On the basis of NOAA/CPC data of sea surface temperature anomaly in the Nifio regions during Jan. 1950 - Dec. 2003, the wavelet power spectrum of SST were studied with significance and confidence testing at different ...On the basis of NOAA/CPC data of sea surface temperature anomaly in the Nifio regions during Jan. 1950 - Dec. 2003, the wavelet power spectrum of SST were studied with significance and confidence testing at different scales in this paper. It shows that the SST are provided with multi-time scales structure nested one another, and vary on scales of 2 - 7 years, 8 - 20 years and 〉30 years. The most significant variation of the warm and cold episodes is in the 4-year band of period. The power, frequency structure and confidence of the same episode are different in different Nino regions. The intensity of oscillations is increasing at low frequency bands and decreasing at high frequency bands from east to west in the Nino regions, especially after 1970.展开更多
This paper analyzes the air pollution situation in China,particularly the severe intensifying tendency in central North China.Five major comments on the air pollution issue in China are proposed,emphasizing the scient...This paper analyzes the air pollution situation in China,particularly the severe intensifying tendency in central North China.Five major comments on the air pollution issue in China are proposed,emphasizing the scientific understanding on the mechanisms of air pollution formation processes,the interannual variability,the relative roles of climate change and pollutant emissions,the interaction between climate change and atmospheric chemical processes,and the seasonal prediction of air pollution.The viewpoints have significance for air pollution management in China and around the world.展开更多
Although paid to upward shift response to global phenomenon at low zones did not receive increasing attention has been of plant species in altitude as a warming, research on this altitudinal and low latitudinal enoug...Although paid to upward shift response to global phenomenon at low zones did not receive increasing attention has been of plant species in altitude as a warming, research on this altitudinal and low latitudinal enough attention. In this study, an investigation was carried out to test the relationship between the upward spread of Moso bamboo (Phyllostachys pubescens) along altitudinal gradient and the increasing air temperature over the past decade within the Tianmu Mountain region, situated in southeastern China. Results showed that the peak elevation of Moso bamboo population establishment rose by an average of 9.8 m (±2.7 m) during the past decade and significant correlation existed with mean annual temperature (P 〈 0.0001, n = 339) but not with annual precipitation (P = 0.7, n = 339), indicating that the upward shift of Moso bamboo along altitudinal gradients was driven primarily by warming temperatures. This upward shift could potentially reduce biodiversity by altering the species composition of the ecosystem. However, there is also the potential for increased carbon sequestration capacity of local forest systems, which would produce an additional carbon sink to combat rising atmospheric C02 concentrations and future global warming.展开更多
Many countries are developing national strategies and action plans aimed at minimising the negative impacts of climate change on biodiversity.The purpose of this paper is to provide a brief overview not only of strate...Many countries are developing national strategies and action plans aimed at minimising the negative impacts of climate change on biodiversity.The purpose of this paper is to provide a brief overview not only of strategies and plans that have been developed in Australia,but also of research that has been carried out in Australia by the Commonwealth Scientific and Industrial Research Organisation(CSIRO) Climate Adaptation Flagship to assist the development of future strategies and plans.Major points are summarised from key policy documents such as the National Biodiversity and Climate Change Action Plan 2004-2007,and Australia's Biodiversity Conservation Strategy 2010-2030,as well as the 2009 report on "Australia's Biodiversity and Climate Change".Within the first three years of its existence,the Natural Ecosystems theme in CSIRO Climate Adaptation Flagship has carried out studies analysing impacts and identifying potential adaptations across the whole of Australia's vast terrestrial and marine environments.Techniques used in these studies could be applied easily in other countries and could assist the development of more effective national strategies and adaptation action plans for the conservation of biodiversity under climate change.展开更多
This study examined the rainfall around the middle and lower reaches of the Yangtze River and related atmospheric circulation by using NCEP reanalysis data. The purpose of this study is to analyze their decadal variat...This study examined the rainfall around the middle and lower reaches of the Yangtze River and related atmospheric circulation by using NCEP reanalysis data. The purpose of this study is to analyze their decadal variation and the relationship among rainfall, atmospheric circulation around East Asia and the ENSO episodes. Current results are presented as follows: (1) Very clear increasing trend of the rainfall around the middle and low reaches of the Yangtze River during the Meiyu period and June to July is found in the recent 15 years. Meanwhile, the geopotential height at 500 hPa around the Okhotsk Sea also holds similar increasing trend. It is noticeable that ENSO episodes tend to occur more frequently in the recent 15 years. (2) An index describing East Asian summer monsoon is well correlated with the SST in the Nino-3 region in preceding autumn in the recent 20 years but is not prior to the period. This means that the El Nino phenomenon exerts more impacts on East Asian summer monsoon recently. (3) The warm phase of PDO in the recent 20 years basically coincides with the increasing trend of the atmospheric circulation in East Asia.展开更多
Diyala River is the third largest tributary of the Tigris River running 445 km length and draining an area of 32,600 km2. The river is the major source of water supply for Diyala City for municipal, domestic, agricult...Diyala River is the third largest tributary of the Tigris River running 445 km length and draining an area of 32,600 km2. The river is the major source of water supply for Diyala City for municipal, domestic, agriculture and other purposes. Diyala River Basin currently is suffering from water scarcity and contamination problems. Up-to-date studies have shown that blue and green waters of a basin have been demonstrating increasing variability contributing to more severe droughts and floods seemingly due to climate change. To obtain better understanding of the impacts of climate change on water resources in Diyala River Basin in near 2046-2064 and distant future 2080~2100, SWAT (soil and water assessment tool) was used. The model is first examined for its capability of capturing the basin characteristics, and then, projections from six GCMs (general circulation models) are incorporated to assess the impacts of climate change on water resources under three emission scenarios: A2, AIB and B1. The results showed deteriorating water resources regime into the future.展开更多
Evaluation of the mean climate and climate variability in the Southern Hemisphere (SH) in the Twentieth Century Reanalysis data version 2 (20CRv2) is conducted and the results are compared with the NCEP/NCAR versi...Evaluation of the mean climate and climate variability in the Southern Hemisphere (SH) in the Twentieth Century Reanalysis data version 2 (20CRv2) is conducted and the results are compared with the NCEP/NCAR version 2 Reanalysis data (NCEPv2) and the Hadley Center sea-level pressure data (HadSLPv2).The results show that SH polar High,SH subtropical High,upper level split jet,cross-equatorial flow,Antarctic Oscillation (AAO),and the pattem of Pacific-South-America (PSA) has been effectively captured by 20CRv2 during 1979-2010,with an apparent zonal asymmetry of AAO in the austral winter (June-July-August,JJA).The notable upward linear trend of AAO in the entire period of 1871-2010 is represented in both 20CRv2 and HadS1Pv2.The most remarkable discrepancy of the SH climate variability between 20CRv2 and HadSLPv2 occurred in 1897-1920 and was partly caused by such factors as the paucity of meteorological and oceanographic data in the SH to be assimilated,the handling of the specified sea-ice concentration in South Pole,and imperfect climate models.The consistency of these reanalysis data is increased with the use of a large amount of satellite observation and radiosonde data,particularly after 1979.展开更多
This research deals with an evaluation of the sink of greenhouse gas CO2 in a eutrophic area of the Venetian lagoon where fish is farmed ("Valle da pesca"). Following CDM UNFCCC (Clean Development Mechanism Unite...This research deals with an evaluation of the sink of greenhouse gas CO2 in a eutrophic area of the Venetian lagoon where fish is farmed ("Valle da pesca"). Following CDM UNFCCC (Clean Development Mechanism United Nations Framework Convention on Climate Change) criteria, this can be considered relevant to the international standard for the voluntary evaluation of carbon credits on the basis of Annex a of Kyoto Protocol. To identify the "Valle da pesca" brackish lagoon properties regulating the carbon dioxide (CO2), a survey has been performed during three seasons in one year and in four different locations. These places are located in the Italian Venetian Lagoon and in the Grado Lagoon in North Italy, Europe. To identify the CO2 sink capacity, a special index is calculated. The CO2 concentrations and sink are regulated by the balance of autotrophic and heterotrophic activities, and the sediment anoxic denitrification and macro algae are crucial tank of CO2 in the valley shallow waters. The ponds potential-CO2 yield of 80-124 kg/m2 per year and the value are related and proportional to the correct human environmental control (water flux control).展开更多
Greater Zab is the largest tributary of the Tigris River in lraq where the catchment area is currently being plagued by water scarcity and pollution problems. Contemporary studies have revealed that blue and green wat...Greater Zab is the largest tributary of the Tigris River in lraq where the catchment area is currently being plagued by water scarcity and pollution problems. Contemporary studies have revealed that blue and green waters of the basin have been manifesting increasing variability contributing to more severe droughts and floods apparently due to climate change. In order to gain greater appreciation of the impacts of climate change on water resources in the study area in near and distant future, SWAT (Soil and Water Assessment Tool) has been used. The model is first tested for its suitability in capturing the basin characteristics, and then, forecasts from six GCMs (general circulation models) with about half-a-century lead time to 2046-2064 and one-century lead time to 2080-2100 are incorporated to evaluate the impacts of climate change on water resources under three emission scenarios: A 1 B, A2 and BI. The results showed worsening water resources regime into the future.展开更多
Examining the direct and indirect effects of climatic factors on vegetation growth is critical to understand the complex linkage between climate change and vegetation dynamics. Based on the Moderate Resolution Imaging...Examining the direct and indirect effects of climatic factors on vegetation growth is critical to understand the complex linkage between climate change and vegetation dynamics. Based on the Moderate Resolution Imaging Spectroradiometer(MODIS) Normalized Difference Vegetation Index(NDVI) data and meteorological data(temperature and precipitation) from 2001 to 2012, the trend of vegetation dynamics were examined in the Ziya-Daqing basins, China. The path analysis was used to obtain the information on the relationships among climatic factors and their effects on vegetation growth. It was found that the trends of growing season NDVI were insignificant in most plain dry land, while the upward trends were significant in forest, grass and dry land in Taihang Mountains. According to the path analysis, in 23% of the basins the inter-annual NDVI variation was dominated by the direct effect of precipitation, in 5% by the direct effects of precipitation and temperature, and in less than 1% by the direct effect of temperature or indirect effects of these two climatic factors. It indicated that precipitation significantly affected the vegetation growth in the whole basins, and this effect was not regulated by temperature. Precipitation increase(especially in July, August and September) was favorable to greenness enhancement. Summer temperature rising showed negative effect on plant productivity enhancement, but temperature rise in April was beneficial for the vegetation growth. When April temperature increases by 1℃, the onset date of greenness for natural vegetation will be 2 days in advance. There was a lag-time effect of precipitation or temperature on monthly NDVI for all land use types except grass.展开更多
In this study,the relationship between the North Atlantic Oscillation (NAO) in winter (DecemberFebruary) and the precipitation over southem China (SCP) in the following spring (March-May) was investigated.Resu...In this study,the relationship between the North Atlantic Oscillation (NAO) in winter (DecemberFebruary) and the precipitation over southem China (SCP) in the following spring (March-May) was investigated.Results showed an interdecadal change,from strong to weak connection,in their connection.Before the early 1980s,they were highly correlated,with a strong (weak) winter NAO followed by an increased (decreased) spring SCP.However,after the early 1980s,their relationship was weakened significantly.This unstable relationship may be linked to the climatological change of East Asian jet.Before the early 1980s,the wave train along the Asian jet propagated the NAO signal eastward to East Asia and affected local upper-tropospheric atmospheric circulation.A strong NAO in winter led to an anomalous anticyclonic circulation at the south side of 30°N in East Asia in spring,resulting in an increase of SCP.In contrast,after the early 1980s,the wave train pattern along the Asian jet extended eastward due to strengthening of the climatological East Asian jet.Correspondingly,the NAO-related East Asian atmospheric circulations in the upper troposphere shifted eastward,thereby weakening the linkage between the spring SCP and the winter NAO.展开更多
In this secondary research, published works on effect of climate change on water resources in other countries and in Australia were reviewed critically. Research question, objectives and assumptions were made to facil...In this secondary research, published works on effect of climate change on water resources in other countries and in Australia were reviewed critically. Research question, objectives and assumptions were made to facilitate this study. First, methods used for such studies and their results at global level were reviewed. Then Australian specific methods of study and findings were reviewed. More commonly, both globally and in Australia, simulations using long-term real data on selected climatic scenarios of global climatic models are projected for long-term future trends. The validity and certainty of predicted occurrences depend upon the closeness of real time data with scenarios to which they are projected. Even with these limitations, projections of already rising temperatures and declining rainfall on surface water and ground water availabilities show gradual decline in water availability leading to water stress both for human communities and ecosystems The role of human-induced emissions in hastening the degradation process has also been investigated. Conserving all available water, practising efficient water consumption and prudent water policies only can provide some relief from what is inevitable.展开更多
This paper reviews the studies and research on climate change impacts on the forest ecosystems in Northeast China. The results show that in the context of global and regional warming, the growing season of coniferous ...This paper reviews the studies and research on climate change impacts on the forest ecosystems in Northeast China. The results show that in the context of global and regional warming, the growing season of coniferous forests has been increasing at an average rate of 3.9 d per decade. Regional warming favors the growth of temperate broad-leaved forests and has a detrimental effect on the growth of boreal coniferous forests. Over the past hundred years, the forest edge of the cool temperate zone in the southern Daxing'anling region has retreated 140 km northward. From 1896 to 1986, the northern boundary of broad-leaved forests in Heilongjiang province has extended northwestward about 290 km. Future climatic changes (until 2060) may lead to the northern deciduous needle forests moving out of China's territory altogether. The occurrence cycles of pests and diseases have shortened; their distribution ranges have expanded. The life cycle of tent caterpillars (Malacosoma neustria testacea Motschulsky) has shortened from 14-15 years in the past to 8-10 years now. The pine caterpillar (Dendrolimus tabulaeformis Tsai et Liu), which has spread within western Liaoning province and the nearby areas, can now be found in the north and west. Lightning fires in the Daxing'anling region have significantly increased since 1987, and August has become the month when lightning fires occur most frequently. Overall, the net primary productivity (NPP) of forest in Northeast China has increased. The NPP in 1981 was around 0.27 Pg C, and increased to approximately 0.40 Pg C in 2002. With the current climate, the broad-leaved Korean pine forest ecosystem acts as a carbon sink, with a carbon sink capacity of 2.7 Mg C hm-2. Although the carbon sink capacity of the forest ecosystems in Northeast China has been weakened since 2003, the total carbon absorption will still increase. The forest ecosystems in Northeast China are likely to remain a significant carbon sink, and will play a positive role in the mitigation of climate change.展开更多
Over the past few decades,an increasing number of marine activities have been conducted in the East China Sea,including the construction of various marine structures and the passage of large ships.Marine safety issues...Over the past few decades,an increasing number of marine activities have been conducted in the East China Sea,including the construction of various marine structures and the passage of large ships.Marine safety issues are paramount and are becoming more important with respect to the likely increase in size of ocean waves in relation to global climate change and associated typhoons.In addition,swells also can be very dangerous because they induce the resonance of floating structures,including ships.This study focuses on an investigation of swells in the East China Sea and uses hindcast data for waves over the past 5 years in a numerical model,WAVEWATCH III(WW3),together with historical climate data.The numerical calculation domain covers the entire North West Pacific.Next,swells are separated and analyzed using simulated wave fields,and both the characteristics and generation mechanisms of swells are investigated.展开更多
This paper investigates the influence of Indian Ocean Dipole (IOD) on climatic variations over East Asian monsoon region, based on CAS IAP AGCM-Ⅱduring Equatorial East Pacific Ocean SSTA or not. The results show that...This paper investigates the influence of Indian Ocean Dipole (IOD) on climatic variations over East Asian monsoon region, based on CAS IAP AGCM-Ⅱduring Equatorial East Pacific Ocean SSTA or not. The results show that the southwest monsoon over East Asian will break out later than normal, the intensity of the summer monsoon over the South China Sea (SCS) is stronger than normal, and more rainfall on Chinese main land is simulated when only IOD forcing exists. With both IOD and Equatorial East Pacific Ocean SSTA forcing, the southwest monsoon will break out much later than normal, the intensity of the SCS summer monsoon also is weaker than normal, and less rainfall in North China is simulated. Therefore, Equatorial East Pacific Ocean SSTA and IOD have a synergic effect.展开更多
This paper examines the distribution and structure of populations of a medicinal and culinary herb native to Armenia. As one of the first countries to join the Convention on Biological Diversity (CBD), Armenia has a...This paper examines the distribution and structure of populations of a medicinal and culinary herb native to Armenia. As one of the first countries to join the Convention on Biological Diversity (CBD), Armenia has a strong interest in assessing the biodiversity of its native flora and identifying threats to the conservation of these species, particularly those with economic value. Only limited information, however, is available at this time on the genetic biodiversity, population location, structure and size, and conservation status of most of these species. This paper reports the results of five consecutive years of field studies conducted in Armenia to 1) re-locate native populations of the important medicinal and culinary herb, Origanum vulgare L., 2) locate new populations, and 3) assess the growth pattern and dynamics of the populations. The quadrat sampling technique was used to identify key elements that determined population size and abundance. GPS maps of present and past population distributions were created. Particular habitat and environmental factors were identified as crucial to predicting the future conditions of these populations under the impact of global climate change. The research provides a baseline dataset that can be used for the development of further conservation strategies of this important medicinal and culinary species in Armenia.展开更多
文摘On the basis of NOAA/CPC data of sea surface temperature anomaly in the Nifio regions during Jan. 1950 - Dec. 2003, the wavelet power spectrum of SST were studied with significance and confidence testing at different scales in this paper. It shows that the SST are provided with multi-time scales structure nested one another, and vary on scales of 2 - 7 years, 8 - 20 years and 〉30 years. The most significant variation of the warm and cold episodes is in the 4-year band of period. The power, frequency structure and confidence of the same episode are different in different Nino regions. The intensity of oscillations is increasing at low frequency bands and decreasing at high frequency bands from east to west in the Nino regions, especially after 1970.
基金supported by the National Natural Science Foundation of China[grant number 41421004]the National Key Research and Development Program of China[grant number 2016YFA0600704]
文摘This paper analyzes the air pollution situation in China,particularly the severe intensifying tendency in central North China.Five major comments on the air pollution issue in China are proposed,emphasizing the scientific understanding on the mechanisms of air pollution formation processes,the interannual variability,the relative roles of climate change and pollutant emissions,the interaction between climate change and atmospheric chemical processes,and the seasonal prediction of air pollution.The viewpoints have significance for air pollution management in China and around the world.
基金funded by the National Nature Science Foundation of China (Grant No. 31070440,31270517)China QianRen Program,NSERC-Discovery GrantZhejiang A & F University Research and Development Fund (2012FR023)
文摘Although paid to upward shift response to global phenomenon at low zones did not receive increasing attention has been of plant species in altitude as a warming, research on this altitudinal and low latitudinal enough attention. In this study, an investigation was carried out to test the relationship between the upward spread of Moso bamboo (Phyllostachys pubescens) along altitudinal gradient and the increasing air temperature over the past decade within the Tianmu Mountain region, situated in southeastern China. Results showed that the peak elevation of Moso bamboo population establishment rose by an average of 9.8 m (±2.7 m) during the past decade and significant correlation existed with mean annual temperature (P 〈 0.0001, n = 339) but not with annual precipitation (P = 0.7, n = 339), indicating that the upward shift of Moso bamboo along altitudinal gradients was driven primarily by warming temperatures. This upward shift could potentially reduce biodiversity by altering the species composition of the ecosystem. However, there is also the potential for increased carbon sequestration capacity of local forest systems, which would produce an additional carbon sink to combat rising atmospheric C02 concentrations and future global warming.
文摘Many countries are developing national strategies and action plans aimed at minimising the negative impacts of climate change on biodiversity.The purpose of this paper is to provide a brief overview not only of strategies and plans that have been developed in Australia,but also of research that has been carried out in Australia by the Commonwealth Scientific and Industrial Research Organisation(CSIRO) Climate Adaptation Flagship to assist the development of future strategies and plans.Major points are summarised from key policy documents such as the National Biodiversity and Climate Change Action Plan 2004-2007,and Australia's Biodiversity Conservation Strategy 2010-2030,as well as the 2009 report on "Australia's Biodiversity and Climate Change".Within the first three years of its existence,the Natural Ecosystems theme in CSIRO Climate Adaptation Flagship has carried out studies analysing impacts and identifying potential adaptations across the whole of Australia's vast terrestrial and marine environments.Techniques used in these studies could be applied easily in other countries and could assist the development of more effective national strategies and adaptation action plans for the conservation of biodiversity under climate change.
基金Research Fund for Tropical Oceans Project 973 of the Ministry of Science and Technology(2004CB418300) No. 2002DIB20067 from the Ministry of Science and Technology.
文摘This study examined the rainfall around the middle and lower reaches of the Yangtze River and related atmospheric circulation by using NCEP reanalysis data. The purpose of this study is to analyze their decadal variation and the relationship among rainfall, atmospheric circulation around East Asia and the ENSO episodes. Current results are presented as follows: (1) Very clear increasing trend of the rainfall around the middle and low reaches of the Yangtze River during the Meiyu period and June to July is found in the recent 15 years. Meanwhile, the geopotential height at 500 hPa around the Okhotsk Sea also holds similar increasing trend. It is noticeable that ENSO episodes tend to occur more frequently in the recent 15 years. (2) An index describing East Asian summer monsoon is well correlated with the SST in the Nino-3 region in preceding autumn in the recent 20 years but is not prior to the period. This means that the El Nino phenomenon exerts more impacts on East Asian summer monsoon recently. (3) The warm phase of PDO in the recent 20 years basically coincides with the increasing trend of the atmospheric circulation in East Asia.
文摘Diyala River is the third largest tributary of the Tigris River running 445 km length and draining an area of 32,600 km2. The river is the major source of water supply for Diyala City for municipal, domestic, agriculture and other purposes. Diyala River Basin currently is suffering from water scarcity and contamination problems. Up-to-date studies have shown that blue and green waters of a basin have been demonstrating increasing variability contributing to more severe droughts and floods seemingly due to climate change. To obtain better understanding of the impacts of climate change on water resources in Diyala River Basin in near 2046-2064 and distant future 2080~2100, SWAT (soil and water assessment tool) was used. The model is first examined for its capability of capturing the basin characteristics, and then, projections from six GCMs (general circulation models) are incorporated to assess the impacts of climate change on water resources under three emission scenarios: A2, AIB and B1. The results showed deteriorating water resources regime into the future.
基金supported by the Strategic Technological Program of the Chinese Academy of Sciences(Grant No.XDA05090426)the National Basic Research Program of China(Grant No.2010CB950304)the Key Program of the Chinese Academy of Sciences(Grant KZCX2-YW-QN202)
文摘Evaluation of the mean climate and climate variability in the Southern Hemisphere (SH) in the Twentieth Century Reanalysis data version 2 (20CRv2) is conducted and the results are compared with the NCEP/NCAR version 2 Reanalysis data (NCEPv2) and the Hadley Center sea-level pressure data (HadSLPv2).The results show that SH polar High,SH subtropical High,upper level split jet,cross-equatorial flow,Antarctic Oscillation (AAO),and the pattem of Pacific-South-America (PSA) has been effectively captured by 20CRv2 during 1979-2010,with an apparent zonal asymmetry of AAO in the austral winter (June-July-August,JJA).The notable upward linear trend of AAO in the entire period of 1871-2010 is represented in both 20CRv2 and HadS1Pv2.The most remarkable discrepancy of the SH climate variability between 20CRv2 and HadSLPv2 occurred in 1897-1920 and was partly caused by such factors as the paucity of meteorological and oceanographic data in the SH to be assimilated,the handling of the specified sea-ice concentration in South Pole,and imperfect climate models.The consistency of these reanalysis data is increased with the use of a large amount of satellite observation and radiosonde data,particularly after 1979.
文摘This research deals with an evaluation of the sink of greenhouse gas CO2 in a eutrophic area of the Venetian lagoon where fish is farmed ("Valle da pesca"). Following CDM UNFCCC (Clean Development Mechanism United Nations Framework Convention on Climate Change) criteria, this can be considered relevant to the international standard for the voluntary evaluation of carbon credits on the basis of Annex a of Kyoto Protocol. To identify the "Valle da pesca" brackish lagoon properties regulating the carbon dioxide (CO2), a survey has been performed during three seasons in one year and in four different locations. These places are located in the Italian Venetian Lagoon and in the Grado Lagoon in North Italy, Europe. To identify the CO2 sink capacity, a special index is calculated. The CO2 concentrations and sink are regulated by the balance of autotrophic and heterotrophic activities, and the sediment anoxic denitrification and macro algae are crucial tank of CO2 in the valley shallow waters. The ponds potential-CO2 yield of 80-124 kg/m2 per year and the value are related and proportional to the correct human environmental control (water flux control).
文摘Greater Zab is the largest tributary of the Tigris River in lraq where the catchment area is currently being plagued by water scarcity and pollution problems. Contemporary studies have revealed that blue and green waters of the basin have been manifesting increasing variability contributing to more severe droughts and floods apparently due to climate change. In order to gain greater appreciation of the impacts of climate change on water resources in the study area in near and distant future, SWAT (Soil and Water Assessment Tool) has been used. The model is first tested for its suitability in capturing the basin characteristics, and then, forecasts from six GCMs (general circulation models) with about half-a-century lead time to 2046-2064 and one-century lead time to 2080-2100 are incorporated to evaluate the impacts of climate change on water resources under three emission scenarios: A 1 B, A2 and BI. The results showed worsening water resources regime into the future.
基金Under the auspices of National Natural Science Foundation of China(No.41471026,31171451)Strategic Science and Technology Program in the Thirteenth Five-Year Plan of Institute of Geographical Sciences and Natural Resources Research,Chinese Academy of Sciences(No.2012ZD003)
文摘Examining the direct and indirect effects of climatic factors on vegetation growth is critical to understand the complex linkage between climate change and vegetation dynamics. Based on the Moderate Resolution Imaging Spectroradiometer(MODIS) Normalized Difference Vegetation Index(NDVI) data and meteorological data(temperature and precipitation) from 2001 to 2012, the trend of vegetation dynamics were examined in the Ziya-Daqing basins, China. The path analysis was used to obtain the information on the relationships among climatic factors and their effects on vegetation growth. It was found that the trends of growing season NDVI were insignificant in most plain dry land, while the upward trends were significant in forest, grass and dry land in Taihang Mountains. According to the path analysis, in 23% of the basins the inter-annual NDVI variation was dominated by the direct effect of precipitation, in 5% by the direct effects of precipitation and temperature, and in less than 1% by the direct effect of temperature or indirect effects of these two climatic factors. It indicated that precipitation significantly affected the vegetation growth in the whole basins, and this effect was not regulated by temperature. Precipitation increase(especially in July, August and September) was favorable to greenness enhancement. Summer temperature rising showed negative effect on plant productivity enhancement, but temperature rise in April was beneficial for the vegetation growth. When April temperature increases by 1℃, the onset date of greenness for natural vegetation will be 2 days in advance. There was a lag-time effect of precipitation or temperature on monthly NDVI for all land use types except grass.
基金supported by the Special Fund for Public Welfare Industry (Meteorology) (GYHY201306026)the National Natural Science Foundation of China (41275078)the National Basic Research Program of China (2009CB421407)
文摘In this study,the relationship between the North Atlantic Oscillation (NAO) in winter (DecemberFebruary) and the precipitation over southem China (SCP) in the following spring (March-May) was investigated.Results showed an interdecadal change,from strong to weak connection,in their connection.Before the early 1980s,they were highly correlated,with a strong (weak) winter NAO followed by an increased (decreased) spring SCP.However,after the early 1980s,their relationship was weakened significantly.This unstable relationship may be linked to the climatological change of East Asian jet.Before the early 1980s,the wave train along the Asian jet propagated the NAO signal eastward to East Asia and affected local upper-tropospheric atmospheric circulation.A strong NAO in winter led to an anomalous anticyclonic circulation at the south side of 30°N in East Asia in spring,resulting in an increase of SCP.In contrast,after the early 1980s,the wave train pattern along the Asian jet extended eastward due to strengthening of the climatological East Asian jet.Correspondingly,the NAO-related East Asian atmospheric circulations in the upper troposphere shifted eastward,thereby weakening the linkage between the spring SCP and the winter NAO.
文摘In this secondary research, published works on effect of climate change on water resources in other countries and in Australia were reviewed critically. Research question, objectives and assumptions were made to facilitate this study. First, methods used for such studies and their results at global level were reviewed. Then Australian specific methods of study and findings were reviewed. More commonly, both globally and in Australia, simulations using long-term real data on selected climatic scenarios of global climatic models are projected for long-term future trends. The validity and certainty of predicted occurrences depend upon the closeness of real time data with scenarios to which they are projected. Even with these limitations, projections of already rising temperatures and declining rainfall on surface water and ground water availabilities show gradual decline in water availability leading to water stress both for human communities and ecosystems The role of human-induced emissions in hastening the degradation process has also been investigated. Conserving all available water, practising efficient water consumption and prudent water policies only can provide some relief from what is inevitable.
基金the Public Research Institute Fun-damental Research Foundation of the Institute of Atmospheric Environment of ChinaChina Meteororlgical Administration(No.2011IAE-CMA01)+1 种基金National Natural Science Foundation of China(No.41171199)the Special Climate Change Research Program Foundation of China Meteororlgical Administration(No.062700s010c01)for providing supports
文摘This paper reviews the studies and research on climate change impacts on the forest ecosystems in Northeast China. The results show that in the context of global and regional warming, the growing season of coniferous forests has been increasing at an average rate of 3.9 d per decade. Regional warming favors the growth of temperate broad-leaved forests and has a detrimental effect on the growth of boreal coniferous forests. Over the past hundred years, the forest edge of the cool temperate zone in the southern Daxing'anling region has retreated 140 km northward. From 1896 to 1986, the northern boundary of broad-leaved forests in Heilongjiang province has extended northwestward about 290 km. Future climatic changes (until 2060) may lead to the northern deciduous needle forests moving out of China's territory altogether. The occurrence cycles of pests and diseases have shortened; their distribution ranges have expanded. The life cycle of tent caterpillars (Malacosoma neustria testacea Motschulsky) has shortened from 14-15 years in the past to 8-10 years now. The pine caterpillar (Dendrolimus tabulaeformis Tsai et Liu), which has spread within western Liaoning province and the nearby areas, can now be found in the north and west. Lightning fires in the Daxing'anling region have significantly increased since 1987, and August has become the month when lightning fires occur most frequently. Overall, the net primary productivity (NPP) of forest in Northeast China has increased. The NPP in 1981 was around 0.27 Pg C, and increased to approximately 0.40 Pg C in 2002. With the current climate, the broad-leaved Korean pine forest ecosystem acts as a carbon sink, with a carbon sink capacity of 2.7 Mg C hm-2. Although the carbon sink capacity of the forest ecosystems in Northeast China has been weakened since 2003, the total carbon absorption will still increase. The forest ecosystems in Northeast China are likely to remain a significant carbon sink, and will play a positive role in the mitigation of climate change.
基金funded by the National Natural Science Fundation of China(Nos.51579091,51379071,and 51137002)the National Science Fund for Distinguished Young Scholars(No.51425901)+3 种基金the Qing Lan Project of Jiangsu Provincethe Basic Research Fund from State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University(Nos.20145027512 and 20145028412)the Short-term Research Visits project supported by Disaster Prevention Research Institute of Kyoto University(No.27S-02)the Fundamental Research Funds for the Central Universities of Hohai University(No.2016B05214)
文摘Over the past few decades,an increasing number of marine activities have been conducted in the East China Sea,including the construction of various marine structures and the passage of large ships.Marine safety issues are paramount and are becoming more important with respect to the likely increase in size of ocean waves in relation to global climate change and associated typhoons.In addition,swells also can be very dangerous because they induce the resonance of floating structures,including ships.This study focuses on an investigation of swells in the East China Sea and uses hindcast data for waves over the past 5 years in a numerical model,WAVEWATCH III(WW3),together with historical climate data.The numerical calculation domain covers the entire North West Pacific.Next,swells are separated and analyzed using simulated wave fields,and both the characteristics and generation mechanisms of swells are investigated.
基金National key fundamental research development program "Research of formation mechanism and forecast theory about fatal climatic calamity of China" (G1998040900).
文摘This paper investigates the influence of Indian Ocean Dipole (IOD) on climatic variations over East Asian monsoon region, based on CAS IAP AGCM-Ⅱduring Equatorial East Pacific Ocean SSTA or not. The results show that the southwest monsoon over East Asian will break out later than normal, the intensity of the summer monsoon over the South China Sea (SCS) is stronger than normal, and more rainfall on Chinese main land is simulated when only IOD forcing exists. With both IOD and Equatorial East Pacific Ocean SSTA forcing, the southwest monsoon will break out much later than normal, the intensity of the SCS summer monsoon also is weaker than normal, and less rainfall in North China is simulated. Therefore, Equatorial East Pacific Ocean SSTA and IOD have a synergic effect.
文摘This paper examines the distribution and structure of populations of a medicinal and culinary herb native to Armenia. As one of the first countries to join the Convention on Biological Diversity (CBD), Armenia has a strong interest in assessing the biodiversity of its native flora and identifying threats to the conservation of these species, particularly those with economic value. Only limited information, however, is available at this time on the genetic biodiversity, population location, structure and size, and conservation status of most of these species. This paper reports the results of five consecutive years of field studies conducted in Armenia to 1) re-locate native populations of the important medicinal and culinary herb, Origanum vulgare L., 2) locate new populations, and 3) assess the growth pattern and dynamics of the populations. The quadrat sampling technique was used to identify key elements that determined population size and abundance. GPS maps of present and past population distributions were created. Particular habitat and environmental factors were identified as crucial to predicting the future conditions of these populations under the impact of global climate change. The research provides a baseline dataset that can be used for the development of further conservation strategies of this important medicinal and culinary species in Armenia.