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cmip5多模式资料中气温的bma预测方法研究
智协飞？,王晶？,林春泽？,彭婷？,王佳？
气象科学 , 2015, DOI: 10.3969／2014jms.0052
Abstract: 利用cmip5的8个全球气候系统模式对气温的回报结果进行贝叶斯模式平均(简称bma)试验,并采用均方根误差、距平相关系数、连续等级概率评分等对多模式集合平均(简称emn)和bma的回报结果进行检验、评估。结果表明,emn的回报效果优于8个单模式的回报效果,而bma的回报效果最好,其区域平均的均方根误差比emn小0.5℃左右。在此基础上,利用中等排放情景rcp4.5下cmip5模式中的年际年代际预估资料对2011—2035年的气温进行预估。研究发现东亚地区在2011—2035年气温将普遍升高,海洋上的增暖幅度较小,陆地上的增暖幅度较大,且增暖幅度随纬度升高而增大。青藏高原及中国北方大部分地区气温将明显升高,升温幅度在1℃左右,而南方的升温幅度较小,约为0.3~0.6℃。
RCP4.5情景下中国季风区及降水变化预估
大气科学 , 2015, DOI: 10.3878/j.issn.1006-9895.1411.14216
Abstract: 本文使用国际耦合模式比较计划第五阶段(CMIP5)中共46个全球气候模式的数值试验结果,通过对中国区域的年、夏季和冬季降水气候态的模拟能力评估,择优选取了18个气候模式用来预估RCP4.5情景下21世纪中国季风区范围、季风降水及其强度变化。结果表明,相对于1986~2004年参考时段,RCP4.5情景下多数模式和所有模式集合平均在不同时段内均模拟出中国季风区面积、季风降水及其强度的增加趋势,最明显的时段出现在2081~2099年。其中,季风区面积扩张是导致季风降水增加的主要因素。在机制上,热力与动力条件变化均有利于季风降水强度的增加以及更多的水汽进入中国东部,从而引起季风区范围的扩大
中国干湿区变化与预估
大气科学 , 2017, DOI: 10.3878/j.issn.1006-9895.1604.15223
Abstract: 本文采用干湿指数对1962~2011年中国干湿区范围变化进行了集中分析，并利用CMIP5（Coupled Model Intercomparison Project Phase 5）模式对其变化趋势开展了预估研究。结果表明，1962~2011年平均极端干旱区、干旱区、半干旱区、半湿润区和湿润区分别占中国陆地总面积的2.8%、11.7%、22.4%、32.6%和30.5%。期间，中国区域年干湿指数总体上呈现下降趋势，空间上表现为西部湿润化和东部干旱化的特征。显著缩小的是湿润区和极端干旱区，半湿润区、半干旱区和干旱区则显著扩大，这表明中国气候敏感区域在扩张。春季和秋季干湿指数变化趋势的空间分布与年平均的较为一致，冬季西北呈干旱化，夏季东南部地区为湿润化。相对于参考时段1986~2005年，在RCP4.5（Representative Concentration Pathway 4.5）情景下18个气候模式中位数的预估结果中，降水仅在东南南部减少，而潜在蒸散发在全区域增加，由于潜在蒸散发的增量超过了降水的增幅，中国区域将整体趋于干旱化，仅在西北地区呈湿润化特征；未来湿润区、干旱区和极端干旱区缩小，气候敏感性高的半湿润区和半干旱区仍将扩大
Change in Climate Indices Using Bias-Adjusted CMIP5 Models: The Case Study of the Fatick Region, Senegal  [PDF]
Ibrahima Camara, Quentin Lejeune, Dimitri Defrance, Mame Diarra Bousso Dieng, Issa Sakho, Youssouph Sane, Mélinda Noblet, Moussa Diakhaté, Benjamen Sultan, Saidou Moustapha Sall, Sérigne Faye
American Journal of Climate Change (AJCC) , 2022, DOI: 10.4236/ajcc.2022.114015
Abstract: This study analyses change in rainfall and temperature indices by 2035 and 2050 in Senegal, with a focus on the Fatick region. These parameters are crucial for understanding the impacts of anthropogenic climate change on some vital socio-economic sectors such as agriculture and water resources in this region. To this end, a multi model ensemble mean of 21 bias-adjusted global climate models participating in CMIP5 has been used. We considered two Representative Concentration Pathways (RCP4.5 and RCP8.5). The results indicate an increase of 0.7˚C for maximum and minimum temperature by 2035 compared to the reference period (1976 - 2005). By 2050, an increase of 1.4˚C (2˚C) is projected for RCP4.5 (RCP8.5). These increases in temperature are statistically significant at the 90% confidence level. Conversely, the mean rainy season length decreases from 95 to 85 days by 2035 and less than 80 days by 2050. These decreases in rainy season length are mainly due to a delayed rainy season onset by 2035 and 2050, with the ensemble mean projecting an onset in the second half of July by 2050 instead of around the middle of June. The changes in both the onset and the length of the rainy season are significant at the 90% confidence level. Our results show a slight decrease in seasonal cumulated total rainfall by 2035 and 2050. However, we note a slight increase in seasonal cumulated extreme rainfall. These future changes in climate indices could induce yield reduction and water resources availability. To reduce yield losses, it would be interesting to adopt longer season varieties and also diversify income-generating activities. Concerning water resources, many actions could be done such as carrying out water retention works, treatment and reuse of non-conforming water for agriculture and livestock to reduce pressure on the resource.
Climate Services Elaboration for Cocoa Cultivation in C？te d’Ivoire: Contribution of CORDEX Climate Projections  [PDF]
Adama Bamba, Fidèle Yoroba, N’Datchoh Evelyne Toure, Kouakou Kouadio, Mory Ouattara, Kakou M’bo, Mamadou Cherif, Daouda Kone, Arona Diedhiou
Agricultural Sciences (AS) , 2024, DOI: 10.4236/as.2024.153021
Abstract: This study assessed the contribution of climate projections to improving rainfall information for cocoa crops in the central and southern regions of Côte d’Ivoire. Particular attention was paid to fourteen localities in these two climatic zones. Simulation data were obtained from the CORDEX ensemble and observation data from CHIRPS. They cover the period 1991-2005 for the reference period and the future period from 2021 to 2050 for the RCP4.5 and RCP8.5 scenarios. In addition, the study was based on the water requirements necessary during the critical phase of the cocoa tree (the flowering phase) for a good yield from the cocoa production chain on the one hand, and on a selection of three climate indices CDD, CWD and r95PTOT to study their spatio-temporal changes over two future periods 2021-2035 (near future) and 2036-2050 (medium-term) on the other. These climatic indices influence cocoa cultivation and their use in studies of climatic impacts on agriculture is of prime importance. The analysis of their spatio-temporal changes in this work also contributes to providing climate services based on rainfall, to which cocoa crops are highly sensitive. Our results show that the CDD and CWD indices vary from one region to another depending on latitude. For the fourteen localities studied, the number of consecutive dry days (CDD) could increase between now and 2050, while the number of consecutive wet days (CWD) could decrease over the period 2021-2035 and then increase over the period 2036-2050. The localities of Tabou, Aboisso and San-Pedro record high numbers of CDD index and CWD index for both projection scenarios. In comparison with the RCP4.5 and RCP8.5 scenarios, these results show that the RCP8.5 scenarios are having an impact on cocoa growing in Côte d’Ivoire.
Impacts of Climate Change on the Hydrology of a Small Brazilian Headwater Catchment Using the Distributed Hydrology-Soil-Vegetation Model  [PDF]
Lívia Alves Alvarenga, Carlos Rogério de Mello, Alberto Colombo, Sin Chan Chou, Luz Adriana Cuartas, Marcelo Ribeiro Viola
American Journal of Climate Change (AJCC) , 2018, DOI: 10.4236/ajcc.2018.72021
Abstract: Climate change is one of the greatest issues for human society. The objective of this study is to assess the impacts of future climate change on seasonal average discharge and monthly water budget in a small headwater catchment, located on the Grande River basin, in Minas Gerais, Brazil. The assessment is carried out using the hydrology model, DHSVM. The atmospheric forcing to drive the Distributed Hydrology-Soil-Vegetation Model (DHSVM) is derived from the downscaling of the HadGEM2-ES projections by the Eta Regional Climate Model, at 5-km high resolution. The projections assume the RCP4.5 and RCP8.5 IPCC AR5 emission scenarios. Baseline period was taken between 1961 and 1990. The projections are assessed in three time slices (2011-2040, 2041-2070 and 2071-2099). The climate change is assessed in time slices of 30 years and in comparison against the baseline period to evaluate the hydrological changes in the catchment. The results showed differences in the hydrological behavior between the emission scenarios and though time slices. Reductions in the magnitude of the seasonal average discharge and monthly water budget may alter the water availability. Under the RCP4.5 scenario, results show greater reductions in the water availability in the first time slice, whereas under RCP8.5 scenario greater reductions are indicated in the third time slice.
未来RCP4.5情景下非洲地区主要气候要素时空演变特征
戴君虎, 邵全琴, 陈鹏飞,刘玉洁
- , 2016,
Abstract: 摘要： 气候变化影响及其适应受到广泛关注。大量研究表明,受气候变化影响所造成的增温和降水减少已影响到非洲地区的农业生产和环境。本文利用HadGEM2区域气候模式输出的RCP4.5情景数据,基于时间序列分析及空间分析方法,对非洲大陆2010-2099年主要关键气候要素时空演变特征进行了预估,探讨了非洲大陆未来90年包括降水、辐射、平均气温、最高气温、最低气温等主要气候要素的时空变化格局。结果表明：各气候要素在不同时段的变化均表现出明显的地域分异差异： ① 相较于1970-1999年基准时段,未来3个时段(2020s、2050s、2080s)降水均增加,在2080s增至峰值,增加地区集中在20 °N附近的尼日尔、乍得、利比亚等国;最高增幅达4.5%;② 辐射增加区域分布在赤道地区和非洲大陆的南北两端,尤其是高海拔地区,如撒哈拉沙漠以北的阿特拉斯山脉附近,加丹加高原等地,最大增幅达0.04%;③ 未来90年非洲地区气温增加明显,包括平均气温、最高气温、最低气温,气温增幅由2020s、2050s、2080s依次递增,到2080s达到最大值,平均气温、最高气温、最低气温的最大增幅分别达到5、4.3和5.1 ℃。总体上,未来90年非洲大陆的气温较1970-1999年基准时段明显增多,但靠近海域的沿海地区增温较小,这是由于受到近海寒流的影响,起到了降温的作用。气温增幅过高也将不利于未来农业生产和地区安全。
RCP4.5情景下中国人口对高温暴露度预估研究
杨冰韵, 黄大鹏,张蕾
- , 2016, DOI: 10.11821/dlyj201612004
Abstract: 摘要： 基于CMIP5的逐日最高温度模拟资料、GGI情景数据库逐年代人口数据,在RCP4.5情景下,以对应栅格高温日数与人口数量的乘积作为人口对高温的暴露度指标,通过多模式集合平均预估未来中国人口对不同强度高温的暴露度变化。结果表明：相比于基准时段（1981-2010年）,中国人口对高温和强危害性高温的暴露度从2021-2040年开始明显增加,至2081-2100年暴露度分别增加了5.7倍和17.5倍;除了中国西部部分地区外,全国大部地区人群均受高温的影响,在21世纪中后期中东部大部人口对高温的暴露度超过10.0×106人?d;相比基准时段,随着年代的增长,中国人口对强危害性高温的暴露度在范围和强度上均有明显增加;2081-2100年,人口对高温和强危害性高温的暴露度增幅减缓。从气象地理区域上看,未来各时段人口对高温、强危害性高温的暴露度均有一定程度增加,但增加明显的区域主要集中在华北、黄淮、江南和江淮地区,华南地区对强危害性高温的暴露度增幅较小。高温日数变化对全国人口对高温暴露度的变化所产生的作用最明显。多模式集合的预估结果可以为防控未来高温风险提供重要的参考价值。
21世纪格陵兰冰川融化速率对海平面变化的影响
左军成,李娟,谭伟,赵雪,陈美香
华东政法大学学报 , 2015,
Abstract: 本文利用大洋环流模式POP研究RCP4.5情景下21世纪格陵兰冰川不同的融化速率对全球及区域海平面变化的影响.结果显示:当格陵兰冰川的融化速率以每年1%增加时,全球大部分海域的动力和比容海平面变化基本不变,主要是由于格陵兰冰川在低速融化时并不会导致大西洋经向翻转流减弱.当格陵兰冰川的融化速率以每年3%和每年7%增加时,动力海平面在北大西洋副极地、大西洋热带、南大西洋副热带和北冰洋海域呈现出显著的上升趋势,这是因为格陵兰冰川快速融化导致大量的淡水输入附近海域,造成该上层海洋层化加强和深对流减弱,导致大西洋经向翻转流显著减弱;与此同时,热比容海平面在北冰洋、格陵兰岛南部海域和大西洋副热带海域显著下降,而在热带大西洋和湾流海域明显上升;此时盐比容海平面的变化与热比容海平面是反相的,这是由于大量的低温低盐水的输入,造成北大西洋副极地海域变冷变淡、大西洋经向翻转流和热盐环流显著减弱,引起了太平洋向北冰洋的热通量和淡水通量减少,导致了北冰洋海水变冷变淡,同时热带大西洋滞留了更多的高温高盐水,随着湾流被带到北大西洋,北大西洋副极地海域低温低盐的海水,被风生环流输运到副热带海域
RCP4.5情景下淮河流域气候变化的高分辨率模拟
刘青, 张正涛, 陈实,高超
- , 2014, DOI: 10.11821/dlyj201403006
Abstract: 摘要： 利用CCLM高分辨率区域气候模式RCP4.5情景预估数据与淮河流域1960-2005年日尺度气象观测资料，对比分析模式在试验期（1960-2005年）和预估期（2006-2040年）的模拟能力。结果表明：①试验期模式数据能较准确地模拟流域逐月平均温度时间变化特征，相关系数达0.99（通过95%置信度检验）；日均温空间分布特征相关系数达0.72；但在南部高海拔地区（安徽省霍山县和金寨县）精度不高；极端最高（低）气温的空间相关性达0.77（0.88）。②模式在试验期模拟的逐月平均降水量总体趋势与实测值变化一致，相关系数达0.63（通过95%置信度检验）；对干旱的模拟与观测数据存在一定误差，但整体趋势与其一致；年均降水量和极端强降水空间分布相关系数分别达0.90和0.93，模拟效果较好；整体上，模式对温度的模拟效果要好于降水模拟。③RCP4.5情景下，空间尺度上淮河流域未来温度和降水与观测期相比变幅小，时间尺度上年均降水量无显著变化，平均气温年际变化率约0.21℃/10a，极端高温持续增长，低温持续下降
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