Study: CO2 impacts could last centuries
Rising levels could lock in droughts, sea level increases
By Todd Hartman, Rocky Mountain News
Published January 27, 2009 at 12:05 a.m.
Photo by Matt Mcclain / The Rocky
According to a new study, rising levels of the greenhouse gas carbon dioxide this century could create drought conditions in many areas of the world that could last centuries into the future. The change also could lock in sea level increases over the next millennium.
Rising levels of the greenhouse gas carbon dioxide could create "irreversible" drought and sea level increases lasting for centuries, even if humans eventually succeed in significantly reducing emissions.
A new study, led by Boulder- based scientist Susan Solomon, warns of the danger of presuming that society can forestall a future climate emergency by quickly and dramatically cutting emissions.
"Our study convinced us that current choices regarding carbon dioxide emissions will have legacies that will irreversibly change the planet," said Solomon, who is based at the National Oceanic and Atmospheric Administration's Earth System Research Laboratory in Boulder.
The paper, published Monday in the Proceedings of the National Academy of Sciences, focuses on two impacts of climate change - drought and sea level rise - that scientists believe they can tie with increasing confidence to rising greenhouse gases.
Scientists said peak levels of carbon dioxide predicted in the coming decades could return the American Southwest to drought levels of the 1930s Dust Bowl era as well as drive up sea levels high enough to create "unavoidable inundation of many small islands and low-lying coastal areas."
The study examines the consequences of allowing the buildup of carbon dioxide - spewed into the atmosphere by cars, power plants and other fuel-burning sources - above present-day concentrations of 385 parts per million to 450 to 600 ppm that could be reached during the 21st century.
At those levels, rainfall decreases in already dry regions could expand, bringing drought to southern Europe, northern and southern Africa, western Australia and the southwestern United States.
The drops in rainfall would be expected to last for centuries, crimping water supplies, increasing wildfire threats, expanding deserts and harming agriculture.
Rising CO2 levels this century would also lock in sea level increases over the next millennium, the paper said.
Warming causes the ocean to expand, and that alone - independent of potential impacts from melting glaciers and ice sheets - could account for a sea level rise of 1.3 to 3.2 feet were carbon dioxide to peak at 600 ppm. The rise could double should CO2 peak at 1,000 ppm, the paper said.
"We presented the minimum sea level rise that we can expect from well-understood physics, and we were surprised it was so large," Solomon said in a statement provided by NOAA.
The authors noted that global warming impacts could include numerous other effects, including the retreat of Arctic sea ice, increases in heavy rainfall and flooding in some regions, permafrost melt, loss of snowpack and increased intensity of storms.
hartmant@RockyMountainNews.com or 303-954-5048
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January 27, 2009
9:15 a.m.
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CUBill writes:
What a ridiculous study! They are trying to model something that might not happen, hundreds of years out, with nothing more than assumptions and a poorly programmed computer. They can't even predict the weather next month! I think we've found a great place to start cutting wasteful government spending. The alarmists at NOAA have to go!
January 27, 2009
9:54 a.m.
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Fisherman writes:
The earth has been cooling for the last 10 years without a decrease in CO2. How can this be if CO2 is supposed to cause man-made global warming?
http://www.mlive.com/opinion/flint/in...
January 27, 2009
10:02 a.m.
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elkman writes:
According to the article:
"Scientists said peak levels of carbon dioxide predicted in the coming decades could return the American Southwest to drought levels of the 1930s Dust Bowl era as well as drive up sea levels high enough to create "unavoidable inundation of many small islands and low-lying coastal areas"
So, by that reasoning, the Dust Bowl era was caused by an increase in CO2?
The problem with the "studies on CO2" is that most of them take a very small segment of time to study and base their facts on. Look at the entire geologic history of the earth and one will find that there have been many rises and peaks in CO2 levels. However, man was not there to cause it. As soon as the CO2 levels peaked, they declined. All by themselves. How is that explained? I believe that dust levels in the air may have had much more of an impact on "global warming" than CO2 levels.
January 27, 2009
10:13 a.m.
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greenleaf writes:
Actually fisherman,
That isn't even close to being accurate. Your source is from a biased journalist I'm afraid. The following is a scientific journal report stating that 11 of the warmest years occurred in the last 13 year period.
http://www.sciencedaily.com/releases/...
1998 was an El Nino year which was unusually warm making succeeding years appear relatively cooler. It was truly an anomaly.
http://www.pmel.noaa.gov/tao/elnino/e...
January 27, 2009
11:10 a.m.
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greenleaf writes:
elkman,
Indeed there exist natural sources for CO2. Everything from volcanoes to animals and decaying vegetation produce it. It fluctuates with these natural phenomena.
You ask: " However, man was not there to cause it. As soon as the CO2 levels peaked, they declined. All by themselves. How is that explained?"
Using the example of volcanoes, they erupt and then stop. A single event can produce vast quantities of CO2 and then stop doing so when the event subsides. That is the supply side. On the consumer side, there exist various CO2 sinks that absorb CO2 from the atmosphere. These include the ocean, undisturbed soil and forests. Given an opportunity,the earth gradually returns to some degree of CO2 equilibrium unless new volcanoes erupt or another factor such as man directly pumps more CO2 into the atmosphere or contributes indirectly by cutting down forests and tilling large acreages of soil, both of which eliminate CO2 sinks.
January 27, 2009
11:20 a.m.
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Fisherman writes:
Actually, greenleaf, during the last 10 years the earth has been on a cooling trend. Regardless of whether El Nino affected it or not, the carbon dioxide levels did not decrease, instead they increased during that 10 year time period. How do you explain that if carbon dioxide is responible for warming?
http://blog.t1production.com/cooling-...
http://en.wikipedia.org/wiki/Carbon_d...
January 27, 2009
11:51 a.m.
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greenleaf writes:
Fisherman my friend, You have to stop getting your scientific information from biased, non scientific sources.
CO2 concentrations are, indeed, increasing and, in fact, accelerating. Here is a 1997 report on increasing CO2 and methane from NOAA a federal scientific research agency which I believe trumps your blog as a better source of information. Its always better to get it from the source.
http://www.noaanews.noaa.gov/stories2...
So, you are right about CO2 increasing but average temperatures are as well. I will repost my link from my previous post that supports that statement.
http://www.sciencedaily.com/releases/...
Since that wasn't enough, here is NASA Goddard's report on the temperature increase we are continuing to witness:
http://data.giss.nasa.gov/gistemp/2007/
For credibility and accuracies sake fisherman, I would recommend going directly to research data sources and to scientific journals where data sets and analysis can both be found in an unbiased setting. This cranky old scientist can't accept the cherry picking sites on both sides of the AGW debate as validating anything and you shouldn't either.
January 27, 2009
11:57 a.m.
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luckyleif writes:
Nice of greenleaf to point out that the vast majority of atmospheric CO2 is natural (96%). Even so, it's a weak greenhouse gas, much less important than water vapor and clouds.
Propagandists like Solomon want us to believe reducing human CO2 will have some miraculous effect. Their agenda is control of the economy, not of the climate. The thousand-year residence time is their latest fantasy.
Too bad Hartmann and the Rocky continue to push this nonsense.
January 27, 2009
1:11 p.m.
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elkman writes:
greenleaf
I believe you need to do a little more research on volcanoes. Volcanoes produce more ash, dust, and sulfur dioxide, than CO2. So, I don't think your logic holds up. With increased volcanism, the earth actually cools down. Why? Because the dust, and ash act as reflectors of sunlight. Much of the sunlight is reflected back into space. Therefore, the earth cools. Nice try, but no cigar on that one.
January 27, 2009
1:16 p.m.
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greenleaf writes:
elkman,
we weren't talking about ash, we were talking about CO2. and it is only one of the CO2 sources.
January 27, 2009
1:22 p.m.
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Fisherman writes:
I agree that carbon dioxide and AVERAGE global temperatures are rising, greenleaf, but if you look at the chart from the website that spoke about cooling trends, the chart they cite shows:
"All four major global temperature tracking outlets (Hadley, NASA’s GISS, UAH, RSS) have released updated data. All show that over the past year, global temperatures have dropped precipitously." Where is the drop in carbon dioxide?
The period from 1998 to 2008 shows a decline, or at least a stable trend to earth's average temperature, over that period. A 10 year cooling trend must have an effect on carbon dioxide concentrations in the atmosphere if you ascribe to AGW. Just as you can correlate short periods of 10 years showing temperature and carbon dioxide climbing, you should see a decrease or stabilization of carbon dioxide in a 10 year period where temperature are falling or stabilizing, or your AGW theory makes no sense at all. How can you have it both ways?
January 27, 2009
1:29 p.m.
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elkman writes:
greenleaf
Ash and dust are one and the same. They are both small particles that reflect sunlight. So, yes, we are talking about ash, because you brought up volcanoes. And no, volcanoes are not a viable source for CO2. You still have not explained the sudden rise and decline of CO2 throughout geologic history. Again, volcanism would mean a decrease in global temperature, not an increase.
January 27, 2009
1:37 p.m.
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elkman writes:
greenleaf
You present web sites based on less than 120 years of data and expect people to believe it? Look at geologic history and then compare CO2 levels. Then you will be a little more educated on the rise and decline of CO2 throughout history, not just a snapshot of a very insignificant amount of time.
January 27, 2009
4:21 p.m.
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greenleaf writes:
elkman,
Ok buddy, let's add about a130 years to that and go with ice core data. This starts at a preindustrial data point.
atmospheric air still circulates through the open pores (Friedli et al. 1986). The enclosed air was younger than the surrounding ice because the enclosure of air in bubbles occurred only between depths of 64 and 76 m. On the basis of porosity measurements, investigators determined that the time lag between the mean age of the gas and the age of the ice was 95 years and that the duration of the close-off process was 22 years (Schwander and Stauffer 1984). Neftel et al. (1985) concluded that the atmospheric CO2 concentration ca. 1750 was 280±5 parts per million by volume (ppmv) and that it increased by 22.5% to 345 ppmv in 1984 essentially because of human factors. Graphs in Friedli et al. (1986) also reported that the preindustrial (pre-1800) CO2 concentration was ~280 ppmv.
http://cdiac.ornl.gov/trends/co2/sipl...
Now, we are approaching 386 ppmv.
http://www.esrl.noaa.gov/gmd/ccgg/tre...
As for the gas mixture coming from volcanoes, its apparently the number 2 gas after water vapor. Your point about ash isn't lost upon me. As a botanist, I couldn't ignore the effects of Mt. Pinatubo's Ash cloud the year it erupted. It was a miserable year in which to grow anything. Here in Denver it was too cold and wet. The problem with what you are saying elkman is that ash settles out of the atmosphere far faster than CO2 settles into the sinks I mentioned above.Here is a breakout of gas releases from several volcanoes under study.
http://volcanoes.usgs.gov/hazards/gas...
January 27, 2009
5:17 p.m.
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greenleaf writes:
elkman,
Here is another data set of CO2 starting in the year 1000 A.D.. Note how constant CO2 levels are until the beginnings of the industrial revolution around 1850.
http://www.johnstonsarchive.net/envir...
January 28, 2009
7:17 a.m.
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elkman writes:
greenleaf
Again, you are taking a snapshot in time. 1,0000 years, is a drop in the bucket. LOOK at the entire geologic record. Then you will see that your data is so compelling. The earth is about 4.5 billion years old. Not 120 or 1,000! Base your data on the entire geologic record!
January 28, 2009
9:38 a.m.
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greenleaf writes:
elkman,
Thought I would check back one last time and there you are!
I don't think that anything this old Botanist would say to you would make much difference elkman. We actually have ice core data going back 50,000 years. Based upon your comments, that wouldn't be good enough. Were I to spend umpteen hours digging up (pun intended) whatever ancient data I could find, you would still say it isn't old enough! In fact, we don't have data going back 4.5 billion years. Even if we did, its credibility would be dubious at best. If you are totally unwilling to accept the statistically unlikely one to one correspondence between the increase in human produced CO2 since the beginning of the industrial revolution and the increase in the earth's temperatures which had been stable for hundreds of years prior to that, there isn't much hope of influencing your opinion today, if ever. While any scientist would say there is a slight possibility that man isn't causing this, that its just a remarkable coincidence, statistics aren't on the side of that argument I'm afraid. I'll leave you with one thought: isn't it better to believe, based upon pretty overwhelming evidence that man is having at least some impact on Global Warming, than to toss hands in the air, say you are helpless to assist future generations and just continue your wasteful consumption of the products that probably got us into this situation in the first place?
I prefer to err, if it is erring, on the side of energy conservation, which is a fiscally responsible concept in addition to helping us with both our energy challenges and AGW. Funding alternative energy concepts can create jobs here and dry up the outflow of our treasury to the Middle East and help to mitigate AGW as well. Just something to think about on this dying thread.
January 28, 2009
10:12 a.m.
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elkman writes:
I prefer to look at the total geologic record and look at the rise and fall of CO2. Those rises and falls had nothing to do with man. Selective data analysis is often the downfall of all theories.
January 28, 2009
11:07 a.m.
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greenleaf writes:
elkman,
So.....how far back can you go? I contend that what you propose is impossible. We have geological strata and radiocarbon dating, some fossils, none of which speak to the relationship between CO2 and temperature. As a scientist, I agree totally that data mining is unscientific. However, in this case, if CO2 is having a negative impact that we could mitigate and all we have to work with is a 100,000 year old data set, we have to work with that. We have no alternative. Using your logic, can you prove that man is having no effect on Global Warming? We certainly have a well defined effect on every other part of the environment including the air we breathe, the water we drink, the plants and animals that share the planet with us. We divert rivers, create vast reservoirs, pave millions of acres, log millions of acres of trees, drive animals and plants to extinction. There is no end to the effects we have had and continue to have on the natural world. Why is it so hard to accept that we are contributing to Global Warming to some degree?
Forgive me, but it seems too convenient to sit on one's hands and to say "prove to me based upon 4.5 billion years of CO2 and climate records that AGW exists" when you know very well that information doesn't exist and never will. Sometimes we have to work with what we have and 100,000 years of data on this specific subject seems pretty darn good to me.
January 28, 2009
1:34 p.m.
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elkman writes:
greenleaf
According to my research, the earth has warmed only 1.4 degrees F. in 150 years (1850-2000). If CO2 rises and temperature rises (as you maintain), then, if CO2 levels drop, temperature must also drop. According to the stats, this has only been true 25% of the time. I am sure you have heard of the Vostok data? It goes back 450,000 years. A little further than your 1,000 data. That data shows 5 distinct peaks in CO2. Again, man had nothing to do with those levels peaking. Twice in geologic time, CO2 levels have been near what they are today. Both times the temperature was 53 and 68 degrees F. Today the average temp is? 57 degress F. So, I have a hard time blaming man for things that happen naturally. Seems to me that Gore and his associates just want to scare the public and then make money on it. Like carbon credits. Give me a break.