The analysis of Greenhouse Effect experiments in the public domain indicated that the lab tests were primarily centered around illustrating the mechanics of conventional greenhouses. They used high-energy visible ligh...The analysis of Greenhouse Effect experiments in the public domain indicated that the lab tests were primarily centered around illustrating the mechanics of conventional greenhouses. They used high-energy visible light (such as sunlight), rather than addressing the Greenhouse Effect, which involves low-energy infrared radiation emitted by the Earth’s surface. Studies with argon, a non-greenhouse gas with similar density to CO2, showed thermal heat transfer as the dominant factor in the temperature profiles, with radiation absorption being undetected. The same conclusion was drawn by another study, which measured infrared back radiation. Experiments using exaggerated CO2 concentrations inadvertently illustrated the principle of the Popper Falsification Test by disproving the Greenhouse Effect applicable to CO2 within the troposphere. A straightforward kitchen test showed that a microwave oven cannot be used as a model for the Greenhouse Effect.展开更多
Before there were humans, the world changed only slowly. The climate warmed and cooled, new plants and animals developed and became extinct (绝灭的) in their turn, and sea level rose and fell over periods of thousands...Before there were humans, the world changed only slowly. The climate warmed and cooled, new plants and animals developed and became extinct (绝灭的) in their turn, and sea level rose and fell over periods of thousands, if not millions of years. But during the last two thousand years great changes have taken place. Forests have disap-展开更多
Impacts of greenhouse effects (2 × CO2) upon climate change over China as simulated by a regional climate model over China (RegCM / China) have been investigated. The model was based on RegCM2 and was nested to a...Impacts of greenhouse effects (2 × CO2) upon climate change over China as simulated by a regional climate model over China (RegCM / China) have been investigated. The model was based on RegCM2 and was nested to a global coupled ocean-atmosphere model (CSIRO R21L9 AOGCM model). Results of the control run (1 × CO2) indicated that simulations of surface air temperature and precipitation in China by RegCM are much better than that by the global coupled model because of a higher resolution. Results of sensitive experiment by RegCM with 2 × CO2 showed that the surface air temperature over China might increase remarkably due to greenhouse effect, especially in winter season and in North China. Precipitation might also increase in most parts of China due to the CO2 doubling. Key words Regional climate model - Greenhouse effect This research was supported by National Key Programme for Developing Basic Sciences (G1998040900 — Part I), Chinese Academy of Sciences Key Program KZCX2-203 and KZ981-B1-108.展开更多
We mainly discuss changes of precipitation in China due to growinggreenhouse gases using GCM1 model assuming the IPCC 'Business-as-Usual'Scenario. An increasing greenhouse effect will lead to precipitatio...We mainly discuss changes of precipitation in China due to growinggreenhouse gases using GCM1 model assuming the IPCC 'Business-as-Usual'Scenario. An increasing greenhouse effect will lead to precipitation increasesmostly in north of 30°N for winter, and strongly increases alap a slant belt fromNortheast China to Bay of Bangal for summer in China. The mp of increasingprecipitation are about 7.9, -0.7 and 13.6 percent for winter, and 6.4, 12.9 and 8.4percent for summer m China, Changjinang and Huanghe river valleys, respectively.The model results are also shown to imply that an increasing greenhouse effectenhances chanas of intense storms and shown for winter and summer in China.展开更多
An obvious warming in China induced by doubled carbon, dioxide as simulated by the climatic models have been found. It is also noticed that there might be drying or wetting in some parts of China induced by doubled CO...An obvious warming in China induced by doubled carbon, dioxide as simulated by the climatic models have been found. It is also noticed that there might be drying or wetting in some parts of China induced by doubled CO2 as simulated by the general circulation models(GCMs). Agricultural productivity mainly depends on the temperature, rainfall and soil moisture in China. The changes of agricultural productivity in the different parts of China induced by doubled CO2 have been estimated in this paper. It is shown that the greenhouse effect might cause increasing production in some parts of China and decreasing production in other parts of China.展开更多
The physical processes associated with the clear-sky greenhouse effect in the presence of water vapor are examined by including surface emissivity in the greenhouse effect formulation, and by introducing a new way to ...The physical processes associated with the clear-sky greenhouse effect in the presence of water vapor are examined by including surface emissivity in the greenhouse effect formulation, and by introducing a new way to partition physical processes of the greenhouse effect. In this new framework, it is found that the clear-sky greenhouse effect is governed by three physical processes associated with (1) the temperature contrast between the surface and the atmosphere, (2) the interaction between the surface emissivity and the temperature contrast, and (3) the surface emissivity. The importance of the three physical processes is assessed by computing their vertical and spectral variations far the subarctic winter and summer standard atmosphere using the radiation model MODTRAN3 (Moderate Resolution Transmittance code Version 3). The results show that the process associated with the temperature contrast between the surface and the atmosphere dominates over the other two processes in magnitude. The magnitude of this process has substantial variations in the spectral region of 1250 to 1880 cm-1 and in the far infrared region. Due to the low-level temperature inversion over the subarctic winter, there exists a negative contribution to the greenhouse trapping. The seasonal variations are, however, dominated by the processes associated with the interaction between the surface emissivity and the temperature contrast as well as the surface emissivity itself. The magnitudes of these two physical processes contributing to the greenhouse trapping over the subarctic winter are about 7 to 10 times of those over the subarctic summer, whereas the magnitude of the processes associated with the temperature contrast in the subarctic summer is only about 2 times of that in the subarctic winter.展开更多
Climatic changes can be separated into two parts: natural changes -and human activity influenced on climatic changes. The observed data could not only show the effects caused by human activity. Several simulated resul...Climatic changes can be separated into two parts: natural changes -and human activity influenced on climatic changes. The observed data could not only show the effects caused by human activity. Several simulated results as simulated by the GCMs induced by the greenhouse effects in China .have been analysed. It is shown that an obvious warming of about 3-6℃ in winter and 2-5℃ in summer in China as simulated by the GCMs induced by doubling CO2 have been found. There are getting drier or wetter regions in China due to doubled CO2 as simulated by most of models. Comparing the simulated results with the observed data in China, some simulated results are able to be believed. The GCMs should be improved, especially in the regional areas.展开更多
In carbon global cycle, the relationship between the terrestrial ecosystem and the atmosphere where there are, among others, gases that contribute to the greenhouse effect, has become object of relevant scientific int...In carbon global cycle, the relationship between the terrestrial ecosystem and the atmosphere where there are, among others, gases that contribute to the greenhouse effect, has become object of relevant scientific interest. The content of organic matter in soil, expressed by its supplies as well as the organic matter degree of stability, are factors that can prevent the soil from acting as a drain and at the same time contribute for it to become a source of those gases. The variations in the way land is used in Brazil are factors responsible for the increase in emission of greenhouse effect gases. Based on these facts, this study was aimed to evaluate the CO2 and CH4 efflux using a gas retention chamber, and to associate these emissions to the organic carbon content in the soil. Two different areas were selected for the study, one in Tijuca Forest National Park, in a forest area, and the other at the Rio de Janeiro Federal Rural University campus. In the latter, the area was stratified in three sub areas according to the vegetation, use and water saturation degree. Samplings were performed during 8 months between 2013 and 2014.展开更多
Over the past two years, the food culture of the small town of Agarfa in south Ethiopia has seen some tasty changes. Tomatoes, previously unaffordable to all but the very wealthy, have become a common sight on the pla...Over the past two years, the food culture of the small town of Agarfa in south Ethiopia has seen some tasty changes. Tomatoes, previously unaffordable to all but the very wealthy, have become a common sight on the plates of local people. The secret lies in the introduction of greenhouse tomato growing technology.展开更多
Impacts of greenhouse effects (2×CO_2) on climate change over China as simulated by a regional climate model have been investigated.The model was based on RegCM2 and is nested in one-way mode within a global coup...Impacts of greenhouse effects (2×CO_2) on climate change over China as simulated by a regional climate model have been investigated.The model was based on RegCM2 and is nested in one-way mode within a global coupled atmosphere-ocean model (CSIRO R21L9 AOGCM).Two multi-year simulations,the control run with normal CO_2 concentration and sensitivity run with doubled CO_2 concentration are conducted. As Part II of the publications,with a brief analysis of the 2×CO_2 experiment by CSIRO R21Lg,results of the 2×CO_2 simulation by RegCM2 are analyzed in detail. Results of the RegCM show a remarkably warming over China with an increment ranging from 2.2℃ in southern China to 2.8℃ in northern due to greenhouse effect.The regional averaged annual temperature increase is 2.5℃.The warming is greater in winter and spring.Daily maximum and minimum temperatures increase also over China which lead to much more hot spell days in summer and less cold spell days in winter. Precipitation increases in all seasons of the year,with the greatest found in summer.Annual mean precipitation increases significantly in western China,parts of the area in south of the Yangtze River and northern part of the Northeast.while a decrease in the area from southern part of the Northeast to North China is simulated.The regional averaged annual increase of precipitation is 12%.More heavy rain events are found noticeably in southern China.The simulated tropical storms affecting and landing over China tend to increase.Analysis on the simulation of circulation pattern showed that the 500 hPa height in East Asia might rise significantly.展开更多
Accurate measurements of the three-dimensional structure characteristics of urban buildings and their greenhouse effect are important for evaluating the impact of urbanization on the radiation energy budget and resear...Accurate measurements of the three-dimensional structure characteristics of urban buildings and their greenhouse effect are important for evaluating the impact of urbanization on the radiation energy budget and research on the urban heat island(UHI)effect.The decrease in evapotranspiration or the increase in sensible heat caused by urbanization is considered to be the main cause of the UHI effect,but little is known about the influence of the main factor“net radiant flux”of the urban surface heat balance.In this study,experimental observation and quantitative model simulation were used to find that with the increase of building surface area after urbanization,the direct solar radiation flux and net radiation flux on building surface areas changed significantly.In order to accurately quantify the relationship between the positive and negative effects,this study puts forward the equivalent calculation principle of“aggregation element”,which is composed of a building’s sunny face and its shadow face,and the algorithm of the contribution of the area to thermal effect.This research clarifies the greenhouse effect of a building with walls of glass windows.Research shows that when the difference between absorption rates of a concrete wall and grass is−0.21,the cooling effect is shown.In the case of concrete walls with glass windows,the difference between absorption rates of a building wall and grass is−0.11,which is also a cooling effect.The greenhouse effect value of a building with glass windows reduces the cooling effect value to 56%of the effect of a building with concrete walls.The simulation of changes in net radiant flux and flux density shows that the greenhouse effect of a 5-story building with windows yields 15.5%less cooling effect than one with concrete walls,and a 30-story building with windows reduces the cooling effect by 23.0%.The simulation results confirmed that the difference in the equivalent absorption rate of the aggregation element is the“director”of cooling and heating effects,and the area of the aggregation element is the“amplifier”of cooling and heating effects.At the same time,the simulation results prove the greenhouse effect of glass windows,which significantly reduces the cold effect of concrete wall buildings.The model reveals the real contribution of optimized urban design to mitigating UHI and building a comfortable environment where there is no atmospheric circulation.展开更多
This paper describes a diagnostic study of the feedback mechanism in greenhouse effects of increased CO_2 and oth- er trace gases(CH_4,N_2O and CFCs),simulated by general circulation model.The study is based on two se...This paper describes a diagnostic study of the feedback mechanism in greenhouse effects of increased CO_2 and oth- er trace gases(CH_4,N_2O and CFCs),simulated by general circulation model.The study is based on two sensitivity exper- iments for doubled CO_2 and the inclusion of other trace gases,respectively,using version one of the community climate model(CCM1)developed at the National Centre for Atmospheric Research.A one-dimensional(1-D)and a two-dimensional(2-D)radiative-convective models are used to diagnose the feedback effect.It shows that the feedback factors in global and annual mean conditions are in the sequence of surface albedo,water vapor amount,water vapor distribution,cloud height,critical lapse rate and cloud cover,while in zonal and annual mean conditions in the tropical region the above sequence does not change except the two water vapor terms being the largest feedback compo- nents.Among the feedback components,the total water vapor feedback is the largest(about 50%).The diagnosis also gives a very small feedback of either the cloud cover or the lapse rate,which is substantially different from the 1-D feedback analysis by Hansen et al.(1984).The small lapse rate feedback is considered to be partly caused by the convective adjustment scheme adopted by CCM1 model. The feedback effect for doubled CO_2 is very different from that of the addition of other trace gases because of their different vertical distributions of radiative forcing although the non-feedback responses of surface air temperature for both cases are almost the same.For instance,the larger forcing at surface by the addition of other trace gases can cause stronger surface albedo feedback than by doubled CO_2.Besides,because of the negative forcing of doubled CO_2 in the stratosphere,cloud height feedback is more intense.The larger surface forcing in the case of other trace gases can also in- fluence atmospheric water vapor amount as well as the water vapor distribution,which will in turn have stronger feedback effects.All these indicate that it is incorrect to use“effective CO_2”to replace other trace gases in the general circulation model.展开更多
Two one-dimensional radiative-convective models with the same scheme and the different ranges that one is from surface to stratopause and the other is from surface to tropopause,have been developed to study the role p...Two one-dimensional radiative-convective models with the same scheme and the different ranges that one is from surface to stratopause and the other is from surface to tropopause,have been developed to study the role played by the stratosphere in greenhouse effect.It is shown that the addition of stratospheric response may lead to an increase of 7—50 percent in radiative forcing at the tropopause,and an increase of 20—60 percent in surface temperature when the con- centration of the same gas in the two models increases at the same time;and when the same change in radiative forcing at the tropopause due to the same agent in the two models occurs,the addition of stratospheric response may lead to an in- crease of 5—20 percent in surface temperature;and allowing for the stratospheric adjustment means that the tempera- ture responses to the same flux change due to different causes are in far disagreement.展开更多
The global mean temperatures of the atmosphere and the surface of various planets of the solar system are deter- mined by taking the system as in radiative equilibrium,with the atmosphere taken as transparent to solar...The global mean temperatures of the atmosphere and the surface of various planets of the solar system are deter- mined by taking the system as in radiative equilibrium,with the atmosphere taken as transparent to solar radiation but with an albedo α,and composed of N layers each of which absorbs all infrared radiation that falls on it,and a top layer of partial absorptivity a,while the surface is taken as black.It is found that,for the earth's atmosphere with α=0.33, N=0,a=0.83,it gives the current observed mean surface temperature T_s=15℃ and the effective mean radiative temper- ature of the atmosphere T_a=242.6K.On the other hand;the atmosphere of Venus is characterized by α=0.70 and N=70,which yields a surface temperature of about 700K. It is also found that surface evaporation and absorption of solar radiation by the atmosphere tend to lower the sur- face temperature.展开更多
In this study,we put forward a radiative-convective-transportive energy balance model of a gray atmosphere to examine individual roles of the greenhouse effect of water vapor,vertical convection,and atmospheric polewa...In this study,we put forward a radiative-convective-transportive energy balance model of a gray atmosphere to examine individual roles of the greenhouse effect of water vapor,vertical convection,and atmospheric poleward energy transport as well as their combined effects for a quasi-linear relationship between the outgoing longwave radiation(OLR)and surface temperature(T_(S)).The greenhouse effect of water vapor enhances the meridional gradient of surface temperature,thereby directly contributing to a quasi-linear OLR-T_(S) relationship.The atmospheric poleward energy transport decreases the meridional gradient of surface temperature.As a result of the poleward energy transport,tropical(high-latitude)atmosphere-surface columns emit less(more)OLR than the solar energy input at their respective locations,causing a substantial reduction of the meridional gradient of the OLR.The combined effect of reducing the meridional gradients of both OLR and surface temperature by the poleward energy transport also contributes to the quasi-linear OLR-T_(S) relationship.Vertical convective energy transport reduces the meridional gradient of surface temperature without affecting the meridional gradient of OLR,thereby suppressing part of the reduction to the increasing rate of OLR with surface temperature by the greenhouse effect of water vapor and poleward energy transport.Because of the nature of the energy balance in the climate system,such a quasi-linear relationship is also a good approximation for the relationship between the annual-mean net downward solar energy flux at the top of the atmosphere and surface temperature.展开更多
In the age of rapidly growing global population and escalating energy demands,the pursuit of sustainable,zero-emission energy sources has become critical.This article explores the interplay between environmental conce...In the age of rapidly growing global population and escalating energy demands,the pursuit of sustainable,zero-emission energy sources has become critical.This article explores the interplay between environmental concerns,such as global warming and the greenhouse effect,and the need for innovative energy solutions.The melting polar ice caps exemplify the urgent need for reducing carbon emissions.ARCs(advanced reactor concepts)in both fission and fusion technologies offer promising paths to zero-emission energy.Advanced fission reactors,including SMRs(small modular reactors)and Generation IV reactors,provide improved safety,efficiency,and waste management.Fusion energy,despite being in the experimental stage,holds potential as a nearly limitless clean energy source.AI(artificial intelligence)significantly enhances these technologies by optimizing design,operations,maintenance,safety,and grid integration.AI-driven innovations are pivotal in accelerating the development and deployment of ARC technologies,ensuring they are safe,reliable,and efficient.The article underscores the vital role of policy support,global cooperation,and strategic investments in shaping a sustainable energy future that can mitigate the effects of climate change,support economic growth,and protect our planet.展开更多
This study determines if there is a correlation between rising carbon dioxide levels and global warming. Historical data were reviewed from three different time periods spanning 500 million years. It showed that the c...This study determines if there is a correlation between rising carbon dioxide levels and global warming. Historical data were reviewed from three different time periods spanning 500 million years. It showed that the curves and trends were too dissimilar to establish a connection. Observations from CO<sub>2</sub>/temp ratios showed that the CO<sub>2</sub> and the temperature moved in opposite directions 42% of the time. Many ratios displayed zero or near zero values, reflecting a lack of response. As much as 87% of the ratios revealed negative or near zero values, which strongly negate a correlation. The infrared spectra showed the Greenhouse Gases had an exceptionally low absorption band between 11.67 μm to 9.1 μm, which is a zone called the infrared atmospheric window. Most of the Greenhouse Gases absorb little infrared inside that zone. And that zone is where the Earth’s surface emits almost all infrared radiation. Even with minimal absorbance, water vapor captures the most infrared radiation. It absorbs 84 times more than CO<sub>2</sub>, 407 thousand times more than methane, 452 thousand times more than ozone and 2.3 million times more than nitrous oxide. The Intergovernmental Panel on Climate Change (IPCC) and the United States EPA excluded water vapor because it was not associated with man-made activities. They reported that water vapor and clouds were simply feedback mechanisms from CO<sub>2</sub>. Clouds reflect radiation from the sun. The Northern Hemisphere is 2.7°F warmer than the Southern Hemisphere because of clouds. The world cloud cover has gone down 4.1% from 1982 to 2018. Calculations show that this could be responsible for 2.4°F of the 2.7°F. The research shows that most of the recent increase in temperature (89.9%) is because of fewer clouds.展开更多
Effects of aerosol with focus on the direct climate effect of anthropogenic sulfate aerosol under 2×CO2 condition were investigated by introducing aerosol distribution into the latest version of RegCM2. Two exper...Effects of aerosol with focus on the direct climate effect of anthropogenic sulfate aerosol under 2×CO2 condition were investigated by introducing aerosol distribution into the latest version of RegCM2. Two experiments, first run (2×CO2 + 0 aerosol concentration) and second run (2×CO2 + aerosol distribution), were made for 5 years respectively. Preliminary analysis shows that the direct climate effect of aerosol might cause a decrease of surface air temperature. The decrease might be larger in winter and in South China. The regional-averaged monthly precipitation might also decrease in most of the months due to the effect. The annual mean change of precipitation might be a decrease in East and an increase in West China. But the changes of both temperature and precipitation simulated were much smaller as compared to the greenhouse effect.展开更多
A coastal historical evolution of the Yangtze River Delta was discussed in this paper on the basis of the historical data of the coastal zone and an estimation was made for the future change of the coast The emphasi...A coastal historical evolution of the Yangtze River Delta was discussed in this paper on the basis of the historical data of the coastal zone and an estimation was made for the future change of the coast The emphasis was put on the future climate change that will have influence on the sea wall, coastal navigation and freshwater resources in the Delta It was also pointed out that the global warming and precipitation increase in the Yangtze River Valley may exert more impact on the zone In addition, some measures describing how to adapt to the climate change and reduce its impact were put forward展开更多
The solar radiation that hits the Earth conditions the dynamic equilibrium that prevails on our planet. Consideration of basic physical-chemical knowledge shows that this equilibrium can be changed only by additional ...The solar radiation that hits the Earth conditions the dynamic equilibrium that prevails on our planet. Consideration of basic physical-chemical knowledge shows that this equilibrium can be changed only by additional energy input or prolongation of the interaction time solar radiation—Earth matter. The contribution of H<sub>2</sub>O(g) and CO<sub>2</sub> to the protection of the earth against excessive warming is experimentally and by basic laws of nature secured. For a greenhouse effect, a part of the earth radiation must be radiated back to the earth and then into space. If one understands the earth radiation as radiation of a black body with the average global environmental temperature, from all vibrations normal modes of the gases H<sub>2</sub>O(g) and CO<sub>2</sub> only the bending mode of CO<sub>2</sub> with 4% of the solar constant can contribute beside the rotational modes of the water to the greenhouse effect. The contributions of the normal modes of H<sub>2</sub>O(g) and CO<sub>2</sub> to the heat capacity of the atmosphere are negligible. Therefore, in agreement with studies by K. Ångström, CO<sub>2</sub> contributes only to the stabilization of the global environmental temperature. Whether the use of renewable energies can actually at least mitigate the increase of the environmental temperature is by no means certain but must be examined for each individual case. With certainty, this goal can only be achieved by reducing the energy consumption of mankind.展开更多
文摘The analysis of Greenhouse Effect experiments in the public domain indicated that the lab tests were primarily centered around illustrating the mechanics of conventional greenhouses. They used high-energy visible light (such as sunlight), rather than addressing the Greenhouse Effect, which involves low-energy infrared radiation emitted by the Earth’s surface. Studies with argon, a non-greenhouse gas with similar density to CO2, showed thermal heat transfer as the dominant factor in the temperature profiles, with radiation absorption being undetected. The same conclusion was drawn by another study, which measured infrared back radiation. Experiments using exaggerated CO2 concentrations inadvertently illustrated the principle of the Popper Falsification Test by disproving the Greenhouse Effect applicable to CO2 within the troposphere. A straightforward kitchen test showed that a microwave oven cannot be used as a model for the Greenhouse Effect.
文摘Before there were humans, the world changed only slowly. The climate warmed and cooled, new plants and animals developed and became extinct (绝灭的) in their turn, and sea level rose and fell over periods of thousands, if not millions of years. But during the last two thousand years great changes have taken place. Forests have disap-
基金This research was supported by National Key Programme for Developing Basic Sciences(G1998040900 - Part I) Chinese Academy of
文摘Impacts of greenhouse effects (2 × CO2) upon climate change over China as simulated by a regional climate model over China (RegCM / China) have been investigated. The model was based on RegCM2 and was nested to a global coupled ocean-atmosphere model (CSIRO R21L9 AOGCM model). Results of the control run (1 × CO2) indicated that simulations of surface air temperature and precipitation in China by RegCM are much better than that by the global coupled model because of a higher resolution. Results of sensitive experiment by RegCM with 2 × CO2 showed that the surface air temperature over China might increase remarkably due to greenhouse effect, especially in winter season and in North China. Precipitation might also increase in most parts of China due to the CO2 doubling. Key words Regional climate model - Greenhouse effect This research was supported by National Key Programme for Developing Basic Sciences (G1998040900 — Part I), Chinese Academy of Sciences Key Program KZCX2-203 and KZ981-B1-108.
文摘We mainly discuss changes of precipitation in China due to growinggreenhouse gases using GCM1 model assuming the IPCC 'Business-as-Usual'Scenario. An increasing greenhouse effect will lead to precipitation increasesmostly in north of 30°N for winter, and strongly increases alap a slant belt fromNortheast China to Bay of Bangal for summer in China. The mp of increasingprecipitation are about 7.9, -0.7 and 13.6 percent for winter, and 6.4, 12.9 and 8.4percent for summer m China, Changjinang and Huanghe river valleys, respectively.The model results are also shown to imply that an increasing greenhouse effectenhances chanas of intense storms and shown for winter and summer in China.
文摘An obvious warming in China induced by doubled carbon, dioxide as simulated by the climatic models have been found. It is also noticed that there might be drying or wetting in some parts of China induced by doubled CO2 as simulated by the general circulation models(GCMs). Agricultural productivity mainly depends on the temperature, rainfall and soil moisture in China. The changes of agricultural productivity in the different parts of China induced by doubled CO2 have been estimated in this paper. It is shown that the greenhouse effect might cause increasing production in some parts of China and decreasing production in other parts of China.
文摘The physical processes associated with the clear-sky greenhouse effect in the presence of water vapor are examined by including surface emissivity in the greenhouse effect formulation, and by introducing a new way to partition physical processes of the greenhouse effect. In this new framework, it is found that the clear-sky greenhouse effect is governed by three physical processes associated with (1) the temperature contrast between the surface and the atmosphere, (2) the interaction between the surface emissivity and the temperature contrast, and (3) the surface emissivity. The importance of the three physical processes is assessed by computing their vertical and spectral variations far the subarctic winter and summer standard atmosphere using the radiation model MODTRAN3 (Moderate Resolution Transmittance code Version 3). The results show that the process associated with the temperature contrast between the surface and the atmosphere dominates over the other two processes in magnitude. The magnitude of this process has substantial variations in the spectral region of 1250 to 1880 cm-1 and in the far infrared region. Due to the low-level temperature inversion over the subarctic winter, there exists a negative contribution to the greenhouse trapping. The seasonal variations are, however, dominated by the processes associated with the interaction between the surface emissivity and the temperature contrast as well as the surface emissivity itself. The magnitudes of these two physical processes contributing to the greenhouse trapping over the subarctic winter are about 7 to 10 times of those over the subarctic summer, whereas the magnitude of the processes associated with the temperature contrast in the subarctic summer is only about 2 times of that in the subarctic winter.
文摘Climatic changes can be separated into two parts: natural changes -and human activity influenced on climatic changes. The observed data could not only show the effects caused by human activity. Several simulated results as simulated by the GCMs induced by the greenhouse effects in China .have been analysed. It is shown that an obvious warming of about 3-6℃ in winter and 2-5℃ in summer in China as simulated by the GCMs induced by doubling CO2 have been found. There are getting drier or wetter regions in China due to doubled CO2 as simulated by most of models. Comparing the simulated results with the observed data in China, some simulated results are able to be believed. The GCMs should be improved, especially in the regional areas.
文摘In carbon global cycle, the relationship between the terrestrial ecosystem and the atmosphere where there are, among others, gases that contribute to the greenhouse effect, has become object of relevant scientific interest. The content of organic matter in soil, expressed by its supplies as well as the organic matter degree of stability, are factors that can prevent the soil from acting as a drain and at the same time contribute for it to become a source of those gases. The variations in the way land is used in Brazil are factors responsible for the increase in emission of greenhouse effect gases. Based on these facts, this study was aimed to evaluate the CO2 and CH4 efflux using a gas retention chamber, and to associate these emissions to the organic carbon content in the soil. Two different areas were selected for the study, one in Tijuca Forest National Park, in a forest area, and the other at the Rio de Janeiro Federal Rural University campus. In the latter, the area was stratified in three sub areas according to the vegetation, use and water saturation degree. Samplings were performed during 8 months between 2013 and 2014.
文摘Over the past two years, the food culture of the small town of Agarfa in south Ethiopia has seen some tasty changes. Tomatoes, previously unaffordable to all but the very wealthy, have become a common sight on the plates of local people. The secret lies in the introduction of greenhouse tomato growing technology.
基金the National Natural Science Foundation of China under Grant 40231005Major Research Program for Global Change and Response+1 种基金the National Natural Science Foundation of China under Grant 40125014the fund for IPCC of China Meteorological Administration
文摘Impacts of greenhouse effects (2×CO_2) on climate change over China as simulated by a regional climate model have been investigated.The model was based on RegCM2 and is nested in one-way mode within a global coupled atmosphere-ocean model (CSIRO R21L9 AOGCM).Two multi-year simulations,the control run with normal CO_2 concentration and sensitivity run with doubled CO_2 concentration are conducted. As Part II of the publications,with a brief analysis of the 2×CO_2 experiment by CSIRO R21Lg,results of the 2×CO_2 simulation by RegCM2 are analyzed in detail. Results of the RegCM show a remarkably warming over China with an increment ranging from 2.2℃ in southern China to 2.8℃ in northern due to greenhouse effect.The regional averaged annual temperature increase is 2.5℃.The warming is greater in winter and spring.Daily maximum and minimum temperatures increase also over China which lead to much more hot spell days in summer and less cold spell days in winter. Precipitation increases in all seasons of the year,with the greatest found in summer.Annual mean precipitation increases significantly in western China,parts of the area in south of the Yangtze River and northern part of the Northeast.while a decrease in the area from southern part of the Northeast to North China is simulated.The regional averaged annual increase of precipitation is 12%.More heavy rain events are found noticeably in southern China.The simulated tropical storms affecting and landing over China tend to increase.Analysis on the simulation of circulation pattern showed that the 500 hPa height in East Asia might rise significantly.
基金This work was supported by the National Natural Science Foundation of China(NSFC)(Grant No.41871343).
文摘Accurate measurements of the three-dimensional structure characteristics of urban buildings and their greenhouse effect are important for evaluating the impact of urbanization on the radiation energy budget and research on the urban heat island(UHI)effect.The decrease in evapotranspiration or the increase in sensible heat caused by urbanization is considered to be the main cause of the UHI effect,but little is known about the influence of the main factor“net radiant flux”of the urban surface heat balance.In this study,experimental observation and quantitative model simulation were used to find that with the increase of building surface area after urbanization,the direct solar radiation flux and net radiation flux on building surface areas changed significantly.In order to accurately quantify the relationship between the positive and negative effects,this study puts forward the equivalent calculation principle of“aggregation element”,which is composed of a building’s sunny face and its shadow face,and the algorithm of the contribution of the area to thermal effect.This research clarifies the greenhouse effect of a building with walls of glass windows.Research shows that when the difference between absorption rates of a concrete wall and grass is−0.21,the cooling effect is shown.In the case of concrete walls with glass windows,the difference between absorption rates of a building wall and grass is−0.11,which is also a cooling effect.The greenhouse effect value of a building with glass windows reduces the cooling effect value to 56%of the effect of a building with concrete walls.The simulation of changes in net radiant flux and flux density shows that the greenhouse effect of a 5-story building with windows yields 15.5%less cooling effect than one with concrete walls,and a 30-story building with windows reduces the cooling effect by 23.0%.The simulation results confirmed that the difference in the equivalent absorption rate of the aggregation element is the“director”of cooling and heating effects,and the area of the aggregation element is the“amplifier”of cooling and heating effects.At the same time,the simulation results prove the greenhouse effect of glass windows,which significantly reduces the cold effect of concrete wall buildings.The model reveals the real contribution of optimized urban design to mitigating UHI and building a comfortable environment where there is no atmospheric circulation.
文摘This paper describes a diagnostic study of the feedback mechanism in greenhouse effects of increased CO_2 and oth- er trace gases(CH_4,N_2O and CFCs),simulated by general circulation model.The study is based on two sensitivity exper- iments for doubled CO_2 and the inclusion of other trace gases,respectively,using version one of the community climate model(CCM1)developed at the National Centre for Atmospheric Research.A one-dimensional(1-D)and a two-dimensional(2-D)radiative-convective models are used to diagnose the feedback effect.It shows that the feedback factors in global and annual mean conditions are in the sequence of surface albedo,water vapor amount,water vapor distribution,cloud height,critical lapse rate and cloud cover,while in zonal and annual mean conditions in the tropical region the above sequence does not change except the two water vapor terms being the largest feedback compo- nents.Among the feedback components,the total water vapor feedback is the largest(about 50%).The diagnosis also gives a very small feedback of either the cloud cover or the lapse rate,which is substantially different from the 1-D feedback analysis by Hansen et al.(1984).The small lapse rate feedback is considered to be partly caused by the convective adjustment scheme adopted by CCM1 model. The feedback effect for doubled CO_2 is very different from that of the addition of other trace gases because of their different vertical distributions of radiative forcing although the non-feedback responses of surface air temperature for both cases are almost the same.For instance,the larger forcing at surface by the addition of other trace gases can cause stronger surface albedo feedback than by doubled CO_2.Besides,because of the negative forcing of doubled CO_2 in the stratosphere,cloud height feedback is more intense.The larger surface forcing in the case of other trace gases can also in- fluence atmospheric water vapor amount as well as the water vapor distribution,which will in turn have stronger feedback effects.All these indicate that it is incorrect to use“effective CO_2”to replace other trace gases in the general circulation model.
文摘Two one-dimensional radiative-convective models with the same scheme and the different ranges that one is from surface to stratopause and the other is from surface to tropopause,have been developed to study the role played by the stratosphere in greenhouse effect.It is shown that the addition of stratospheric response may lead to an increase of 7—50 percent in radiative forcing at the tropopause,and an increase of 20—60 percent in surface temperature when the con- centration of the same gas in the two models increases at the same time;and when the same change in radiative forcing at the tropopause due to the same agent in the two models occurs,the addition of stratospheric response may lead to an in- crease of 5—20 percent in surface temperature;and allowing for the stratospheric adjustment means that the tempera- ture responses to the same flux change due to different causes are in far disagreement.
基金The paper is written to the memory of Dr.Tu Changwang(1906-1962),one of the founders for modern meteorology of China.
文摘The global mean temperatures of the atmosphere and the surface of various planets of the solar system are deter- mined by taking the system as in radiative equilibrium,with the atmosphere taken as transparent to solar radiation but with an albedo α,and composed of N layers each of which absorbs all infrared radiation that falls on it,and a top layer of partial absorptivity a,while the surface is taken as black.It is found that,for the earth's atmosphere with α=0.33, N=0,a=0.83,it gives the current observed mean surface temperature T_s=15℃ and the effective mean radiative temper- ature of the atmosphere T_a=242.6K.On the other hand;the atmosphere of Venus is characterized by α=0.70 and N=70,which yields a surface temperature of about 700K. It is also found that surface evaporation and absorption of solar radiation by the atmosphere tend to lower the sur- face temperature.
基金part supported by grants from the National Natural Science Foundation of China(Grant Nos.42222502 and 42075028)grants from the National Science Foundation(AGS-2032542 and AGS-2202875)。
文摘In this study,we put forward a radiative-convective-transportive energy balance model of a gray atmosphere to examine individual roles of the greenhouse effect of water vapor,vertical convection,and atmospheric poleward energy transport as well as their combined effects for a quasi-linear relationship between the outgoing longwave radiation(OLR)and surface temperature(T_(S)).The greenhouse effect of water vapor enhances the meridional gradient of surface temperature,thereby directly contributing to a quasi-linear OLR-T_(S) relationship.The atmospheric poleward energy transport decreases the meridional gradient of surface temperature.As a result of the poleward energy transport,tropical(high-latitude)atmosphere-surface columns emit less(more)OLR than the solar energy input at their respective locations,causing a substantial reduction of the meridional gradient of the OLR.The combined effect of reducing the meridional gradients of both OLR and surface temperature by the poleward energy transport also contributes to the quasi-linear OLR-T_(S) relationship.Vertical convective energy transport reduces the meridional gradient of surface temperature without affecting the meridional gradient of OLR,thereby suppressing part of the reduction to the increasing rate of OLR with surface temperature by the greenhouse effect of water vapor and poleward energy transport.Because of the nature of the energy balance in the climate system,such a quasi-linear relationship is also a good approximation for the relationship between the annual-mean net downward solar energy flux at the top of the atmosphere and surface temperature.
文摘In the age of rapidly growing global population and escalating energy demands,the pursuit of sustainable,zero-emission energy sources has become critical.This article explores the interplay between environmental concerns,such as global warming and the greenhouse effect,and the need for innovative energy solutions.The melting polar ice caps exemplify the urgent need for reducing carbon emissions.ARCs(advanced reactor concepts)in both fission and fusion technologies offer promising paths to zero-emission energy.Advanced fission reactors,including SMRs(small modular reactors)and Generation IV reactors,provide improved safety,efficiency,and waste management.Fusion energy,despite being in the experimental stage,holds potential as a nearly limitless clean energy source.AI(artificial intelligence)significantly enhances these technologies by optimizing design,operations,maintenance,safety,and grid integration.AI-driven innovations are pivotal in accelerating the development and deployment of ARC technologies,ensuring they are safe,reliable,and efficient.The article underscores the vital role of policy support,global cooperation,and strategic investments in shaping a sustainable energy future that can mitigate the effects of climate change,support economic growth,and protect our planet.
文摘This study determines if there is a correlation between rising carbon dioxide levels and global warming. Historical data were reviewed from three different time periods spanning 500 million years. It showed that the curves and trends were too dissimilar to establish a connection. Observations from CO<sub>2</sub>/temp ratios showed that the CO<sub>2</sub> and the temperature moved in opposite directions 42% of the time. Many ratios displayed zero or near zero values, reflecting a lack of response. As much as 87% of the ratios revealed negative or near zero values, which strongly negate a correlation. The infrared spectra showed the Greenhouse Gases had an exceptionally low absorption band between 11.67 μm to 9.1 μm, which is a zone called the infrared atmospheric window. Most of the Greenhouse Gases absorb little infrared inside that zone. And that zone is where the Earth’s surface emits almost all infrared radiation. Even with minimal absorbance, water vapor captures the most infrared radiation. It absorbs 84 times more than CO<sub>2</sub>, 407 thousand times more than methane, 452 thousand times more than ozone and 2.3 million times more than nitrous oxide. The Intergovernmental Panel on Climate Change (IPCC) and the United States EPA excluded water vapor because it was not associated with man-made activities. They reported that water vapor and clouds were simply feedback mechanisms from CO<sub>2</sub>. Clouds reflect radiation from the sun. The Northern Hemisphere is 2.7°F warmer than the Southern Hemisphere because of clouds. The world cloud cover has gone down 4.1% from 1982 to 2018. Calculations show that this could be responsible for 2.4°F of the 2.7°F. The research shows that most of the recent increase in temperature (89.9%) is because of fewer clouds.
基金National Natural Science Fundamental of China (40125014) Knowledge Innovation Program of the Chinese Academy of Sciences (KZCX1-SW-01-16) Supporting Fund for IPCC of China Meteorological Administration
文摘Effects of aerosol with focus on the direct climate effect of anthropogenic sulfate aerosol under 2×CO2 condition were investigated by introducing aerosol distribution into the latest version of RegCM2. Two experiments, first run (2×CO2 + 0 aerosol concentration) and second run (2×CO2 + aerosol distribution), were made for 5 years respectively. Preliminary analysis shows that the direct climate effect of aerosol might cause a decrease of surface air temperature. The decrease might be larger in winter and in South China. The regional-averaged monthly precipitation might also decrease in most of the months due to the effect. The annual mean change of precipitation might be a decrease in East and an increase in West China. But the changes of both temperature and precipitation simulated were much smaller as compared to the greenhouse effect.
文摘A coastal historical evolution of the Yangtze River Delta was discussed in this paper on the basis of the historical data of the coastal zone and an estimation was made for the future change of the coast The emphasis was put on the future climate change that will have influence on the sea wall, coastal navigation and freshwater resources in the Delta It was also pointed out that the global warming and precipitation increase in the Yangtze River Valley may exert more impact on the zone In addition, some measures describing how to adapt to the climate change and reduce its impact were put forward
文摘The solar radiation that hits the Earth conditions the dynamic equilibrium that prevails on our planet. Consideration of basic physical-chemical knowledge shows that this equilibrium can be changed only by additional energy input or prolongation of the interaction time solar radiation—Earth matter. The contribution of H<sub>2</sub>O(g) and CO<sub>2</sub> to the protection of the earth against excessive warming is experimentally and by basic laws of nature secured. For a greenhouse effect, a part of the earth radiation must be radiated back to the earth and then into space. If one understands the earth radiation as radiation of a black body with the average global environmental temperature, from all vibrations normal modes of the gases H<sub>2</sub>O(g) and CO<sub>2</sub> only the bending mode of CO<sub>2</sub> with 4% of the solar constant can contribute beside the rotational modes of the water to the greenhouse effect. The contributions of the normal modes of H<sub>2</sub>O(g) and CO<sub>2</sub> to the heat capacity of the atmosphere are negligible. Therefore, in agreement with studies by K. Ångström, CO<sub>2</sub> contributes only to the stabilization of the global environmental temperature. Whether the use of renewable energies can actually at least mitigate the increase of the environmental temperature is by no means certain but must be examined for each individual case. With certainty, this goal can only be achieved by reducing the energy consumption of mankind.