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Volume XIV |

Near surface thermal characteristics of alpine steep rockwalls in the Retezat Mountains

Abstract: The characteristics of the near surface thermal regime of two rockwalls with different aspect in the Retezat Mountains were investigated using two miniature thermistors. Three one-year (2012-2013; 2013-2014 and 2014-2015) rock surface temperature time series were available for the north facing rockwall, whereas only two seasons were analyzed for the south facing rockwall. The mean annual rock surface temperature (MARST) values were with 1.5-2°C colder on the northern rockwall compared with the southern steep bedrock face. Due to long daily exposure to sunshine, the south facing rockwall experienced more diurnal freeze-thaw cycles during the cold season compared to the north facing rockwall. Overall, the thermistor with a southern aspect recorded 40 and 55 more freeze-thaw cycles than the northern one. A greater number of effective freeze-thaw cycles were measured on the south facing rockwall. The maximum daily amplitude on the southern rockwall is three times higher than on the north-facing location (39.1°C compared to 13.6°C). Based on our findings it seems that the MARST values recorded on the shaded face of the steep bedrock suggest a quite likely absence of permafrost, whereas the MARST values at TPR indicate a quite certain absence of permafrost.

Volume XIV |

The North Atlantic Oscillation Influence on the Climate and Flow Variability of the Lower Danube Valley, between the Towns of Olteniţa and Călărăşi, Romania

Abstract: As previous international research has identified, the large-scale NAO atmospheric circulation pattern dominates climate variability in the northern hemisphere. In this study we investigate the impact of the North Atlantic Oscillation (NAO) index on annual/winter precipitation and river flow regimes for a sector of the lower Danube Valley. An important goal was to test the relation between the NAO pattern and the occurrences of extreme events. We assume that precipitation variability and river flow are harder to assimilate into a modified anthropogenic environment as the situation of the Danube in the study area. During the communist regime, this valley sector was transformed from a wetland environment into a farming area. Understanding NAO – rainfall and NAO – river flow relationships were based on monthly data in the time period between January 1977 and December 2010 for the NAO index, the river basin average precipitation over the Danube and the Danube river flow measured at Oltenita and at Calarasi Stations. Results showed that the large inter-annual variability in the precipitation regime and flows of the Danube is largely modulated by the NAO phenomenon. The four-time series in study are weak stationary, which means that the natural events vary moderately along a constant mean and the extreme events do not have the power to propagate, vanishing after few time steps.

Volume XIV |

Evaluation of rainfall extremes. Northeast and West coast regions of India as case study

Abstract: The response of climate change is the increase in the frequency and intensity of extreme weather events. An attempt has been made to study the trends in heavy rainfall amount and the highest rainfall value in 24 hours over Northeast region (NER) and West coast region (WCR) of India with the period ranging from 1901-2009. A standard statistical analysis concludes that the majority of the stations in NER and WCR indicates increasing trend in annual and monsoon rainfalls. Further, the increasing trends in heavy rainfall were investigated and the associated synoptic conditions were identified. The study reveals that the increase in heavy rainfall over the WCR can be attributed to the synoptic systems namely monsoon trough, cyclonic circulation, depressions and lows.

Volume XIV |

Assessing flood inundation extent and landscape vulnerability to flood using geospatial technology: A study of Malda district of West Bengal, India

Abstract: Assessment of flood risk zonation and landscape vulnerability to flood are fundamental aspects in flood risk management. Landsat 8 Operational Land Imager (OLI) and ASTER DEM data were used to assess landscape vulnerability to flood inundation and flood risk in Malda district of West Bengal state, India. Flood inundation map was prepared on the basis of water and non-water pixels on images (before and during the flood event). Flood risk map was prepared using equal interval of separation based on elevation and inundated flooded area. Flood inundation map was overlaid on the pre-monsoon land use/land cover map to produce landscape vulnerability to flood. The results revealed that 19% area of the district was flooded during monsoon flood event in 2014 and the agricultural area was most affected land use, sharing 62% of the total flood affected area, followed by river bed (21%), built up (7%) and vegetation (5%). The flood risk map of the district shows that temporary river islands, sand banks along the Ganga river course lie in low flood plain and were considered under high risk zone. The flood plain alongside minor stream drainage in southern, north-western and in between them comes under medium flood risk zones. Flood risk is low in areas which are away from the rivers. Non flooded areas were identified in high lands of eastern region of the district. Landscape vulnerability map shows that the blocks located along the Ganga river namely Kaliachak I, Kaliachak II, Kaliachak III, Manikchak, Ratua I were highly vulnerable to flood. The study suggests that efforts should be made to remove the sediments for increasing the depth of river. Spurs and bed bars should be constructed to avoid great loss of prime agricultural land, property and lives of people.

Volume XIV |

Territorial patterns of socio-economic development in the Romanian Danube valley

Abstract: The territorial patterns of socio-economic development in the Romanian Danube Valley (micro-scale, LAU2) are identified in this paper by using the complex index of development (INDEV). The paper presents the computation of secondary indexes reflecting the main aspects of socio-economic development (dwellings, public utilities infrastructure, health, employment, demography, education and local economy). The territorial distribution of the secondary indexes and the complex index of development values emphasized a difference between the rural and urban administrative units, the rural areas shaping the low and very low pattern of socio-economic development and the towns and municipals representing the average pattern of socio-economic development. The complex index of territorial disparities, computed by the variant of the relative distances ranking method (using as baseline the national average value of each statistical indicator selected), shows the overwhelming predominance of socio-economic development pattern below the Romanian average.