Spatial and Temporal Analysis of Maximum and Minimum Temperature Trends in Northern Sudan during (1990-2019)

The study addresses an urgent and globally significant issue of climate change by focusing on the detailed spatial and temporal analysis of temperature trends in Northern Sudan. It fills a critical research gap by providing localized data over a substantial period (1990-2019), which could help in understanding the nuanced impacts of climate change in Sahel regions like Northern Sudan. In addition, the comprehensive coverage of both spatial and temporal dimensions, supported by a substantial dataset from five meteorological stations, provides a thorough understanding of the subject area. The utilization of robust statistical methods (Mann-Kendall test and Sen’s slope analysis) for analyzing temperature trends adds scientific rigor and credibility to the findings. Our results reveal a consistently increasing trend in maximum temperatures across most stations, particularly during the hot season (AMJ). However, the wet season (JAS) shows high maximum temperatures but no significant trend. Moreover, significant increasing trends in minimum temperatures were observed in all stations except Abu Hamed, where the trend, although increasing, did not reach statistical significance during the hot and cold seasons, and the coldest temperatures were observed during the cold season. These findings underscore the complex temperature dynamics in Northern Sudan and highlight the need for continued monitoring and adaptive measures in response to ongoing climate changes in the region.

Recent Climatic Effects on Seasonal Rice Yields in Bangladesh： A Statistical Overview

Expecting that agricultural yield is highly dependent on climatic conditions, particularly water availability and suitable temperature, an agroclimatic study was carried out on rice crops during three different seasons in four regions of Bangladesh. Data on climate （surface air temperature and precipitation） and seasonal rice production were examined for the period 1986-2006 from 18 rice growth observatories. The relationship between climate and rice production was statistically analyzed by removing long-term trends so that the effects of improved irrigation, which results in a general increase in crop production, may be removed. The analysis involved both single and multiple regressions. The results suggested that, during monsoon and summer, higher temperatures had negative effects on rice production, especially in the northwestern （NW） region. In winter, positive effects were observed throughout Bangladesh. Since the annual mean temperature was positively correlated with those in the three seasons individually, the annual temperature had negative effects on the annual rice production only in the NW region, while it had positive effects in the central and southern regions. With the exception of the NW region, it was basically dry, excessive rainfall both in summer and monsoon yielded floods and reduced rice yield. In winter, more rainfall showed positive effects on crop production only in the central region, which was least irrigated. These findings suggested that accelerated atmospheric warming would result in serious damage to crops during summer and monsoon. Reliable prediction of future crop production will rely on the temperature and rainfall trends in individual seasons.

Theoretical Analysis of Cold Storage Devices in a CO2 Transcritical/Subcritical Supermarket Refrigeration Plant

This paper proposes a theoretical study of a cold storage system in a CO2 （carbon dioxide） MT （medium temperature） plant for supermarkets application. The aim of this plant strategy is that in the daily hours the storage can export heat form the refrigerant outcoming the gas cooler/condenser whereas during the nightly hours it can be maintained cooled by this latter before its incoming into the evaporator. Besides, the storage can be used for reducing the energy peak consumption, permitting to size the plant on a lower energy target, and it can influence the choice of the optimisation logic of the plant controller, in this work a model for a MT CO2 transcritical/subcritical cycle, able to manage the transient due to the changes of loads and external conditions, is proposed to take into account the evolution with time in a fixed time step. A parametrical analysis has been conduced for understanding the optimal design of the plant. A seasonal analysis is considered too, for understanding the cold storage benefits in different periods of year.

史前人类在青藏高原的定居与动物资源利用

The transition of human societies from high mobility to sedentary lifestyles had a profound impact on subsistence,technology,and the origin of civilization.Sedentism was influenced by various factors such as climate change,population growth,resource pressure,and technological innovation.The Tibetan Plateau,due to its alpine and hypoxic conditions,is an ideal region to study human adaptation to extreme environments.However,the prehistoric process of sedentism on the Tibetan Plateau is unclear and the chronological sequence and driving mechanism of sedentism on the Tibetan Plateau are still controversial.Previous studies have focused on the diffusion of agriculture from low to high elevation areas,with little attention given to the role of animal resources in sedentism.Seasonality analysis using animal remains is crucial in determining whether a site was occupied year-round.To establish the seasonal calendar of animal resource utilization,it is recommended to create a database of skeletal morphology,whole genome,and proteome of contemporary Tibetan Plateau fauna to aid in the identification of animal remains from archaeological sites.Thus,intricate web of human-animal-environment relationship and the role of animal resources in human sedentism on the Tibetan Plateau can then be evaluated.

Estimation of aerosol optical depth in relation to meteorological parameters over eastern and western routes of China Pakistan economic corridor

This study finds out seasonal and monthly variations in Aerosol Optical Depth(AOD)over eastern and western routes of China Pakistan Economic Corridor(CPEC)and the relationship between AOD and meteorological parameters(i.e.,temperature,rainfall and wind speed).The Moderate Resolution Imaging Spectroradiometer(MODIS)and Multi-angle Imaging Spectroradiometer(MISR)data was used from the terra satellite for the period of 2000-2016.This study aims to overtake the conventional view of the purpose of using the satellite datasets.This study takes on to the concept that validated satellite data sets rather should be used for the analysis instead of just validation specifically for our study region.Hence,after comparing MODIS AOD with MISR AOD,only MISR AOD dataset is used for further analysis.The results show a decreasing trend of AOD in summer season,a positive relationship between temperature and AOD during winter and spring seasons whereas a positive relationship between wind speed and AOD in winter and spring seasons over eastern and western routes.Periodic analysis of MODIS AOD and MISR AOD depicts May-Aug as the peak period of aerosol concentration over central Pakistan.The inter-annual analysis shows the aerosol trend remained higher during summer season however rainfall shows the washout effect.Eastern route has higher standard deviation and larger values for aerosol prevalence as compared to western route.The trajectory analysis using the HYSPLIT model suggests the bias of air mass trajectory caused deviation in the aerosol trend in the year 2014.

A nonautonomous mat hematical model to assess the impact of algae on the abatement of atmospheric carbon dioxide

The world's oceans have played an important role in sequestering atmospheric carbon dioxide through solubility and the action of algae.Fixation of atmospheric carbon dioxide by photoautotrophic algal cultures has the potential to diminish the release of carbon dioxide into the atmosphere,thereby helping to alleviate the trend toward global warming.This work investigates the role of algae in controlling the level of atmospheric carbon dioxide.Partial Rank Correlation Coefficients(PRCCs)technique is used to address how the concentration of atmospheric carbon dioxide is affected by changes in a specific parameter disregarding the uncertainty over the rest of the model parameters.Parameters related to algal growth are shown to significantly reduce the level of atmospheric CO_(2).Further,we explore the dynamics of nonautonomous system by incorporating the seasonal variations of sonic ecologically important model parameters.Our nonautonomous system exhibits globally attractive positive periodic solution,and also the appearance of double periodic solution is observed.Moreover,by letting the seasonally forced parameters as almost periodic functions of time,we show almost periodic behavior of the system.Our findings suggest that the policy makers should focus on continuous addition of nutrients in the ocean to accelerate the algal growth thereby reducing the level of carbon dioxide in the atmosphere.