A very interesting update on what is going on in the science side of Climate Change.
1999 – Mann could not back up his idea to the public by showing the science of how he arrived at his numbers.
2001 – IPCC’s 3rd assessment report followed Mann’s ideas along with Allen and Tett (A&T) paper about modeling.
The paper’s main idea was empowered by following “Optimal Fingerprinting”.
Point being - For every action there is a reaction. So, how do we measure the Climate Change? Well, we created a bunch of models. Create the base data sets that could be used by the model’s runs. Then set the parameters on using the models. If three model’s results come close to each other then that is said to be correct.
Reality, we cannot prove Climate Change by measuring the Climate Change yet today. We know it is there and it exists, but it cannot be differentiated by measurement from Global Warming.
Instead, we use “Optimal Fingerprinting”. A little history, K. Hasselmann’s paper on “Optimal Fingerprints for the Detection of Time-dependent Climate Change” 1993 https://journals.ametsoc.org/view/journals/clim/6/10/1520-0442_1993_006_1957_offtdo_2_0_co_2.xml set the foundation for detection of Climate Change.
2006 - Al Gore used Mann’s Hockey Stick with questionable peer reviews and Climate Change became a political issue.
2021 – Fast forward to 2021. The IPCC just published a report showing their “Optimal Fingerprinting” methodology. IPCC was using A&T’s 1999 report as stated above in 2001. “Checking for model consistency in optimal fingerprinting” A&T.
McKitrick published a report***,” The IPCC’s attribution methodology is fundamentally flawed”.*** Checking for model consistency in optimal fingerprinting: a comment - Climate Dynamics
Point being. Garage in, garage out. A&T’s method has not been checked for errors and deficiencies in the processes when used by scientists. Hundreds of studies over the past two decades have used it for analyzing climate data. McKitrick is asking the science community to show him wrong in his claim that methodology on which they have long relied for attributing climate change to greenhouse gases is seriously flawed and its results are unreliable and largely meaningless.
McKitrick is putting his data and reputation on the line. It most likely will not change the political Climate Change but the scientific Climate Change could be drastically altered.