The emissions of greenhouse gasses in Egypt are about 0.58% of the total emissions of the world in the year 2015, although Egypt is one of the countries most affected by the impacts of climate change. By assessment an...The emissions of greenhouse gasses in Egypt are about 0.58% of the total emissions of the world in the year 2015, although Egypt is one of the countries most affected by the impacts of climate change. By assessment and analysis of the expected economic impacts of climate change by the year 2030, the Egyptian cultivated area will be reduced to about 0.949 million acres, equal to about 8.22% of the Egyptian cultivated area compared with the case of no sinking part of the Delta land, thus reducing crop area in Egypt to about 1.406 million acres, approximately to about 6.25% of crop area compared with the case of no sinking part of the Delta land, in addition to surplus in the Egyptian balance water to about 2.48 billion m3. In this case value of the Egyptian agriculture production will decrease by about 6.19 billion dollars, equal to about 6.19% compared with presumably no sinking of the Delta land. In the case of sinking 15% of Delta lands, with the change of the productivity and water consumption of most crops, the result will be a reduction in the cultivated area to about 0.94 million acres. In addition to decreasing the Egyptian crop area to about 1.39 million acres, with a deficit in the Egyptian balance water to about 4.74 billion m3 compared to the case of no sinking part of the Delta land, the cultivated area will decrease to about 8.17%, and the crop area will decrease 6.18%. Also, the value of the Egyptian agriculture production will decrease by about 12.51%. While compared to sinking part of the Delta land to about 15% of the total Delta area without the other impacts of climate change, the cultivated area will increase by about 0.06%;the crop area will increase by about 0.08%;also, the value of the Egyptian agriculture production will decrease by about 5.57%.展开更多
Global climate change is real and already taking place. The most recent Fifth Assessment Report of the Intergov- ernmental Panel on Climate Change (IPCC AR5) stated that global land and ocean surface temperature inc...Global climate change is real and already taking place. The most recent Fifth Assessment Report of the Intergov- ernmental Panel on Climate Change (IPCC AR5) stated that global land and ocean surface temperature increased by 0.85℃ over the period of 1880 to 2012 (IPCC Climate Change 2013). China is among the most affected countries by global climate change.展开更多
Ecosystem of eastern Eurasian steppe is facing more and more challenges of global issues such as climate change, food and ecological security and human excessive utilization since the 21st century. Facing on the incre...Ecosystem of eastern Eurasian steppe is facing more and more challenges of global issues such as climate change, food and ecological security and human excessive utilization since the 21st century. Facing on the increasingly prominent international issues, it is very essential for relevant countries, international organizations and domestic counterparts to enhance systematic and mutual cooperation and exchanges to carry out scientific research and develop protection practice on the Eurasian steppe.展开更多
Background: Measurements of tree heights and diameters are essential in forest assessment and modelling. Tree heights are used for estimating timber volume, site index and other important variables related to forest ...Background: Measurements of tree heights and diameters are essential in forest assessment and modelling. Tree heights are used for estimating timber volume, site index and other important variables related to forest growth and yield, succession and carbon budget models. However, the diameter at breast height (dbh) can be more accurately obtained and at lower cost, than total tree height. Hence, generalized height-diameter (h-d) models that predict tree height from dbh, age and other covariates are needed. For a more flexible but biologically plausible estimation of covariate effects we use shape constrained generalized additive models as an extension of existing h-d model approaches. We use causal site parameters such as index of aridity to enhance the generality and causality of the models and to enable predictions under projected changeable climatic conditions. Methods: We develop unconstrained generalized additive models (GAM) and shape constrained generalized additive models (SCAM) for investigating the possible effects of tree-specific parameters such as tree age, relative diameter at breast height, and site-specific parameters such as index of aridity and sum of daily mean temperature during vegetation period, on the h-d relationship of forests in Lower Saxony, Germany. Results: Some of the derived effects, e.g. effects of age, index of aridity and sum of daily mean temperature have significantly non-linear pattern. The need for using SCAM results from the fact that some of the model effects show partially implausible patterns especially at the boundaries of data ranges. The derived model predicts monotonically increasing levels of tree height with increasing age and temperature sum and decreasing aridity and social rank of a tree within a stand, The definition of constraints leads only to marginal or minor decline in the model statistics like AIC An observed structured spatial trend in tree height is modelled via 2-dimensional surface fitting. Conclusions: We demonstrate that the SCAM approach allows optimal regression modelling flexibility similar to the standard GAM but with the additional possibility of defining specific constraints for the model effects. The longitudinal character of the model allows for tree height imputation for the current status of forests but also for future tree height prediction.展开更多
It is becoming clear that Climate Change is getting severe. It was reported that the improved ocean heat measurements have a rate of warming upwards from 4 to 5 Hiroshima bombs liberated heat per second or 388,800 per...It is becoming clear that Climate Change is getting severe. It was reported that the improved ocean heat measurements have a rate of warming upwards from 4 to 5 Hiroshima bombs liberated heat per second or 388,800 per day. It was reported also that our climate has accumulated the equivalent of a total of more than 2.8 billion Hiroshima bombs’ worth of heat since 1998. Despite this global concern about the effect of global change on environment, it is believed that the problem is much more severe and with greater impact on all facets of life. The effect of Climate Change, especially with a 1℃increase in global temperature (from 14℃to 15℃) is equivalent to the heat liberated from explosion of about 300 million Hiroshima of atomic bomb. This is why this CoP 26 becomes more serious and had targeted year 2060 as a year of zero CO<sub>2</sub> emission. This paper discusses the impact of climate change on ten sectors;water, water desalination, energy, renewable energy supply, health, society, agriculture, economy, industry, and built environment.展开更多
Because of the complexity of social responses to climate change,as well as limitations of proxy data concerning interactions between climate change and human responses,the social impacts of past climate change and ass...Because of the complexity of social responses to climate change,as well as limitations of proxy data concerning interactions between climate change and human responses,the social impacts of past climate change and associated response mechanisms,thus,require further investigation.To shed light on the transmission of climate change impacts within historical Chinese society,we selected 30-year resolution sequences of temperature anomalies in eastern China and 10-year resolution sequences of grain harvest grades,famine indices,and frequencies of peasant uprisings in China over the past 2000 years.Using a food security perspective,we analyzed the impacts of temperature changes historically transmitted through Chinese production,population,and social subsystems,and differences in transmission characteristics between cold and warm units.Our results were as follows.(1)From 210 BC to 1910 AD,temperature changes in China were significantly positively correlated with grain harvest grades(correlation coefficient,0.338),and significantly negatively correlated with famine indices,and frequencies of peasant uprisings(correlation coefficients,-0.301 and-0.277,respectively).The correlation coefficients between famine indices and grain harvest grades or frequencies of peasant uprisings were very low.(2)There was a higher proportion of bumper or normal harvests(86.5%of the total decades),more moderate and mild famines(76%),and a lower proportion of peasant uprisings(33.3%)in the 30-year warm units.Conversely,there was a higher proportion of poor or normal harvests(70.7%),a greater proportion of moderate and severe famines(77.6%),and more peasant uprisings(51.7%)in the 30-year cold units.(3)Of the 23 main transmission pathways extending from temperature change to the social subsystem,13 occurred in cold units,of which 7 had an endpoint of peasant uprisings,and 10 occurred in warm units of which 3 had an endpoint of peasant uprisings.The main transmission pathways that were more likely to be associated with the impacts of temperature change were:Cold→poor harvests→severe famines→more uprisings;cold→poor harvests→moderate famines→more uprisings;warm→bumper harvests→mild famines→no uprisings;warm→bumper harvests→moderate harvests→no uprisings;warm→normal harvests→mild famines→no uprisings;and warm→normal harvests→moderate famines→no uprisings.(4)The transmission of the impacts of temperature change was a complex process.Within this process,famine was most prone to being modulated by human society.In the transmission pathways from the production to the social subsystem,there was a stepwise decrease in the occurrence rate of decades that were probably affected by climate change.In all cold units,10.4%of decades ending in more uprisings were most likely to be associated with the impacts of temperature change.In all warm units,47.9%of decades ending in no uprisings were most likely to be associated with the impacts of temperature change.This research can contribute a better understanding on the past interaction mechanisms and processes within the human-climate-ecosystem complex,as well as a better response to the impacts of the ongoing climate change.展开更多
Historical case studies of climate change impacts and the resulting social responses can provide analogies for better under- standing the impacts of current and future climate changes. Around the turn of the 19th cent...Historical case studies of climate change impacts and the resulting social responses can provide analogies for better under- standing the impacts of current and future climate changes. Around the turn of the 19th century, the climate of the North China Plain experienced a shift from a relatively warm stage in the 18th century to a colder stage in the 19th century, which was characterised by a much colder climate and more frequent and severe floods and droughts. Historical information about refu- gees, social disorder, grain transportation, and disaster relief on the North China Plain in 1780-1819 is collected from the Ver- itable Records of the Qing Dynasty (a collection of official records). The mechanism of climate change affecting the food se- curity of the society, as indicated by the development of a refugee problem around the turn of the 19th century, is analyzed by examining the social vulnerability. There are four basic findings: (1) In the 40 years from 1780-1819, the society on the North China Plain was unstable and characterised by a significant deterioration of the refugee situation. The number of refugees in- creased markedly, and their behaviour became increasingly violent. In the 1780s, most of the disaster victims chose to stay at their residences waiting for relief. From 1790 to 1800, hundreds of thousands of refugees migrated to northeast China. In the 1810s, the frequency of farmer rebellions increased sharply. (2) The increase in instability corresponded to the climatic cooling over the same time period. The increased instability was a result of the negative impacts of climate change accumulating and transmitting to the social level. (3) For food security, a precondition for the negative impacts of climate change on human soci- ety was the vulnerability of the regional socioeconomic system, which had a high sensitivity and low capacity to respond. This vulnerability could be described by the following three observations: O The regional balance of supply and demand for food was in a critical state, which led to a high sensitivity and dramatic reduction in yield that was caused by climate change; (~ the capacity for disaster relief efforts by the government was too low to meet the needs of crisis management; (~ the capacity for refugees' resettlement in eastern Inner Mongolia and northeast China, which both border the North China Plain, was se- verely restricted by climatic conditions or the quarantine policy. (4) It is estimated that climate change caused the social vul- nerability to reach a critical level approximately 20 years earlier on the North China Plain.展开更多
文摘The emissions of greenhouse gasses in Egypt are about 0.58% of the total emissions of the world in the year 2015, although Egypt is one of the countries most affected by the impacts of climate change. By assessment and analysis of the expected economic impacts of climate change by the year 2030, the Egyptian cultivated area will be reduced to about 0.949 million acres, equal to about 8.22% of the Egyptian cultivated area compared with the case of no sinking part of the Delta land, thus reducing crop area in Egypt to about 1.406 million acres, approximately to about 6.25% of crop area compared with the case of no sinking part of the Delta land, in addition to surplus in the Egyptian balance water to about 2.48 billion m3. In this case value of the Egyptian agriculture production will decrease by about 6.19 billion dollars, equal to about 6.19% compared with presumably no sinking of the Delta land. In the case of sinking 15% of Delta lands, with the change of the productivity and water consumption of most crops, the result will be a reduction in the cultivated area to about 0.94 million acres. In addition to decreasing the Egyptian crop area to about 1.39 million acres, with a deficit in the Egyptian balance water to about 4.74 billion m3 compared to the case of no sinking part of the Delta land, the cultivated area will decrease to about 8.17%, and the crop area will decrease 6.18%. Also, the value of the Egyptian agriculture production will decrease by about 12.51%. While compared to sinking part of the Delta land to about 15% of the total Delta area without the other impacts of climate change, the cultivated area will increase by about 0.06%;the crop area will increase by about 0.08%;also, the value of the Egyptian agriculture production will decrease by about 5.57%.
文摘Global climate change is real and already taking place. The most recent Fifth Assessment Report of the Intergov- ernmental Panel on Climate Change (IPCC AR5) stated that global land and ocean surface temperature increased by 0.85℃ over the period of 1880 to 2012 (IPCC Climate Change 2013). China is among the most affected countries by global climate change.
文摘Ecosystem of eastern Eurasian steppe is facing more and more challenges of global issues such as climate change, food and ecological security and human excessive utilization since the 21st century. Facing on the increasingly prominent international issues, it is very essential for relevant countries, international organizations and domestic counterparts to enhance systematic and mutual cooperation and exchanges to carry out scientific research and develop protection practice on the Eurasian steppe.
文摘Background: Measurements of tree heights and diameters are essential in forest assessment and modelling. Tree heights are used for estimating timber volume, site index and other important variables related to forest growth and yield, succession and carbon budget models. However, the diameter at breast height (dbh) can be more accurately obtained and at lower cost, than total tree height. Hence, generalized height-diameter (h-d) models that predict tree height from dbh, age and other covariates are needed. For a more flexible but biologically plausible estimation of covariate effects we use shape constrained generalized additive models as an extension of existing h-d model approaches. We use causal site parameters such as index of aridity to enhance the generality and causality of the models and to enable predictions under projected changeable climatic conditions. Methods: We develop unconstrained generalized additive models (GAM) and shape constrained generalized additive models (SCAM) for investigating the possible effects of tree-specific parameters such as tree age, relative diameter at breast height, and site-specific parameters such as index of aridity and sum of daily mean temperature during vegetation period, on the h-d relationship of forests in Lower Saxony, Germany. Results: Some of the derived effects, e.g. effects of age, index of aridity and sum of daily mean temperature have significantly non-linear pattern. The need for using SCAM results from the fact that some of the model effects show partially implausible patterns especially at the boundaries of data ranges. The derived model predicts monotonically increasing levels of tree height with increasing age and temperature sum and decreasing aridity and social rank of a tree within a stand, The definition of constraints leads only to marginal or minor decline in the model statistics like AIC An observed structured spatial trend in tree height is modelled via 2-dimensional surface fitting. Conclusions: We demonstrate that the SCAM approach allows optimal regression modelling flexibility similar to the standard GAM but with the additional possibility of defining specific constraints for the model effects. The longitudinal character of the model allows for tree height imputation for the current status of forests but also for future tree height prediction.
文摘It is becoming clear that Climate Change is getting severe. It was reported that the improved ocean heat measurements have a rate of warming upwards from 4 to 5 Hiroshima bombs liberated heat per second or 388,800 per day. It was reported also that our climate has accumulated the equivalent of a total of more than 2.8 billion Hiroshima bombs’ worth of heat since 1998. Despite this global concern about the effect of global change on environment, it is believed that the problem is much more severe and with greater impact on all facets of life. The effect of Climate Change, especially with a 1℃increase in global temperature (from 14℃to 15℃) is equivalent to the heat liberated from explosion of about 300 million Hiroshima of atomic bomb. This is why this CoP 26 becomes more serious and had targeted year 2060 as a year of zero CO<sub>2</sub> emission. This paper discusses the impact of climate change on ten sectors;water, water desalination, energy, renewable energy supply, health, society, agriculture, economy, industry, and built environment.
基金supported by the Major State Basic Research Development Program of China (Grant No. 2010CB950103)the National Natural Science Foundation of China (Grant No. 41371201)the Strategic Project of Science and Technology of the Chinese Academy of Sciences (Grant No. XDA05080102)
文摘Because of the complexity of social responses to climate change,as well as limitations of proxy data concerning interactions between climate change and human responses,the social impacts of past climate change and associated response mechanisms,thus,require further investigation.To shed light on the transmission of climate change impacts within historical Chinese society,we selected 30-year resolution sequences of temperature anomalies in eastern China and 10-year resolution sequences of grain harvest grades,famine indices,and frequencies of peasant uprisings in China over the past 2000 years.Using a food security perspective,we analyzed the impacts of temperature changes historically transmitted through Chinese production,population,and social subsystems,and differences in transmission characteristics between cold and warm units.Our results were as follows.(1)From 210 BC to 1910 AD,temperature changes in China were significantly positively correlated with grain harvest grades(correlation coefficient,0.338),and significantly negatively correlated with famine indices,and frequencies of peasant uprisings(correlation coefficients,-0.301 and-0.277,respectively).The correlation coefficients between famine indices and grain harvest grades or frequencies of peasant uprisings were very low.(2)There was a higher proportion of bumper or normal harvests(86.5%of the total decades),more moderate and mild famines(76%),and a lower proportion of peasant uprisings(33.3%)in the 30-year warm units.Conversely,there was a higher proportion of poor or normal harvests(70.7%),a greater proportion of moderate and severe famines(77.6%),and more peasant uprisings(51.7%)in the 30-year cold units.(3)Of the 23 main transmission pathways extending from temperature change to the social subsystem,13 occurred in cold units,of which 7 had an endpoint of peasant uprisings,and 10 occurred in warm units of which 3 had an endpoint of peasant uprisings.The main transmission pathways that were more likely to be associated with the impacts of temperature change were:Cold→poor harvests→severe famines→more uprisings;cold→poor harvests→moderate famines→more uprisings;warm→bumper harvests→mild famines→no uprisings;warm→bumper harvests→moderate harvests→no uprisings;warm→normal harvests→mild famines→no uprisings;and warm→normal harvests→moderate famines→no uprisings.(4)The transmission of the impacts of temperature change was a complex process.Within this process,famine was most prone to being modulated by human society.In the transmission pathways from the production to the social subsystem,there was a stepwise decrease in the occurrence rate of decades that were probably affected by climate change.In all cold units,10.4%of decades ending in more uprisings were most likely to be associated with the impacts of temperature change.In all warm units,47.9%of decades ending in no uprisings were most likely to be associated with the impacts of temperature change.This research can contribute a better understanding on the past interaction mechanisms and processes within the human-climate-ecosystem complex,as well as a better response to the impacts of the ongoing climate change.
基金supported by National Basic Researh Program of China(Grant No. 2010CB950103)National Natural Science Foundation of China (Grant No. 41071127)
文摘Historical case studies of climate change impacts and the resulting social responses can provide analogies for better under- standing the impacts of current and future climate changes. Around the turn of the 19th century, the climate of the North China Plain experienced a shift from a relatively warm stage in the 18th century to a colder stage in the 19th century, which was characterised by a much colder climate and more frequent and severe floods and droughts. Historical information about refu- gees, social disorder, grain transportation, and disaster relief on the North China Plain in 1780-1819 is collected from the Ver- itable Records of the Qing Dynasty (a collection of official records). The mechanism of climate change affecting the food se- curity of the society, as indicated by the development of a refugee problem around the turn of the 19th century, is analyzed by examining the social vulnerability. There are four basic findings: (1) In the 40 years from 1780-1819, the society on the North China Plain was unstable and characterised by a significant deterioration of the refugee situation. The number of refugees in- creased markedly, and their behaviour became increasingly violent. In the 1780s, most of the disaster victims chose to stay at their residences waiting for relief. From 1790 to 1800, hundreds of thousands of refugees migrated to northeast China. In the 1810s, the frequency of farmer rebellions increased sharply. (2) The increase in instability corresponded to the climatic cooling over the same time period. The increased instability was a result of the negative impacts of climate change accumulating and transmitting to the social level. (3) For food security, a precondition for the negative impacts of climate change on human soci- ety was the vulnerability of the regional socioeconomic system, which had a high sensitivity and low capacity to respond. This vulnerability could be described by the following three observations: O The regional balance of supply and demand for food was in a critical state, which led to a high sensitivity and dramatic reduction in yield that was caused by climate change; (~ the capacity for disaster relief efforts by the government was too low to meet the needs of crisis management; (~ the capacity for refugees' resettlement in eastern Inner Mongolia and northeast China, which both border the North China Plain, was se- verely restricted by climatic conditions or the quarantine policy. (4) It is estimated that climate change caused the social vul- nerability to reach a critical level approximately 20 years earlier on the North China Plain.