Press Release 13-139
Seasonal carbon dioxide range expanding as more is added to Earth’s atmosphere
Northern Hemisphere land-based ecosystems “taking deeper breaths,” scientists find
![co2_weekly_mlo[1]](http://wattsupwiththat.files.wordpress.com/2013/08/co2_weekly_mlo1-e1376168771698.png?quality=75)
Levels of carbon dioxide in the atmosphere rise and fall each year as plants, through photosynthesis and respiration, take up the gas in spring and summer, and release it in fall and winter.
Now the range of that cycle is expanding as more carbon dioxide is emitted from burning fossil fuels and other human activities, according to a study led by scientists at the Scripps Institution of Oceanography (SIO).
The findings come from a multi-year airborne survey of atmospheric chemistry called HIAPER Pole-to-Pole Observations, or HIPPO.
Results of the study are reported in a paper published online this week by the journal Science.
The National Science Foundation (NSF), along with the U.S. Department of Energy, the National Center for Atmospheric Research (NCAR), the National Oceanic and Atmospheric Administration (NOAA) and the Office of Naval Research funded the study.
“This research provides dramatic evidence of the significant influence the land-based biosphere can have on the amplitude [amount of change] in seasonal trends of carbon dioxide exchange,” says Sylvia Edgerton, program director in NSF’s Division of Atmospheric and Geospace Sciences, which funded the research.
Observations of atmospheric carbon dioxide made by aircraft at altitudes between 3 and 6 kilometers (10,000-20,000 feet) show that seasonal carbon dioxide variations have substantially changed during the last 50 years.
The amplitude increased by roughly 50 percent across high latitude regions north of 45° N, compared with previous aircraft observations from the late 1950s and early 1960s.
This means that more carbon is accumulating in forests and other vegetation and soils in the Northern Hemisphere during the summer, and more carbon is being released in the fall and winter, says study lead scientist Heather Graven of SIO.
It’s not yet understood, she says, why the increase in seasonal amplitude of carbon dioxide concentration is so large, but it’s a clear signal of widespread changes in northern ecosystems.
“The atmospheric carbon dioxide observations are important because they show the combined effect of ecological changes over large regions,” says Graven.
“This reinforces ground-based studies that show that substantial changes are occurring as a result of rising carbon dioxide concentrations, warming temperatures and changing land management, including the expansion of forests in some regions and the poleward migration of ecosystems.”
Adds Peter Milne, a program director in NSF’s Division of Atmospheric and Geospace Sciences, “We can easily measure the greenhouse gas budget from a single smokestack, but somewhat less well for a stand of trees. Knowing that for the entire planet is much more challenging.
“Taking advantage of the long-duration and high-altitude-profiling capabilities of the NSF Gulfstream V aircraft [also known as HIAPER], the HIPPO project was designed to take a ‘snapshot’ of the global troposphere [Earth’s lowest atmospheric layer] to see whether we can explain and model greenhouse gas distribution.”
In the study, the scientists compared the recent aircraft data with aircraft data gathered from 1958 to 1961 using U.S. Air Force weather reconnaissance flights.
The older data were analyzed by SIO geochemist Charles David Keeling, the father of Ralph Keeling, also an SIO scientist and a member of the research team.
These aircraft measurements were done at the time Charles Keeling was beginning continuous carbon dioxide measurements at Mauna Loa, Hawaii.
While the Mauna Loa measurements are now widely recognized as the “Keeling Curve,” the early aircraft data were all-but-forgotten.
Carbon dioxide concentrations in the atmosphere have varied between 170 and 280 parts per million during the last 800,000 years.
When Charles Keeling began collecting data at Mauna Loa in 1958, the concentration had risen to about 315 parts per million.
In May, 2013, daily carbon dioxide measurements at Mauna Loa exceeded 400 parts per million–for the first time in human history.
Recent observations aboard the Gulfstream V were made during regular flights conducted during the HIPPO campaign, from 2009 to 2011.
The aircraft repeatedly ascended and descended from a few hundred meters to roughly 12 kilometers (40,000 feet) in the skies between the North Pole and Antarctica. The goal was constructing a unique snapshot of the chemical composition of the atmosphere.
Additional recent data comes from regular flights conducted by NOAA at a network of locations.
Increasing carbon dioxide amplitude since 1960 had already been observed at two ground-based stations: Mauna Loa and Barrow, Alaska.
Other stations operated by Scripps and NOAA only began measuring carbon dioxide in the 1970s to 1990s.
The aircraft-based observations uniquely show the large area in northern high latitudes where carbon dioxide amplitude increased strongly since 1960.
The exact reasons for the wider seasonal swings in carbon dioxide concentration remain to be determined, say the researchers.
Although plant activity can increase with warmer temperatures and higher carbon dioxideconcentrations, the change in carbon dioxide amplitude over the last 50 years is larger than expected from these effects.
Carbon dioxide concentration has increased by 23 percent, and average temperature north of 30°N has increased by one degree C, since 1960.
Other factors may be changes in the amount of carbon in leaves, wood or roots; changes in the extent or species composition of ecosystems; or changes in the timing of plant photosynthesis and respiration.
Simulating complex processes in land-based ecosystems with models is a challenge, scientists have found.
The observed change in carbon dioxide amplitude is larger than that simulated by models used by the Intergovernmental Panel on Climate Change (IPCC).
While this underestimate does not call into question the response of climate to carbon dioxide concentration in the IPCC models, the researchers say, it does suggest that a better understanding of what happened during the last 50 years could improve projections of future ecosystem changes.
The bottom line, according to Graven, Ralph Keeling and colleagues, is that Northern ecosystems appear to be behaving differently than they did 50 years ago.
In addition to Graven and Ralph Keeling, Science paper co-authors include Stephen Piper, Lisa Welp and Jonathan Bent of SIO; Prabir Patra of the Research Institute for Global Change in Yokohama, Japan; Britton Stephens of NCAR; Steven Wofsy, Bruce Daube and Gregory Santoni of Harvard University; Colm Sweeney of NOAA and the Cooperative Institute for Research in Environmental Sciences at the University of Colorado, Boulder; Pieter Tans of NOAA; John Kelley of the University of Alaska, Fairbanks and Eric Kort of the Jet Propulsion Laboratory in Pasadena, Calif.
-NSF-
Related Websites
NSF News: First Global Picture of Greenhouse Gases Emerges from Pole-to-Pole Research Flights: http://nsf.gov/news/news_summ.jsp?cntn_id=121566
HIAPER Pole-to-Pole Observations (HIPPO) Study: http://hippo.ucar.edu/
NSF Award: Collaborative Research: HIAPER Pole-to-Pole Observations (HIPPO) of Carbon Cycle and Greenhouse Gases: http://www.nsf.gov/awardsearch/showAward?AWD_ID=0628575
“Northern ecosystems appear to be behaving differently than they did 50 years ago.”
150 years ago humans used 4% of the land’s surface for agriculture and cities combined. Today we used 4% for cities alone and 40% for agriculture. Most of this change has taken place in the Northern hemisphere, because this is where the land is and this is where the wealth is.
The farmland from 150 years ago is now cities. Large portions of the grasslands, forests and even deserts from 150 years ago are now devoted to agriculture. And CO2 levels are now above the minimum required for C3 photosynthesis – something that was not true 150 years ago.
Of course there has been a change. The last 50 years have simply been a continuation of events that started 150 years ago as the world began to industrialize.
“The amplitude increased by roughly 50 percent across high latitude regions north of 45° N, compared with previous aircraft observations from the late 1950s and early 1960s”.
How much confidence do they have that the earlier observations (methods) are comparable to recent methods? If they are making some assumptions their conclusions may be bunk.
…. “more carbon is accumulating..during the summer, and more carbon is being released in the fall and winter, ”
Why is it that these scientists always seem to presume that there should NOT be this sort of variation over every time scale?
Isn’t it a wiser assumption that these many changes must occur as earth’s countless influences and responses are constantly varying individually?
How can nature possibly be stable? There is just too much going on.
“It’s not yet understood, she says, why the increase in seasonal amplitude of carbon dioxide concentration is so large, but it’s a clear signal of widespread changes in northern ecosystems”
“Northern ecosystems appear to be behaving differently than they did 50 years ago.”
IMO this kind of monitoring, comparing and speculation is useless and costly make work for the many professional ponderers. They’ve created careers out of what should be hobbies.
It’s all like monitoring sand dunes and trying to figure out why the shapes change.
I bet some years they change more than others. Isn’t that interesting?
Here in Oregon some of us are waiting and waiting (but not really) for the updated explanation for why there is nothing happening in the way of AGW Ocean Dead Zones. There never was.
Yet many millions are being devoured collecting water samples at various depths to monitor fluctuating oxygen levels because Jane Lubchenco, Jack Barth and Francis Chan cooked up an AGW connection to naturally occurring seasonal hypoxia and spread word of their fabrication around the globe. Their baseless pondering is everywhere. Google Oregon Ocean Dead Zones
and see the parasite of misinformation they infected the web with.
On previous post regarding the change in CO2 as measured at Mauna Loa, I have postulated that there appears to be both an annual cyclic CO2 change and a longer term change that warmists postulate can only be accounted for by the change in the evil burning of fossil fuels. I postulated an alternative theory, and have been busy trying to gather data to verify it. This ariticle seems to offer some proof or at least partially agree that my theory has merit.
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My theory postulates that to accurately determine the CAUSE of the change in gaseous CO2 in the atmosphere, one must accurately measure both the “sources” and the “sinks” that govern the instantaneous CO2 concentration. It further postulates that the long term drift upwards in the CO2 concentration must be directly correlated to BOTH the ADDITIONS to CO2 from all sources AND the LOSSES caused by the loss of SINKS such as tropical forest vegetation. I believe but still need to prove that long term net loss of tropical forest vegetation and the long term net addition from all volcanic sources, are far more likely CAUSES for long term upward drift in CO2 than the small addition man has contributed by burning fossil fuels.
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In this article the authors ponder the annual swing. They wonder why that swing has seen greater range in more recent years, and they ADMIT THAT THE ANNUAL CYCLIC SIGNAL IS CAUSED BY EXTRA PHOTOSYNTHETIC VEGETATION OUTSIDE OF THE TROPICS. Yet they fail to postulate that the long term upward drift is most likely associated with a change in vegetation that does NOT experience annual change, namely the long term loss of tropical forest vegetation! I wonder why not?
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What say you all here at WUWT? Do you think this theory has merit? Do you know of any solid proof or data that disproves it?
jorgekafkazar: The NSF article pretends absolutely nothing is happening below the equator.
No. They merely did not perform any measurements there.
Steve Oregon: Why is it that these scientists always seem to presume that there should NOT be this sort of variation over every time scale?
Isn’t it a wiser assumption that these many changes must occur as earth’s countless influences and responses are constantly varying individually?
How can nature possibly be stable?
There is not presumption in the article at all about what happened in eras for which they have no measurements. All they have done, and it wasn’t easy, is document (at least partially) a particular change over a particular era and over a particular space a change in one measurable feature of the environment. Now that it has been done, it can be done more regularly and systematically over the next decades to see what happens. Differences, if any, between the Northern and Southern hemispheres should be informative.
ferd berple: Of course there has been a change.
And, …, now it has been measured.
Richard G: This ain’t rocket science, or climate science, this is biology. The biosphere is opportunistic. More CO2 equals more life, from primary producers on through the web to decomposers. This is surprising?
It’s still better to have actual measurements than not to have the measurements.
I think that for people who do not already know everything important this is an informative article. Are there any old reference data sets for the Southern Hemisphere so an experiment like this can be conducted there and possibly quantity the changes that have occurred there over the same time span?
The larger swings in seasonal CO2 uptake/release in the NH seems to be related to a longer growing season and especially a decrease in freezing days in the upper North. See:
http://cce.nasa.gov/meeting_2011/abs_and_discussions/mtg2011_ab_searchab_id17.html
and its link to the interesting poster.
http://cceo.gsfc.nasa.gov/mtg2011_ab_presentations/2011_Poster_Kim_220_17.pdf
based on satellite temperature and local CO2 flux measurements.
Matthew R Marler wrote,
“Now that it has been done, it can be done more regularly and systematically over the next decades to see what happens. Differences, if any, between the Northern and Southern hemispheres should be informative.”
You sure do apply a lot of unfounded confidence in what they have supposedly documented.
I don’t buy it at all. Either on what they think they have compared or the idea that their hypothesized fluctuation is meaningful.
Whatever methods and measurements they have and used from the 50s and 60s are not as reliable as today’s. So these folks most likely did make some presumptions.
Measuring for the sake of measuring has become an endless and limitless pursuit with imaginations and speculation always delivering the notion that all of it is meaningful.
With the world having so many known things (already measured) needing attention and resources it is a crying shame that so much is being allocated to this professional hobby work.
If I were in charge much of it would end today. But I am but a simple man.
It’s a good thing when plant asphyxiation lets up?
Steve Oregon: You sure do apply a lot of unfounded confidence in what they have supposedly documented.
Really? I look forward to studies in the future based on the same methodology. Confidence in some empirical results might then be justified. I used the word “informative”. A few people on this thread already know why the supposed result has happened. You confidently assert that knowledge about atmospheric CO2 is irrelevant. I agree that’s simple.
Dave Wendt says:
August 13, 2013 at 3:52 am
Vegetal decay may not stop entirely in northern latitudes in fall and winter, but my experience of over six decades of life in southern Minnesota suggests it doesn’t really do much until the next growing season commences and that most plant material breakdown occurs in conjunction with new growth, not in opposition to it.
That is largely true, but the most soluble compounds (sugars, proteins) are already gone in the first weeks. What rests is the cellulose frame and lignin which remain rather intact at low temperatures and the latter even need strong chemicals by specific fungi to break down, which mostly happens at higher temperatures.
From some more search it seems that most winter CO2 release is from soil bacteria under the snow layer, here from near the treeline in Alaska:
http://academic.research.microsoft.com/Publication/41858630/snow-distribution-soil-temperature-and-late-winter-co-2-efflux-from-soils-near-the-arctic-treeline:
Results showed that greater wintertime C loss from forests could offset greater summertime C gain.
DonV August 13, 2013 at 8:46 am “Yet they fail to postulate that the long term upward drift is most likely associated with a change in vegetation that does NOT experience annual change, namely the long term loss of tropical forest vegetation! I wonder why not?”
They already add land use changes: http://cdiac.ornl.gov/trends/landuse/houghton/houghton.html That would seem to cover long term tropical forest loss.
“””””……eric1skeptic says:
August 13, 2013 at 3:27 am
jorgekafkazar (August 12, 2013 at 5:52 pm) “The NSF article pretends absolutely nothing is happening below the equator. Hint: record ice extent in Antarctica.”
I might need more hints. I don’t think the observed trough in atmospheric CO2 in July has anything to do with ice at either pole. Perhaps you are implying the cold temperatures in the SH in July before peak ice in the Antarctic would absorb more CO2? On the other thread George E Smith had the same theory except at the north pole instead of the south.
If ocean temperature were a better explanation of the annual wiggle than the biosphere, I would certainly be interested in that theory. But AFAICS, it is not………..”””””””””””
Well at the south pole, there is neither a biological cycle, nor an open water refreeze cycle. Consequently, there is very little atmospheric CO2 cycle at the south pole. The NOAA data I have seen, says the south pole cyclic amplitude, is about -1 ppm. On the other hand, at the north pole, and throughout the entire high Arctic, the CO2 annual cycle is 18-20 ppm amplitude; and in that region you have both an open water refreeze cycle, of some 8-12 million squ km of ice, and an associated ocean biological cycle (the whales go there to feed on it).
The small out of phase signal at the south pole is a vestige of the “well mixed” atmospheric CO2 cycle occurring at the sea ice edge of Antarctica, which is about – 0.5 times the ML cycle amplitude..
Meanwhile, in the tropics, which is where ML is situated; you tend to not see a biological cycle such as might be seen in New England. Vegetation in the oceanic tropics, tends to grow continually; there isn’t much seasonality.
But compared to that, you assert: “””””….. I don’t think the observed trough in atmospheric CO2 in July has anything to do with ice at either pole…….”””””” and this: “””””…..But AFAICS, it is not…..”””””
I think, you might be on to something with your theories.
From the story:
The observed change in carbon dioxide amplitude is larger than that simulated by models used by the Intergovernmental Panel on Climate Change (IPCC).
Well, paint me surprised…. Model fail, again.
Chip Knappenberger says:
August 12, 2013 at 1:50 pm
This is hardly a new concept.
The Idso’s have been all over this for more than 20 years.
http://www.co2science.org/subject/other/co2amp.php
-Chip
Exactly, this is no new find, but a comfirmation of the fertilization effect. As explained there:
“As can be seen from these data, over the period 1958-1999 the “breath” of the biosphere has been considerably enhanced. The 19.5% increase in the strength of this phenomenon is primarily a direct result of atmospheric CO2 fertilization (Pearman and Hyson, 1981; Cleveland et al., 1983; Bacastow et al., 1985; Enting, 1987; Kohlmaier et al., 1989; Keeling et al., 1996), nitrogen-induced increases in the growth rates of earth’s ecosystems (Shindler and Bayley, 1993; Hudson et al., 1994; Galloway et al., 1995), and CO2-induced expansions in some of their ranges (Idso, 1995). A slight temperature increase reported in some Northern Hemisphere land areas over this time period may also be a contributing factor (Keeling et al., 1996; Myneni et al., 1997). Together, these phenomena combine to produce the results shown in the graph above, which stands as a strong testament to the reality of the ubiquitous “greening of the earth” (Idso, 1986) that is currently in progress.”
Thanks for posting the link from CO2 science, they have a very good database about plants fertilization effect through CO2:
http://www.co2science.org/data/plant_growth/plantgrowth.php
Jimbo says:
August 12, 2013 at 4:10 pm
Exactly, the greening has been obeserved by satellites too, so wonder who is wondering?
http://wattsupwiththat.com/2008/06/08/surprise-earths-biosphere-is-booming-co2-the-cause/
DonV says:
August 13, 2013 at 8:46 am
What say you all here at WUWT? Do you think this theory has merit? Do you know of any solid proof or data that disproves it?
Don, in the link I posted above you can read:
From the 2004 abstract: Our results indicate that global changes in climate have eased several critical climatic constraints to plant growth, such that net primary production increased 6% (3.4 petagrams of carbon over 18 years) globally. The largest increase was in tropical ecosystems. Amazon rain forests accounted for 42% of the global increase in net primary production, owing mainly to decreased cloud cover and the resulting increase in solar radiation.
So it looks like tropical rain forrest where not cut do indeed increase.I think this disproves your thesis, however I do not have data showing tropical forrest globally.
re ferd berple says:
August 13, 2013 at 6:35 am
Off topic but still somewhat relevant to posts referring to agriculture. By comparing global population to arable land utilised, it takes on average 2 hectares to feed one human.
However in India the average is just 1 ha per human whilst in China it’s 2 ha per human and in USA it’s a whopping 9.4 ha per human.
george e. smith says:
August 14, 2013 at 10:59 am
Well at the south pole, there is neither a biological cycle, nor an open water refreeze cycle.
The latter seems not right: the seasonal freezing/melting of sea ice around the South Pole seems to be larger than around the North Pole:
http://www.climate4you.com/images/NSIDC%20GlobalArcticAntarctic%20SeaIceArea.gif
Thus if the sea ice area was the cause of the larger swings, they should be larger in the SH, as less suppressed by (land) vegetation.