The Pearl River Delta(PRD)region has been identified as a significant hotspot of wet ammonium deposition.However,the absence of long-term monitoring data in the area hinders the comprehension of the historical trends ...The Pearl River Delta(PRD)region has been identified as a significant hotspot of wet ammonium deposition.However,the absence of long-term monitoring data in the area hinders the comprehension of the historical trends and changes in wet NH_(4)^(+)-N deposition in response to emissions,which interferes with the ability to make effective decisions.This study has analyzed the long-term trends of wet NH_(4)^(+)-N deposition flux and has quantified the effect of anthropogenic emissions and meteorological factors at a typical urban site and a typical forest site in the PRD region from 2009 to 2020.It revealed a significant decreasing trend in wet NH_(4)^(+)-N flux in both the typical urban and forest areas of the PRD region,at-6.2%/year(p<0.001)and-3.3%/year(p<0.001),respectively.Anthropogenic emissions are thought to have contributed 47%–57%of the wet NH_(4)^(+)-N deposition trend over the past 12 years compared to meteorological factors.Meteorological conditions dominated the interannual fluctuations in wet NH_(4)^(+)-N deposition with an absolute contribution of 46%–52%,while anthropogenic emissions change alone explained 10%–31%.NH_(3)emissions have the greatest impact on the urban area among anthropogenic emission factors,while SO_(2)emissions have the greatest impact on the forest area.Additionally,precipitation was identified as the primary meteorological driver for both sites.Our findings also imply that the benefits of NH_(3)emissions reductions might not immediately emerge due to interference from weather-related factors.展开更多
Three global datasets, the History Database of the Global Environment （HYDE）, Kaplan and Krurnhardt （KK） and Pongratz of reconstructed anthropogenic land cover change （ALCC） were introduced and compared in this ...Three global datasets, the History Database of the Global Environment （HYDE）, Kaplan and Krurnhardt （KK） and Pongratz of reconstructed anthropogenic land cover change （ALCC） were introduced and compared in this paper. The HYDE dataset was recon- structed by Goldewijk and his colleagues at the National institute of Public ttealth and the Environment in Netherland, covering the past 12 000 years. The KK dataset was reconstructed by Kaplan and his colleagues, the Soil-Vegetation-Atmosphere Research Group at the Institute of Environmental Engineering in Switzerland, covering the past 8000 years. The Pongratz dataset was reconstructed by Pon- gratz and her colleagues at the Max Planck Institute for Meteorology in Germany, coveting AD 800-1992. The results show that the reconstructed datasets are quite different from each other due to the different methods used. The three datasets all allocated the historical ALCC according to human population density. The main reason causing the differences among the three datasets lies on the different relationships between population density and land use used in each reconstructed dataset. The KK dataset is better than the other two datasets for two important reasons. First, it used the nonlinear relationship between population density and land use, while the other two used the linear relationship. Second, Kaplan and his colleagues adopted the technological development and intensification parameters and considered the wood harvesting and the long-term fallow area resulted from shifting cultivation, which were neglected in the recon- structions of the other two datasets. Therefore, the KK dataset is more suitable as one of the anthropogenic forcing fields for climate simulation over the past two millennia that is recently concerned by two projects, the National Basic Research Program and the Strategic and Special Frontier Project of Science and Technology of the Chinese Academy of Sciences.展开更多
Today anthropogenic climate change is underway and predicted future global temperatures vary significantly. However, the drivers of current climate change and their links to Earth’s natural glacial cycle have yet to ...Today anthropogenic climate change is underway and predicted future global temperatures vary significantly. However, the drivers of current climate change and their links to Earth’s natural glacial cycle have yet to be fully resolved. Currently, many on a local level understand, and are exposed to, the heat energy generated by what’s referred to as the urban heat island effect (UHI), whereby natural flora with higher albedos </span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">is</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> replaced by manmade urban areas with lower albedos. This heat effect is not constrained to these regions and all anthropogenic surfaces with lower albedos need to be studied and quantified as the accumulated additional heat energy (infrared energy) is trapped within Earth’s atmosphere and could affect the Earth on a planetary level. Deployed satellites have detected critical changes to Earth’s albedo to lower levels, however the cause and impact of these changes have yet to be fully understood and incorporated into Global Circulation models (GCMs). Here it’s shown that industrialization of anthropogenic landscape practices of the past century has displaced millions of square kilometres of naturally high albedo grasslands with lower albedo agricultural landscapes. Utilising a fundamental Energy Balance Model, (EBM) it’s demonstrated these specific changes have generated vast amounts of additional heat energy which is trapped by the atmosphere, transferred and stored within the oceans of the Earth as shown in <b></span></span></span><a href="file:///E:/360data/%E9%87%8D%E8%A6%81%E6%95%B0%E6%8D%AE/%E6%A1%8C%E9%9D%A2/%E7%A9%BA%E7%99%BD%E9%A1%B5.docx#F1"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">Figure 1</span></b></span></span></a><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"></b></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">. The total additional heat energy accumulated over the preceding 110 years correlates to that required to warm the Earth to the levels seen to date, altering Earth’s overall energy budget. This energy will continue to accumulate and warm the Earth to a predicted 1.60 ± 0.20 Celsius by 2050 over 1910 levels. These findings are independent of anthropogenic Greenhouse Gas (GHG) additions and are further validated by predicting Earth’s temperature and albedo at the last glacial maxima, suggesting that an albedo cycle aligned to Gaia theory is the primary driver of Earth’s natural climate cycle.展开更多
Efforts to restore urban rivers require an understanding of human-influenced changes in channel substrates. This study uses three naturally-occurring oxbows in a 3.5 km reach of Swan Creek, flowing through the City of...Efforts to restore urban rivers require an understanding of human-influenced changes in channel substrates. This study uses three naturally-occurring oxbows in a 3.5 km reach of Swan Creek, flowing through the City of Toledo, Ohio (USA) to reconstruct historical changes in channel substrate. Human impacts in the watershed were: 1) land clearance for agriculture (peaking in 1900-1920) and for suburban housing tracts (peaking in 1945-1970), followed by 2) the post-1940 creation of more efficient urban run-off systems from streets, parking lots, housing developments, and shopping centers. Historical aerial photographs and maps from 1935, 1940, 1950, 1963, 1974, and 1994 were georeferenced using ground control points, input to ArcGIS, and have root mean square error (RMSE) ranging from 0.19 - 0.77 m (average RMSE = 0.47 ± 0.20 m) when compared to the 2006 digital ortho quarter-quadrangle (DOQQ) image used as the basis for comparison. Results showed that channel sinuosity continually increased from 1.88 (1935) to 1.99 (2006). Two oxbows probably formed in 1913, and the third formed in 1940. Sediment cores and trenches were used to recognize historical channel substrates. Age control was provided by <sup>14</sup>C geochronology and labels on food packaging materials found in flood layers. Grain-size analysis of channel substrates shows a historical coarsening-upward trend: the largest clast size interval (f<sub>5</sub>) changes from +0.78f in pre-1935 channels, to -1.15f in pre-1940 channels, to -1.69f in the 2006 channel. These results indicate recent urban runoff created fluvial pavements and increasing channel mobility as the stream removes legacy sediment from intrabasinal sediment storage.展开更多
Climate changes are one of the most significant aspects, which cause a threat to all human beings living on the planet Earth. Climate changes could happen due to both natural internal processes and external forcing, o...Climate changes are one of the most significant aspects, which cause a threat to all human beings living on the planet Earth. Climate changes could happen due to both natural internal processes and external forcing, or due to persistent anthropogenic changes. The identified drastic temperature changes, increase in the emitted greenhouse gasses, and sea-level changes as witnessed from the acquired data;such as from ice cores, during the past centuries and even decades are all due to climate changes. Due to the increase in the emitted greenhouse gasses, major sectors in the Earth will be hit severely, such as agriculture and industry. Human welfare and health services will consequently suffer and development, in general, is going to be hampered. Large parts of the Earth will be unfavorable for living due to different reasons;such as inundation by seawater, decrease in temperature;however, some scientists believe that the increase in the percentages of the emitted greenhouse gasses has decreased or delayed the possibility of starting a new ice age. We have presented all possible scenarios, which may happen due to climate changes including temperature changes, emitted greenhouse gasses, sea level, and other harsh effects not only on human beings but all other living animal and plant species.展开更多
In recent years, intensifying waterlogging, salt water intrusion, wetland loss, and ecosystem degradation in Chinese delta cities and adjacent regions have generated the pressing need to create an urban form that is s...In recent years, intensifying waterlogging, salt water intrusion, wetland loss, and ecosystem degradation in Chinese delta cities and adjacent regions have generated the pressing need to create an urban form that is suited to both current and future climates incorporating sea level rise. However, adaptation planning uptake is slow. This is particularly unfortunate because patterns of urban form interact with mean sea level rise （MSLR） in ways that reduce or intensify its impact. There are currently two main barriers that are significant in arresting the implementation of adaptation planning with reference to the MSLR projections composed of geomorphologic MSLR projections and eustatic MSLR projections from global climate warming, and making a comprehensive risk assessment of MSLR projections. The present review shows recent progresses in mapping MSLR projections and their risk assessment approaches on Chinese delta cities, and then a perspective of adapting these cities to MSLR projections as following six aspects. 1） The geomorphologic MSLR projections are contributed by the natural tectonic subsidence projections and the MSLR projections by anthropogenic geomorphologic change. The former needs to be updated in a global framework. The latter is accumulated by land subsidence from underground water depletion, water level fall caused by the erosion of riverbeds from a sediment supply decline attributed to the construction of watershed dams, artificial sand excavation, water level raise by engineering projects including land reclamation, deep waterway regulation, and fresh water reservoirs. 2） Controlling MSLR projections by anthropogenic geomorphologic changes. 3） The IPCC AR5 RCPs MSLRs scenarios are expected to be projected to the local eustatic MSLR projections on the Chinese deltas. 4） The MSLR projections need to be matched to a local elevation datum. 5） Modeling approaches of regional river-sea numerical with semi- analytical hydrodynamics, estuarine channel network, system dynamics and adaptation points are perspective. 6） Adaptation planning to MSLR projections requires a comprehensive risk assessment of the risk of flood, fresh water supply shortage, coastal erosion, wetland loss, siltation of ports and waterway in Chinese delta cities and adjacent regions.展开更多
Coastal regions are becoming increasingly vulnerable to flooding because of accelerating sea-level-rise(SLR),local ground subsidence,and the changes in topography and morphology.Moreover,coastal areas are usually high...Coastal regions are becoming increasingly vulnerable to flooding because of accelerating sea-level-rise(SLR),local ground subsidence,and the changes in topography and morphology.Moreover,coastal areas are usually highly urbanized and increased human activities have an effect on the stability and preservation of the environment.For instance,the growing demand for new lands to accommodate the population and the industrial facilities in China has required the design and the deployment of land-reclamation projects from the ocean,with a marked impact on fragile coastal eco-systems.Specifically,the Yangtze River and Pearl River Estuary,two major estuaries of the world,have long been subject to intensive human activities over the past decades.Long-term ground subsidence evolution,topographic changes,and morphological variation of the coastal regions have drawn great attention.This paper provides an overview of well-established Earth Observation(EO)remote sensing(RS)technologies that are employed to continuously monitor the changes of urbanized regions.The combined use of EO-based DInSAR analyses along with the knowledge of the geomorphology of the coastal regions allows a more precise picture of the SLR risk in the investigated coastal regions.In this paper,we will concentrate on remote sensing technologies that allow the gathering of heterogeneous information,such as those based on the use of synthetic aperture radar(SAR),satellite altimeters and tide gauge data.We will underline how human activities trigger changes in the living environment of coastal zones and the associated risks for the population.Observed coastline changes,coastal regions terrain subsidence,and offshore bathymetry have a pronounced effect on the increasing risk of flooding.Accordingly,we also present insights into some inundation model projections employed for evaluating the potential flooding risk in coastal regions.展开更多
In this paper the authors perform an extensive sensitivity analysis of the Indian summer monsoon rainfall to changes in parameters and boundary conditions which are influenced by human activities. For this study the a...In this paper the authors perform an extensive sensitivity analysis of the Indian summer monsoon rainfall to changes in parameters and boundary conditions which are influenced by human activities. For this study the authors use a box model of the Indian monsoon which reproduces key features of the observed monsoon dynamics such as the annual course of precipitation and the transitions between winter and summer regimes. Because of its transparency and computational efficiency, this model is highly suitable for exploring the effects of anthropogenic perturbations such as emissions of greenhouse gases and sulfur dioxide, and land cover changes, on the Indian monsoon. Results of a systematic sensitivity analysis indicate that changes in those parameters which are related to emissions of greenhouse gases lead to an increase in Indian summer rainfall. In contrast, all parameters related to higher atmospheric aerosol concentrations lead to a decrease in Indian rainfall. Similarly, changes in parameters which can be related to forest conversion or desertifieation, act to decrease the summer precipitation. The results indicate that the sign of precipitation changes over India will be dependent on the direction and relative magnitude of different human perturbations.展开更多
Understanding the role of anthropogenic forcings in regional hydrological changes can help communities plan their adaptation in an informed manner.Here we apply attribution research methods to investigate the effect o...Understanding the role of anthropogenic forcings in regional hydrological changes can help communities plan their adaptation in an informed manner.Here we apply attribution research methods to investigate the effect of human influence on historical trends in wet and dry summers and changes in the likelihood of extreme events in Europe.We employ an ensemble of new climate models and compare experiments with and without the effect of human influence to assess the anthropogenic contribution.Future changes are also analysed with projections to year 2100.We employ two drought indices defined relative to the pre-industrial climate:one driven by changes in rainfall only and one that also includes the effect of temperature via changes in potential evapotranspiration.Both indices suggest significant changes in European summers have already emerged above variability and are expected to intensify in the future,leading to widespread dryer conditions which are more extreme in the south.When only the effect of rainfall is considered,there is a distinct contrast between a shift towards wetter conditions in the north and dryer in the south of the continent,as well as an overall increase in variability.However,when the effect of warming is also included,it largely masks the wet trends in the north,resulting in increasingly drier summers across most of the continent.Historical index trends are already detected in the observations,while models suggest that what were extremely dry conditions in the pre-industrial climate will become normal in the south by the end of the century.展开更多
Journal of Mountain Science(JMS)is a monthly peer-reviewed scientific journal covering research on natural and anthropogenic environmental changes and sustainable development in mountain areas.JMS is sponsored by Inst...Journal of Mountain Science(JMS)is a monthly peer-reviewed scientific journal covering research on natural and anthropogenic environmental changes and sustainable development in mountain areas.JMS is sponsored by Institute of Mountain Hazards and Environment,Chinese Academy of Sciences,supervised by Chinese Academy of Sciences,and published by Science Press and Springer Nature.JMS was launched in 2004 and indexed by SCI in 2007.JMS has a distinctly international character,with editorial board members and scientific editors from over 30 countries(regions)and international organizations,and authors and reviewers from more than 100 countries and regions.展开更多
There have been considerable high-impact extreme events occurring around the world in the context of climate change.Event attribution studies,which seek to quantitatively answer whether and to what extent anthropogeni...There have been considerable high-impact extreme events occurring around the world in the context of climate change.Event attribution studies,which seek to quantitatively answer whether and to what extent anthropogenic climate change has altered the characteristics-predominantly the probability and magnitude-of particular events,have been gaining increasing interest within the research community.This paper reviews the latest approaches used in event attribution studies through a new classification into three major categories according to how the event attribution question is framed-namely,the risk-based approach,the storyline approach,and the combined approach.Four approaches in the risk-based framing category and three in the storyline framing category are also reviewed in detail.The advantages and disadvantages of each approach are discussed.Particular attention is paid to the ability,suitability,and applicability of these approaches in attributing extreme events in China,a typical monsoonal region where climate models may not perform well.Most of these approaches are applicable in China,and some are more suitable for analyzing temperature events.There is no right or wrong among these approaches,but different approaches have different framings.The uncertainties in attribution results come from several aspects,including different categories of framing,different conditions in climate model approaches,different models,different definitions of the event,and different observational data used.Clarification of these aspects can help to understand the differences in attribution results from different studies.展开更多
Survival and successful reproduction require animals to make critical decisions amidst a naturally dynamic environmental and social background(i.e.“context”).However,human activities have pervasively,and rapidly,ext...Survival and successful reproduction require animals to make critical decisions amidst a naturally dynamic environmental and social background(i.e.“context”).However,human activities have pervasively,and rapidly,extended contextual variation into evolutionarily novel territory,potentially rendering evolved animal decision-making mechanisms and strategies maladaptive.We suggest that explicitly focusing on animal decision-making(ADM),by integrating and applying findings from studies of sensory ecology,cognitive psychology,behavioral economics and eco-evolutionary strategies,may enhance our understanding of,and our ability to predict how,human-driven changes in the environment and population demography will influence animal populations.Fundamentally,the decisions animals make involve evolved mechanisms,and behaviors emerge from the combined action of sensory integration,cognitive mechanisms and strategic rules of thumb,and any of these processes may have a disproportionate influence on behavior.Although there is extensive literature exploring ADM,it generally reflects a canalized,discipline-specific approach that lacks a unified conceptual framework.As a result,there has been limited application of ADM theory and research findings into predictive models that can enhance management outcomes,even though it is likely that the relative resilience of species to rapid environmental change is fundamentally a result of how ADM is linked to contextual variation.Here,we focus on how context influences ADM,and highlight ideas and results that may be most applicable to conservation biology.展开更多
Aims Annually variable but synchronous production of large seed crops(‘masting’)is a widespread phenomenon in temperate trees.Mounting concerns about the impacts of anthropogenic climate change(ACC)on plant reproduc...Aims Annually variable but synchronous production of large seed crops(‘masting’)is a widespread phenomenon in temperate trees.Mounting concerns about the impacts of anthropogenic climate change(ACC)on plant reproduction gives urgency to our need to understand better the role of climate on tree reproduction,and in particular,mast events.Unlike our understanding of reproductive phenology however,there is little consensus regarding how climate affects plant reproductive effort or indeed the actual environmental triggers that underpin masting behaviour.Methods We used a 27-year record of acorn yield from a population of 12 Quercus robur trees located in southern England to compare mast-ing frequency and post-dispersal acorn yield each year for each tree,with long-term weather data over the same period.We focussed on discrete or sequential climate cues(temperature,precipitation and frost days)as likely predictors of oak reproduction.Important Findings Annual post-dispersal acorn crop varied greatly;i.e.no acorns in 14 of the 27 years,but there was no sequential pattern of crop ver-sus non-crop years indicating that weather,rather than resource limitation alone,dictated the timing of reproduction.Crop years were instead most closely associated with relatively cool late sum-mer conditions in the preceding year,followed by anomalous sum-mer warmth within crop year.Acorn yield increased following dry April and above-average May and June temperatures within crop year.Although our results support a general association between warm late spring and summer conditions,and crop frequency and yield,respectively,the influence of cooler later summer conditions in the year prior to masting highlights how a combination of weather cues may dictate the occurrence of mast years.Consequently,our results corroborate not only the hypothesis that temperature differ-entials between consecutive years,not absolute temperatures,may be the better predictor of mast seeding events but lend support also to the suggestion that reproductive failure and resource accumu-lation resulting from a climate-linked environmental veto,drives future reproductive synchronization in temperate tree species.展开更多
Ice core provides a valuable vertical timeline of past climates and anthropogenic activities.Environmental proxies have been widely used in these studies,but there are few biological indicators available.To address th...Ice core provides a valuable vertical timeline of past climates and anthropogenic activities.Environmental proxies have been widely used in these studies,but there are few biological indicators available.To address this gap,we investigated the bacterial community from a 74 m ice core of Muztag ata glacier on the Tibetan Plateau to link biological indicators with past climate and anthropogenic activities.By analyzing the portion of the ice core with environmental proxies available(corresponding to 1907 to 1991),we observed an increase in bacterial richness throughout the ice core,which was associated with higher NH_(4)^(+),an indicator of agricultural development.The bacterial community was jointly determined by human activity,natural input,and air temperature,with a strong human influence after the 1950s.Furthermore,the relative abundance of animal gut-associated bacteria,including Aerococcaceae,Nocardiaceae,Muribaculaceae,and Lachnospiraceae,was associated with livestock number changes in the Central Asian region.Together with other bacterial lineages,they jointly explained 59.8%of the livestock number changes.This study provides quantitative evidence of the associations between bacterial indicators and past climate and human activities,highlighting the potential of using bacterial proxies for ice core studies.展开更多
The future of the geosciences and geological research will involve complex scientific challenges,primarily concerning global and regional environmental issues,in the next 20-30 years.It is quite reasonable to suspect,...The future of the geosciences and geological research will involve complex scientific challenges,primarily concerning global and regional environmental issues,in the next 20-30 years.It is quite reasonable to suspect,based on current political and socioeconomic events,that young geoscientists will be faced with and involved in helping to resolve some well defined problems:water and energy security,the effects of anthropogenic climate change,coastal sea level rise and development,and the mitigation of geohazards.It is how we choose to approach these challenges that will define our future.Interdisciplinary applied research,improved modeling and prediction augmented with faster and more sophisticated computing,and a greater role in creating and guiding public policy,will help us achieve our goals of a cleaner and safer Earth environment in the next 30 years.In the far future,even grander possibilities for eliminating the risk of certain geohazards and finding sustainable solutions to our energy needs can be envisioned.Looking deeper into the future,the possibilities for geoscience research push the limits of the imagination.展开更多
基金supported by the National Natural Science Foundation(Nos.42275107,42121004,and 42375109)the National Key Research and Development Plan(No.2023YFC3706202)+1 种基金the Foundational and Applied Basic Research in Guangzhou in 2023(No.2023A04J0251)the Special Fund Project for Science and Technology Innovation Strategy of Guangdong Province(No.2019B121205004).
文摘The Pearl River Delta(PRD)region has been identified as a significant hotspot of wet ammonium deposition.However,the absence of long-term monitoring data in the area hinders the comprehension of the historical trends and changes in wet NH_(4)^(+)-N deposition in response to emissions,which interferes with the ability to make effective decisions.This study has analyzed the long-term trends of wet NH_(4)^(+)-N deposition flux and has quantified the effect of anthropogenic emissions and meteorological factors at a typical urban site and a typical forest site in the PRD region from 2009 to 2020.It revealed a significant decreasing trend in wet NH_(4)^(+)-N flux in both the typical urban and forest areas of the PRD region,at-6.2%/year(p<0.001)and-3.3%/year(p<0.001),respectively.Anthropogenic emissions are thought to have contributed 47%–57%of the wet NH_(4)^(+)-N deposition trend over the past 12 years compared to meteorological factors.Meteorological conditions dominated the interannual fluctuations in wet NH_(4)^(+)-N deposition with an absolute contribution of 46%–52%,while anthropogenic emissions change alone explained 10%–31%.NH_(3)emissions have the greatest impact on the urban area among anthropogenic emission factors,while SO_(2)emissions have the greatest impact on the forest area.Additionally,precipitation was identified as the primary meteorological driver for both sites.Our findings also imply that the benefits of NH_(3)emissions reductions might not immediately emerge due to interference from weather-related factors.
基金Under the auspices of Strategic and Special Frontier Project of Science and Technology of Chinese Academy of Sciences (No. XDA05080800)National Basic Research Program of China (No. 2010CB950102)National Natural Science Foundation of China (No. 40871007)
文摘Three global datasets, the History Database of the Global Environment （HYDE）, Kaplan and Krurnhardt （KK） and Pongratz of reconstructed anthropogenic land cover change （ALCC） were introduced and compared in this paper. The HYDE dataset was recon- structed by Goldewijk and his colleagues at the National institute of Public ttealth and the Environment in Netherland, covering the past 12 000 years. The KK dataset was reconstructed by Kaplan and his colleagues, the Soil-Vegetation-Atmosphere Research Group at the Institute of Environmental Engineering in Switzerland, covering the past 8000 years. The Pongratz dataset was reconstructed by Pon- gratz and her colleagues at the Max Planck Institute for Meteorology in Germany, coveting AD 800-1992. The results show that the reconstructed datasets are quite different from each other due to the different methods used. The three datasets all allocated the historical ALCC according to human population density. The main reason causing the differences among the three datasets lies on the different relationships between population density and land use used in each reconstructed dataset. The KK dataset is better than the other two datasets for two important reasons. First, it used the nonlinear relationship between population density and land use, while the other two used the linear relationship. Second, Kaplan and his colleagues adopted the technological development and intensification parameters and considered the wood harvesting and the long-term fallow area resulted from shifting cultivation, which were neglected in the recon- structions of the other two datasets. Therefore, the KK dataset is more suitable as one of the anthropogenic forcing fields for climate simulation over the past two millennia that is recently concerned by two projects, the National Basic Research Program and the Strategic and Special Frontier Project of Science and Technology of the Chinese Academy of Sciences.
文摘Today anthropogenic climate change is underway and predicted future global temperatures vary significantly. However, the drivers of current climate change and their links to Earth’s natural glacial cycle have yet to be fully resolved. Currently, many on a local level understand, and are exposed to, the heat energy generated by what’s referred to as the urban heat island effect (UHI), whereby natural flora with higher albedos </span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">is</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> replaced by manmade urban areas with lower albedos. This heat effect is not constrained to these regions and all anthropogenic surfaces with lower albedos need to be studied and quantified as the accumulated additional heat energy (infrared energy) is trapped within Earth’s atmosphere and could affect the Earth on a planetary level. Deployed satellites have detected critical changes to Earth’s albedo to lower levels, however the cause and impact of these changes have yet to be fully understood and incorporated into Global Circulation models (GCMs). Here it’s shown that industrialization of anthropogenic landscape practices of the past century has displaced millions of square kilometres of naturally high albedo grasslands with lower albedo agricultural landscapes. Utilising a fundamental Energy Balance Model, (EBM) it’s demonstrated these specific changes have generated vast amounts of additional heat energy which is trapped by the atmosphere, transferred and stored within the oceans of the Earth as shown in <b></span></span></span><a href="file:///E:/360data/%E9%87%8D%E8%A6%81%E6%95%B0%E6%8D%AE/%E6%A1%8C%E9%9D%A2/%E7%A9%BA%E7%99%BD%E9%A1%B5.docx#F1"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">Figure 1</span></b></span></span></a><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"></b></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">. The total additional heat energy accumulated over the preceding 110 years correlates to that required to warm the Earth to the levels seen to date, altering Earth’s overall energy budget. This energy will continue to accumulate and warm the Earth to a predicted 1.60 ± 0.20 Celsius by 2050 over 1910 levels. These findings are independent of anthropogenic Greenhouse Gas (GHG) additions and are further validated by predicting Earth’s temperature and albedo at the last glacial maxima, suggesting that an albedo cycle aligned to Gaia theory is the primary driver of Earth’s natural climate cycle.
文摘Efforts to restore urban rivers require an understanding of human-influenced changes in channel substrates. This study uses three naturally-occurring oxbows in a 3.5 km reach of Swan Creek, flowing through the City of Toledo, Ohio (USA) to reconstruct historical changes in channel substrate. Human impacts in the watershed were: 1) land clearance for agriculture (peaking in 1900-1920) and for suburban housing tracts (peaking in 1945-1970), followed by 2) the post-1940 creation of more efficient urban run-off systems from streets, parking lots, housing developments, and shopping centers. Historical aerial photographs and maps from 1935, 1940, 1950, 1963, 1974, and 1994 were georeferenced using ground control points, input to ArcGIS, and have root mean square error (RMSE) ranging from 0.19 - 0.77 m (average RMSE = 0.47 ± 0.20 m) when compared to the 2006 digital ortho quarter-quadrangle (DOQQ) image used as the basis for comparison. Results showed that channel sinuosity continually increased from 1.88 (1935) to 1.99 (2006). Two oxbows probably formed in 1913, and the third formed in 1940. Sediment cores and trenches were used to recognize historical channel substrates. Age control was provided by <sup>14</sup>C geochronology and labels on food packaging materials found in flood layers. Grain-size analysis of channel substrates shows a historical coarsening-upward trend: the largest clast size interval (f<sub>5</sub>) changes from +0.78f in pre-1935 channels, to -1.15f in pre-1940 channels, to -1.69f in the 2006 channel. These results indicate recent urban runoff created fluvial pavements and increasing channel mobility as the stream removes legacy sediment from intrabasinal sediment storage.
文摘Climate changes are one of the most significant aspects, which cause a threat to all human beings living on the planet Earth. Climate changes could happen due to both natural internal processes and external forcing, or due to persistent anthropogenic changes. The identified drastic temperature changes, increase in the emitted greenhouse gasses, and sea-level changes as witnessed from the acquired data;such as from ice cores, during the past centuries and even decades are all due to climate changes. Due to the increase in the emitted greenhouse gasses, major sectors in the Earth will be hit severely, such as agriculture and industry. Human welfare and health services will consequently suffer and development, in general, is going to be hampered. Large parts of the Earth will be unfavorable for living due to different reasons;such as inundation by seawater, decrease in temperature;however, some scientists believe that the increase in the percentages of the emitted greenhouse gasses has decreased or delayed the possibility of starting a new ice age. We have presented all possible scenarios, which may happen due to climate changes including temperature changes, emitted greenhouse gasses, sea level, and other harsh effects not only on human beings but all other living animal and plant species.
基金Acknowledgments This study was financially supported by the Shanghai Science and Technology Committee （10dz1210600）, the National Sea Welfare Project （201005019-09）, the Natural Science Foundation of China （41476075, 41340044）, and the China Geological Survey （12120115043101 ）.
文摘In recent years, intensifying waterlogging, salt water intrusion, wetland loss, and ecosystem degradation in Chinese delta cities and adjacent regions have generated the pressing need to create an urban form that is suited to both current and future climates incorporating sea level rise. However, adaptation planning uptake is slow. This is particularly unfortunate because patterns of urban form interact with mean sea level rise （MSLR） in ways that reduce or intensify its impact. There are currently two main barriers that are significant in arresting the implementation of adaptation planning with reference to the MSLR projections composed of geomorphologic MSLR projections and eustatic MSLR projections from global climate warming, and making a comprehensive risk assessment of MSLR projections. The present review shows recent progresses in mapping MSLR projections and their risk assessment approaches on Chinese delta cities, and then a perspective of adapting these cities to MSLR projections as following six aspects. 1） The geomorphologic MSLR projections are contributed by the natural tectonic subsidence projections and the MSLR projections by anthropogenic geomorphologic change. The former needs to be updated in a global framework. The latter is accumulated by land subsidence from underground water depletion, water level fall caused by the erosion of riverbeds from a sediment supply decline attributed to the construction of watershed dams, artificial sand excavation, water level raise by engineering projects including land reclamation, deep waterway regulation, and fresh water reservoirs. 2） Controlling MSLR projections by anthropogenic geomorphologic changes. 3） The IPCC AR5 RCPs MSLRs scenarios are expected to be projected to the local eustatic MSLR projections on the Chinese deltas. 4） The MSLR projections need to be matched to a local elevation datum. 5） Modeling approaches of regional river-sea numerical with semi- analytical hydrodynamics, estuarine channel network, system dynamics and adaptation points are perspective. 6） Adaptation planning to MSLR projections requires a comprehensive risk assessment of the risk of flood, fresh water supply shortage, coastal erosion, wetland loss, siltation of ports and waterway in Chinese delta cities and adjacent regions.
基金National Key Research and Development Program of China(No.2017YFE0100700)Natural Science Foundation of China(Nos.41801337,41976163)+4 种基金Research Grants of Science and Technology Commission of Shanghai Municipality(No.18ZR1410800)Fundamental Research Funds for the Central UniversitiesKey Laboratory of Land Subsidence Monitoring and Prevention,Ministry of Land and Resources(No.KLLSMP201503)Fund of the Director of the Key Laboratory of Geographic Information Science(Ministry of Education),East China Normal University(No.KLGIS2017C03)General Research Fund of Hong Kong Research Grants Council(RGC)(No.CUHK 14303818)。
文摘Coastal regions are becoming increasingly vulnerable to flooding because of accelerating sea-level-rise(SLR),local ground subsidence,and the changes in topography and morphology.Moreover,coastal areas are usually highly urbanized and increased human activities have an effect on the stability and preservation of the environment.For instance,the growing demand for new lands to accommodate the population and the industrial facilities in China has required the design and the deployment of land-reclamation projects from the ocean,with a marked impact on fragile coastal eco-systems.Specifically,the Yangtze River and Pearl River Estuary,two major estuaries of the world,have long been subject to intensive human activities over the past decades.Long-term ground subsidence evolution,topographic changes,and morphological variation of the coastal regions have drawn great attention.This paper provides an overview of well-established Earth Observation(EO)remote sensing(RS)technologies that are employed to continuously monitor the changes of urbanized regions.The combined use of EO-based DInSAR analyses along with the knowledge of the geomorphology of the coastal regions allows a more precise picture of the SLR risk in the investigated coastal regions.In this paper,we will concentrate on remote sensing technologies that allow the gathering of heterogeneous information,such as those based on the use of synthetic aperture radar(SAR),satellite altimeters and tide gauge data.We will underline how human activities trigger changes in the living environment of coastal zones and the associated risks for the population.Observed coastline changes,coastal regions terrain subsidence,and offshore bathymetry have a pronounced effect on the increasing risk of flooding.Accordingly,we also present insights into some inundation model projections employed for evaluating the potential flooding risk in coastal regions.
基金the German Research Association (DFG) (PR1175/1-1)
文摘In this paper the authors perform an extensive sensitivity analysis of the Indian summer monsoon rainfall to changes in parameters and boundary conditions which are influenced by human activities. For this study the authors use a box model of the Indian monsoon which reproduces key features of the observed monsoon dynamics such as the annual course of precipitation and the transitions between winter and summer regimes. Because of its transparency and computational efficiency, this model is highly suitable for exploring the effects of anthropogenic perturbations such as emissions of greenhouse gases and sulfur dioxide, and land cover changes, on the Indian monsoon. Results of a systematic sensitivity analysis indicate that changes in those parameters which are related to emissions of greenhouse gases lead to an increase in Indian summer rainfall. In contrast, all parameters related to higher atmospheric aerosol concentrations lead to a decrease in Indian rainfall. Similarly, changes in parameters which can be related to forest conversion or desertifieation, act to decrease the summer precipitation. The results indicate that the sign of precipitation changes over India will be dependent on the direction and relative magnitude of different human perturbations.
基金supported by the Met Office Hadley Centre Climate Programme funded by the Department for Business,Energy&Industrial Strategy(BEIS)the Department for Environment,Food&Rural Affairs(Defra)supported by the European Prototype demonstrator for the Harmonisation and Evaluation of Methodologies for attribution of extreme weather Events(EUPHEME)project,which is part of the European Research Area for Climate Services(ERA4CS),a European Research Area Network(ERA-NET)initiated by the Joint Programming Initiative‘‘Connecting Climate Knowledge for Europe”(JPI Climate)and co-funded by the European Union(690462)。
文摘Understanding the role of anthropogenic forcings in regional hydrological changes can help communities plan their adaptation in an informed manner.Here we apply attribution research methods to investigate the effect of human influence on historical trends in wet and dry summers and changes in the likelihood of extreme events in Europe.We employ an ensemble of new climate models and compare experiments with and without the effect of human influence to assess the anthropogenic contribution.Future changes are also analysed with projections to year 2100.We employ two drought indices defined relative to the pre-industrial climate:one driven by changes in rainfall only and one that also includes the effect of temperature via changes in potential evapotranspiration.Both indices suggest significant changes in European summers have already emerged above variability and are expected to intensify in the future,leading to widespread dryer conditions which are more extreme in the south.When only the effect of rainfall is considered,there is a distinct contrast between a shift towards wetter conditions in the north and dryer in the south of the continent,as well as an overall increase in variability.However,when the effect of warming is also included,it largely masks the wet trends in the north,resulting in increasingly drier summers across most of the continent.Historical index trends are already detected in the observations,while models suggest that what were extremely dry conditions in the pre-industrial climate will become normal in the south by the end of the century.
文摘Journal of Mountain Science(JMS)is a monthly peer-reviewed scientific journal covering research on natural and anthropogenic environmental changes and sustainable development in mountain areas.JMS is sponsored by Institute of Mountain Hazards and Environment,Chinese Academy of Sciences,supervised by Chinese Academy of Sciences,and published by Science Press and Springer Nature.JMS was launched in 2004 and indexed by SCI in 2007.JMS has a distinctly international character,with editorial board members and scientific editors from over 30 countries(regions)and international organizations,and authors and reviewers from more than 100 countries and regions.
基金Supported by the National Key Research and Development Program of China(2018YFC1507700)National Natural Science Foundation of China(42175175)Jiangsu Collaborative Innovation Center for Climate Change。
文摘There have been considerable high-impact extreme events occurring around the world in the context of climate change.Event attribution studies,which seek to quantitatively answer whether and to what extent anthropogenic climate change has altered the characteristics-predominantly the probability and magnitude-of particular events,have been gaining increasing interest within the research community.This paper reviews the latest approaches used in event attribution studies through a new classification into three major categories according to how the event attribution question is framed-namely,the risk-based approach,the storyline approach,and the combined approach.Four approaches in the risk-based framing category and three in the storyline framing category are also reviewed in detail.The advantages and disadvantages of each approach are discussed.Particular attention is paid to the ability,suitability,and applicability of these approaches in attributing extreme events in China,a typical monsoonal region where climate models may not perform well.Most of these approaches are applicable in China,and some are more suitable for analyzing temperature events.There is no right or wrong among these approaches,but different approaches have different framings.The uncertainties in attribution results come from several aspects,including different categories of framing,different conditions in climate model approaches,different models,different definitions of the event,and different observational data used.Clarification of these aspects can help to understand the differences in attribution results from different studies.
文摘Survival and successful reproduction require animals to make critical decisions amidst a naturally dynamic environmental and social background(i.e.“context”).However,human activities have pervasively,and rapidly,extended contextual variation into evolutionarily novel territory,potentially rendering evolved animal decision-making mechanisms and strategies maladaptive.We suggest that explicitly focusing on animal decision-making(ADM),by integrating and applying findings from studies of sensory ecology,cognitive psychology,behavioral economics and eco-evolutionary strategies,may enhance our understanding of,and our ability to predict how,human-driven changes in the environment and population demography will influence animal populations.Fundamentally,the decisions animals make involve evolved mechanisms,and behaviors emerge from the combined action of sensory integration,cognitive mechanisms and strategic rules of thumb,and any of these processes may have a disproportionate influence on behavior.Although there is extensive literature exploring ADM,it generally reflects a canalized,discipline-specific approach that lacks a unified conceptual framework.As a result,there has been limited application of ADM theory and research findings into predictive models that can enhance management outcomes,even though it is likely that the relative resilience of species to rapid environmental change is fundamentally a result of how ADM is linked to contextual variation.Here,we focus on how context influences ADM,and highlight ideas and results that may be most applicable to conservation biology.
文摘Aims Annually variable but synchronous production of large seed crops(‘masting’)is a widespread phenomenon in temperate trees.Mounting concerns about the impacts of anthropogenic climate change(ACC)on plant reproduction gives urgency to our need to understand better the role of climate on tree reproduction,and in particular,mast events.Unlike our understanding of reproductive phenology however,there is little consensus regarding how climate affects plant reproductive effort or indeed the actual environmental triggers that underpin masting behaviour.Methods We used a 27-year record of acorn yield from a population of 12 Quercus robur trees located in southern England to compare mast-ing frequency and post-dispersal acorn yield each year for each tree,with long-term weather data over the same period.We focussed on discrete or sequential climate cues(temperature,precipitation and frost days)as likely predictors of oak reproduction.Important Findings Annual post-dispersal acorn crop varied greatly;i.e.no acorns in 14 of the 27 years,but there was no sequential pattern of crop ver-sus non-crop years indicating that weather,rather than resource limitation alone,dictated the timing of reproduction.Crop years were instead most closely associated with relatively cool late sum-mer conditions in the preceding year,followed by anomalous sum-mer warmth within crop year.Acorn yield increased following dry April and above-average May and June temperatures within crop year.Although our results support a general association between warm late spring and summer conditions,and crop frequency and yield,respectively,the influence of cooler later summer conditions in the year prior to masting highlights how a combination of weather cues may dictate the occurrence of mast years.Consequently,our results corroborate not only the hypothesis that temperature differ-entials between consecutive years,not absolute temperatures,may be the better predictor of mast seeding events but lend support also to the suggestion that reproductive failure and resource accumu-lation resulting from a climate-linked environmental veto,drives future reproductive synchronization in temperate tree species.
基金supported by the National Key Research and Development Plans(Grant No.2021YFC2300904)the National Natural Science Foundation of China(Grant Nos.U21A20176 and 42330410)the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(Grant No.2019QZKK0503)。
文摘Ice core provides a valuable vertical timeline of past climates and anthropogenic activities.Environmental proxies have been widely used in these studies,but there are few biological indicators available.To address this gap,we investigated the bacterial community from a 74 m ice core of Muztag ata glacier on the Tibetan Plateau to link biological indicators with past climate and anthropogenic activities.By analyzing the portion of the ice core with environmental proxies available(corresponding to 1907 to 1991),we observed an increase in bacterial richness throughout the ice core,which was associated with higher NH_(4)^(+),an indicator of agricultural development.The bacterial community was jointly determined by human activity,natural input,and air temperature,with a strong human influence after the 1950s.Furthermore,the relative abundance of animal gut-associated bacteria,including Aerococcaceae,Nocardiaceae,Muribaculaceae,and Lachnospiraceae,was associated with livestock number changes in the Central Asian region.Together with other bacterial lineages,they jointly explained 59.8%of the livestock number changes.This study provides quantitative evidence of the associations between bacterial indicators and past climate and human activities,highlighting the potential of using bacterial proxies for ice core studies.
文摘The future of the geosciences and geological research will involve complex scientific challenges,primarily concerning global and regional environmental issues,in the next 20-30 years.It is quite reasonable to suspect,based on current political and socioeconomic events,that young geoscientists will be faced with and involved in helping to resolve some well defined problems:water and energy security,the effects of anthropogenic climate change,coastal sea level rise and development,and the mitigation of geohazards.It is how we choose to approach these challenges that will define our future.Interdisciplinary applied research,improved modeling and prediction augmented with faster and more sophisticated computing,and a greater role in creating and guiding public policy,will help us achieve our goals of a cleaner and safer Earth environment in the next 30 years.In the far future,even grander possibilities for eliminating the risk of certain geohazards and finding sustainable solutions to our energy needs can be envisioned.Looking deeper into the future,the possibilities for geoscience research push the limits of the imagination.
