APOD: Global Warming Predictions (2009 April 21)

[gpobserver]

Yes, that is a nice presentation of the evidence for astronomical influences on the history of ice ages. The periods of 23 kyr, 41 kyr, and 100 kyr certainly suggest known long-term orbital and rotational variations but the imperfect correlation indicates something else is at work that predominates.

Because of the increase in albedo of the earth when it is heavily glaciated, there is a hysteresis effect that will tend to make the climate stay cold during ice ages and warm during interglacials.

It is known that the sun is slowly becoming more luminous as it ages as a normal Main Sequence star but this cannot have any significant during the past few million years. The lesser luminosity of a young sun may perhaps have contributed to the 'Snowball Earth' glaciations prior to the Cambrian period.

Shorter term variations in solar activity as recorded by C14 and Be10 appear to be correlated with climate variations as indicated in http://elpub.wdcb.ru/journals/rjes/v09/ ... html#flon3. An article in Earth and Planetary Science Letters (as summarized at http://www.unisci.com/stories/20022/0606022.htm) discusses Be10 records indicating a 100 kyr variation in solar activity.

I still see much evidence suggesting a strong solar influence on terrestrial climate both in the short term and long term, compounded by orbital and rotational geometry, ocean circulation, etc., etc.

The terrestrial climate system is an enormously complex and chaotic system. One may construct a computer model of a two-body system moving under gravitational force and describe the motion at any time t into the future. However, models of three bodies become extremely senstive to initial starting conditions and one has little confidence of accurately describing the system in the future. I'm going to need a lot more convincing that a minor atmospheric constituent is more influential than the sun.

Best regards,
- Roy Tucker

[StACase]

Humans can easily survive a glacial period, and the natural rate such a period comes on is unlikely to cause major societal problems. There will probably be a smaller human population during a glacial period, but I don't see anything unfortunate or problematic about that.

And the other day you wrote:

The ramifications of the worse case change over the next century are completely devastating.

Seems to me you claim an ice age is no problem but "Global Warming" is "devastating".
So which way is it? I'd say your reasoning is very selective.

For the past eight years or so, the atmospheric content of CO2 (anthropogenic or otherwise) has increased but world climate has cooled.

Some people like to say that, but where is the evidence of such cooling? I look at the data:



and see no such cooling trend. (This is from NASA's Goddard Institute, and shows average and annual temperatures through 1997, the most recent year that has data available.)

GISS data is up to date through this last April. Here's where you find the data:

http://data.giss.nasa.gov/gistemp/table ... s+dSST.txt

And when you plot out the 5-Year Mean Global Temperature Change (°C) it looks like this:

There's a drop at the end of that chart. Some people do like to point that out. I like to point out that the 20 or so IPCC models didn't predict that drop, and that if they didn't predict that accurately, they aren't going to be accurate 92 years from now. See my tag line.

[Chris Peterson]

Humans can easily survive a glacial period, and the natural rate such a period comes on is unlikely to cause major societal problems. There will probably be a smaller human population during a glacial period, but I don't see anything unfortunate or problematic about that.

And the other day you wrote:

The ramifications of the worse case change over the next century are completely devastating.

Seems to me you claim an ice age is no problem but "Global Warming" is "devastating".
So which way is it? I'd say your reasoning is very selective.

And I'd say you're being deliberately obtuse. How difficult is it to understand that the problem isn't the temperature change, it's the rate of change? That has been stated many times. Three degrees over a few decades is likely to cause huge social and economic problems. Eight or ten degrees over a couple of thousand years is entirely manageable (no single society even lasts that long).

And when you plot out the 5-Year Mean Global Temperature Change (°C) it looks like this:

There's a drop at the end of that chart. Some people do like to point that out. I like to point out that the 20 or so IPCC models didn't predict that drop, and that if they didn't predict that accurately, they aren't going to be accurate 92 years from now.

All I can assume is that you're being obtuse again, because I know you are smarter than that. The curve is littered with little drops like that, none of which affect the broad, obvious, and significant upward trend. The models (which are not IPCC models) make no attempt to track such short term variation. They do, however, pretty accurately describe the upward trend, and there's no reason to think that they don't extend with reasonable accuracy for a number of decades or more into the future. No reasonable person can look at that chart and think that a tiny dip at the end means that more than a century of temperature increase is all over. What mechanism do you expect to produce a sudden cooling? None has been identified. Seriously, looking at the data over the last century, is it more reasonable to say that it's likely to get warmer in the future, cooler, or to stay the same?

[gpobserver]

I think it might be worthwhile to present this graph to give a longer view into the past than just the past century or so:

[Dr. Skeptic]

I think it might be worthwhile to present this graph to give a longer view into the past than just the past century or so:

So, what is the source of this data, is it records from one city, estimates from world wide core samples ... are we comparing apples to apples?

[gpobserver]

The graphic was from:

http://muller.lbl.gov/pages/IceAgeBook/ ... html%20old

"Data from a kilometer long core taken from the Greenland glacier, as part of the Greenland Ice Sheet Project "GISP2"

[Chris Peterson]

The graphic was from:

http://muller.lbl.gov/pages/IceAgeBook/ ... html%20old

"Data from a kilometer long core taken from the Greenland glacier, as part of the Greenland Ice Sheet Project "GISP2"

It's an interesting bit of data, and a nice example of the sort of data that is available, but in terms of global climate, what can a single proxy like this tell us? Very little, I think, about global average temperatures.

As the author of the book says about this graphic,

"So we can’t easily interpret everything in these plots, at least not without studying other records. Fluctuations are evident all over the plot, and crying to be understood."

[gpobserver]

Ok, how about http://www.ncdc.noaa.gov/paleo/metadata ... -8410.html?

[Chris Peterson]

Ok, how about http://www.ncdc.noaa.gov/paleo/metadata ... -8410.html?

Well, yeah, that's just the sort of data I'd be wanting to use if I were a climate researcher. <g>

[BMAONE23]

Here is an interesting image of current northern hemisphere ice levels. This is the first time, that I can find in recently historical data and images, that the western coast of Greenland has been mostly ice free in May.

The eastern coast is also beginning to break up early, and the northern coast is thinning in areas. This year, Greenland may become Sea Ice Free. If this happens, the coastal glaciers and inland ice sheet will be free to shift faster than ever.

[gpobserver]

Well, that was interesting. I randomly selected 16 of the temperature chronologies at ftp://ftp.ncdc.noaa.gov/pub/data/paleo/ ... recons.txt and spent some time plotting with Excel. The plots varied considerably with regard to temporal resolution and short-term variations but generally one could recognize the Medieval Warm Period, the Little Ice Age, and that 0 AD was warmer than the present time. Now, I'll dig up some Be-10 data and see how that compares with the plots.

[gpobserver]

There's a portion of a book chapter on Be-10 excerpted at http://www.onafarawayday.com/Radiogenic/Ch14/Ch14-3.htm that was very helpful. As expected, it provides a good record, along with C-14, of solar activity. There is clear correlation with the Maunder Minimum.

[BMAONE23]

There's a portion of a book chapter on Be-10 excerpted at http://www.onafarawayday.com/Radiogenic/Ch14/Ch14-3.htm that was very helpful. As expected, it provides a good record, along with C-14, of solar activity. There is clear correlation with the Maunder Minimum.

Is there also good correlation with at least 10 other minimums and maximums or non-cyclical cooling periods?
If the correlation between Maunder Minimum and Little Ice Age is the driving factor, then most all other historic minimums and maximums should alsy be reflected in temperatures.

[gpobserver]

Nice graphic of recent temps and CO2:

[BMAONE23]

But, what has previously been pointed out in this and other discussions concerning global climate, a few years downturn is not reflective in "Climate" changes. It is only indicative of weather trends. According to your chart, the period between 2002 and 2007 saw a net increase in temperature of .11c. The downturn in temperature has only been since 2007. The year of 2007 saw a temperature drop of .7c but from 2008 to 2009 the temperature has rebounded by .18c If you look back at the 50 year trend (more climate pattern trend than weather induced fluctuation) you will see a different story than that shown by your limiting graph


Or this one from WIKI

[StACase]

The models (which are not IPCC models)

Point taken, the IPCC Assessment reports merely reference them over and over and over and over again.

make no attempt to track such short term variation.

I don't consider eight years short term

They do, however, pretty accurately describe the upward trend,

No they don't. They all overestimated warming so far.

and there's no reason to think that they don't extend with reasonable accuracy for a number of decades or more into the future.

They are on course to miss the target by a wide margin.

No reasonable person can look at that chart and think that a tiny dip at the end means that more than a century of temperature increase is all over.

No reasonable person should expect a winning streak in a craps game to continue. That chart could be a function of random variation. I can easily write an Excel spread sheet that generates random numbers and produces graphs that look very similar to those world average temperature graphs.

What mechanism do you expect to produce a sudden cooling? None has been identified.

Someone posted this graphic:

What caused the 1840 - 1860 cooling? The 1880 - 1915 Cooling? the 1945 - 1975 cooling?
Whatever mechanisms caused those is the answer to your question. No one expects climate to stay the same. That temperature has gone up 0.7°C in 120 years should not be surprising or a great matter of concern. However people like you claiming ramifications of the worse case change over the next century are completely devastating. encourage politicians to seize the issue for their own ends.

Seriously, looking at the data over the last century, is it more reasonable to say that it's likely to get warmer in the future, cooler, or to stay the same?

You're right, the smart money would be on a continuing trend, but I wouldn't bet the farm on it. But that's what the politicians who are in charge seem to want to do.

[dduggan47]

You're right, the smart money would be on a continuing trend, but I wouldn't bet the farm on it. But that's what the politicians who are in charge seem to want to do.

Doing nothing is betting the farm.

Taking preventative action (as "the politicians who are in charge seem to want to do") is more like hedging your bet, it allows you to survive either way.

[Chris Peterson]

You're right, the smart money would be on a continuing trend, but I wouldn't bet the farm on it. But that's what the politicians who are in charge seem to want to do.

Well you see, that's where we differ on the policy issue. I see the actions: high carbon tax, development of renewable energy sources, elimination of petroleum-based energy, etc as things that are required for a strong economy. These things would be beneficial even without global warming.

[gpobserver]

BMAONE23 wrote:

"But, what has previously been pointed out in this and other discussions concerning global climate, a few years downturn is not reflective in "Climate" changes. It is only indicative of weather trends. According to your chart, the period between 2002 and 2007 saw a net increase in temperature of .11c. The downturn in temperature has only been since 2007. The year of 2007 saw a temperature drop of .7c but from 2008 to 2009 the temperature has rebounded by .18c If you look back at the 50 year trend (more climate pattern trend than weather induced fluctuation) you will see a different story than that shown by your limiting graph"

You present data from the U.S. National Surface Temperature data set. If you will examine the presentation at http://www.surfacestations.org/, you will see that the quality of the data is not as good as would be desired. A majority of the recording stations do not meet the published requirements and are seriously influenced by things such as blacktop parking lots, air conditioning compressors, shingled rooftops, etc. I would urge you to use that dataset with caution. The graphic I used was from satellite data which does not suffer such problems and also provides a more uniform distribution of sampling of the earth, not just the US and land surfaces.

Please also note from http://en.wikipedia.org/wiki/Sunspot that there has been a trend of increasing solar activity during the 20th century. The hypothesis of solar influence on terrestrial climate is not disproven.

Let us try to determine what things we agree upon. Do you assert that solar activity has no influence on terrestrial climate? I do not assert that CO2 does not produce a warming effect. I simply disagree as to the magnitude compared to other influences. I disagree that the human contribution of CO2 has any significant influence compared to other things such as solar activity. Simply asserting that temperatures have risen as human contributions of CO2 have risen and that the correlation proves the link is insufficient. I could similarly assert that the increasing number of cell phone towers are causing warming.

[StACase]

You're right, the smart money would be on a continuing trend, but I wouldn't bet the farm on it. But that's what the politicians who are in charge seem to want to do.

Doing nothing is betting the farm.

Taking preventative action (as "the politicians who are in charge seem to want to do") is more like hedging your bet, it allows you to survive either way.

The point I failed to make in my earlier effort, concerns the trend. If you plot the trend for the Hadley data which goes back to 1850,



the overall trend is 0.7°C in almost 160 years. That's less than 0.5°C per century. That's the trend for the instrument record. Betting the farm in this case is draconian regulation of our primary source of energy, and you want to bet the farm because it might be almost 0.5°C warmer by 2100. I think that's foolish.

What's foolish is believing the IPCC projections see figure 10.20 from the IPCC AR4 which show trends anywhere from 2° to over 5.5°C by 2100. That's anywhere from 4 to over 20 times the observed rate of increase these past 160 years. Any reasonable person should see the folly in that. And as I keep pointing out, a mere 8 years into those projections, they are wrong!

So are you going to be happy when they pass the regulations telling you when where and how far you can drive your car? Where to set your thermostat? What you can eat?

[Chris Peterson]

So are you going to be happy when they pass the regulations telling you when where and how far you can drive your car? Where to set your thermostat? What you can eat?

I don't see any evidence that such regulations are necessary or likely to happen. What effective regulations will do is make it uneconomical for people to buy cars that run on carbon-based fuels (and for manufacturers to produce them). They can make carbon-based energy uncompetitive compared with renewable sources.

[Chris Peterson]

Please also note from http://en.wikipedia.org/wiki/Sunspot that there has been a trend of increasing solar activity during the 20th century. The hypothesis of solar influence on terrestrial climate is not disproven.

Nobody doubts there is solar influence on the climate. But it doesn't do a good job of explaining the recent trend. And while activity has been high at times in the last century, there's no evidence at all that the average solar output has changed, and good evidence for the last 40 years that it has not.

I do not assert that CO2 does not produce a warming effect. I simply disagree as to the magnitude compared to other influences.

That's good, because the effect is obvious. It barely needs modeling to connect the CO2 concentration to the observed warming. The biggest difficulty those who disbelieve that this is the major forcing element of the current trend have is to explain how the observed rise in CO2 concentrations could not be responsible for the observed temperatures.

[gpobserver]

Chris Peterson wrote:

"Nobody doubts there is solar influence on the climate. But it doesn't do a good job of explaining the recent trend. And while activity has been high at times in the last century, there's no evidence at all that the average solar output has changed, and good evidence for the last 40 years that it has not."

That is not correct, Sir. As I have explained before, it is not the solar irradiance that is proposed to explain the influence but the modulation of the high-energy galactic cosmic ray flux and the resultant nucleation of low-level clouds that affects the earth's albedo. The current solar activity is the lowest in a century and the cosmic ray flux is up. The cooling in the satellite data and the reduced heat content of the oceans in the past few years nicely correlates with this reduced activity. The higher temperatures of the last century also nicely correlate with a period of historically high activity and a recovery from the cold temperatures of the Maunder and Dalton minima. I do not understand why you persist in talking about solar irradiance and not about the cosmic ray flux. An examination of the Be-10 record, a cosmogenically-produced radionuclide that records cosmic ray flux, shows compelling correlation with climate fluctuations.

You wrote:

"That's good, because the effect is obvious. It barely needs modeling to connect the CO2 concentration to the observed warming. The biggest difficulty those who disbelieve that this is the major forcing element of the current trend have is to explain how the observed rise in CO2 concentrations could not be responsible for the observed temperatures."

You display more of your ignorance here, Sir. It is well known that the increase in CO2 alone is inadequate to explain the warming that is seen. It is only through proposed but unproven and unquantified 'positive feedback' mechanisms such as an increase in water vapor, a much more important GHG, that modelers try to incriminate CO2.

You wrote:

"Well you see, that's where we differ on the policy issue. I see the actions: high carbon tax, development of renewable energy sources, elimination of petroleum-based energy, etc as things that are required for a strong economy. These things would be beneficial even without global warming."

You also display your ignorance of economics. Higher taxes and expensive energy will reduce economic activity and reduce our quality of life. The renewable energy sources proposed, wind and solar, are not available in all places and at all times. Some sort of backup source of power must be maintained and ready to take up the load on short notice. Britain is learning some hard lessons about the folly of wind power. Battery-powered cars must be recharged. A modest car using the equivalent of 40 horsepower being driven 40 miles per day (assume one hour of driving in the city) will use the equivalent of 30 kwh of energy. There are 250,000,000 cars in the US. Let's assume only 50,000,000 are driven each day on the average. That means that a fleet of electric cars will use 1.5 billion kilowatt-hours of energy each day. Where's that energy going to come from? It means we'll have to build more power plants, beef up the power distribution grid, and still be burning fossil fuels. You want to build another thousand fossil-fueled electrical power plants? Or, do you support the idea of building new nuclear power plants? Instead of relatively simple engines in the cars, we'll have to mine large quantities of nickel and other materials for the batteries. More mining, more heavy metals in the environment, more waste disposal, more devastation of the environment all for the sake of making a 'green' car.

Economists show that each low-paying 'green' job is going to eliminate 1.2 real jobs, jobs that actually do create new wealth. The 'green' job concept is like trying to stimulate the economy by breaking everybody's windows. Everybody will have to pay to have the windows fixed, the glaziers will prosper and buy groceries, services, expand their businesses, and buy new glass from the glass-makers. The effect will propagate through the whole economy, supposedly enriching everyone. However, the homeowners are poorer for having to pay for new windows and the environment is now filled with broken glass and new mines for sand and other raw materials for making glass. No real new wealth has been created and, on average, everyone is poorer.

[gpobserver]

http://www.youtube.com/watch?v=teMlv3ripSM

[bystander]

http://www.youtube.com/watch?v=teMlv3ripSM

how apropos