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Average monthly air temperatures in Bosnia and Herzegovina (BiH) exhibit a notable rise during summer, ranging from 0.4 to 0.8 °C per decade, while precipitation experiences a significant decrease of up to 8 mm per decade. Climate models, across various RCP scenarios, project an increase in air temperature, that is most pronounced in the summer season. Additionally, there is a projected frequency and intensity of heavy precipitation during autumn. In BiH, agricultural production faces substantial risks, including droughts, spring and autumn frosts, hail, and floods. Recent years have witnessed extreme hydrological events, notably the 2012 drought and the 2014 floods. Strategic documents highlight the critical importance of addressing floods and droughts for agriculture, as well as their implications for the environment, households, and industry. To assess the severity of extreme hydrological events and their impact on agriculture, with a specific emphasis on autumn and summer in Bosnia and Herzegovina, average and peak values of the Standardized precipitation evapotranspiration index (SPEI) were calculated separately for the periods 1961-1990 and 1991-2020, focusing on October and August. Compared to the reference climatic period the current climate is characterized by shifts between intense wet and dry periods, with very few years exhibiting stable and expected weather conditions. Identified as extremely wet and flood-prone years, SPEI2 October values for 1974 (2.42), 1996 (2.13), 2001 (2.24), and 2014 (2.05) stand out, with only one extremely dry year in 1985 (-2.21). SPEI2 August indicates extremely dry years, notably 2012 (-2.35) and 2017 (-2.25). [ABSTRACT FROM AUTHOR]

Global warming is causing an intensification of extreme climate events with significant changes in frequency, duration, and intensity over many regions. Understanding the current and future influence of this warming in northeastern Brazil (NEB) is important due to the region's greater vulnerability to natural disasters, as historical records show. In this paper, characteristics of climate change projections (precipitation and air temperature) over NEB are analyzed using 15 models of Coupled Model Intercomparison Project Phase 6 (CMIP6) under four Shared Socioeconomic Pathways (SSPs: SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5) scenarios. By using the Taylor diagram, we observed that the HadGEM3-GC31-MM model simulates the seasonal behavior of climate variables more efficiently. Projections for NEB indicate an irreversible increase in average air temperature of at least 1 °C throughout the 21st century, with a reduction of up to 30% in annual rainfall, as present in scenarios of regional rivalry (SSP3-7.0) and high emissions (SSP5-8.5). This means that a higher concentration of greenhouse gases (GHG) will increase air temperature, evaporation, and evapotranspiration, reducing rainfall and increasing drought events. The results obtained in this work are essential for the elaboration of effective strategies for adapting to and mitigating climate change for the NEB. [ABSTRACT FROM AUTHOR]

The reality of climate change is accepted by the vast majority of the scientific community (IPCC, 2014). Among human activities, agriculture - especially viticulture - is highly dependent on climatic conditions during the growing season. This paper aims to address a complex study on the evolution / trend of the main annual climate indicators and during the vegetation period (air temperature, precipitation, insolation, air hygroscopicity) and climate indicators with synthetic character (Ihr, CH, Ibcv, IAOe) in the viticultural area of Odobeşti vineyard. The climatic data analyzed in this study were recorded at the weather station of R.S.V.O. Odobeşti, in the period 1946-2020, during 75 years. The analysis of the recorded data highlighted clear trends in the evolution of climatic factors in the Odobeşti wine ecosystem, which certifies the reality of phenomena specific to climate change, with a direct impact on the vegetative and productive potential of vineyards. There is an increase in the annual and average values of the analyzed climatic indicators and an increasing frequency of extreme climatic phenomena. [ABSTRACT FROM AUTHOR]

The influences of human activity on regional climate over China have been widely reported and drawn great attention from both the scientific community and governments. This paper reviews the evidence of the anthropogenic influence on regional climate over China from the perspectives of surface air temperature (SAT), precipitation, droughts, and surface wind speed, based on studies published since 2018. The reviewed evidence indicates that human activities, including greenhouse gas and anthropogenic aerosol emissions, land use and cover change, urbanization, and anthropogenic heat release, have contributed to changes in the SAT trend and the likelihood of regional record-breaking extreme high/low temperature events over China. The anthropogenically forced SAT signal can be detected back to the 1870s in the southeastern Tibetan Plateau region. Although the anthropogenic signal of summer precipitation over China is detectable and anthropogenic forcing has contributed to an increased likelihood of regional record-breaking heavy/low precipitation events, the anthropogenic precipitation signal over China is relatively obscure. Moreover, human activities have also contributed to a decline in surface wind speed, weakening of monsoon precipitation, and an increase in the frequency of droughts and compound extreme climate/weather events over China in recent decades. This review can serve as a reference both for further understanding the causes of regional climate changes over China and for sound decision-making on regional climate mitigation and adaptation. Additionally, a few key or challenging scientific issues associated with the human influence on regional climate changes are discussed in the context of future research. [ABSTRACT FROM AUTHOR]

Despite efforts to mitigate climate change, annual greenhouse gas emissions continue to rise, which may lead to the global warming of our planet. Buildings' thermal energy needs are inherently linked to climate conditions. Consequently, it is crucial to evaluate how climate change affects these energy demands. Despite extensive analysis, a comprehensive assessment involving a diverse range of building types has not been consistently conducted. The primary objective of this research is to perform a coherent evaluation of the influence of climate changes, construction element properties, and the Heating, Ventilation, and Air Conditioning (HVAC) system type of control on the energy requirements of six buildings (residential, services, and commercial). The buildings are considered to be located in a temperate Mediterranean climate. Our focus is on the year 2070, considering three distinct climatic scenarios: (i) maintaining the current climate without further changes, (ii) moderate climate changes, and (iii) extreme climate changes. The buildings are distributed across three different locations, each characterized by unique climatic conditions. Buildings' envelope features a traditional External Thermal Insulation Composite System (ETICS) and expanded polystyrene (EPS) serves as thermal insulation material. Two critical design factors are explored: EPS thickness ranging from 0 (no insulation) to 12 cm; and horizontal external fixed shading elements varying lengths from 0 (absence) to 150 cm. Six alternative setpoint ranges are assessed for the HVAC system control: three based on the Predicted Mean Vote (PMV) and three based on indoor air temperature (Tair). Results were obtained with a validated in-home software tool. They show that, even under extreme climate conditions, the application of thermal insulation remains energetically favorable; however, its relative importance diminishes as climate severity increases. Then, proper insulation design remains important for energy efficiency. The use of external shading elements for glazing (e.g., overhangs, louvers) proves beneficial in specific cases. As climate changes intensify, the significance of shading elements grows. Thus, strategic placement and design are necessary for good results. The HVAC system's energy consumption depends on the level of thermal comfort requirements, on the climate characteristics, and on the building's type of use. As climate change severity intensifies, energy demands for cooling increase, whereas energy needs for heating decrease. However, it is essential to recognize that the impact of climate changes on HVAC system energy consumption significantly depends on the type of building. [ABSTRACT FROM AUTHOR]

The air temperature in Bosnia and Herzegovina is increasing (0.3 - 0.6 °C per decade), while rainfall events are more extreme. Additionally, there is an increased variability in weather conditions across all seasons, marked by rapid shifts from extremely cold to warm weather, as well as transitions from periods of exceptionally high rainfall to exceedingly dry periods. Droughts and floods pose the most significant risks. However, Bosnia and Herzegovina faces a lack of adequate information and analyses of extreme climate events, especially regarding their timing, intensity, magnitude, duration, and spatial extent. Therefore, this study aims to address these questions using the precise drought index SPEI. The identified wet years were: 1969, 1970, 1976, 1978, 1999, 2001, 2010, 2013, and 2014, while the dry years were 1961, 1971, 1983, 1990, 2000, 2003, 2007, 2011, 2012, and 2020. In the northern and western regions of BiH, the longest wet period in terms of duration and spatial extent occurred from May 2014 to July 2015. In the central and southern parts of BiH, the longest wet period extended over 19 months from February 1969 to August 1970. The longest drought with the largest spatial extent was the drought from August 2011 to July 2013. The obtained data shows a significant shift towards drier weather, as dry months have increased by 15% compared to wet months. At the same time, there has been a decrease in near-normal conditions and an increase in extremely wet months. [ABSTRACT FROM AUTHOR]

The increased frequency of climate extremes associated with ongoing climate change has the potential for significant impacts on maize grain yield in maize-producing regions worldwide. In this study, we used a modeling approach to investigate the effects of different types of climatic extremes on maize grain yield in Northeast China. We combined annual mean air temperature and accumulated precipitation data and divided the climate years into 9 categories, using the 10th and 90th percentiles as extreme thresholds. The climate data were represented by 1 normal climate type, 4 individual climate extremes, and 4 combined climate extremes. Changes in the frequencies of climate extremes and their impacts on maize grain yields were analyzed for two 30-year periods (period I: 1960–1989; period II: 1990–2019) using the Agricultural Production Systems sIMulator (APSIM-Maize). Compared with period I, the occurrences of the normal climate and all 3 cold-related climate extremes (i.e., cold-normal, cold-humid, and cold-dry) decreased during period II, while occurrences of the other climate extremes increased. Moreover, according to the APSIM-Maize model, the estimated yield in the years with a normal climate decreased by 4.01%; the 3 cold-related climate extremes increased yields by 26.56%, 12.10%, and 6.68%, respectively; the 2 warm-related climate extremes (warm-normal and warm-dry) and normal-humid years decreased estimated yields by 6.39%, 24.12%, and 5.10%, respectively. The increase in the occurrence of warm-humid years increased the estimated yield by 11.69%. This work confirms the adverse effects of warmer temperatures in the absence of excess rainfall on grain yield and highlights the importance of extremely dry or wet conditions under normal temperature conditions. [ABSTRACT FROM AUTHOR]

High‐latitude Asia (above 60°N) is highly sensitive to global climate change. Warming has led to frequent extreme climate events and has produced important impacts on both the ecological environment and social economy. However, station observations are scarce and there is limited climate change research in the region. Reanalysis data is a potential alternative to scarce observations, but its suitability in high‐latitude Asia has not been well evaluated. In this study, we systematically evaluate the abilities of five reanalysis datasets (MERRA‐2, CFSR, ERA‐Interim, JRA‐55, and ERA5) and one gridded observation dataset (CPC) to characterize mean/extreme temperature and precipitation in high‐latitude Asia through comparison with GHCN‐D station observations. All six datasets reasonably reproduce spatial and temporal variations in mean/extreme temperature and precipitation over the region and match well with the observed climatology. Of these datasets, CPC shows the best performance for mean/extreme temperature and precipitation in high‐latitude Asia, because it is produced through interpolation of station observations. Among the five reanalysis datasets, ERA5 overall shows the best agreement with observed spatiotemporal changes in mean/extreme temperature and precipitation, although it is not superior for all variables. Temperature is generally characterized better than precipitation in these datasets. These results will be helpful for the selection and improvement of reanalyses and thus further climate research in high‐latitude Asia. [ABSTRACT FROM AUTHOR]

Forest ecosystems in Europe undergo cyclic fluctuations with alternating periods of forest prosperity and disturbances. Forest disturbances are caused by large-scale calamities (climate-induced and unforeseen events) resulting in an increased volume of salvage logging. In recent decades, climate change (warming, long-term droughts, more frequent storms, bark beetle outbreaks) has contributed to an increased frequency of salvage logging. However, until now, it has not been revealed what triggers national-scale forest calamities. All of the above-mentioned natural disturbances are connected to solar activity, which is the driver of climate change. This research relates the total volume of harvested timber and salvage logging to the climate and cosmic factors in the Czech Republic, Central Europe. Data of total and salvage logging are compared with air temperatures, precipitation, extreme climatic events, sunspot areas, and cosmic ray intensities. The results document a significant effect of average annual temperatures on the total and salvage logging for the entire period of observations since 1961. A significant correlation of salvage logging to the sunspot area and cosmic ray intensity was observed. The link between salvage logging and sunspots and cosmic ray intensity is supported by spectral analysis in which a significant 11-year cycle was observed since 1973. The results also show an increasing significant effect of sunspots and cosmic ray intensity on logging in recent years in connection with synergism of extreme climate events and the subsequent bark beetle outbreaks. Space and cosmic effects are factors that substantially influence forest ecosystems. Therefore, this paper provides new knowledge about, and possible predictions of, the forest response under climate change. [ABSTRACT FROM AUTHOR]

ABSTRACT Non-stationary modelling of climate extremes has attracted significant attention in recent years. Generalized extreme value ( GEV) distribution is the standard approach for modelling block extremes. The non-stationary form of GEV distribution with location and scale parameters linearly regressing to time has been widely used for single-site time series of climate extremes. In the present paper, such a model is extended to be geoadditive for regional climate extremes with nonparametric spatially varying temporal effects. The model is implemented through the Bayesian hierarchical approach and is applied to the annual minimum surface air temperature in Mainland China as a demonstration. The five bivariate functions representing the regional regression parameters in the model are approximated by low-rank thin plate regression splines. All the necessary software tools for producing a thin plate regression spline basis and Markov Chain Monte Carlo sampling can be seamlessly integrated and called through the R software environment. Results show that the model can capture the spatial inhomogeneity and temporal non-stationarity features of regional climate extremes. Expressions for return levels with different return periods and their trends are also derived accordingly. Trends in different return levels, especially those in the 'extreme state' (e.g., 50-year return level) that cannot be inferred by usual observational trend analysis, can also be derived through samples drawn from posterior predictive distributions. The regional trend in a 50-year return level is quite different to that in a 2-year return level. More attention should be paid to trends in the extreme state of climate under climate change. [ABSTRACT FROM AUTHOR]

Climate is a key factor in agriculture, but we are unable to adequately predict future climates. Although some studies have addressed the short and long-run impacts of climate change on agriculture, few of them specifically focused on the analysis of its thermal component. Climatic regions with an extreme thermal range are a special case, as seasonal contrasts complicate the picture. Based on the above, the purpose of the paper is twofold. First, we review methods and indices used for the estimation of changes in the thermal component of the climate and demonstrate the usefulness of a sensitivity assessment methodology that gives some indication of the likely spatial extent of areas of high or low sensitivity to climate change and the size of the potential impact of that change, which is specifically beneficial in regions with high temperature extremes. Secondly, we constructed a composite indicator, called the Growing Degree Day Sensitivity Index (GDDSI) and defined as the percentage change in Growing Degree Day (GDD) for warming scenarios +1, +2 and +3 °C. GDDs were calculated for threshold base air temperatures of 0, 5, 10 and 15 °C, and a high-temperature limit of 30 °C. A GDD sensitivity analysis was applied to the thermally extreme climate of the Russian Far East. We analyzed the data of 50 weather stations across the study region over the period 1966–2017. The results show a strong GDDSI north-to-south gradient. In most cases, the sensitivity does not increase significantly as the warming rate increases. The higher the base threshold, the higher the sensitivity: GDDs with a threshold at 15 °C had the highest sensitivity in the far north of the study area where conditions are currently marginal for crop growth. The sensitivity analysis circumnavigates the difficulty of uncertainty in knowing what future climate to expect and informs planning decisions. The mapped results are useful for identifying areas of high sensitivity to climate change as well as the magnitude of the potential impact of that change. [ABSTRACT FROM AUTHOR]

Identifying general circulation models (GCMs) that represent the climate of a specific area is crucial for climate change studies. However, the uncertainties in GCMs caused by computational constraints, such as coarser resolution, physical parameterizations, initializations, and model structures, make it imperative to identify a representative individual or group of GCM for a climate impact study. An advanced envelope-based multi-criteria selection approach was used to identify a subset of the most appropriate future GCMs in the Upper Awash Basin (UAB). The skill accounting is based on (1) the range of projected mean changes of climate variables, (2) range of variability in climate extremes, and (3) model run performance to represent historical climate data. Statistical Downscaling and bias correction were made for the selected model runs. The downscaled and bias-corrected monthly values for precipitation are expected to increase from 0.42 to 2.82% in mid-century and 0.15 to 3.79% by the end century, considering the SSP4.5 scenario. For SSP8.5, it increases from 1.45 to 5.51% and 2.57 to 9.78% in the respective periods. Likewise, under the SSP4.5 forcing scenario, the monthly average air temperature projected to be warmer, which increased from 0.68 to 1.5 °C during mid-century and 0.09 to 1.92 °C end-of-century. Meanwhile, for SSP8.5, the projection indicates an increment of 0.19 to 1.98 °C under mid-century and 2.37 to 7.00 °C end-century. The projected change of future precipitation and temperature in the study basin increases the precipitation intensities, wet days and dry spells due to high-temperature increment. [ABSTRACT FROM AUTHOR]

The signal of temperature change has emerged from background variations in most tropical regions in boreal summer over decadal‐centennial timescales but not in northern‐central India (NCI). In this study, we investigated the reason for the limited temperature change in NCI. We found that internal variability, largely caused by the Interdecadal Pacific Oscillation (IPO) on a ∼20‐year timescale, has the potential to mask the temperature change signal. Besides, local response to external forcing, linked to non‐greenhouse gas (GHG) forcings, strongly overrides GHG warming in NCI, which results in little trend in the temporal evolution of external variability. The internal variability related to IPO and the limited warming arising from the competition between multiple forcings result in the smallest signal‐to‐noise ratio and thus, the temperature change signal fails to emerge from the background variations. Plain Language Summary: Earth's surface has warmed considerably since 1850s, which can be largely attributed to anthropogenic greenhouse gas emissions. When human activities (e.g., greenhouse gas emissions) cause the local temperature change to exceed the inherent variation of the climate system, the region will face more extreme climate events. Although temperature has experienced warming almost all around the globe, here we show that surface air temperature in boreal summer in northern‐central India has not gone through significant changes. The timing of transition is important for policymakers. Thus, we analyzed the reasons for this and show that it reflects the combined effects of natural processes and local anthropogenic forcings. Key Points: The external forcing exhibits a cooling trend in northern‐central India (NCI), whereas most global regions have warmed considerablyCooling effects of non‐greenhouse gas forcings that override global warming lead to a cooling trend in NCIThe internal variability related to the Interdecadal Pacific Oscillation and the limited warming cause the smallest signal‐to‐noise ratio [ABSTRACT FROM AUTHOR]

Ongoing climate change most pronounces itself in northern latitudes, including in the Arctic zone of the Russian Federation (AZRF). Climate change is a complex multidirectional process that is characterized by both positive and negative effects on the functioning of territorial economic systems. In this regard, an analysis of the impacts of climate change on economic development is a particularly urgent scientific and practical task that requires comprehensive study. This research was devoted to assessing the probable impacts of climate transformations on the parameters of the economic development of the AZRF regions. The authors created a methodological approach to the assessment of the costs of the effects of climate change for the economy of the AZRF regions, taking into account the average predicted dynamics of surface air temperature and key regional economic specializations, as well as the degree of susceptibility of various industries to the climate change. The energy industry was considered in particular detail since it is the basis for all of the other industries and is the guarantor of life support for the populations that live in the extreme Arctic climate. Calculations have shown that the accumulated economic effects of climate change as a whole for the AZRF economy during the period 2020–2050 will be negative and have been estimated as having a cost of more than RUB 8 trillion (or nearly USD 111 billion in 2020 prices), which would be about 3% of total Russian Arctic GRP in average annual terms. [ABSTRACT FROM AUTHOR]

China's climate has been warming since the 1950s, with surface air temperature increasing at a rate higher than the global average. Changes in climate have exerted substantial impacts on water resources, agriculture, ecosystems and human health. Attributing past changes to causes provides a scientific foundation for national and international climate policies. Here, we review recent progress in attributing the observed climate changes over past decades in China. Anthropogenic forcings, dominated by greenhouse gas emissions, are the main drivers for observed increases in mean and extreme temperatures. Evidence of the effect of anthropogenic forcings on precipitation is emerging. Human influence has increased the probability of extreme heat events, and has likely changed the occurrence probabilities for some heavy precipitation events. The way a specific attribution question is posed and the conditions under which the question is addressed present persistent challenges for appropriately communicating attribution results to non-specialists. [ABSTRACT FROM AUTHOR]

We analyse seasonal and annual trends of extreme indices of air temperature and precipitation over Brazil during the period 1961–2018. The main goal is to investigate whether the climate is changing and if so, to explore if there is any marked seasonality in such changes. The daily observed datasets of maximum and minimum temperatures, and precipitation, are provided by the Brazilian National Institute of Meteorology and National Water Agency. We use the Sen Curvature and Mann‐Kendall statistical tests to compute the magnitudes and to evaluate the statistical significance of climate extremes trends, respectively. The results show that the warm extremes frequency of occurrence is increasing significantly while the opposite occurs for cold extremes, which reveals a very consistent and widespread warming over Brazil. The highest increases in warm extremes occur during austral spring and summer while for the cold extremes the greatest decreases are observed during austral winter. Unlike temperature, precipitation extremes show heterogeneous signals for most of the country. In Northeast Brazil, there are changes towards a drier climate, especially in summer and autumn. In the Southern region, the climate is becoming wetter, with a reduction in consecutive dry days, especially in spring. For the other regions, there is no strong clear change sign, but both positive and negative precipitation extreme trends, without statistical significance (mostly in Southeast Region). [ABSTRACT FROM AUTHOR]

We analyze annual extremes of daily maximum and minimum surface air temperature and of daily rainfall in East Asia and the Korean peninsula. This study made intensive use of the simulation data available from the CMIP5 (Coupled Model Intercomparison Project Phase 5) multimodels in historical and future experiments up to the year 2100, employing three different radiative forcings: RCP2.6, RCP4.5, and RCP8.5 (representative concentration pathways). Several reanalysis datasets are used to compare and evaluate the simulated climate extremes in the late twentieth century. We estimate the future changes in precipitation and temperature extremes in East Asia and Korea, and compare them to the global result, for the reference period 1986–2005. The rising rate of future cold extremes over East Asia and Korea is faster than that of warm extremes. This phenomenon appears more distinctly in Korea as a local scale, indicating more sensitivity of the Korean peninsula to global warming. The increase of the 20-year return level of maximum precipitation in the CMIP5 over East Asia by the end of twenty-first century is about 7% in the RCP2.6, 15% in the RCP4.5, and 35% in the RCP8.5 experiments, which exceed the corresponding global values. We also estimate the changes in precipitation extremes across East Asia as a function of the annual mean temperature variation at the same location. The CMIP5 sensitivity in maximum precipitation across East Asia is 5.5%/∘C, which is lower than the global figure (5.8%/∘C). The sensitivity for the Korean peninsula is 7.38%/∘C, indicating the strong impact of global warming to Korea. The results will be important in mitigating the detrimental effects of variations of climatic extremes and in improving the regional strategy for water resource and eco-environmental management, particularly for such areas in East Asia under significant changes in temperature and rainfall extremes. [ABSTRACT FROM AUTHOR]

Meteorological series (daily precipitation, minimum and maximum air temperature) for Asmara (Eritrea) for the last 100 years (1914–2015) are analysed. The data were quality‐controlled and homogenized using publicly available data from surrounding countries as well as newly recovered data from 12 stations in Eritrea. Overall, the Asmara data showed a consistent pattern and there were no outliers outside of four standard deviations from the corresponding reference. Climate indices were calculated using the program RClimDex. Overall, 8 indices for description of the air temperature data and 10 for precipitation data were calculated. The analyses of averages and indices reveal large climatic variations in the central highlands of Eritrea. The results indicate significant changes in air temperature since 1943, with daily minimum and maximum air temperature increasing at a similar rate of 0.22 and 0.19°C/decade, respectively. The diurnal air temperature range shows a non‐significant decreasing trend over the study period. No significant variation was found in the annual total and the seasonal precipitation over the last century. Significant trends were detected for some daily precipitation indices, although the lack of reference series prevents an evaluation of their reliability. [ABSTRACT FROM AUTHOR]

ABSTRACT: Observational analyses of changing climate extremes over the West Africa region have been limited by the availability of long and high‐quality datasets. To help address this gap, a climate extremes indices workshop was held in the Gambia in December 2011 with participants from 14 West African countries. The resulting analysis utilized 15 annual indices derived from observed daily temperatures and 10 annual indices derived from observed daily precipitation. The analysis was conducted for 166 meteorological stations in 13 countries for 2 periods: 1960–2010 and 1981–2010. The analyses of trends in the annual mean temperature indices have identified statistically significant increases of 0.16 °C/decade and 0.28 °C/decade for mean annual maximum and mean annual minimum temperatures, respectively, averaged over all available land stations in the region during the last 50 years. The seasonal‐temperature‐related indices show significant patterns of warming in all seasons. The annual mean of daily minimum temperature has increased more than the annual mean of daily maximum temperature leading to a decreasing trend in the diurnal temperature range. Warm days and warm nights have become more frequent, and cold days and cold nights have become less frequent. The analyses of precipitation‐based indices indicate spatially non‐coherent changes throughout the study area with few statistically significant trends over the longer period. Exceptions to this are the simple daily intensity index and maximum 5‐day precipitation, which show significant increasing regional trends over both the shorter and longer periods. Additionally, over the recent period (1981–2010) most of the precipitation related indices show significant trends towards wetter conditions. However, this period of increased rainfall follows a decade of significantly drier conditions in the region – it is not clear whether the recent upward trends reflect the ‘recovery’ from this long drought period or represents a long‐term response to warming. [ABSTRACT FROM AUTHOR]

This study investigates the variability of extreme rainfall (temperature) events in the twenty-first century based on 18 (24)-member multimodel simulations of models participating in phase 5 of the Couple Model Intercomparison Project (CMIP5). The study employed extreme indices defined by the WMO's Experts Team on Climate Change Detection Indices, under two radiative forcing scenarios: RCP4.5 and RCP8.5. Two 30-year time periods, mid- (2021-2050) and end (2071-2100) of the twenty-first century, are considered for investigation of extremes, relative to the baseline period (1961-1990). Mann-Kendall test statistic and Sen's slope estimator are used to investigate trend. Temperature shows a remarkable increase with an increase in radiative forcing. A sharp augmentation in temperature is projected towards the end of the twenty-first century. There will be almost zero cool days and cold nights by the end of the century. Very wet and extremely very wet days increase, especially over Uganda and western Kenya. Variation in maximum 1-day precipitation (R × 1 day) and maximum 5-day precipitation amount shows a remarkable increase in variance towards the end of the twenty-first century. Although the results are based on relatively coarse resolution data, they give likely conditions that can be utilized in long-term planning and be relied on in advanced studies. [ABSTRACT FROM AUTHOR]

ABSTRACT The temporal and spatial trends of four climate extreme indices for Guangdong Province of China were calculated based on observed daily precipitation, daily maximum, and daily minimum temperatures at 24 weather stations as well as the frequency of typhoon events during the period of 1957-2013. An integrated extreme climatic index ( IECI) was derived from four individual climate extreme indices (high temperature days ( Htd), low temperature days ( Ltd), intensive precipitation days ( Ipd) and number of typhoon events ( TT)), considering their weights using an information theory model. A simple linear regression model was utilized to analyze the spatiotemporal trends of the climate extremes. The correlation analysis between the above extreme climatic indices and the socioeconomic losses [affected area of crops ( AAC), direct losses of the economy ( DLE), and affected population ( AP)] was calculated. The results indicate that Htd increased while Ltd decreased significantly at the 5% significance level. By contrast, there were no significant long-term changes in Ipd and TT. The rate of change of IECI was 0.006 per decade and no long-term trend was detected in IECI. Spatially, a positive trend was observed in the Yuexi River Basin ( YXRB) for Ipd, while a negative trend was found in the East River Basin ( ERB). Ltd followed an opposite spatial pattern to that of Htd. Extreme temperature days occurred more frequently in the Pearl River Delta ( PRD) than in other parts of Guangdong Province. Regions with positive IECI rates of change were mostly in the YXRB, the coastal area of the Yuedong River Basin ( YDRB) and the northern and southern part of the ERB. The correlation coefficients between IECI and AAC, DLE, and AP are 0.375, 0.424 and 0.603, respectively. In general, IECI correlated more strongly with the loss indices caused by extreme climatic events than did the four individual extreme climatic indices. [ABSTRACT FROM AUTHOR]

ABSTRACT Ethiopia has wide eco-environmental diversity ranging from extreme heat at one of the lowest places in the world to one of the coolest summits in Africa. Associated with this environmental diversity and climate change, climatic extremes are expected to change over time and also vary across eco-environments in the country. This study was conducted to examine the trends of past precipitation and temperature extremes over three eco-environments in Ethiopia. The study involved analysis of 20 extreme indices computed from daily temperature and precipitation data spanning over 42 years (1967-2008). The climate data were obtained from 11 stations selected from three major eco-environments (pastoral, agropastoral and highland). The results indicated positive trends for maximum value of the maximum temperature ( TXx), warm days ( TX90p), warm nights ( TN90p) and warm spell duration indicators ( WSDI) and negative trends for cool days ( TX10p), cool nights ( TN10p) and cold spell duration indicators ( CSDI) in more than 8 of the 11 stations studied. However, most of the trends were not significant at many of the stations and the significant trends were not uniquely differentiated by eco-environments. Unlike temperature extremes, precipitation extreme trends showed high variability among nearby stations within eco-environments and were not significant at many of the stations studied. It is concluded that trends of temperature and precipitation extremes vary considerably among stations located within a given eco-environment indicating that the response of local climate to global warming could be different in physiographically diverse regions. [ABSTRACT FROM AUTHOR]

In this study, we assess the relationships between North Atlantic scale atmospheric regimes and extremes of precipitation and minimum temperature in the Iberian peninsula for an extended (DJFM) winter season. As found in previous studies, large scale atmospheric regimes are well represented in climate simulations while the extreme atmospheric variability is not. The relationship between some of these atmospheric regimes and the probability of occurrence of extreme values in simulations of present day climatic variability is validated here with daily observations at 68 meteorological stations all over the Iberian peninsula. Therefore, the possible changes in the probability of occurrence of winter extremes of minimum temperature and precipitation are obtained by projecting the changes in the probability of occurrence of the winter atmospheric regimes. The trends in the frequency of the observed large scale patterns give an indication of what can be expected in the next decades. For the long term (in a century), the changes are obtained directly from the comparison of the frequencies of the atmospheric regimes in the scenario simulations with those of the historical period. The projections obtained in this way are tested for consistency with the results obtained by comparing the changes in the extremes threshold values in the scenario with those of the historical simulations. The results point to a future with less precipitation extreme events and less minimum temperature extreme events in winter in the westerly central part of the Iberian peninsula. [ABSTRACT FROM AUTHOR]

This article presents a study regarding the trends in extreme daily temperature and precipitation near Lake Hövsgöl, Mongolia. From 1963 to 2002, a long-term set of daily maximum and minimum temperature and precipitation data are analyzed for the Lake Hövsgöl area in Mongolia. It examines eight indices of extreme precipitation and six indices of extreme temperature. Results revealed that climate conditions over northern Mongolia are changing as showed by a warming trend identified during the research period.

The mechanisms that drove zonal wind stress (τx) changes in the near-equatorial Pacific at the end of the extreme 1997–98 El Niño event are explored using a global atmospheric general circulation model. The analysis focuses on three features of the τx evolution between October 1997 and May 1998 that were fundamental in driving the oceanic changes at the end of this El Niño event: (i) the southward shift of near-date-line surface zonal wind stress (τx) anomalies beginning November 1997, (ii) the disappearance of the easterly τx from the eastern equatorial Pacific (EEqP) in February 1998, and (iii) the reappearance of easterly τx in the EEqP in May 1998. It is shown that these wind changes represent the deterministic response of the atmosphere to the observed sea surface temperature (SST) field, resulting from changes in the meridional structure of atmospheric convective anomalies in response to the seasonally phase-locked meridional movement of the warmest SST. The southward shift of the near-date-line τx anomalies at the end of this El Niño event was controlled by the seasonal movement of the warmest SST south of the equator, which—both directly and through its influence on the atmospheric response to changes in SST anomaly—brought the convective anomalies from being centered about the equator to being centered south of the equator. The disappearance (reappearance) of easterly EEqP τx has only been evident in extreme El Niño events and has been associated with the development (northward retreat) of an equatorial intertropical convergence zone (ITCZ). The disappearance/return of EEqP easterly τx arises in the AGCM as the deterministic response to changes in the SST field, tied principally to the changes in climatological SST (given time-invariant extreme El Niño SSTA) and not to changes in the underlying SSTA field. The disappearance (return) of EEqP easterly τx in late boreal winter (late boreal spring) is a characteristic atmospheric response to idealized extreme El Niño SST anomalies; this suggests that the distinctive termination of the 1997–98 El Niño event is that to be expected for extreme El Niño events. [ABSTRACT FROM AUTHOR]