Page 2 of 6 FirstFirst 1234 ... LastLast
Results 11 to 20 of 60

Thread: Hurricanes and climate change

  1. #11
    tWebber TheLurch's Avatar
    Join Date
    Jan 2014
    Location
    Northeast USA
    Faith
    MYOB
    Gender
    Male
    Posts
    858
    Amen (Given)
    57
    Amen (Received)
    246
    Quote Originally Posted by seer View Post
    Nature? Where I sit in New England it was once covered in 50 foot glaciers, the Arctic was once tropical.
    Right, but nature isn't magic. It cycles through physical mechanisms. Like the ENSO cycle, which we know is caused by the flow of surface ocean waters in the western pacific. So what's the physics of the natural cycle that you think is happening?

  2. #12
    tWebber seer's Avatar
    Join Date
    Jan 2014
    Location
    New England
    Faith
    Christian
    Gender
    Male
    Posts
    16,419
    Amen (Given)
    729
    Amen (Received)
    3330
    Quote Originally Posted by TheLurch View Post
    Right, but nature isn't magic. It cycles through physical mechanisms. Like the ENSO cycle, which we know is caused by the flow of surface ocean waters in the western pacific. So what's the physics of the natural cycle that you think is happening?
    Did you read my quote? Obviously we have had greater fluctuations, greater rise in heat, in less time, that what we see today. And we really don't know why. And if we don't know those mechanisms how do we know they are not happening today, or something similar. It is clear that nature can do it on her own, whether we know how that happens or not.

    Earth's Climate During the Last Ice Age

    Unlike the relatively stable climate Earth has experienced over the last 10,000 years, Earth's climate system underwent a series of abrupt oscillations and reorganizations during the last ice age between 18,000 and 80,000 years ago (Dansgaard 1984, Bond et al. 1997, 1999). These climate fluctuations were first discovered when scientists reconstructed past temperature variability over Greenland by analyzing tiny changes in the relative abundance of the oxygen-16 isotope versus the oxygen-18 isotope (noted as δ18O and reported in parts per thousand) in ice cores recovered from Greenland glaciers. Each successively deeper ice layer represents a snapshot of Earth's climate history from the past, and together, the oxygen isotope record told a story of abrupt, millennial-scale climate shifts in air temperatures over Greenland between extremely cold stadial conditions and relatively mild interstadial periods during the last ice age (Figure 1) (Alley 2000, Alley et al. 2003). There are twenty-five of these distinct warming-cooling oscillations (Dansgaard 1984) which are now commonly referred to as Dansgaard-Oeschger cycles, or D-O cycles. One of the most surprising findings was that the shifts from cold stadials to the warm interstadial intervals occurred in a matter of decades, with air temperatures over Greenland rapidly warming 8 to 15C (Huber et al. 2006). Furthermore, the cooling occurred much more gradually, giving these events a saw-tooth shape in climate records from most of the Northern Hemisphere

    Although the D-O climate cycles have now been found in many other climate proxy records around the globe (Voelker 2002), the reason why Earth's climate was so much more variable during the last ice age is still unknown. Some theories suggest that changes in ocean circulation due to natural variations of North Atlantic surface water salinity were the trigger for the D-O events (the salt oscillator hypothesis) (Birchfield & Broecker 1990, Broecker et al. 1990a, Zaucker & Broecker 1992), while others argue changes in atmospheric circulation were the driver (the wind field oscillation hypothesis)

    https://www.nature.com/scitable/know...t-ice-24288097
    "Heaven offers nothing that the mercenary soul can desire. It is safe to tell the pure in heart that they shall see God, for only the pure in heart want to. There are rewards that do not sully motives. A man's love for a woman is not mercenary because he wants to marry her, nor his love for poetry mercenary because he wants to read it, nor his love of exercise less disinterested because he wants to run and leap and walk. Love, by definition, seeks to enjoy its object. C.S. Lewis

  3. #13
    Troll Magnet Sparko's Avatar
    Join Date
    Jan 2014
    Faith
    Christian
    Gender
    Male
    Posts
    30,538
    Amen (Given)
    2570
    Amen (Received)
    15139
    Quote Originally Posted by TheLurch View Post
    Regarding the hurricanes that happen to hit the US - what matters from the climate perspective is hurricanes total. The climate doesn't respect human-drawn nation borders.
    Do you have any evidence of any different statistics regarding the global statistics? Why would the US be spared an increase in hurricanes but not the rest of the world?

    What evidence do you base that on? And what's doing the cycling?
    Evidence of climate change over the last several million years. It appears to just be natural: Ice ages interspersed with warm periods. There are also sun spot cycles and the like for shorter term periods.

  4. #14
    tWebber HMS_Beagle's Avatar
    Join Date
    Jan 2014
    Faith
    Thinking
    Gender
    Male
    Posts
    1,933
    Amen (Given)
    37
    Amen (Received)
    361
    Quote Originally Posted by seer View Post
    Did you read my quote? Obviously we have had greater fluctuations, greater rise in heat, in less time, that what we see today. And we really don't know why. And if we don't know those mechanisms how do we know they are not happening today, or something similar. It is clear that nature can do it on her own, whether we know how that happens or not.
    Did you bother to read the paper you linked to? The authors are describing LOCAL oscillations and fluctuations in climate in specific areas, not overall GLOBAL events or temperature averages.

  5. #15
    Troll Magnet Sparko's Avatar
    Join Date
    Jan 2014
    Faith
    Christian
    Gender
    Male
    Posts
    30,538
    Amen (Given)
    2570
    Amen (Received)
    15139
    Quote Originally Posted by TheLurch View Post
    Right, but nature isn't magic. It cycles through physical mechanisms. Like the ENSO cycle, which we know is caused by the flow of surface ocean waters in the western pacific. So what's the physics of the natural cycle that you think is happening?
    I have read it is due to "wobbling" of the earth in it's orbit. such as Milankovitch cycles.

  6. #16
    tWebber seer's Avatar
    Join Date
    Jan 2014
    Location
    New England
    Faith
    Christian
    Gender
    Male
    Posts
    16,419
    Amen (Given)
    729
    Amen (Received)
    3330
    Quote Originally Posted by HMS_Beagle View Post
    Did you bother to read the paper you linked to? The authors are describing LOCAL oscillations and fluctuations in climate in specific areas, not overall GLOBAL events or temperature averages.
    They are speaking globally:

    Unlike the relatively stable climate Earth has experienced over the last 10,000 years, Earth's climate system underwent a series of abrupt oscillations and reorganizations during the last ice age between 18,000 and 80,000 years ago.

    Although the D-O climate cycles have now been found in many other climate proxy records around the globe (Voelker 2002), the reason why Earth's climate was so much more variable during the last ice age is still unknown.
    "Heaven offers nothing that the mercenary soul can desire. It is safe to tell the pure in heart that they shall see God, for only the pure in heart want to. There are rewards that do not sully motives. A man's love for a woman is not mercenary because he wants to marry her, nor his love for poetry mercenary because he wants to read it, nor his love of exercise less disinterested because he wants to run and leap and walk. Love, by definition, seeks to enjoy its object. C.S. Lewis

  7. #17
    tWebber HMS_Beagle's Avatar
    Join Date
    Jan 2014
    Faith
    Thinking
    Gender
    Male
    Posts
    1,933
    Amen (Given)
    37
    Amen (Received)
    361
    Quote Originally Posted by seer View Post
    They are speaking globally:
    OK, you didn't read the paper and have no idea what the paper is discussing.

  8. #18
    tWebber TheLurch's Avatar
    Join Date
    Jan 2014
    Location
    Northeast USA
    Faith
    MYOB
    Gender
    Male
    Posts
    858
    Amen (Given)
    57
    Amen (Received)
    246
    Quote Originally Posted by seer View Post
    Did you read my quote? Obviously we have had greater fluctuations, greater rise in heat, in less time, that what we see today. And we really don't know why.
    Why says we don't know why?

    Edited to add: Sparko, just above, points out that we do know what drives some of the cycles.
    Last edited by TheLurch; 09-12-2017 at 06:09 PM.

  9. #19
    tWebber TheLurch's Avatar
    Join Date
    Jan 2014
    Location
    Northeast USA
    Faith
    MYOB
    Gender
    Male
    Posts
    858
    Amen (Given)
    57
    Amen (Received)
    246
    Quote Originally Posted by Sparko View Post
    Do you have any evidence of any different statistics regarding the global statistics? Why would the US be spared an increase in hurricanes but not the rest of the world?
    Sure.
    http://www.ssec.wisc.edu/~kossin/art...2013_JClim.pdf
    http://onlinelibrary.wiley.com/doi/1...6GL025881/full

    Again, total number of storms isn't changing much, but intensity's going up. Second link is a 20 year study, which is a bit short to show climactic trends, but does show a regional difference, which is what you're getting at.

    Quote Originally Posted by Sparko View Post
    Evidence of climate change over the last several million years. It appears to just be natural: Ice ages interspersed with warm periods. There are also sun spot cycles and the like for shorter term periods.
    As you say in your later post, orbital cycles drive glacial cycling. But we understand how these orbital cycles work, and we know that their peak warming for this interglacial period was over 5,000 years ago. And, in fact, it appears that the global temperature has been dropping since then until their recent reversal.
    http://www.realclimate.org/images//Marcott.png
    (I can dig up the original Marcotte paper if you want to see it.)

    Solar activity's been going down since a peak around the 1960s or so, and yet temperatures have gone up.
    https://static.skepticalscience.com/pics/TvsTSI.png

    So what's driving the cycle?

  10. #20
    tWebber seer's Avatar
    Join Date
    Jan 2014
    Location
    New England
    Faith
    Christian
    Gender
    Male
    Posts
    16,419
    Amen (Given)
    729
    Amen (Received)
    3330
    Quote Originally Posted by TheLurch View Post
    Why says we don't know why?
    The paper I linked: Although the D-O climate cycles have now been found in many other climate proxy records around the globe (Voelker 2002), the reason why Earth's climate was so much more variable during the last ice age is still unknown.

    They had a much more rapid and greater warming than what we see today, yet we do not know why.
    "Heaven offers nothing that the mercenary soul can desire. It is safe to tell the pure in heart that they shall see God, for only the pure in heart want to. There are rewards that do not sully motives. A man's love for a woman is not mercenary because he wants to marry her, nor his love for poetry mercenary because he wants to read it, nor his love of exercise less disinterested because he wants to run and leap and walk. Love, by definition, seeks to enjoy its object. C.S. Lewis

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •