Assessment of spatial distributions of some climate indices in Iraq

Aridity is one of the main factors which distinguish the climate of a region and has significant influence on human activities. This study investigated the spatial distribution of the aridity indices to determine the climate conditions in Iraq over the period (1981-2015), depending on the data of the air temperature and rainfall which obtained from 28 stations distributed through Iraq. The used aridity indices are: Lang, Erinc, Emberger, UNEP, De Martonne and Thornthwaite. The spatial distribution was determined using inverse distance weighting (IDW) interpolated method. The results of aridity indices analysis shows that the hyper-arid, arid, and semi-arid categories are predominant with almost (91%) to (100%) of the country’s area. Dry sub-humid, moist sub-humid and humid categories occupies less than (10%) with most of indices at stations of (Arbil, Sulaymaniyah, and Salahaddin). To evaluate the seasonal spatial distributions, De Martonne was utilized. During winter, the climate types ranged from semi-arid to very-humid, while at spring season from arid to humid. Autumn season dominated by arid at (97%) of study area. The summer season was the driest compared with the other seasons. The change point for aridity indices was detected by using the cumulative sum charts (CUSUMs), it is found for the most stations in (1997). Consequently, the spatial distribution for the aridity indices were analyzed through two periods (1981-1997 and 1998-2015), this analysis showed that the arid and hyper-arid areas were increased in the second period compared with the first period with obvious extension toward the north of Iraq.

Contribution to the study of climate change in Serbia using continentality, oceanity, and aridity indices

The aim of the study is to present some specific climatic conditions on the territory of the Republic of Serbia based on the analysis of four climate indices, which can help in understanding contemporary climate changes. Temperature and precipitation data from 31 meteorological stations for the period 1951–2010 were used. The relative homogeneity of the data series was done using the MASH v3.02 method. The indices used are: Johansson Continentality Index, Kerner Oceanity Index, De Martonne Aridity Index, and Pinna Combinative Index. Geospatial analysis of the distribution of the values of the four mentioned indices was done using the QGIS package 2.8.1. The results of the research show that the continentality effect is present in most of Serbia, while oceanity is observed locally, mainly in the western and southwestern parts of the country. The further analysis showed that there is no dry and semi–dry Mediterranean climate in Serbia. Considering that it is dry in the warmest part of the year (July–September), when the need for water is increased, which is clearly shown by the Walter climate diagram, as well as the fact that an increase in temperature and a decrease in precipitation during the vegetation period were observed in the second 30–year period (1981–2010), it can be concluded that in Serbia there is a tendency towards arid climate. The results presented in this paper can help decision makers to plan certain climate change adaptation measures

Changes in the forest ecosystems in areas impacted by aridization in south-western Romania

BACKGROUND: In the past few decades, global climate change has accentuated the intensification of aridization in South-Western Romania, with direct and indirect consequences on the quality of forest ecosystems. In addition to qualitative deterioration, the quantitative changes brought about by intensive anthropic deforestation have created the conditions for a decline in the size of forest areas on vast tracts of land. The paper aims to analyze the qualitative and quantitative changes in the forest ecosystems in South-Western Romania, changes due to the synergic context of the global climate changes and the anthropic pressures of the past three decades. In order to capture the evolution of aridization in the study area, specific aridization indexes have been calculated, such as the De Martonne index and the UNEP aridity index. 1990 and 2011 satellite images have been used in order to quantify the qualitative changes. RESULTS: The results obtained indicated that, in the past two decades, the quality of the biomass declined as a result of the increase in the climatic aridity conditions (De Martonne si UNEP aridity index, indicating in the last decades, annual values under 15 mm/°C, and under 0.5 mm/mm, that means that the values situated under these thresholds, describe arid and semi-arid climate conditions). Also, the uncontrolled logging across vast surfaces caused the loss of forest ecosystems by 7% in the overall study area, during the last three decades. CONCLUSIONS: The severe effects of aridization meant, first of all, a significant decline in the quality of the ecosystem services supplied by forests. In the absence of viable actions to correct the present situation, the extremely undesirable consequences of an ecological and social nature will arise in the near future

Long Term Spatio-temporal Variations of Seasonal and Decadal Aridity in India

A comprehensive analysis of climate data (1958-2018) is carried out at the national scale in India to assess spatiotemporal variation in aridity. The aridity is analyzed using UNEP (United Nations Environment Programme) Aridity Index (AI), which is the ratio between Precipitation (P) and Potential Evapotranspiration (PET). Freely available Terra-Climate database, P and PET variables, offered an unprecedented opportunity for monitoring variations in AI and aridity index anomalies (AIA) at interseasonal and inter-decadal basis. The study also assesses longer term patterns of P and AI anomalies with vegetation anomalies. The results indicate that significant clustered areas with maximum dryness are located at west-central part of India, the state of Maharashtra. Overall, there is a gradual increase in the extent of arid zone during 60-year period and spatially maximum extent of percentage change in aridity area is observed. The change patterns of AI in India are largely driven by the changing patterns of precipitation. The maximum impact of decline in precipitation on AIA was observed during Kharif season frequently, for every 4-5 years during 1972-1992. The pattern repeated in the last few recent years (2013- 2018), the decline in precipitation resulted increased aridity. The study also reveals that the availability and usage of irrigation sources have increased from 2014 to 2018. Thus, despite of less precipitation positive vegetation has been resulted in this period. The findings are important to understand the impacts of climate change on land use pattern, and land and water resource management

Towards a New Agriculture for the Climate Change Era in West Asia, Iran

28 páginas. El libro tiene 486 páginas.Climate change means a change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods. It will potentially lead to such eventualities as drought and famine, which some of the CWANA countries have already experienced. The capacity of national governments and communities to mitigate disasters will be limited in the short to medium term, rendering them still vulnerable to the adversities of climate change. Climate change is a global issue with regional implications. Many multilateral environmental agreements address these issues, and some countries of the region have ratified some such agreements (CWANA, 2009). Effects of climate change on land use refers to both how land use might be altered by climate change and what land management strategies would mitigate the negative effects of climate change (Dale, 1997). Asia is the most populous continent, population in 2002 was reported to be about 3,902 million, of which almost 61% is rural and 38.5% lives within 100 km of the coast (Duedall & Maul, 2005). Asia is divided into seven subregions, namely North Asia, Central Asia, West Asia, Tibetan Plateau, East Asia, South Asia and South-East Asia.Peer reviewe

Climate Change Effects on Temperate Grassland and Its Implication for Forage Production: A Case Study from Northern Germany

The effects of climate change on agricultural ecosystems are increasing, and droughts affect many regions. Drought has substantial ecological, social, and economic consequences for the sustainability of agricultural land. Many regions of the northern hemisphere have not experienced a high frequency of meteorological droughts in the past. For understanding the implications of climate change on grassland, analysis of the long-term climate data provides key information relevant for improved grassland management strategies. Using weather data and grassland production data from a long-term permanent grassland site, our aims were (i) to detect the most important drought periods that affected the region and (ii) to assess whether climate changes and variability significantly affected forage production in the last decade. For this purpose, long-term daily weather data (1961–2019) and the standardized precipitation index (SPI), De Martonne index (IDM), water deficit (WD), dryness index (DI), yield anomaly index (YAI), and annual yield loss index (YL) were used to provide a scientific estimation. The results show that, despite a positive trend in DI and a negative trend in WD and precipitation, the time-series trends of precipitation, WD, and DI indices for 1961–2019 were not significant. Extreme dry conditions were also identified with SPI values less than −2. The measured annual forage yield (2007–2018) harvested in a four-cut silage system (with and without organic N-fertilization) showed a strong correlation with WD (R = 0.64; p < 0. 05). The main yield losses were indicated for the years 2008 and 2018. The results of this study could provide a perspective for drought monitoring, as well as drought warning, in grassland in northwest Europe

Land Sensitivity Analysis of Degradation using MEDALUS model: Case Study of Deliblato Sands, Serbia

This paper studies the assessment of sensitivity to land degradation of Deliblato sands (the northern part of Serbia), as a special nature reserve. Sandy soils of Deliblato sands are highly sensitive to degradation (given their fragility), while the system of land use is regulated according to the law, consisting of three zones under protection. Based on the MEDALUS approach and the characteristics of the study area, four main factors were considered for evaluation: soil, climate, vegetation and management. Several indicators affecting the quality of each factor were identified. Each indicator was quantified according to its quality and given a weighting of between 1.0 and 2.0. ArcGIS 9 was utilized to analyze and prepare the layers of quality maps, using the geometric mean to integrate the individual indicator map. In turn, the geometric mean of all four quality indices was used to generate sensitivity of land degradation status map. Results showed that 56.26% of the area is classified as critical; 43.18% as fragile; 0.55% as potentially affected and 0.01% as not affected by degradation. The values of vegetation quality index, expressed as coverage, diversity of vegetation functions and management policy during the protection regime are clearly represented through correlation coefficient (0.87 and 0.47)