Sentences with phrase «large statistical uncertainties»

Not exact matches

However, in order to know that such a deviation (if observed) is not just a statistical fluctuation, the difference must be conclusive — it must be at least five times larger than the experimental and theoretical uncertainties.

1 degree is much larger than the statistical uncertainty.

The model results (which are based on driving various climate models with estimated solar, volcanic, and anthropogenic radiative forcing changes over this timeframe) are, by in large, remarkably consistent with the reconstructions, taking into account the statistical uncertainties.

In other words, it is possible that the the climate system does exhibit some kind of long - term chaos in some circumstances, but that the forcing is strong enough to wipe out any significant uncertainty due to initial conditions — at least if one is content to forecast statistical quantities such as, for example, decadal mean January temperatures in some suitably large region, or perhaps temperature variances or quartiles taken over a similar period.

The IPCC range, on the other hand, encompasses the overall uncertainty across a very large number of studies, using different methods all with their own potential biases and problems (e.g., resulting from biases in proxy data used as constraints on past temperature changes, etc.) There is a number of single studies on climate sensitivity that have statistical uncertainties as small as Cox et al., yet different best estimates — some higher than the classic 3 °C, some lower.

So: The study finds a fingerprint of anthropogenic influences on large scale increase in precipitation extremes, with remaining uncertainties — namely that there is still a possibility that the widespread increase in heavy precipitation could be due to an unusual event of natural variability.The intensification of extreme rainfall is expected with warming, and there is a clear physical mechanism for it, but it is never possible to completely separate a signal of external forcing from climate variability — the separation will always be statistical in nature.

I will argue that the uncertainties make it necessary to look at many different methods for downscaling (regional climate models and statistical downscaling) as well as the largest possible range of (sensible) GCMs.

If we have inadequate sampling, and short time intervals, the statistical uncertainties from random fluctuations and random measurement errors can be large, but would tend to cancel out as the number of observations and length of time increases.

To estimate the uncertainty range (2σ) for mean tropical SST cooling, we consider the error contributions from (a) large - scale patterns in the ocean data temperature field, which hamper a direct comparison with a coarse - resolution model, and (b) the statistical error for each reconstructed paleo - temperature value.

On his blog, tamino does the statistical analysis of the BEST data and finds that because the timeframe in question is so short, the uncertainty is too large to say for certain that the short - term trend in question is any different than the long - term trend.

Our analyses also highlight the large amount of uncertainty in statistical projections of Polar Bear abundance and the sensitivity of projections to plausible alternative assumptions.

Such solecisms throughout the IPCC's assessment reports (including the insertion, after the scientists had completed their final draft, of a table in which four decimal points had been right - shifted so as to multiply tenfold the observed contribution of ice - sheets and glaciers to sea - level rise), combined with a heavy reliance upon computer models unskilled even in short - term projection, with initial values of key variables unmeasurable and unknown, with advancement of multiple, untestable, non-Popper-falsifiable theories, with a quantitative assignment of unduly high statistical confidence levels to non-quantitative statements that are ineluctably subject to very large uncertainties, and, above all, with the now - prolonged failure of TS to rise as predicted (Figures 1, 2), raise questions about the reliability and hence policy - relevance of the IPCC's central projections.