Cyclic changes of climate and major commercial stocks of the Barents Sea

Abstract

Spectral analysis of 100-year time series of Arctic surface temperature (Arctic dT), mean temperature of 200-m water column along the Kola meridian and global surface temperature anomaly (Global dT) was performed. It is shown that climatic indices of the Arctic region undergo long-term 50Á70-year fluctuations similar to fluctuations of Global dT and Arctic dT for the last 1500-year reconstructed period and the recent 140 years of instrumental measurements. Long-term changes of Atlantic spring-spawning herring and Northeast Arctic cod commercial stocks also show 50Á70-year fluctuations that are synchronous with the fluctuations of climatic indices. A simple stochastic model is suggested that makes it possible to predict the probable trends of basic climatic indices and populations of major commercial fish species for up to 20Á30 years into the future. The results obtained also elucidate the old discussion: which factor is more influential on the longterm fluctuations of major commercial stocks, climate or commercial fisheries? We think that what we have learned is that climate is of priority, but which factor(s) cause(s) what, for which species, seems as yet unanswered.

Kittiwake diets and chick production signal a 2008 regime shift in the Northeast Pacific

“…Baumgartner et al 1992, Klyashtorin 1997, Zhen-Shan & Xian 2007. While 60 yr is a convenient period to use for modeling purposes (Loehle & Scafetta 2011, Zwolinski & Demer 2012, examination of empirical data of various types and durations leads different authors to speak of a '50-year cycle' (Chavez et al 2003), a 'quasi 60-year cycle' (Mazzarella & Scafetta 2011), a '50−70 year cycle' (Minobe 1997, 1999, Mantua & Hare 2002, Klyashtorin et al 2009), a '50−79 year cycle' (Humlum et al 2011), or a '50−75 year cycle' (Ware 1995). Given decidedly noisy signals, long periodicities relative to human lives and datasets, possible lag times, and limited or no understanding of mechanisms, it remains to be shown to what extent such reports are describing either the same or multiple, unconnected phenomena.…”

“…Time will tell whether the model of a ~60 yr cycle holds up in this instance. Klyashtorin (1997Klyashtorin ( , 2001) and Klyashtorin et al (2009) find strong correlations between global commercial fish production and climate indices, including a global temperature anomaly computed for instrumental data collected since ~1850 and another synoptic indicator called the ACI. The ACI summarizes annual patterns of atmospheric pressure and air mass transfer over the Atlantic−Eurasian region.…”

“…One school of thought (IPCC 2007) maintains that warming since ~1970 is primarily attributable to human activity, while another (ZhenShan & Xian 2007, Klyashtorin et al 2009, Scafetta 2010, 2012, Humlum et al 2011, Loehle & Scafetta 2011 argues that natural cycles of climate variation are equally or more important. A third point of view is that the worst effects of human-caused warming are still to come as methane release from melting permafrost and other amplifying feedbacks cause runaway increases in global temperature and sea level (Lawrence & Slater 2005, Hansen & Sato 2012.…”

Biodiversity in concert: Common, uncommon, and new species

“…In Marine Biology Research, several articles have dealt with recently observed abundance fluctuations in commercially important fish species viewed from ecosystem-, fisheries-and/or climate change-oriented perspectives (e.g. Tsikliras 2008;Gjøsaeter et al 2009a;Klyashtorin et al 2009). One preliminary conclusion from these studies is that in marine habitats human impacts on common species may still be reversible.…”

“…However, there is a pressing need to better understand long-term demographic trends and interactions among natural and human-induced factors towards securing sustainable management (e.g. Husa et al 2008;Klyashtorin et al 2009;Norderhaug & Christie 2009).…”