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Earth's permafrost starts to squelch

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  • Sonya
    Earth s permafrost starts to squelch By Molly Bentley in San Francisco snips..... Alaska is not the only region in a slump. The permafrost melt is
    Message 1 of 4 , Jan 1, 2005
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      Earth's permafrost starts to squelch By Molly Bentley in San Francisco
      snips..... Alaska is not the only region in a slump. The permafrost melt
      is accelerating throughout the world's cold regions, scientists reported
      at the recent Fall Meeting of the American Geophysical Union (AGU) in
      San Francisco. In addition to northern Alaska, the permafrost zone
      includes most other Arctic land, such as northern Canada and much of
      Siberia, as well as the higher reaches of mountainous regions such as
      the Alps and Tibet. All report permafrost thaw. Will the Arctic be a
      carbon sink, or convert to a carbon source? It's a big unknown Frederick
      Nelson, University of Delaware "It's a very, very widespread problem,"
      said Frederick Nelson, a geographer at the University of Delaware, US.
      Scientists attribute the thaw to climate warming. As the air temperature
      warms, so does the frozen ground beneath it.
      http://news.bbc.co.uk/2/hi/science/nature/4120755.stm


      snip ......But not all outcomes of permafrost thaw have precedent, or an
      immediate solution. One considerable variable is the possible release
      into the air of organic carbon stored in the permafrost. In the drier
      areas, most of the emissions would be in the form of carbon dioxide
      (CO2). But in the wetter areas, it would be methane, a more effective
      greenhouse gas. Scientists do not know exactly how much carbon is
      sequestered in the permafrost regions, but estimates show it could be up
      to a quarter of the sequestered carbon on Earth, 14% of it in the
      Arctic, alone. "Will the Arctic be a carbon sink, or convert to a carbon
      source?" posed Dr Nelson. "It's a big unknown."
      http://news.bbc.co.uk/2/hi/science/nature/4120755.stm

      From the Fall 2004 AGU meeting search page.........
      http://www.agu.org/cgi-bin/SFgate/SFgate.

      0800h AN: C41A-0192
      TI: Amplified carbon release from vast West Siberian peatlands by 2100
      AU: * Frey, K E EM: frey@... AF: University of California, Los
      Angeles, Dept. of Geography, Los Angeles, CA 90095 United States
      AU: Smith, L C EM: lsmith@... AF: University of California,
      Los Angeles, Dept. of Geography, Los Angeles, CA 90095 United States
      AU: Smith, L C EM: lsmith@... AF: University of California,
      Los Angeles, Dept. of Earth and Space Sciences, Los Angeles, CA 90095
      United States

      AB: The potential impacts of climate change on peatland carbon cycling
      are subject to ongoing debate. Since the Last Glacial Maximum, northern
      peatlands have behaved primarily as a net sink of atmospheric carbon,
      storing up to $\sim$455 Pg C or one-third of the global soil carbon
      pool. However, the likely fate of this carbon under a warming climate
      remains a major unanswered question in Arctic Science and is
      particularly relevant in West Siberia, which contains the world's
      largest stores of peat carbon, exports massive volumes of freshwater and
      dissolved organic carbon (DOC) to the Arctic Ocean, and is warming
      faster than the Arctic as a whole. Here we present extensive DOC
      measurements from 96 watersheds distributed throughout West Siberia,
      providing data on a much larger spatial scale than previous studies and
      for the first time explicitly examining stream DOC in permafrost
      environments. Our results show cold, permafrost-influenced watersheds
      release little DOC to streams. However, we find drastically higher
      values in warm, permafrost-free watersheds, rising as a function of
      peatland abundance. The two regimes are demarcated by the position of
      the -$2\deg$C air temperature isotherm, which is also approximately
      coincident with the permafrost boundary. Climate models predict
      near-doubling of these warm areas in West Siberia by 2100, suggesting up
      to 700$%$ increases in stream DOC concentrations and 2.7-4.3 Tg
      yr$^{-1}$ increases in DOC flux from the region.
      =============================================
      B13C-0246
      TI: Methane Climate Forcing and Methane Release in the Siberian
      Fresh-Water Systems and Marine Ecosystems.
      AU: * Shakhova, N EM: nshakhov@...
      AF: International Arctic Research Center, UAF, 930 Koyukuk Dr.,
      Fairbanks, AK 99775 United States
      AU: Semiletov, I EM: igorsm@... AF: Pacific Institute of
      Geography, Russian Academy of Sciences, 5 Radio St., Vladivostok, 690041
      Russian Federation AU: Romanovsky, V EM: ffver@... AF: International
      Arctic Research Center, UAF, 930 Koyukuk Dr., Fairbanks, AK 99775 United
      States

      AB: Surface water is a significant part of the Arctic coastal plain
      landscape, comprising up to 50-80 percent of the land area. In general,
      Arctic coastal lakes and sea lagoons are thermokarst or thaw by origin.
      Zones of thawed permafrost called taliks underlie deeper lake and lagoon
      sediments. Thaw lakes have migrated across the coastal plains during the
      Holocene (and previous warm epochs), and their concentrations and depth
      has increased with warmer conditions. Warming increases permafrost
      thawing and vast organic reservoirs immobilized in permafrost become
      available for anaerobic destruction through lake growth, migration and
      developing into sea lagoons. Due to these processes a huge amount of
      methane releases from fresh-water and shallow marine ecosystems. It
      might contributes significantly in formation the maximum atmospheric
      methane over the Arctic exceeds that over Antarctica in wintertime by
      8-10 percent. Our direct wintertime methane flux measurements from
      northern lakes demonstrate that wintertime income of methane provided by
      them is essential enough to be supposed as underestimated regional
      wintertime source of methane, because of far less sinks available to
      balance in winter. As taliks can be through permafrost, another source
      of atmospheric methane year-round can be associated with disturbance of
      the sub-sea hydrates. In this report we present the data concerning
      typical Arctic Siberian lakes, shallow zone of the Laptev and
      East-Siberian seas.
      ==========================
      C53A-03 INVITED
      TI: Are Increasing Freshwater Inputs To The Arctic Ocean Linked To
      Climate Change?
      AU: * Peterson, B J EM: peterson@...
      AF: The Ecosystems Center Marine Biological Laboratory, 7 MBL Street,
      Woods Hole, MA 02543 United States
      AU: Holmes, R M EM: rholmes@... AF: The Ecosystems Center Marine
      Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543 United States
      AU: McClelland, J W EM: jmcclelland@...
      AF: The Ecosystems Center Marine Biological Laboratory, 7 MBL Street,
      Woods Hole, MA 02543 United States
      AU: Curry, R G EM: rcurry@... AF: Woods Hole Oceanographic
      Institution, MS 21 365 Woods Hole Road, Woods Hole, MA 02543 United States

      AB: The global hydrological cycle has shown evidence of acceleration
      over the past 40 years. Evidence includes increasing evaporation from
      low latitude oceans and increasing precipitation, especially at high
      latitudes. Net melting of arctic glaciers plus runoff from Eurasian
      arctic rivers alone have added about 4000 km$^{3}$ of extra (anomaly
      from baseline conditions) freshwater to the Arctic Ocean since about
      1960. Glacier melt is primarily driven by arctic warming. The Eurasian
      discharge monitoring includes 2/3 of total Eurasian runoff which
      comprises 60% of pan-arctic runoff. An investigation of mechanisms
      driving changes in Eurasian runoff showed that dams, fires and
      permafrost melt were probably not the major factors causing increased
      discharge. The discharge changes appear to be driven by the acceleration
      of the hemispheric hydrologic cycle driven by warming and possibly by
      shifts in wind directions. Over the same 40 years the high latitude
      oceans have freshened. A coordinated effort to reconcile the changes in
      freshwater inputs with changes in freshwater inventory of the Arctic
      Ocean, Nordic Seas and North Atlantic over the past 40-50 years would be
      a valuable contribution.
      =========================================
      GC43A-01 INVITED TI: Arctic Warming Signals From Satellite Observations
      AU: * Comiso, J C EM: josefino.c.comiso@...: NASA Goddard Space
      Flight Center, Oceans and Ice Branche, Code 971, Greenbelt, MD 20771
      United States

      AB: Global warming signals are expected to be amplified in the polar
      regions because of ice-atmosphere feedbacks associated with the high
      reflectivity of the ice and snow that blankets much of the region.
      Analysis of infrared satellite data reveals that the Arctic region has
      been warming at the rate of 0.5 §C per decade since 1981 but large
      spatial variability in the trends are apparent with the most positive
      occurring in North America and the Western Arctic and with some negative
      trends occurring in parts of Russia. During approximately the same
      period, the Arctic perennial ice cover declined at a rapid rate of 9.2 %
      per decade. While large interannual variability in the perennial ice
      area was observed in the 1980s and early 1990s, the perennial ice areas
      from 1998 to 2004 have been abnormally low compared to the average
      perennial ice area during the previous 20 years. Moreover, the length of
      melt temperatures has also been increasing by 13 days per decade over
      sea ice covered areas, suggesting concurrent thinning in the ice cover.
      In other regions, the length of melt has increased by 5 days per decade
      over Greenland, showing consistency with the observed thinning in the
      ice sheets and increasing extent of melt areas. The length of thawing at
      the permafrost areas of North America has also been increasing at 7 days
      per decade, which can be a major concern in inhabited regions.
      Furthermore, the areal extent of the snow cover in the entire Northern
      Hemisphere has been decreasing by about 2.6 % per decade while most
      glaciers in the Arctic region have been declining. The locations of most
      rapid changes are in same general areas as where the surface temperature
      data show considerable warming. The overall impact of aforementioned
      changes in the Arctic region can be profound, especially if the current
      trends continue.
      ===============================================
      C12A-05 INVITED
      TI: Permafrost and Railroad Construction on the Tibetan Plateau
      AU: * Cheng, G EM: gdcheng@...: State Key Laboratory of
      Frozen Soil Engineering, CAREERI, Chinese Academy of Sciences, Lanzhou,
      730000 China AU: Zhang, T EM: tzhang@...: National Snow and Ice
      Data Center, NSIDC/CIRES, 449 UCB University of Colorado, Boulder, CO
      80309-0449 United States

      AB: The Qinghai-Xizang railroad is under construction on "The Roof of
      the World" --- the Tibetan Plateau, to be completed in 2007. The
      railroad will cross 550 km of permafrost region over the Tibetan
      Plateau, 50% of which is high-temperature permafrost and 37% of which is
      ice-rich permafrost. Predicted climate warming over the Tibetan Plateau
      in the coming decades would accelerate permafrost degradation. Surface
      disturbance due to the railroad construction would further destabilize
      permafrost conditions and seriously damage the ecosystem in the
      permafrost region. Thawing of warm permafrost over the Tibetan Plateau
      becomes one of the key issues in the cross-Plateau railroad
      construction. In this presentation, we will discuss techniques used to
      prevent permafrost from thawing due both to the climate warming and the
      surface disturbance of engineering construction. Although several
      techniques have been used over the Tibetan Plateau, application of
      crushed rock layer to cool permafrost and maintain permafrost stability
      is very successful at current stage although further observations are
      needed. We will also further demonstrate the principles of using the
      crushed rock layer to maintain permafrost based on data from field
      investigation, laboratory experiments, and numerical simulations.
      .

      --
      Sonya PLoS Medicine
      The open-access general medical journal from the Public Library of Science
      Inaugural issue: Autumn 2004 Share your discoveries with the world.
      http://www.plosmedicine.org
    • Randy Mott
      I posted some stuff on this topic earlier, that indicated from actuall testing that the carbon sink function accelerated, not the other weay around. I will
      Message 2 of 4 , Jan 3, 2005
      • 0 Attachment
        I posted some stuff on this topic earlier, that indicated
        from actuall testing that the carbon sink function
        accelerated, not the other weay around. I will look
        again...

        Randy

        --- Sonya <msredsonya@...> wrote:

        > Earth's permafrost starts to squelch By Molly Bentley in
        > San Francisco
        > snips..... Alaska is not the only region in a slump. The
        > permafrost melt
        > is accelerating throughout the world's cold regions,
        > scientists reported
        > at the recent Fall Meeting of the American Geophysical
        > Union (AGU) in
        > San Francisco. In addition to northern Alaska, the
        > permafrost zone
        > includes most other Arctic land, such as northern Canada
        > and much of
        > Siberia, as well as the higher reaches of mountainous
        > regions such as
        > the Alps and Tibet. All report permafrost thaw. Will
        > the Arctic be a
        > carbon sink, or convert to a carbon source? It's a big
        > unknown Frederick
        > Nelson, University of Delaware "It's a very, very
        > widespread problem,"
        > said Frederick Nelson, a geographer at the University of
        > Delaware, US.
        > Scientists attribute the thaw to climate warming. As the
        > air temperature
        > warms, so does the frozen ground beneath it.
        > http://news.bbc.co.uk/2/hi/science/nature/4120755.stm
        >
        >
        > snip ......But not all outcomes of permafrost thaw have
        > precedent, or an
        > immediate solution. One considerable variable is the
        > possible release
        > into the air of organic carbon stored in the permafrost.
        > In the drier
        > areas, most of the emissions would be in the form of
        > carbon dioxide
        > (CO2). But in the wetter areas, it would be methane, a
        > more effective
        > greenhouse gas. Scientists do not know exactly how much
        > carbon is
        > sequestered in the permafrost regions, but estimates show
        > it could be up
        > to a quarter of the sequestered carbon on Earth, 14% of
        > it in the
        > Arctic, alone. "Will the Arctic be a carbon sink, or
        > convert to a carbon
        > source?" posed Dr Nelson. "It's a big unknown."
        > http://news.bbc.co.uk/2/hi/science/nature/4120755.stm
        >
        > From the Fall 2004 AGU meeting search page.........
        > http://www.agu.org/cgi-bin/SFgate/SFgate.
        >
        > 0800h AN: C41A-0192
        > TI: Amplified carbon release from vast West Siberian
        > peatlands by 2100
        > AU: * Frey, K E EM: frey@... AF: University of
        > California, Los
        > Angeles, Dept. of Geography, Los Angeles, CA 90095 United
        > States
        > AU: Smith, L C EM: lsmith@... AF: University of
        > California,
        > Los Angeles, Dept. of Geography, Los Angeles, CA 90095
        > United States
        > AU: Smith, L C EM: lsmith@... AF: University of
        > California,
        > Los Angeles, Dept. of Earth and Space Sciences, Los
        > Angeles, CA 90095
        > United States
        >
        > AB: The potential impacts of climate change on peatland
        > carbon cycling
        > are subject to ongoing debate. Since the Last Glacial
        > Maximum, northern
        > peatlands have behaved primarily as a net sink of
        > atmospheric carbon,
        > storing up to $\sim$455 Pg C or one-third of the global
        > soil carbon
        > pool. However, the likely fate of this carbon under a
        > warming climate
        > remains a major unanswered question in Arctic Science and
        > is
        > particularly relevant in West Siberia, which contains the
        > world's
        > largest stores of peat carbon, exports massive volumes of
        > freshwater and
        > dissolved organic carbon (DOC) to the Arctic Ocean, and
        > is warming
        > faster than the Arctic as a whole. Here we present
        > extensive DOC
        > measurements from 96 watersheds distributed throughout
        > West Siberia,
        > providing data on a much larger spatial scale than
        > previous studies and
        > for the first time explicitly examining stream DOC in
        > permafrost
        > environments. Our results show cold,
        > permafrost-influenced watersheds
        > release little DOC to streams. However, we find
        > drastically higher
        > values in warm, permafrost-free watersheds, rising as a
        > function of
        > peatland abundance. The two regimes are demarcated by the
        > position of
        > the -$2\deg$C air temperature isotherm, which is also
        > approximately
        > coincident with the permafrost boundary. Climate models
        > predict
        > near-doubling of these warm areas in West Siberia by
        > 2100, suggesting up
        > to 700$%$ increases in stream DOC concentrations and
        > 2.7-4.3 Tg
        > yr$^{-1}$ increases in DOC flux from the region.
        > =============================================
        > B13C-0246
        > TI: Methane Climate Forcing and Methane Release in the
        > Siberian
        > Fresh-Water Systems and Marine Ecosystems.
        > AU: * Shakhova, N EM: nshakhov@...
        > AF: International Arctic Research Center, UAF, 930
        > Koyukuk Dr.,
        > Fairbanks, AK 99775 United States
        > AU: Semiletov, I EM: igorsm@... AF: Pacific
        > Institute of
        > Geography, Russian Academy of Sciences, 5 Radio St.,
        > Vladivostok, 690041
        > Russian Federation AU: Romanovsky, V EM: ffver@...
        > AF: International
        > Arctic Research Center, UAF, 930 Koyukuk Dr., Fairbanks,
        > AK 99775 United
        > States
        >
        > AB: Surface water is a significant part of the Arctic
        > coastal plain
        > landscape, comprising up to 50-80 percent of the land
        > area. In general,
        > Arctic coastal lakes and sea lagoons are thermokarst or
        > thaw by origin.
        > Zones of thawed permafrost called taliks underlie deeper
        > lake and lagoon
        > sediments. Thaw lakes have migrated across the coastal
        > plains during the
        > Holocene (and previous warm epochs), and their
        > concentrations and depth
        > has increased with warmer conditions. Warming increases
        > permafrost
        > thawing and vast organic reservoirs immobilized in
        > permafrost become
        > available for anaerobic destruction through lake growth,
        > migration and
        > developing into sea lagoons. Due to these processes a
        > huge amount of
        > methane releases from fresh-water and shallow marine
        > ecosystems. It
        > might contributes significantly in formation the maximum
        > atmospheric
        > methane over the Arctic exceeds that over Antarctica in
        > wintertime by
        > 8-10 percent. Our direct wintertime methane flux
        > measurements from
        > northern lakes demonstrate that wintertime income of
        > methane provided by
        > them is essential enough to be supposed as underestimated
        > regional
        > wintertime source of methane, because of far less sinks
        > available to
        > balance in winter. As taliks can be through permafrost,
        > another source
        > of atmospheric methane year-round can be associated with
        > disturbance of
        > the sub-sea hydrates. In this report we present the data
        > concerning
        > typical Arctic Siberian lakes, shallow zone of the Laptev
        > and
        > East-Siberian seas.
        > ==========================
        > C53A-03 INVITED
        > TI: Are Increasing Freshwater Inputs To The Arctic Ocean
        > Linked To
        > Climate Change?
        > AU: * Peterson, B J EM: peterson@...
        > AF: The Ecosystems Center Marine Biological Laboratory, 7
        > MBL Street,
        > Woods Hole, MA 02543 United States
        > AU: Holmes, R M EM: rholmes@... AF: The Ecosystems
        > Center Marine
        > Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543
        > United States
        > AU: McClelland, J W EM: jmcclelland@...
        > AF: The Ecosystems Center Marine Biological Laboratory, 7
        > MBL Street,
        > Woods Hole, MA 02543 United States
        > AU: Curry, R G EM: rcurry@... AF: Woods Hole
        > Oceanographic
        > Institution, MS 21 365 Woods Hole Road, Woods Hole, MA
        > 02543 United States
        >
        > AB: The global hydrological cycle has shown evidence of
        > acceleration
        > over the past 40 years. Evidence includes increasing
        > evaporation from
        > low latitude oceans and increasing precipitation,
        > especially at high
        > latitudes. Net melting of arctic glaciers plus runoff
        > from Eurasian
        > arctic rivers alone have added about 4000 km$^{3}$ of
        > extra (anomaly
        > from baseline conditions) freshwater to the Arctic Ocean
        > since about
        > 1960. Glacier melt is primarily driven by arctic warming.
        > The Eurasian
        > discharge monitoring includes 2/3 of total Eurasian
        > runoff which
        > comprises 60% of pan-arctic runoff. An investigation of
        > mechanisms
        > driving changes in Eurasian runoff showed that dams,
        > fires and
        > permafrost melt were probably not the major factors
        > causing increased
        > discharge. The discharge changes appear to be driven by
        > the acceleration
        > of the hemispheric hydrologic cycle driven by warming and
        > possibly by
        > shifts in wind directions. Over the same 40 years the
        > high latitude
        > oceans have freshened. A coordinated effort to reconcile
        > the changes in
        > freshwater inputs with changes in freshwater inventory of
        > the Arctic
        > Ocean, Nordic Seas and North Atlantic over the past 40-50
        > years would be
        > a valuable contribution.
        > =========================================
        > GC43A-01 INVITED TI: Arctic Warming Signals From
        > Satellite Observations
        > AU: * Comiso, J C EM: josefino.c.comiso@...: NASA
        > Goddard Space
        > Flight Center, Oceans and Ice Branche, Code 971,
        > Greenbelt, MD 20771
        > United States
        >
        > AB: Global warming signals are expected to be amplified
        > in the polar
        > regions because of ice-atmosphere feedbacks associated
        > with the high
        > reflectivity of the ice and snow that blankets much of
        > the region.
        > Analysis of infrared satellite data reveals that the
        > Arctic region has
        > been warming at the rate of 0.5 �C per decade since 1981
        > but large
        > spatial variability in the trends are apparent with the
        > most positive
        > occurring in North America and the Western Arctic and
        > with some negative
        > trends occurring in parts of Russia. During approximately
        > the same
        > period, the Arctic perennial ice cover declined at a
        > rapid rate of 9.2 %
        > per decade. While large interannual variability in the
        > perennial ice
        > area was observed in the 1980s and early 1990s, the
        > perennial ice areas
        > from 1998 to 2004 have been abnormally low compared to
        > the average
        > perennial ice area during the previous 20 years.
        > Moreover, the length of
        > melt temperatures has also been increasing by 13 days per
        > decade over
        > sea ice covered areas, suggesting concurrent thinning in
        > the ice cover.
        > In other regions, the length of melt has increased by 5
        > days per decade
        > over Greenland, showing consistency with the observed
        > thinning in the
        > ice sheets and increasing extent of melt areas. The
        > length of thawing at
        > the permafrost areas of North America has also been
        > increasing at 7 days
        > per decade, which can be a major concern in inhabited
        > regions.
        > Furthermore, the areal extent of the snow cover in the
        > entire Northern
        > Hemisphere has been decreasing by about 2.6 % per decade
        > while most
        > glaciers in the Arctic region have been declining. The
        > locations of most
        > rapid changes are in same general areas as where the
        > surface temperature
        > data show considerable warming. The overall impact of
        > aforementioned
        > changes in the Arctic region can be profound, especially
        > if the current
        > trends continue.
        > ===============================================
        > C12A-05 INVITED
        > TI: Permafrost and Railroad Construction on the Tibetan
        > Plateau
        > AU: * Cheng, G EM: gdcheng@...: State Key
        > Laboratory of
        > Frozen Soil Engineering, CAREERI, Chinese Academy of
        > Sciences, Lanzhou,
        > 730000 China AU: Zhang, T EM: tzhang@...:
        > National Snow and Ice
        > Data Center, NSIDC/CIRES, 449 UCB University of Colorado,
        > Boulder, CO
        > 80309-0449 United States
        >
        > AB: The Qinghai-Xizang railroad is under construction on
        > "The Roof of
        > the World" --- the Tibetan Plateau, to be completed in
        > 2007. The
        > railroad will cross 550 km of permafrost region over the
        > Tibetan
        > Plateau, 50% of which is high-temperature permafrost and
        > 37% of which is
        > ice-rich permafrost. Predicted climate warming over the
        > Tibetan Plateau
        > in the coming decades would accelerate permafrost
        > degradation. Surface
        > disturbance due to the railroad construction would
        > further destabilize
        > permafrost conditions and seriously damage the ecosystem
        > in the
        > permafrost region. Thawing of warm permafrost over the
        > Tibetan Plateau
        > becomes one of the key issues in the cross-Plateau
        > railroad
        > construction. In this presentation, we will discuss
        > techniques used to
        > prevent permafrost from thawing due both to the climate
        > warming and the
        > surface disturbance of engineering construction. Although
        > several
        > techniques have been used over the Tibetan Plateau,
        > application of
        > crushed rock layer to cool permafrost and maintain
        > permafrost stability
        > is very successful at current stage although further
        > observations are
        > needed. We will also further demonstrate the principles
        > of using the
        > crushed rock layer to maintain permafrost based on data
        > from field
        > investigation, laboratory experiments, and numerical
        > simulations.
        > .
        >
        > --
        > Sonya PLoS Medicine
        > The open-access general medical journal from the Public
        > Library of Science
        > Inaugural issue: Autumn 2004 Share your discoveries
        > with the world.
        > http://www.plosmedicine.org
        >
        >


        =====
        Randy M. Mott
        President
        EkoTechnology Sp. z o.o
        Warsaw, Poland
        48- 0 - 691-712 716
        48-22- 644 9623
        randymott@...



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      • Sonya
        Randy wrote ......... I posted some stuff on this topic earlier, that indicated from actuall testing that the carbon sink function accelerated, not
        Message 3 of 4 , Jan 4, 2005
        • 0 Attachment
          Randy wrote ......... I posted some stuff on this topic earlier,
          that indicated from actuall testing that the carbon sink function
          accelerated, not theother weay around. I will look
          again...

          Sonya replies."""> actuall testing that the carbon sink function
          accelerated, not theother weay around""
          are you stating that increased heat would raise the chances of the
          carbon being retained? The only way that I know the word sink to be
          used is in relation to storage and the only reports that I have read
          that would be somewhat similar in that sort of take, would reports that
          put forward that soil, not permafrost, that soil initially will release
          carbon stores upon exposure to heat, but at some point down the line,
          will recover...........

          The abstracts I posted where derived from Dec 2004
          Fall AGU meeting, not very dated in presentation, in date of work,
          perhaps.......that aside.....it should be interesting the
          science and statistical standards/methodology behind any reports stance
          that "actuall testing that the carbon sink function accelerated, not the
          other weay around. I will look again..."

          Thank you for looking, no rush, but thanks just the same...........Sonya

          Not sure if you have seen reports postulating a link in ozone loss
          advocated
          as another source of releasing methane CH4 from current sinks (not
          mentioned often).....

          Report 103. Past and Future Effects of Ozone on Net Primary Production
          and Carbon Sequestration Using a Global Biogeochemical Model [PDF
          <MITJPSPGC_Rpt103.pdf>: 1.4 MB]

          B. Felzer, J. Reilly, J. Melillo, D. Kicklighter, C. Wang, R. Prinn, M.
          Sarofim & Q. Zhuang October 2003 [Revised January 2004] (27 p.)
          Exposure of plants to ozone inhibits photosynthesis and therefore
          reduces vegetation production and carbon sequestration. Simulations with
          the Terrestrial Ecosystem Model (TEM) for the historical period
          (1860-1995) show the largest damages occur in the eastern U.S., Europe,
          and eastern China, with reductions in Net Primary Production (NPP) of
          over 70% for some locations. Scenarios through the year 2100 using the
          MIT Integrated Global Systems Model (IGSM) show potentially greater
          negative effects in the future. In the worst-case scenario, the current
          land carbon sink in China could become a carbon source. Reduced crop
          yields resulting from ozone damage are potentially large but can be
          mitigated by controlling emissions of ozone precursors. Failure to
          consider ozone damages to vegetation would by itself raise the costs
          over the next century of stabilizing atmospheric concentrations of CO2
          by 3 to 18%. But, climate policy would also reduce ozone precursor
          emissions, and ozone, and these additional benefits are estimated to be
          between 4 and 21% of the cost of the climate policy. Tropospheric ozone
          effects on terrestrial ecosystems thus produce a surprisingly large
          feedback in estimating climate policy costs that, heretofore, has not
          been included in cost estimates.
          ===========================================================
          Report 90. Ozone Effects on Net Primary Production and Carbon
          Sequestration in the Conterminous United States Using a Biogeochemistry
          Model [PDF <MITJPSPGC_Rpt90.pdf>: 560 kB]
          B.S. Felzer, D.W. Kicklighter, J.M. Melillo, C. Wang, Q. Zhuang & R.G.
          Prinn November 2002 (23 p.)
          The effects of air pollution on vegetation may provide an important
          control on the carbon cycle that has not yet been widely considered.
          Prolonged exposure to high levels of ozone, in particular, has been
          observed to inhibit photosynthesis by direct cellular damage within the
          leaves and through changes in stomatal conductance. We have incorporated
          empirical equations derived for trees (hardwoods and pines) and crops
          into the Terrestrial Ecosystem Model version 4.3 (TEM 4.3) to explore
          the effects of ozone on net primary production and carbon sequestration
          across the conterminous United States. Our results show up to a 5%
          reduction in Net Primary Production (NPP) in response to modeled
          historical ozone levels during the late 1980s to early 1990s. The
          largest decreases (over 20% in some locations) occur in the eastern U.S.
          and Midwest, during months with high ozone levels and high productivity.
          Carbon sequestration during the 1980s is reduced by 30 to 70 Tg C/yr
          with the presence of ozone, or 5 to 23% of recent estimates of the total
          carbon sequestration for the U.S. Thus the effects of ozone on NPP and
          carbon sequestration should be factored into future calculations of the
          U.S. carbon budget.

          Full article
          http://ecosystems.mbl.edu/staffweb/bfelzer/files/mitjpspgc_reprint04-5.pdf
          --
          Sonya PLoS Medicine
          The open-access general medical journal from the Public Library of Science
          Inaugural issue: Autumn 2004 Share your discoveries with the world.
          http://www.plosmedicine.org
        • Tim Jones
          Earth s permafrost starts to squelch By Molly Bentley in San Francisco Last Updated: Wednesday, 29
          Message 4 of 4 , Dec 7, 2005
          • 0 Attachment
            Earth's permafrost starts to squelch
            <http://news.bbc.co.uk/2/hi/science/nature/4120755.stm>
            By Molly Bentley
            in San Francisco
            Last Updated: Wednesday, 29 December, 2004, 01:40 GMT

            In parts of Fairbanks, Alaska, houses and buildings lean at odd angles.

            Some slump as if sliding downhill. Windows and doors inch closer and
            closer to the ground.
            It is an architectural landscape that is becoming more familiar as
            the world's ice-rich permafrost gives way to thaw.

            Water replaces ice and the ground subsides, taking the structures on
            top along with it.

            Alaska is not the only region in a slump. The permafrost melt is
            accelerating throughout the world's cold regions, scientists reported
            at the recent Fall Meeting of the American Geophysical Union (AGU) in
            San Francisco.

            In addition to northern Alaska, the permafrost zone includes most
            other Arctic land, such as northern Canada and much of Siberia, as
            well as the higher reaches of mountainous regions such as the Alps
            and Tibet. All report permafrost thaw.

            Will the Arctic be a carbon sink, or convert to a carbon source?
            It's a big unknown
            Frederick Nelson, University of Delaware

            "It's a very, very widespread problem," said Frederick Nelson, a
            geographer at the University of Delaware, US.

            Scientists attribute the thaw to climate warming. As the air
            temperature warms, so does the frozen ground beneath it.

            Data quest

            The observations reiterate the recent findings of the Arctic Climate
            Impact Assessment report, which attributed the northern polar
            region's summer sea-ice loss and permafrost thaw to dramatic warming
            over the past half-century.
            Thawing permafrost can cause buildings and roads to droop, and
            pipelines to crack.

            Natural features are also affected. Scientists reported an increased
            frequency in landslides in the soil-based permafrost of Canada, and
            an increased instability and slope failures in mountainous regions,
            such as the Alps, where ice is locked in bedrock.

            Click here to see how much Arctic permafrost is projected to
            disappear in the coming decades
            <http://news.bbc.co.uk/nol/shared/spl/hi/pop_ups/05/sci_nat_enl_1104840296/img/1.jpg>

            With the exception of Russia and its long history of permafrost
            monitoring, global records are insufficient - often too brief or
            scattered - to determine the precise extent of ice loss, said Dr
            Nelson.

            However, monitoring programmes that are now much larger in scope,
            such as the Global Terrestrial Network for Permafrost (GTNP),
            indicate a warming trend throughout the permafrost zone.

            Boreholes in Svalbard, Norway, for example, indicate that ground
            temperatures rose 0.4C over the past decade, four times faster than
            they did in the previous century, according to Charles Harris, a
            geologist at the University of Cardiff, UK, and a coordinator of
            Permafrost and Climate in Europe (Pace), which is contributing data
            to the GTNP.

            "What took a century to be achieved in the 20th Century will be
            achieved in 25 years in the 21st Century, if this trend continues,"
            he said.

            Slip and slide

            In Ellesmere Island, Canada, a combination of warmer temperatures and
            sunny days has triggered an increasing frequency of detachment
            events, or landslides, over the past 25 years, compared with the
            previous 75, according to Antoni Lewkowicz, professor of geography at
            the University of Ottawa.

            A detachment event occurs on a slope when the bottom of the active
            layer - the layer of thawing and freezing ground above permafrost -
            becomes slick with melted ice, causing it to slide off from the
            permafrost below.
            But in this case, the amount of temperature increase is not so
            important as the rate of increase, Dr Lewkowicz found.

            Meltwater from ice that warms slowly drains away. When ice warms
            quickly, water pools, creating a frictionless surface between the
            active layer and the permafrost. Like a stroll across a sloping icy
            pavement, a fall is almost certain.

            "We have records from this particular site for about 10 or 12 years,"
            said Dr Lewkowicz. "The years when active layer detachments have
            taken place have been times when we've had this rapid thaw down at
            the bottom of the active layer."

            The slides may cut a wide swath hundreds of metres across, but extend
            only 50 or 60cm deep.

            "They're almost skin-like landslides, moving across the permafrost,"
            said Dr Harris.

            The exposed permafrost, warmed by the air, now produces a new active layer.

            Sink to source

            In steep mountainous regions, permafrost thaw can lead to slope
            failure and rock falls.

            In these areas, the permafrost ice is in hard rock. Where rocks are
            jointed, the ice serves as a kind of cement holding them together.

            When it melts, the rock loses its strength and falls. A dramatic
            example of this occurred during the European heatwave of 2003 when a
            huge block of the Matterhorn broke off suddenly, leaving Alpine
            climbers stranded.

            "It's not just the general warming trend we need to worry about,"
            said Dr Harris, "but these extreme seasonal events as well."

            Dr Nelson says that with human-built structures, proper engineering
            and land use can mitigate permafrost loss.

            Tingjun Zhang, a researcher at the US National Snow and Ice Data
            Center in Boulder, Colorado, reported at the AGU on the particular
            challenge slumping ground presents to the construction of the
            Qinghai-Xizang railway across Tibet, perhaps the most ambitious
            permafrost-zone project since the Trans-Alaskan pipeline.

            Nearly half the railway will lie across permafrost, and temperatures
            in the region are expected to rise during this century.

            Engineers are using a simple - and long established - trick of
            cooling the permafrost with crushed rock. Rocks minimise heat intake
            in summer and promote heat loss in winter.

            It is the first time a large-scale project is using the crushed-rock
            method as its primary solution, according to Dr Zhang.

            But not all outcomes of permafrost thaw have precedent, or an
            immediate solution. One considerable variable is the possible release
            into the air of organic carbon stored in the permafrost.

            In the drier areas, most of the emissions would be in the form of
            carbon dioxide (CO2). But in the wetter areas, it would be methane, a
            more effective greenhouse gas.

            Scientists do not know exactly how much carbon is sequestered in the
            permafrost regions, but estimates show it could be up to a quarter of
            the sequestered carbon on Earth, 14% of it in the Arctic, alone.

            "Will the Arctic be a carbon sink, or convert to a carbon source?"
            posed Dr Nelson. "It's a big unknown."

            Posted by Tim
            AustinTex
            --
            <http://www.groundtruthinvestigations.com/>
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