The latter is further filtered with a 80-year running averages filter to obtain what we call the steady variation (E80).
jerks are part of a more complex behavior of the field, namely the superposition of variations at the 22- and ~80-year timescales on a steady variation, as a result of superimposed surface effects of core processes at several timescales.
The jerks should be regarded as parts of a more complex behavior of the field, namely the superposition of variations at the 22- and ~80-year timescales on a steady variation, as a result of superimposed surface effects of core processes at several time scales.
Secular variation studies developed by Demetrescu and Dobrica (2005, 2014) and Dobrica et al. (2013) on long time series (100 150 years) of observatory data showed that the surface field and its SV are constituted of oscillations at time scales of ~ 11, ~ 22 and ~ 80 years, which are superimposed on a (quasi linear trend denoted steady variation.
Several conclusions could be drawn regarding the secular change of the internal field, having at hand the longer time perspective on data plotted in Fig. 8: (1) the first time-derivative does not show jerks, but display extrema of the combined ~80-year, 22-year, and steady variations; this was first shown on D data by Demetrescu and Dobrica (2005, 2013).
Chronic pain activity induces steady variations in interneuronal transmission that could alter motor strategies [ 16].
Such comparisons revealed significant signatures (with steady variations of mean values, either increasing or decreasing) between the three following groups: a merged group associated with hyperthermophiles and thermophiles (HTH-TH); a merged group associated with prokaryotic mesophiles and psychrophiles (PMES-PSYC) and finally eukaryotes (EUK).
Correlations increase over time, until at steady state, variation in growth rates is tightly correlated with variation in lysis rates, such that no net variation in fitness (net density change) is observed.
The sequential spatial color-patterns obtained in steady periodical variation process were similar to the transitional color patterns observed in the decolorization process.
Then, for each degree n, the improvement brought by assuming some steady secular variation acting on the field during the δt = 5 year period between t0 = 2004 and t = 2009, relatively to assuming no secular variation can be written as: (4).
We found out, for instance, that page-size global maps, as those posted at http://www.ngdc.noaa.gov/wist/magfield.jsp, are dominated by the steady field variation, while regional maps as those of the present paper are influenced by the geographical pattern of the 22-year and ~80-year variations.
