Then compare the result for each case with the PDF derived from the 5 (or whatever)
historical model runs, and use the result to generate a weighting for the model's simulations.
Fig. 1 Violinplots of monthly surface temperature results for 9 GISS ER
historical model runs (1880 - 2003), their average (orange), and the HadCRUT3 global surface temperature dataset (red).
[CAPTION: Fig. 1 Violinplots of monthly surface temperature results for 9 GISS ER
historical model runs (1880 - 2003), their average (orange), and the HadCRUT3 global surface temperature dataset (red).
Not exact matches
The problem is when investors adopt theories and
models that embed the most optimistic assumptions possible,
run contrary to
historical evidence, or embed subtle peculiarities that actually drive the results (see, for example, the «novel valuation measures» section of The Diva is Already Singing).
For assessing the global ocean - carbon sink, McKinley and her co-authors from the National Oceanic and Atmospheric Administration (NOAA) Pacific Marine Environmental Laboratory, NCAR and the University of Colorado Boulder used the
model to establish a long -
running climate scenario from
historical data.
Nicole Sharp, an aerospace engineer who
runs a Tumblr blog on fluid dynamics, and Jordan Kennedy at Harvard University gathered data from
historical records and
ran experiments on how molasses flows under various conditions, then fed it all into computer
models.
The first issue is that calculating TCR for each
model from
historical «All forcing»
runs (histAll) requires using the same simulations and time periods as used in calculating the forcings.
This
model looks at the
historical data of a climate variable (e.g., temperature) and has a best - fit line
running through these data.
Ideally, one would want to do a study across all these constraints with
models that were capable of
running all the important experiments — the LGM,
historical period, 1 % increasing CO2 (to get the TCR), and 2xCO2 (for the
model ECS)-- and build a multiply constrained estimate taking into account internal variability, forcing uncertainties, and
model scope.
We got the official
run - down of the new Widowmaker at this year's Goodwood Festival of Speed, and to celebrate the launch of the new range - topping neunelfer, Porsche rolled out some
historical GT2 and GT2-esque
models.
The ad, which names this as a «fried laforza» from the «peanut Farina» factory, does not list the
model year or
running condition, but given the
historical penchant for the LaForza to remain temperamental at best, we're guessing a trailer is probably needed.
The tools also allow you to
run Monte Carlo simulations, find
historical efficient frontiers, and test quantitative and factor based investing
models.
When I quizzed Thorsten about this a couple of years ago he told me that they hadn't done a
historical run (let alone an LGM) with the
model and that he didn't think it would be any good.
Ideally, one would want to do a study across all these constraints with
models that were capable of
running all the important experiments — the LGM,
historical period, 1 % increasing CO2 (to get the TCR), and 2xCO2 (for the
model ECS)-- and build a multiply constrained estimate taking into account internal variability, forcing uncertainties, and
model scope.
As a check of this, one could comparing the climate
model simulations of temperature change using the
historical forcing
runs with the temperature change produced by the same
models under CO2 - only forcing
runs * at times of equivalent total forcing change *.
Then, for the next year, pick another random
historical year's weather,
run the
model forwards another year, and so on.
The GCM
model performance in warming in minimum temperatures through the long
historical runs is not good at all.
Nowadays, a common check is to see how the
models check with
historical records: ice core samples have given us enough data about the ice ages to be able to
run the
models in «ice age mode» — and they seem to agree very well with the data.
Training consisted of
running the
model repeatedly over several days using as input eight years of Albuquerque's
historical weather data taken from NREL's SOLMET database.
Thanks for the 3 papers, the 1st was a real eye openner but was essentially confirming what I said which is that most
model attribution expts based on comparison of
historical forcing and
runs held at pre - industrial condition suggest long term change is essentially forced.The point is the Karnauskas paper bucks the trend in understanding as expressed by the Ipcc (the consensus or whatever).
«Lewis in subsequent comments has claimed without evidence that land use was not properly included [viii] in our
historical runs, and that there must be an error [ix] in the
model radiative transfer.
It might be very useful to
run a computer
model simulation in which the ENSO is constrained to follow its known
historical behavior, so we can see how it might have affected actual history rather than a gereric «earth system.»
Tropical pacific surface waters easily warm just as much in
model -
runs that apply
historical external forcing values and let the simulated ENSO cycle do its random stuff.
The «HIST»
model runs use
historical data for climate forcing, to estimate the average temperature change (and other variables) simply due to climate forcing.
The
models were
run with
historical forcing up to 2000 and projected forcing after that.
I chose that because a) there are nine
runs available and b) the GISS
model is one of the more complex
models and c) it's one of the longest
historical runs (n = 1488 months).
This question is of interest to me because I just took a look at the GISS EH
model's
historical runs.
This section deals with the realistic case where
models have
run ensembles of
historical simulations of various sizes.
Both DECK and the CMIP6
Historical Simulation should be
run for each
model configuration used in the subsequent CMIP6 - Endorsed MIPs.
I would predict that the Aldrin method would not be able to accurately determine 2xCO2 ECS for CMIP5
models if tested against
historical runs rather than 1 % CO2 per year, and that it would tend towards significant underestimates.
This project
ran two climate
model experiments: one, «
Historical» included both human - caused greenhouse gas emissions and natural emissions, such as volcanoes; the second, «HistorialNat» included only the natural emissions, and deliberately left out human - caused emissions, to see how the climate might have changed without them.
These
models (I have more than 35 years experience
running these) ideally require a
historical record of long duration that is used for calibrating (fitting the data) for part of the record and then validating (checking the sim results with measured data) for the remaining part of the record.
I can appreciate that curve fitting doesn't really make sense when talking about
running climate
models initialised on
historical data and comparing the output to observations.
-LSB-...] in subsequent comments has claimed without evidence that land use was not properly included [viii] in our
historical runs, and that there must be an error [ix] in the
model radiative -LSB-...]
Remember that the scientists believe their
models and their assumptions about a strong CO2 effect, so they have
modeled the non-anthropogenic effect by
running their
models, tuning them to
historical actuals, and then backing out the anthropogenic forcings to see what is left.
To help address these challenges, scientists
run hurricane
models calibrated with observations over the
historical period to project future trends and understand the major factors driving these trends.
Models which don't make big excursions (can) win (given any overfit to the
historical record) because they don't bounce around so unpredictably on every damned
run, so they can fit the
historical record more closely.
Recommendations for verification are: 1) comparison to other
models 2) degenerate tests 3) event validity 4) extreme event validity 5) extreme condition tests 6) «face» validity tests 7) fixed value tests 8)
historical data validation 9) internal validity (stochastic
runs) 10) multistage validation 11) parameter variability - sensitivity analysis 12) predictive validation 13) traces 14) turing tests (i didn't know what this is so googled ECWMF turing test, and i got 150 hits)