Climate Change 2013 The Physical Science Basis

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1. ideonexusMar 2017
   We already have a well-established method for challenging climate research. It's called the "Climate Change 2013: The Physical Science Basis" report [1]. It comprises 1,500 pages, surveying the results from thousands of journal articles, and is written by 259 experts from fields including meteorology, physics, oceanography, statistics, engineering, ecology, social sciences and economics. The IPCC regularly updates and republishes this report to include more recent findings and data.

   Anyone who has bothered to download and even skim this report knows how exhaustive, thorough, and--most of all--conservative it is in its predictions and findings. It dedicates a significant amount of space to pointing out where its predictions have failed and where the data does not support the theory of global warming.

   Anyone who wants to "challenge" climate research by completely circumventing the existing dialogue that has been taking place in peer-reviewed journals for decades now to take their case directly to the policy-makers is a charlatan.

   [1] https://www.ipcc.ch/report/ar5/wg1/

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2. todd8Aug 2016
   From the IPCC's Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assess- ment Report of the Intergovernmental Panel on Climate Change, Chapter 9 Evaluation of Climate Models, pp. 749-750.

   > With very few exceptions (Mauritsen et al., 2012; Hourdin et al., 2013) modelling centres do not routinely describe in detail how they tune their models. Therefore the complete list of observational constraints toward which a particular model is tuned is generally not available.

   From the House of Commons Science and Technology report The disclosure of climate data from the Climatic Research Unit at the University of East Anglia paragraph 54:

   > 54. It is not standard practice in climate science and many other fields to publish the raw data and the computer code in academic papers. We think that this is problematic because climate science is a matter of global importance and of public interest, and therefore the quality and transparency of the science should be irreproachable. We therefore consider that climate scientists should take steps to make available all the data used to generate their published work, including raw data; and it should also be made clear and referenced where data has been used but, because of commercial or national security reasons is not available. Scientists are also, under Freedom of Information laws and under the rules of normal scientific conduct, entitled to withhold data which is due to be published under the peer-review process.78 In addition, scientists should take steps to make available in full their methodological workings, including the computer codes. Data and methodological workings should be provided via the internet. There should be enough information published to allow verification.

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3. sanxiynSep 2015
   From IPCC report "Climate Change 2013: The Physical Science Basis" chapter 2:

   "In summary, there continues to be a lack of evidence and thus low confidence regarding the sign of trend in the magnitude and/or frequency of floods on a global scale." (2.6.2.2)

   "In summary, the current assessment concludes that there is not enough evidence at present to suggest more than low confidence in a global-scale observed trend in drought since the middle of the 20th century, owing to geographical inconsistencies in the trends." (2.6.2.3)

   It's not as simple as more energy -> more chaotic weather -> more severe floods and droughts. Unlike other parts of global warming, many changes in extereme events are hypothetical and unsettled. (For floods, we are not sure of sign!)

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4. acqqJan 2014
   The climate research is not the weather forecasting. I wanted to give you an idea how litle sense has to predict for any particular year. The Earth doesn't function that way. The trend however is absolutely predictable.

   For the future, look here (the Figure SPM.10 from the last IPCC report, PDF linked later):

   http://www.easterbrook.ca/steve/2013/10/what-does-the-new-ip...

   What will happen depends only on our fossil fuel consumption. The last IPCC reports does predictions for different "Representative Concentration Pathways": Simulations were performed with prescribed CO2 concentrations reaching 421 ppm (RCP2.6), 538 ppm (RCP4.5), 670 ppm (RCP6.0), and 936 ppm (RCP 8.5) by the year 2100.

   It you know we're already over 400 ppm, drop the RCP2.6 (dark blue) curve, since to achieve it we have to soon stop consuming fossil fuels (Figure 12.46).

   By 2100 it will be between 1.5 and 4 degrees warmer than now, depending on how much we're ready to cut our fossil fuels use. And that is immense increase. We already observe significant differences between now and hundred years ago everywhere, which was only 0.85 deg C difference!

   The "short" report (PDF) is:

   http://www.climatechange2013.org/images/uploads/WGI_AR5_SPM_...

   The full report is huge so I link the top page:

   http://www.ipcc.ch/report/ar5/wg1/

   "Climate Change 2013: The Physical Science Basis"

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