixtures. So this is just an experiment in global climate engineering.
 
  • #42
Gokul43201 said:
Now if you look at global temperature data (from GHCN) for the last 9 years, do a linear least squares fit and extract a slope, you get a number of +3.40K/cent. That is a huge warming trend...but is it meaningful? Adding one more year (1998, which was a really warm year) to the dataset, reduces the trend to +1.94K/cent. That's still a large, positive warming trend, but the number has changed a fair bit. If you include 1997, the trend becomes +2.49K/cent. A smaller change, but still not small enough for a good estimate of the trend.

Indeed trends are useless due to the limited data and start/end point bias. But then again, what is global temperature? There are four major data sets monitoring "global temperature" of which the chosen one above, GISS of GHCN, happens to show the strongest warming trend 0.19 degrees per decade (d/d) as of 1979 (starting point of the satellite series). NOAA and HADCRUT (of the Hadley Met office UK) tie second place with 0.17 d/d, while the Satellite measured lower troposhere temperature (MSU2LT) is showing 0.14 d/d. If we look at the same ten years, curiously enough GHCN increased the trend slightly (0.2 d/d) whereas all others decreased, NOAA 0.13 d/d, HADCRUT 0.04 d/d and MSU2LT: 0.06 d/d. As a table:

Period:...1979-2007...1998-2007
GHCN:...0.193...0.199
NOAA:...0.170...0.127
HADCRUT:..0.170...0.041
MSU2LT...0.142...0.057

See the uploaded graph for comparison. So why are not all graphs identical? For the choice of ground stations, there is the individual bias of changing land use, sensor discontinuities, urban heat island effect, local micro climate changes, areas not covered, etc. The satellite temperature is biased by a small side band of higher level temperatures and satellite drift. Each set is supposed to be best corrected for those. Apparantly,there are some differences in assumptions.

Additional data:
ftp://ftp.ncdc.noaa.gov/pub/data/anomalies/annual.land_and_ocean.90S.90N.df_1901-2000mean.dat[/URL]
[url=http://hadobs.metoffice.com/hadcrut3/diagnostics/global/nh+sh/monthly]HADCRUT[/url]
[PLAIN]http://www.nsstc.uah.edu/data/msu/t2lt/tltglhmam_5.2

So what caused this recent uptrend, which may or may not be reversing? Remember that we try to solve a single equation with N variable forcing functions.

Apart from increasing greenhouse effect could we also take in consideration:

For the Anthropogenic -part:
- black soot
- aircraft contrail induced cirrus clouds
- direct industrial warmth and additional artificially produced water vapor affecting local sensors

For the natural part:

- Recovery from an La Nina dominated 1960s-1970s to the El Nino dominated 1980s -1990s
- Cloud albedo changes
- Reversals of the North Atlantic Oscillation
- Solar changes.
 

Attachments

  • global-temp.gif
    global-temp.gif
    22.3 KB · Views: 495
Last edited by a moderator:
  • #43
Andre said:
Indeed trends are useless due to the limited data and start/end point bias. But then again, what is global temperature? There are four major data sets monitoring "global temperature" of which the chosen one above, GISS of GHCN, happens to show the strongest warming trend 0.19 degrees per decade (d/d) as of 1979 (starting point of the satellite series). NOAA and HADCRUT (of the Hadley Met office UK) tie second place with 0.17 d/d, while the Satellite measured lower troposhere temperature (MSU2LT) is showing 0.14 d/d. If we look at the same ten years, curiously enough GHCN increased the trend slightly (0.2 d/d) whereas all others decreased, NOAA 0.13 d/d, HADCRUT 0.04 d/d and MSU2LT: 0.06 d/d. As a table:

Period:...1979-2007...1998-2007
GHCN:...0.193...0.199
NOAA:...0.170...0.127
HADCRUT:..0.170...0.041
MSU2LT...0.142...0.057
For this level of discrimination, it doesn't look like we get enough S/N from just a single decade of data. It appears that HADCRUT and MSU2LT decadal trend numbers are lower primarily due to the increased anomaly in 1998 for those two sets compared to the other 2. I wonder if the numbers will not all look much closer if you extend the set down to say 1996, or if you start at 1999, instead of starting at the highly anomalous 1998 (strong El Nino year).

See the uploaded graph for comparison. So why are not all graphs identical? For the choice of ground stations, there is the individual bias of changing land use, sensor discontinuities, urban heat island effect, local micro climate changes, areas not covered, etc. The satellite temperature is biased by a small side band of higher level temperatures and satellite drift. Each set is supposed to be best corrected for those. Apparantly,there are some differences in assumptions.
I'm not very familiar with all the pros and cons of the different measurements. But it is at least a little encouraging that over the 18 year period, all data sets agree to about a 60% confidence level, and the first 3 out of the 4 sets agree to better than a 95% confidence level. How well do HADCRUT and MSU2LT agree with GHCN over longer periods?

Additional data:
ftp://ftp.ncdc.noaa.gov/pub/data/anomalies/annual.land_and_ocean.90S.90N.df_1901-2000mean.dat[/URL]
[url=http://hadobs.metoffice.com/hadcrut3/diagnostics/global/nh+sh/monthly]HADCRUT[/url]
[PLAIN]http://www.nsstc.uah.edu/data/msu/t2lt/tltglhmam_5.2

So what caused this recent uptrend, which may or may not be reversing?
Do you mean downtrend or uptrend? I'm not sure which change you are talking about. It looks to me like any "change" is not real, and is mostly an artifact of a small dataset with a slope dominated by end-point selection.

Remember that we try to solve a single equation with N variable forcing functions.

Apart from increasing greenhouse effect could we also take in consideration:

For the Anthropogenic -part:
- black soot
- aircraft contrail induced cirrus clouds
- direct industrial warmth and additional artificially produced water vapor affecting local sensors

For the natural part:

- Recovery from an La Nina dominated 1960s-1970s to the El Nino dominated 1980s -1990s
- Cloud albedo changes
- Reversals of the North Atlantic Oscillation
- Solar changes.
In my opinion, the biggest reason for the "downtrend" seen in the bottom 3 measurements in your table is the 97-98 El Nino event.

PS: If you eliminate 1998 from the datasets, and start at 1997, the 4 measurements show trends that are roughly (just eyeballing it):

Period:...1997-2007 (-1998)
GHCN:....0.30
NOAA:....0.22
HADCRUT:...0.20
MSU2LT:...0.25
 
Last edited by a moderator:
  • #44
Andre: This is why I was referring to metrology in my post above. At least some of the problems with the data is simply due calibration errors and non-standardized data analysis. The variations in the data are so small that even small errors in calibration can cause alls sorts of problems. A good example is the revelation a year or so ago that the reason why satellite data for the temperature in the upped atmosphere did not agree with models (or indeed data from other sources) was due to a measurement error (as far as I remember the error was due to ice buildup on the sensor), once the error had been calibrated away the various data sets agreed (I think there was even a paper in Nature about this)

The problem is that comparing various methods for gathering data is VERY complicated and is in itself a complex metrological problem (calibration in remote sensing is actually quite problematic whatever the application) and the traceability of measurement data is a very serious issue.
 
  • #45
I just read the paper cited in the blog from the OP - thanks Evo, MB. Has anyone else read it yet?

There's nothing in the paper that disputes an anthropogenic contribution to the warming trend of the 21st century. All it says is that there is little direct correlation between CO2 levels and the extracted oscillations. It makes no claim about whether or not the CO2 concentration is correlated with the long-term trend.

And after a quick read, I've already got a problem with the results of their analysis. The span of the data set is 120 years, and they extract a 60-yr oscillation? And I don't see a single word of caution about bravely extracting a period that gives, at best, 2 oscillations. If this was Physical Review, there's no way they could have gotten away with as strong a claim as they have.

PS: I followed one of the references - Schlesinger & Ramankutty, Nature 367, 723 - 726 (1994). S & R were the first to find a 65-70 year oscillation in global temperatures, and their data set also spans about 110 years, but they state explicitly that since there are only about 2 periods worth of data, the extracted periodicity must be considered as only "provisional" until it can be applied to a larger data set. Zhen-Shan & Xian, use essentially the same data set, but do not make any such disclaimer. Moreover, S & R claim the 60 year cycle is consistent with existing models. Since I'm not aware of the state of the science in this field I don't have an appreciation for what all the hullabaloo is about.

http://www.nature.com/nature/journal/v367/n6465/abs/367723a0.html
 
Last edited:
  • #46
Gokul,

Your points are well taken, but mind that you are exposing the scientific level of climatology in general. Seeing some major accidents in other climate issues, it's clear that climatologists should be physisists first and statisticians second. Clearly this is not the case.

Furthermore about correlations of temperature series in the former post, I'd first like to illustrate how two independent agencies, monitoring the lower troposphere get to these results:

http://gallery.myff.org/gallery/241264/sat-temp2.GIF

(also uploaded)

which would suggest a more robust, reliable method than managing the problems with the ground stations.

Another question of course is, what is going on? If the current dip is La Niña or lack of sun spots and 1998 was a strong El Nino and/or solar activity, what is left for the greenhouse effect of the increasing CO2?

Data:
ftp://ftp.ssmi.com/msu/monthly_time_series/rss_monthly_msu_amsu_channel_tmt_anomalies_land_and_ocean_v03_0.txt[/URL]

[PLAIN]http://www.nsstc.uah.edu/data/msu/t2lt/tltglhmam_5.2
 

Attachments

  • sat-temp2.GIF
    sat-temp2.GIF
    18.3 KB · Views: 418
Last edited by a moderator:
  • #47
http://www.oism.org/pproject/s33p36.htm

A review of the research literature concerning the environmental consequences of increased levels of atmospheric carbon dioxide leads to the conclusion that increases during the 20th and early 21st centuries have produced no deleterious effects upon Earth's weather and climate. Increased carbon dioxide has, however, markedly increased plant growth. Predictions of harmful climatic effects due to future increases in hydrocarbon use and minor greenhouse gases like CO2 do not conform to current experimental knowledge. The environmental effects of rapid expansion of the nuclear and hydrocarbon energy industries are discussed.

We urge the United States government to reject the global warming agreement that was written in Kyoto, Japan in December, 1997, and any other similar proposals. The proposed limits on greenhouse gases would harm the environment, hinder the advance of science and technology, and damage the health and welfare of mankind.

There is no convincing scientific evidence that human release of carbon dioxide, methane, or other greenhouse gasses is causing or will, in the foreseeable future, cause catastrophic heating of the Earth's atmosphere and disruption of the Earth's climate. Moreover, there is substantial scientific evidence that increases in atmospheric carbon dioxide produce many beneficial effects upon the natural plant and animal environments of the Earth.


This petition has been signed by over 19,000 American scientists.
 
Last edited:
  • #48
http://global-warming.accuweather.com/

Where is the global warming part of all this? Well, in section 9 of the pdf, Klotzbach and Gray explain that the very large increase in major hurricanes in the Atlantic basin between 1995-2007 was in their opinion primarily a result of the multi-decadal increase in the Atlantic ocean thermohaline circulation (THC) due to changes in ocean salinity and not directly related to global temperature increase.

Klotzbach and Gray feel that we should not read too much into the highly active hurricane seasons of 2004-2005. Even though the activity was unusual, it was within natural bounds of hurricane variation. The authors note that both 2006 and 2007 had slightly below-average and average activity, respectively.
 
  • #49
And what the warmers say

http://www.ucar.edu/news/releases/2006/hurricanes.shtml

Global Warming Surpassed Natural Cycles in Fueling 2005 Hurricane Season, NCAR Scientists Conclude
June 22, 2006

BOULDER—Global warming accounted for around half of the extra hurricane-fueling warmth in the waters of the tropical North Atlantic in 2005, while natural cycles were only a minor factor, according to a new analysis by Kevin Trenberth and Dennis Shea of the National Center for Atmospheric Research (NCAR). The study will appear in the June 27 issue of Geophysical Research Letters, published by the American Geophysical Union.
 
  • #50
Actually I put up an article a while back detailing how Hurricanes had not increased in strength but had increased in duration and overall power in total energy dispersal, which you would expect if temperatures increased, that is not up for debate; what is up for debate is of course as you say how much of that overall energy increase is attributable to AGW and GW. That article of course only talks about global warming not AGW I think, if I'm interpreting what they mean by natural correctly, if not then the man's an idiot, which seems doubtful. :smile:

I'll try and find it again, it's probably closer to what scientists believe without the spin. Honestly if you believe half the political nonsense you'd believe all scientists are idiots and know nothing about their subject except that which they were spoon fed by the IPCCFJDJSKA.

EDIT: That's weird after doing a search in P&WA and Earth Sciences I can't find my post, never mind I'll look later, brain fart probably. Or maybe it's in the Archives?
 
Last edited:
  • #51
Here is a view about the ingredients to build an hurricane.

For hurricanes to be more intense, logically those factors must be stronger. This one is interesting:

The third ingredient is that of a saturated lapse rate gradient near the center of rotation of the storm. A saturated lapse rate insures latent heat will be released at a maximum rate. Hurricanes are warm core storms. The heat hurricanes generate is from the condensation of water vapor as it convectively rises around the eye wall. The lapse rate must be unstable around the eyewall to insure rising parcels of air will continue to rise and condense water vapor.

Lapse rate is the vertical decrease of temperature with height. If that decrease is small, warming uplifting air (convecting) will cool adiabatically quicker than the lapse rate and the uplift stops. The air is stable. If the lapse rate is large, the adiabatic cooling uplifting air will remain warmer (and lighter) than the envirnoment and continue to lift up. The air is unstable.

However, increased greenhouse effect is also supposed to warm the atmosphere as it agitates the increased amount of CO2 molecules. This would reduce the lapse rate and weaken this factor for hurricane forming. Therefore it's not automatically logical that more greenhouse effect would increase the strenght of the hurricanes.
 
  • #52
Last edited by a moderator:
  • #53
mheslep said:
Its coming down already in the US, 1.8% in 2006
http://www.epa.gov/climatechange/emissions/downloads/08_ES.pdf, Table ES-2
-Apparently due fossil fuel price increases and reductions in US manufacturing.

A similar decrease was observed from 2000-2001. This is within the fluctuations. The data seem compatible with a constant emission level since about 2000.

Point is, the US has an extremely bad emission profile per GDP
http://en.wikipedia.org/wiki/List_of_countries_by_ratio_of_GDP_to_carbon_dioxide_emissions

Compared to most European countries for instance, they don't do very well. So it shouldn't be difficult to improve at least a little bit there. But the biggest growth is in China:
http://www.ens-newswire.com/ens/mar2008/2008-03-11-01.asp

The researchers' most conservative forecast predicts that by 2010, there will be an increase of 600 million metric tons of carbon emissions in China over the country's levels in 2000. This growth from China alone would dramatically overshadow the 116 million metric tons of carbon emissions reductions pledged by all the developed countries in the Kyoto Protocol.

The protocol was never ratified in the United States, which was the largest single emitter of carbon dioxide until 2006, when China became the largest emitter.
2-5 % increase estimated per year, and observed: 11% per year...

So I think it is a safe bet that the global emissions are not going to decrease over the coming years, or even decades.
 
Last edited by a moderator:
  • #54
It's off topic but an immediate drastic reduction of emission is attainable by stopping heating houses electrically. It's a big big waste. I estimate that for every pound of fuel (gas oil, whatever) burned directly in your house to warm, the electrical power plant has to burn about 4 - 5 lbs. The biggest losses are the limited effectiveness of engines driving generators and the distribution through the power line net
 
  • #55
Andre said:
It's off topic but an immediate drastic reduction of emission is attainable by stopping heating houses electrically. It's a big big waste. I estimate that for every pound of fuel (gas oil, whatever) burned directly in your house to warm, the electrical power plant has to burn about 4 - 5 lbs. The biggest losses are the limited effectiveness of engines driving generators and the distribution through the power line net

Well, if the electricity comes from fossil fuel burning, of course. If it comes from a no-CO2 source (nuclear, or wind/hydro/solar/biofuel...) then it is a good idea of course. Finally, using an electrically driven heat pump is beneficial normally, even in the case of fossil fuel burning electricity, because the temperature difference of the heat cycle in the power plant is bigger than the temperature difference for the heat pump, so you should, thermodynamically win there.

But of course, in all these considerations, one has to find out how much CO2 equivalent one is gaining for what investment. Usually one considers that $ 25 is about the maximum sensible investment per ton of CO2 exhaust gained.

BTW, this was one of those optimistic stories 5 years back:
http://www.planetark.org/dailynewsstory.cfm/newsid/20921/story.htm
 
Last edited:
  • #56
vanesch said:
A similar decrease was observed from 2000-2001. This is within the fluctuations. The data seem compatible with a constant emission level since about 2000.
Perhaps, but there's a known correlation with economic growth and the US economy tanked in '01. Constant US emissions is a big change from the previous decade. DOE credits:
favorable weather conditions; higher energy prices; a decline in the carbon intensity of electric power generation that resulted from increased use of natural gas, the least carbon-intensive fossil fuel; and greater reliance on non-fossil energy sources.
for the '06 decrease.

Point is, the US has an extremely bad emission profile per GDP
http://en.wikipedia.org/wiki/List_of_countries_by_ratio_of_GDP_to_carbon_dioxide_emissions

Compared to most European countries for instance, they don't do very well. So it shouldn't be difficult to improve at least a little bit there.
Yes I wonder how much of that could be credited to the freezing more nuclear power in the US just when it started booming elsewhere. In any case, recently emissions per GDP are improving dramatically in the US, 10% better from '02 to '06.
http://www.eia.doe.gov/oiaf/1605/ggrpt/
Table 2.
 
Last edited by a moderator:
  • #57
Not really, the same happened in most European countries except France, disdaining Chernobyl "catastrophe" groupthink. Nowadays the French are ROFL whilst exporting their excess energy to other European countries, which are desperately training to cut emissions.

Therefore in most countries here, power plants run on coal. oil and natural gas, validating the electric heating waste.
 
Last edited:
  • #58
mheslep said:
Yes I wonder how much of that could be credited to the freezing more nuclear power in the US just when it started booming elsewhere. In any case, recently emissions per GDP are improving dramatically in the US, 10% better from '02 to '06.

I think nuclear power is stable for the moment in Europe, and probably on the decline unless (silly) recent political decisions (Germany, Belgium) to phase out nuclear power are overturned.

I guess the "improvement" of CO2 / GDP in the US is mainly due to non-industrial creation of wealth, which increases GDP, but doesn't change anything to CO2 exhaust. Although the CO2/GDP ratio is a good indicator of the relative efficiency of the economy wrt. CO2 when comparing countries of very different wealth, I think it is an indicator which has its limits, especially when looking at countries that have special wealth ressources, like Switzerland (banks) or Norway (foil!). However, notice the favorable scores by France and Sweden.

But it does make sense in comparing, say, the US to Europe or to India or to China. It gives an idea what to expect when those parts of the world will reach the standards of living in the west.
 
  • #59
Andre said:
I seem to remember that science is about falsifiability. Processing data following a hypothesis would set a prediction...
Agreed. This and the mention of other Goddard work up thread gives me chance to discuss "[url[/URL], [I]Global Climate Changes as Forecast by Goddard Institute for Space Studies Three Dimensional Model[/I]

There is a load of detritus surrounding a Google search on this prediction paper; perhaps some clarity has come up in depth on PF, if so sorry I looked and didn't find it, though references to Hansen himself surface often. P. Michaels has attacked the paper in a Congressional hearing; was dismissed for not citing the 'right' prediction. That is, Hansen et al offer three scenarios based on various emissions levels; scenario A over predicted 2000 temperatures by 2-3x depending on which temperature observation is selected, and scenarios B,C were fairly close. Michaels was attacked for omitting B,C. Hansen et al '88 Section 4, "Radiative Forcing in Scenarios A, B, and C" describes the assumptions:
A: "the assumed annual growth averages about [B]1.5% of current emissions[/B], so the net greenhouse forcing increases exponentially"
B: "decreasing trace gas growth rates, such that the annual increase of the greenhouse climate forcing remains approximately constant at the present level"
C: drastic reduction in GH gas growth.
with more detail given in appendix B witch list assumptions on other GH gasses as well.

Now, CO2 emissions increased [PLAIN]http://http://www.mnp.nl/en/dossiers/Climatechange/TrendGHGemissions1990-2004.html" in the 14 year period '90 through '04, with an notable 5% increase of CO2 in '04. Thus Hansen et al's scenario A is indeed the correct assumption based on CO2 emissions. There are other Hansen assumptions about volcanic insertios of aerosols to retard solar forcing; they apparently included an event in B/C and not A. I have to look more at that I don't see a chance Hansen recovers scenario A from Pinatubo; appears to me Hansen must fail by a wide margin for its first ~15 years of prediction.

Hansen et al original 1988 Figure 3 predictions updated w/ current observations:
http://www.realclimate.org/00fig1.gif
 
Last edited by a moderator:
  • #60
Hansen et al follow up in PNAS '98
"http://www.pnas.org/cgi/reprint/95/8/4113?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=1&author1=hansen&andorexacttitle=and&andorexacttitleabs=and&andorexactfulltext=and&searchid=1&FIRSTINDEX=0&sortspec=relevance&resourcetype=HWCIT"". States here why they were wrong:
The CO2 growth rate increased rapidly until the late 1970s,
more than doubling in 15 years (Fig. 6A). But the growth rate
has been flat in the past 20 years, despite moderate continued
growth of fossil fuel use and a widespread perception, albeit
unquantified, that the rate of deforestation has also increased.
Apparently the rate of uptake by CO2 sinks, either the ocean,
or, more likely, forests and soils, has increased.


And a direct answer to Michaels in '06:
Hansen et al answer in PNAS '06
"Global Temperature Change"
http://www.pnas.org/cgi/reprint/103/39/14288
Real-world GHG climate forcing (17) so far has followed a
course closest to scenario B. The real world even had one large
volcanic eruption in the 1990s, Mount Pinatubo in 1991, whereas
scenario B placed a volcano in 1995.
I don't see the basis for this statement.
 
Last edited by a moderator:
  • #61
Last edited:
  • #62
wolram said:
I have been reading this page and quite honestly i have a headache trying to sort out who is right.

http://www.john-daly.com/index.htm

STILL WAITING FOR GREENHOUSE.

Same with this thread. :wink::smile:

Both sides have very valid points the trouble is neither side is 100% sure.

Is John L. Daly André's real name. :-p
 
  • #63
John Daly deceased in 2004. His son is maintaining the webside. He was a great pioneer, daring to challenge believe, practically on is his own, alone, don't even think EXXON. And isn't that what science is all about? Facts and figures, not gut feeling?
 
Last edited:
  • #65
But there is also this.
 
  • #66
Or http://www.theonion.com/content/node/48972".
 
Last edited by a moderator:
  • #67
The Onion? Is that peer reviewed or satire?
 
  • #68
Andre said:
The Onion? Is that peer reviewed or satire?

Very dry satire

Here's a very good poke by them at victim statistics.

Millions and Millions
http://www.theonion.com/content/node/29456
 
  • #69
Andre said:
The Onion? Is that peer reviewed or satire?

I'd say it is peer reviewed at least. :smile: Satire, well obviously :smile:
 

Similar threads

Back
Top