Sentences with phrase «using calibration data»

Using calibration data.

Not exact matches

Google has also incorporated some of the reinforcement learning techniques used by DeepMind in its data centers to discover the best calibrations that result in lower power consumption.

The latest study uses a new calibration of data taken from NASA's Moon Mineralogy Mapper, which flew aboard India's Chandrayaan - 1 spacecraft, to quantify how much water is present on a global scale.

The team used that calibration data to detect the signature of vinyl cyanide at specific wavelengths of light and calculate its abundance.

Using different calibration and filtering processes, the two researchers succeeded in combining a wide variety of available data from temperature measurements and climate archives in such a way that they were able to compare the reconstructed sea surface temperature variations at different locations around the globe on different time scales over a period of 7,000 years.

From spectroscopic data, researchers calculate calibration equations that allow them to estimate the properties of corks faster than using the traditional methods.

The LUX team used this new calibration to double - check the data from the detector's first run.

We are using the first 43 days of science data to characterize these effects and to develop detection and mitigation methods that will be implemented in the calibration pipeline.

(The description of our factor construction methodology is available in Appendix B.) We use the first 24 years of data (Jan 1967 — Dec 1990) in the initial model calibration, encompassing several valuation cycles, and use the remaining data (Jan 1991 — Oct 2011) to run the model comparison.

[Response: The satellite altimeter data point is shown in our Vermeer & Rahmstorf 2009 paper as an independent validation point that was not used for calibration, and it fits the relationship perfectly.

They then did a comparison and calibration using an independent satellite data set.

Despite the difficulties of calibration that makes an absolute radiative imbalance measurement impossible — the anomalies data contains essential information on climate variability that can be used to understand and close out the global energy budget — changes in which are largely OHC.

However, the reason why the PC summaries are used in the first place in paleo - reconstructions is that using the full proxy set often runs into the danger of «overfitting» during the calibration period (the time period when the proxy data are trained to match the instrumental record).

This does two things that may be important: it allows the non-annually resolved proxies to be used (recent previous reconstructions, e.g. MBH98, Esper et al., used only those with at least a value each year, to allow calibration against the instrumental record; Moberg's approach allows the use of data that only provide 50 y means); and it throws away the long - term signal from the tree rings, which they consider to be untrustworthy.

In such cases, validation experiments are done (and described in detail in the paper), wherein one part of the record (e.g. the earlier part) is used to calibrate the proxy data, and a reconstruction is independently performed over the other part of the record (e.g. the late part), where it can be directly compared against the part of the instrumental record not used in the calibration process.

Nichol: we don't use satellite data in our calibration.

In the case of the North American ITRDB data used by MBH98, the reference means were chosen to be the 20th century calibration period climatological means.

[Response: Following up Gavin's comment, it has indeed already been shown — based on experiments with synthetic proxy data derived from a long climate model simulation (see Figure 5 herein)-- that the calibration method used by Moberg et al is prone to artificially inflating low - frequency variability.

Networks of tree ring width and tree ring density chronologies are used to infer past temperature changes based on calibration with temporally overlapping instrumental data.

Although each of the temperature reconstructions are different (due to differing calibration methods and data used), they all show some similar patterns of temperature change over the last several centuries.

2) Even if the satellite data contradicted the remainder of the data, is it more likely that one data set depending on the calibration of one instrument is correct, or dozens of data sets using dozens of methods all showing the same pattern of warming?

«The principal difficulty is that the divergence disallows the direct calibration of tree growth indices with instrumental temperature data over recent decades (the period of greatest warmth over the last 150 years), impeding the use of such data in climatic reconstructions.»

We used methods that carefully consider potential sources of uncertainty in the data, including uncertainty in proxy calibration and in dating of the samples»

Thus it «s better that very many different thermometers are used by many different people following different practices than that a few ships using one thermometer each make the measurements using procedures that vary only slowly, unless accurate data is available on the calibration of those few thermometers and the procedures used.

Following MM05a, the first PCs of this process were then used as regressors in a calibration with the Northern Hemisphere mean from the MBH verification data grid and the RE of verification determined, for each Monte Carlo iteration.

The RegEm algorithm of [Tapio Schneider] was used to estimate missing values for proxy series terminating before the 1995 calibration internval endpoint, based on their mutual covariance with the other available proxy data over the full 1850 - 1995 calibration interval.

This adiabatic model was verified, with a precision of 0.1 %, by comparing the results obtained for the temperature distribution in the troposphere of the Earth with the standard model used worldwide for the calibration of the aircraft gauges and which is based on experimental data.

Once there is reasonable confidence that the tree ring signal reflects a temperature signal, and then a calibration is performed using the derived tree ring data and instrumented temperature data.

The GCAM team changed their historical calibrations to the compiled input data described above, while the AIM, IMAGE and MESSAGE teams used a multiplier, linearly converging to one over the 21st century, to ensure consistency with historical data for the year 2000.

Now we find potential SST data that while it may not necessarily change some of the total delta C, it could change the shape of the curves that are used for the calibration period.

«Magic with numbers» is always accomplished by either inventing your data or massaging what data you have, unreliable at best given the time spans involved the equipment available, the precision, repeatable accuracy and calibration of the equipment used to collect the data along with the number of people doing the measurements, all of which are accomplished somewhat differently.

As I have also documented (and you have failed to respond to), by his own admission Willis used none of this calibration data to decide which floats to remove from his data set — he only removed floats which contradicted his colleagues» models (by showing too much warming).

Does anyone understand this culling process that uses «calibration data» and «verification skill» which happens to remove all negative trend data, but only half of the positive trend data?

-------- http://iopscience.iop.org/1748-9326/8/1/014013 Predictability of twentieth century sea - level rise from past data However, in combination, the use of proxy and tide gauge sea - level data up to 1900 AD allows a good prediction of twentieth century sea - level rise, despite this rise being well outside the rates experienced in previous centuries during the calibration period of the model.

The temporal overlap of the NOAA - 17 and -18 instruments is used to introduce a small additive adjustment to the channel - 2 calibration of the latter resulting in a consistent record with increased data density.

Canadian statisticians Steven McIntyre and Ross McKitrick demonstrated errors in Mann's statistical analysis and in the use of certain tree - ring data for calibration.

«Observations used to condition the models ought to be explicitly stated, or there is the risk of doubly calling on data for purposes of both calibration and evaluation.»

If the climate models use hindcasting to Hadley or Giss pre-1979 temperature series as any sort of calibration, they are calibrating to a CREATED TREND, created using cooling adjustments to pre-1979 data.

It should * also * be noted that we used essentially none of these data in the multiproxy Mann / Bradley / Hughes (MBH) reconstruction, and that the MBH reconstruction tracks the instrumental record quite well through the very end of our calibration interval (1980 — it stops then because there are far fewer paleo records available after 1980).

If a good calibration can be obtained, then the satellite data could (and should) be used in lieu of the radiosonde data.

I haven't seen your methodology properly described but it appears that your model is based on some kind of statistical calibration with past data that is used to forecast future conditions.

The RegEM algorithm of Schneider (9) was used to estimate missing values for proxy series terminating before the 1995 calibration interval endpoint, based on their mutual covariance with the other available proxy data over the full 1850 — 1995 calibration interval.

Chris stated they are calibrated to the radiosonde data, but did not elaborate if the calibration for the humidity measurement was good enough to allow satellite data to be used in lieu of radiosonde data.

And since we know the pre Argo OHC data is poor to nonexistant (xbt calibration being but one example), it means the attribution problem is likely insoluble using observational means until many more ARGO decades have passed, at least one more full stadium wave.

The standard measure of reconstructive skill, the «reduction of error» metric («RE») used by MBH98, was used to evaluate the fidelity of the resulting reconstruction using 19th century instrumental data that are independent of the calibration (RE < 0 exhibits no skill, while RE = -1 is the average value for a random estimate).

One technique to demonstrate credibility is by assessing how well the statistical model does on data that was not used in the calibration.

The MBH98 reconstruction is indeed almost completely insensitive to whether the centering convention of MBH98 (data centered over 1902 - 1980 calibration interval) or MM (data centered over the 1400 - 1971 interval) is used.

This second term is usually small for a date when the proxies are well within the range represented by the calibration data, but may become large when the equation is used to extrapolate to proxy values outside that range.

These assumptions can also be checked using the training and calibration periods, and often more complicated regression methods can be used to adjust for particular features in the data that violate the assumptions.

Calibration and tuning of coupled Human — Earth System models, as indicated above, could take advantage of optimal parameter estimation using advanced Data Assimilation, rather than following the more traditional approach of tuning individual parameters or estimating them from available observations.