Deterministic signals in USA precipitation records: Part II

Abstract

The ideal aim before the mind of the physicist is to understand the external world of reality. But the means which he uses to attain this end are what are known in physical science as measurements, and these give no direct information about external reality. They are only a register or representation of reactions to physical phenomena. As such they contain no explicit information and have to be interpreted. As Helmholtz said, measurements furnish the physicist with a sign which he must interpret, just as a language expert interprets the text of some prehistoric document that belongs to a culture utterly unknown. The first thing which the language expert assumes-and must assume if his work is to have any practical meaning-is that the document in question contains some reasonable message which has heen stated according to some system of grammatical rules or symbols. In the same way the physicist must assume that the physical universe is governed by some system of laws which can he understood, even though he cannot hold out to himselfthe prospect of being able to understand them in a comprehensive way or to discover their character and manner of operation with anything like a full degree of certitude (authors' italics). Max Planck (1932)ABSTRACT Power spectra of 1203 American rainfall records show evidence for two peaks with mean periods of 18.5 1.8 and 106 & 0.6 years, and statistical tests show that both are significant at confidence levels of 99.9 per cent. These are identified as induced by the luni-solar 18.6-year constituent tide and a 10-1 1-year solar cycle variation in the sun's luminosity of the order of 0.1 per cent. Amplitude and phase of the 18.6 year wavetrains are highly non-stationary, and abrupt 180" phase changes in wave polarity are often observed. Wave maxima/minima are generally in phase or out of phase with epochs (epochs are dates of maximum in tidal forcing which occurred at 1898.9, 1917.5, etc.). Polarity maps show that for epochs 1898.9,1917.5,1936.1 and 1954.7 the major part of the nation's landmass experienced droughty conditions, which reached a maximum in both amplitude and areal extent at 1936.1, the Dust Bowl era. At mid-epoch 1964.0 and epoch 1973.3 so many waves changed phase by 180" that the major part ofthe landmass was wet at the epoch. Analogous phenomena have been found in tree-ring data from several continents, and implications for economic science are briefly discussed.

Droughts near the northern fringe of the East Asian summer monsoon in China during 1470–2003

“…The quasi-10 year and 20-30 year timescales are close to that of the solar activity (e.g. Mitra et al 1991;Currie and O'Brien 1992;Linderholm 2001). Recently, Qian and Lu (2010) found solar radiation cycles at the 22-year timescale from 1850 to 2000, which may be linked with the 20-30 year band in Fig.…”

Variance contribution of luni‐solar and solar cycle signals in the St Lawrence and Nile river records

“…When the mean spectrum of hundreds of series is computed the period in individual spectra vary from 16 to 22 years, but the mean period is close to 18.6 years (e.g. Currie and O'Brien, 1992;Currie, 1993a).…”

“…More recently, Currie (1991aCurrie ( -c, 1992a studied the terms in 436 tree-ring chronologies from North and South America, Europe, New Zealand, Tasmania, and South Africa, and Currie and O'Brien (1992), following their earlier eight papers on regional studies of USA precipitation, reprocessed 1200 American rainfall records finding both terms significant at confidence levels of 99.9 per cent. Currie (1993b) confirmed and ex-tended evidence given by Tyson (1986) for both terms in South African rain-gauge data, and Currie (1993a) presented a final and comprehensive study of both signals in 1200 American air temperature records (both significant at 99.9 per cent confidence levels).…”

Luni‐solar 18.6‐ and 10—11‐year solar cycle signals in H. H. lamb's dust veil index

“…Figure 3(a) shows the Y-W spectrum of dviA for an AR(21) autoregressive model of order L = 21; it is visually identical to the MESA spectrum in Figure 2(a) because the length of the series was 457 years. Yet, as Currie and OBrien (1992) noted, the two methods are based on diametrically opposed concepts. With MESA the data are assumed to be noiseless (i.e.…”