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Influence of climate change on the ice conditions of the Curonian Lagoon

100%

Jakimavicius D., Sarauskiene D., Kriauciuniene J.

Oceanologia

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2020

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tom 62

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nr 2

2

Regional climate scenarios and their applications

100%

Liszewska M., Osuch M.

Geographia Polonica

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1998

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tom 71

3

Artificial neural networks use for rainfall-runoff erosivity factor estimation

72%

Licznar P.

Electronic Journal of Polish Agricultural Universities. Series Environmental Development

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2005

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tom 08

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nr 1

Proposed by Wischmeier and Smith rainfall-runoff erosivity factor (R-factor) is usually recognized as a proper tool for regional climatic condition description in respect to soil erosion by water. It is also a basic input to simple and widespread soil erosion prediction models like USLE and RUSLE. However its calculation on the base of original precipitation records is a very laborious operation and is completely impossible for many locations without a precise precipitation data. The aim of the research was to develop a new simple method of annual R-factor values estimation on the base of very general precipitation data. Examined was the possibility of implementing artificial neural networks for annual R-factor values estimation on the base of the sole summer period and annual precipitation totals. The research was conducted with the use of database containing calculated summer period and annual rainfall-runoff erosivity factor values from 138 stations in Germany. As a result of the study 3 radial basis function networks (RBF) of two to five hidden layer neurons and 2 multilayer perceptrons networks (MLP) with one and two hidden layers were developed. Obtained correlation coefficients of observed versus predicted R-factor values were higher then the coefficients reported previously for the simple linear regression models. The study results suggested the possibility of neural networks technology introduction for R-factor values estimation on the base of precipitation totals instead of simple statistical regional relationships.

4

Reasons and consequences of climate changes in Belarus

72%

Loginov V. F.

Acta Agrophysica

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2000

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tom 26

Analysis of temperature measurements in the Polesye and the republic in general revealed the presence of two warmings during the period of observations (~120 years). The warming of the 1930's is of radiation origin and relates to the atmospheric purification from volcanic powder. The heating took place in summer. Modem warming is that of winter type. Its origin is related to the increase of greenhouse gases content in the atmosphere. Changes in precipitation taking place for of many years are of great complexity. In the south part of the republic during the postwar period the amount of precipitation decreased by about 100 mm when compared to the preceding half-century. In the north Belarus a rise of precipitation for the past two decades is observed. The amelioration of southern areas of Belarus and the adjacent territories resulted in temperature variation in southern part of our state by 0.3-0.4 °C, precipitation by 10-35 mm in summer. Temperature and precipitation variation patterns differ in the first and second part of summer.Analysis of the range of daily temperature course, as well as temperature maxima and minima for big towns revealed anthropogenic "signal" that must stressed be while assessing variations in daily course ranges. Interpretation of the features of temperature variability in space and time in towns and suburbs was presented.

5

Quality assessment of atmospheric surface fields over the Baltic Sea from an ensemble of regional climate model simulations with respect to ocean dynamics

58%

Meier H. E. M., Hoglund A., Doscher R., Andersson H., Loptien U., Kjellstrom E.

Oceanologia

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2011

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tom 53

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nr (1-TI)

Climate model results for the Baltic Sea region from an ensemble of eight simulations using the Rossby Centre Atmosphere model version 3 (RCA3) driven with lateral boundary data from global climate models (GCMs) are compared with results from a downscaled ERA40 simulation and gridded observations from 1980 –2006. The results showed that data from RCA3 scenario simulations should not be used as forcing for Baltic Sea models in climate change impact studies because biases of the control climate significantly affect the simulated changes of future projections. For instance, biases of the sea ice cover in RCA3 in the present climate affect the sensitivity of the model’s response to changing climate due to the ice-albedo feedback. From the large ensemble of available RCA3 scenario simulations two GCMs with good performance in downscaling experiments during the control period 1980–2006 were selected. In this study, only the quality of atmospheric surface fields over the Baltic Sea was chosen as a selection criterion. For the greenhouse gas emission scenario A1B two transient simulations for 1961 –2100 driven by these two GCMs were performed using the regional, fully coupled atmosphere-ice-ocean model RCAO. It was shown that RCAO has the potential to improve the results in downscaling experiments driven by GCMs considerably, because sea surface temperatures and sea ice concentrations are calculated more realistically with RCAO than when RCA3 has been forced with surface boundary data from GCMs. For instance, the seasonal 2 m air temperature cycle is closer to observations in RCAO than in RCA3 downscaling simulations. However, the parameterizations of air-sea fluxes in RCAO need to be improved.

6

Relationship between groundwater depth and pattern of net primary production in oasis-desert ecotone

58%

Wu F.-J., Yu Z.-L., Wei X.-P., Deng J. M., Li T., Zhao C.-M., Wang G.-X.

Polish Journal of Ecology

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2010

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tom 58

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nr 4

Pattern of plant biomass and net primary production was investigated in two localities (Minqin and Linze) of oasis-desert ecotone (ODE) in Northwest China, in order to recognize the spatial and temporal variability of vegetation under same regional climate with different groundwater depth. The average depth to groundwater was over 14.02 m at Minqin -- marked further as DG (deep groundwater) and about 4.96 m at Linze -- marked further as SG (shallow groundwater). We have measured plant biomass and Netprimary productivity (NPP) across species, threetimes per year for three consecutive years, in sixplots along Minqin and Linze oasis-desert ecotone(further marked as DG and SG ODE), respectively.Our results showed that DG and SGODEs had different growth responses to differentgroundwater depths. DG ODE exhibited higherinter-annual variation in annual NPP (rangedfrom 0.18 to 9.30 g m⁻²) than did SG ODE (rangedfrom 0.42 to 17.99 g m⁻²). Decrease of groundwaterdepth had apparently altered the seasonalityof productivity in DG ODE systems, where precipitationin summer maintained plant growth,while ODE with high groundwater depth tendedto have higher spring NPP in SG ODE. Spatialand temporal heterogeneity of NPP at the scaleof our measurements was significantly greater inDG ODE than in SG ODE. SG ODE tended tosupport higher NPP than did DG ODE. In addition,the groundwater depth strongly influenced spatial and temporal heterogeneity of NPP in thedesert ecosystems. Clearly, the desert ecosystemwith higher groundwater depth is more stable andmore resistant to long-term drought or climateshifts in arid regions. These investigations andquantitatively analysis are very significant for theexecution of conservation and restoration in aridecosystems.

Ograniczanie wyników

2 Oceanologia

1 Acta Agrophysica

1 Electronic Journal of Polish Agricultural Universities. Series Environmental Development

1 Geographia Polonica

1 Polish Journal of Ecology

1 Andersson H.

1 Deng J. M.

1 Doscher R.

1 Hoglund A.

1 Jakimavicius D.

1 Kjellstrom E.

1 Kriauciuniene J.

1 Li T.

1 Licznar P.

1 Liszewska M.

1 Loginov V. F.

1 Loptien U.

1 Meier H. E. M.

1 Osuch M.

1 Sarauskiene D.

1 Wang G.-X.

1 Wei X.-P.

1 Wu F.-J.

1 Yu Z.-L.

1 Zhao C.-M.

1 2020

1 2011

1 2010

1 2005