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1
Content available Instability of the environment at the end of the Eemian Interglacial as illustrated by the isopollen maps for Poland
Kupryjanowicz M., Granoszewski W., Nalepka D., Pidek I. A., Walanus A., Balwierz Z., Fiłoc M., Kołaczek P., Majecka A., Malkiewicz M., Nita M., Noryśkiewicz B., Winter H.
Geological Quarterly
|
2016
|
Vol. 60, No. 1
225--237
EN
Many terrestrial pollen profiles from Poland (and a few pollen records from other parts of Central Europe) show the end of the last interglacial (Eemian, MIS 5e) to have been characterized by climatic and environmental instability. This is expressed by a strong, rapid cooling in the middle part of the pine phase ending this interglacial (E7 regional pollen assemblage zone), and then a re-warming at the very end of this phase, immediately before the transition to the glacial conditions of the last glaciation (Vistulian, Weichselian, MIS 5d). We have characterized the regional distribution of these climatic fluctuations in Poland on the basis of isopollen maps prepared for the Eemian Interglacial based on palynological data from 31 Polish pollen profiles. These maps show unequivocally that the intra-interglacial cooling at the end of the Eemian Interglacial was a transregional phenomenon, which was reflected very clearly by a temporary openness of vegetation across the whole of Poland. It was associated with a distinct decrease in pine forest areas and an increase in birch forests and open communities of cold steppe type with a domination of Artemisia. The pronounced climate and environment instability during the last phase of the Eemian Interglacial may be consistent with it being a natural phenomenon, characteristic of transitional stages. Taking into consideration the currently observed global warming, coinciding with a natural cooling trend, the study of such transitional stages is important for understanding the underlying processes of climate change.
2
Content available Selected economic factors impacting tourist travel in Poland between 2000 and 2012 and a forecast for 2013-2017
Kućmierz P., Mazurkiewicz Ł., Walanus A.
Geotourism / Geoturystyka
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2014
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nr 1
25--32
EN
The paper presents an analysis of tourist travel in Poland during the 2000-2012 time period and predictions for years 2013-2017. Since 2000 the amount of travelling Polish citizens has declined. Various factors may have impacted this state of matters e.g. the economic crisis or increasing the VAT rate. The biggest decline in tourist travel was observed between 2007 and 2009 and in 2011. On the other hand, the factor which increased the number of visits between 2007 and 2009 may have been the Euro 2012 championship, organized by both Poland and Ukraine. The paper presents a "eurosensitivity" factor, which describes the increase in people visiting selected voivodeships during 2012, primarily due to the Euro 2012 championship. According to the calculations, the voivodeship which benefited from the highest increase was Małopolska. The article also presents an estimation of travel for years 2013-2017.
3
Content available Regional maps of rate of change of pollen percentage as a tool for climate change visualization
Walanus A., Nalepka D.
Geological Quarterly
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2013
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Vol. 57, No. 2
353–-356
EN
Isoline maps of percentage of pollen, obtained for different time horizons through the Holocene, are a typical tool for palaeobotanical studies. In connection with the West Carpathian project the authors have developed the idea of graphically presenting on the map a rate of change of the pollen percentage. Such a map is based on the data from two time horizons. The precision of such a type of map, which shows the %/change/100 yrs, and in which the value can be negative as well as positive, is lower that of a typical isopollen map. However, this type of map gives a direct insight into changes in the plant cover, which are related to climate change.
4
Content available remote Praktyczne testowanie istotności różnicy wartości średnich w seriach opadowych
Twardosz R., Walanus A.
Przegląd Geofizyczny
|
2011
|
Z. 1-2
81-97
PL
W badaniach klimatologicznych często porównuje się średnie sumy opadów w porach roku lub typach cyrkulacji. Jednak nie zawsze dokonuje się oceny istotności różnicy średnich sum. W pracy zaproponowano dwa odmienne sposoby testowania istotności różnic średnich dobowych opadów wraz z podaniem przykładów stosowania testów przy wykorzystaniu standardowych formuł arkusza MS Excel. Pierwszy ze sposobów polega na transformacji danych za pomocą przekształcenia Boxa-Coxa. Drugi natomiast opiera się na zastosowaniu testów istotności niezależnych od rozkładów, tj. testu serii Walda-Wolfowitza, testu sum rang U Manna-Whitneya i testu zgodności Kołmogorowa-Smirnowa. Podane są algorytmy realizacji wszystkich testów za pomocą standardowych formuł arkusza MS Excel (niezależnych od wersji programu).
EN
In climate research it is frequent to search for the difference in precipitation in different circumstances. However, because of high skewness of the probability distributions of the daily precipitation the standard statistical procedures, which assume normality are inappropriate here. Two approaches to the problem are considered, the application of Box-Cox transform to get normal distribution, and application of the standard distribution-independent tests. Namely the Wald-Wolfowitz, Mann-Whitney U, and Kolmogorov-Smirnov tests are considered to be especially useful. The algorithms for all tests are given to perform them in the standard MS Excel spreadsheet (practically independent on the program version, with no use of Visual Basic).
5
Content available Zdolność rozdzielcza metody radiowęglowej
Walanus A.
Przegląd Geologiczny
|
2009
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Vol. 57, nr 11
961-963
6
Content available remote Drawing the optimal depth-age curve on the basis of calibrated radiocarbon dates
Walanus A.
Geochronometria
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2008
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Vol. 31
1-5
EN
The radiocarbon determination of age has the form of a complicated probability density function. In some cases however it is possible to exploit it in a precise way, in drawing the depth-age curve when a stratigraphic sequence of 14C ages is available. It is also possible to use this function in drawing the depth-age curve by hand. The necessary additional constraint on the depth-age curve adopted here is the simplicity of its shape, namely the low curvature.
7
Content available remote Groups of too close radiocarbon dates
Walanus A.
Geochronometria
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2006
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Vol. 25
5-10
EN
In the archaeological and palaeogeographical literature, it is relatively frequent to find groups of radiocarbon dates of too close values. Too close means here that the dates exhibit no other variability than that of random origin, quantified by the given measurement errors. The chi-squared statistic seems to be appropriate to test, if the given group of dates is of random variability, of larger variability (what is typical) or of too small variability. The last case is hard to explain.
8
Content available Numerical correlation of many multidimensional geological records
Walanus A., Nalepka D.
Annales Societatis Geologorum Poloniae
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2006
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Vol. 76, No 2
215-224
EN
It is frequent task to correlate profiles or cores basing on different measurements performed on the series of samples. The difficulty arises when there are many profiles and none is the main or reference one. The reason is that the number of possible correlations grows exponentially with the number of profiles. To resolve the problem a Monte Carlo method is adopted here, what makes it very probable to discover the best correlations in a reasonable amount of computing time. The quality of a correlation is measured by a metric of dissimilarity of the samples. The final result, given in graphical form, has a form of lines connecting correlative samples from different profiles. The number of lines (correlations across profiles) is user-defined and can vary from one to dozens. The number of profiles, samples, and variables depends only on the computational resources. Large problems need longer computation times to achieve stable results.
PL
Korelowanie dwóch lub kilku sekwencji próbek z profilu, na podstawie wyników różnych pomiarów wykonywanych dla próbek, jest jednym z najczęściej wykonywanych zadań. Jednak w sytuacji korelow nia większej liczby równorzędnych profili, ze względu na wykładniczo rosnącą z liczbę profili liczbę możliwych korelacji, zadanie staje się trudne. Zaproponowane rozwiązanie ograniczenia czasu poszukiwania najlepszej korelacji wykorzystuje metodę Monte Carlo. Otrzymany wynik korelowania, aczkolwiek niekoniecznie najlepszy, najprawdopodobniej będzie bardzo bliski optymalnej korelacji. Jakość korelacji mierzona jest za po - mocą współczynnika niepodobieństwa próbek. Końcowy wynik działania omawianego programu przedstawiany jest w postaci graficznej, w postaci pewnej (zadanej) liczby linii łączących po - dobne poziomy. Liczba korelowanych profili, próbek i zmiennych zależy jedynie od wielkości pamięci komputera. Czas zawsze można dowolnie ograniczyć, jed nak warto wtedy sprawdzi? stabilność uzyskanego wyniku obliczeń.
9
Content available remote Elementarne podejście do problemu cykliczności w zjawiskach klimatycznych
Walanus A., Prokop P.
Przegląd Geofizyczny
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2004
|
Z. 1-2
57-69
EN
The paper presents an elementary approach to the problem of periodicity in climatic data. The basic method applied in this study is the Fourier analysis (FFT). The periodicity was searched on the basis of long term instrumental precipitation data for 46 European stations for the period of 1832-1992, and for W-E and N-E transects for the period 1864-1992. The evidence of cycles in the range 2 to 128 years was examined in terms of their being of natural variability of climate system, or the result of external forcing. The complexity of the climate system with large number of degrees of freedom, and the unstable nature of atmospheric circulation causing difficulties in distinguish real periodicity from noise. The result show that it is relatively easy to obtain quasi-periodicity in climatic data however it is very difficult to find them statistically significant. We can said that disturbances in climate system can produce a quasi-periodic response which behaves sometimes as an oscillation before disappearing back into the noise or appearing in other place and other time.
10
Content available Integration of Late Glacial and Holocene pollen data from Poland
Walanus A., Nalepka D.
Annales Societatis Geologorum Poloniae
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2004
|
Vol. 74, No 3
285--294
EN
Quaternary palynological data are stored in tables which are typical computer database objects. The individual pollen table, in order to be integrated with other tables using computer-based methods, has to be attributed with (1) geographical coordinates, (2) dates attached to each row (sample) of the table, and (3) taxa names, common to all tables, attached to each column. In this paper, integration of individual lists of palynological taxa is shortly described, and some remarks are given on extracting data for selected time slices. The problem of dating of all pollen spectra, while few radiocarbon dates are available in the profile, is considered. Some mathematical models of age-depth relation are proposed, as well as incorporation of information derived from lithology of the profile. The algorithm of integration (averaging) of pollen percentages on the map of Poland is discussed. The techniques of bootstrap and so-called removed residuals are proposed as tools for assessment of reliability of isopollen lines. A possibility of construction of migration (rate of change) maps is also mentioned. The presented algorithm has been used to obtain hundreds of isopollen maps for the Holocene in the area of Poland .
11
Content available remote Istotność statystyczna wniosków z analiz ilościowych na przykładzie badań górnego czwartorzędu
Walanus A.
Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie
|
2000
|
T. 26, z. 4
469-527
PL
Statystyka matematyczna jest jednym z narzędzi geologii, wykorzystywanym szczególnie w badaniu młodszych okresów, gdzie szerzej stosowane są metody ilościowe. W przedstawionym tekście, który jest podsumowaniem kilkunastu opublikowanych prac, zawarta jest propozycja pewnego podejścia do wnioskowania statystycznego. Kluczowe w tym spojrzeniu jest pojęcie istotności statystycznej, którego sens rozszerzono dla zwiększenia jego stosowalności w geologii. Wskazano kilka metod weryfikacji poprawności wyznaczania poziomu istotności. Podano pewne algorytmy i zasady postępowania, nie wymagające ani zaawansowanej matematyki ani technik obliczeniowych wykraczających poza możliwości arkusza kalkulacyjnego. Materiał merytoryczny zilustrowano przykładami z prac badawczych dotyczących skal czasu od 15000 lat do 5 dni
EN
Mathematical statistics is an unavoidable tool in modern geology, especially in Quaternary and Recent period, where quantitative approach based on measurements is widely applicable. Statistical methods consists not only of more or less advanced calculations but involves also difficult reasoning of special statistical kind. Proposed here, the way of statistical thinking is based on the, slightly modified idea of statistical significance level. As applied to the complicated environment of geological quantities, which are mutually interrelated and dependent on many unknown influences, significance level calculation result frequently only in rough estimation of reliability of suggested thesis. Some methods are proposed here to avoid gross errors in statistical significance level appreciation. Some sources of such errors are indicated. Neither advanced mathematics is necessary in the given approach nor sophisticated calculations (Excel is enough). Examples are presented, which came from scientific research of Late Glacial and the Holocene period, as well as from historical, up to the modern data
12
Content available remote O szkodliwości pojęcia nieskończoności [Listy do redakcji]
Walanus A.
Postępy Fizyki
|
1998
|
T. 49, z. 1
51-51
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