Long time series

Reference materials are homogeneous, stable substances whose properties are sufficiently established as to make them useful for calibrating analytical instruments or validating measurement techniques. High-quality reference materials not only provide essential support for large-scale research studies, but also ensure accuracy of long time-series measure-... 

Keywords Climate change, Glacier, Long time series, Precipitation, Runoff... 

Total ozone observations have been collected since 1992 by means of Brewer spectrophotometry at Rome (41.9°N, 12.5°E, 60 m a.s.l.) and lspra (45.8°N, 8.63°E, 240 m a.s.l.). A filtering technique is applied to the Dobson ozone long time series of Vigna di Valle (42.08°N, 12.22°E, 262 m a.s.l.), Arosa (46.78°N, 9.68°E, 1840 m a.s.l.) and Lerwick (60.13°N, 1.18°W, 80 m a.s.l.) and to the Italian Brewer ozone data, in order to investigate on different time scales [1]. The aim of this analysis is to single out any effective ozone trend, together with the role of ozone fluctuations due to weather patterns, at the selected Northern Hemisphere middle latitudes sites. 

The Brewer daily total ozone measurements from January 1992 up to April 1998 have been analysed to investigate the temporal behaviour at Rome and lspra. The Dobson total ozone data are derived from the monthly long time series of Vigna di Valle (50km north of Rome) for the years 1957-1998, Arosa (170km north-west of lspra, Swiss Alps) for the time period 1926-1998 and Lerwick (Scotland) for the time interval 1957-1998. The Dobson data come from the World Ozone and Ultraviolet Radiation Data Centre (WOUDC). 

The Rao and Zurbenko technique (described in [2] and [3]) is applied to the Italian Brewer data sets and to the ozone long time series of Vigna di Valle, Arosa and... 

In order to assess the O3 trend, a well-known statistical methodology, based on the Mann-Kendall-Sneyers and Pettitt tests (described in [4] and [5]), is applied to the long time series, not filtered by means of the Rao and Zurbenko technique. A significance level of 95% is chosen to interpret the results. The analysis shows the existence of a negative trend of 2.7% every ten years, from 1979 to 1998, for Arosa and a negative... 

This embedding theorem holds irrespective of the choice of the delay time T if one could observe an infinitely long time series at infinitesimally small resolution. 

Schinke, H., Matthaus, W, 1998. On the causes of major Baltic inflows—an analysis of long time series. Continental Shelf Research, 18, 67-97. 

For each grid point in the Baltic Sea and Kattegat, time series of 369 x 24 -F 1 = 8857 hourly values of water levels in the period from 1.1.2005 1 00 UTC to 5.1.2006 0 (X) UTC were compiled and analyzed harmonically. By choosing this long time series of well over 1 year, it has been made sure that aU essential tidal constituents were recorded individually the differences between the angular velocities are all greater than 360°/8856 h 0.04065°/h. 

Numerically integrate the Rossler system for a = 0.4, 6=2, c = 4, and obtain a long time series for x(f). Then use the attractor-reconstruction method for various values of the delay and plot (x(f), x(f + t)). Find a value of t for which the reconstructed attractor looks similar to the actual Rossler attractor. How does that T compare to typical orbital periods of the system ... 

P.J. Neale, J.F. Tailing, S.I. Heaney, C.S. Reynolds, J.W.G. Lund (1991). Long time series from the English Lake District Irradiance-dependent phytoplankton dynamics during the spring maximum. Limnol Oceanogr., 36, 751-760. 

Invest in central databases for hydrological, hydrochemical and hydrobiological data to safeguard data sets, especially long time series, and to enable model development and upscaling to the regional and continental levels. 

In the case of Fourier analysis, the coherence critical value is independent of the processes to be compared, if they sufficiently well follow a linear description [1, 15]. This independency, however, holds exactly only in the limit of long time series. As wavelet analysis is a localized measure, this condition is not fullfilled. Hence, for different AR[1] processes (from white noise to almost nonstationary processes), we found a marginal dependency on the process parameters. 

A control series of nectar honey types was collected during the summer months from 1990 to 1996 from the whole Croatian territory. Since 1993, samples of honey have been collected regularly in the summer and early autumn from the Gorski Kotar area, Croatia. A long-time series of various types of honeydew honey and heather honey was collected in Austria, Germany, and Slovenia from 1952 through 1995. 

The spectral estimators provide a means to compute vibrational spectra from molecular dynamics results (from the time series of a correlation function) to any desired resolution [2]. This eliminates much of the negative aspects of the nonparametric methods, such as the standard fast Fourier transform (FFT) that needs a very long time series for good resolution (the resolution is 1/t, where t... 

The parameter estimates are then obtained by maximising either Eqs. (5.88) or (5.89). The result given by Eq. (5.89) is called the exact log-likelihood function. However, when dealing with a long time series with many data points, it will be computationally expensive to compute the determinant and inverse required by the exact log-likelihood function at every iteration. Instead, the exact probability can be... 

The consequences of the maximum wave height distribution [Eq. (6.30)] are generally hard to verify, not only because Eq. (6.30) depends on the number of waves but also because large amount of data are required to characterize nonlinear effects. In the following discussion, we compare the above theories with a set of long time-series experimental data these data appear to be sufficiently long to make useful comparisons. 

As previously mentioned, for the climatic temporal variability at the different timescales to be assimilated into the models, the time series should comprise a period of time at least equal to the period to be simulated. Fortunately, hindcast techniques provide long time series, over 40 years, of climatic statistic descriptors (i.e., HIPOCAS UE project). 

The below Fig. 10.3, according to numerical study of Kazhdan et al. (1995), presents long-time series for the surface deformation T) and the amplitude A (dashed line) - normalized by their maximum absolute values - at a fixed location. It can be seen that oscillations of T) and A are highly correlated the amplitude of the short-scale convection follows the surface oscillations, being large beneath surface elevations and small under surface depressions. 

According to the theory of ergodicity, averaging a quantity over an infinitely long time series is identical to performing the statistical ensemble average ... 

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