Impact of urbanization and land-use change on climate

The most important anthropogenic influences on climate are the emission of greenhouse gases and changes in land use, such as urbanization and agriculture. But it has been difficult to separate these two influences because both tend to increase the daily mean surface temperature. The impact of urbanization has been estimated by comparing observations in cities with those in surrounding rural areas, but the results differ significantly depending on whether population data or satellite measurements of night light are used to classify urban and rural areas. Here we use the difference between trends in observed surface temperatures in the continental United States and the corresponding trends in a reconstruction of surface temperatures determined from a reanalysis of global weather over the past 50 years, which is insensitive to surface observations, to estimate the impact of land-use changes on surface warming. Our results suggest that half of the observed decrease in diurnal temperature range is due to urban and other land-use changes. Moreover, our estimate of 0.27 degrees C mean surface warming per century due to land-use changes is at least twice as high as previous estimates based on urbanization alone.     

Impact of climate change on marine pelagic phenology and trophic mismatch

Phenology, the study of annually recurring life cycle events such as the timing of migrations and flowering, can provide particularly sensitive indicators of climate change. Changes in phenology may be important to ecosystem function because the level of response to climate change may vary across functional groups and multiple trophic levels. The decoupling of phenological relationships will have important ramifications for trophic interactions, altering food-web structures and leading to eventual ecosystem-level changes. Temperate marine environments may be particularly vulnerable to these changes because the recruitment success of higher trophic levels is highly dependent on synchronization with pulsed planktonic production. Using long-term data of 66 plankton taxa during the period from 1958 to 2002, we investigated whether climate warming signals are emergent across all trophic levels and functional groups within an ecological community. Here we show that not only is the marine pelagic community responding to climate changes, but also that the level of response differs throughout the community and the seasonal cycle, leading to a mismatch between trophic levels and functional groups.     

气候变化对黄河流域的影响及应对措施

分析了全球气候变化对黄河流域区域气候、水资源量、生态格局、农业牧业生产、地质灾害、文物保护的影响,阐述了应对研究的主要进展及存在的主要问题,探讨了气候变化对黄河流域影响的未来趋势,提出了进一步研究工作的建议:即统筹建设黄河流域气象、水文、环境、地质灾害观测和预报预警系统;厘清多因素影响下的流域水资源时空过程,提升流域水资源效能;调整坡耕地和生态用地,加强流域水源涵养能力;加强植物生理生态适应性研究,优化流域农业和草业布局;修订文化遗产赋存环境区划,进行预防性保护技术研发;加强流域黄土滑坡加固新材料和生态修复协同技术研究。     

气候变化对衢州水文站洪水频率分析的影响

以衢州水文站为研究对象,针对衢州水文站的年最大值序列,选择广义极值分布作为该站洪水频率分析的分布函数,使用30a滑动平均法对线性矩估计所得分布函数参数的变化趋势进行分析,通过研究气候变化对衢州水文站洪水频率分析统计参数的影响来研究水文流量序列对气候变化的敏感程度.研究结果表明,气候变化对频率分析分布曲线的参数有较大影响,从而影响最终设计洪水的数值.     

Impact of land surface degradation in northern China and southern Mongolia on regional climate

Clear evidence provided by the singular value decomposition (SVD) analysis to the normalized difference vegetation index (NDVI) and precipitation data identifies that there exists a sensitive region of vegetation-climate interaction located in the transitional zone over northern China and its surrounding areas, where the vegetation cover change has the most significant influence on summer precipitation over China.““ Comparison of reanalysis data with station data provides a good method to assess the impacts of land use change on surface temperature, and the most obvious contribution of land use change may be to lead to notable warming over northern China in the interdecadal time scale. Based on the new statistical results, a high-resolution regional integrated environmental model system (RIEMS) is employed to investigate the effects of land surface degradation over the transitional zone and its surrounding areas (northern China and southern Mongolia) on the regional climate. Land degradation results in the decreases in precipitation over northern and southern China, and the increase in between, and increased and decreased temperature over vegetation change areas and the adjacent area to the south, respectively. Not only would it change the surface climate, but also bring the significant influence on the atmospheric circulation. Both the surface climate and circulation changes generally agree to the observed interdecadal anomalies over the last five decades. These integrated statistical and simulated results imply that land surface degradation over the transitional zone in northern China and its surrounding areas could be one of the main causes responsible for the climate anomalies over China, especially the drought over northern China.     

气候变化对湖南省马尾松适宜生境影响分析

【目的】气候变化会导致树种适宜生境发生变化,从而对准确地制定长期森林经营规划方案产生影响。为了在制定长期森林经营规划中贯彻适地适树原则,需要研究气候变化对树种适宜生境分布的影响。【方法】以湖南省马尾松(Pinus massoniana)为研究对象,利用2016年湖南省连续清查森林资源档案更新数据中的马尾松空间分布数据、高程数据和气候数据,采用最大熵法(Maxent)模型,分温度变化、降水量不变,降水量变化、温度不变,降水量和温度均变化3种情景模拟马尾松在湖南省适宜生境的动态变化。【结果】① Maxent模型模拟结果中,训练精度、模拟精度的AUC(area under the ROC curve)值在AUC评估标准中属于良好(0.80～0.90)水平,可以较好地模拟马尾松适宜生境; ② 2016年马尾松适宜生境主要分布于湖南省中部和西北部,小部分分布于东部和南部。适宜生境、低适宜生境和不适宜生境所占面积比例分别为28.30%、40.10%、31.60%; ③ 2016—2050年温度和降水量均有所增加,年平均温度增加2.30 ℃,年平均降水量增加19.9 mm。在温度升高、降水量不变,降水量升高、温度不变和温度、降水量均升高3种气候情景下,湖南省马尾松适宜生境面积比例分别变化了0.58%、0.53%和-0.65%,不适宜生境相比2016年均有所减少,分别减少了7.22%、2.00%和0.15%; ④ 刀切法确定了最湿季均温(Bio8)、最暖季均温(Bio10)、最冷季降水量(Bio19)为影响马尾松分布的主导气候因子,其中最冷季降水量为最主要的气候因子。【结论】湖南省马尾松种植区主要分布在该省中部和西北部,当未来气候呈现温度增加、降水量不变的情景时,种植区域适当向东扩展; 当未来气候呈现降水量增加、温度不变或二者均增加的情景时,种植区域适当向北扩展。     

黄垒河流域气候与土地利用变化对径流的影响

以山东胶东半岛黄垒河流域为研究区,构建了SWAT分布式水文模型,采用SUFI-2算法进行模型参数敏感性分析、率定与验证研究,对巫山水文站2011—2018年月径流量数据进行模拟,在此基础上设置3类变化情景,定量识别黄垒河流域内气候变化与土地利用变化下的水文响应情况.结果表明:1)SWAT模型在黄垒河径流模拟中具有较好的适用性,模型率定期的R²、E_NS分别为0.74和0.71,验证期R²、E_NS分别为0.69和0.72;2)综合型情景模拟分析得出,气候变化、土地利用变化及二者共同变化均引起流域内年均径流增加,分别使年均径流量增加0.14、0.05、0.19 m³·s^-1,径流量对气候变化比土地利用变化更敏感,径流变化由气候变化主导;3)气候变化情景模拟分析得出,流域内年均径流量与降水变化成正相关,降水增加比降水减少对径流变化作用更显著,气温升高对流量变化有负效应,流量对气温升高比气温降低更敏感;4)极端土地利用情景模拟分析得出,城市扩张情景、耕地保护情景、退...     

Impact of climate change on streamflow in the Xitiaoxi catchment, Taihu Basin

The impact of climate change on streamflow in the Xitiaoxi catchment is assessed by using VIC (variable infiltration capacity) model coupled with PRECIS (providing regional climate for impacts studies). Results show that the VIC model is adaptable for the study area. Both deterministic coefficient and Nash-Suttcliffe efficiency coefficient are greater than 0.75, with a good agreement between observed and simulated discharge. The runoff will increase in the future, especially during flood seasons. The magnitude of floods in the future (2021–2050) under A2 and B2 scenarios will be greater than that during the baseline period (1961–1990), but it may not exceed that during the 1990s.     

气候变化对浙江楠潜在分布范围及空间格局的影响

气候变化对物种分布的影响是珍稀濒危物种资源保护研究的热点问题之一。利用Maxent模型预测浙江楠在末次盛冰期、全新世中期、现代和2070年4个历史时期的潜在分布区,分析浙江楠各个历史时期的分布格局,并评估了不同气候因子对其潜在地理分布的影响。结果表明,Maxent模型模拟现代分布区准确度极高,受试者工作特征曲线下的面积(AUC值)达0.996。高度适生区包括浙江省与福建省交汇的武夷山、仙霞岭、浙江东南部的洞宫山、雁荡山等较高海拔山地地带,中度适生区位于幕阜山、罗霄山、怀玉山、武夷山、黄山、天目山、会稽山、雁荡山、洞宫山等低海拔丘陵地区。末次盛冰期浙江楠潜在分布区位于东海大陆架内; 全新世中期分布区与现代相似,但面积更大,向低海拔地区延伸; 2070年潜在分布区有北扩东进的趋势。Jackknife检验表明,影响浙江楠地理分布的主要因子有最干季降水量、最冷季降水量和最干季均温。     

露天矿排土场植被恢复的小气候变化效应

结合阜新海州露天矿排土场土地复垦工作的进行,通过现场调研与测试,分别对排土场区域不同生态类型条件下的气温、地表温度、地温、土壤水分等实际情况进行了观测,进一步分析得出排土场植被恢复后的小气候变化的生态效应得到明显改善.     

基于变化速度特征视角的我国区域创新生态系统健康性综合评价

创新生态系统作为引领区域创新协调发展的重要路径,其健康性水平的提升对于区域创新生态系统的高质量发展具有重要的意义.该研究采用具有速度特征的动态综合评价模型,对我国30个省市的区域创新生态系统健康性进行综合评价研究.研究结果表明：全国区域创新生态系统的健康性水平从东向西呈阶梯状递减,区域创新生态系统健康性水平差距悬殊;多样性水平快速提升带动四川等省市区域创新生态系统健康性水平的增长;系统活力水平的增长促进了广东等省市区域创新生态系统健康性水平的良性提升;抵抗力水平对于区域创新生态系统健康性的提升作用并不明显;全国大部分省市的区域创新生态系统可持续性水平呈下降趋势.各省市应该结合实际情况因地制宜研究提升区域创新生态系统健康性水平的靶向路径,制定精准的政策供给,促进区域创新生态系统健康性水平的提升,助力区域创新生态系统实现高质量发展.     

Effects of climate change on biodiversity

1 Rise of studies on climate change＇s effects on biodiversity
Until the 1980s, climate change and biodiversity were studied as two independent disciplines for more than a century. In 1992, the Ecological Society of America＇s annual report named climate change, biodiversity, and the sustainable ecological system as the three major global environmental issues of the twenty-first century [1].     

气候变化影响下的流域水循环：回顾与展望?

随着全球气候变化的影响日益加剧,气候变化对流域水循环影响的研究成为普遍关注的焦点.数理统计和水文模拟两大手段的运用贯穿于过去30余年的研究当中,本文就其中所涉及的水文气象要素趋势分析、大气环流模式(GCMs)评估、降尺度技术及其选择、水文模型及其选择、不确定性分析5大内容的研究成果进行回顾与展望,以拉萨河流域为例综合运用前述技术分析区域气候变化特征及其对流域径流的影响.结果表明,在未来经济社会发展与气候变化情景下,流域径流时空分布不均匀性更加显著,具体表现为集中性增强,这给区域防洪抗旱与水资源配置等都带来了巨大挑战.通过系统阐述如何开展气候变化对流域水循环的影响研究及所包含的关键问题,可为后续相关研究和区域水资源管理提供科学依据与决策支撑.     

“柳叶刀倒计时：人群健康与气候变化”2020年度报告解读

 气候变化会严重威胁人群健康，任何国家都无法避免气候变化对健康的影响。为了应对这一危机，伦敦大学学院和清华大学联合全球30余家学术机构于2016年共同成立了“柳叶刀倒计时：追踪人群健康与气候变化进展”项目，并合作撰写了《柳叶刀倒计时：人群健康与气候变化》重大报告，以追踪气候变化对人群健康的影响以及应对气候变化带来的人群健康效益，同时开展公众宣传、提出政策建议。2020年的报告在追踪了5大领域43个指标的年度变化后发现，气候变化影响、暴露和脆弱性相关的指标全部都在恶化，但各国为减缓气候变化所做的努力却明显不足，以现在的趋势很难达到《巴黎协定》设定的2℃温升控制目标。新冠肺炎疫情全球大流行和气候变化带来了相互叠加的危机，需要共同应对。多重危机的共同应对可以为全社会实现三赢：更好的公共卫生条件、可持续的经济发展以及对环境的保护和改善。     

江苏沿海地区NDVI的演变特征及其对区域气候变化的响应

以江苏沿海地区为研究对象,利用1998—2008年从SPOT VEGETATION中提取的归一化植被指数(NDVI)资料,分析江苏沿海地区植被覆盖的时空变化规律。结果表明:(1)江苏沿海地区的NDVI有明显的季节变化,春季3、4月份及夏季7、8月份NDVI指数上升明显;近10年来,江苏沿海地区植被覆盖率呈增加趋势,植被状况有所改善。(2)1999年江苏沿海地区NDVI具有明显的区域差异,其表现为盐城较高、连云港次之、南通较低;到2007年连云港、南通地区NDVI明显增加,盐城地区总体增加,但区域差异较大,部分地区还出现了明显的下降趋势。(3)江苏沿海地区气候(气温、降水)因素对NDVI影响作用明显,二者均对NDVI有显著的正相关性,其中气温是主导因素。     

云南近50年极端气温及降水事件变化特征与区域气候变暖的关系

利用19612008年云南125个观测站的逐日观测资料,采用百分位值法定义了云南极端气温、降水事件阈值,分析了极端条件下的高温、低温和强降水的分布特征、气候变化趋势及其与区域气候变暖的关系.结果表明,云南极端高温阈值大于36℃的中心分别在低海拔的金沙江河谷、红河河谷及昭通和西双版纳的部分河谷地区.全省大部分地区极端高温频数具有明显的年代际变化特征.极端低温阈值小于-10℃的低值中心则集中位于迪庆州北部.大部分地区极端低温频数呈明显减少趋势.极端强降水阈值超过40mm的大值中心有3个,分别位于玉溪南部红河南部、普洱南部和曲靖南部.年平均气温与极端高温频数为正相关关系,与极端低温频数为显著的负相关关系,与极端强降水频数的相关关系不明显.     

生态环境变化对区域经济发展的影响研究——以贵阳市偏坡乡为例

以贵阳市偏坡乡为对象,采用生态环境、资源利用、生物多样性保护等方面对经济发展相关性影响较大的指标,进行区域生态环境变化对经济发展影响的DEA分析研究。结果表明:对偏坡乡近期经济发展影响较大的生态环境变化指标为新增林地面积、植物群落多样性、新增灌溉面积三方面,三者对经济发展贡献率分别为2.75%、36.01%、12.33%,其中代表生物多样性的植物群落多样性植被对区内经济发展影响最大。     

Coupling methods of global climate models and regional climate models

The future climate dynamical downscaling method is that output of general circulation models (GCMs) is employed to provide initial conditions,lateral boundary conditions,sea surface temperatures,and initial land surface conditions to regional climate models (RCMs).There are two methods of downscaling:offline coupling and online coupling.The two kinds of coupling methods are described in detail by coupling the Weather Research and Forecasting model (WRF) with the Institute of Atmospheric Physics of Chinese Academy of Sciences Atmospheric General Circulation Model Version 4.0 (IAP AGCM4.0) in the study.And the extreme precipitation event over Beijing on July 21 2012 is simulated by using the two coupling methods.Results show that online coupling method is of great value in improving the model simulation.Furthermore,the data exchange frequency of online coupling has some effect on simulation result.     

气候变化和人类活动对汀江径流变化的贡献

基于汀江流域控制站溪口站19652012年日均径流量实测数据及长汀、上杭、永定气象站逐日降水、逐日气温资料,采用年段均值比较、5a滑动、趋势线分析和累积距平等方法,对流域近50年来的径流量序列进行分析,揭示径流量变化的趋势,判别径流量变化存在的2个突变年份,划分径流量变化的3个阶段. 应用改进后累积量斜率变化率比较法（SCRCQ）定量估算了近50年来气候变化和人类活动对汀江径流量变化的贡献率. 结果表明：（1）径流量总体呈现下降上升下降的波动,判别突变年份为1972、2001年,划分径流变化3个阶段为19651972年(A阶段)、19732001年(B阶段)、20022012年（C阶段）;（2）与A阶段相比,B、C阶段气候变化对径流量变化的贡献率分别为65.1%、50.5%,而人类活动对径流量变化的贡献率为34.9%、49.5%,可见人类活动对径流量变化贡献日趋突出.