Sentences with phrase «with multidecadal variability»

Clearly the higher frequencies dominate in some indices, but the results have been pretty consistent with the multidecadal variability being shared by all network indices.

Not exact matches

The recent slowdown in global temperature increase is consistent with internal Pacific and Atlantic multidecadal variability.

Furthermore, since the end of the 19th century, we find an increasing variance in multidecadal hydroclimatic winter and spring, and this coincides with an increase in the multidecadal North Atlantic Oscillation (NAO) variability, suggesting a significant influence of large - scale atmospheric circulation patterns.

AWP variability occurs on both interannual and multidecadal timescales as well as with a secular variation.

The AWP multidecadal variability coincides with the signal of the AMO; that is, the warm (cool) phases of the AMO are characterized by repeated large (small) AWPs.

Mike's work, like that of previous award winners, is diverse, and includes pioneering and highly cited work in time series analysis (an elegant use of Thomson's multitaper spectral analysis approach to detect spatiotemporal oscillations in the climate record and methods for smoothing temporal data), decadal climate variability (the term «Atlantic Multidecadal Oscillation» or «AMO» was coined by Mike in an interview with Science's Richard Kerr about a paper he had published with Tom Delworth of GFDL showing evidence in both climate model simulations and observational data for a 50 - 70 year oscillation in the climate system; significantly Mike also published work with Kerry Emanuel in 2006 showing that the AMO concept has been overstated as regards its role in 20th century tropical Atlantic SST changes, a finding recently reaffirmed by a study published in Nature), in showing how changes in radiative forcing from volcanoes can affect ENSO, in examining the role of solar variations in explaining the pattern of the Medieval Climate Anomaly and Little Ice Age, the relationship between the climate changes of past centuries and phenomena such as Atlantic tropical cyclones and global sea level, and even a bit of work in atmospheric chemistry (an analysis of beryllium - 7 measurements).

Previous studies have found it to be well correlated with the low - frequency variations in the North Atlantic sea surface temperature associated with the Atlantic multidecadal variability (AMV).

- 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)

Three of these five intervals coincided with multidecadal hemispheric climate - regime shifts, which were characterized by a switch between distinct atmospheric and oceanic circulation patterns, a reversal of NHT trend, and by altered character of ENSO variability.

The Atlantic Multidecadal Oscillation (like other ocean oscillations) is a climate pattern with a mode of variability, which seems to naturally occur regardless of atmospheric CO2 levels.

The LIA was dominated by a ∼ 20 year AMO cycle with no other decadal or multidecadal scale variability above the noise level.

The BEST team found that greenhouse gases and volcanic eruptions could account for most of the observed temperature change, and suggest that the remainder of the variability is fairly consistent with the Atlantic Multidecadal Oscillation (AMO), an ocean cycle, and very little contribution from changes in solar activity (Figure 2).

«Bias might be introduced in cases where the spatial coverage is not uniform (e.g., of the 24 original chronologies with data back to 1500, half are concentrated in eastern Siberia) but this can be reduced by prior averaging of the chronologies into regional series (as was done in the previous section)... Eight different methods have been used... They produce very similar results for the post-1700 period... They exhibit fairly dramatic differences, however, in the magnitude of multidecadal variability prior to 1700... highlighting the sensitivity of the reconstruction to the methodology used, once the number of regions with data, and the reliability of each regional reconstruction, begin to decrease.

Moreover, 370 years of tropical cyclone data from the Lesser Antilles (the eastern Caribbean island chain that bisects the main development region for landfalling U.S. hurricanes) show no long - term trend in either power or frequency but a 50 - to 70 - year wave pattern associated with the Atlantic Multidecadal Oscillation, a mode of natural climate variability.

Multi-decadal oscillations plus trend hypothesis: 20th century climate variability / change is explained by the large multidecadal oscillations (e.g NAO, PDO, AMO) with a superimposed trend of external forcing (AGW warming).

«The global surface air temperature record of the last 150 years is characterized by a long ‐ term warming trend, with strong multidecadal variability superimposed.

It seems that every new climate scenario making the media over the past 20 years they always describe a warm future on a multidecadal scale ignoring a cool future as if variability didn't exist, but isn't scientific climatology primarily concerned with longer millenia time scales of a thousand years or more?

Necessary (but not sufficient) for a credible fingerprinting attribution is to understand the fingerprints associated with natural internal variability on multidecadal and longer timescales, which is essentially ignored.

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.

They clearly mention that the drop is neither explicable with aerosols nor with multidecadal ocean variability.

It is evident that the two curves equally well reconstruct the climate variability from 1850 to 2011 at the decadal / multidecadal scales, as the gray temperature smooth curve highlights, with an average error of just 0.05 °C.

Multidecadal variability in methane concentrations throughout the LPIH is weakly correlated or uncorrelated with reconstructions of temperature and precipitation from a variety of geographic regions.

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.

This interest in natural variability led to an irony: one of Mann's first papers, a collaboration with Jeffrey Park, provided evidence for the existence of a natural cycle, the Atlantic Multidecadal Oscillation, or AMO.

I'm not sure whether ~ 15 years is a long enough period to conclude that the model projections are seriously out of line with reality, given the existence of not very well quantified decadal and multidecadal internal variability in the real climate system.

Whereas each model demonstrates some sort of multidecadal variability (which may or may not be of a reasonable amplitude or associated with the appropriate mechanisms), the ensemble averaging process filters out the simulated natural internal variability since there is no temporal synchronization in the simulated chaotic internal oscillations among the different ensemble members.

The global surface air temperature record of the last 150 years is characterized by a long - term warming trend, with strong multidecadal variability superimposed.

The reason this choice matters is that this bias correction will be applied to the 21st century simulations, and the bias corrections are useless if you are merely correcting for multidecadal variability that is out of phase with the observations.

The last low - ice event related to orbital forcing (high insolation) was in the early Holocene, after which the northern high latitudes cooled overall, with some superimposed shorter - term (multidecadal to millennial - scale) and lower - magnitude variability.

The observed internal variability so estimated exhibits a pronounced multidecadal mode with a distinctive spatiotemporal signature, which is altogether absent in model simulations.

This model's forced response agrees very well with the observed surface temperatures averaged over the North Atlantic, so in this model one doesn't need to invoke internal multidecadal variability to match these observations.