Sentences with phrase «multidecadal climate»

But the observational estimate uncertainty includes measurement and related errors that are not present in the model estimate uncertainty (although these appear to be relatively unimportant in this case), while only the model estimates sample decadal / multidecadal climate system internal variability, which very possibly affects the TLC reflection — SST relationship.

The modes of natural internal variability of greatest relevance are the Atlantic modes (AMO, NAO) and the Pacific models (PDO, often referred to as IPO) of multidecadal climate variability, with nominal time scales of 60 - 70 + years.

Given that the past 30 — 50 years is a relatively short period for evaluating long - term trends, the SST trends themselves could be viewed as a manifestation of large - scale modes of multidecadal Pacific variability (e.g. Zhang et al. 1997; Deser et al. 2004) or as part of the century scale positive SST trends associated with climate change (e.g. Deser et al. 2010); it is likely that both multidecadal climate variability and climate change have contributed to the SST trend pattern evident in Fig. 9 and used to force the model.

Recent accelerated warming of the Arctic results from a positive reinforcement of the linear warming trend (due to an increasing concentration of greenhouse gases and other possible forcings) by the warming phase of the multidecadal climate variability (due to fluctuations of the Atlantic Ocean circulation).»

Our results have important implications concerning the influence of North Atlantic sea surface temperatures on East Asian climate, and provide support for the possibility of an AMO signature on global multidecadal climate variability.»

Mainstream convention on multidecadal climate stat inference is philosophically invalid.

The accessibility of deep ocean heat to the climate system tells us that the equilibration time relevant to multidecadal climate sensitivity estimates is longer than an interval based on upper ocean measurements, and so sensitivity will be underestimated if only the shorter interval is used.

- ARAMATE (The reconstruction of ecosystem and climate variability in the north Atlantic region using annually resolved archives of marine and terrestrial ecosystems)- CLIM - ARCH-DATE (Integration of high resolution climate archives with archaeological and documentary evidence for the precise dating of maritime cultural and climatic events)- CLIVASH2k (Climate variability in Antarctica and Southern Hemisphere in the past 2000 years)- CoralHydro2k (Tropical ocean hydroclimate and temperature from coral archives)- Global T CFR (Global gridded temperature reconstruction method comparisons)- GMST reconstructions - Iso2k (A global synthesis of Common Era hydroclimate using water isotopes)- MULTICHRON (Constraining modeled multidecadal climate variability in the Atlantic using proxies derived from marine bivalve shells and coralline algae)- PALEOLINK (The missing link in the Past — Downscaling paleoclimatic Earth System Models)- PSR2k (Proxy Surrogate Reconstruction 2k)

What we can say is that the three curves in the figure to the upper left give one plausible account of multidecadal climate, MUL, since 1850.

After all his filtering Vaughn Pratt still could not get rid of them and says that ``... multidecadal climate has only two significant components: the sawtooth, whatever its origins, and warming...» He does not understand the sawtooth and is wrong about warming.

My reason for asking is that my conclusion, namely the parameters resulting from fitting the model to multidecadal climate, seems not to depend significantly on whether one cuts off at 2010, 2000, 1990, 1970, or even 1950.

However if one chooses to interpret the last 50 years of MRES as somehow part of multidecadal climate, namely as extra upticks around 1970 and 2000 from the baseline set by 1850 - 1950, as I proposed in the first sentence of the conclusion, «plus a miniscule amount from MRES after 1950,» then I would think around a mK is fair when those upticks are included as part of «modern multidecadal climate.»

A prediction of «multidecadal climate to within a millikelvin» that ignores constraining factors, which result in a 2000 millikelvin difference, is a lousy prediction, Pekka — that was my point to Vaughan Pratt.

(Regarding 1860 - 2000 rather than 1850 - 2010, I have never considered the first and last decade as meaningful when talking about multidecadal climate; in fact I demonstrated this statistically on a climate blog in February 2010, some 18 months before Santer et al made a similar point in their paper on that topic.)

It follows that the two components are essentially all there is to recent multidecadal climate thus understood.

I should add that anyone who can separate multidecadal climate defined as F3 (HadCRUT3) into the sum of an oscillating component and a concave - downwards trend (the opposite of what I called Observed Global Warming which is concave - upwards) will have the immediate attention of a lot of people.

If I understood Mike Rossander's calculation as cited by Mike Jonas above, it shows that your poster linking human CO2 emissions to multidecadal climate in the past record does not hold water statistically.

The strictly deterministic multidecadal climate that you insist upon flies in the face of everything that is known about geophysical fluid dynamics vis a vis the discoveries by Lorenz of chaotic behavior.

If your analysis is correct then you have separated two independent effects: the AGW signal and a new mechanism whereby heat is transferred from the mantle to the crust, driving multidecadal climate.

Your original article clearly states «The hypothesis then is that multidecadal climate has only two significant components: the sawtooth, whatever its origins,.....».

I only know about multidecadal climate, Edim.

Because even if we'd never heard of CO2 we'd still have this separation of multidecadal climate between Figures 1 and 2 into an oscillating component and a rising component, whose upward - curvature has continually been getting steeper and shows no sign of abruptly turning into a downward curvature.

Vaughan Pratt, please will you issue a formal retraction of your poster «Multidecadal climate to within a millikelvin».

Hey, we got this thus understood model of recent multidecadal climate trends nailed to the millikelvin, so we can simply extrapolate to get the future alarming trends, and you all might want to wake up and start getting scared (see title of our poster).

I'm fitting a model of multidecadal climate, namely SAW+AGW, to HadCRUT3.

I am very grateful to Mike Rossander for proposing an alternative description of multidecadal climate, which I've been asking for ever since I posted on December 4.

The latter should be construed merely as a hypothesis about multidecadal climate (namely that it can be modeled in this way) that is in the running with other hypotheses.

I then described the thus - defined low - frequency components of HadCRUT3, namely as SAW + AGW + MRES, which I refer to as MUL for multidecadal climate.

If anyone knows of a good alternative hypothesis that isn't overfitted, i.e. that doesn't use 14 parameters to model MUL (or whatever you prefer to define as multidecadal climate) I'd be very interested to see it.

«We infer from this analysis that the only significant contributors to modern multidecadal climate are SAW and AGW, plus a miniscule amount from MRES after 1950.

VPmK aimed to show that «multidecadal climate has only two significant components», AGW and something shaped like a sawtooth.

A few days ago, on Judith Curry's excellent ClimateEtc blog, Vaughan Pratt wrote a post «Multidecadal climate to within a millikelvin» which provided the content and underlying spreadsheet calculations for a poster presentation at the AGU Fall Conference.

Following MR's calculation, the situation was that VP's exact same sawtooth method was shown to give exact same support to the negation of the hypothesis, that is, that multidecadal climate has only one significant component, the sawtooth, with no warming at all from AHH law.

manacker: If I understood Mike Rossander's calculation as cited by Mike Jonas above, it shows that your poster linking human CO2 emissions to multidecadal climate in the past record does not hold water statistically.

The hypothesis then is that multidecadal climate has only two significant components: the sawtooth, whatever its origins, and warming that can be accounted for 99.98 % by the AHH law as measured by the R2 of its fit to observed global warming (and could be brought even closer to 1 with a good story for MRES).

This forecast, when properly understood, is a trivial consequence of the main claim, which is that «two components» could describe «recent multidecadal climate thus understood».

The claim is restricted to multidecadal climate.

The one GT student that you have engaged, Angela Fritz, is a first year graduate student interested in the intersection of climate change and policy (she is not taking the hurricane seminar, but is taking the multidecadal climate variability seminar).

Kravtsov, S., M. G. Wyatt, J. A. Curry, and A. A. Tsonis, 2014: Two contrasting views of multidecadal climate variability in the twentieth century.

In the past, Gavin agreed with me on the very limited value of downscaling multidecadal climate predictions.

I don't know the Australian data very well, but multidecadal climate predictions are less reliable on a regional basis than globally.

Not exact matches

Saba and colleagues used population models to evaluate the relative influence of climate indices including the Atlantic Multidecadal Oscillation, the North Atlantic Oscillation, and the El Niño Southern Oscillation.

There are two big climate influences on hurricanes — the Pacific Ocean's El Niño / La Niña cycle and the Atlantic Multidecadal Oscillation (AMO).

University of Montana Professor John Kimball is among the team of researchers who published an article on Oct. 30 about their study on Nature magazine's website titled «Vegetation Greening and Climate Change Promote Multidecadal Rises of Global Land Evapotranspiration.»

Hopefully, more refined work with recent and future data, and incorporation of research into the coupling mechanisms themselves, will allow us to validate the model climate sensitivities to the various forcings, and confidently reproduce multidecadal internal climate modes.

Nonetheless, even if the substantial recent trend in the AO pattern is simply a product of natural multidecadal variability in North Atlantic climate, it underscores the fact that western and southern Greenland is an extremely poor place to look, from a signal vs. noise point of view, for the large - scale polar amplification signature of anthropogenic surface warming.

The Atlantic Multidecadal Oscillation (AMO), Pacific Decadal Oscillation (PDO), North Atlantic Oscillation (NAO), and El Niño - Southern Oscillation (ENSO) have all been found to significantly influence changes in surface air temperature and rainfall (climate) on decadal and multi-decadal scales, and these natural ocean oscillations have been robustly connected to changes in solar activity.

Using simulations of the last millennium to understand climate variability seen in palaeo - observations: Similar variation of Iceland - Scotland overflow strength and Atlantic Multidecadal Oscillation.

Multidecadal changes in Iceland Scotland Overflow Water vigor over the last 600 years and its relationship to climate.

«What if climate change appears to be just mainly a multidecadal natural fluctuation?»