scholarly journals Winter warming detection using temperature and precipitation anomalies in arid and semi-arid areas

Author(s):  
Negar Siabi ◽  
Mohammad Mousavi Baygi ◽  
Seyed Majid Hasheminia ◽  
Mohammad Bannayan

Abstract Extreme winter warming can affect many aspects of environmental and human related activities. It can be disastrous, especially in arid regions. However, no specific research has been carried out on detecting winter warming in Iran. To address this research gap, this study was performed to investigate winter warming in the arid and semi-arid areas located in northeastern Iran. For this purpose, anomalies of minimum and maximum daily temperature, average daily temperature, mean daily temperature range and mean daily precipitation were studied on monthly, seasonal, annual and decadal scales. Along with this, the trend in the data was analyzed using the Mann–Kendall (MK) test. The results showed that since the 1990s there has been a significant increase in temperature positive anomalies at most stations. In addition, the precipitation anomaly mutations occurred later than temperature. In most cases the increase in winter anomalies was higher than the average annual anomalies. As an example, the maximum winter temperature anomaly increased from 0.38 °C in the 1990s to 2.07 °C in the 2000s at Mashhad station. Due to the simultaneous increase in anomalies at most stations, the detected winter warming is more likely to be the result of global warming rather than local synoptic climate.

2018 ◽  
Vol 49 (6) ◽  
Author(s):  
Jawad &et al.

Evaluation of drought patterns in Iraq and determining the most susceptible areas of this phenomenon were analyzed, using the remotely-sensed Drought Severity Index (DSI) through analysis the daily and annual DSI for three zones over Iraq, also have been analyzed DSI time series using run theory to evaluate the characteristics of drought in Iraq. The efficiency of DSI for drought monitoring was examined from compared with Percentage of Precipitation Anomaly (PPA) for three zones (Arid and Semi-Arid, Steppes and Desert), and compared with drought indicators (Evapotranspiration (ET), Potential evapotranspiration (PET) and total annual precipitation (PRE)) for the period 2000-2011, were derived from the Numerical Terradynamic Simulation Group (NTSG). The spatial interpolation techniques in Geographic Information System (GIS) package has been used, to cover the whole extent of country and extracting the zones. Statistical methods were applied to compute the probability of drought events at every zone. The results showed the drier year is 2008, the wetter years are 2001 in Desert zone and 2003 in steppes and Arid and Semi-Arid Zone zones. The results also showed a significant fluctuation in precipitation from the average, especially at Arid and Semi-Arid Zone when compared with other zones. The values of standard deviation of precipitation were compared with precipitation anomalies for each zone, Arid and Semi-Arid is the drier zone in 2007-2008, the wetter zone is also Arid and Semi-Arid in 2002-2003. Using run theory, the drier Zone is Arid and Semi-Arid and the wetter Zone is steppes during study period.


1989 ◽  
Vol 16 (3) ◽  
pp. 219-226
Author(s):  
Saâd Bennis ◽  
Paul-Édouard Brunelle

The predictive snowmelt runoff model (SRM), previously suggested by other authors, is reliable and easy to use. Furthermore, the only parameters required are temperature and precipitation, and density and thickness of the snow pack. The literature available indicates that simulation results with this model are generally satisfactory. However, data on the extent of the snow cover are not always available; this means that the snow pack must be calculated before the SRM can be used. Our purpose herein is to develop a model to evaluate the snowpack, which is to be used in conjunction with the SRM. The SRM was modified in that maximum daily temperature was used instead of the number of degrees-days. The snowmelt and snow cover models were calibrated and tested along the drainage basin of the Eaton River, a tributary of the Saint-François River in the province of Quebec. Key words: snowmelt, prediction, flooding. [Journal translation]


2010 ◽  
Vol 36 (1) ◽  
pp. 89-98 ◽  
Author(s):  
Abderazak Djabeur ◽  
Meriem Kaid-Harche ◽  
Daniel Côme ◽  
Françoise Corbineau

2017 ◽  
Vol 192 ◽  
pp. 209-220 ◽  
Author(s):  
Wei Mao ◽  
Jinzhong Yang ◽  
Yan Zhu ◽  
Ming Ye ◽  
Jingwei Wu
Keyword(s):  

1998 ◽  
Vol 22 ◽  
pp. 238-240
Author(s):  
L. R. Ndlovu ◽  
L. Hove

Browse species are important food resources in semi-arid areas, especially during the dry season when the nutritive value of grass is at its lowest. However, browse plants often contain secondary plant compounds which limit their nutritive value. Proanthocyanidins (PAs) (also called condensed tannins) and related flavonoids are a common constituent of woody plants in tropical regions (Mangan, 1988). PAs cause a bitter and astringent taste which lowers food palatability and they also lower the digestibility of proteins and carbohydrates (Jacksonet al., 1996). PAs also interfere with current chemical methods that are used for estimating nutritive value of foods (Reed, 1995). Biological assays, especially ,in vitrotechniques, have a potential to reflect better the nutritive value of foods that contain PAs. Thein vitrogas production technique has been found to reliably predict the nutritive value of temperate forages (Makkaret al., 1996). There has been limited research on its efficacy with tropical forages. The experiment reported here was conducted to test the hypothesis that gas production of tropical browse species reflects their content of fibre, protein and/or PAs.


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