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Space Science

NASA Satellite Measures Earth's Carbon Metabolism 141

Posted by michael from the fat-burning-machine dept.
Roland Piquepaille writes "To celebrate Earth Day, the NASA Earth Observatory recently revealed global measurements of the Earth's metabolism. 'Combining space-based measurements of a range of plant properties collected by the Moderate Resolution Imaging Spectroradiometer (MODIS) with a suite of other satellite and surface-based measurements, NASA scientists produce composite maps of our world's 'net primary production' every 8 days. This new measurement is called net production because it indicates how much carbon dioxide is taken in by vegetation during photosynthesis minus how much is given off during respiration.' Check this column for a summary including the usefulness of such measurements. You'll also find maps showing the seasonal variation of Earth's net primary production."
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NASA Satellite Measures Earth's Carbon Metabolism More

NASA Satellite Measures Earth's Carbon Metabolism

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  • The Earth's not fat... (Score:5, Funny)

    by gpinzone ( 531794 ) on Friday April 25, 2003 @07:56AM (#5807451) Homepage Journal
    It just has a low metabolism.

  • Now show where carbon get produced! (Score:5, Insightful)

    by Ja-Ja-Jamin ( 661760 ) on Friday April 25, 2003 @07:57AM (#5807454)
    Show where it gets produced contrasted with where it gets consumed and show the rate of the difference. Combine that with charts showing how typical day to day activities contribute to either column. Now you'll have something that can help the average person make a difference! This is a good start!

  • These kinds of studies... (Score:5, Interesting)

    by Ratphace ( 667701 ) on Friday April 25, 2003 @07:57AM (#5807458)

    ...are really important IMHO. Studying the carbon dioxide levels of any system is important because with the talks about someday inhabiting other planets like Mars, one of our first objectives would be getting greenhouse gases into the planet's atmosphere and then waiting many years for the planet to warm up enough to be inhabitable, both from a temperature standpoint and melting the ice caps at the poles (speaking of Mars of course).

    I am glad to see some useful studies being done. Once a planet warms up enough with green house gases, we can get some plant life on the planet to assist in the creation of oxygen through this same cycle and eventually make a planet liveable. Though it's not something we'll see in our lifetimes, studies such as these benefit the species as a whole in the long run (i.e. big picture of time).

    • Re:These kinds of studies... (Score:4, Insightful)

      by sigep_ohio ( 115364 ) <drinking@seven.am.is.bad> on Friday April 25, 2003 @08:23AM (#5807580) Homepage Journal
      I always thought that Mars lacked the gravity to hold a sufficient amount of greenhouse gases. I mean doesn't it have like 1/3 the gravity of earth, which means it wouldn't be able to hold the same amount of atmosphere. Additionally, it is farther from the sun, so it gets less light. That would mean it would need more greenhouse gases than earth does. Added together it means that Mars can't be terraformed like in the movies.

      Maybe I am missing something, but thats how I figure it. I am certainly no expert in the field, so anyone no better?

      • Re:These kinds of studies... (Score:5, Interesting)

        by Daniel Dvorkin ( 106857 ) on Friday April 25, 2003 @08:42AM (#5807697) Homepage Journal
        It seems to me that both the Earth and Mars are far below the limit of possible atmospheric density for their size. Consider Venus: slightly smaller than Earth, but it has a much, much denser atmosphere. If that kind of stuff scales linearly (and I don't have any idea of it does; I'm just guessing) then Mars would have no trouble holding on to an atmosphere as dense as Earth's.

        I think I remember reading somewhere that the Moon -- with its surface gravity of 1/6 g -- could hold on to an Earth-density atmosphere for something like 10,000 years. Wish I could remember more.
        • I agree with everything you say, but thought it worth pointing out that it's not as simple as you make it out to be.

          Venus is not just slightly smaller than the Earth. The Earth is around 20% more massive than Venus, being somewhat denser, so notwithstanding the relatively small difference in radius, the surface gravity on Venus is only about .91g. Mars is not nearly as dense as the earth and is quite a bit smaller, which accounts for its .38g surface gravity.

          What you say is true, though. Venus holds a

      • Re:These kinds of studies... (Score:1, Informative)

        by Anonymous Coward
        Keep in mind that 70% of Earth's greenhouse effect is from water vapor.

        Even if Mars is leaking gases, it takes a long time. Maybe we'd have to keep vaporizing water ice in the atmosphere to keep replenishing it. There is a lot of ice out there, most visibly in comets and the rings of Saturn.

      • I always thought that Mars lacked the gravity to hold a sufficient amount of greenhouse gases.

        This is part of the story, but certainly not all of it. A far more important factor is that Mars has no magnetosphere. The magnetosphere is what protects the Earth (and Venus) from the solar wind, which is a massive flow of charge particles and radiation from the Sun. Because Mars lacks this protection, any atmosphere imparted upon it would slowly be stripped away by the solar wind. This is likely one of the
        • Ah, I forgot about that magnetosphere thing.

          Maybe Mars just had a smaller core, which could not sustain its molten qualities for a very long period. It seems to me Mars' core may not have formed with as much heavy elements(like iron), instead they were more evenly distibuted throughout the planet. Maybe that's what caused Mars to lose its magnetosphere.

          or maybe A crimson caped guy in a shiney metal cap came along and stopped the core to kill off all the prejudice inhabitants.

      • Re:These kinds of studies... (Score:4, Informative)

        by Idarubicin ( 579475 ) on Friday April 25, 2003 @02:36PM (#5810846) Journal
        I always thought that Mars lacked the gravity to hold a sufficient amount of greenhouse gases.

        Well, that depends on how long you want to hold the gases. At any given temperature, the molecules of a gas at thermal equilibrium (or practically speaking, anywhere close to it) will have some distribution of speeds. Some molecules will travel faster, some slower. The mathematical expression characterizing this range of speeds is the Maxwell distribution. Here's [wolfram.com] a mathematical treatment of the Maxwell distribution; this page [davidson.edu] presents a nifty Java applet showing how this equilibrium takes place.

        Note that a plot of population vs. speed, the Maxwell distribution tails off at higher velocities, but never actually goes to zero. In an atmosphere, this means that a small number of molecules will periodically get kicked up to above escape velocity through collisions with other molecules in the gas. If they happen to be heading the right direction, then they will escape into space.

        Each molecule in a gas (on average) has roughly the same amount of kinetic energy. Earth's atmosphere contains very little hydrogen and helium because these light elements travel faster for a given amount of kinetic energy and escape more readily. A good part of the velocity distribution for these species is above escape velocity. Oxygen and nitrogen (not to mention water vapour and carbon dioxide) are significantly heavier, and bleed off at a much lower rate.

        Moving to Mars. The surface gravity is only about forty percent that on Earth, if I remember correctly. It's a much shallower gravity well, and escape velocity is much lower (5 km/s on Mars vs. 11 km/s for Earth). Since kinetic energy is a function of the square of velocity, it takes a significantly smaller push to move a molecule out of Mars' hold. Nevertheless, there actually is still only a very small tail of the Maxwell distribution that sits above Mars' escape velocity.

        I should also mention that there are sputtering processes that remove gas from the Martian atmosphere. Lacking a strong magnetic field to deflect the solar wind, a significant amount of gas is lost to sputtering, as well.

        Nevertheless, even the most pessimistic estimates suggest that an atmosphere similar to Earth's would last tens of thousands on years on Mars. A short lifespan in terms of planetary evolution--a long time for human beings. Even the Moon would take from one to ten thousand years (depending upon who you ask) to bleed off an Earth-like atmosphere. Recall that Mars has surface features strongly suggestive of flowing surface water. (Liquid water requires an appreciable atmosphere, otherwise it just boils off.) That sort of erosion takes a long time to happen, which further supports the notion that Mars can hold on to an atmosphere, at least for a few million years at a time.

    • Im confused... (Score:3, Funny)

      by t0ny ( 590331 )
      Once a planet warms up enough with green house gases, we can get some plant life on the planet to assist in the creation of oxygen through this same cycle and eventually make a planet liveable. Though it's not something we'll see in our lifetimes, studies such as these benefit the species as a whole in the long run (i.e. big picture of time).

      But... I dont understand... Rush Limbaugh tells us that there is no such thing as the greenhouse effect...

  • Coniferous forests (Score:5, Interesting)

    by Anonymous Coward on Friday April 25, 2003 @08:05AM (#5807491)
    I'm surprised that the coniferous forests in far north North America and Eurasia are more productive than the deciduous forests of more temperate climates. I'm wondering if the results of this are skewed because the temperate regions produce more carbon dioxide in the form of combustion emissions.
    • That means the fate of the world rests on Canada and our Popeye-looking head-of-state.

      We're doomed.

    • Re:Coniferous forests (Score:5, Insightful)

      by sigep_ohio ( 115364 ) <drinking@seven.am.is.bad> on Friday April 25, 2003 @08:13AM (#5807528) Homepage Journal
      Well in June the earth's northern hemisphere is facing the sun, so norhtern plants are more productive. In December the Southern hemisphere is facing the sun, and so plants in the south are more productive. Meanwhile between the tropics light levels do not differ significantly throughout the year, so there is not much fluctuation in plant productivity.

      atleast thats how I read the pictures.
    • These measurements don't include carbon dioxide emitted from fires--it's just the amount of carbon living plants take in minus the amount they respire.

    • Re:Coniferous forests (Score:5, Interesting)

      by SEWilco ( 27983 ) on Friday April 25, 2003 @09:23AM (#5807947) Journal
      Um.. That's relatively more productive. See how much more active the Amazon area is? Now, that blue ring southeast of it is not a desert, it is merely covered with trees and grass similar to what you'd imagine the Iowa farmland to be (yes, the color of Minas Gerais and Iowa are similar). The purple is less active, like the grasslands of Wyoming (indeed, the "northeast Brazil [terravista.pt]" area is known for its dry land and ranchers, as are the pampas further south).

      The forests along the east coast of the USA include those on the minor mountains of the Appalatian range -- a difficult area to farm. Also in there are the Smoky Mountains, named because often there is a haze due to the volatile chemicals (terpenes) released by the forest there.

    • The old rain forests are in equilibrium. Old trees die and rot (or burn) and only some carbon is fixed most is re-released and balanced out by the growth replacing the old trees.

      The coniferous forests of the northern hemisphere are often actively logged so have much young vigourous carbon fixing growth with the carbon being cut down and dragged off to make paper/ikea furniture.

      • Re:Coniferous forests (Score:3, Interesting)

        by SEWilco ( 27983 )
        Any area which is extracting more carbon than is emitted will build up soil. That's why the prairies of the US midwest had six feet of black dirt.

        There are many reports that the layer of topsoil in the Amazon is thin, which indicates it either is in a delicate balance or, more likely, negative balance. Probably a lot of the carbon is being washed away, and the forest is living on the recently produced soil. The Amazon is consuming more carbon than it emits in the air, but is leaking carbon downstream.

    • It looks to me that some of those areas of high activity are around the Great Lakes, including southern Ontario. The area is mostly deciduous. It really highlights the importance preserving the Carolinian Rainforest. Most of it between here (Toronto) and Detroit has been cleared and just reduced to scattered disconnected pockets. Very sad. I know somebody with a cottage in Rondeau Park on Lake Erie - it's all Carolinian rainforest around there and it's fantastic to get in it and see all the vegetation

    • Re:Coniferous forests - some numbers (Score:1, Informative)

      by Anonymous Coward
      ecosystem type area npp
      (10^12 m^2) (kg(C)/m^2/yr)
      .tropical forests 24.5 0.83
      temperate forests 12.0 0.56
      boreal forests 12.0 0.36

      woodland and shrubland 8.0 0.27
      savanna 15.0 0.32
      grassland 9.0 0.23
      tundra and alpine meadow 8.0 0.065
      desert scrub 18.0 0.032
      rock, ice, and sand 24.0 0.015
      cultivated land 14.0 0.29
      swamp and marsh 2.0 1.13
      lake and stream 2.5 0.23
      open ocean 332.0 0.057
      upwelling zones 0.4
    • Another strong factor that must play into this is the fact that the Northern America/Eurasia areas have the highest concentration and greatest diversity of coniferous trees anywhere on the globe. Coniferous trees metabolize CO2 all year round because they don't loose their leaves every fall. Because they metabolize all year round they are more productive than temperate deciduous regions.

  • Interesting (Score:5, Interesting)

    by Musashi Miyamoto ( 662091 ) on Friday April 25, 2003 @08:09AM (#5807509)
    If I understand the pictures correctly, it's amazing to see how much carbon is converted in the northern hemisphere... in Canada and Russia. It counters the conventional wisdom of the Amazon as being the primary oxygen producing region.

    It will make me doubt all those "save the rain forest" tree-huggers.

    I wonder if they could do the same thing to show the amount of carbon being produced.

    • Re:Interesting (Score:5, Insightful)

      by edgrale ( 216858 ) on Friday April 25, 2003 @08:25AM (#5807588)

      Please note that the amazon rain forest is producing oxygen all year long, even when the northern hemisphere has winter. And when the amazon is producing less it is "winter" over there.

      Unlike the northern hemisphere, the amazon produces oxygen even when it is "cooler" there. To quote the article, you did read it and not just look at the pictures?

      "However, tropical forests are more productive over a full year because of their longer growing season."
      • What you mean these articles are hear for me to read? I thought this was like the playboy magazine; the articles are filler, the real meat is in the pictures.
        • I sure am a product of the american education system. I couldn't even see that I wrote 'hear' instead of the correct form 'here'. Sorry about that.

    • Re:Interesting (Score:5, Insightful)

      by Catskul ( 323619 ) on Friday April 25, 2003 @08:31AM (#5807631) Homepage
      Well there is alot of importance to the rainforests besides their carbon consumption. I think one of the real resources is the bio-diversity.

      If (notice the emphasis) the carbon consumpton of the rainforests is, as it seems in these diagrams, not as significant as many have been lead to believe, then it has been irresponsible for those who are trying to protect this resource to over emphasize some particular data just because they believe they can get more attention that way. It seems to happen in every aspect of politics though. The use of half-truths is a powerfull political weapon that many cant resist using.

      • Re:Interesting (Score:3, Informative)

        by SEWilco ( 27983 )
        Look at the code key under the images again. Yellow and red are the most productive. The Amazon is consuming carbon dioxide at a faster rate than Florida.

        However, this only shows there are a lot of plants hard at work on the atmosphere there. It does not show what is happening to the carbon in dead trees, soil, mud flowing down the river, carbon entering from the mountains upstream...

    • Re:Interesting (Score:1)

      by Anonymous Coward
      It will make me doubt all those "save the rain forest" tree-huggers.

      Sorry to rant a bit, but the above statement is a cop-out.

      Did it ever dawn on you that maybe they want to save the rain forest for more important reasons than that it producing oxygen? Or maybe just because it's the right thing to do? Considering what they're up against, it's no wonder they try and use lesser points to convince the selfish-minded to use moderation.
    • Right, butif you run the movie, youll notice the northern hemisphere is only producing the same as the rainforest for half a year. So net for the whole year, the rainforest abssorbs about twice as much as the northern hemisphere forests do.
    • If you look at the net-primary productivity image on the NASA site, it's obvious that the Amazon region (as well as areas of the Phillipines) ARE in deed the most productive areas.

      Canada and Russia still end up absorbing CO2 on a yearly basis in this average, but the Amazon is about twice as productive per unit area.

    • Re:Interesting (Score:5, Informative)

      by robsimmon ( 462689 ) on Friday April 25, 2003 @09:04AM (#5807824)
      Actually the Amazon takes up 10% of the carbon absorbed by the Earth's land surface with only 5% of the land area--so it's a major source of oxygen. But the Amazon's a pretty complicated place--these maps only show part of what's going on there. Read (shameless plug, but then again the original story is from my site, too) Escape from the Amazon [nasa.gov] for a few details on the other half of the process.
      • Hey, great site. Shows nicely how some pieces of the Amazon carbon budget were matched. I like the right-angle radar reflector, too. I hope more pieces are gathered soon.
    • I typically take the word of the tree-hugger with a grain of salt as it is. Generally environmentalists are very impulse minded. They see something and immediately assume it is a trend.

      Is global warming actually occuring? Perhaps. But it is probably more due to a cycle that the planet is experiencing than mankind driving his car to work everyday. We were in an ice age at one time, after all.
    • It will make me doubt all those "save the rain forest" tree-huggers.

      Those "tree-huggers" are trying to save forests up north as well.

      And in both cases, the reason for saving forests is not that one or the other is the world champion at fixing carbon dioxide, it's that they are large, complex, and irreplaceable eco-systems.

      If I understand the pictures correctly, it's amazing to see how much carbon is converted in the northern hemisphere...

      No, you don't understand those pictures correctly. You shou

  • NASA measures Webchat's USER Metabolism (Score:1, Funny)

    by Anonymous Coward
    NASA scientists unveiled the first consistent and continuous global measurements of Webchat's "user metabolism."

    Data from the kc and Thunderwoman satellites are helping scientists frequently update maps of the rate at which luser life on Webchat is absorbing abuse and /kill's out of the admins of webchat.

    The rate of luser asphyxiation through ScattKsynthesis is a basic property of life on Webchat of ORG. It is the basis for capturing and storing the energy that fuels their ever growing need for assholish

  • Lazy Oceans (Score:1, Funny)

    by rf0 ( 159958 )
    Just sitting there doing nothing? I mean what have they ever done for us :)

    Rus
    • Just like your mom!
    • Not very lazy at all according to the article: "When you average the productivity rates over the whole world, the ocean is roughly equal to the land." - Wayne Esaias, biological oceanographer at NASA's Goddard Space Flight Center

    • Re:Lazy Oceans (Score:2, Interesting)

      by matt_morgan ( 220418 )

      The Oceans are probably a buffered carbon dioxide sink. A LOT of climate research goes into the topic of how much CO2 they contain, and how much more they might contain.

      For example, CO2 appears not to be increasing in the atmosphere as fast as it should be, given increased emissions. One likely carbon sink may be forests--that is, maybe production in forests increases when CO2 availability increases. However, many people doubt that forests are CO2-limited in terms of their growth. More likely, there's

    • I know you are joking, but if you read the article, it says that despite the low production levels in ocean areas, due to the very large area of the oceans they actually are about even with land in total production.

  • Carbon Budget (Score:2, Insightful)

    by SEWilco ( 27983 )
    That's a nice picture of plant activity. Now if the carbon budget could get balanced, so we know how much carbon is going where... and NASA may have a little difficulty measuring how much is landing on the ocean bottom.

    Oh, why does it matter? If more carbon is being removed by the carbon cycle than is being released -- we'll run out of carbon dioxide. No plant respiration. No oxygen production.

    • But there would be lots of happy bacteria munching on all those dead plans, turning them back into carbon dioxide. The Earth's biosphere (in the long term) stabilizes the global climate.
    • Oh, why does it matter? If more carbon is being removed by the carbon cycle than is being released -- we'll run out of carbon dioxide. No plant respiration. No oxygen production.

      Long before we run out of carbon dioxide the climate of the Earth would probably get MUCH colder, reducing the amount of photosynthesis occurring. I'm not sure if a causal relationship has tuly been established, but it has been observed in many paleoclimate studies that higher oxygen levels (and lower carbon dioxide levels) are

      • Somewhat colder. Water vapor provides 70% of the greenhouse effect, so carbon dioxide contributes less than 30%.

        Do those paleoclimate studies only detect higher oxygen levels, or also detect lower carbon dioxide levels? The two are not totally interdependent, there is a lot more of both available, and a lot more of both could get removed independently of each other. For example, a volcanic eruption could emit a lot of iron which then absorbs oxygen. Or look at the Himalayas, whose new rocks are suckin


  • I'm not trying to be critical here, but I do not completely believe this data. Its given to us in an incredibly misleading way. They are essentially telling us that every square foot of the planet produces more CO2 than O2 which is simply not possible. There's no mapping of negative production, so it looks like we're spiralling out of control.
    • it looks like we're spiralling out of control

      Were you still doubting it?
      • http://earthobservatory.nasa.gov/Newsroom/NPP/Ima g es/psn.modis.200212.900x450.jpg

        In December there is 0 kgC/km^2 generated in the US?

        There's something I think a lot of people are missing here. This map is showing the Carbon produced when it is stripped away from an Oxygen molecule. It does not reflect the amount of CO2 in the atmosphere at a given time. This is the reason why the Hemisphere that is in Summer is so colorful and explains the reason why the Ocean is purple... because its constantly conv
    • Fosil fuels. They produce CO2 and are why the numbers don't "balance".
      • Yes, but according to the map, every piece of land including bumble-fuck Canada and South America are producing CO2. Even over the ocean according to this map there is C02 production, even though the absorption is greater b/c there is no production.
    • These data are merely a measure of the "carbon fixing" of vegetation: the amount of carbon from the atmosphere used by plants to make bigger plants. The alogorithm is based on the photosynthesis activity of plants. It doesn't include the carbon released back into the atmosphere after a fire, or the carbon dioxide emitted from rotting vegetation (I'm almost positive about the second one, but haven't been able to get in touch with the principal investigator). We (the scientific community & NASA) are still
    • This is measuring "productivity" -- how much CO2 is being altered to O2 while the plants produce sugars. Only living carbon sinks are shown, so the geologic sinks which remove carbon for a long time (ocean floor) are not shown. The carbon sources also are not shown, so it is not showing when a tree rots in a wet forest and releases methane and soil (there are other satellite images [nasa.gov] which do show vegetation fire patterns).

  • Global Warming? (Score:1, Offtopic)

    by petronivs ( 633683 )
    I'm really surprised no one's started a serious global warming flame. really.

  • The Oceans (Score:5, Interesting)

    by jolyonr ( 560227 ) on Friday April 25, 2003 @08:30AM (#5807623) Homepage
    It's quite interesting to see how much carbon is being soaked up by the oceans. Much of this carbon eventually ends up as deposits on the sea floor and, after millions of years, limestone. It may be a lower amount of carbon intake than the forests, but then forest fires and biological action on dead trees can eventually release a percentage of the carbon that's trapped by trees.
    • THere wa san artile a while ago, about how Mt. everest and the mountains around it changed the climate. Basically, sicne its bare rock and limestone, unlike most smaller mountains which have tress, and grass, it basically soaks co2 out of the air by reactin with the carbonic acid in the rain and neutralisning it, and the neutral salts get washed into the ocean where they settle out. WHat i just said may be completely technically wrong, i am not a chemist, but thats more or less the mechanism, new big asse
  • Look at those black spots in the ocean! Wouldn't it be great to put some floating islands there and plant lots and lots of trees. And bring up cold water from the deeper layers so that plankton could start growing and feed the fish and the whales. Impossible? Oh well; it was a nice dream.
  • . . . check out the following links:

    MODIS Web [nasa.gov] MODIS and MODIS links [nasa.gov]

  • Do we start burning bed rock instead? What about geotherms from the earth's magma. Why can't we use it (they do in Iceland) as a carbon substitute.
    • What about geotherms from the earth's magma. Why can't we use it (they do in Iceland) as a carbon substitute.

      Most places don't have access to the abundant geothermal energy that Iceland has access to, located on a spreading center as it is. Spreading centers (places where two plates are moving away from eachother, creating new crust) bring magma very close to the surface of the Earth, much closer than pretty much anywhere else (except volcanoes, but those are a little tricky to harness the thermal energ

      • Why not make iceland the place for an electric earth. Put powerlines in the sea and bring current that way to other places. Same thing with nuclear power. Nobody wants a nuclear power plant next door, I don't either. So build a nuclear power plant in the arctic region or wyoming dessert that nobody cares about, and make powerlines that circle the earth.
        • Probably for cost reasons, and transmission losses. It would probably be much easier for PG&E (or any other power produciton company) to locate all of their power generation in one place for ease of service and management, but the fact is they would be losing a large amount of energy in transmitting that energy over long distances.
  • I think I'll go take a shit in the woods, and go piss on a tree. One less "WHOOSH..." down the toilet. Hey, it saves water, and that water could be donated to some squirel or a starving person in Ethiopia or some other equally tree huging manuever! Happy Earth day slashdot!
  • There were times when eco-nuts blamed burping cows for excess carbon in the form burping and farting methane. This would probably show up as carbon excess in the west US and sourthern south america, if this hypothesis is true. Looks of cows and few trees in those regions.

  • No - graphics are mislabeled; some npp numbers (Score:1, Insightful)

    by Anonymous Coward
    Come on folks. Most of vegitation dry weight is carbon. If it took a square kilometer to fix a kilogram of carbon each year... well, leaf raking would be sooo much easier. The units should probably be kgC per square meter per year. But what's a 6 order of magnitude error between friends. Got to love NASA PR.

    Earth's surface as a 20 x 25 Megameter rectangle [vendian.org] has some old npp numbers from John Harte's "Consider a Spherical Cow". (I would have inlined them here, but I can't seem to do a PRE tag...) Goog

  • Geeky SIde of NPP Calculation. (Score:3, Interesting)

    by JungleBoy ( 7578 ) on Friday April 25, 2003 @11:28AM (#5808965)

    The Land NPP algorithm was developed at the NTSG [umt.edu] at the University of Montana [umt.edu]. I am the Sys Admin for this group.

    We developed the software to do the Gross and Net primary productivity calculations (as well as some others), but the main production runs are done at the Goddard Space Flight Center in a room full of SGI Origin servers. Our development environment consists of several smallish linux beowulf clusters (32x1Ghz P3), a few Althon MP boxes, some old AIX dev boxes, and one SGI Oxygen for nasa code certification. Our largest resource is disk space, we have about 12TB of capacity. Keep in mind that this is just for algorithm development and testing. Goddard's production facility is huge, but that's becuase they are producing tons of other data products as well including all the land, ocean, and atmospheric products off of both the Terra [nasa.gov] and Aqua [nasa.gov] Satellites. This land productivity data (MOD17 in nasa speak) is derived in part from the MODIS [nasa.gov] sensor on Terra.

    Both of these satellites are in sun syncronous polar orbits meaning that they come down over the earth's day side. This is because many of the sensors (like MODIS) are passive. Terra is the 'AM' satellite, it crosses the equator about mid morning local time, and Aqua being the 'PM' satellite crosses in the afternoon. The reason for this is because there is a significance in AM and PM cloud cover. Cloud cover is difficult to correct for (in fact with MODIS, sometimes you can't correct).


    -JungleBoy (aka tweaker)
    Melt our server room Axis Camera [umt.edu]
    Automated GPP Images Site (in devel) [umt.edu]
    My Lame Website. [tweaker.tv]
  • Check out the website I work on,
    http://Coastwatch.noaa.gov .
    (There is a search interface at http://coastwatch.noaa.gov/interface/interface.htm l)
    We do near real time processing of Modis data and a host of other satellites. MODIS is a joint operation between NOAA & NASA.

  • Actually the biggest problem with carbon is that it can be released by methane that is being stored in the ocean. The way to cause that methane to release carbon 12 is by a 4-5 degrees global temperature increase.

    All the carbon 12 that is being released could cause an additional 4-5 degrees of temperature increase.

    10 degrees of global temperature increase could turn England into a desert. It has been proved that this phenomenon caused a pre-dinosaur extinction of about almost all life on earth. (The Permi
    • Why just Carbon 12? Very few things hold onto (or release) C12 selectively over C14 or any other form of carbon, and they have the same large-scale effects. Was it just to make the comment sound more science-like (I would definitely believe that, especially if you picked this up from Discovery)? Oh, and no cause of the Permian extinction (or any other mass extinction in the past) has been proven. The explanation you mentioned may just happen to be the theory that currently fits the data best, but it is
      • They found high concentrations of C12 around the fossils from that period. The only way they could produce high amounts of C12 was through methane in water at a higher temperature.
        The really interesting idea is that how only a slight change in temperature increase can trigger so many other events that added up would cause a catastrophic event.
        They have tested many other hypotheses like massive meteor impacts that could cause the earth to "bleed" by releasing a lot of lava but all of them failed.

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