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Ocena suszy meteorologicznej w 2015 roku w północnej części centralnej Polski z wykorzystaniem wskaźnika hydrotermicznego (HTC) w kontekście zmian klimatycznych

Kuchar L., Iwański S., Diakowska E., Gąsiorek E.

Infrastruktura i Ekologia Terenów Wiejskich

2017

nr I/2

257--273

W pracy przedstawiono symulacje i ocenę wskaźnika hydrotermicznego (HTC) Sieljaninowa w 2015 roku w kontekście warunków aktualnych i oczekiwanych zmian klimatu dla potrzeb rolnictwa. Dla wybranej stacji meteorologicznej w centralnej Polsce wygenerowano dobowe wartości temperatur powietrza i opadów dla warunków aktualnych i oczekiwanych zgodnie z trzema typowymi dla Polski scenariuszami GISS Model E, zakładającymi podwojenie koncentracji CO2 - co jest spodziewane w latach 2050-2060. Dla roku 2015 oraz dwóch 500-letnich serii temperatur powietrza i opadów obliczono w okresach kroczących 30-dniowych wskaźnik hydrotermiczny HTC w istotnych z punktu widzenie nawodnień okresach od kwietnia do września. Łącznie w każdym roku wyznaczono 154 wartości wskaźnika HTC. Przebieg średnich wartości wskaźnika hydrotermicznego przedstawiono na wykresach wraz z odchyleniami standardowymi, 90% i 50% obszarami ufności. W badaniach wykazano, że rok 2015 należał do lat suchych bądź bardzo suchych w większości całego okresu wegetacji. Podobnie oceniony byłby w latach 2050-60 przy założeniu scenariusza zmian klimatu GISS. W pracy wykazano również, że wskaźnik HTC w sytuacjach nagłych dużych opadów przeszacowuje ocenę suszy meteorologicznej (zawyża wartości wskaźnika HTC).

This paper attempts to evaluate a year 2015 from the point of view of present and future expected climate for the purpose of agriculture production using the hydrothermal index of Sieljaninov (HTC). Air temperature and total precipitation were simulated for conditions current and expected for a chosen meteorological station in Central Poland, according to the GISS Scenario (which is typical for Poland assuming the CO2 concentration doubles, as is expected for the years 2050-2060). The year 2015 and two 500-year daily temperature and rainfall series were used for computing the hydrothermal index of Sieljaninov, with a 30-day window for vegetation periods, from April to September. The simulated hydrothermal index was presented on a graph during the vegetation period as a course of means with standard deviations, and 50% and 90% critical area. The presented results show the year 2015 as dry or very dry within the vegetation period as well from the point of view of future climate changes according to the GISS Scenario. In case of heavy rainfall during the dry period of plant vegetation hydrothermal index show over estimation tendency.

The Effect of Hydrothermal Conditions on Oats Yields in East-Central Poland (1975–2005)

Radzka E., Jankowska J., Markowska M.

Journal of Ecological Engineering

2015

Vol. 16, nr 3

184--188

The objective of the work was to evaluate the effect of hydrothermal conditions on oats yields produced in east-central Poland. Hydrothermal conditions were determined based on the Sielianinov’s hydrothermal coefficient for nine IMGW (Institute of Meteorology and Water Management) stations located in the study area. The second data set consisted of oats yields compiled and published by the Main Statistical Office. Average yields as well as minimum and maximum yields were analysed. The relationship between oats yields and hydrothermal conditions was examined using a step-wise linear regression model. Correlation coefficients were negative in April and positive in June at all the stations. The relationships were confirmed by an analysis of regression equations. The regression equations also included coefficients for May and June which, however, were not statistically significant. Yield variation, described by regression equations of the dependence of oats yield on Sielianinov’s hydrothermal coefficient value was accounted for from 19 (Siedlce, Biała Podlaska) to 50% (Ostrołeka).

The atmospheric circulation patterns during dry periods in Lithuania

Rimkus E., Kažys J., Valiukas D., Stankunavičius G.

Oceanologia

2014

No. 56 (2)

223--239

This paper reveals the atmospheric circulation patterns during dry periods in Lithuania.~The research covers the period from 1961 to 2010. Atmospheric circulation features were analysed using the Hess and Brezowski classification of macro-circulation forms, NAO and AO indices, a 500 hPa geopotential height field and the Tibaldi-Molteni blocking index. Different phases of the dry period (developing, persisting and attenuation) were evaluated individually. Also, the regional differences of dry period formation were investigated. In general dry periods are determined by a decrease in zonal and an increase in meridional circulation forms as well as the atmospheric blocking process over the Baltic region longitudinal belt 0-20 days prior to the start of the dry period. An especially strong shift from general circulation patterns are observed during the developing phase of a dry period. Drought persistence in the Baltic region is almost always predetermined by strong anticyclonic circulation. Most drought development stages are associated with negative NAO/AO phases.