Interesting that Kevin Trenberth a founding member of the AGW...

  1. 9,012 Posts.
    Interesting that Kevin Trenberth a founding member of the AGW scam,  ead author in the IPCC reports made this comments back in 2007 about Climate Models

    I come across this tonight on another site that referenced back to this link

    How is it that science is settled with the data of the day and then a leading author acknowledges that models are not initialised nor do they resemble current climate.  wtf idiots are we dealing with that still swallow the BS.


    http://blogs.nature.com/climatefeedback/2007/06/predictions_of_climate.html

    Even if there were, the projections are based on model results that provide differences of the future climate relative to that today. None of the models used by IPCC are initialized to the observed state and none of the climate states in the models correspond even remotely to the current observed climate. In particular, the state of the oceans, sea ice, and soil moisture has no relationship to the observed state at any recent time in any of the IPCC models.  There is neither an El Niño sequence nor any Pacific Decadal Oscillation that replicates the recent past;  yet these are critical modes of variability that affect Pacific rim countries and beyond.  The Atlantic Multidecadal Oscillation, that may depend on the thermohaline circulation and thus ocean currents in the Atlantic, is not set up to match today’s state, but it is a critical component of the Atlantic hurricanes and it undoubtedly affects forecasts for the next decade from Brazil to Europe. Moreover, the starting climate state in several of the models may depart significantly from the real climate owing to model errors.  I postulate that regional climate change is impossible to deal with properly unless the models are initialized.

    The current projection method works to the extent it does because it utilizes differences from one time to another and the main model bias and systematic errors are thereby subtracted out. This assumes linearity. It works for global forced variations, but it can not work for many aspects of climate, especially those related to the water cycle. For instance, if the current state is one of drought then it is unlikely to get drier, but unrealistic model states and model biases can easily violate such constraints and project drier conditions. Of course one can initialize a climate model, but a biased model will immediately drift back to the model climate and the predicted trends will then be wrong. Therefore the problem of overcoming this shortcoming, and facing up to initializing climate models means not only obtaining sufficient reliable observations of all aspects of the climate system, but also overcoming model biases. So this is a major challenge.
 
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