Introductory remarks

The role played by electron density fluctuations near the plasma edge on rf current drive in tokamaks is assessed quantitatively. For this purpose, a general framework for incorporating density fluctuations in existing modelling tools has been developed. It is valid when rf power absorption takes place far from the fluctuating region of the plasma. The ray-tracing formalism is modified in order to take into account time-dependent perturbations of the density, while the Fokker–Planck solver remains unchanged. The evolution of the electron distribution function in time and space under the competing effects of collisions and quasilinear diffusion by rf waves is determined consistently with the time scale of fluctuations described as a statistical process.Using the ray-tracing code C3PO and the 3D linearized relativistic bounce-averaged Fokker–Planck solver LUKE, the effect of electron density fluctuations on the current driven by the lower hybrid (LH) and the electron cyclotron (EC) waves is estimated quantitatively. A thin fluctuating layer characterized by electron drift wave turbulence at the plasma edge is considered. The effect of fluctuations on the LH wave propagation is equivalent to a random scattering process with a broadening of the poloidal mode spectrum proportional to the level of the perturbation. However, in the multipass regime, the LH current density profile remains sensitive to the ray chaotic behaviour, which is not averaged by fluctuations. The effect of large amplitude fluctuations on the EC driven current is found to be similar to an anomalous radial transport of the fast electrons. The resulting lower current drive efficiency and broader current profile are in better agreement with experimental observations. Finally, applied to the ITER ELMy H-mode regime, the model predicts a significant broadening of the EC driven current density profile with the fluctuation level, which can make the stabilization of neoclassical tearing mode potentially more challenging.

Formulation of the problem. This is the second part of a trilogy dedicated to the analysis of climate indicators in central Ukraine over the entire period of instrumental observations, which analyzes air temperature data from the weather stations of Uman, Kropyvnytskyi, and Poltava. This work addresses issues related to the 13th Sustainable Development Goal, which is to combat climate change and strengthen resilience and adaptation to climate-related hazards and disasters in all countries. The purpose of this study was to analyze data from weather stations in central Ukraine that have the longest period of observation and to find patterns in the dynamics of temperature indicators over the past 140-200 years. Data and methods. To characterize the climate of central Ukraine, we analyzed the average monthly and average annual temperatures of Uman, Kropyvnytskyi, and Poltava, which have the longest continuous or almost continuous period of observation. Based on these data, we have constructed graphs of changes in the average annual and average monthly temperatures for the winter and spring seasons. To analyze the dynamics of temperature indicators, we constructed linear and 11-year moving trends. Results. At all weather stations, there is a trend towards an increase in both average annual air temperatures and temperatures for certain months. In particular, in Uman, the average annual temperature over the entire observation period (138 years) has increased from +6.80C to +8.60C, i.e. by 1.8 degrees. In Kropyvnytskyi, average annual temperatures over 149 years increased from +7.40C to +8.90C, i.e. by 1.5 degrees. In Poltava, the average annual temperature over 199 years has increased from +5.90C to +8.70C, i.e. by 2.8 degrees (since 1886 from +6.40C to +8.70C, i.e. by 2.3 degrees). At all weather stations, the most significant increase in average annual temperatures occurred between 1989 and 2023. Temperatures in the autumn months increased the least. Over the entire observation period, average monthly temperatures in September/October/November increased from 0.3/0.1/0.10C in Uman, 0.6/0.1/1.80C in Kropyvnytskyi to 1.5/1.2/1.90C (since 1886 – 0.9/0.9/1.70C) in Poltava. All three meteorological stations have common periods of temperature increases and decreases, in particular, a decrease in average monthly summer temperatures occurred from 1947-1969 to 1985-1995; from 1986-1996 to 2023, an increase in air temperature. Air temperatures in the summer months have increased quite significantly. Over the entire period of observation, the average monthly temperature in June/July/August increased from 0.9/0.3/0.70C in Kropyvnytskyi, 1.9/1.3/1.60C (since 1886 – 1.3/1.2/1.40C) in Poltava to 2.0/1.1/1.10C in Uman. The greatest increase in average monthly autumn temperatures occurred from 1999-2001 to 2023. Analyzing the graphs of 11-year moving averages, one can see the presence of periods of increase and decrease in average monthly temperatures lasting about 33 years or doubled periods lasting about 66 years. Scientific novelty. For the first time, the data of meteorological stations in central Ukraine for the entire period of observation (138 years – Uman, 149 years – Kropyvnytskyi, 199 years – Poltava) were analyzed and regularities in the dynamics of temperature indicators were determined. The practical significance lies in the possibility of using the results of the study to predict future climate change.

The potential effects of climate change on the hydrology and water resources of the Colorado River basin are assessed by comparing simulated hydrologic and water resources scenarios derived from downscaled climate simulations of the U.S. Department of Energy/National Center for Atmospheric Research Parallel Climate Model (PCM) to scenarios driven by observed historical (1950–1999) climate. PCM climate scenarios include an ensemble of three 105-year future climate simulations based on projected `business-as-usual'(BAU) greenhouse gas emissions and a control climate simulation based on static 1995 greenhouse gas concentrations. Downscaled transient temperature and precipitation sequences were extracted from PCM simulations, and were used to drive the Variable Infiltration Capacity (VIC) macroscale hydrology model to produce corresponding streamflow sequences. Results for the BAU scenarios were summarized into Periods 1, 2, and 3 (2010–2039,2040–2069, 2070–2098). Average annual temperature changes for the Colorado Riverbasin were 0.5 °C warmer for control climate, and 1.0, 1.7, and 2.4 °C warmer for Periods 1–3, respectively, relative to the historicalclimate. Basin-average annual precipitation for the control climate was slightly(1%) less than for observed historical climate, and 3, 6, and 3%less for future Periods 1–3, respectively. Annual runoff in the controlrun was about 10% lower than for simulated historical conditions, and 14, 18, and 17% less for Periods 1–3, respectively. Analysis of watermanagement operations using a water management model driven by simulated streamflows showed that streamflows associated with control and future BAU climates would significantly degrade the performance of the water resourcessystem relative to historical conditions, with average total basin storage reduced by 7% for the control climate and 36, 32 and 40% for Periods 1–3, respectively. Releases from Glen Canyon Dam to the LowerBasin (mandated by the Colorado River Compact) were met in 80% of years for the control climate simulation (versus 92% in the historical climate simulation), and only in 59–75% of years for the future climate runs. Annual hydropower output was also significantly reduced for the control and future climate simulations. The high sensitivity of reservoir system performance for future climate is a reflection of the fragile equilibrium that now exists in operation of the system, with system demands only slightly less than long-term mean annual inflow.

Maxwell-Wien bridge with vector voltmeter system for measurement small and rapid changes in inductive-loop sensor impedance components

در این پژوهش برونداد سه مدل از مدل‌های فاز ششمCMIP6 (Coupled Model Intercomparison Project phase 6) برای درستی‌سنجی انتخاب و چشم‌انداز بلندمدت دمای آیندة کشور پیش‌نگری شد. بنابراین از دو دسته داده شامل دمای 43 ایستگاه­ همدید و برونداد سه مدل BCC-CSM2-MR، CAMS-CSM1-0 و MRI-ESM2-0 از مجموعه مدل­های CMIP6 برای دو دوره (2009-۱۹۹۰ و 2100-2020) با تفکیک افقی ۱۰۰ کیلومتر و سنجه­های متداول آماری شامل MAE (Mean Absolute Error)، MBE (Mean Bias Error)، RMSE(Root Mean Square Error)، t-Jacovids برای اختلاف دمای ایستگاه و مدل­ها استفاده شد. مقایسة سنجه­های آماری محاسبه‌شده نشان‌دهندة عملکرد بهتر مدل MRI-ESM2-0 در بین سه مدل یاد‌شده می‌باشد. بنابراین مدل MRI-ESM2-0 به‌عنوان مدل منتخب جهت پیش‌نگری دمای آتی کشور تحت دو سناریوی SSP2-4.5 و SSP5-8.5 انتخاب شد. برای حذف اریبی مدلMRI-ESM2-0 از روش تغییر عامل دلتا DCF (Delta Change Factor) و برای مطالعة روند و شیب روند از آزمون‌های من-کندال و سنس استفاده شد. به‌طورکلی نتایج بیانگر بی­هنجاری مثبت دما (متوسط سالانة کل کشور برای سناریو SSP2-4.5، 15/2 و SSP5-8.5، 34/3 oC) در ایران در تمام ماه­های سال تا پایان قرن بیست‌ویکم است. شدت بی­هنجاری در ماه‌های گرم سال بیشتر از ماه­های سرد سال است. متوسط روند دما در تمامی ماه­ها و سناریوها افزایشی و این مقدار از نظر آماری در سطح 1/0 معنی­دار است. متوسط شیب روند بین سالانه در سناریوی SSP2-4.5، year-1 02/0 و بر اساس سناریوی SSP5-8.5، year-1 05/0 درجة سلسیوس محاسبه شد. پیش‌نگری دما در چشم‌انداز بلندمدت نشان داد بیشینة بی­هنجاری دمای ایران در مناطق مرتفع و کمینة بی­هنجاری در سواحل شمالی، شمال­شرق و سواحلی جنوبی خواهد بود.

Abstract. The aim of our study was to use the coupled climate-carbon cycle model HadCM3C to quantify climate impact of ecosystem changes over recent decades and under future scenarios, due to changes in both atmospheric CO2 and surface albedo. We use two future scenarios – the IPCC SRES A1B scenario, and a climate stabilisation scenario (2C20), allowing us to assess the impact of climate mitigation on results. We performed a pair of simulations under each scenario – one in which vegetation was fixed at the initial state and one in which vegetation changes dynamically in response to climate change, as determined by the interactive vegetation model within HadCM3C. In our simulations with interactive vegetation, relatively small changes in global vegetation coverage were found, mainly dominated by increases in shrub and needleleaf trees at high latitudes and losses of broadleaf trees and grasses across the Amazon. Globally this led to a loss of terrestrial carbon, mainly from the soil. Global changes in carbon storage were related to the regional losses from the Amazon and gains at high latitude. Regional differences in carbon storage between the two scenarios were largely driven by the balance between warming-enhanced decomposition and altered vegetation growth. Globally, interactive vegetation reduced albedo acting to enhance albedo changes due to climate change. This was mainly related to the darker land surface over high latitudes (due to vegetation expansion, particularly during December–January and March–May); small increases in albedo occurred over the Amazon. As a result, there was a relatively small impact of vegetation change on most global annual mean climate variables, which was generally greater under A1B than 2C20, with markedly stronger local-to-regional and seasonal impacts. Globally, vegetation change amplified future annual temperature increases by 0.24 and 0.15 K (under A1B and 2C20, respectively) and increased global precipitation, with reductions in precipitation over the Amazon and increases over high latitudes. In general, changes were stronger over land – for example, global temperature changes due to interactive vegetation of 0.43 and 0.28 K under A1B and 2C20, respectively. Regionally, the warming influence of future vegetation change in our simulations was driven by the balance between driving factors. For instance, reduced tree cover over the Amazon reduced evaporation (particularly during June–August), outweighing the cooling influence of any small albedo changes. In contrast, at high latitudes the warming impact of reduced albedo (particularly during December–February and March–May) due to increased vegetation cover appears to have offset any cooling due to small evaporation increases. Climate mitigation generally reduced the impact of vegetation change on future global and regional climate in our simulations. Our study therefore suggests that there is a need to consider both biogeochemical and biophysical effects in climate adaptation and mitigation decision making.

Hygrothermal resilience of typical lightweight steel-framed wall assemblies in hot-humid areas under future climate uncertainty

The <scp>United Nations</scp> Sustainable Development Goals: Aspirational or obtainable?

This article discusses issues concerning international legal regulation of coopera-tion of states in resolving the problems related to ensuring the human rights to ad-equate food and food security in general, including in the context of a pandemic that has had a significant impact on the development of the world's economy. The work studies: the development of international legal regulation of partnership in the field of food security, the goals and authority of Food and Agriculture Organi-zation (FAO), the conditions of the food market and the world's economy. The study examines the right of everyone to access safe and healthy food, in accord-ance with the right to for adequate food and the basic right of everyone to be free from hunger. It is noted that the world food security system covers: the creation of national food supplies coordinated on the international level; provision of food aid to countries in need, organization of an early warning system on food shortage; an increase of the share of developing countries in international trade of agriculture products. One of the factors of the establishment of intranational food security is food sup-port to developing states. The article considers various principles like roman princi-ples of sustainable global food security; a comprehensive approach to food securi-ty; strategic coordinative cooperation; the principle of supporting national, region-al and international programs; close interaction with international organizations and principle of maintaining of assumed financial obligations. It is noted that the lack of positive results in a process of resolving issues concern-ing food supply requires improvement of the effectiveness of multilateral man-agement system dealing with ensuring world's food security, through the unifica-tion and coordination of efforts of states, international organizations, and other interested parties at local and global levels. A similar policy is proposed to be considered in complex with global and regional issues, including negotiations on the creation of a fair international trade regime, which will positively affect the strengthening of national food security potential of developing countries and improve the effectiveness of international food assis-tance programs. Such policy is proposed to be reflected and specified in agriculture doctrines of national and regional levels.

Introduction: Aesthetic materials for direct restorations can suffer changes in the oral cavity due to multiple factors acting at this level. The aim of the study was to demonstrate that aesthetic materials undergo structural changes in texture and chemicals, depending on the nature of the extrinsic factor, concentration, and exposure time. Material and methods: We used 3 types of composites, a self-polymerizing composite, two photo-polymerizing composites, and a glass ionomer. 210 teeth were initially immersed in artificial saliva as a control solution and afterwards immersed into artificial gastric juice, ethyl alcohol, energy drink, and distilled water. With the help of a pH meter, we determined the pH of the substances both before and after immersing the teeth in solutions. The teeth were monitored for 24-48 hours in a thermostat bath at 37 degrees Celsius, after which they were analyzed with the help of a rough meter that measures the smallest surface changes. Results: Significant changes in pH occurred in alcohol, where a considerable decrease was observed after 48h. Also, the alcohol produced the most aggressive changes of texture in the composites, and the smallest changes occured in the composite with nanofiller. The glass ionomer was the most affected of all the materials due to the exposure to both alcohol and artificial gastric juice, respectively energy drinks so that the surface analysis could not be performed. Conclusions: The results of the in vitro study are clinically important because the glass ionomer is much too rotten in these extreme situations. Thus, its use is not recommended both in patients with gastroesophageal reflux as well as in alcoholics and persons consuming energy drinks.

Although acclaimed as a biofuel crop with high potential to sustainably replace fossil fuels, Jatropha curcas L. remains a poorly studied plant. Reliable yield assessments with conventional methods require agroclimatic and physiological knowledge, which is not yet available for Jatropha. To fill this gap, we tested a novel two‐step approach integrating knowledge from biogeography and population biology with available Jatropha field data. In the first step, using MaxEnt, a widely implemented model in biogeography, we predicted Jatropha fitness in response to climate by relating natural occurrence recorded in herbaria with bioclimatic geodatasets. In the second step, we relied on population biology principles supported by seed mass addition experiments to relate fitness to reproductive potential, hence seed yield. Jatropha seed yield in response to climate was mapped worldwide for actual (1950–2000 average) and future (2020) climate conditions. The modelled Jatropha seed yield was validated against a set of on‐field yield assessments (R2=0.67, P&lt;0.001). The discrepancies between estimated and measured yields were partially explained by model uncertainties, as quantified by the sensitivity analysis of our modelling (R2=0.57, P=0.001). Jatropha has a pan‐tropical distribution, plus specific adaptability to hot temperate areas. Climate variables most significantly affecting modelled yield response were annual average temperature, minimum temperature, annual precipitation and precipitation seasonality.

Opportunities and challenges in assessing climate change vulnerability through genomics

A scholarly life-history model, applicable to various ontogenies, requires precise definitions of the major periods and their boundaries. The theory of saltatory ontogeny enables one to construct such a model based on natural boundaries between consecutive intervals of development. This theory stipulates that development does not proceed by a continuous accumulation of inconspicuous, small changes but is a sequence of rapid changes in form and function alternating with prolonged intervals (steady states) of slower development during which complex structures are prepared for the next rapid change. These times of rapid changes from one steady state to the next are called thresholds and represent decisive events of life history. Saltation explains some of the most misunderstood events of ontogeny. For example, it explains why only activation should be accepted as the beginning of ontogeny, and why insemination, fertilization, and hatching are not the appropriate clues for timing ontogeny. Similarly, it is argued that according to the definition of the larva period–lasting from onset of exogenous feeding until metamorphosis–not all fishes have larvae. In fishes with an increased endogenous food supply and parental care (increased reproductive cost per embryo), the embryo develops permanent organs directly, bypassing the larva period with its remodelling of temporary structures. Hatching is rarely a developmental threshold. The transition to exogenous feeding, rather than hatching, is the decisive threshold of ultimate survival value.

ABSTRACTWhen climate shifts abruptly, changes occur so rapidly and unexpectedly that human and natural systems have difficulty adapting to, or coping with, them. By using palaeoclimatic indicators such as tree and coral growth rings, ice cores and deep sea sediments, climate scientists have uncovered many instances of abrupt and relatively shortlived climate changes in the past. These abrupt changes (some taking place within several - 50 years) are especially evident over the last 100,000 years when the planet, under longer-term Milankovitch and other forcings, was slipping into and then out of an ice age. Relatively short-term thermohaline (temperature and salt) driven changes in the vigour and distribution of ocean currents are believed to lie at the heart of the abrupt climate shifts. In particular, thermohaline driven changes between three ‘modes’ of the North Atlantic Conveyor (incorporating the Gulf Stream and North Atlantic Drift) are held to be the key factor explaining abrupt climate shifts over the North Atlantic and adjacent regions. By switching from an ‘on’ mode (maximum heat advection) to a ‘half-on’ mode (moderate heat advection) to an ‘off’ mode (little heat advection) and back again, the Northern Conveyor is thought to drive the main pattern in abrupt climate change in the North Atlantic region during the last ice age. This pattern involves multiple sequences of rapid switching from relatively warm periods (interstadials), to cold periods (Dansgaard-Oeschger events) to very cold episodes (Heinrich events) and then back to warm interstadial periods.By currently releasing massive quantities of fresh water into the North Atlantic through ice melt, global warming today is seen as a powerful mechanism able to switch the present ‘on’ state of the Northern Conveyor to the ‘half- on’ and even the ‘off’ mode condition. Global warming paradoxically has the potential to plunge the northern Atlantic region into new glacial conditions. Because some scientists and others in the media believe in the return or near return of an ice age, this possibility is addressed in our article. Using modern high quality palaeoclimatic data (ice cores and deep sea sediments) a comparison of the last four interglacials, including MIS 11 (430,000years ago), shows us that natural factors alone are unlikely to cause a quick return to ice age conditions. In addition, theoretical and empirical findings together with modelling studies of the Northern Conveyor reveal that although there is likely to be a significant weakening in the Gulf Stream/North Atlantic Drift by the end of the present century, a total collapse of the system is not expected. In terms of our future climate, therefore, we should expect continued warming as a result of anthropogenic release of greenhouse gases rather than cooling over the next 50-80years. One favourite climate scenario suggests that cooling by a shut-down of the Gulf Stream at the end of the present century is more than likely to be balanced by global warming. In the final analysis, however, there are too many uncertainties in the science of climate change for us to be confident of what the climate will be like in the future. What we do know with a better level of authority is that abrupt climate change was a feature of the past, and it could well be one of the future.

Projecting population growth as a dynamic measure of regional urban warming