Register to Comment
Page 3340 of 6600 FirstFirst ... 234028403240329033303338333933403341334233503390344038404340 ... LastLast
Results 33,391 to 33,400 of 65999
Like Tree13963Likes
  1. #33391
    realist realist is offline

    Join Date
    May 2006
    Posts
    2,621

    Quote Originally Posted by owedtojoy View Post
    Further, the bottom charts are charts of temperature trends per 9 year intervals, not of temperature itself. While there is a recent dimunition in decadal trends, the trend of the trends since 1960 seem to be rising to me.
    If you look at the top chart, the trend since 1980 seems to be falling.


    A little more than a year after we had published our millennial hockey stick reconstruction, paleoclimatologist Thomas Crowley of Texas A&M University (and coauthor of the Crowley and Lowery reconstruction discussed earlier) published findings based on the use of a theoretical climate model simulation designed to investigate causes of past temperature change. Crowley subjected the model to estimated changes in natural factors over the past thousand years, using indirect measures of changes in solar output and explosive volcanic activity, information on both of which can be recovered from atmospheric deposits in polar ice cores.

    These simulations revealed that the natural factors could explain the extent of medieval warmth in our reconstruction; in the model, this warmth arose from a relative lack of cooling volcanic eruptions combined with relatively high levels of solar output. The natural factors could also explain the cooler conditions of the ensuing Little Ice Age, which resulted from relatively low levels of solar output and more frequent explosive volcanic eruptions.

    Fed the natural factors only, the model could not, however, reproduce the abrupt twentieth century warming. In fact, the model predicted that the climate should have cooled in recent decades, rather than warmed, if only natural factors had been at play.
    It was only when Crowley added the modern human influences – increasing greenhouse gas concentrations primarily from fossil fuel burning and the regional cooling effect of industrial sulphate aerosols emissions – to the model simulation, that it was able to track the hockey stick all the way through to the present.

    The conclusion was clear: Natural factors could explain the temperature changes of the past millennium through the dawn of the industrial revolution, but only human influences could explain the unusual recent warming.
    Michael Mann on climate wars: 'the hockey stick did not suddenly appear out of left field' | Environment | theguardian.com

    I have not seen the study by Crowley but it sounds like his results are more in keeping with what has been happening in recent decades.
    Sign in or Register Now to reply

  2. #33392
    owedtojoy owedtojoy is online now
    owedtojoy's Avatar
    Join Date
    Feb 2010
    Posts
    39,637

    Quote Originally Posted by realist View Post
    If you look at the top chart, the trend since 1980 seems to be falling.



    .
    Yes, but the trend also fell in the 1960s, 1980s and 1990s, so if the trend is falling now, it will pick up again - as the physics says.

    I have always maintained there is no "pause" in global warming, just a temporary dimunition in surface temperature trend. The chart lends further credibility to that.

    Let's not cherry-pick endpoints. Here is my own chart of surface temperature trends, these are moving averages of 17-year and 30-year trends, weighted by their variance (high variance, low weight).


    My chart is in degrees C/ yr, the Met Office in degrees C/ decade. Since my trends are over longer times, my chart is less noisy. But both show a peaking in 2005 or so, and a diminution since. Not a stop in warming, just warming at a lower rate.
    Last edited by owedtojoy; 24th December 2014 at 08:21 AM.
    Sign in or Register Now to reply

  3. #33393
    owedtojoy owedtojoy is online now
    owedtojoy's Avatar
    Join Date
    Feb 2010
    Posts
    39,637

    Quote Originally Posted by realist View Post

    Michael Mann on climate wars: 'the hockey stick did not suddenly appear out of left field' | Environment | theguardian.com

    I have not seen the study by Crowley but it sounds like his results are more in keeping with what has been happening in recent decades.
    You would be ill advised to compare a reconstruction of over thousand years of temperature from proxies, to less than a decade with accurate thermometers.

    Reconstructions from proxies just do not have the resolution of decades - more like centuries.

    This is the study referred to:


    Mann study in red, Crowley-Lowery in blue.

    NOAA Paleoclimatology Program - Crowley 2000 Causes of Climate Change Over the Past 1000 Years
    Last edited by owedtojoy; 24th December 2014 at 08:25 AM.
    Sign in or Register Now to reply

  4. #33394
    owedtojoy owedtojoy is online now
    owedtojoy's Avatar
    Join Date
    Feb 2010
    Posts
    39,637

    Comment on Typhoon Haiyan


    A proposal is afoot to add a category 6 storm to the scale.

    Should There be a Category 6 for Hurricanes? – Greg Laden's Blog
    Sign in or Register Now to reply

  5. #33395
    owedtojoy owedtojoy is online now
    owedtojoy's Avatar
    Join Date
    Feb 2010
    Posts
    39,637

    Haiyan is an example of the type of extreme storm that may become more frequent as the climate continues to warm

    ... But there is more consensus about the stormier future than there is about the present.

    The researchers also urged caution in attributing Haiyan’s strength to global warming, given the lack of evidence that manmade global warming has had any detectable influence on Western Pacific typhoons, let alone tropical cyclones in general (an umbrella term that includes typhoons and hurricanes).



    Climate research has not yet provided a clear picture of how global warming is altering tropical cyclones around the world. Importantly, though, studies are providing clues that we may be in for a much stormier future, with more intense storms that bring with them stronger winds, heavier rainfall, and greater storm surge due to sea level rise.

    Less cyclone frequency, but more intense cyclones. This is a precursor.

    Super Typhoon Haiyan: A Hint of What's to Come? | Climate Central

    Projected changes in tropical cyclone statistics. All values represent expected percent change in the average over period 2081–2100 relative to 2000–2019, under a high emissions scenario. The metrics presented here include the total annual frequency of tropical storms, the annual frequency of Category 4 and 5 storms, the mean lifetime maximum intensity of tropical cyclones, and the precipitation rate within 200 km of the storm center at its most intense point. The solid blue line is the best guess of the expected percent change, and the coloured bar provides the likely confidence interval for this value.
    Sign in or Register Now to reply

  6. #33396
    Trainwreck Trainwreck is online now

    Join Date
    Sep 2012
    Posts
    21,092

    Quote Originally Posted by owedtojoy View Post

    A proposal is afoot to add a category 6 storm to the scale.

    Should There be a Category 6 for Hurricanes? – Greg Laden's Blog
    Haiyan was cat 4
    Sign in or Register Now to reply

  7. #33397
    Agnotologist Agnotologist is offline

    Join Date
    Jun 2010
    Posts
    4,925

    Quote Originally Posted by realist View Post
    But what you are ignoring is the fact that intermittent renewables provide, according to James Hansen, only 1-1.5% of total energy. That means at least 98.5% of energy is provided by other sources and therefore the pro rata monetary amount paid in subsidies would be much higher. Here is a summary of the cost of solar generated power in Germany as compared to equivalent nuclear power:


    The Breakthrough Institute - Doing the Math: Comparing Germany’s Solar Industry to Japan’s Fukushima Reactors

    And Hansen also disagrees with you when he says that, after nuclear, fossil fuels are currently the cheapest form of energy. As one of the foremost opponents of fossil fuels in the world, I am pretty sure he would not say that if it were not true.


    - See more at: The Australian

    Hansen is not alone in his view as the letter referred to in this article explains:


    Experts say nuclear power needed to slow warming - SFGate

    I have always been very anti nuclear but the new technologies currently being discussed sound a little more encouraging as to their safety and viability to be considered as a reliable fuel source for the future.
    Unfortunately your sources are not unbiased. Comparing a nscent industry with an established industry is "apples and oranges," or coal and gold. The subsidies to renewables are higher in some skewed ratio that ignores all subsequent experience. They are lowering rapidly for renewables while they are still heavy for fossil fuels.

    Wind Power is now cheaper than even coal, as the German experience shows. Comparing coal in established plants with startups for wind is duplicitous. However, coal is going the way of the Dodo regardless of the raw cost of production for reasons that should jnot need to be discussed any longer.

    Oil is the elephant now. The total subsidies are enormous and, when externalities rae taken in, they have been estimated to be as high as two trillion dollars worldwide.

    Comparing the price of solar that is still largely experimental is - choose your word. Solar is now only about one fifth of what it was hust a decade ago and dropping further rapodly as new technologies are coming down the pipe at speed. The failures of some solar companies have come about because they are locked into technology for the present production while newer and vastly cheaper technologies have overtaken them.

    Again, nuclear. New nuclear is a distant and costly prospect although there is some belief that a new generation of that will be cheaper and safer. Thorium might help - might.

    Not fifteen miles from me, a nuclear plant is being refurbished but the plan to build two new reactors there has been scrapped. They will not be needed. In part because conservation has made some dent; in part because renewables are making inroads; in part because of the cost.

    I would not take a report in the "Australian" as a faithful representation of Hansen. It has rarely been faithful to any aspect of climate change. I doubt it is now.
    Sign in or Register Now to reply

  8. #33398
    Agnotologist Agnotologist is offline

    Join Date
    Jun 2010
    Posts
    4,925

    It does not surprise me, btw, that Hansen now wants nuclear to be encouraged. The developed world has "dragged its feet" so long on developing renewables that desperate measures are needed.

    Disposing of waste, something that has nowhere been resolved as yet, will have to be a problem for the future. Less of a problem than Global warming bot one that may never be satisfactorily solved.
    Sign in or Register Now to reply

  9. #33399
    Agnotologist Agnotologist is offline

    Join Date
    Jun 2010
    Posts
    4,925

    Quote Originally Posted by Trainwreck View Post
    Haiyan was cat 4
    It was a category 5 before it was a category 4. Notably, like Sandy, it carried more water than a Cat 4 would have done in the past and did more damage because of it.

    Also, it was the third cat 5 to hit the Philippines in the past few years.

    The tropical cyclones are, as predicted, becoming stronger and more damaging.
    Sign in or Register Now to reply

  10. #33400
    realist realist is offline

    Join Date
    May 2006
    Posts
    2,621

    Quote Originally Posted by Agnotologist View Post
    I would not take a report in the "Australian" as a faithful representation of Hansen. It has rarely been faithful to any aspect of climate change. I doubt it is now.
    Sign in or Register Now to reply

Sign in to CommentRegister to Comment