Scientists agree ... Consensus on Global Warming
POSTED BY: Ghoulman
UPDATED: Friday, February 10, 2006 11:42
VIEWED: 22755
PAGE 12 of 21
The problem with Finn is that he thinks if he says something often enough, people will mistake it for facts. So, now for some real scientific data from Woods Hole Research Group, with url reference:
http://www.whrc.org/resources/online_publications/warming_earth/scient
ific_evidence.htm
Scientific Evidence
One can also observe that the concentration of carbon dioxide in the atmosphere and the mean annual global temperature have been increasing since the end of the last ice age approximately 10,000 years ago. Why then are the most recent increases of such concern? First, because the most recent increases are occurring at rates that have not been observed since the last ice age and have only previously been observed in association with dramatic shifts in climate. Second, the dramatic increase in carbon dioxide concentration in the atmosphere over the past 150 years (from about 280 parts per million to about 360 parts per million) is largely due to anthropogenic (human-caused) effects.
As predicted by the reports of the IPCC, the climate has indeed been changing. The ten hottest years in the period of accurate instrumental data (since the late 1800s) have all occurred since 1989. The warmest year was 1998, followed by 2002 and 2003 (tied), 2001, 1997, 1995, 1990 & 1999 (tied) and 1991 & 2000 (tied).
The temperature data for 1998 are staggering. Data collected by NOAA (National Oceanic and Atmospheric Administration) indicate that 1998 was by far the warmest year in recorded history. Global mean surface temperature in 1998 was 0.66 °C (1.20 °F) above the long-term (1880-1997) average value of 13.8 °C (56.9 °F). It is very possible for a particular year to be the warmest year on record and not be warmest on record for any single month. However, for 9 of the 12 months of 1998 the global average temperature has exceeded the monthly records for all previously recorded years. In other words, in the 100+ years that temperature data have been recorded, there has never been a warmer January, February, March, April, or May, June, July, August or October than in 1998. In addition, it's worth noting that the previous monthly records had all been established within the last ten years - between 1988 and 1997.
While the concentrations of almost all greenhouse gases have been increasing since the Industrial Revolution, carbon dioxide has had the greatest effect on changing the climate. During the 1980's humans released 5.5 billion tons of carbon dioxide into the atmosphere annually by burning fossil fuels (coal, oil, natural gas) for heat, transportation, and electricity. An additional 1.6 billion tons was released from anthropogenic (human-induced) changes in land-use (i.e. clearing land for agriculture, pastures, etc.) mostly through deforestation in the tropics.
Where does that 7.2 billion tons of atmospheric carbon go? Ocean modelers find that the ocean takes up approximately 2 billion tons a year. Around 2 billion tons are taken up by a presently unidentified "sink" or reservoir of carbon (see The Missing Carbon Sink).A paper identifying temperate soils as the missing carbon sink was published within the last few weeks. Rue This leaves a remainder of 3.2 billion tons of CO2, and global atmospheric measurements indicate that this amount is simply being added to existing concentrations already present in the atmosphere. The result is that the atmospheric concentration of carbon dioxide is increasing at a rate of approximately 1.5 ppm (parts per million) per year and overall it has increased about 30% since the beginning of the Industrial Revolution.
And the website has dramatic graphs which show breakout CO2 and temperature increases, as well as other equally dramatic graphics over time periods ranging from 150,000 to 100 years. Anyway, you get the idea. Just 'cause Finn says it's so, don't make it so.
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Quote:Absolutely right. And just because you, or the WHRC, or the IPCC says so doesn't make it so either. That has been my point all along. People need to weigh all arguments against the rigors of scientific methodology. We all need to draw conclusions from the evidence rather than from the word of "authorities," even if that word in found in a peer-reviewed journal. (I've seen a lot of crap in peer-reviewed journals. The articles are only as good as the standards of those "peers.") This sort of critical thinking doesn't require that we become experts in the field--it only requires that we understand scientific and statistical reasoning in order to become astute consumers of research.
Originally posted by rue:
Just 'cause Finn says it's so, don't make it so.
--"There are 3 types of lies: lies, damn lies, and statistics.-- attributed to Mark Twain
Can't Take My Gorram Sky
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Quote:True. But the evidence speaks for itself.
Originally posted by rue:
And the website has dramatic graphs which show breakout CO2 and temperature increases, as well as other equally dramatic graphics over time periods ranging from 150,000 to 100 years. Anyway, you get the idea. Just 'cause Finn says it's so, don't make it so.
I hope everyone interested does take rue’s advice and examines the graphs this site has to offer. Examine the graph titled “Carbon Dioxide Concentrations.” This is accurate data as far as I know; collected at the Mauna Loa volcano in Hawaii (Keeling & Whorf, CDRG). Indeed it shows a rapid increase in Carbon Dioxide during the period since 1958 when data collection began. Associated with this data is (presumably) arctic ice core data from which an estimate of carbon dioxide concentration can be deemed. I have no problem with this information. It is quite accepted.
The next graph shows mean global temperature from 1860 to perhaps 2000. Once again this is quite accepted; it appears in many papers. Now compare the graphs. You’ll see that the bulk of the warming occurred between the later decades of the 19th century up to about 1940. Indeed, according to this graph the warming during that period was over 1 degree F. From the Carbon Dioxide Graph one can see that the concentration of carbon dioxide increased from 290ppm to ~300ppm. However, the warming since 1940 has been only ~0.5 degree F, but since 1940 the concentration of Carbon Dioxide has gone from ~300ppm to ~360ppm. Indeed it was at the onset of this increase in carbon dioxide that the mean global temperature experienced the first decrease in at least almost a hundred years. In other words the bulk of the warming occurred prior to the bulk of the increase in carbon dioxide.
Rue claims that the “global warming model … is making predictions which are being supported by data.” Maybe, maybe not. MAYBE we see an increase in mean global temperature due to an increase in carbon dioxide concentration. But if this were the only or even predominate mechanism involved why does the data clearly indicate that the bulk of the warming occurred BEFORE the bulk of the increase in carbon dioxide concentration?
This is simply a first order examination of the data using the simple graphs in a site that rue posted.
Later the site makes note of the collapse of Larson B ice shelf in 2002 as physical indication of a warming trend. Maybe it is. Maybe it isn’t. This is a common mantra of global warming advocates, but huge icebergs in the Antarctic are hardly unusual. According to the Encyclopedia Britannica there have been at least 2 maybe 3 icebergs as large or larger then the Larsen B ice shelf in the Antarctic since 1927, and there are reports of huge icebergs going back as far 1854. Considering the lack of exploration of the Antarctic, there very likely could have been two or three collapses the size of the Larsen B ice shelf per century for the last countless centuries. This does not constitute reliable evidence of global warming, much less anthropogenic global warming.
“One of the largest icebergs sighted was over 140 kilometres in length. This tabular iceberg was first sighted in 1927, and presumably the same iceberg was later seen in 1931, at which time it was 100 kilometres long. The largest known Antarctic iceberg was measured by the icebreaker USS Glacier in 1956; it had a length of 333 kilometres and a width of 100 kilometres.”
http://www.britannica.com/eb/article?tocId=65705
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You're right about peer-reviewed journals. That's what makes some journals like Science, Nature, BMJ etc so prestigious, and others ... not so much.
I do think understanding the science takes some level of expertise, or at least sufficient effort.
I think one needs to know the 'langauge' of the science (each one has its own) as well as how the basic tools are used and what they are good for. And one needs to make an effort to compare articles to each other. Otherwise, one is likely to be snowed by convincing, but incomplete, erroneous, or biased, claptrap.
That's why I thought the Wood's Hole website was good. They did provide links to a variety of data sources.
My position has been and continues to be: follow the data. In that we definitely agree.
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Finn,
I suppose one could try to argue 'most' global warming occurred early if one is silly enough to use the hump that maxes out in 1940 (certainly an anomalous region in global mean temperature) - look! the GMT went up 0.6 degrees before 1940 but only 0.3 degrees after! But then I could use the dip that maxes low near 1963 (the other anomalous region) to 'prove' that most global warming occured recently - only 3.5 degrees in 100 years, but a shocking 5.5 degrees in a mere 40!
You remind me of a joke we have here: first plot your graph, then chart your data.
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Facts are facts. I didn’t make it up; this is what the data says. But I guess the data can’t possibly be right if it doesn’t serve to completely support the global warming hypothesis. At least this is the position many global warming advocates seem to take. (Your previously defined 'position' would seem to be constrained by this very thing.)
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Quote:
Facts are facts. I didn’t make it up; this is what the data says.
Where I work, this is considered one of the 'sins' of science gone bad - cherry-picking your data. Hmm, sounds like WMD. Learn much from your master?
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Quote:Clearly the facts say otherwise. The data that you posted demonstrates that the bulk of the warming occurred prior to the bulk of the increase in carbon dioxide. This is a fact. You ignore it because it doesn’t suit what you want to be true. Balloon and satellite data don’t show any appreciable warming at all. This, I imagine, is also data you’ve ignored.
Originally posted by rue:Quote:
Facts are facts. I didn’t make it up; this is what the data says.
Where I work, this is considered one of the 'sins' of science gone bad - cherry-picking your data. Hmm, sounds like WMD. Learn much from your master?
According to you:
Quote:Follow the data as long as it leads you where you want it to, eh? If it doesn’t then it’s “anomalous.” Well it is anomalous. If you assume that an anthropogenic greenhouse effect is the only or predominant mechanism, then a lot of data becomes anomalous. The question is, how closely do you want to adhere to this sectarian philosophy of yours? If your sticking to a conclusion that forces most of the data to become anomalous, then it’s probably a poor conclusion. As I’ve been saying all along, the data is inconclusive. You’re the one trying to fit a shape to it, but if it were really your intent to “follow the data” then you would at the very least accept its inconclusiveness. Your intent, however, is to push an ideology, I think, not science.
Originally posted by rue:
My position has been and continues to be: follow the data. In that we definitely agree.
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Finn,
http://en.wikipedia.org/wiki/Global_warming
Click on the graph to get a larger image
How to explain this to a non-scientist who apparently can't read a graph ...
Most warming occurred since 1980.
How you can find that:
In simple terms, find the total span of temperature change (it is 0.8, from a low of - 0.3 to a high of + 0.5). Then find the midpoint of temperature change (it is at + 0.1). Draw a horizontal line at + 0.1 to the point where the + 0.1 line crosses the temperature graph, and look down to find the year. It is 1980.
In 1980 the two lines clearly cross. It took 100 years (between 1880 and 1980) for the temperature to go halfway up to its current level. It took only 25 years (from 1980 to 2005) to go up the rest of the way.
While you are in Wikipedia, you might want to look up some basic information about global warming. You might also look up:
http://www.wordiq.com/definition/Global_warming_hypothesis which has an even-handed approach to the pros and cons of the global warming debate.
But, to get off the topic of this one chart, there is a better analysis of global warming than eyeballing a crude graph.
As global warming naysayers are always quick to point out, earth's temperature is about more than CO2. And that is where the utility of climate modeling happens. Its strength is its ability to account for other influences and feedback loops. The following graph shows modeled natural, anthropogenic and total global warming, and compares them against actual measures. The model, which runs from about 1860 to 2000, is accurate in calculating temperatures:
http://www.grida.no/climate/ipcc_tar/wg1/fig12-7.htm
This goes far beyond the lame 'eyeball' test, and it supports the idea of human-caused global warming.
Quote:SOME balloon and satelite data show minimal warming. Other data shows quite a bit. Recently: http://www.sciencedaily.com/releases/2004/11/041129113717.htm
Balloon and satellite data don’t show any appreciable warming at all.
Quote:Now, I did just post the url a little while ago so you should have no excuse for not having followed it up, but it seems you screen your data for conformance to your views.
In the case of the troposphere, the layer from the surface to an altitude of about 7.5 miles, where most weather occurs, it was believed there had been less warming than what was recorded at the surface. However, Fu's team determined the satellite readings of the troposphere were imprecise because about one-fifth of the signal actually came from a higher atmosphere layer called the stratosphere, which for the last few decades has been cooling several times faster than the troposphere has been warming.
And for anyone else who has made it this far:
Somewhat technical dissection of global warming debate, funny because it's unusually blunt:
http://cgi.cse.unsw.edu.au/~lambert/cgi-bin/blog/science/?_start=41
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Quote:Aside from her typical jab at me, what rue is referring to here is something that climatologists have dubbed “Mann’s Hockey Stick.” Although rue's grasp of the field seems to be rather sectarian, so let me explain. In 1999 Paleoclimatologist Michael Mann claimed to have reconstructed temperatures from proxy data, in this case tree rings, over the last 1000 years (Mann et al.). The paper presented the data in a graph, which is actually the very graph that rue is talking about. It has gotten a lot of publicity from the global warming advocates. Is Mann’s “hockey stick” correct? Well, certainly rue will tell you that its gospel. It can’t possible be wrong because it support her dogma. No matter what she claims about ‘following the data’ she has consistently pushed an ideology not the data. That’s her position. Here’s mine:
Originally posted by rue:
http://en.wikipedia.org/wiki/Global_warming
Click on the graph to get a larger image
How to explain this to a non-scientist who apparently can't read a graph ...
Most warming occurred since 1980.
How you can find that:
In simple terms, find the total span of temperature change (it is 0.8, from a low of - 0.3 to a high of + 0.5). Then find the midpoint of temperature change (it is at + 0.1). Draw a horizontal line at + 0.1 to the point where the + 0.1 line crosses the temperature graph, and look down to find the year. It is 1980.
In 1980 the two lines clearly cross. It took 100 years (between 1880 and 1980) for the temperature to go halfway up to its current level. It took only 25 years (from 1980 to 2005) to go up the rest of the way.
The truth is I don’t know. Maybe Mann is right. But if he is, how do you explain the balloon and satellite data, which show very little warming? How do you explain the “anomalies” in the data? But more importantly, why doesn’t Mann’s data represent the “Medieval warming period” and the “little ice age?” These are two events that have been documented with dozens, perhaps hundreds, of papers in historical study over dozens of years. In fact they are both quit accepted among historians and are both based on study and evidence that is completely independent of the global warming controversy. One would expect that these two events would be illustrated in Mann’s data, yet instead what Mann’s data seems to illustrate is the party line of the IPCC. Now maybe these two events never actually occurred, and thousands of historians have simply been wrong for apparently mysterious reasons, OR maybe Mann’s data is wrong.
An examination of Mann’s data actually raises several questions. First, Mann’s data is described as being for the Northern Hemisphere, but Mann actually included data from the Southern Hemisphere. Further the comparison between proxy data and measured temperature is questionable and is presented without error bars, and is admittedly base solely on a single sample for normalization of the data. Perhaps the certainty (or lack thereof) in the data was of less importance then the conclusion? I don’t know, but how much reliability is there in the proxy data? Tree ring data is dependent on more then just surface temperature: rainfall, fires, competition with other trees, infestations, to name a few. All of which add uncertainty, which was completely lacking in Mann’s paper.
Finally, McIntyre et al claims to have fixed some of the statistical uncertainties that plague Mann’s data, and arrived at a new reconstruction. Then more recently Esper et al supported McIntyre et al. Interestingly enough both of these reconstructions are not only more consistent with each other then with Mann’s reconstruction, but also with the Medieval Warming Period as well as the Little Ice Age. This means that at least it is more consistent with accepted data then Mann’s. It also doesn’t support either the IPCC’s or rue contention that the current apparent increase in global mean surface temperature is unique.
Mann, M.E., R.S. Bradley, and M.K. Hughes, 1999. Northern Hemisphere temperatur
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