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Important hydrological changes are observed in Serbia, as well as in many parts of the world. Many national and international projects and studies address climate change and its impact on water resources. Some focus solely on the impact of climate change, while others also assess the impact of land use changes and/or changes in human use of water. Due to differences in climate change and human activities, the different climate and hydrological trends are obtained for the different regions in Serbia. This paper presents the past longterm temperature, precipitation and river discharge trends across Serbia. Second, more important aim of the research, is to assess and forecast average relationships between an increase in air temperature and changes in river discharges and precipitation. This relation could help us to find appropriate regional climate and hydrological models. Even within a single catchment, depending on the regional models used, the initial and other assumptions made, and the impacts assessed, the differences between the results can be small but often significant, too. The reliability of the projections receives little or no consideration. This paper also discusses this topic and attempts to provide some guidelines. [ABSTRACT FROM AUTHOR]

This paper matched the data for all non-financial listed firms in China from 1990 to 2017 with weather data and used temperature and precipitation to represent climate change. Using daily temperature and daily precipitation data, we constructed temperature bins and precipitation bins. This study presents a potential first empirical analysis that applies the risk perception theory to comprehensively examine the impacts of daily temperature and daily precipitation on firms' debt financing costs. Compared to a day with a suitable temperature, a day with temperatures above 30 °C increases firms' debt financing costs by 0.2411%. Compared to a sunny day, a day with torrential rain increases firms' financing costs by 0.2697%. Approximately $122.13 million and $20.49 million in extra costs were incurred across all firms in 2017. We conducted a series of heterogeneity tests. We found that the negative impacts of climate change on debt financing costs are greater for firms that investor considers more vulnerable. Finally, we found two possible mechanisms. First, from the firm's subjective initiative perspective, firms that respond proactively during seasons of high temperatures and heavy rains can reduce the negative impacts. Second, adverse weather caused by climate change may also increase firms' debt financing costs by blocking travel. These results enrich the literature on firms' debt financing costs and contribute to the understanding of climate change's impact on firms. [Display omitted] • An extra high-temperature day increases firms' debt financing cost by 0.2411%. • An extra heavy-rain day increases firms' debt financing costs by 0.2697%. • The negative impacts will be greater for those firms that investor considers more vulnerable. • Firms' response proactively can reduce the negative impacts. • Climate change also may increase firms' debt financing costs by blocking travel. [ABSTRACT FROM AUTHOR]

Attempts to analyze the effect of weather shocks on livestock production have been carried out using integrated assessment models (IAMs) or the cross-sectional (Ricardian) method. However, these methodologies are fraught with obvious shortcomings, such as omitted variable bias, amongst others. This paper, therefore, re-examines the relationship between weather changes and global livestock production using an established econometric strategy that takes care of the pitfalls inherent in the conventional approaches. Using country-level data and a variety of specifications, we find that a 1 °C increase in temperature will lead to a 9.7% reduction in global beef production on average. These adverse effects are amplified in hot, poor, and agriculture-dependent countries. Besides, we find that a marginal increase in annual precipitation would lead to a 2.1% increase in beef production in tropical countries but a 1.9% decrease in temperate ones. Also, our forecasts show that climate change will reduce animal output by a further 20% in the mid-century and an additional 40% by the end of the century assuming no adaptation other than the degree of adaptation observed in the historical period. • Temperature and precipitation affect global livestock production nonlinearly • The effect of warming is amplified in hot, poor, and agriculture-dependent countries • Rise in rainfall appears to be more favorable to livestock production in the tropics • Future weather projections suggest a further drop in global livestock production [ABSTRACT FROM AUTHOR]

Permafrost is very sensitive to climate factors, with warm permafrost particularly vulnerable to climate change. This paper aims to provide a detailed case study of climate trends of a high-latitude Alaskan site underlain by warm permafrost based on historical data and predictions from the Coupled Model Intercomparison Project Phase 5 (CMIP5). The climate data, including air temperature, precipitation, wind speed, and their annual and seasonal trends from 1950 to 2099, are presented for Bethel, Alaska. The downscaled data are compared with the historical data in the overlap period. Both air and design freezing and thawing indices are calculated using various methods. In comparison, the downscaled model predictions align well with air temperature and wind speed records but not for precipitation, indicating the need for further downscaling at a finer resolution. The historical annual temperature records show a warming rate of 0.40 °C per decade, which is predicted to almost double to 0.78 °C per decade in the 21st century, leading to shorter winters and longer summers. The historical annual precipitation increased by a rate of 14.8 mm per decade from 1950 to 2020, and this trend is predicted to continue but at a slightly lower rate. The wind speed decreased consistently from 1984 to 2020 by 0.9 km/h per decade. However, the CMIP5 predicts that such a trend will diminish, with the mean annual wind speed remaining almost unchanged in this century. The air freezing index exhibits a consistent downtrend from 1950 to 2020, whereas the air thawing index remained flat until 1980 and rose afterward; the CMIP5 predicts that both trends will continue in the 21st century. The design air freezing and thawing indices are sensitive to the assessment periods for both methods. An assessment period shorter than 30 years, e.g., ten years, is recommended to find design indices. It is conservative to use the monthly mean air temperature method for evaluating the design air freezing index and apply the extreme event method for the design thawing index. • Compare downscaled model data at a finer resolution with other models in CMIP5. • Assess the design freezing and thawing indices by two methods with varying periods. • Recommend methods and periods for evaluating design freezing/thawing indices. • Discuss climate change effects on infrastructure, design strategies, future studies. [ABSTRACT FROM AUTHOR]

[Display omitted] • As compared to precipitation, soil moisture greatly influences GPP. • There is a solid spatial agreement among PUE and SWUE with a step-wise gradient from southwest to northeast. • PUE and SWUE are relatively low in extremely arid and humid regions. • In relatively moderate areas, PUE and SWUE increase with the abundance of moisture conditions. • Meadow grassland has the highest PUE and SWUE, followed by typical grassland and desert steppe. Grassland ecosystem dominates in the Mongolian Plateau, mostly located in its arid and semi-arid regions. Although the ecosystem is an important source for agriculture, it is also a fragile system ecologically. This system is one of the most sensitive areas to global climate change. Precipitation (PPT) and soil moisture (SM) are important water sources in the grassland ecosystem, and their changes would greatly affect vegetation growth. This paper generates the precipitation use efficiency (PUE) and soil water use efficiency (SWUE) of Mongolian Plateau grassland based on multi-source remote sensing data to investigate the spatio-temporal distribution pattern and identify the driving factors. Results showed four main findings. Firstly, two water use efficiency (WUE) indicators show a generally increasing trend from 2000 to 2018, with average PUE and SWUE 1.07 gC·m−2·mm−1 and 1.03 gC/kg·H 2 O, respectively. They have similar spatial distribution patterns, consistent with the available water resources, decreasing from northeast to southwest. However, grassland vegetation growth is more sensitive to soil moisture than precipitation, and the dynamic change of SWUE is smoother and more significant than PUE. Secondly, due to the higher species richness, better vegetation biological characteristics and less severe growth environment, meadow grassland has the highest PUE and SWUE, followed by typical grassland and desert steppe. Thirdly, PUE and SWUE are relatively low in extremely arid and humid regions. In areas with relatively moderate water conditions (PPT in 148–360 mm, SM in 0.14–0.35 cm3/cm3), two indicators increase with the abundance of moisture conditions and reach the maximum. Fourthly, there is a positive linear relationship between PUE (SWUE) with precipitation and a unimodal correlation between PUE (SWUE) with temperature across the entire grassland. However, a varying correlation exists in different grassland ecosystems, especially meadow grassland. Together with analyzing past and future trends, this study provides strong evidence to reflect the impact of global climate change and the management and protection of the grassland ecosystems in arid and semi-arid regions. [ABSTRACT FROM AUTHOR]

The assessment of future precipitation variations prevailing in an area is essential for the research regarding climate and climate change. The current paper focuses on 3 selected areas in Greece that present different climatic characteristics due to their location and aims to assess and compare the future variation of annual and seasonal precipitation. Future precipitation data from the ENSEMBLES anthropogenic climate-change (ACC) global simulations and the Climate version of the Local Model (CLM) were obtained and analyzed. The climate simulations were performed for the future periods 2021–2050 and 2071–2100 under the A1B and B1 scenarios. Mann–Kendall test was applied to investigate possible trends. Spatial distribution of precipitation was performed using a combination of dynamic and statistical downscaling techniques and Kriging method within ArcGIS 10.2.1. The results indicated that for both scenarios, reference periods and study areas, precipitation is expected to be critically decreased. Additionally, Mann–Kendall test application showed a strong downward trend for every study area. Furthermore, the decrease in precipitation for the Ardas River basin characterized by the continental climate will be tempered, while in the Sperchios River basin it will be smoother due to the influence of some minor climatic variations in the basins' springs in the highlands where milder conditions occur. Precipitation decrease in the Geropotamos River basin which is characterized by Mediterranean climate will be more vigorous. B1 scenario appeared more optimistic for the Ardas and Sperchios River basins, while in the Geropotamos River basin, both applied scenarios brought similar results, in terms of future precipitation response. [ABSTRACT FROM AUTHOR]

Precipitation is one of the most important climate variables which can impact the urban water and urban flooding. Thus, knowledge of precipitation and precipitation extremes is important to manage urban water and to design urban drainage infrastructure to reduce the urban flooding. This paper presented trends in precipitation and precipitation extremes in Ho Chi Minh City for the 1980-2013 period based on the precipitation data obtained from nine rain gauges. Non-parametric test, i.e. Mann-Kendall test, was used for trend analysis, and the precipitation extremes indices were used to calculate the extreme events. The results indicated that the precipitation has increasing trend in the northwest part of the city and decreasing trend in the southeast part of the city in the 1980-2013 period. In addition, the precipitation and precipitation extremes had generally increasing trends. The results obtained in this study can be used for urban water management and sustainable urban drainage system in Ho Chi Minh City. [ABSTRACT FROM AUTHOR]

The most important anthropogenic influences on climate are the emissions, changes in land use, such as urbanization aural areasnd agriculture. The urban environment has distinctive bioclimatical factors in relation to rural areas. The process of urbanization alters natural surface and atmospheric conditions. Urban areas are characteristic by increased rainwater surface runoff, increased temperatures and decreased evaporation. Exactly evaporation warms the rural surface more than the urban. The paper concerns on the impacts of urbanization that are evaluated by observations in cities with those in rural areas – not so populated and with smaller built areas. We use and asses the difference between trends in monthly average temperatures and trends in monthly precipitations in the cities and the corresponding trends in rural areas. For the trend analysis, the Mann-Kendall nonparametric test is used. Our results show differences in trends in villages and cities. Observed are increased trends in temperature and decreased trends in precipitation due to urban and land-use changes. [ABSTRACT FROM AUTHOR]

Abstract: The Arctic Oscillation (AO) has been found in previous studies to be a major synoptic factor affecting the climate of many regions in the high and mid-latitudes. This paper demonstrates the physical process by which the AO affects the climate of the Eastern Mediterranean basin, with a focus on precipitation in Israel as a case study. It is shown that a trend of increasing AO is associated with a substantial decrease of winter precipitation from the Iberian Peninsula, though Italy, Greece, Turkey and Cyprus, as well as Lebanon, Syria and also the northern parts of Israel. Winter rain is slightly increased in the southern coast of the eastern half of the Mediterranean Sea. The immediate meteorological causes are shown to be a larger northerly component of the flow over the Mediterranean Sea, associated with a decreasing relative humidity and stability, except over the southern coast, where the air mass has the longest track over the relatively warm water. We suggest here that the observed changes in air flow that drives the precipitation trends can be explained by shifts in the AO that can be partially explained by increasing greenhouses gases. Results from the IPCC multi climate models show that the AO will continue to increase during the 21st century. This increase may lead to a continuation of the trends discussed here. The importance of the analysis provided here is in pointing out the possibility that processes that have been predicted by global warming and changes in global circulation have already started to affect precipitation and major water resources in the Mediterranean basin. [Copyright &y& Elsevier]

This paper explored the projected changes in precipitation, maximum temperature (T max), and minimum temperature (T min) over the Yangtze River Basin (YRB) based on 23 Global climate models (GCMs) from the Coupled Model Intercomparison Project phase 6 (CMIP6). The Empirical Quantile Mapping (EQM) approach was firstly applied to correct the biases in the GCMs. Next, the future changes were investigated by analyzing the multi-model ensemble (MME) of the bias-corrected dataset during 2025–2044 (near-term), 2045–2064 (mid-term), and 2081–2100 (long-term) periods, with reference to the baseline period 1995–2014, under three integrated scenarios (SSP1-2.6, SSP2-4.5, and SSP5-8.5) of the Shared Socioeconomic Pathways (SSPs) and the Representative Concentration Pathways (RCPs). Results show that: (1) the biases in CMIP6 GCMs can be effectively corrected by EQM, and the MME performs better than individual models for each climatic variable. (2) Precipitation over the YRB from 2025 to 2100 is projected to increase at the rate of 9.66 mm/decade, 13.45 mm/decade, and 21.01 mm/decade under SSP1‐2.6, SSP2‐4.5, and SSP5‐8.5, respectively. In the long-term, the annual precipitation is projected to increase by 10.41%, 10.66% and 15.80%, under SSP1‐2.6, SSP2‐4.5 and SSP5‐8.5, respectively. (3) T max (T min) over the YRB is projected to increase by 0.09 (0.07) °C/decade, 0.29 (0.27) °C/decade, and 0.66 (0.64) °C/decade under SSP1‐2.6, SSP2‐4.5, and SSP5‐8.5, respectively. In the long-term, T max (T min) averaged over the YRB is projected to increase by 1.75 (1.50) °C, 2.72 (2.54) °C and 5.04 (4.85) °C under SSP1‐2.6, SSP2‐4.5 and SSP5‐8.5, respectively. (4) Uncertainties in the projected precipitation and temperature over the YRB were reduced based on MME. But further researches, such as selecting the superior models with respect to the regional climate of the YRB from the CMIP6 and using the ensemble methods that assign weight based on the performance of each model, are still needed to provide more reliable climate projections. • Projected changes were explored by 23 CMIP6 GCMs under the three SSP-RCP scenarios. • Biases in the GCMs were corrected by Empirical Quantile Mapping (EQM) method. • Multi-model ensemble (MME) was used to reduce the uncertainties. [ABSTRACT FROM AUTHOR]

Abstract: Investigation of hydrological impacts of climate change at the regional scale requires the use of a downscaling technique. Significant progress has already been made in the development of new statistical downscaling techniques. Statistical downscaling techniques involve the development of relationships between the large scale climatic parameters and local variables. When the local parameter is precipitation, these relationships are often very complex and may not be handled efficiently using linear regression. For this reason, a number of non-linear regression techniques and the use of Artificial Neural Networks (ANNs) was introduced. But due to the complexity and issues related to finding a global solution using ANN-based techniques, the Genetic Programming (GP) based techniques have surfaced as a potential better alternative. Compared to ANNs, GP based techniques can provide simpler and more efficient solutions but they have been rarely used for precipitation downscaling. This paper presents the results of statistical downscaling of precipitation data from the Clutha Watershed in New Zealand using a non-linear regression model developed by the authors using Gene Expression Programming (GEP), a variant of GP. The results show that GEP-based downscaling models can offer very simple and efficient solutions in the case of precipitation downscaling. [Copyright &y& Elsevier]

Abstract: According to precipitation and evaporation time series in Yuyang region, this paper adopts Morlet wavelet analysis method, analyzes time series configuration in detail, and discusses multi-scale variations and mutation of precipitation and evaporation. The result shows that, precipitation and evaporation series exist multi-scale characteristic, the main period is 16y and 15y, secondary period is 3y, 7y, and 9y. Period changes complicatedly, large scale comprises small scale; oscillation point of a=16y and a=15y delays 3∼4y compared with a=9y; precipitation oscillation point delays 1y compared with evaporation; in deferent time scale oscillation point is deferent comparison with evaporation, precipitation oscillation point appearance in the Late 1980s and 1990s, evaporation time series oscillation point appearance in Mid 1980s and Mid and Late 1990s. [Copyright &y& Elsevier]

Elevated world temperatures, as forecasted by the 4th IPCC report, are expected to increase the hydrological cycle activity, leading to a change in precipitation patterns and increase in evapotranspiration. These in turn are expected to affect river runoff and water variability, depending on basin latitude. In this paper, we assess the impact of water supply variability on ‘treaty cooperation’ (defined here as the likelihood of treaty formation and number of treaties formed) between international bilateral river basin riparian states. The water variability measure that we use captures both annual runoff variability and precipitation variability. We employ additional control variables adopted from economic and international relations theories on international cooperation. The main results suggest that water supply variability in international bilateral basins creates an impetus for cooperation. Our results support an inverted U-shaped relationship between water supply variability and treaty cooperation. Similarly, interactions between the states in the form of diplomatic and trade relations support cooperation. Various measures of democracy/governance suggest different impacts on cooperation. Uneven economic power between the riparian states inhibits treaty cooperation. The geography variables we use are insignificant in all the estimated relationships. [Copyright &y& Elsevier]

Abstract: The paper discusses the frequency of precipitation, broken down into amount categories, on thunderstorm days in Poland during the period 1951–2000. The authors looked at the number of thunderstorm days with precipitation versus the total thunderstorm days. Frequencies of certain precipitation totals on thunderstorm days were determined for various Polish regions, as well as long-term and annual precipitation variabilities. Daily precipitation and thunderstorm observation records from 47 Polish weather stations were used in the study. Precipitation on thunderstorm days was broken down into the following categories: dry day or trace precipitation, 0.1–10.0 mm, 10.1–20.0 mm, 20.1–30.0 mm, and more than 30.0 mm. These categories were studied for variability in five thunderstorm regions in Poland. The study revealed at that precipitation occurred on most of the thunderstorm days in the second half of the 20th century in Poland (on average 85% of cases). On 63% of thunderstorm days there was between 0.1 and 10.0 mm of rain. Cases of more than 30.0 mm of precipitation were very rare (2.7%) and were recorded mostly in mountainous areas. Annual frequencies of the various precipitation categories were similar across all of the regions. There was more variability in the long-term view, but in most cases no clear trend could be established. Slight decrease in number of thunderstorm days without precipitation (statistically significant in regions II and III) and an increase in days with the lowest precipitation, 0.1–10.0 mm (statistically significant in region V) was stated. [Copyright &y& Elsevier]

Plant species occurrence in Europe is affected by changes in nitrogen deposition and climate. Insight into potential future effects of those changes can be derived by a model approach based on field-based empirical evidence on a continental scale. In this paper, we present a newly developed empirical model PROPS, predicting the occurrence probabilities of plant species in response to a combination of climatic factors, nitrogen deposition and soil properties. Parameters included were temperature, precipitation, nitrogen deposition, soil pH and soil C/N ratio. The PROPS model was fitted to plant species occurrence data of about 800,000 European relevés with estimated values for pH and soil C/N ratio and interpolated climate and modelled N deposition data obtained from the Ensemble meteo data set and EMEP model results, respectively. The model was validated on an independent data set. The test of ten species against field data gave an average Pearson's r-value of 0.79. PROPS was applied to a grassland and a heathland site to evaluate the effect of scenarios for nitrogen deposition and climate change on the Habitat Suitability Index (HSI), being the average of the relative probabilities, compared to the maximum probability, of all target species in a habitat. Results for the period 1930–2050 showed that an initial increase and later decrease in nitrogen deposition led to a pronounced decrease in HSI, and with dropping nitrogen deposition to an increase of the HSI. The effect of climate change appeared to be limited, resulting in a slight increase in HSI. Image 1 • The probability of Plant species on an European scale can be simulated by new model named PROPS. • Increase of nitrogen deposition leads to a significant decrease of biodiversity. • The effect of climate change seems relatively small. • Climate change leads to a slight increase of biodiversity in the Netherlands. • The habitat suitability index calculation should be updated with unwanted species. [ABSTRACT FROM AUTHOR]

The African Sahel provides the most dramatic example of multi-decadal climate variability that has been quantitatively and directly measured. Annual rainfall across this region fell by between 20 and 30 percent between the decades leading up to political independence for the Sahelian nations (1930s to 1950s) and the decades since (1970s to 1990s). Climatic perspectives on the nature and causes of this period of desiccation have changed and, in some cases, matured as the years -- and the drought -- continued. This paper reviews these changing perspectives and reflects on three central questions: How unique an occurrence has been this desiccation in the recent human history of the Sahel? Can we find an adequate explanation for this desiccation in the natural forces that shape the climate system, or do we have to implicate human interventions in the system? Is our understanding of climate variability sufficient to allow us to develop seasonal rainfall forecasting capabilities for the region? [ABSTRACT FROM AUTHOR]

By 2025, it is estimated that around 5 billion people, out of a total population of around 8 billion, will be living in countries experiencing water stress (using more than 20% of their available resources). Climate change has the potential to impose additional pressures in some regions. This paper describes an assessment of the implications of climate change for global hydrological regimes and water resources. It uses climate change scenarios developed from Hadley Centre climate simulations (HadCM2 and HadCM3), and simulates global river flows at a spatial resolution of 0.5x 0.5 deg. using a macro-scale hydrological model. Changes in national water resources are calculated, including both internally generated runoff and upstream imports, and compared with national water use estimates developed for the United Nations Comprehensive Assessment of the Freshwater Resources of the World.Although there is variation between scenarios, the results suggest that average annual runoff will increase in high latitudes, in equatorial Africa and Asia, and southeast Asia, and will decrease in mid-latitudes and most subtropical regions. The HadCM3 scenario produces changes in runoff which are often similar to those from the HadCM2 scenarios // but there are important regional differences. The rise in temperature associated with climate change leads to a general reduction in the proportion of precipitation falling as snow, and a consequent reduction in many areas in the duration of snow cover. This has implications for the timing of streamflow in such regions, with a shift from spring snow melt to winter runoff. Under the HadCM2 ensemble mean scenario, the number of people living in countries with water stress would increase by 53 million by 2025 (relative to those who would be affected in the absence of climate change). Under the HadCM3 scenario, the number of people living in countries with water stress would rise by 113 million. However, by 2050 there would be a net reduction inp [ABSTRACT FROM AUTHOR]