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An Updated Estimation of Radiative Forcing due to CO_2 and Its Effect on Global Surface Temperature Change
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作者 张华 张若玉 石广玉 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第4期1017-1024,共8页
New estimations of radiative forcing due to CO2 were calculated using updated concentration data of CO2 and a high-resolution radiative transfer model. The stratospheric adjusted radiative forcing (ARF) due to CO2 f... New estimations of radiative forcing due to CO2 were calculated using updated concentration data of CO2 and a high-resolution radiative transfer model. The stratospheric adjusted radiative forcing (ARF) due to CO2 from the year 1750 to the updated year of 2010 was found to have increased to 1.95 W m-2, which was 17% larger than that of the IPCC's 4th Assessment Report because of the rapid increase in CO2 concentrations since 2005. A new formula is proposed to accurately describe the relationship between the ARF of CO2 and its concentration. Furthermore, according to the relationship between the ARF and surface temperature change, possible changes in equilibrium surface temperature were estimated under the scenarios that the concentration of CO2 increases to 1.5, 2, 2.5, 3, 3.5 and 4 times that of the concentration in the year 2008. The result was values of +2.2℃, +3.8℃, +5.1℃, +6.2℃, +7.1℃ and +8.0℃ respectively, based on a middle-level climate sensitivity parameter of 0.8 K (W m 3)-1. Non-equilibrium surface temperature changes over the next 500 years were also calculated under two kinds of emission scenarios (pulsed and sustained emissions) as a comparison, according to the Absolute Global Temperature change Potential (AGTP) of CO2. Results showed that CO2 will likely continue to contribute to global warming if no emission controls are imposed, and the effect on the Earth-atmosphere system will be difficult to restore to its original level. 展开更多
关键词 co2 radiative forcing surface temperature change global Temperature change Potential
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Erratum to “Autonomous Changes in the Concentration of Water Vapor Drive Climate Change” [Atmospheric and Climate Sciences 10 (2020) 443-508]
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作者 William Van Brunt 《Atmospheric and Climate Sciences》 2021年第3期535-546,共12页
<p> A. <span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Changes </span></span></span><... <p> A. <span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Changes </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">in</span></span></span><span><span><span style="font-family:" color:black;"=""><span style="font-family:Verdana;"> average global temperature are not driven by changes in the concentration of carbon dioxide;</span></span></span></span> </p> <p> <span style="font-family:Verdana;">B. </span><span style="font-family:Verdana;">Instead, autonomous changes in the concentration of water vapor, </span><span style="font-family:Verdana;">Δ</span><span style="font-family:Verdana;">TPW, </span><span color:black;"=""><span style="font-family:Verdana;">drive changes in water vapor heating, thus, </span><span style="background:#C00000;font-family:Verdana;">changes in</span><span style="font-family:Verdana;"> the average global temperature, </span></span><span style="font-family:Verdana;">Δ</span><span style="font-family:Verdana;"><i>T</i></span><span style="font-family:Verdana;"><sub>Avg</sub></span><span color:black;"=""><span style="font-family:Verdana;">, </span><span style="background:#C00000;font-family:Verdana;">in deg. Celsius are calculated</span><span style="font-family:Verdana;"> in accordance with this principle,</span></span> </p> <p style="text-align:center;margin-left:10pt;"> <span><span><span style="font-family:" color:black;"=""><span style="font-family:Verdana;"></span><img src="Edit_6e770969-a7c9-4192-a6ad-03de906a4d65.bmp" alt="" /><br /> </span></span></span> </p> <p align="center" style="margin-left:10.0pt;text-align:center;"> <span><span><span style="font-family:;" "=""><span></span></span></span><span><span><span style="font-family:" color:black;"=""></span></span></span></span> </p> <p> <span><span><span style="font-family:" color:black;background:#c00000;"=""><span style="font-family:Verdana;">measured in kg<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"=""><span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">·</span></span>m</span><sup><span style="font-family:Verdana;"><span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#ffffff;"="">-</span>2</span></sup><span style="font-family:Verdana;">,</span></span></span></span><span><span><span style="font-family:" color:black;"=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">the average accuracy of which is ±0.14%, when compared to the variable annual, 1880 </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:" color:black;"=""><span style="font-family:Verdana;"> 2019, </span><span style="background:#C00000;font-family:Verdana;">average global </span><span style="font-family:Verdana;">temperature record;</span></span></span></span> </p> 展开更多
关键词 Carbon Dioxide Climate change Water Vapor global Warming DRIVER Average global Temperature change in concentration Water Vapor Water Vapor Heating
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Effects of the Adjustment of Energy Structure on 24-h Average of NO_2 Concentration in Different Regions of Urumqi City in Winter
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作者 Nuorsaolie Jiang Wei 《Meteorological and Environmental Research》 CAS 2013年第5期26-29,共4页
[ Objective] The study aimed to discuss the effects of the adjustment of energy structure on daily average concentration of NO2 in different regions of Urumqi city in winter. [ Method] The changes of daily average con... [ Objective] The study aimed to discuss the effects of the adjustment of energy structure on daily average concentration of NO2 in different regions of Urumqi city in winter. [ Method] The changes of daily average concentration of NO2 in different areas of Urumqi City from January to February ( NO2 pollution was most serious) before and after the implementation of the project "changing coal to gas" were analyzed. [ Result] After the implementation of the project, daily average concentration of NO2 in different areas of Urumqi City was increased due to the rapid increase of ve- hicle quantity, but there were certain differences in the increase among various regions. From south to north, daily average concentration of NO2 in winter was decreased gradually, that is, daily average concentration of NO2 was the highest in the south area, while in the north area, it didn't change significantly before and after the implementation of the project, but it was still high. Therefore, the local government should pay more attention to pollution NO2 during environmental management process. [ Conclusion] The research could provide scientific references for the control of atmospheric pollution in future. 展开更多
关键词 Changing coal to gas Vehicle exhaust Air pollution Spatial distribution NO2 concentration China
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Autonomous Changes in the Concentration of Water Vapor Drive Climate Change
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作者 William A. Van Brunt 《Atmospheric and Climate Sciences》 2020年第4期443-508,共66页
When compared to the average annual global temperature record from 1880, no published climate model posited on the assumption that the increasing concentration of atmospheric carbon dioxide is the driver of climate ch... When compared to the average annual global temperature record from 1880, no published climate model posited on the assumption that the increasing concentration of atmospheric carbon dioxide is the driver of climate change can accurately replicate the significant variability in the annual temperature record. Therefore, new principles of atmospheric physics are developed for determining changes in the average annual global temperature based on changes in the average atmospheric concentration of water vapor. These new principles prove that: 1) Changes in average global temperature are not driven by changes in the concentration of carbon dioxide;2) Instead, autonomous changes in the concentration of water vapor, <span style="white-space:nowrap;">Δ</span>TPW, drive changes in water vapor heating, thus, the average global temperature, <span style="white-space:nowrap;">Δ</span>T<sub>Avg</sub>, in accordance with this principle, <span style="white-space:normal;"><span style="white-space:nowrap;">Δ</span>T</span><span style="white-space:normal;"><sub>Avg</sub>=0.4<span style="white-space:normal;"><span style="white-space:nowrap;">Δ</span>TPW </span></span>the average accuracy of which is ±0.14%, when compared to the variable annual, 1880-2019, temperature record;3) Changes in the concentration of water vapor and changes in water vapor heating are not a feedback response to changes in the concentration of CO<sub>2</sub>;4) Rather, increases in water vapor heating and increases in the concentration of water vapor drive each other in an autonomous positive feedback loop;5) This feedback loop can be brought to a halt if the average global rate of precipitation can be brought into balance with the average global rate of evaporation and maintained there;and, 6) The recent increases in average global temperature can be reversed, if average global precipitation can be increased sufficiently to slightly exceed the average rate of evaporation. 展开更多
关键词 Carbon Dioxide Climate change Water Vapor global Warming DRIVER Average global Temperature change in concentration Water Vapor Water Vapor Heating
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水限制环境CO_(2)与施氮交互作用对春小麦水分利用效率的影响 被引量:2
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作者 李裕 齐月 +3 位作者 王小恒 朱青青 岳平 张强 《干旱地区农业研究》 CSCD 北大核心 2023年第1期228-234,共7页
在模拟大气CO_(2)浓度升高环境条件下,进行了不同施氮处理对春小麦水分利用效率的影响试验,探索水资源限制地区提高春小麦水分利用率及其产量的途径。结果表明,CO_(2)浓度升高与施氮交互作用对小麦产量水分利用率有显著影响。在CO_(2)... 在模拟大气CO_(2)浓度升高环境条件下,进行了不同施氮处理对春小麦水分利用效率的影响试验,探索水资源限制地区提高春小麦水分利用率及其产量的途径。结果表明,CO_(2)浓度升高与施氮交互作用对小麦产量水分利用率有显著影响。在CO_(2)浓度升高90μmol·mol^(-1)环境条件下,135 kg·hm^(-2)和315 kg·hm^(-2)施氮处理春小麦产量的水分利用率与对照相比分别下降了5.8%和15.1%;225 kg·hm^(-2)和405 kg·hm^(-2)施氮处理春小麦产量的水分利用率与对照相比分别增加了9.3%和8.9%;225 kg·hm^(-2)和405 kg·hm^(-2)施氮处理使春小麦生物量水分利用率与对照相比分别提高了10.4%和10.8%;而135 kg·hm^(-2)和315 kg·hm^(-2)施氮处理造成春小麦生物量水分利用率不同程度地下降。90μmol·mol^(-1) CO_(2)浓度升高与施氮处理导致春小麦千粒重水分利用率下降,其中135 kg·hm^(-2)和315 kg·hm^(-2)施氮处理使春小麦千粒重水分利用率较对照分别下降了13.9%和21.2%。在CO_(2)浓度升高180μmol·mol^(-1)环境条件下,施氮处理对春小麦产量水分利用率的影响不显著。尽管施氮处理提高了春小麦生物量水分利用率,却导致春小麦千粒重水分利用率不同程度降低。综上可知,在未来大气CO_(2)浓度升高背景下,可以根据CO_(2)浓度升高幅度,从调控氮肥投入量途径入手,提高春小麦水分利用效率及其产量。 展开更多
关键词 气候变化 水限制地区 春小麦 水分利用效率 co_(2)浓度升高 施氮量
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施氮和增温对鄱阳湖灰化薹草(Carex cinerascens Kukenth.)湿地秋草生长期氧化亚氮排放的影响 被引量:1
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作者 程俊翔 徐力刚 +2 位作者 樊龙凤 陈曦 游海林 《湖泊科学》 EI CAS CSCD 北大核心 2024年第4期1152-1162,共11页
湿地是地球上十分重要的氮库,而且对大气氮沉降增加、气候变暖等全球变化响应非常敏感。目前关于湿地氧化亚氮(N_(2)O)的研究还存在较大的区域不均衡性,湿地N_(2)O排放对全球变化的响应也具有很大的不确定性。因此,本研究通过在鄱阳湖... 湿地是地球上十分重要的氮库,而且对大气氮沉降增加、气候变暖等全球变化响应非常敏感。目前关于湿地氧化亚氮(N_(2)O)的研究还存在较大的区域不均衡性,湿地N_(2)O排放对全球变化的响应也具有很大的不确定性。因此,本研究通过在鄱阳湖灰化薹草(Carex cinerascens Kukenth.)湿地开展N_(2)O通量原位监测及全球变化模拟实验,以揭示鄱阳湖灰化薹草湿地N_(2)O排放变化特征及其对施氮和增温的响应关系。结果表明,鄱阳湖灰化薹草湿地总体上是N_(2)O弱源,平均N_(2)O通量为(5.77±1.45)μg/(m^(2)·h)。施氮对鄱阳湖灰化薹草湿地N_(2)O通量有显著影响,相对于不施氮,施氮可显著提升2.7倍的N_(2)O排放通量。增温及其与施氮的交互作用对N_(2)O通量的影响不显著。鄱阳湖灰化薹草湿地N_(2)O排放过程主要由湿地植物调节,而与空气温度、土壤温度、土壤水分等非生物因素无显著相关关系。研究结果有利于深入认识全球变化与湖泊湿地N_(2)O排放的互馈作用,并为评估全球变化背景下湖泊湿地N_(2)O收支平衡提供重要支撑;未来还需要加强多因子交互作用研究并开展长期连续监测,从而为阐明湿地氮循环对全球变化的响应机制和构建气候预测模型提供验证数据和理论依据。 展开更多
关键词 鄱阳湖湿地 温室气体 N_(2)O 全球变化 氮沉降 气候变暖
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CO_(2)浓度升高及增温下谷子土壤酶活性及其温度敏感性 被引量:1
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作者 梁蒙 路冰冰 +4 位作者 吴阳 王雪松 郑粉莉 刘国彬 薛萐 《中国生态农业学报(中英文)》 CAS CSCD 北大核心 2023年第1期79-89,共11页
研究作物重要生长阶段土壤酶活性及其温度敏感性对CO_(2)浓度升高及增温的响应,对于评价气候变化对作物生产的影响以及评估土壤生态系统的功能稳定性具有重要意义。利用人工气候室模拟不同水分(充分供水和轻度干旱)、CO_(2)浓度升高(由... 研究作物重要生长阶段土壤酶活性及其温度敏感性对CO_(2)浓度升高及增温的响应,对于评价气候变化对作物生产的影响以及评估土壤生态系统的功能稳定性具有重要意义。利用人工气候室模拟不同水分(充分供水和轻度干旱)、CO_(2)浓度升高(由400μmol·mol^(-1)升高至700μmol·mol^(-1))和增温(由22℃升高至26℃)条件,以3个因素交互作用下盆栽谷子(Setaria italica)土壤为研究对象,分析了谷子灌浆期土壤中β-葡糖苷酶(βG)、β-N-乙酰葡糖苷酶(NAG)、纤维素酶(CBH)和β-木糖苷酶(βX)活性的温度敏感性。结果表明,对照(CK)在充分供水条件下土壤βG、NAG、CBH和βX的酶活性随着培养温度增加呈先升高后降低的趋势,在25℃时酶活性最高。在最适温度下(25℃),与CK相比,CO_(2)浓度升高使谷子灌浆期土壤βG酶活性显著降低,而对土壤NAG、CBH、βX酶活性的抑制作用较小;CO_(2)浓度升高和增温的交互作用在不同水分条件下表现不同,具体表现为轻度干旱条件下酶活性受到抑制,而充分供水时无显著差异。此外,CO_(2)浓度和温度显著影响谷子灌浆期土壤酶活性的温度敏感性(Q_(10))CO_(2)浓度升高使土壤胞外酶活性的Q_(10)显著增大,而增温使Q_(10)相对减小。在充分供水条件下,增温抵消了CO_(2)浓度升高对酶活性Q_(10)的影响,二者的交互作用对Q_(10)无显著影响。然而,在轻度干旱条件下,CO_(2)浓度升高和增温对Q_(10)影响显著,即CO_(2)浓度、温度及水分三者对Q_(10)的交互作用显著。同时,CO_(2)浓度与水分对Q_(10)有显著的交互作用,但与仅CO_(2)浓度升高以及3个因素交互作用的影响无明显差异。冗余分析显示,除CO_(2)浓度和温度外,Q_(10)还受到微生物量、土壤养分等环境因子的影响。本研究表明CO_(2)浓度、温度和水分以及三者之间的交互作用对土壤酶活性及其温度敏感性的影响复杂,特别是CO_(2)浓度升高抑制了土壤酶的温度敏感性,减弱了土壤碳氮循环相关酶的代谢功能及其稳定性,进而影响土壤生态系统的功能稳定性。 展开更多
关键词 气候变化 co_(2)浓度升高 增温 土壤酶活性 温度敏感性
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1979-2022年北极海冰变化及影响因素分析
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作者 邓丽静 金波文 +3 位作者 全梦媛 王爱梅 范文静 王慧 《海洋信息技术与应用》 2024年第1期8-16,共9页
海冰是海洋-大气交互系统的重要组成部分,是全球气候变化的指示器。深入分析海冰演变规律,探索全球气候变化与海冰范围之间的关联,对应对和减缓全球气候变化具有重要的理论意义。本文以北极海冰为研究对象,深入分析了1979-2022年北极海... 海冰是海洋-大气交互系统的重要组成部分,是全球气候变化的指示器。深入分析海冰演变规律,探索全球气候变化与海冰范围之间的关联,对应对和减缓全球气候变化具有重要的理论意义。本文以北极海冰为研究对象,深入分析了1979-2022年北极海冰范围的季节、年际和年代际变化特征,并构建向量自回归模型(Vector AutoRegressive Model,VAR)检验全球平均气温、大气CO_(2)浓度与北极海冰范围之间的因果关系,并分析影响程度。结果表明:(1)北极海冰范围季节变化特征明显,一般在3月达到最大,9月达到最小,这主要与太阳辐射的年变化周期相关;(2)1979-2022年,北极海冰范围总体呈减小趋势,年变化量为5.3万km^(2);(3)北极海冰范围在年代际尺度上逐渐减小,2000-2009年,北极海冰范围较上一个十年减小最多(减少67万km^(2));(4)全球平均气温和大气CO_(2)浓度均对北极海冰范围变化造成了显著影响;(5)全球平均气温和大气CO_(2)浓度与北极海冰范围均有显著负相关关系,相关系数分别为-0.92和-0.95。 展开更多
关键词 北极海冰范围 co_(2)浓度 平均气温 全球气候变化
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Comparison of airsea fluxes of CO_(2) in the Southern Ocean and the western Arctic Ocean 被引量:10
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作者 GAOZhongyong YANGXulin WANGWeiqiang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2004年第4期647-653,共7页
The data were collected during Chinese Arctic and Antarctic Expeditions in the western Arctic Ocean and themarginal sea ice zone (MSIZ) of the Southern Ocean, respectively in the boreal summer from July to September o... The data were collected during Chinese Arctic and Antarctic Expeditions in the western Arctic Ocean and themarginal sea ice zone (MSIZ) of the Southern Ocean, respectively in the boreal summer from July to September of1999 and in the austral summer from December of 1999 to January of 2000. The concentrations of CO2 in surfacewater of the survey regions would mostly present lower than those in the atmosphere. A significant biologicaldriving force could also been observed in summer waters in both of the above oceans. Air to sea CO2 fluxes were alsocalculated to compare oceanic uptake capacity of CO2 in both oceans with the world oceans using Liss, Wanninkhof,and Jacobss methods. The averaged CO2 fluxes of air to sea in the western Arctic Ocean or in the MSIZ of theSouthern Ocean doubled that in the world oceans. 展开更多
关键词 co2 airsea exchange global change Southern Ocean western Arctic Ocean
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温度升高和CO_(2)浓度增加对冬小麦田土壤氮磷含量的影响
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作者 苑嘉承 陈粲 虞凯浩 《中国农业气象》 CSCD 北大核心 2023年第8期675-684,共10页
采用T-FACE(Temperature-free air carbon dioxide enrichment)试验平台,设置田间常规温度和CO_(2)浓度(CK)、田间常规温度和增加CO_(2)浓度至575μmol·L^(-1)(C)、升高温度(高于大气温度2℃)和田间常规CO_(2)浓度(T)以及升高温度... 采用T-FACE(Temperature-free air carbon dioxide enrichment)试验平台,设置田间常规温度和CO_(2)浓度(CK)、田间常规温度和增加CO_(2)浓度至575μmol·L^(-1)(C)、升高温度(高于大气温度2℃)和田间常规CO_(2)浓度(T)以及升高温度(高于大气温度2℃)和增加CO_(2)浓度至575μmol·L^(-1)(CT)共4个处理,对田间冬小麦进行控制实验。在小麦播种期、越冬期、分蘖期和成熟期分别采集不同层次的土壤样品(耕作层0-14cm、犁底层14-33cm、潴育层33-59cm和潜育层59-80cm),分析大气CO_(2)浓度增加和温度升高后农田土壤N、P含量及其有效性的动态变化,以揭示气候变化对农田土壤中养分含量的时空影响。结果表明:(1)冬小麦在越冬期CO_(2)浓度增加的情况下,常规或升高温度可使潴育层土壤中硝态氮含量出现下降趋势,在越冬期除T处理外,CK、C和CT处理的硝态氮含量在播种期低于耕作层。在越冬期的各处理中,硝态氮含量以CK处理增加最为明显。(2)在增加CO_(2)浓度和升高温度的情况下,耕作层土壤中铵态氮含量在越冬期和分蘖期显著低于田间正常的CO_(2)浓度和温度处理,且在不同土壤层次中未表现出明显的上升或下降的现象;铵态氮含量在小麦整个生长期相对稳定,但CT、C和T三种不同处理条件下,小麦成熟期铵态氮含量明显增加,且温度升高处理下的增加趋势显著(P<0.05);在小麦整个生育期内,C处理下铵态氮表现出先上升后下降的趋势,而CK、CT和T处理则表现出上升—下降—上升的趋势。(3)小麦全生育期内CK处理的速效磷含量明显高于其它处理,且在播种期、越冬期和分蘖期,CK处理与CT和T处理速效磷含量差异显著(P<0.05)。未来气候变化引起的CO_(2)浓度增加和温度升高情况下,应合理施用N、P肥,减少不必要的养分流失。 展开更多
关键词 气候变化 温度升高 co_(2)浓度升高 冬小麦生育期 土壤N、P含量
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Future meteorological drought conditions in southwestern Iran based on the NEX-GDDP climate dataset
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作者 Sakine KOOHI Hadi RAMEZANI ETEDALI 《Journal of Arid Land》 SCIE CSCD 2023年第4期377-392,共16页
Investigation of the climate change effects on drought is required to develop management strategies for minimizing adverse social and economic impacts.Therefore,studying the future meteorological drought conditions at... Investigation of the climate change effects on drought is required to develop management strategies for minimizing adverse social and economic impacts.Therefore,studying the future meteorological drought conditions at a local scale is vital.In this study,we assessed the efficiency of seven downscaled Global Climate Models(GCMs)provided by the NASA Earth Exchange Global Daily Downscaled Projections(NEX-GDDP),and investigated the impacts of climate change on future meteorological drought using Standard Precipitation Index(SPI)in the Karoun River Basin(KRB)of southwestern Iran under two Representative Concentration Pathway(RCP)emission scenarios,i.e.,RCP4.5 and RCP8.5.The results demonstrated that SPI estimated based on the Meteorological Research Institute Coupled Global Climate Model version 3(MRI-CGCM3)is consistent with the one estimated by synoptic stations during the historical period(1990-2005).The root mean square error(RMSE)value is less than 0.75 in 77%of the synoptic stations.GCMs have high uncertainty in most synoptic stations except those located in the plain.Using the average of a few GCMs to improve performance and reduce uncertainty is suggested by the results.The results revealed that with the areas affected by wetness decreasing in the KRB,drought frequency in the North KRB is likely to increase at the end of the 21st century under RCP4.5 and RCP8.5 scenarios.At the seasonal scale,the decreasing trend for SPI in spring,summer,and winter shows a drought tendency in this region.The climate-induced drought hazard can have vast consequences,especially in agriculture and rural livelihoods.Accordingly,an increasing trend in drought during the growing seasons under RCP scenarios is vital for water managers and farmers to adopt strategies to reduce the damages.The results of this study are of great value for formulating sustainable water resources management plans affected by climate change. 展开更多
关键词 climate change meteorological drought global Climate Models(GCMs) Standard Precipitation index(SPI) Representative concentration Pathway(RCP) NASA Earth Exchange global Daily Downscaled Projections(NEX-GDDP) southwestern Iran
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Interactive Effects of Elevated CO_2 and Temperature on Rice Planthopper, Nilaparvata lugens 被引量:2
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作者 SHI Bao-kun HUANG Jian-li +1 位作者 HU Chao-xing HOU Mao-lin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第7期1520-1529,共10页
It is predicted that the current atmospheric CO2 concentration will be doubled and global mean temperature will increase by 1.5-6&#176;C by the end of this century. Although a number of studies have addressed the sep... It is predicted that the current atmospheric CO2 concentration will be doubled and global mean temperature will increase by 1.5-6&#176;C by the end of this century. Although a number of studies have addressed the separate effects of CO2 and temperature on plant-insect interactions, few have concerned with their combined impacts. In the current study, a factorial experiment was carried out to examine the effect of a doubling CO2 concentration and a 3℃ temperature increase on a complete generation of the brown planthopper (Nilaparvata lugens) on rice (Oryza sativa). Both elevated CO2 and temperature increased rice stem height and biomass of stem parts. Leaf chlorophyll content increased under elevated CO2, but only in ambient temperature treatment. Water content of stem parts was reduced under elevated temperature, but only when coupled with elevated CO2. Elevated CO2 alone increased biomass of root and elevated temperature alone enhanced leaf area and reduced ratio of root to stem parts. Brown planthopper (BPH) nymphal development was accelerated, and weight of and honeydew excretion by the F1 adults was reduced under elevated temperature only. Longevity of brachypterous females was affected by a signiifcant interaction between CO2 and temperature. At elevated temperature, CO2 had no effect on female longevity, but at ambient temperature, the females lived shorter under elevated CO2. Female fecundity was higher at elevated than at ambient temperature and higher at elevated CO2 than at ambient CO2. These results indicate that the combined effects of elevated temperature and CO2 may enhance the brown planthopper population size. 展开更多
关键词 climate change elevated co2 global warming Nilaparvata lugens RICE development
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Effects of elevated atmospheric CO2 and nitrogen fertilization on nitrogen cycling in experimental riparian wetlands 被引量:2
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作者 Jun Liu Gloria Appiah-Sefah Theresa Oteng Apreku 《Water Science and Engineering》 EI CAS CSCD 2018年第1期39-45,共7页
Studies on the relationship between plant nitrogen content and soil nitrogen reduction under elevated CO2 conditions and with different nitrogen additions in wetland ecosystems are lacking. This study was meant to ass... Studies on the relationship between plant nitrogen content and soil nitrogen reduction under elevated CO2 conditions and with different nitrogen additions in wetland ecosystems are lacking. This study was meant to assess the effects of elevated CO2 concentrations and inorganic nitrogen additions on soil and plant nitrogen cycling. A cultured riparian wetland, alligator weeds, and two duplicated open top chambers (OTCs) with ambient (380μmol/mol) and elevated (700 μmol/mol) CO2 concentrations at low (4 mg/L) and high (6 mg/L) nitrogen fertilization levels were used. The total plant biomass increased by 30.77% and 31.37% at low and high nitrogen fertilization levels, respectively, under elevated CO2 conditions. Plant nitrogen content decreased by 6.54% and 8.86% at low and high nitrogen fertilization levels, respectively. The coefficient of determination (R2) of soil nitrogen contents ranged from 0.81 to 0.96. Under elevated CO2 conditions, plants utilized the assimilated inorganic nitrogen (from the soil) for growth and other internal physiological transformations, which might explain the reduction in plant nitrogen content. A reduction in soil dissolved inorganic nitrogen (DIN) under elevated CO2 conditions might have also caused the reduction in plant nitrogen content. Reduced plant and soil nitrogen contents are to be expected due to the potential exhaustive use of inorganic nitrogen by soil microorganisms even before it can be made available to the soil and plants. The results from this study provide important information to help policy makers make informed decisions on sustainable management of wetlands. Larger-scale field work is recommended in future research. 展开更多
关键词 Elevated co2 concentration invasive species Plant growth Climate change inorganic nitrogen Nitrogen cycling
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不同气象条件下大气CO_(2)浓度变化特征研究
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作者 张静 赵京波 李爽 《环境科学与管理》 CAS 2023年第3期134-139,共6页
在研究大气CO_(2)浓度变化特征过程中,发现不同气象条件对CO_(2)浓度影响较大,但是在具体分析上数据精度不足,严重影响全局分析水平。针对这一问题,提出不同气象条件下大气CO_(2)浓度变化特征分析。利用监测技术采集大气CO_(2)监测数据... 在研究大气CO_(2)浓度变化特征过程中,发现不同气象条件对CO_(2)浓度影响较大,但是在具体分析上数据精度不足,严重影响全局分析水平。针对这一问题,提出不同气象条件下大气CO_(2)浓度变化特征分析。利用监测技术采集大气CO_(2)监测数据,绘制小时标准差分布图,根据数据分布趋势,采用针对性的处理方式消除异常值,通过聚类方法提取出大气CO_(2)浓度在时间上的分布特点,将其与气象因素相结合,建立回归方程,分析大气CO_(2)浓度空间上的变化特征。实验结果表明:提出的分析方法能够满足精度要求,保证高水平的全局一致性。 展开更多
关键词 气象条件 大气环境 浓度变化 co_(2) 聚类分析
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THE IMPACTS OF GLOBAL CHANGE ON DESERTIFICATION IN CHINA
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作者 Ci Longjun Commission for Integrated Survey of Natural Resources, CAS, Beijing 100101 People’s Republic of China 《Journal of Geographical Sciences》 SCIE CSCD 1997年第3期91-104,共14页
Global change and desertification are the serious environmental problems in the world today and exert great impacts on human existence and social development. Therefore, the United Nations has set up quite a number of... Global change and desertification are the serious environmental problems in the world today and exert great impacts on human existence and social development. Therefore, the United Nations has set up quite a number of relevant organizations to encourage millions upon millions of people to combat this harmful problem. At the same time, since the 1992 UN Conference on Environment and Development (UNCED) in Rio de Janeiro, the UN Convention to Combat Desertification has been signed and this signment of the Convention will powerfully promote the concrete action programs to combat desertification of each affected country and enlarge the exchange and cooperation among the affected countries. According to recent information of UN Organizations, more than 100 countries and their one-fifth world of population are facing the problem of desertification processes and desertification impacts, and are suffering from expansion of desertification. The total areas of arid, semi-arid and dry sub-humid zones cover approximately about 6.5 billion ha, occupying 41 percent of the total land area of the earth. There are 3.6 billion ha of arable land and grazing land under the impact of desertification in the world. From 1984 to 1991, the annual increase of land desertification is 3.4 percent. The harmful results of desertification on human existence in terms of environment, societies and economy are serious and called for great attention from the UN Systems. It is concluded that desertification is the most serious environmental problem in the world and its resulting impact is socially and economically surprising. 展开更多
关键词 DESERTIFICATION global change co 2 concentration greenhouse effect China.
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Some Remarks on the Individual Contribution to Climate Change 被引量:1
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作者 Andreas Oberheitmann 《American Journal of Climate Change》 2013年第3期198-202,共5页
Climate change is one of the most important challenges of the 21st Century. As greenhouse gas concentration of the atmosphere has reached the 400ppm threshold of a 2°C global warming on 9 May 2013 and irreversibl... Climate change is one of the most important challenges of the 21st Century. As greenhouse gas concentration of the atmosphere has reached the 400ppm threshold of a 2°C global warming on 9 May 2013 and irreversible tipping points of the climatic system at some point of time have got even more likely, the question of the individual contribution to climate change becomes more and more virulent. For a long time, the absorption capacity of the environment has been regarded as limitless, and based on this perception, the economic entities used the environment for hundreds of years without constraints. Today, with progress of scientific knowledge, we are now aware of the possible negative impacts of climate change to environmental, economic and social systems on Earth. This awareness, however, did not lead to a significant change of individual behavior, because the perceived individual contribution to both the anthropogenic cause of climate change and its mitigation is still regarded as marginal. To encounter this misperception or “diffusion of environmental responsibility”, this article presents an alternative calculation of the individual contribution to climate change taking the incremental approach to a tipping point or a 2°C global warming threshold into account. 展开更多
关键词 Climate change individual contribution Tragedy of the commons Diffusion of Environmental Responsibility Tipping Points 2 global Warming
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大气CO_(2)浓度升高对土壤供氮能力的影响研究
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作者 李佳燕 《农业灾害研究》 2023年第10期311-313,共3页
随着全球气候变化和人类活动的持续发展,大气中CO_(2)浓度持续上升,已经成为一个全球性的问题。大气CO_(2)浓度的升高对土壤生态系统的影响备受关注。其中,影响土壤供氮能力是一个重要问题。旨在探究大气CO_(2)浓度升高对土壤供氮能力... 随着全球气候变化和人类活动的持续发展,大气中CO_(2)浓度持续上升,已经成为一个全球性的问题。大气CO_(2)浓度的升高对土壤生态系统的影响备受关注。其中,影响土壤供氮能力是一个重要问题。旨在探究大气CO_(2)浓度升高对土壤供氮能力的影响,为深入研究土壤生态系统对气候变化的响应提供科学依据,也为实施有效的土壤保护和管理提供理论支持。 展开更多
关键词 气候变化 co_(2)浓度 土壤供氮能力
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LOW FREQUENCY VARIABILITY OF INTERANNUAL CHANGE PATTERNS FOR GLOBAL MEAN TEMPERATURE DURING THE RECENT 100 YEARS
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作者 刘晶淼 丁裕国 余锦华 《Journal of Tropical Meteorology》 SCIE 2002年第1期46-55,共10页
The TEEOF method that expands temporally is used to conduct a diagnostic study of the variation patterns of 1, 3, 6 and 10 years with regard to mean air temperature over the globe and Southern and Northern Hemispheres... The TEEOF method that expands temporally is used to conduct a diagnostic study of the variation patterns of 1, 3, 6 and 10 years with regard to mean air temperature over the globe and Southern and Northern Hemispheres over the course of 100 years. The results show that the first mode of TEEOF takes up more than 50% in the total variance, with each of the first mode in the interannual oscillations generally standing for annually varying patterns which are related with climate and reflecting long-term tendency of change in air temperature. It is particularly true for the first mode on the 10-year scale, which shows an obvious ascending trend concerning the temperature in winter and consistently the primary component of time goes in a way that is very close to the sequence of actual temperature. Apart from the first mode of all time sections of TEEOF for the globe and the two hemispheres and the second mode of the 1-year TEEOF, interannual variation described by other characteristic vectors are showing various patterns, with corresponding primary components having relation with long-term variability of specific interannual quasi-periodic oscillation structures. A 2T test applied to the annual variation pattern shows that the abrupt changes for the Southern Hemisphere and the globe come closer to the result of a uni-element t test for mean temperature than those for the Northern Hemisphere do. It indicates that the 2Ttest, when carried out with patterns of multiple variables, seems more reasonable than the t test with single elements. 展开更多
关键词 global mean temperature patterns of interannual variation abrupt change of climate 2T test
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Photosynthetic and Growth Responses to Elevated [CO2] are Determined by Multiple Forest Ecosystem Conditions
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作者 Titus Fondo Ambebe 《Journal of Life Sciences》 2014年第11期908-914,共7页
The responses of photosynthesis and growth of forest trees to rising atmospheric carbon dioxide concentration [CO2] are modified by ecosystem conditions. With the exception of a few, the vast majority of empirical stu... The responses of photosynthesis and growth of forest trees to rising atmospheric carbon dioxide concentration [CO2] are modified by ecosystem conditions. With the exception of a few, the vast majority of empirical studies on the impact of future high CO2 levels on forest trees have focused on [CO2] alone or in combination with an environmental factor. This paper uses the case of CO2 × nutrient and CO2 × nutrient-related interactions to evaluate the relative value of single or multiple ecosystem factors in determining the responses of photosynthesis and growth to elevated [CO2]. A comprehensive literature search was conducted with Google Scholar. The findings show a consensus among studies that CO2 and nutrient availability have synergistic effects on photosynthesis and growth. However, combinations of nutrient availability with temperature or moisture modify the CO2 effect in ways different from nutrient availability alone. To increase the predictive power of empirical studies, it is recommended that conclusions on the responses of forest trees to elevated atmospheric [CO2] be based on interactions with multiple, rather than single, ecosystem conditions. 展开更多
关键词 co2 elevation forest trees global change co2 × environment interactions.
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CONCENTRATION OF COUPLED CUBIC NONLINEAR SCHRDINGER EQUATIONS
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作者 李晓光 张健 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第10期1357-1362,共6页
A coupled nonlinear Schrodinger equations is considered in 2-D space. Based upon the conservation of mass and energy, local identities is established by the study of the limit behavior of the solutions, and L^2-concen... A coupled nonlinear Schrodinger equations is considered in 2-D space. Based upon the conservation of mass and energy, local identities is established by the study of the limit behavior of the solutions, and L^2-concentration for the blow-up solutions with radially symmetry is obtained. 展开更多
关键词 nonlinear Schrodinger equation global existence blow up blow-uppoint L^2-concentration
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