scholarly journals ANALYSIS OF TREND AND VARIABILITY OF SUMMER SEASON VISIBILITY AND TEMPERATURE IN SAHEL ZONE OF NIGERIA

2020 ◽  
Vol 4 (3) ◽  
pp. 489-495
Author(s):  
Mukhtar Balarabe ◽  
Bello Saadu
Keyword(s):  
Meteorological Data ◽  
Negative Relationship ◽  
Negative Temperature ◽  
Summer Season ◽  
Climate Data ◽  
The Past ◽  
Increasing Trend ◽  
Relationship Of ◽  
Threat To Life

The variation of climate in the past on different time scale in Nigeria has generated a lot of concern and is still posing a threat to life and properties. Meteorologist and climatologist in Nigeria are working hard to address this problem. This study assessed the recent trend and variability of summer season`s visibility and temperature for Sahel zone of Nigeria. The long-term (1988-2017) summer seasons meteorological data derived from National Oceanic Atmospheric Agency-National Climate Data Centre (NOAA-NCDC) were used. A significant decreasing trend in visibility and increasing trend in temperature were detected during the entire period of study. The overall averages were 14.71 ± 4.17 km and 24.54 ± 4.19  respectively. The trends were found more significance in the last ten years. The Decades` means are 19.38± 3.05, 13.76 ± 2.09, 10.98 ± 1.28 km  and 20.60 ± 4.72◦C, 25.78 ± 2.54 ◦C and 27.25 ± 0.79  ◦C for the first, second and third decades respectively. Standardize anomaly chart revealed that over the period of study, positive visibility anomaly correspond to negative temperature anomaly and vice visa. Their correlation at p< 0.05 significant level showed a negative relationship of 0.54 over the thirty years period. However, decade analysis showed a positive correlation of 0.47 and negative correlations of 0.61 and 0.74 for the first, second and third decades respectively. These suggest that summer season of the recent decades are dustier than the previous ones and that, summer season of the recent decades become hotter than the previous decades

scholarly journals Impact of climate change and human activity on the runoff in the upper reaches of the Shiyang River, Northwest China

2014 ◽  
Author(s):  
Peng Li ◽  
Jianhua Xu ◽  
Zhongsheng Chen ◽  
Benfu Zhao
Keyword(s):  
Climate Change ◽  
Human Activity ◽  
Climatic Factors ◽  
Meteorological Data ◽  
Northwest China ◽  
Potential Evaporation ◽  
The Past ◽  
Shiyang River Basin ◽  
Runoff Change ◽  
Increasing Trend

Based on the hydrological and meteorological data of the upper reaches of Shiyang River basin in Northwest China from 1960 to 2009, this paper analyzed the change in runoff and its related climatic factors, and estimated the contribution of climate change and human activity to runoff change by using the moving T test, cumulative analysis of anomalies and multiple regression analysis. The results showed that temperature revealed a significant increasing trend, and potential evaporation capacity decreased significantly, while precipitation increased insignificantly in the past recent 50 years. Although there were three mutations in 1975, 1990 and 2002 respectively, runoff presented a slight decreasing trend in the whole period. The contributions of climate change and human activity to runoff change during the period of 1976-2009 were 45% and 55% respectively.

Anthropogenic and Natural Contributions to the Lengthening of the Summer Season in the Northern Hemisphere

2018 ◽  
Vol 31 (17) ◽  
pp. 6803-6819 ◽  
Author(s):  
Bo-Joung Park ◽  
Yeon-Hee Kim ◽  
Seung-Ki Min ◽  
Eun-Pa Lim
Keyword(s):  
Northern Hemisphere ◽  
Coupled Model ◽  
Atlantic Multidecadal Oscillation ◽  
Summer Season ◽  
Season Length ◽  
The Past ◽  
External Forcings ◽  
Regional Trends ◽  
Intercomparison Project

Observed long-term variations in summer season timing and length in the Northern Hemisphere (NH) continents and their subregions were analyzed using temperature-based indices. The climatological mean showed coastal–inland contrast; summer starts and ends earlier inland than in coastal areas because of differences in heat capacity. Observations for the past 60 years (1953–2012) show lengthening of the summer season with earlier summer onset and delayed summer withdrawal across the NH. The summer onset advance contributed more to the observed increase in summer season length in many regions than the delay of summer withdrawal. To understand anthropogenic and natural contributions to the observed change, summer season trends from phase 5 of the Coupled Model Intercomparison Project (CMIP5) multimodel simulations forced with the observed external forcings [anthropogenic plus natural forcing (ALL), natural forcing only (NAT), and greenhouse gas forcing only (GHG)] were analyzed. ALL and GHG simulations were found to reproduce the overall observed global and regional lengthening trends, but NAT had negligible trends, which implies that increased greenhouse gases were the main cause of the observed changes. However, ALL runs tend to underestimate the observed trend of summer onset and overestimate that of withdrawal, the causes of which remain to be determined. Possible contributions of multidecadal variabilities, such as Pacific decadal oscillation and Atlantic multidecadal oscillation, to the observed regional trends in summer season length were also assessed. The results suggest that multidecadal variability can explain a moderate portion (about ±10%) of the observed trends in summer season length, mainly over the high latitudes.

scholarly journals Meteorological controls on glacier mass balance: empirical relations suggested by measurements on glacier de Sarennes, France

1997 ◽  
Vol 43 (143) ◽  
pp. 131-137 ◽  
Author(s):  
C. Vincent ◽  
M. Vallon
Keyword(s):  
Mass Balance ◽  
Time Scale ◽  
Meteorological Data ◽  
Empirical Relation ◽  
Glacier Mass Balance ◽  
Glacier Surface ◽  
Surface Conditions ◽  
The Past ◽  
Empirical Relations

AbstractGlacial mass-balance reconstruction for a long-term time-scale requires knowledge of the relation between climate change and mass-balance fluctuations. A large number of mass-balance reconstructions since the beginning of the century are based on statistical relations between monthly meteorological data and mass balance. The question examined in this paper is: are these relationships reliable enough for long-term time-scale extrapolation? From the glacier de Sarennes long mass-balance observations series, we were surprised to discover large discrepancies between relations resulting from different time periods. The importance of the albedo in relation to ablation and mass balance is highlighted, and it is shown that it is impossible to ignore glacier-surface conditions in establishing the empirical relation between mass-balance fluctuations and climatic variation; to omit this parameter leads to incorrect results for mass-balance reconstruction in the past based on meteorological data.

Relationship of Temperature and Light Ring Formation at Subarctic Treeline and Implications for Climate Reconstruction

1993 ◽  
Vol 39 (2) ◽  
pp. 256-262 ◽  
Author(s):  
David K. Yamaguchi ◽  
Louise Filion ◽  
Melissa Savage
Keyword(s):  
Black Spruce ◽  
Threshold Temperature ◽  
Climate Data ◽  
New Approach ◽  
The Past ◽  
Summer Temperatures ◽  
Instrumental Records ◽  
Relationship Of ◽  
Visual Assessments ◽  
Light Ring

AbstractDuring the past 8 centuries, light rings (LRs) have occasionally formed in black spruce (Picea mariana) at treeline near Bush Lake, northern Quebec (L. Filion, S. Payette, L. Gauthier, and Y. Boutin, 1986, Quaternary Research 26, 272-279; A. Delwaide, L. Filion, and S. Fayette, 1991, Canadian Journal of Forest Research 21, 1828-1832). New analyses of climate data compiled during the period of overlapping tree-ring and instrumental records show that years of LR formation at Bush Lake have unusually cool May, June, August, and September temperatures. The analyses also show that August-September temperatures strongly correlate with May-July temperatures. Thus, late spring and entire growing-season temperatures influence LR formation at subarctic treeline. LRs formed in at least 5% of the trees at Bush Lake when May-September mean temperatures at Inukjuak fell below 4.2°C and August-September mean temperatures fell below 6.7°C. These threshold temperature/LR relationships can be used to infer limiting summer temperatures during the period preceding instrumental records. For example, the LR record suggests that May-September temperatures at northern Quebec treeline dropped below 4.2°C in A.D. 1601 after a major volcanic eruption of unknown source. Visual assessments of LR occurrence provide a new approach for extracting quantitative paleoclimatic information from tree rings.

scholarly journals LONG-TERM MONITORING OF THE EUROPEAN ROLLER (CORACIAS GARRULUS) IN UKRAINE: IS CLIMATE BEHIND THE CHANGES?

2021 ◽  
Author(s):  
Tatiana Shupova ◽  
Volodymyr Tytar
Keyword(s):  
Spatially Explicit ◽  
Climate Data ◽  
Time Intervals ◽  
Coracias Garrulus ◽  
The Past ◽  
Historical Times ◽  
Long Term Monitoring ◽  
European Roller ◽  
Term Monitoring

Since the 1980s there has been a long-term decline in numbers and contraction of range in Europe, including Ukraine. Our specific goals were to reconstruct the climatically suitable range of the species in Ukraine before the 1980s, gain better knowledge on its requirements, compare the past and current suitable areas, infer the regional and environmental variables that best explain its occurrence, and quantify the overall range change in the country. For these purposes we created a database consisting of 347 records of the roller made ever in Ukraine. We employed a species distribution modeling (SDM) approach to hindcast changes in the suitable range of the roller during historical times across Ukraine and to derive spatially explicit predictions of climatic suitability for the species under current climate. SDMs were created for three time intervals (before 1980, 1985-2009, 2010-2021) using corresponding climate data extracted from the TerraClim database. SDMs show a decline of suitable for rollers areas in the country from 85 to 46%. Several factors, including land cover and use, human population density and climate, that could have contributed to the decline of the species in Ukraine were considered. We suggest climate change and its speed (velocity) have been responsible for shaping the contemporary home range of the European roller.

The Spread and Persistence of Māturīdi Kalām and Underlying Dynamics

2009 ◽  
Vol 13 (1) ◽  
pp. 59-92
Author(s):  
Philipp Bruckmayr
Keyword(s):  
South Asia ◽  
19Th Century ◽  
Legal Tradition ◽  
The Past ◽  
Theological Schools ◽  
State Of Affairs ◽  
Relationship Of ◽  
The 19Th Century ◽  
The Relationship

AbstractThe paper is concerned with a long-term perspective on the position of Māturīdi kalām within (mostly) Hanafi Muslim societies from Timurid times to the 19th century. Whereas outright conflict between legal and theological schools was mainly a thing of the past during the time in question with Ash'arism, already fully embraced also by Hanafi constituencies within the ahl al-sunna wa l-jamā'a, a preference for Māturīdi views on specific issues persisted among the majority of Hanafi kalām scholars from Bosnia to South Asia. This state of affairs will be highlighted through recourse to madrasa curricula and theological literature from the era and areas as diverse as Turkey and Southeast Asia. Additionally, it seeks to draw attention to the mechanisms behind the spread and long-term persistence of the school throughout large parts of a Muslim world seemingly dominated by Ash'arism in the sphere of scholastic theology. In this regard, the prevalence of Transoxanian legal tradition within Hanafism and its linkages to Māturīdism, as well as the relationship of Naqshbandi Sufism to the school will be discussed.

scholarly journals Investigating the Complexity of Runoff Series in the Yangtze River Using Sample Entropy

10.29007/ttss ◽  
2018 ◽  
Author(s):  
Yuankun Wang ◽  
Dong Wang ◽  
Xiaorui Shi
Keyword(s):  
Yangtze River ◽  
Dynamic Change ◽  
Negative Relationship ◽  
Sliding Window ◽  
Sample Entropy ◽  
Spatial Difference ◽  
The Yangtze River ◽  
Runoff Series ◽  
Increasing Trend

Based on sample entropy, we investigated spatial distribution and dynamic change of runoff series complexity with the long-term daily runoff series of main stem in the Yangtze River. The results showed that, complexity of the runoff series show an obvious spatial difference, and an increasing trend from upstream to downstream in the Yangtze River. There are negative relationship between average of runoff sliding window and the corresponding sample entropy, and their peak-to-valley value shows the well corresponding relationships. Complexity of the runoff series at Yichang and Datong stations show a continuous increasing trend, while that of Hankou station an increasing trend after 2000. It could provide scientific reference for understanding of runoff series dynamic evolution in the Yangtze River.

scholarly journals Diabetic Cardiac Autonomic Dysfunction and Its Relationship with Duration of Diabetes

2016 ◽  
Vol 11 (1) ◽  
pp. 1-5
Author(s):  
Phurpa ◽  
Sultana Ferdousi
Keyword(s):  
Type 2 Diabetes ◽  
Autonomic Dysfunction ◽  
Negative Relationship ◽  
Duration Of Diabetes ◽  
Cardiac Autonomic Dysfunction ◽  
Male Patients ◽  
Relationship Of ◽  
The Relationship

Background: Duration of diabetes may have an important influence on cardiac autonomic dysfunction in type 2 diabetes mellitus.Objective: To assess the relationship of cardiac autonomic dysfunction in type 2 diabetes mellitus(T2DM) with the duration of diabetes.Methods: This crosssectional study was carried out from January to December 2015 on 54 long-term T2DM male patients aged 45 to 55 years, selected from the Endocrinology OPD of BSMMU, Dhaka. Thirty age matched recently diagnosed male T2DM patients(RT2DM) were control. Cardiac autonomic function was assessed by Heart Rate Variability(HRV). HRV measures were obtained by RMS multi channel polyrite-D. For statistical analysis, unpaired t-test and Pearson’s correlation coefficient test were used.Results: Mean RR, SDNN, and HF nu were significantly lower (p < 0.001) whereas, mean HR, LF nu and LF/HF were significantly (p < 0.001) higher in LT2DM than those of RT2DM. SDNN, RMSSD and variance showed significant (p < 0.001) negative correlation with the duration of diabetes.Conclusions: Duration of diabetes had strong negative relationship with the diabetic cardiac autonomic dysfunction.Bangladesh Soc Physiol. 2016, June; 11(1): 1-5

1,2,4-Triazole: A Privileged Scaffold for the Development of Potent Antifungal Agents - A Brief Review

2020 ◽  
Vol 20 (24) ◽  
pp. 2235-2258
Author(s):  
Christophe Tratrat
Keyword(s):  
Antifungal Agents ◽  
Term Therapy ◽  
Invasive Infection ◽  
Drug Resistant ◽  
The Past ◽  
Chemistry Research ◽  
Privileged Scaffold ◽  
Long Term Therapy ◽  
Relationship Of

Over the past decades, a tremendous rise in invasive fungal infection diseases attributed to the yeast Candida albicans in immunocompromised individuals poses a seriously challenging issue. Another concern is the emergence of multi-drug resistant pathogens to the existing medicines due to their overuse and misuse. It was recently reported that 25-55% of the mortality rate is caused by invasive infection. Despite a large variety of drugs being available to treat invasive candidiasis, only two of them contain a 1,2,4-triazole core, namely Fluconazole and itraconazole, which are efficient in treating infection induced by fungal Candida species. Moreover, long-term therapy associated with azole medications has led to an increase in azole resistance as well as a high risk of toxicity. Despite numerous outstanding achievements in antifungal drug discovery, development of novel, safer and potent antifungal agents while overcoming the resistance problem associated with the current drugs is becoming the main focus of medicinal chemists. Therefore, this review outlines the breakthroughs in medicinal chemistry research regarding 1,2,4- triazole-based derivatives as potential antifungal agents in the past decade. In addition, the structureactivity relationship of these compounds is also discussed.

scholarly journals Life prospects of the unemployed: invariant and variable components in the prism of the last decade (2009-2018)

2018 ◽  
Vol 55 ◽  
pp. 02028
Author(s):  
Irina Ralnikova ◽  
Yana Smirnova
Keyword(s):  
Cultural Context ◽  
Men And Women ◽  
The Past ◽  
Life Planning ◽  
The Future ◽  
Relationship Of ◽  
The Unemployed ◽  
The Relationship

The article discusses the results of a comparison of the content and structure of life prospects of the unemployed men and women surveyed in 2009 and 2018. The study showed the specificity of the relationship of the socio-cultural context of a person’s life and his/her life prospects. The invariant and variable components of the life prospects of the unemployed are revealed. Over the past ten years, a pessimistic and contradictory view of the future, a temporary orientation to a negative past and a fatalistic present, a weak eventful and targeted saturation of the future, lack of long-term planning, the existence of a conflict of time settings are invariant, which, in many respects, is a reflection of the difficulty of experiencing the absence of work. Along with the stable characteristics, transformations of the content of life planning in a situation of lack of work are revealed. The assessment of the life prospects of the unemployed, who tend to see the future as swift and useful, turned out to be varied.

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