Projection of future climate changes and their regional impact is critical for long-term planning at the national and regional levels aimed at adaptation and mitigation. This study assesses the future changes in preci...Projection of future climate changes and their regional impact is critical for long-term planning at the national and regional levels aimed at adaptation and mitigation. This study assesses the future changes in precipitation in China and the associated atmospheric circulation patterns using the Couple Model Intercomparison Project 5 Phase (CMIP5) simulations under the RCP4.5 and RCP8.5 scenarios. The results consistently indicate that the annual precipitation in China is projected to significantly increase at the end of the 21st century compared to the present-day levels. The number of days and the intensity of medium rain, large rain and heavy rain are obviously increased, while the number of trace rain days is projected to decrease over the entire area of China. Further analysis indicates that the significant increase of annual precipitation in Northwest China is primarily due to the increase of light rain and the increases in North and Northeast China are primarily due to the increase of medium rain. In the region of southern China, the increases of large rain and heavy rain play an important role in the increase of annual precipitation, while light rain events play a negative role. Analysis of the changes in atmospheric circulation indicates that the East Asian summer monsoon circulation is projected to be considerably stronger, and the local atmospheric stratification is projected to be more unstable, all of which provide a background benefit for the increase of precipitation and extreme rainfall events in China under global warming scenarios.展开更多
Based on Climatic Research Unit Time Series3.1 temperature and Global Precipitation Climatology Center full data reanalysis version 6 precipitation data,the abilities of climate models from the fifth phase of the Coup...Based on Climatic Research Unit Time Series3.1 temperature and Global Precipitation Climatology Center full data reanalysis version 6 precipitation data,the abilities of climate models from the fifth phase of the Coupled Model Intercomparison Project to simulate climate changes over arid and semiarid areas were assessed.Simulations of future climate changes under different representative concentration pathways(RCPs)were also examined.The key findings were that most of the models are able to capture the dominant features of the spatiotemporal changes in temperature,especially the geographic distribution,during the past 60 years,both globally as well as over arid and semiarid areas.In addition,the models can reproduce the observed warming trends,but with magnitudes generally less than the observations of around0.1–0.3°C/50a.Compared to temperature,the models perform worse in simulating the annual evolution of observed precipitation,underestimating both the variability and tendency,and there is a huge spread among the models in terms of their simulated precipitation results.The multimodel ensemble mean is overall superior to any individual model in reproducing the observed climate changes.In terms of future climate change,an ongoing warming projected by the multi-model ensemble over arid and semiarid areas can clearly be seen under different RCPs,especially under the high emissions scenario(RCP8.5),which is twice that of the moderate scenario(RCP4.5).Unlike the increasing temperature,precipitation changes vary across areas and are more significant under high-emission RCPs,with more precipitation over wet areas but less precipitation over dry areas.In particular,northern China is projected to be one of the typical areas experiencing significantly increased temperature and precipitation in the future.展开更多
An understanding 0f variati0ns in vegetati0n c0ver in resp0nse t0 climate change is critical f0r predicting and managing future terrestrial ec0system dynamics. Because scientists anticipate that m0untain ec0systems wi...An understanding 0f variati0ns in vegetati0n c0ver in resp0nse t0 climate change is critical f0r predicting and managing future terrestrial ec0system dynamics. Because scientists anticipate that m0untain ec0systems will be m0re sensitive t0 future climate change c0mpared t0 0thers, 0ur 0bjectives were t0 investigate the impacts 0f climate change 0n variati0n in vegetati0n c0ver in the Qilian M0untains （QLM）, China, between 2000 and 2011. T0 acc0mplish this, we used linear regressi0n techniques 0n 250-m MODIS N0rmalized Difference Vegetati0n Index （NDVI） datasets and mete0r0l0gical rec0rds t0 determine spati0temp0ral variability in vegetati0n c0ver and climatic fact0rs （i.e. temperature and precipitati0n）. Our results sh0wed that temperatures and precipitati0n have increased in this regi0n during 0ur study peri0d. In additi0n, we f0und that gr0wing seas0n mean NDVI was mainly distributed in the vertical z0ne fr0m 2,700 m t0 3,600 m in elevati0n. In the study regi0n, we 0bserved significant p0sitive and negative trends in vegetati0n c0ver in 26.71% and 2.27% 0f the vegetated areas. C0rrelati0n analyses indicated that rising precipitati0n fr0m May t0 August was resp0nsible f0r increased vegetati0n c0ver in areas with p0sitive trends in gr0wing seas0n mean NDVI. H0wever, there was n0 similar significant c0rrelati0n between gr0wing seas0n mean NDVI and precipitati0n in regi0ns where vegetati0n c0ver declined thr0ugh0ut 0ur study peri0d. Using spatial statistics, we f0und that veeetati0n c0ver freauentlvdeclined in areas within the 2,500-3,100 m vertical z0ne, where it has steep sl0pe, and is 0n the sunny side 0f m0untains. Here, the p0sitive influences 0f increasing precipitati0n c0uld n0t 0ffset the drier c0nditi0ns that 0ccurred thr0ugh warming trends. In c0ntrast, in higher elevati0n z0nes （3,900-4,500 m） 0n the shaded side 0f the m0untains, rising temperatures and increasing precipitati0n impr0ved c0nditi0ns f0r vegetati0n gr0wth. Increased precipitati0n als0 facilitated vegetati0n gr0wth in are展开更多
Using the definition of vulnerability provided by the Intergovernmental Panel on Climate Change,this paper assesses the vulnerability of areas affected by Chinese cryospheric changes from 2001 to 2020 and from 2001 to...Using the definition of vulnerability provided by the Intergovernmental Panel on Climate Change,this paper assesses the vulnerability of areas affected by Chinese cryospheric changes from 2001 to 2020 and from 2001 to 2050 in A1 and B1scenarios.Seven indices are used in the vulnerability assessment:glacial area fraction,interannual variability of permafrost depth,interannual variability of surface snow area fraction,interannual variability of surface runoff,interannual variability of surface temperature,interannual variability of vegetation growth,and interannual variability of the human development index.Assessment results show that the overall vulnerability of the studied areas in China increases from east to west.The areas in the middle and eastern parts of China are less vulnerable compared with western parts and parts of the Tibetan Plateau.The highest vulnerability values are found from 1981 to 2000,and the least ones are found from 2001 to 2050.The vulnerable areas increase from the period of 1981 to 2000 to the period of 2001 to 2050,and the less vulnerable areas decrease.The highly vulnerable areas increase from the period of 1981 to 2000 to the period of 2001 to 2020 and then decrease from the period of 2001 to 2020 to the period of 2001 to 2050.This decrease in vulnerability is attributed to the decrease in exposure and sensitivity to Chinese cryospheric changes along with a concomitant increase in adaptation.展开更多
This study was based on the daily meteorological data of 101 meteorological stations from 1971 to 2000 and the 0.25°×0.25° grid data from 1951 to 2100 simulated by RegCM3 under the future A1B climatic s...This study was based on the daily meteorological data of 101 meteorological stations from 1971 to 2000 and the 0.25°×0.25° grid data from 1951 to 2100 simulated by RegCM3 under the future A1B climatic scenario published by National Climate Center,in combination with the demand of climatic condition for maize growth in Northeast China.The trajectory of agricultural climatic resources and the effects of climate change on variety distribution and climatic potential productivity of spring maize in Northeast China under future climate change were analyzed.The main agro-climatic resource factors include:the initial date daily average temperature stably passing 10℃(≥10℃),the first frost date,the days of growing period,the ≥10℃ accumulated temperature,and the total radiation and precipitation in the growing period.The results showed that:(1) in the coming 100 years,the first date of ≥10℃ would be significantly advanced,and the first frost date would be delayed.The days of growing period would be extended,the ≥10℃ accumulated temperature and the total radiation would be significantly increased.However,no significant change was found in precipitation.(2) Due to the climate change,the early-maturing varieties will be gradually replaced by late-maturing varieties in Northeast China,and the planting boundaries of several maize varieties would be extended northward and eastward.(3) There would be a significant change in the climatic potential productivity of maize in Northeast China with the high-value gradually moving towards northeast.(4) It was an effective way to increase the climatic potential productivity of maize by appropriate adjustment of sowing date.展开更多
Global climate change and its possible ecological consequences have become the focused issue(IPCC,2007;Mann et al.,2008;Ding et al.,2009).The Holocene contains the analogous characteristic of future climatic change an...Global climate change and its possible ecological consequences have become the focused issue(IPCC,2007;Mann et al.,2008;Ding et al.,2009).The Holocene contains the analogous characteristic of future climatic change and the continuous agriculture activity,providing the ideal"similar pattern"for studying the climate change and human adaption and impact in the future.Based on the recent studies of stalagmite,ice core,ocean,and lake etc.,the paper introduces the new progress in the Holocene climate and agriculture research in China as follows:(1)Discuss the variability,amplitude,and unstable characteristic of climate,as well as the abrupt events and mechanisms of climate.(2)Analyze the botanical index records for studying the early agriculture.(3)Review the agricultural origin,expanding,and development.(4)Reveal the style and intensity of early agriculture and understand the agricultural impact and adaption to the environmental changes.(5)Introduce ongoing research projects in China and emphasize the significance of increasing the dating precision and the indicative effectiveness of proxies.(6)Realize how the ecosystem and environmental factors respond to the increasing temperature process,understand how the human adapt to the rapid climate change,and provide the scientific basis for assessing the effects of climate change and the human adaption in the future.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 clima展开更多
The Fourth Assessment Report (AR4) of the Intergovernmental Panel of Climate Change (IPCC) concluded that the climate projection using climate models that took account of both human and natural factors provided credib...The Fourth Assessment Report (AR4) of the Intergovernmental Panel of Climate Change (IPCC) concluded that the climate projection using climate models that took account of both human and natural factors provided credible quantitative estimates of future climate change; however, the mismatches between the IPCC AR4 model ensembles and the observations, especially the multi-decadal variability (MDV), have cast shadows on the confidence of the model-based decadal projections of future cli mate. This paper reports an evaluation of many individual runs of AR4 models in the simulation of past global mean tempera ture. We find that most of the individual model runs fail to reproduce the MDV of past climate, which may have led to the overestimation of the projection of global warming for the next 40 years or so. Based on such an evaluation, we propose an al ternative approach, in which the MDV signal is taken into account, to project the global mean temperature for the next 40 years and obtain that the global warming during 2011–2050 could be much smaller than the AR4 projection.展开更多
Knowledge about climate change impacts on species distribution at national scale is critical to biodi- versity conservation and design of management programs. Although China is a biodiversity hot spot in the world, po...Knowledge about climate change impacts on species distribution at national scale is critical to biodi- versity conservation and design of management programs. Although China is a biodiversity hot spot in the world, potential influence of climate change on Chinese protected birds is rarely studied. Here, we assess the impact of climate change on 108 protected bird species and nature reserves using species distribution modeling at a relatively fine spatial resolution （1 km） for the first time. We found that a large proportion of protected species would have potential suitable habitat shrink and northward range shift by 77-90 km in response to projected future climate change in 2080. Southeastern China would suffer from losing climate suitability, whereas the climate conditions in Qinghai-Tibet Plateau and northeastern China were projected to become suitable for more protected species. On average, each protected area in decline of suitable climate for China would experience a 3-4 species by 2080. Cli- mate change will modify which species each protected area will be suitable for. Our results showed that the risk of extinction for Chinese protected birds would be high, even in the moderate climate change scenario. These findings indicate that the management and design of nature reserves in China must take climate change into consideration.展开更多
Climate-induced drought has exerted obvious impacts on land systems in northern China.Although recent reports by the Intergovernmental Panel on Climate Change(IPCC) have suggested a high possibility of climate-induced...Climate-induced drought has exerted obvious impacts on land systems in northern China.Although recent reports by the Intergovernmental Panel on Climate Change(IPCC) have suggested a high possibility of climate-induced drought in northern China,the potential impacts of such drying trends on land systems are still unclear.Land use models are powerful tools for assessing the impacts of future climate change.In this study,we first developed a land use scenario dynamic model(iLUSD) by integrating system dynamics and cellular automata.Then,we designed three drying trend scenarios(reversed drying trend,gradual drying trend,and acceleration of drying trend) for the next 25 years based on the IPCC emission scenarios and considering regional climatic predictions in northern China.Finally,the impacts of drying trend scenarios on the land system were simulated and compared.An accuracy assessment with historic data covering 2000 to 2005 indicated that the developed model is competent and reliable for understanding complex changes in the land use system.The results showed that water resources varied from 441.64 to 330.71 billion m3 among different drying trend scenarios,suggesting that future drying trends will have a significant influence on water resource and socioeconomic development.Under the pressures of climate change,water scarcity,and socioeconomic development,the ecotone(i.e.,transition zone between cropping area and nomadic area) in northern China will become increasingly vulnerable and hotspots for land-use change.Urban land and grassland would have the most prominent response to the drying trends.Urban land will expand around major metropolitan areas and the conflict between urban and cultivated land will become more severe.The results also show that previous ecological control measures adopted by the government in these areas will play an important role in rehabilitating the environment.In order to achieve a sustainable development in northern China,issues need to be addressed such as how to arrange land use struc展开更多
基金supported by the National Basic Research Program of China (2012CB955401)the "Strategic Priority Research Program-Climate Change: Carbon Budget and Relevant Issues" of the Chinese Academy of Sciences (XDA05090306)+1 种基金the National Natural Science Foundation of China (41275075)the CAS-CSIRO Cooperative Research Program (GJHZ1223)
文摘Projection of future climate changes and their regional impact is critical for long-term planning at the national and regional levels aimed at adaptation and mitigation. This study assesses the future changes in precipitation in China and the associated atmospheric circulation patterns using the Couple Model Intercomparison Project 5 Phase (CMIP5) simulations under the RCP4.5 and RCP8.5 scenarios. The results consistently indicate that the annual precipitation in China is projected to significantly increase at the end of the 21st century compared to the present-day levels. The number of days and the intensity of medium rain, large rain and heavy rain are obviously increased, while the number of trace rain days is projected to decrease over the entire area of China. Further analysis indicates that the significant increase of annual precipitation in Northwest China is primarily due to the increase of light rain and the increases in North and Northeast China are primarily due to the increase of medium rain. In the region of southern China, the increases of large rain and heavy rain play an important role in the increase of annual precipitation, while light rain events play a negative role. Analysis of the changes in atmospheric circulation indicates that the East Asian summer monsoon circulation is projected to be considerably stronger, and the local atmospheric stratification is projected to be more unstable, all of which provide a background benefit for the increase of precipitation and extreme rainfall events in China under global warming scenarios.
基金supported by the National Basic Research Program of China(2012CB956203)the China Meteorological Administration R&D Special Fund for Public Welfare(Meteorology)(GYHY201006023)the National Key Technologies R&D Program of China(2012BAC22B04)
文摘Based on Climatic Research Unit Time Series3.1 temperature and Global Precipitation Climatology Center full data reanalysis version 6 precipitation data,the abilities of climate models from the fifth phase of the Coupled Model Intercomparison Project to simulate climate changes over arid and semiarid areas were assessed.Simulations of future climate changes under different representative concentration pathways(RCPs)were also examined.The key findings were that most of the models are able to capture the dominant features of the spatiotemporal changes in temperature,especially the geographic distribution,during the past 60 years,both globally as well as over arid and semiarid areas.In addition,the models can reproduce the observed warming trends,but with magnitudes generally less than the observations of around0.1–0.3°C/50a.Compared to temperature,the models perform worse in simulating the annual evolution of observed precipitation,underestimating both the variability and tendency,and there is a huge spread among the models in terms of their simulated precipitation results.The multimodel ensemble mean is overall superior to any individual model in reproducing the observed climate changes.In terms of future climate change,an ongoing warming projected by the multi-model ensemble over arid and semiarid areas can clearly be seen under different RCPs,especially under the high emissions scenario(RCP8.5),which is twice that of the moderate scenario(RCP4.5).Unlike the increasing temperature,precipitation changes vary across areas and are more significant under high-emission RCPs,with more precipitation over wet areas but less precipitation over dry areas.In particular,northern China is projected to be one of the typical areas experiencing significantly increased temperature and precipitation in the future.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41271024, 40871057, J1210065)
文摘An understanding 0f variati0ns in vegetati0n c0ver in resp0nse t0 climate change is critical f0r predicting and managing future terrestrial ec0system dynamics. Because scientists anticipate that m0untain ec0systems will be m0re sensitive t0 future climate change c0mpared t0 0thers, 0ur 0bjectives were t0 investigate the impacts 0f climate change 0n variati0n in vegetati0n c0ver in the Qilian M0untains （QLM）, China, between 2000 and 2011. T0 acc0mplish this, we used linear regressi0n techniques 0n 250-m MODIS N0rmalized Difference Vegetati0n Index （NDVI） datasets and mete0r0l0gical rec0rds t0 determine spati0temp0ral variability in vegetati0n c0ver and climatic fact0rs （i.e. temperature and precipitati0n）. Our results sh0wed that temperatures and precipitati0n have increased in this regi0n during 0ur study peri0d. In additi0n, we f0und that gr0wing seas0n mean NDVI was mainly distributed in the vertical z0ne fr0m 2,700 m t0 3,600 m in elevati0n. In the study regi0n, we 0bserved significant p0sitive and negative trends in vegetati0n c0ver in 26.71% and 2.27% 0f the vegetated areas. C0rrelati0n analyses indicated that rising precipitati0n fr0m May t0 August was resp0nsible f0r increased vegetati0n c0ver in areas with p0sitive trends in gr0wing seas0n mean NDVI. H0wever, there was n0 similar significant c0rrelati0n between gr0wing seas0n mean NDVI and precipitati0n in regi0ns where vegetati0n c0ver declined thr0ugh0ut 0ur study peri0d. Using spatial statistics, we f0und that veeetati0n c0ver freauentlvdeclined in areas within the 2,500-3,100 m vertical z0ne, where it has steep sl0pe, and is 0n the sunny side 0f m0untains. Here, the p0sitive influences 0f increasing precipitati0n c0uld n0t 0ffset the drier c0nditi0ns that 0ccurred thr0ugh warming trends. In c0ntrast, in higher elevati0n z0nes （3,900-4,500 m） 0n the shaded side 0f the m0untains, rising temperatures and increasing precipitati0n impr0ved c0nditi0ns f0r vegetati0n gr0wth. Increased precipitati0n als0 facilitated vegetati0n gr0wth in are
基金supported by the National Basic Research Program of China (2007CB411507)
文摘Using the definition of vulnerability provided by the Intergovernmental Panel on Climate Change,this paper assesses the vulnerability of areas affected by Chinese cryospheric changes from 2001 to 2020 and from 2001 to 2050 in A1 and B1scenarios.Seven indices are used in the vulnerability assessment:glacial area fraction,interannual variability of permafrost depth,interannual variability of surface snow area fraction,interannual variability of surface runoff,interannual variability of surface temperature,interannual variability of vegetation growth,and interannual variability of the human development index.Assessment results show that the overall vulnerability of the studied areas in China increases from east to west.The areas in the middle and eastern parts of China are less vulnerable compared with western parts and parts of the Tibetan Plateau.The highest vulnerability values are found from 1981 to 2000,and the least ones are found from 2001 to 2050.The vulnerable areas increase from the period of 1981 to 2000 to the period of 2001 to 2050,and the less vulnerable areas decrease.The highly vulnerable areas increase from the period of 1981 to 2000 to the period of 2001 to 2020 and then decrease from the period of 2001 to 2020 to the period of 2001 to 2050.This decrease in vulnerability is attributed to the decrease in exposure and sensitivity to Chinese cryospheric changes along with a concomitant increase in adaptation.
基金supported by the Research and Development Special Fundfor Public Welfare Industry (Meteorology) (GYHY201106020)
文摘This study was based on the daily meteorological data of 101 meteorological stations from 1971 to 2000 and the 0.25°×0.25° grid data from 1951 to 2100 simulated by RegCM3 under the future A1B climatic scenario published by National Climate Center,in combination with the demand of climatic condition for maize growth in Northeast China.The trajectory of agricultural climatic resources and the effects of climate change on variety distribution and climatic potential productivity of spring maize in Northeast China under future climate change were analyzed.The main agro-climatic resource factors include:the initial date daily average temperature stably passing 10℃(≥10℃),the first frost date,the days of growing period,the ≥10℃ accumulated temperature,and the total radiation and precipitation in the growing period.The results showed that:(1) in the coming 100 years,the first date of ≥10℃ would be significantly advanced,and the first frost date would be delayed.The days of growing period would be extended,the ≥10℃ accumulated temperature and the total radiation would be significantly increased.However,no significant change was found in precipitation.(2) Due to the climate change,the early-maturing varieties will be gradually replaced by late-maturing varieties in Northeast China,and the planting boundaries of several maize varieties would be extended northward and eastward.(3) There would be a significant change in the climatic potential productivity of maize in Northeast China with the high-value gradually moving towards northeast.(4) It was an effective way to increase the climatic potential productivity of maize by appropriate adjustment of sowing date.
基金supported by the CAS Strategic Priority Research Program(Grant No.XDA01020304)National Natural Science Foundation of China(Grant No.41172161)National Basic Research Program of China(Grant No.2010CB950204)
文摘Global climate change and its possible ecological consequences have become the focused issue(IPCC,2007;Mann et al.,2008;Ding et al.,2009).The Holocene contains the analogous characteristic of future climatic change and the continuous agriculture activity,providing the ideal"similar pattern"for studying the climate change and human adaption and impact in the future.Based on the recent studies of stalagmite,ice core,ocean,and lake etc.,the paper introduces the new progress in the Holocene climate and agriculture research in China as follows:(1)Discuss the variability,amplitude,and unstable characteristic of climate,as well as the abrupt events and mechanisms of climate.(2)Analyze the botanical index records for studying the early agriculture.(3)Review the agricultural origin,expanding,and development.(4)Reveal the style and intensity of early agriculture and understand the agricultural impact and adaption to the environmental changes.(5)Introduce ongoing research projects in China and emphasize the significance of increasing the dating precision and the indicative effectiveness of proxies.(6)Realize how the ecosystem and environmental factors respond to the increasing temperature process,understand how the human adapt to the rapid climate change,and provide the scientific basis for assessing the effects of climate change and the human adaption in the future.
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 clima
基金supported by the National Basic Research Program of Chi-na (Grant No. 2011CB952000)the National Natural Science Founda-tion of China (Grant No. 40810059003)+1 种基金Qian Cheng was partly supported by the "Strategic Priority Research Program" of the Chinese Academy of Sciences (Grant No. XDA05090103)Wu Zhaohua was supported by the Natural Science Foundation of USA (Grant No. ATM-0917743)
文摘The Fourth Assessment Report (AR4) of the Intergovernmental Panel of Climate Change (IPCC) concluded that the climate projection using climate models that took account of both human and natural factors provided credible quantitative estimates of future climate change; however, the mismatches between the IPCC AR4 model ensembles and the observations, especially the multi-decadal variability (MDV), have cast shadows on the confidence of the model-based decadal projections of future cli mate. This paper reports an evaluation of many individual runs of AR4 models in the simulation of past global mean tempera ture. We find that most of the individual model runs fail to reproduce the MDV of past climate, which may have led to the overestimation of the projection of global warming for the next 40 years or so. Based on such an evaluation, we propose an al ternative approach, in which the MDV signal is taken into account, to project the global mean temperature for the next 40 years and obtain that the global warming during 2011–2050 could be much smaller than the AR4 projection.
基金supported by the National High Technology Research and Development Program of China(‘‘863’’Program)(2009AA12200101)the National Natural Science Foundation of China(41471347)
文摘Knowledge about climate change impacts on species distribution at national scale is critical to biodi- versity conservation and design of management programs. Although China is a biodiversity hot spot in the world, potential influence of climate change on Chinese protected birds is rarely studied. Here, we assess the impact of climate change on 108 protected bird species and nature reserves using species distribution modeling at a relatively fine spatial resolution （1 km） for the first time. We found that a large proportion of protected species would have potential suitable habitat shrink and northward range shift by 77-90 km in response to projected future climate change in 2080. Southeastern China would suffer from losing climate suitability, whereas the climate conditions in Qinghai-Tibet Plateau and northeastern China were projected to become suitable for more protected species. On average, each protected area in decline of suitable climate for China would experience a 3-4 species by 2080. Cli- mate change will modify which species each protected area will be suitable for. Our results showed that the risk of extinction for Chinese protected birds would be high, even in the moderate climate change scenario. These findings indicate that the management and design of nature reserves in China must take climate change into consideration.
基金supported by the National Basic Research Program of China(Grant Nos.2010CB950901&2014CB954300)the National Natural Science Foundation of China(Grant No.41222003)the State Key Laboratory of Earth Surface Processes and Resource Ecology(Grant No.2013-RC-03)
文摘Climate-induced drought has exerted obvious impacts on land systems in northern China.Although recent reports by the Intergovernmental Panel on Climate Change(IPCC) have suggested a high possibility of climate-induced drought in northern China,the potential impacts of such drying trends on land systems are still unclear.Land use models are powerful tools for assessing the impacts of future climate change.In this study,we first developed a land use scenario dynamic model(iLUSD) by integrating system dynamics and cellular automata.Then,we designed three drying trend scenarios(reversed drying trend,gradual drying trend,and acceleration of drying trend) for the next 25 years based on the IPCC emission scenarios and considering regional climatic predictions in northern China.Finally,the impacts of drying trend scenarios on the land system were simulated and compared.An accuracy assessment with historic data covering 2000 to 2005 indicated that the developed model is competent and reliable for understanding complex changes in the land use system.The results showed that water resources varied from 441.64 to 330.71 billion m3 among different drying trend scenarios,suggesting that future drying trends will have a significant influence on water resource and socioeconomic development.Under the pressures of climate change,water scarcity,and socioeconomic development,the ecotone(i.e.,transition zone between cropping area and nomadic area) in northern China will become increasingly vulnerable and hotspots for land-use change.Urban land and grassland would have the most prominent response to the drying trends.Urban land will expand around major metropolitan areas and the conflict between urban and cultivated land will become more severe.The results also show that previous ecological control measures adopted by the government in these areas will play an important role in rehabilitating the environment.In order to achieve a sustainable development in northern China,issues need to be addressed such as how to arrange land use struc
