Increase In Atmospheric Temperature Research Articles

Effect of cooling water loop on the thermal performance of air conditioning system

The aim of this research is to improve thermal performance of air conditioning system by cooling water loop. In experiment, the cooling water loop with the concentric helically coiled tube heat exchanger is installed between the compressor unit and condenser unit for cooling refrigerant before entering the condenser unit. Effects of water mass flow rate and atmospheric temperature on the COP are considered. The obtained results are compared with those from the conventional air conditioning system without cooling water loop. It can be seen that the COP tends to increase with increasing water mass flow rate and tend to decrease as atmospheric temperature increases. The highest COP is 31.02% as compared with the conventional reference system, respectively. In addition, not only COP of air conditioning system are increased but also the hot water storage is obtained which used for various applications. The results obtained this study are expected to lead to guidelines that will allow the improved thermal performance of air conditioning system and hot water storage system which reduce energy consumption.

The effects of a moderate grape temperature increase on berry secondary metabolites

Context and purpose of the study: Like in other wine producing regions around the world, Bordeaux vineyards already experience the effects of climate change. Recent trends as well as model outputs for the future strongly support an increase of average and extreme temperatures. For the maturation period, this increase will by far exceed mean atmospheric temperature increase, as the ripening period will occur earlier in hotter climatic conditions. Therefore, a detrimental secondary metabolism response is expected in grape berries, and of particular concern are the impacts on phenolics and aromas and aroma precursors. The effects of high temperatures on secondary metabolism control have been partly characterized for phenolics, however mostly in artificial growing conditions, while little is known with respect to aromas. A better understanding of how high temperatures influence grape berry secondary metabolites could help vineyard growers to adapt to climate change and maintain wine quality.Material and methods: A two-year field study was carried out in 2015 and 2016 in a vineyard in Bordeaux, France. Two treatments, heated (H) and control (C), were applied to two varieties, Cabernet-Sauvignon and Sauvignon blanc, from fruit-set to maturity. Field heating was achieved by a very local greenhouse effect applied to the bottom of the rows, by enclosing most of the underlying soil surface by polycarbonate shields. As the training system was vertically trellised, the heated volume surrounded most of the bunches but did not disturb most of the leaves in the canopy. This simple and robust setup allowed an increase of berry temperature by about +1.5°C in mean value, up to +5°C at times during clear sky days. This moderate increase of temperature was indicative of the predicted future climatic conditions for the mid-21st century. Berry samples were collected at 4 time points from bunch closure to maturity for each cultivar and treatment. Primary and secondary metabolites were measured in whole berries or skins.Results and conclusions: With this moderate temperature increase, primary metabolite content in berries did not change significantly. In H samples, anthocyanins were reduced and tannins increased before veraison, and both decreased thereafter. H samples also exhibited lower concentrations of some amino acids, especially alanine, serine and phenylalanine. IBMP (2-methoxy-3-isobutylpyrazine) concentrations were also reduced in H samples of Cabernet-Sauvignon, in both seasons, especially at bunch closure stage, but the differences diminished at full maturity. For thiol 3-sulfanyl hexanol precursors, H samples again exhibited much lower concentrations for both varieties, with weak differences at early stages that increased at later stages (up to -70% decline at maturity in 2015 for Sauvignon blanc). These results demonstrate the potential negative impact of elevated temperature on polyphenols and aroma quality of grape berries.Significance and impact of the study: For viticulture to adapt to new climatic conditions, the negative impacts of high temperature on secondary metabolites and aromas, and therefore on wine quality, need to be contemplated. Thus, already established or new vineyard plantings must prepare and consider practices able to mitigate these impacts, for instance practices that increase bunch shading.

Apparent temperature sensitivity of soil respiration can result from temperature driven changes in microbial biomass

The ongoing increase of atmospheric temperature may induce soil organic carbon (SOC) loss and exacerbate the greenhouse effect. As a result, there is a great effort to understand the relationship between temperature and the heterotrophic soil respiration rate (RSOIL) as it has significant implications for anticipated change of the Earth system. Soil respiration depends on the size of respiring microbial biomass (MBC) and when RSOIL is measured without concurrent measurement of MBC, the apparent temperature sensitivity of RSOIL could be misinterpreted since MBC can change with temperature within days or weeks of warming. The effect of temperature driven changes in MBC on the apparent temperature sensitivity of RSOIL was evaluated using a meta-analysis of 27 laboratory and field experiments conducted at different temporal scales (1–730 d) and under a wide range of temperatures (2–50 °C) and soil conditions. Across all studies, the apparent temperature sensitivity decreased when MBC decreased with increasing temperature and vice versa. We observed a steep decrease of MBC above optimal temperature (27.1 ± 1.0 °C), which attenuated the apparent temperature sensitivity of RSOIL, an aspect previously explained by the existence of reaction rate temperature optima. The temperature response of the MBC specific respiration rate was, however, highly non-linear and soil specific. Including MBC in soil biogeochemical models requires careful consideration of the variability of temperature-associated physiological changes of soil microorganisms. Without it, microbially explicit models cannot predict temperature induced SOC loss better than older, empirical models based on first order reaction kinetics.

Research on the performance improvement of a two-shaft gas turbine with a variable area nozzle power turbine

Both an increase in atmospheric temperature and a decrease in atmospheric pressure can lead to the degradation of the maximum allowable power output (MAPO) or the thermal efficiency of a gas turbine. In order to reduce these adverse effects, this paper provides a simulated study on the improvement of the MAPO and the variations of the thermal efficiency due to the fuel flow and variable area nozzle control under different atmospheric conditions. Simulation results indicate that the MAPO increases with the power turbine nozzle area, while the thermal efficiency shows a parabola trend. With the same increment of the power turbine nozzle area, the improvement of the MAPO goes up as the atmospheric temperature rises and the decrease of thermal efficiency is alleviated. Analyses show that the slow degradation of the compressor isentropic efficiency is a key factor that enables the MAPO to increase significantly and the thermal efficiency to remain almost constant.

Study on the active phase formation of Pd-Zn/Sibunit catalysts during the thermal treatment in hydrogen

In the present research, the process of the formation of the active components of Pd-Zn catalysts supported on carbonaceous material Sibunit prepared by the joint impregnation (Pd:Zn = 1) is studied. It was shown by means of TPR and EXAFS techniques that the interaction between palladium and zinc begins already at T > 200 °C. During the reduction in hydrogen at temperatures of 200–300 °C the surface of particles being formed is enriched with oxidized zinc. In the temperature range of 400–500 °C zinc is completely reduced, and the crystal lattice of a substitutional solid solution based on fcc lattice of palladium is restructured in tetragonal lattice of PdZn. However, an increase of the calcination temperature in H2 atmosphere (500 °C) significantly rises up the probability of partial destruction of bimetallic phase due to the partial migration of zinc atoms from the surface into the bulk of particles.

Concentration variation and law of greenhouse gases in Xining

Greenhouse gas means which can absorb reflection of solar radiation on the ground and re-emit some radiation, such as water vapor, carbon dioxide (CO2), methane (CH4), most refrigerants, etc. Greenhouse gases can cause the greenhouse effect, and lead to the increase of atmospheric temperature. Although most of the greenhouse gases are relatively stable in the air, it can impact on the atmospheric environment, and then affect the environment chemical reactions in the air and rust in atmospheric pollution. Xining, as a one of the major cities in Qinghai-Tibet Plateau, it is important to study the concentration variation and law of greenhouse gases.

Concentration variation and law of greenhouse gases in National Station for Background Atmospheric Monitoring, Menyuan, Qinghai, China and compare with Xining

Greenhouse gas means which can absorb reflection of solar radiation on the ground and re-emit some radiation, such as water vapor, carbon dioxide (CO2), methane (CH4), most refrigerants, etc. Greenhouse gases can cause the greenhouse effect, and lead to the increase of atmospheric temperature. Although most of the greenhouse gases are relatively stable in the air, it can impact on the atmospheric environment, and then affect the environment chemical reactions in the air and rust in atmospheric pollution.

Variations in the intrinsic water-use efficiency of north Patagonian forests under a present climate change scenario: tree age, site conditions and long-term environmental effects.

The carbon isotope composition (δ13C) in tree rings were used to derive the intrinsic water-use efficiency (iWUE) of Araucaria araucana trees of northern Patagonia along a strong precipitation gradient. It is well known that climatic and ontogenetic factors affect growth performance of this species but little is known about their influence in the physiological responses, as iWUE. Thus, the main objective of this study was to assess the physiological reactions of young and adult trees from two open xeric and two moderately dense mesic A. araucana forests to the increases in atmospheric CO2 (Ca) and air temperature during the 20th century, and to relate these responses with radial tree growth. The results indicated that the iWUE and the intercellular CO2 concentration (Ci) increased 33% and 32% in average during the last century, respectively, but carbon isotope discrimination (∆13C) was more variable between sites and age classes. Trees from xeric sites presented greater iWUE and lower ∆13C and Ci values than those from mesic sites. In general, iWUE was strongly related with Ca and was significantly affected by mean summer maximum temperature. ∆13C from mesic sites seemed to be mainly affected by summer maximum temperature, while trees from xeric conditions did not show any influence. Tree age also presented a significant effect on iWUE. Adult trees showed higher iWUE values than young trees, indicating an incidence of the tree age and/or height, mainly in closed mesic forests. Moreover, some trees presented positive relationships between iWUE and radial tree growth, while others presented negative or no relationships, indicating that other factors may negatively influence tree growth. Broadly, the results demonstrate the incidence of climatic, environmental and ontogenetic variability in the tree responses; however, more studies are needed to better understand which forests will be more affected by actual and future climate changes.

Do climate changes alter the distribution and transmission of malaria? Evidence assessment and recommendations for future studies.

Malaria, a mosquito-borne infectious disease, is considered a significant global health burden. Climate changes or different weather conditions may impact infectious diseases, specifically those transmitted by insect vectors and contaminated water. Based on the current predictions for climate change associated with the increase in carbon dioxide concentrations in the atmosphere and the increase in atmospheric temperature, the Intergovernmental Panel on Climate Change predicts that in 2050, malaria may threaten some previously unexposed areas worldwide and cause a 50% higher probability of malaria cases. Climate-based distribution models of malaria depict an increase in the geographic distribution of the disease as global environmental temperatures and conditions worsen. Researchers have studied the influence of changes in climate on the prevalence of malaria using different mathematical models that consider different variables and predict the conditions for malaria distribution. In this context, we conducted a mini-review to elucidate the important aspects described in the literature on the influence of climate change in the distribution and transmission of malaria. It is important to develop possible risk management strategies and enhance the surveillance system enhanced even in currently malaria-free areas predicted to experience malaria in the future.

Statistical Modeling of Emission Factors of Fossil Fuels Contributing to Atmospheric Carbon Dioxide in Africa

Global warming is majorly caused by an increase in atmospheric temperature and carbon dioxide (CO2) emissions due to the rise in the temperature. The continued accumulation of CO2 into the atmosphere is a massive part of the climate change problem. This study aims to develop a data-driven statistical model using Africa’s fossil-fuel CO2 emissions real data to identify the significant attributable variables and their interaction that produce the carbon dioxide emissions. However, we have considered five attributable variables in our statistical modeling and they are Liquid fuels (Li), Solid fuels (So), Gas fuels (Ga), Gas flares (Gf) and Cement production. The development of the statistical model that contains the different emissions of fossil fuels and their interactions have been specified and ranked based on a percentage of their annual contributions to carbon dioxide in the atmosphere. Our proposed statistical model is compared with a different penalization method since multicollinearity among the risk factors exists and which provided excellent results according to the root mean square errors (RMSE) statistic. The results of the proposed model are compared to previous results of different countries of the world.

Correlation between heliogeophysical factors and osmotic pressure of blood plasma in patients with arterial hypertension with different temperament

The relation between heliogeophysical factors and the osmotic pressure of blood plasma in patients with arterial hypertension with different temperaments is analyzed. It is found that with increasing solar activity (Wolf numbers and radio flux wavelength 10,7 cm), is closely related increase in atmospheric pressure, air temperature and γ-background (within normal limits) in the workplace examinees. It was revealed that in choleric and sanguine patients there is a reliable high inverse correlation relationship between heliogeophysical, meteorological factors and total peripheral vascular resistance, while the phlegmatic and melancholic - the average direct and direct high correlation relationship. Antihypertensive therapy with diuretics with increased solar activity, combined with an increase in the atmospheric pressure, γ-background and the air temperature in the workplace, due a decrease in total peripheral vascular resistance at the choleric and sanguine and increase in total peripheral vascular resistance in healthy individuals and phlegmatic patients and melancholic. The presence of significant and reverse correlation relationship between the total peripheral vascular resistance and osmotic pressure of blood plasma in choleric and sanguine and significant, but a direct correlation - the phlegmatic and melancholic indicates the inclusion of an adaptive process various physiological mechanisms, which determines the need to consider the temperament at solar biospheric relations bonds.

Climate change: impact, and mitigation strategies for tropical and subtropical fruits

Global warming and climate change is the greatest concern of mankind in the 21st century. Climate change is projected to cause an increase in temperature, variations in rainfall, and an increase in frequency of extreme events such as heat, cold waves, frost days, droughts, floods, etc. Various plant processes like vegetative growth, flowering, fruiting and fruit quality are highly vulnerable to climate changes. Two major parameters of climate changes that have far reaching implications on plants are more erratic rainfall patterns and unpredictable high temperature spells which are consequently expected to reduce crop productivity. Drought reduced fruit set and increased fruit cracking in pomegranate and litchi. An increase in atmospheric temperature and change of rainfall pattern affected the banana cultivation in some countries. In various fruit crops, moisture stress and high temperature during flowering strongly influences the pollen and ovule quality and consequently the fruit set and yield. The promotion of stigma and stamen sterility in papaya is mainly because of the higher temperature, which caused flower drops as well as sex changes in female and hermaphrodite flowers. Flower drop is quite common in mango, guava, litchi and other fruits, if low temperature prevails during flowering. Studies have clearly shown that the population abundance, geographic range and pollination activities of important pollinator species like bees, moths, and butterflies are declining considerably with changing climate. Higher temperature during fruit growth and development increased the incidence of several physiological disorders like spongy tissue and black tip in mango, cracking of fruits, granulation in citrus, etc. Pest ecology of certain crops is changing due to climate change. Fruit fly in guava, carambola, citrus, etc. is becoming alarming due to hot and humid conditions. Warm and humid conditions are also favorable for pests like beetles, bugs and other sucking pests and diseases like mildew, blight, etc. Development of new varieties with higher yield potential and resistance to multiple stresses (drought, flood, salinity) should be the key to maintain yield. Improvement in germplasm of important tropical and subtropical fruit crops for heat stress tolerance should be one of the targets of breeding programs. Location specific soil and water conservation models, protocol for organic farming, conservation horticulture, development of biotic and abiotic stress tolerance rootstocks, etc., are some of the strategies to mitigate the impact of climate change. This paper briefly discussed the impact and mitigation strategies of climate change on tropical and subtropical fruits.

Potential Impacts of Climate Variation on Potato Field Evapotranspiration: Field Experiment and Numerical Simulation of Potato Water Use in an Arid Site

AbstractClimate change would significantly affect crop evapotranspiration processes. Many studies have been conducted for various crops. However, there is a lack of sufficient observational evidence on how climate change would influence potato evapotranspiration. In this paper, an experimental potato field in Maowusu Desert, northwest of China, was used to investigate the effect of climate change on potato evapotranspiration. Temporal variations in reference evapotranspiration (ET0) were comprehensively investigated during 1954–2013, which shows that annual temperature and ET0 had significant increasing trends in the past 60 years. Meanwhile, an experimental crop of potato was grown in Maowusu Desert to investigate water‐soil‐air‐plant‐human nexus in 2016, and a HYDRUS‐1D model for the unsaturated flow in a potato field was calibrated and validated with measured soil water tensions and soil water contents at various depths during the potato growing periods from 8 to 16 August 2016 and from 6 September to 3 October 2016, respectively. The model computed the actual potato evapotranspiration (ETa) as 183 mm during the whole growing period from 5 June to 3 October 2016. The groundwater contribution to potato water use was calculated to be 320 mm during the growing season in 2016. As the atmospheric temperature increases, the reference crop evapotranspiration increases, the actual potato evapotranspiration increases too. The actual potato evapotranspiration increase with temperature increase will lead to a bigger water resource pressure in this area. The study results provide the basis for managing crop irrigation in the region in the future.

Significant Space Weather Impact on the Escape of Hydrogen From Mars

AbstractIn September 2017, an active region of the Sun produced a series of strong flares and a coronal mass ejection that swept past Mars producing enhanced ionization and heating in the upper atmosphere. Emissions from atmospheric hydrogen Lyman‐α were also enhanced at Mars. Temperatures derived from neutral species scale heights were used in conjunction with the H Lyman‐α observations to simulate the effects of this space weather event on Martian hydrogen properties in the exosphere. It was found that hydrogen abundance in the upper atmosphere decreased by ~25% and that the H escape rate increased by a factor of 5, mainly through an increase in upper atmospheric temperature. This significant escape rate variation is comparable to seasonally observed trends but occurred at much shorter timescales. Such solar events would statistically impact extrapolation of Martian water loss over time.

Cooling towers performance in a changing climate: Techno-economic modeling and design optimization

This paper presents a model of a natural draft wet type cooling tower, which is based on the conservation laws of thermodynamics. The model assesses the cooling abilities of a tower, the evaporation rate, and the amount of required make-up water, all represented as a function of the atmospheric conditions. The purpose of the model is to estimate the effects of extreme weather conditions on the thermodynamic efficiency of a natural draft wet type cooling tower. World climate is changing and average temperatures are anticipated to rise in the near future, thus affecting the electrical energy generation. To that aim, we study the climate change effects on the ability of natural draft wet type cooling towers to reject heat and hence on the electricity generation of thermal power plants. Additionally, we perform cost-based analyses of a cooling tower considering the long-term projections for air temperature increase, and exemplify our model with reference to a location in France. The results show a remarkable drop in the cooling tower efficiency, and, hence, significant electricity generation losses even when a small increase of atmospheric temperature above the cooling tower design temperature occurs. Furthermore, the results of the cost-based analysis show that large electricity losses are expected. However, the performed cost-based analyses, considering climate change projections, show that even with the highest temperature increase, there is no need for additional tower height. In other words, the concrete costs outweigh the generated revenues from the curtailed power as result of insufficient cooling.

Evaluating millennial to contemporary time scales of glacier change in Val Viola, Central Italian Alps

ABSTRACTTo improve current understanding of ongoing deglaciation dynamics in relation to climatic forcing, it is critical to build long-term series of climate and glacier changes. This task is typically hampered by availability and resolution of Quaternary glacier paleo-reconstructions. To explore opportunities and challenges, we present a case study from Val Viola, which integrates area, volume and ELA changes across a 13k-year time window, including four Younger Dryas–Early Holocene glacier stadials and eight post-LIA periods. Results suggest that relevant shifts in climatic forcing associated with the Pleistocene–Holocene transition and post-LIA deglaciation phases are of comparable magnitude, with an atmospheric temperature increase of about 1.5–2°C. Post-LIA decline in glacierized areas (68.9 ± 6%) is comparable with retreat rates recorded in other Italian glaciers, but is greater than elsewhere in the Alps, where glaciers are comparably larger. Glacier stability in the particularly warm 2007–2015 period testifies to the decoupling attained by small glaciers from synoptic atmospheric conditions. We argue that this is caused by enhanced wind drift and avalanche accumulation, occurred in response to morphological changes on ice surfaces following progressive glacier shrinking. This positive feedback not only could delay glacier extinction in certain physiographic settings but also could introduce bias in paleo-glaciological reconstructions of climatic conditions.

The increase of current atmospheric CO2 and temperature can benefit leaf gas exchanges, carbohydrate content and growth in C4 grass invaders of the Cerrado biome

Leaf gas exchanges, carbohydrate metabolism and growth of three Brazilian Cerrado invasive African grasses were evaluated after growing for 75 days under doubled CO2 concentration and temperature elevated by 3 °C. Results showed that although the species presented photosynthetic C4 metabolism, they all had some kind of positive response to increased CO2. Urochloa brizantha and Megathyrsus maximus showed increased height for all induced environmental conditions. Urochloa decumbens showed only improvement in water use efficiency (WUE), while U. brizantha showed increased CO2 assimilation and M. maximus presented higher biomass accumulation under doubled CO2 concentration. The most significant improvement of increased CO2 in all three species appears to be the increase in WUE. This improvement probably explains the positive increase of photosynthesis and biomass accumulation presented by U. brizantha and M. maximus, respectively. The increase in temperature affected leaf carbohydrate content of M. maximus by reducing sucrose, glucose and fructose content. These reductions were not related to thermal stress since photosynthesis and growth were not harmed. Cellulose content was not affected in any of the three species, just the lignin content in U. decumbens and M. maximus. All treatments promoted lignin content reduction in U. brizantha, suggesting a delay in leaf maturation of this species. Together, the results indicate that climate change may differentially promote changes in leaf gas exchanges, carbohydrate content and growth in C4 plant species studied and all of them could benefit in some way from these changes, constituting a threat to the native Cerrado biodiversity.

Evaluation of the Foamability Potential of a Novel Biosurfactant Using the Solution to Advective-Diffusive Transport Model in Porous Media With a Linear Adsorption Trend

While geological sequestration of anthropogenic carbon dioxide is a technically and economically viable option for reducing emissions to the level required to avoid the predicted 2 degrees Celsius increase of atmospheric temperature by the end of this century, efficient sequestration planning is vital for the achievement of this goal.The petroleum industry has used conventional surfactants in enhance oil recovery projects aimed at prolonging the life span of a field, thereby increasing ultimate reserves. Notable among these is the use of surfactants for injected gas relative mobility control. Therefore, the potential for carbon dioxide mobility control in saline aquifers using surfactant alternating gas injection is huge, given the rich experience that can be tapped from the petroleum industry practice.Considering the expected surfactant loses in surfactant-enhanced geological sequestration similar to that encountered in the petroleum industry, this paper has used the analytical solution to advective diffusive equation that exists in the literature with a linear adsorption model where, adsorption has been used to predict trends in minimum pressure drop required for foam generation. The greatest utility of this work lies in the fact that the analytical solution is related a linear adsorption model related to a novel surfactant found from biological and hydrocarbon sources of geologic origin. This paper, therefore, extends the work of linear adsorption models for this novel surfactant aimed at exploring improved oil recovery potentials; in addition to exploring its potential for efficient geological carbon storage in saline aquifers.

The conservation of coral reefs through mangrove management

ABSTRACTCoral reefs in Malaysia face the critical threat of bleaching due to a considerable increase of both atmospheric temperatures and sea temperatures. Acidification of oceans, due to the increase of carbon absorbed by the sea, also contributes to the bleaching of coral reefs. Mangroves are known as ‘blue carbon sinks’ due to their ability to transfer and store carbon in their sediments and within plant parts at rates far greater than terrestrial forests. However, the destruction of mangroves has released the carbon stored within them, which has in turn contributed to the increase of atmospheric temperature. Under Malaysia’s National Forestry Act, logging of mangroves is permitted with licences granted by the Ministry of Forestry. Therefore, we attempt to investigate and propose a new legislation, the Mangroves Act and amend the existing National Forestry Act to remedy this current phenomenon. Qualitative methodology with analytical, historical and comparative approaches were adopted in this study and the results indicate that mangroves have great potential to conserve and protect coral reefs due to their role of controlling the increase of atmospheric temperature by storing carbon for decades.

Simulating the impact of climate change (elevated CO2 and temperature, and water deficit) on the growth of red and white Tempranillo grapevine in three consecutive growing seasons (2013–2015)

In recent decades, agricultural production is being affected by a sharp increase in atmospheric CO2 concentration. Due to the greenhouse effect gases, crops are impacted by enhanced temperatures and concomitantly by increased scarce water availability. All arid and semiarid areas, including Mediterranean viticulture, must face these three climate change-related factors: atmospheric CO2 concentration and temperature increases, and scarce water for irrigation. Scarce water is a problem even in irrigated viticulture, as irrigation is becoming more and more restricted. Within this context, the aim of this work was to investigate grapevine (Vitis vinifera L. cv. red and white Tempranillo) vegetative and reproductive growth. Fruit-bearing cuttings were grown under elevated CO2 (around 700 μmol mol−1 or ppm, versus 400), high temperature (ambient temperature + 4 °C, versus ambient) and water deficit (cyclic drought, versus full irrigated) in temperature gradient greenhouses for three consecutive growing seasons (years 2013, 2014 and 2015). Climate change impacted markedly vegetative growth. Within the abovementioned factors, vegetative growth (total vegetative mass) was significantly reduced by drought (consistent the three years) and was associated to a low substrate water status and low leaf stomatal conductance. Elevated CO2 stimulated total vegetative mass, whereas leaf area was not affected. When plants were grown under elevated CO2, the largest increases were observed in leaf (white) and root (red) growth. In these experiments, elevated CO2 did not compensate the negative effects of water stress. An increase of the mean temperature 4 °C had no consequences on vegetative growth. Yield and yield-related traits were unaffected by the climate change scenario.