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Oceans, Ice &Snow and CO2 Rise, Swing and Seasonal Fluctuation
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作者 Michael D. Nelson David B. Nelson 《International Journal of Geosciences》 2016年第10期1232-1282,共51页
Carbon dioxide rise, swing and spread (seasonal fluctuations) are addressed in this study. Actual CO<sub>2</sub> concentrations were used rather than dry values. The dry values are artificially higher beca... Carbon dioxide rise, swing and spread (seasonal fluctuations) are addressed in this study. Actual CO<sub>2</sub> concentrations were used rather than dry values. The dry values are artificially higher because water vapor must be removed in order for the NDIR instrument to work and is not factored back into the reported numbers. Articles addressing these observations express opinions that are divergent and often conflicting. This investigation resolves many of those inconsistencies. The data were obtained from many measuring stations at various latitudes since 1972 and then graphical compared to changes in sea temperatures, fossil fuel emissions, humidity, and seasonal ice and snow changes. In analyzing the data, various parameters were addressed including: variability, R squared curve values, correlations between curves, residence times, absorption percentages, and Troposphere effects. Mass balance calculations were also made to corroborate viability. The CO<sub>2</sub> “rise” over a 33-year period from a slight ocean temperature increase (0.7°F) contributed 2.3 percent of the total rise while fossil fuel emissions contributed 1.5 percent. The overwhelming majority (60 ppmv, 96%+) was caused by other factors including ocean and land biology as well potential errors in fundamental hypotheses. With respect to “spread” (seasonal CO<sub>2</sub> fluctuations) at the Polar Circles, graphical analysis with high correlations supported by mass balance calculations confirm that ice and snow are the primary cause and explain why the concentrations are the highest at these cold locations. The global variations in “swing” remain uncertain. 展开更多
关键词 CO2 RISE seasonal fluctuation Ice & Snow Fossil Fuel Emissions Biology
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Temperature and Precipitation Fluctuation of Madinah-Al-Munawara, Kingdom of Saudi Arabia (1959-2011) 被引量:1
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作者 Saifullah Khan Yasser Alghafari 《Atmospheric and Climate Sciences》 2016年第3期402-414,共14页
The work discusses the temperature and precipitation fluctuation of Madinah-Al-Munawara, Saudi Arabia for a time period of 1959-2011. This is a city in the Hejaz region of western Saudi Arabia, the capital of Al Madin... The work discusses the temperature and precipitation fluctuation of Madinah-Al-Munawara, Saudi Arabia for a time period of 1959-2011. This is a city in the Hejaz region of western Saudi Arabia, the capital of Al Madinah Province and important religious place. For many years now, Royal Kingdom of Saudi Arabia is active on national as well as international levels to adopt a more suitable policy for the study of climate changes and reviews it periodically as per country economic desires. The main sectors that affect the temperature and precipitation fluctuations in Saudi Arabia are surface water, coastal management, overgrazing, forestry, livestock, drought, desertification, industrialization, landuse change, tourism, and aridity etc. The paper analyzes the temperature and precipitation fluctuations of Madinah-Al-Munawara in terms of general climatology, climate fluctuation/variation, seasonal distribution and extreme weather events. The mean monthly temperature of the city recorded during 1959-2011 is 28°C having mean maximum temperature of 34°C and mean minimum of 21°C. The mean monthly temperature of the city shows an increase of 1.7&deg;C having 1.2&deg;C increase in maximum temperature and decrease of -1.9&deg;C in minimum temperature. Generally, there is a rise and fall in the temperature condition and shows irregular pattern throughout the period. The total precipitation of the city is 36 millimeters;having a decrease of -0.3 millimeters but in general the trend of precipitation at Madinah-Al-Munawara shows an increasing trend throughout the period. April and November are the wettest, while June, August, September and October are the hottest months of the city. The area is characterized by two main seasons that is winter (5 months) and summer (7 months), which can further be sub-divided into four rainy seasons namely winter, post-winter, summer, and post-summer seasons. 展开更多
关键词 CLIMATOLOGY fluctuation seasonal fluctuation Hajjand Ummrah SUMMER WINTER Wettest Hottest
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Occurrence and Damage Regularity of Spodoptera litura in Broccoli
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作者 Weiming Liu Enguo Wang Yenan Liu 《Plant Diseases and Pests》 CAS 2021年第4期5-8,共4页
[Objective] The paper was to explore the occurrence and damage regularity of Spodoptera litura in broccoli,and to reveal the annual movement regularity and seasonal fluctuation regularity of S.litura population.[Metho... [Objective] The paper was to explore the occurrence and damage regularity of Spodoptera litura in broccoli,and to reveal the annual movement regularity and seasonal fluctuation regularity of S.litura population.[Method] The monitoring data of sexual attractants at fixed points for 11 consecutive years were summarized and analyzed.[Result] The large occurrence frequency of S.litura in Taizhou was 36.4%;the annual movement showed a downward-opening parabolic form,and the movement trajectory was N =-18.416 t^(2)+182.51 t +179.71,t ={1,2,3,…,n}(n =11;r =0.691 7*).The seasonal fluctuation showed a trend of peak oscillation attenuation curve,and the total moth quantity gradually decreased from sowing to heading stage.The functional model of average daily quantity was m=0.000 2 d^(2)-0.067 5 d+6.797 3,d={1,2,3,…,n}(n =186,r=0.955 2**).Air temperature was the main external factor affecting the seasonal variation of quantity,and there was a significant correlation be-tween the number of ten-day moth trapping quantity and ten-day average temperature:M =0.243 T^(2)-6.935 1 T +46.681(n =108,r =0.560 2**)or M=2.734 4 T-35.446(n=108,r=0.500 3**).Therefore,the moth quantity in the field increased with the increase of ten-day average temperature,and the period from July to September with high temperature and less rainfall was the peak occurrence period of S.litura.[Conclusion] These models can be used to improve the prediction and early warning levels of S.litura in broccoli,and has good guiding significance for decision-making and prevention. 展开更多
关键词 BROCCOLI Spodoptera litura seasonal fluctuation Impact factor
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Probability of a zoonotic spillover with seasonal variation
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作者 Aadrita Nandi Linda J.S.Allen 《Infectious Disease Modelling》 2021年第1期514-531,共18页
Zoonotic infectious diseases are spread from animals to humans.It is estimated that over 60%of human infectious diseases are zoonotic and 75%of them are emerging zoonoses.The majority of emerging zoonotic infectious d... Zoonotic infectious diseases are spread from animals to humans.It is estimated that over 60%of human infectious diseases are zoonotic and 75%of them are emerging zoonoses.The majority of emerging zoonotic infectious diseases are caused by viruses including avian influenza,rabies,Ebola,coronaviruses and hantaviruses.Spillover of infection from animals to humans depends on a complex transmission pathway,which is influenced by epidemiological and environmental processes.In this investigation,the focus is on direct transmission between animals and humans and the effects of seasonal variations on the transmission and recovery rates.Fluctuations in transmission and recovery,besides being influenced by physiological processes and behaviors of pathogen and host,are driven by seasonal variations in temperature,humidity or rainfall.A new time-nonhomogeneous stochastic process is formulated for infectious disease spread from animals to humans when transmission and recovery rates are time-periodic.A branching process approximation is applied near the disease-free state to predict the probability of the first spillover event from animals to humans.This probability is a periodic function of the time when infection is introduced into the animal population.It is shown that the highest risk of a spillover depends on a combination of animal to human transmission,animal to animal transmission and animal recovery.The results are applied to a stochastic model for avian influenza with spillover from domestic poultry to humans. 展开更多
关键词 Branching process Markov chain seasonal fluctuations SPILLOVER ZOONOSES
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Non-stationary water-level fluctuation in China's Poyang Lake and its interactions with Yangtze River 被引量:18
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作者 DAI Xue WAN Rongrong YANG Guishan 《Journal of Geographical Sciences》 SCIE CSCD 2015年第3期274-288,共15页
Seasonal water-level fluctuations (WLF) play a dominate role in lacustrine ecosys- tems. River-lake interaction is a direct factor in changes of seasonal lake WLF, especially for those lakes naturally connected to u... Seasonal water-level fluctuations (WLF) play a dominate role in lacustrine ecosys- tems. River-lake interaction is a direct factor in changes of seasonal lake WLF, especially for those lakes naturally connected to upstream and downstream rivers. During the past decade, the modification of WLF in the Poyang Lake (the largest freshwater lake in China) has caused intensified flood and irrigation crises, reduced water availability, compromised water quality and extensive degradation of the lake ecosystem. There has been a conjecture as to whether the modification was caused by its interactions with Yangtze River. In this study, we investi- gated the variations of seasonal WLF in China's Poyang Lake by comparing the water levels during the four distinct seasons (the dry season, the rising season, the flood season, and the retreating season) before and after 2003 when the Three Gorge Dam operated. The Water Surface Slope (WSS) was used as a representative parameter to measure the changes in river-lake interaction and its impacts on seasonal WLF. The results showed that the magni- tude of seasonal WLF has changed considerably since 2003; the seasonal WLF of the Poy- ang Lake have been significantly altered by the fact that the water levels both rise and retreat earlier in the season and lowered water levels in general. The fluctuations of river-lake in- teractions, in particular the changes during the retreating season, are mainly responsible for these variations in magnitude of seasonal WLF. This study demonstrates that WSS is a rep- resentative parameter to denote river-lake interactions, and the results indicate that more emphasis should be placed on the decrease of the Poyang Lake caused by the lowered water levels of the Yangtze River, especially in the retreating season. 展开更多
关键词 seasonal water-level fluctuations in lakes slope of water surface river-lake interactions Poyang Lake
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Pollutant removal from municipal wastewater employing baffled subsurface flow and integrated surface flow-floating treatment wetlands 被引量:7
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作者 Tanveer Saeed Abdullah Al-Muyeed +2 位作者 Rumana Afrin Habibur Rahman Guangzhi Sun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第4期726-736,共11页
This article reports pollutant removal performances of baffled subsurface flow, and integrated surface flow-floating treatment wetland units, when arranged in series for the treatment of municipal wastewater in Bangla... This article reports pollutant removal performances of baffled subsurface flow, and integrated surface flow-floating treatment wetland units, when arranged in series for the treatment of municipal wastewater in Bangladesh. The wetland units (of the hybrid system) included organic, inorganic media, and were planted with nineteen types of macrophytes. The wetland train was operated under hydraulic loading fluctuation and seasonal variation. The performance analyses (across the wetland units) illustrated simultaneous denitrification and organics removal rates in the first stage vertical flow wetland, due to organic carbon leaching from the employed organic media. Higher mean organics removal rates (656.0 g COD](m2.day)) did not completely inhibit nitrification in the first stage vertical flow system; such pattern could be linked to effective utilization of the trapped oxygen, as the flow was directed throughout the media by the baffle walls. Second stage horizontal flow wetland showed enhanced biodegradable organics removal, which depleted organic carbon availability for denitrification. The final stage integrated wetland system allowed further nitrogen removal from wastewater, via nutrient uptake by plant roots (along with nitrification), and generation of organic carbon (by the dead macrophytes) to support denitrification. The system achieved higher E. coli mortality through protozoa predation, E. coli oxidation, and destruction by UV radiation. In general, enhanced pollutant removal efflciencies as demonstrated by the structurally modified hybrid wetland system signify the necessity of such modification, when operated under adverse conditions such as: substantial input organics loading, hydraulic loading fluctuation, and seasonal variation. 展开更多
关键词 constructed wetlands loading fluctuation media nitrogen organics seasonal variation
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