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Impact of Climate Change on Vegetation Distribution and Net Primary Productivity of Forests of Himalayan River Basins: Brahmaputra, Koshi and Indus 被引量:1
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作者 A. Chaitra S. Upgupta +12 位作者 L. D. Bhatta J. Mathangi D. S. Anitha K. Sindhu Vidya Kumar N. K. Agrawal M. S. R. Murthy F. Qamar Indu K. Murthy J. Sharma R. K. Chaturvedi G. Bala N. H. Ravindranath 《American Journal of Climate Change》 2018年第2期271-294,共24页
The impacts of climate change in terms of forest vegetation shifts and Net Primary Productivity (NPP) changes are assessed for Brahmaputra, Koshi and Indus river basins for the mid (2021-2050) and long (2071-2100) ter... The impacts of climate change in terms of forest vegetation shifts and Net Primary Productivity (NPP) changes are assessed for Brahmaputra, Koshi and Indus river basins for the mid (2021-2050) and long (2071-2100) terms for RCP4.5 and RCP8.5 scenarios. Two Dynamical Global Vegetation Models (DGVMs), Integrated BIosphere Simulator (IBIS) and (Lund Postdam and Jena (LPJ), have been used for this purpose. The DGVMs are driven by the ensemble mean climate projections from 5 climate models that contributed to the CMIP5 data base. While both DGVMs project vegetation shifts in the forest areas of the basins, there are large differences in vegetation shifts projected by IBIS and LPJ. This may be attributed to differing representation of land surface processes and to differences in the number of vegetation types (Plant Functional Types) defined and simulated in the two models. However, there is some agreement in NPP changes as projected by both IBIS and LPJ, with IBIS mostly projecting a larger increase in NPP for the future scenarios. Despite the uncertainties with respect to climate change projections at river basin level and the differing impact assessments from different DGVMs, it is necessary to assess the “vulnerability” of the forest ecosystems and forest dependent communities to current climate risks and future climate change and to develop and implement resilience or adaptation measures. Assessment of the “vulnerability” and designing of the adaptation strategies could be undertaken for all the forested grids where both IBIS and LPJ project vegetation shifts. 展开更多
关键词 Climate CHANGE FORESTS HIMALAYAN River BASINS Impacts NPP CHANGE Forest Type SHIFT
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Changes of Atmospheric Water Balance over China under the IPCC SRES A1B Scenario Based on RegCM3 Simulations
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作者 SUN Bo JIANG Da-Bang 《Atmospheric and Oceanic Science Letters》 2012年第6期461-467,共7页
Simulations of the Regional Climate Model Version 3 (RegCM3) under the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) A1B scenario were employed to investigate possible d... Simulations of the Regional Climate Model Version 3 (RegCM3) under the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) A1B scenario were employed to investigate possible decadal changes and long-term trends of annual mean atmospheric water balance components over China in the 21st century with reference to the period of 1981-2000. An evaluation showed that RegCM3 can reasonably reproduce annual evapotranspiration, precipitation, and water vapor transport over China, with a better performance for March-June. It was found that the water vapor exchange between the land surface and atmosphere would be significantly intensified in Northwest China by the mid-to late-21st century and that the region would possibly shift to a wetter or drought-mitigated state under global warming. Conversely, the water vapor exchange evidently weakened over the Tibetan Plateau and South-west China by the mid-to late-21st century. In addition, there appears to be a drier state for Northeast China and the middle and lower reaches of the Yangtze River valley by the mid-to late-21st century, with slight mitigation by the end compared with the mid-21st century. The westerly and southwesterly water vapor transport over China generally presents an increasing trend, with increasing diver-gence over the Tibetan Plateau and Northeast China, corresponding to a loss of atmospheric water vapor by water vapor transport. 展开更多
关键词 REGCM3 A1B scenario atmospheric water balance
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Selected fermented indigenous vegetables and fruits from Malaysia as potential sources of natural probiotics for improving gut health 被引量:1
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作者 Olaide Olawunmi Ajibola Raymond Thomas Babatunde Femi Bakare 《Food Science and Human Wellness》 SCIE CSCD 2023年第5期1493-1509,共17页
In the Peninsular Malaysia and Northern Borneo island of Malaysia, various rich indigenous leafy vegetables and fruits grow and contribute to the nutritional and dietary values of the population. They have high water ... In the Peninsular Malaysia and Northern Borneo island of Malaysia, various rich indigenous leafy vegetables and fruits grow and contribute to the nutritional and dietary values of the population. They have high water contents, thus, naturally vulnerable to rapid food spoilage. Food preservation and processing play a vital role in the inhibition of food pathogens in fruits and vegetables that are prevalent in Malaysia. Lactic acid fermentation is generally a local-based bioprocess, among the oldest form and well-known for food-processing techniques among indigenous people there. The long shelf life of fermented vegetables and fruits improves their nutritional values and antioxidant potentials. Fermented leaves and vegetables can be utilized as a potential source of probiotics as they are host for several lactic acid bacteria such as Lactobacillus confusus, Weissella paramesenteroides, Enterococcus faecalis, Lactobacillus plantarum, Lactobacillus buchneri, Lactobacillus paracasei, Lactobacillus pentosus, Pediococcus acidilactici, Pediococcus pentosaceus and Leuconostoc mesenteroides. These strains may be more viable in metabolic systems whereby they can contribute to a substantial increase in essential biologically active element than industrial starter cultures. This review is aimed to address some essential fermented fruits and vegetables in Malaysia and their remarkable reputations as a potential sources of natural probiotics. 展开更多
关键词 ETHNIC Leafy vegetables FRUIT FERMENTATION Lactic acid bacteria MALAYSIA
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Influence of Internal Decadal Variability on the Summer Rainfall in Eastern China as Simulated by CCSM4 被引量:7
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作者 Yali ZHU Tao WANG Jiehua MA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第6期706-714,共9页
The combined impact of the Pacific Decadal Oscillation (PDO) and Atlantic Multidecadal Oscillation (AMO) on the summer rainfall in eastern China was investigated using CCSM4. The strongest signals occur with the c... The combined impact of the Pacific Decadal Oscillation (PDO) and Atlantic Multidecadal Oscillation (AMO) on the summer rainfall in eastern China was investigated using CCSM4. The strongest signals occur with the combination of a positive PDO and a negative AMO (+PDO- AMO), as well as a negative PDO and a positive AMO (-PDO + AMO). For the +PDO- AMO set, significant positive rainfall anomalies occur over the lower reaches of the Yangtze River valley (YR), when the East Asian summer monsoon becomes weaker, while the East Asian westerly jet stream becomes stronger, and ascending motion over the YR becomes enhanced due to the jet-related secondary circulation. Contrary anomalies occur over East Asia for the -PDO + AMO set. The influence of these two combinations of PDO and AMO on the summer rainfall in eastern China can also be observed in the two interdecadal rainfall changes in eastern China in the late 1970s and late 1990s. 展开更多
关键词 Pacific Decadal Oscillation Atlantic Multidecadal Oscillation eastern China summer rainfall CCSM4
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The Relationship between Melt Season Sea Ice over the Bering Sea and Summer Precipitation over Mid-Latitude East Asia 被引量:5
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作者 Yurun TIAN Yongqi GAO Dong GUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第6期918-930,共13页
Independent datasets consistently indicate a significant correlation between the sea ice variability in the Bering Sea during melt season and the summer rainfall variability in the Lake Baikal area and Northeastern Ch... Independent datasets consistently indicate a significant correlation between the sea ice variability in the Bering Sea during melt season and the summer rainfall variability in the Lake Baikal area and Northeastern China.In this study,four sea ice datasets(HadISST1,HadISST2.2,ERA-Interim and NOAA/NSIDC)and two global precipitation datasets(CRU V4.01 and GPCP V2.3)are used to investigate co-variations between melt season(March−April−May−June,MAMJ)Bering Sea ice cover(BSIC)and summer(June−July−August,JJA)East Asian precipitation.All datasets demonstrate a significant correlation between the MAMJ BSIC and the JJA rainfall in Lake Baikal−Northeastern China(Baikal−NEC).Based on the reanalysis datasets and the numerical sensitivity experiments performed in this study using Community Atmospheric Model version 5(CAM5),a mechanism to understand how the MAMJ BSIC influences the JJA Baikal−NEC rainfall is suggested.More MAMJ BSIC triggers a wave train and causes a positive sea level pressure(SLP)anomaly over the North Atlantic during MAMJ.The high SLP anomaly,associated with an anti-cyclonic wind stress circulation anomaly,favors the appearance of sea surface temperature(SST)anomalies in a zonal dipole-pattern in the North Atlantic during summer.The dipole SST anomaly drives a zonally orientated wave train,which causes a high anomaly geopotential height at 500 hPa over the Sea of Japan.As a result,the mean East Asian trough moves westward and a low geopotential height anomaly occurs over Baikal−NEC.This prevailing regional low pressure anomaly together with enhanced moisture transport from the western North Pacific and convergence over Baikal−NEC,positively influences the increased rainfall in summer. 展开更多
关键词 Bering Sea ice North Atlantic SST East Asian summer precipitation wave train
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Extreme spring cold spells in North China during 1961–2014 and the evolving processes 被引量:3
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作者 Ya-Li ZHU Hui-Jun WANG +1 位作者 Tao WANG Dong GUO 《Atmospheric and Oceanic Science Letters》 CSCD 2018年第5期432-437,共6页
This study presents the major features of extreme spring cold spells(ESCS)in North China during 1961–2014 and the evolving processes.During an ESCS,northern Eurasia is controlled by large-scale positive SLP anomalies... This study presents the major features of extreme spring cold spells(ESCS)in North China during 1961–2014 and the evolving processes.During an ESCS,northern Eurasia is controlled by large-scale positive SLP anomalies and an anomalous anticyclone that continuously transport northern cold air to North China,causing significant,persistent,lower-than-normal daily temperatures.In fact,these positive SLP and anticyclonic wind anomalies begin to appear over northwestern Europe about 10 days prior to the ESCS.The anticyclonic wind anomalies keep moving southeastward and expand to the west of Lake Baikal until two days before the ESCS.Then,the center of the anomalous low-level anticyclone moves over Lake Baikal,inducing northerly wind anomalies that transport cold air into North China.In the following days,as the positive SLP anomalies weaken,the anomalous anticyclone and related northerly winds appear to wane,and the ESCS gradually comes to an end.The results may prove meaningful for the prediction and early warning of ESCSs. 展开更多
关键词 Spring cold spell North China spring temperature extreme weather
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空间尺度转换与跨尺度信息链接:区域生态水文模拟研究空间尺度转换方法综述(英文) 被引量:1
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作者 吴江华 赵鹏祥 +2 位作者 Nigel Roulet Jonathan Seaquist PENG Changhui 《地球科学进展》 CAS CSCD 北大核心 2008年第2期129-141,共13页
空间尺度转换是近年来区域生态水文研究领域的一个基本研究问题。其需要主要是源于模型的输入数据与所能提供的数据空间尺度不一致以及模型所代表的地表过程空间尺度与所观测的地表过程空间尺度不吻合。综述了目前区域生态水文模拟研究... 空间尺度转换是近年来区域生态水文研究领域的一个基本研究问题。其需要主要是源于模型的输入数据与所能提供的数据空间尺度不一致以及模型所代表的地表过程空间尺度与所观测的地表过程空间尺度不吻合。综述了目前区域生态水文模拟研究中常用的空间尺度转换研究方法,包括向上尺度转换和向下尺度转换。详细论述了2种向下尺度转换方法:统计学经验模型和动态模型。前者是通过将GCM大尺度数据与长期的历史观测数据比较从而建立统计学相关模型,然后利用这个统计学经验模型进行向下的空间尺度转换.然而动态模型并不直接对GCM数据进行向下尺度的转换,而是对与GCM进行动态耦合的区域气候模型(RCM)的输出数据进行空间尺度转换.通常后者所获得的数据精度要比前者高,但是一个主要缺点就是并不是全球所有的研究区域都有对应的RCM。还详细论述了2种向上尺度转换方法:统计学经验模型和斑块模型。前者是建立一个能代表小尺度信息在大尺度上分布的密度分布概率函数,然后利用这个函数在所需的大尺度上进行积分而求得大尺度所需的信息。而后者是根据相似性最大化原则将大尺度划分为若干个可操作的小尺度斑块,然后将计算的每个小尺度斑块的信息平均化得到大尺度所需的信息。通常在计算这种斑块化的小尺度信息的时候,对每个小尺度也会采用统计学经验模型来计算代表整个斑块小尺度的信息。 展开更多
关键词 生态水文模拟 空间尺度转换 向上空间尺度转换 向下空间尺度转换
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Validation for a tropical belt version of WRF: sensitivity tests on radiation and cumulus convection parameterizations 被引量:1
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作者 SUN Bi-Yun BI Xun-Qiang 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第3期192-200,共9页
Version 3.9 of WRF-ARW is run with a tropical belt configuration for a period from 2012 to 2016 in this study. The domain covers the entire tropics between 45°S and 45°N with a spatial resolution of about 45... Version 3.9 of WRF-ARW is run with a tropical belt configuration for a period from 2012 to 2016 in this study. The domain covers the entire tropics between 45°S and 45°N with a spatial resolution of about 45 km. In order to verify two radiation schemes and four cumulus convection schemes, eight experiments are performed with different combinations of physics parameterization schemes. The results show that eight experiments present reasonable spatial patterns of surface air temperature and precipitation in boreal summer, with the spatial correlation coefficient (COR) between simulated and observed temperature exceeding 0.95, and that between simulated and observed precipitation ranges from 0.65 to 0.82. The four experiments with the RRTMG radiation scheme show a better performance than the other four experiments with the CAM radiation scheme. In the four experiments with the RRTMG radiation scheme, the COR between simulated and observed surface air temperature is about 0.98, and that between simulated and observed precipitation ranges from 0.76 to 0.82. Comparatively, the two experiments using the new Tiedtke cumulus parameterization scheme can simulate better diurnal variation of precipitation in boreal summer than the other six experiments. In particular, for the diurnal cycle of precipitation over land and ocean, the experiment using the RRTMG radiation scheme and the new Tiedtke cumulus convection scheme shows that the peaks of precipitation rate appear at 0400 LST and 1600 LST, in agreement with observation. 展开更多
关键词 WRF model cumulus convection parameterization radiation scheme diurnal cycle of precipitation
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Organic and Inorganic Mercury in Biological Samples of Flouresecent Lamp Industries Workers and Health Risks
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作者 Nayab GUL Sardar KHAN +3 位作者 Abbas KHAN Javed NAWAB Adnan SARWAR Nida GUL 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2020年第2期89-102,共14页
Objective The present study aims to investigate the concentrations of Hg and its aspects methyl mercury(Me-Hg)and inorganic mercury(I-Hg)in the biological samples(BSs)of fluorescent lamp industries workers(FLIWs).Meth... Objective The present study aims to investigate the concentrations of Hg and its aspects methyl mercury(Me-Hg)and inorganic mercury(I-Hg)in the biological samples(BSs)of fluorescent lamp industries workers(FLIWs).Methodology Different BSs including red blood cells(RBCs),plasma,urine,hair and nails were collected from the workers exposed to Hg and unexposed persons were selected as control group to measure both the T-Hg concentration as well as its species in different biological samples through quantitative analysis.Health data was collected through questionnaire survey.Results The mean concentrations of T-Hg(31.9μg/L),Me-Hg(27.7μg/L),and I-Hg(5.36μg/L)in RBCs were found significantly(P<0.001)higher among the workers(n=40)as compared to the control group(n=40).Similarly the mean Hg concentrations in plasma,urine,hair and nails were also significantly higher among the workers than the control group.The statistical relation between Hg concentration and demographic characteristics observed that workers experience and fish consumption has increased the Hg concentration while age,weight and smoking found no significant effect on Hg concentration in the BSs.Conclusion The study observed that the workers were highly exposed to high concentration of Hg and they are at a high health risk. 展开更多
关键词 MERCURY Health risk FLUORESCENT LAMP INDUSTRIES Regression DEMOGRAPHIC characteristics Biological SAMPLES
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The relationship between the Arctic Oscillation and ENSO as simulated by CCSM4
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作者 ZHU Yali WANG Tao 《Atmospheric and Oceanic Science Letters》 CSCD 2016年第3期198-203,共6页
The correlation between the Arctic Oscillation (AO) and ENSO reflects the strength of the interaction between climate systems in the low and high latitudes. Based on the long-term (501 years) control simulation of... The correlation between the Arctic Oscillation (AO) and ENSO reflects the strength of the interaction between climate systems in the low and high latitudes. Based on the long-term (501 years) control simulation of CCSM4, the authors investigated the linkage between the AO and ENSO in boreal winter. Based on the correlation coefficients between them, the authors divided the entire period into two groups: one that included the years with statistically significant correlations (G1), and the other the years with insignificant correlations (G2). in G1, the AO-related atmospheric circulation pattern resembles the ENSO-related one. The Aleutian Low (AL) acts as a bridge linking these two modes, in G2, however, the AO and ENSO signals are confined to the mid-high and mid-low latitudes, respectively. There is no significant linkage between the AO and ENSO in boreal winter, showing a low correlation coefficient. Further analysis suggests that changes in the climatological features, including the strengthened AO, the negative Pacific Decadal Oscillation phase, and the weakened AL, may be responsible for the enhanced relationships. 展开更多
关键词 Arctic Oscillation ENSO CCSM4 Aleutian Low climate interaction betweenlow and high latitude
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On a Method of Climatological Observations Processing
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作者 Shamil Iliasov 《Journal of Environmental Science and Engineering(B)》 2013年第12期723-727,共5页
The task of climate observation data processing is central to the quality of an assessment of future climate change impact. The current state-of-the-art is based on the long-running observation records of the meteorol... The task of climate observation data processing is central to the quality of an assessment of future climate change impact. The current state-of-the-art is based on the long-running observation records of the meteorological stations. However, it is common for the developing states to have only relatively short and/or intermittent record histories. The issue becomes even more aggravated under an effort to assess the climatic trends for specific territories with few meteorological stations. The paper offers a simple and effective technique to handle the climate observations; the technique makes the most complete use of an available data set by counting the data provided by all meteorological stations including those with short records and omissions. The method is based on numeric differentiation of source data samples. 展开更多
关键词 Climate change meteorological station OBSERVATION data processing trends.
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Application of Merged Precipitation Estimation Technique to Study Intense Rainfall Events over India and Associated Oceanic Region
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作者 Anoop Kumar Mishra 《Atmospheric and Climate Sciences》 2012年第2期222-229,共8页
In this paper, an effort has been made to study heavy rainfall events during cyclonic storms and active monsoon cycle over Indian land and associated oceanic regions from recently developed merged rainfall technique u... In this paper, an effort has been made to study heavy rainfall events during cyclonic storms and active monsoon cycle over Indian land and associated oceanic regions from recently developed merged rainfall technique using rain gauge and multi-satellite observations from Precipitation Radar (PR) onboard Tropical Rainfall Measuring Mission (TRMM), Special Sensor Microwave Imager (SSMI) onboard Defense Meteorological Satellite Program (DMSP) and Meteosat of Eumetsat. Four recent cyclonic events namely Gonu, Bijli, Aila and Laila were qualitatively analyzed using rainfall from this technique. This technique is validated against another merged rainfall product TRMM-3B42V6 and rain gauge observations during heavy rainfall events of the years 2007, 2008, 2009, 2010. Results presented in this study show that the heavy rainfall events are efficiently monitored by this technique. 展开更多
关键词 PRECIPITATION REMOTE Sensing RADAR
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Spatiotemporal Variation of Benthic Macroinvertebrates in Some Tropical Forest Streams of the Nyong Catchment (Cameroon)
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作者 Jean Dzavi Samuel Foto Menbohan +2 位作者 Blaise Rollinat Mboye Mathias Nwaha Eric Belmond Biram à Ngon 《Open Journal of Applied Sciences》 CAS 2022年第7期1210-1231,共22页
With the aim of assessing the benthic macroinvertebrates’ diversity, a study was carried out in some tropical forest streams of the Nyong River catchment in Cameroon from February 2019 to February 2020. A total of 16... With the aim of assessing the benthic macroinvertebrates’ diversity, a study was carried out in some tropical forest streams of the Nyong River catchment in Cameroon from February 2019 to February 2020. A total of 167 samples were carried out from 13 stations during 13 months. Some environmental variables were measured. These parameters varied more or less from station to station but significantly at the temporal level. In this study, 13,690 benthic macroinvertebrates belonging to 4 phyla, 7 classes, 16 orders and 93 families were collected. The benthic macroinvertebrates were more abundant and more diversified in the stations whose waters are well oxygenated and present a moderate current compared to the stations with a very weak current. The diversity varied significantly from 1.33 ± 0.14 bits/ind to 2.00 ± 0.35 bits/ind and the high values were found in stations with multiple substrates and well-oxygenated waters. Temporally, the diversity varied significantly from 1.10 ± 0.16 bits/ind in NM sampling station in February 2020 to 1.87 ± 0.1 bits/ind in the OB sampling station in September. In addition, the settlement was more abundant during the short dry season, more precisely during the month of August (1471 individuals) but richer during the long dry season during the month of February (54 families). The distribution of the abundances of the benthic fauna in the different stations made it possible to identify five typological groups using the rarefaction curves, the ascending hierarchical classification and the principal component analyses. Each of these five groups is characterized by a specific taxonomic richness, composition and abundance. 展开更多
关键词 Benthic Macroinvertebrates Environmental Variables Faunistic Diversity Taxonomic Richness Biotypology Tropical Forest Streams Cameroon
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The Shift of Traditional Agroecosystems in the in Eastern Arc Catchments of Tanzania
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作者 Agnes G. Kapinga Abimbola Sangodoyin +3 位作者 Olayinka O. Ogunkoya Marko B. Sulley Franco J. Mbegallo Gordon T. Madamombe 《Agricultural Sciences》 2019年第10期1343-1358,共16页
The purpose of this study was to identify the drivers of the shift of traditional agro-ecosystems and their implication on catchment resources management of Eastern Arc Catchments of Tanzania. Lower Mngeta and Upper Z... The purpose of this study was to identify the drivers of the shift of traditional agro-ecosystems and their implication on catchment resources management of Eastern Arc Catchments of Tanzania. Lower Mngeta and Upper Zigi water catchments are situated within Eastern Arc Mountains of Tanzania. Household questionnaire, key informant interviews and focus group discussion were used for collecting primary data. The findings indicated that most of the participants (85.9% and 90.4% in Lower Mngeta and Upper Zigi catchments respectively) depend on subsistence rain-fed agriculture for their livelihoods. However, there are significant changes in production as a result of land fertility deteriorating and negative climatic changes (seasonal shift). This has become a major challenge for most of the farmers. To cope with agro-ecosystem dynamics, farmers in the study areas use both traditional and modern strategies as illustrated in the results section. While tradition always reported to be inexpensive, some modern agro-ecosystem practices reported to cause siltation, killing of fish and herbal plants, easy rotting of seeds (for maize) and bad aroma (for rice)in spite of having a high rate of return. It was also reported that depletion of traditions and norms of conduct, accelerated by multi-cultural interaction from immigrants, have led to deterioration of traditional agriculture practices. Moreover, arrival of agriculture companies and introduction of spice farming was reported to have caused manpower imbalance, unequal distribution of natural resources and less diversity of indigenous plants. The study concludes that communities are much into economic opportunity derived from agro-ecosystem than stewarding it. The study recommends that the effort restoring catchment ecosystem should come from both traditional and modern strategies so as to harmonize and accommodate environmental, economic and traditional values. 展开更多
关键词 AGRO-ECOSYSTEM Culture and DIVERSITY
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Relative contribution of the anthropogenic forcing and natural variability to the interdecadal shift of climate during the late 1970s and 1990s 被引量:5
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作者 Yali Zhu Tao Wang Huijun Wang 《Science Bulletin》 SCIE EI CAS CSCD 2016年第5期416-424,共9页
Global warming accelerated after the late1970 s and slowed down after the late 1990 s, accompanying the significant interdecadal changes in the regional climate.We hypothesized that the interdecadal changes linearly c... Global warming accelerated after the late1970 s and slowed down after the late 1990 s, accompanying the significant interdecadal changes in the regional climate.We hypothesized that the interdecadal changes linearly consisted of two independent components, anthropogenic forcing and natural decadal variability, which can be represented simply by the radiative forcing effect of carbon dioxide (RFCO_2) and the Pacific Decadal Oscillation(PDO), respectively. The combined effect of the RFCO_2 and PDO could explain the majority of the surface temperature changes during the late 1970 s and 1990 s, but the magnitudes of the relative contribution of the RFCO_2 and the PDO are inconsistent in different regions. For both the surface temperature and geopotential height, the RFCO_2 could induce significantly positive anomalies over almost the entire globe for these two shifts, exhibiting a larger magnitude in the mid–high latitudes and in the late 1990 s shift.The PDO could induce opposite anomalies for the two interdecadal shifts due to its phase transitions(negativepositive–negative). Furthermore, for the shift in the late 1970s, both the RFCO2(53.7 %–66.7 %) and the PDO(33.3 %–46.3 %) were important in regulating the tropical geopotential height, whereas the RFCO_2 dominated the changes in the mid-latitudes. For the western Pacific subtropical high, the RFCO2(PDO) could explain 52.3 %–62.1 %(37.9 %–47.7 %) of the change. The negative effect of the PDO counteracted most of the RFCO_2 effects for the late 1990 s shift. 展开更多
关键词 Anthropogenic forcing Natural decadal variability Global warming Surface temperature Geopotential height
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南大洋增暖及其气候影响 被引量:3
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作者 蔡文炬 高立宝 +12 位作者 罗义勇 李熙晨 郑小童 张学斌 程旭华 贾凡 Ariaan Purich Agus Santoso 杜岩 David MHolland 石佳睿 项宝强 谢尚平 《Science Bulletin》 SCIE EI CAS CSCD 2023年第9期946-960,M0004,共16页
过去几十年南大洋在南极平流层臭氧消耗和大气二氧化碳浓度增加的共同作用下大幅增暖,显著影响着南极冰架和冰盖的融化、海平面上升、南北半球的降水分配以及热带海洋和大气环流等,引发了深远的气候效应.全球变暖背景下南大洋西风表现... 过去几十年南大洋在南极平流层臭氧消耗和大气二氧化碳浓度增加的共同作用下大幅增暖,显著影响着南极冰架和冰盖的融化、海平面上升、南北半球的降水分配以及热带海洋和大气环流等,引发了深远的气候效应.全球变暖背景下南大洋西风表现为极向加强,同时进入南大洋的热辐射和淡水通量持续增加,由此上翻的海水可吸收更多的热量和碳,经由更强的平均流向北输送,更多地在45°S附近海域下沉并存储.当前对南大洋增暖背后诸多复杂的物理过程仍缺乏足够的理解,比如来自冰架、冰盖及海洋涡旋的作用、热带-极地相互作用、南大洋本身对全球变暖的响应等,尤其是有限的观测数据和较低分辨率的模式无法准确呈现快速变化的物理现象和机理.因此,南大洋的未来增暖存在很大的不确定性且可能长期持续,但近期的进展为深入认知南大洋增暖及其气候影响奠定了坚实的基础. 展开更多
关键词 平流层臭氧 南大洋 物理现象 物理过程 全球变暖 热带海洋 南北半球 低分辨率
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Estimating Aboveground Carbon Dynamic of China Using Optical and Microwave Remote-Sensing Datasets from 2013 to 2019 被引量:1
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作者 Zhongbing Chang Lei Fan +25 位作者 Jean-Pierre Wigneron Ying-Ping Wang Philippe Ciais Jérôme Chave Rasmus Fensholt Jing MChen Wenping Yuan Weimin Ju Xin Li Fei Jiang Mousong Wu Xiuzhi Chen Yuanwei Qin Frédéric Frappart Xiaojun Li Mengjia Wang Xiangzhuo Liu Xuli Tang Sanaa Hobeichi Mengxiao Yu Mingguo Ma Jianguang Wen Qing Xiao Weiyu Shi Dexin Liu Junhua Yan 《Journal of Remote Sensing》 2023年第1期19-34,共16页
Over the past 2 to 3 decades,Chinese forests are estimated to act as a large carbon sink,yet the magnitude and spatial patterns of this sink differ considerably among studies.Using 3 microwave(L-and X-band vegetation ... Over the past 2 to 3 decades,Chinese forests are estimated to act as a large carbon sink,yet the magnitude and spatial patterns of this sink differ considerably among studies.Using 3 microwave(L-and X-band vegetation optical depth[VOD])and 3 optical(normalized difference vegetation index,leaf area index,and tree cover)remote-sensing vegetation products,this study compared the estimated live woody aboveground biomass carbon(AGC)dynamics over China between 2013 and 2019.Our results showed that tree cover has the highest spatial consistency with 3 published AGC maps(mean correlation value R=0.84),followed by L-VOD(R=0.83),which outperform the other VODs.An AGC estimation model was proposed to combine all indices to estimate the annual AGC dynamics in China during 2013 to 2019.The performance of the AGC estimation model was good(root mean square error=0.05 Pg C and R^(2)=0.90 with a mean relative uncertainty of 9.8% at pixel scale[0.25°]).Results of the AGC estimation model showed that carbon uptake by the forests in China was about+0.17 Pg C year^(-1) from 2013 to 2019.At the regional level,provinces in southwest China including Guizhou(+22.35 Tg C year^(-1)),Sichuan(+14.49 Tg C year^(-1)),and Hunan(+11.42 Tg C year^(-1))provinces had the highest carbon sink rates during 2013 to 2019.Most of the carbon-sink regions have been afforested recently,implying that afforestation and ecological engineering projects have been effective means for carbon sequestration in these regions. 展开更多
关键词 estimation REMOTE MICROWAVE
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气候变化情景下中国因高温造成的劳动生产力损失预估
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作者 程亮亮 谷魁英 +13 位作者 赵亮 王会滨 纪思翰 刘钊 黄建斌 陈艺丹 高学杰 徐影 王灿 罗勇 蔡闻佳 宫鹏 梁万年 黄存瑞 《Science Bulletin》 SCIE EI CAS CSCD 2023年第22期2827-2837,M0006,共12页
气候变化背景下,高温会影响职业人群的工作效率并造成劳动生产力损失.本研究基于区域气候模式并采用本土化的暴露-反应函数,预估了未来气候变化情景下中国因高温造成的劳动时间损失.研究发现,与基线期的213亿小时高温相关劳动时间损失相... 气候变化背景下,高温会影响职业人群的工作效率并造成劳动生产力损失.本研究基于区域气候模式并采用本土化的暴露-反应函数,预估了未来气候变化情景下中国因高温造成的劳动时间损失.研究发现,与基线期的213亿小时高温相关劳动时间损失相比,到21世纪末在RCP2.6、RCP4.5和RCP8.5情景下,损失将分别增加-17.8%、10.8%及121.1%.损失主要集中在华南、华中和华东地区,其中广东与河南将占到全国总损失的四分之一.因为这些区域的温度将更高、人口更密集、户外工作者在总人群中的比例较大.与RCP2.6、RCP4.5和RCP8.5情景相比,若能实现1.5℃温控目标,将分别能够避免11.8%、33.7%和53.9%的劳动时间损失,相当于避免了全中国21世纪中叶的0.1%、0.6%及1.4%的年均GDP损失.本研究显示未来气候变化会给中国造成严重的热相关劳动生产力损失,并强调亟需采取因地制宜的气候减缓及适应策略以保护职业人群健康.本研究对其他与中国相似的发展中国家同样具有重要意义. 展开更多
关键词 Climate change Heat stress LABOR Work hours lost Occupational health
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氮沉降对泥炭地影响的研究进展 被引量:11
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作者 曾竞 卜兆君 +4 位作者 王猛 马进泽 赵红艳 李鸿凯 王升忠 《生态学杂志》 CAS CSCD 北大核心 2013年第2期473-481,共9页
泥炭地是全球碳循环中的重要碳库,其养分贫乏的环境特征、生态过程和生态功能正受到氮沉降的影响。本文从6个方面就氮沉降对泥炭地生态系统的影响予以综述:(1)泥炭地多受氮限制,氮沉降增加土壤氮含量,改变微生物群落组成,促进细菌数量... 泥炭地是全球碳循环中的重要碳库,其养分贫乏的环境特征、生态过程和生态功能正受到氮沉降的影响。本文从6个方面就氮沉降对泥炭地生态系统的影响予以综述:(1)泥炭地多受氮限制,氮沉降增加土壤氮含量,改变微生物群落组成,促进细菌数量的增加,提高微生物酶活性,改变泥炭地的土壤环境;(2)在高氮沉降的泥炭地中,泥炭藓对氮的持留能力、传输能力和耐受能力均降低,造成致毒效应,并最终被喜氮的维管植物代替;(3)氮沉降改变了泥炭地氮贫乏的状况,对植被生产力的影响主要以促进为主;(4)氮沉降增加维管植物氮的供应,促进其生长,而使泥炭藓处于光竞争的劣势地位,改变泥炭藓及其与维管植物的种间关系;(5)氮沉降改变植物体内氮磷比,影响苔藓植物的繁殖与更新,导致泥炭地植被物种组成的变化,甚至引发植被演替;(6)氮沉降通过与泥炭地地上和地下生物组分相互作用,促进泥炭地分解,严重威胁着泥炭地的碳库功能。最后,文章指出了目前泥炭地氮沉降研究中存在的一些问题,为泥炭地氮沉降进一步的研究提供参考。 展开更多
关键词 泥炭藓 碳库 生产力 分解 生物多样性
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Real-time flood forecast and flood alert map over the Huaihe River Basin in China using a coupled hydro-meteorological modeling system 被引量:7
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作者 LIN Charles A. 《Science China(Technological Sciences)》 SCIE EI CAS 2008年第7期1049-1063,共15页
A coupled hydro-meteorological modeling system is established for real-time flood forecast and flood alert over the Huaihe River Basin in China. The system consists of the mesoscale atmospheric model MC2 (Canadian Mes... A coupled hydro-meteorological modeling system is established for real-time flood forecast and flood alert over the Huaihe River Basin in China. The system consists of the mesoscale atmospheric model MC2 (Canadian Mesoscale Compressible Community) that is one-way coupled to the Chinese Xinanjiang distributed hydrological model, a grid-based flow routing model, and a module for acquiring real-time gauge precipitation. The system had been successfully tested in a hindcast mode using 1998 and 2003 flood cases in the basin, and has been running daily in a real-time mode for the summers of 2005 and 2006 over the Wangjiaba sub-basin of the Huaihe River Basin. The MC2 precipitation combined with gauge values is used to drive the Xinanjiang model for hydrograph prediction and production of flood alert map. The performance of the system is illustrated through an examination of real-time flood forecasts for the severe flood case of July 4―15, 2005 over the sub-basin, which was the first and largest flood event encountered to date. The 96-h forecasts of MC2 precipitation are first evaluated using observations from 41 rain gauges over the sub-basin. The forecast hydrograph is then validated with observations at the Wangjiaba outlet of the sub-basin. MC2 precipitation generally compares well with gauge values. The flood peak was predicted well in both timing and intensity in the 96-hour forecast using the combined gauge-MC2 precipitation. The real-time flood alert map can spatially display the propagation of forecast floods over the sub-basin. Our forecast hydrograph was used as opera-tional guidance by the Bureau of Hydrograph, Ministry of Water Resources. Such guidance has been proven very useful for the Office of State Flood Control and Drought Relief Headquarters in operational decision making for flood management. The encouraging results demonstrate the potential of using mesoscale atmospheric model precipitation for real-time flood forecast, which can result in a longer lead time compared to traditional methods. 展开更多
关键词 COUPLED hydro-meteorological modeling system FLOOD forecast FLOOD ALERT MAP MC2
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