Arctic Ice, tracking lower than 2008

Discussion in 'Environment' started by Old Rocks, Jul 25, 2009.

  1. Old Rocks
    Online

    Old Rocks Diamond Member

    Joined:
    Oct 31, 2008
    Messages:
    46,466
    Thanks Received:
    5,414
    Trophy Points:
    1,840
    Location:
    Portland, Ore.
    Ratings:
    +10,310
    July 22, 2009
    Arctic sea ice extent tracking below 2008

    Sign up for the Arctic Sea Ice News RSS feed for automatic notification of analysis updates. Updates are also available via Twitter.

    During the first half of July, Arctic sea ice extent declined more quickly than in 2008, but not as fast as in 2007. As in recent years, melt onset was earlier than the 1979 to 2000 average. International sea ice researchers expect another low September minimum ice extent, but they do not yet know if it will fall below the 2007 record.
    Arctic Sea Ice News & Analysis
     
  2. DavidS
    Offline

    DavidS Anti-Tea Party Member

    Joined:
    Sep 7, 2008
    Messages:
    9,811
    Thanks Received:
    766
    Trophy Points:
    48
    Location:
    New York, NY
    Ratings:
    +767
    Oh, can you please tell me how much ice we had in the Arctic during 1975? Or what about 1968? Can you tell me 1955?

    No?

    Oh why is that?

    They've only been tracking ice coverage in the arctic since 1979? You mean, the Earth is 5 billion years old and we're supposed to understand if our ice coverage is normal or abnormal by taking a 30 year sample?

    Are you serious?
     
  3. Big Black Dog
    Offline

    Big Black Dog Gold Member Supporting Member

    Joined:
    May 20, 2009
    Messages:
    22,906
    Thanks Received:
    5,107
    Trophy Points:
    260
    Ratings:
    +5,702
    Pretty warm here today. Wish that Artic ice would hurry up and get here!:lol:
     
  4. Chris
    Offline

    Chris Gold Member

    Joined:
    May 30, 2008
    Messages:
    23,154
    Thanks Received:
    1,958
    Trophy Points:
    205
    Location:
    Virginia
    Ratings:
    +2,089
    40% of the Polar Ice Cap has melted in the last 40 years.

    Yes, it is serious.
     
  5. FactFinder
    Offline

    FactFinder VIP Member

    Joined:
    Mar 1, 2009
    Messages:
    2,641
    Thanks Received:
    202
    Trophy Points:
    83
    Ratings:
    +237
    Perhaps we should have Volcanic Cap & Trade legislation. Tax these rebels into submission.



    Fire Under Arctic Ice: Volcanoes Have Been Blowing Their Tops In The Deep Ocean


    To date, there have been scattered signs of pyroclastic volcanism in the sea, mostly in shallower water depths. Samples of sediment and rock collected on other expeditions have hinted at the possibilities at depths down to 3,000 meters, but the likelihood of explosive eruptions at greater depths seemed slim.

    One reason is the tremendous pressure exerted by the weight of seawater, known as hydrostatic pressure. More importantly, it is very difficult to build up the amount of steam and carbon dioxide gas in the magma that would be required to explode a mass of rock up into the water column. (Far less energy is needed to do so in air.) In fact, the buildup of CO2 in magma in the sea crust would have to be ten times higher than anyone has ever observed in seafloor samples.

    The findings from the Gakkel Ridge expedition appear to show that deep-sea pyroclastic eruptions can and do happen. "The circulation and plumbing of the Gakkel Ridge might be different," said Reves-Sohn. "There must be a lot more volatiles in the system than we thought." The research team hypothesizes that excess gas may be building up like foam or froth near the ceiling of the magma chambers beneath the crust, waiting to pop like champagne beneath a cork.
     
  6. Oddball
    Offline

    Oddball BANNED Supporting Member

    Joined:
    Jan 3, 2009
    Messages:
    41,428
    Thanks Received:
    8,397
    Trophy Points:
    0
    Location:
    Drinking wine, eating cheese, catching rays
    Ratings:
    +8,409
    HERETIC!! :lol:
     
  7. FactFinder
    Offline

    FactFinder VIP Member

    Joined:
    Mar 1, 2009
    Messages:
    2,641
    Thanks Received:
    202
    Trophy Points:
    83
    Ratings:
    +237
    From one of OR's favorite sources:

    Long term trends and changes in the Arctic atmosphere - Walsh

    Much of the Arctic appears to have warmed at the surface over the past 40 years. The warming has been strongest over northern Eurasia and northwestern North America (including Alaska), as shown in the maps at http://faldo.atmos.uiuc.edu/RESEARCH/temptrends.html. The warming has been strongest in winter and spring, when it amounts to as much as 2–3°C per decade since 1960 in the areas of greatest warming. A similar seasonal pattern of warming has been detected in ice station and buoy data from the Arctic Ocean (Serreze et al., 2000). However, much of the warming during this period is likely due less to the greenhouse effect than to changes in the atmospheric circulation. A large-scale pattern of atmospheric pressure and winds, known as the Arctic Oscillation, brings relatively warm air to northern Eurasia and, to a lesser extent, northwestern North America when it is in a particular phase. This phase has been dominant for the past 20 years, while the opposite phase predominated in the 1960s. Hence the changing wind pattern since 1960 has favored warming in the same Arctic areas where the strongest warming has been detected.

    The article adds its obligatory obeyance to AGW but that is obviously speculative. My specualtion is that the shift in wind circulation coupled with the volcanic activity is sufficient to cause greater melting.
     
    Last edited: Jul 26, 2009
  8. Old Rocks
    Online

    Old Rocks Diamond Member

    Joined:
    Oct 31, 2008
    Messages:
    46,466
    Thanks Received:
    5,414
    Trophy Points:
    1,840
    Location:
    Portland, Ore.
    Ratings:
    +10,310
    From the people who discovered the evidence of explosive volcanism at great depth on the Gakkel Ridge.

    News Release : Geologists Discover Signs of Volcanoes Blowing their Tops in the Deep Ocean : Woods Hole Oceanographic Institution

    Do explosive volcanic eruptions on the seafloor of the Arctic Ocean contribute to the melting of the Arctic ice cap?
    No, not at all. The Arctic Ocean is a huge reservoir of water that can readily absorb and disperse the heat and volatile gases from the volcanic eruptions at the seafloor.

    To get a sense of how readily and easily the ocean disperses heat from the Earth’s crust, look at underwater volcanoes and hydrothermal vents in other regions of the ocean. At hydrothermal vents, scientists have found mineral-rich fluids with temperatures approaching 400°C (750°F) spewing out of the Earth. But if you measure temperatures just a few meters above or to the side of a vent, water temperatures return to just 2° to 3°C (35° to 37°F). And if you are floating on the ocean surface and a deep-sea volcano or vent erupts thousands of meters below, you wouldn’t detect a change in ocean temperatures.

    The water in the Arctic Ocean is stratified—layered like a cake—with lighter layers lying atop denser layers of water, like oil atop water. (Colder and/or saltier seawater is denser than warmer and/or less salty seawater.) Waters in the Arctic depths remain trapped near the bottom. They do not mix much with surface waters. Almost no heat is transmitted all the way up to the underside of the ice.

    During many Arctic expeditions, scientists have studied the movement of water, heat, and chemicals in the depths of the Arctic Ocean . They have found that heat and other emissions from the Arctic seafloor do not rise much higher than 500 to 1000 meters up from the ocean bottom. The volcanoes under the Arctic sea ice are 3,000 to 4,000 meters (approximately 2.5 miles) below
     
  9. Old Rocks
    Online

    Old Rocks Diamond Member

    Joined:
    Oct 31, 2008
    Messages:
    46,466
    Thanks Received:
    5,414
    Trophy Points:
    1,840
    Location:
    Portland, Ore.
    Ratings:
    +10,310
    Same article

    While the Arctic warming of the recent decades may have multiple causes, longer temperature reconstructions from paleoclimatic data (tree rings, ice cores, temperature records) indicate that the Arctic was warmer during the 20th century than at any time since 1600 (Overpeck et al., 1997). This reconstruction is weighted toward the summer season, and it does also show a variety of decadal-scale swings, including a cooling of the Arctic from the 1940s to the 1960s. The reconstruction suggests that natural variations occur on the decade-to-century timescale, and it implies that such variations may have combined with greenhouse-gas changes during the past century "to drive unprecedented changes in the Arctic environment" (Overpeck et al., 1997, p. 1255).

    The recent decades have also seen a shift of precipitation in the Arctic. The atmospheric circulation pattern that contributed to much of the post-1960 Arctic warming has also increased precipitation over subarctic Europe and the eastern North Atlantic (Dickson et al., 2000), and it has increased storminess in the Arctic. Recent assessments of 20th-century precipitation (IPCC, 1996) show that precipitation has increased by a greater percentage in the Arctic (65°N–85°N) than in any other latitudinal zone on the globe. Thus the Arctic has become a generally wetter as well as a warmer place over the past few decades, suggesting an acceleration of the hydrologic cycle in the Arctic. These changes have implications for soil moisture, vegetation, and river discharge. There are indeed indications that the seasonal "spike" in river discharge is occurring earlier in the spring in many Arctic rivers (Lammers et al., 2000).
     
  10. Old Rocks
    Online

    Old Rocks Diamond Member

    Joined:
    Oct 31, 2008
    Messages:
    46,466
    Thanks Received:
    5,414
    Trophy Points:
    1,840
    Location:
    Portland, Ore.
    Ratings:
    +10,310
    Quite serious. If it were only the Arctic, it would just be an interesting, albeit dangerous, anomouly. Not only the Arctic Polar Ice, but the Greenland Ice Cap, the Anarctic Ice cap, and virtually all the alpine glaciers are also losing ice. In other words, the warming is worldwide.
     

Share This Page