Annual Average Surface Temperature Research Articles

Prediction on the spatial distribution of the seropositive rate of schistosomiasis in Hunan Province, China: a machine learning model integrated with the Kriging method.

Schistosomiasis remains a formidable challenge to global public health. This study aims to predict the spatial distribution of schistosomiasis seropositive rates in Hunan Province, pinpointing high-risk transmission areas and advocating for tailored control measures in low-endemic regions. Six machine learning models and their corresponding hybrid machine learning-Kriging models were employed to predict the seropositive rate. The optimal model was selected through internal and external validations to simulate the spatial distribution of seropositive rates. Our results showed that the hybrid machine learning-Kriging model demonstrated superior predictive performance compared to basic machine learning model and the Cubist-Kriging model emerged as the most optimal model for this study. The predictive map revealed elevated seropositive rates around Dongting Lake and its waterways with significant clustering, notably in the central and northern regions of Yiyang City and the northeastern areas of Changde City. The model identified gross domestic product, annual average wind speed and the nearest distance from the river as the top three predictors of seropositive rates, with annual average daytime surface temperature contributing the least. In conclusion, our research has revealed that integrating the Kriging method significantly enhances the predictive performance of machine learning models. We developed a Cubist-Kriging model with high predictive performance to forecast the spatial distribution of schistosomiasis seropositive rates. These findings provide valuable guidance for the precise prevention and control of schistosomiasis.

A century-long tendency of change in surface air temperature on the territory of Ukraine

A century-long tendency of change in surface air temperature on the territory of Ukraine

The Dust Planet Clarified Modelling Martian MY29 Atmospheric Data Using the Dynamic-Atmosphere Energy-Transport (DAET) Climate Model

The Dynamic Atmosphere Energy Transport (DAET) climate model, a mathematical model previously applied to a study of Earth’s climate, has been adapted to study the climatic features in the low-pressure, dust-prone atmosphere of the planet Mars. Using satellite data observed for Martian Year 29 (MY29), temperature profiles are presented here thatconfirm the studies of prior authors of the existence on Mars of a tropical solar-energy driven zone of daytime atmospheric warming, that both diurnally lifts the tropopause and follows the annual latitudinal cycle of the solar zenith. This tropical limb of ascending convection is dynamically linked to polar zones of descending air, the seasonal focus of which is concentrated over each respective hemisphere’s polar winter cap of continuous darkness. An analysis of the MY29 temperature data was performed to generate an annual average surface temperature metric that was then used to both inform the design of and to constrain the computation of the DAET climate model. The modelling analysis suggests that the Martian atmosphere is fully transparent to surface emitted thermal radiant energy. The role of lit hemisphere surface reflectance provides an energy boost to the dust-prone surface boundary layer at grazing-angle latitudes. This backlighting process of quenched solar energy capture ensures that the Martian climate operates as a black-body system. The high emissivity solar illuminated hemispheric surface heats the atmosphere by direct thermal conduction followed by a process of adiabatic convection across the planetary surface. It is the non-lossy process of adiabatic convection that results in the development and maintenance of a flux-enhanced atmospheric energy reservoir which accounts for the 2 Kelvin Atmospheric Thermal Effect in the Martian troposphere.

Evaluating the Performance of the Greenbelt Policy in Beijing Using Multi-Source Long-Term Satellite Observations from 2000 to 2020

Beijing is among the first cities in China to implement a greenbelt policy to improve urban vegetation, which plays a crucial role in enhancing the urban ecological environment. The policies have shown remarkable results. However, long-term evaluation of the performance of the greenbelt policies in Beijing has not been carried out in order to quantitatively evaluate their effectiveness. In this study, long-term satellite observations of the normalized difference vegetation index (NDVI), land surface temperature, precipitation, and night-light from 2000 to 2020 are used to investigate the spatio-temporal variabilities in NDVI and explore the mechanisms of the impacts of the greenbelt policies in Beijing. The main results are as follows: (1) From 2000 to 2020, the overall NDVI in Beijing exhibited an upward trend, with the proportion of high-NDVI (>0.8) areas increasing from 26.18% in 2000 to 53.64% in 2020. The proportion of low-NDVI (<0.2) areas continued to decrease from 0.64% in 2000 to 0.2% in 2020. (2) The 1st Greenbelt Zone shows a significant increase in its NDVI (with an average increase of 0.296 units in the NDVI at district level), indicating that the policy’s implementation had a notable effect, while the 2nd Greenbelt Zone was mainly in a degraded state and a declining trend, indicating that its performance fell short of expectations. (3) During the preparation for the 2008 Summer Olympics, while the 1st Greenbelt Zone had a slightly negative effect on NDVI improvement, probably due to urban re-construction, the 2nd Greenbelt Zone showed a significant positive effect, leading to an increase of 0.013 units in the NDVI at district level. In addition, the correlation analysis shows that an increase in annual average land surface temperature leads to a decrease in the NDVI, while annual precipitation has a positive relationship with NDVI changes. This study highlights the importance of long-term satellite observations in evaluating the performance of greenbelt policies in Beijing. The evaluation approach developed in this study can be readily applied to similar cities globally.

Identifying determinants for the seropositive rate of schistosomiasis in Hunan province, China: A multi-scale geographically weighted regression model.

Schistosomiasis is of great public health concern with a wide distribution and multiple determinants. Due to the advances in schistosomiasis elimination and the need for precision prevention and control, identifying determinants at a fine scale is urgent and necessary, especially for resource deployment in practice. Our study aimed to identify the determinants for the seropositive rate of schistosomiasis at the village level and to explore their spatial variations in local space. The seropositive rates of schistosomiasis were collected from 1714 villages or communities in Human Province, and six spatial regression models including ordinary least squares (OLS), spatial lag model (SLM), spatial error model (SEM), geographically weighted regression (GWR), robust GWR (RGWR) and multiscale GWR (MGWR) were used to fit the data. MGWR was the best-fitting model (R2: 0.821, AICc:2727.092). Overall, the nearest distance from the river had the highest mean negative correlation, followed by proportion of households using well water and the annual average daytime surface temperature. The proportions of unmodified toilets showed the highest mean positive correlation, followed by the snail infested area, and the number of cattle. In spatial variability, the regression coefficients for the nearest distance from the river, annual average daytime surface temperature and the proportion of unmodified toilets were significant in all villages or communities and varied little in local space. The other significant determinants differed substantially in local space and had significance ratios ranging from 41% to 70%, including the number of cattle, the snail infested area and the proportion of households using well water. Our study shows that MGWR was well performed for the spatial variability of schistosomiasis in Hunan province. The spatial variability was different for different determinants. The findings for the determinants for the seropositive rate and mapped variability for some key determinants at the village level can be used for developing precision intervention measure for schistosomiasis control.

Evaluation of the efficiency of sorbents for accidental oil spill response in the Arctic waters

The development and operation of new oil fields on the Arctic shelf increases the risks of oil spills, which require the use of oil spill response tools and materials that are efficient in harsh climatic conditions. The question of actual efficiency of sorbents for reducing the level of oil pollution in the conditions of the Arctic and subarctic waters is relevant. The work is aimed at a comparative study of the efficiency of sorbents of mineral and organic origin used by coastal enterprises in the Kola Bay as well as a sorbent based on chitin in model systems simulating real conditions in sea waters. The characteristics of sorption agents were determined applying ASTM F716-18 procedure. Sorption capacity was evaluated in respect of ARCO grade oil, diesel fuel and marine oil. The efficiency of sorbents was estimated in model systems “sea water – oil” at water temperature corresponding to the average annual surface temperature in the Barents Sea. Actual data on sorption capacity of commercial sorbents “Lessorb”, “Novosorb”, a sorbent based on vermiculite and chitin sorbent in relation to potential pollutants of waters were obtained. The dynamics of sea water saturation with oil products at –0.5 (±1) and 10 (±1) °С was determined. It is shown that at higher temperature the concentration of oil products in sea water column (in the presence of an oil film on the surface) is on average four times higher than at low temperature. Kinetic dependences were obtained that describe the content of oil products in water column and near-surface layer of sea water in the presence of the studied sorbents at 5 (±1) °C, corresponding to the average annual temperature in the Kola Bay of the Barents Sea. A method is proposed for evaluating the efficiency of sorbents from the values of regression coefficients characterizing the dependence of oil products content in sea water on the character of sorbent and duration of its action.

Experimental and Numerical Investigations on an Organic Phase Change Material Incorporated Cool Concrete Pavement

Background: Traditionally, cool pavements have been designed as reflective, evaporative, etc. Though the reflective pavements reduce the pavement surface temperature significantly, they increase glare, the thermal burden on pedestrian traffic, and the temperature of nearby buildings. In the case of evaporative pavements, the absence of water, reduced thermal inertia and solar reflection result in a higher pavement temperature. As a result, there has been a pressing need to investigate new low-side-effect cool pavement options. Objective: The study aims to analyze the effect of phase change material (PCM) incorporation on the thermal performance of concrete pavements and to develop a total enthalpy-based numerical heat transfer model for such cool pavements. Materials and Methods: A paraffin-based organic PCM with a melting point of 42 to 45 °C was used in this work, and expanded clay aggregate (ECA) was used as an encapsulation medium. Concrete slabs without and with the incorporation of PCM-impregnated ECAs were cast, and thermocouples were implanted in the concrete to monitor the pavement temperature continuously. A total enthalpy-based numerical heat transfer model was developed to predict the thermal performance of such cool concrete pavements. Results: The PCM incorporation reduced 2.24 °C in the annual average pavement surface temperature with a maximum reduction of 4.12 °C. Conclusion: PCM incorporation effectively reduces pavement surface temperature during the daytime and makes the pavements cooler. Increasing the encapsulating medium's porosity and the concrete slab's thermal conductivity enhances the cooling potential. However, the thermal characteristics of the encapsulating material may be neglected as their impact is less on the cooling potential.

Environmental Determinants for Snail Density in Dongting Lake Region: An Ecological Study Incorporating Spatial Regression.

This study explored the environmental determinants of different months on snail density measured in April at different types of snail habitats (marshlands, inner embankments, and hills) by considering spatial effects. Data were gathered from surveys on snails that were conducted in Hunan Province in April 2016, and information was collected on environmental variables. To investigate the environmental factors influencing snail density in various types of snail habitats, the ordinary least square model, spatial lag model, and spatial error model were all used. The environmental determinants for snail density showed different effects in the three types of snail habitats. In marshlands, snail density measured in April was associated positively with the normalized difference vegetation index (NDVI) and was associated negatively with flooding duration and annual hours of sunshine. Extreme temperatures correlated strongly to snail density measured in April (P < 0.05). In areas inside embankments, snail density measured in April increased with a decreased distance between snail habitat and the nearest river (P < 0.05). In hills, extreme heat, annual hours of sunshine, NDVI in September, and annual average land surface temperature (LST) were associated negatively with snail density measured in April, whereas index of moisture (IM) was associated positively with snail density measured in April (P < 0.05). The effects of LST and hours of sunshine on snail density measured in April varied with months of the year in the three different types of snail habitats (P < 0.05). Our study might provide a theoretical foundation for preventing snail transmission and subsequent spread of schistosomiasis.

Integrating In Situ and Current Generation Satellite Data for Temporal and Spatial Analysis of Harmful Algal Blooms in the Hartbeespoort Dam, Crocodile River Basin, South Africa

The Hartbeespoort Dam is a discharge point of a catchment that is characterized by urbanization, mining, industrial, and agricultural activities. These activities coupled with fluxes of heavily polluted wastewater from informal settlements, wastewater treatment works, as well as runoff from golf courses have led to the development of recurring harmful algal blooms (HABs). The predominant cyanobacteria scum that is largely covering the Dam water is toxic to fish and poses serious public health risks. Phosphorus is the limiting nutrient in terrestrial aquatic systems and excess concentration in the waters usually results in eutrophication. The productivity level in Hartbeespoort Dam is also a function of total phosphorous (TP) level, showing a positive correlation with chlorophyll-a, an index for phytoplankton which are predominantly HABs in this Dam. Analysis of long-term in situ water quality data (1980–2020) show that TP is not the only driver, changes in surface water temperatures also affect the productivity level, especially, when TP levels are below a threshold of approximately 0.4 mg/L. Chlorophyll-a was retrieved from current generation high resolution satellite (Landsat and Sentinel) at 5-year interval. Standard band ratio-based ocean color model applied to satellite data produced an accuracy of R2 = 0.86 and RMSE of 5.56 µg/L. Time series analysis of in situ and satellite data show similar trends including capturing the effect of biocontrol on productivity levels between the late 1980s and the early 1990s, after which productivity increased with an increased flux of TP. Since 2015, the average annual surface temperature in the Dam has decreased leading to the decline in productivity level despite increasing levels of TP. The spatial dynamics of the HABs is a function of the discharges levels of the various rivers draining into the Dam as well as its geometry. Relatively higher concentrations are observed near river discharges and in areas of restricted water circulation.

Gravel parameterization scheme and verification using BCC_CSM

The soil in China contains an abundance of gravels, but it is poorly described in land surface models. To solve this problem, the Beijing Climate Center Atmosphere–Vegetation Interaction Model (BCC_AVIM), which is a land surface model with the gravel parameterization, is coupled to the Beijing Climate Center Climate System Model (BCC_CSM). The simulation ability of BCC_CSM for China using the gravel parameterization is evaluated by comparing the simulation results using default and new schemes with the observed data. The results show that the annual average surface temperature simulated with the new schemes is more consistent with the observation in terms of spatial distribution, and the simulation results are significantly improved, especially in summer. From the perspective of the area-averaged variables, more precipitation simulated using the default schemes is improved except for summer. The high-level and low-level wind fields simulated by BCC_CSM significantly improve the Qinghai-Tibet Plateau. In general, this gravel parameterization is more suitable for areas with high gravel content, and it improves the simulation performance of BCC_CSM in some areas of China.

Suitability of human settlements in mountainous areas from the perspective of ventilation: A case study of the main urban area of Chongqing

Based on the multi-source data (e.g., building vector and remote sensing data) of the main urban areas of Chongqing, China, this study selected a few natural factors—the relief degree of the land surface (RDLS), land cover index (LCI), annual average land surface temperature (LST), water resource index (WRI), and frontal area index (FAI)—and used the geographic information system spatial analysis method to quantitatively investigate the spatial variation in the suitability of human settlements in mountainous areas from the perspective of ventilation. The study findings can be summarized as follows: 1) The population distribution in the main urban areas of Chongqing is affected by, in descending order, the LCI, FAI, RDLS, WRI, and LST. 2) In the main urban areas of Chongqing, the RDLS ranges from 0.21 to 2.82; it is low in the south and high in the north. The LCI ranges from 0.02 to 0.99; it is relatively low in those urban areas with a high building density. The LST ranges from 15.30 to 24.87 °C; in contrast to the spatial pattern of the LCI, the LST in the urban centers is higher than at the urban peripheries. The WRI ranges from 0.04 to 0.79; it is highest along the Yangtze and Jialing rivers. The FAI ranges from 0 to 1.63, exhibiting a gradual decline from the urban centers to the urban peripheries. As the FAI increases, the ventilation capacity worsens. 3) The ventilation-based human settlements index ranges from 0.06 to 0.54 in the mountainous areas of the city, gradually increasing from the southwest to the northeast in the main urban areas of Chongqing. In addition, zones with unsuitable human settlements are mainly distributed in mountainous regions with a high RDLS and relatively scarce water resources, whereas zones with suitable human settlements are primarily distributed in regions with a moderate RDLS, adequate vegetation cover, appropriate LST, abundant water resources, and adequate ventilation. The study findings can be used to evaluate the comfort level of human settlements, and have strategic significance to the efficient planning of urban development and the optimal layout of the population distribution.

Суточная и сезонная динамика температуры поверхности города Волгограда

Цель – установить особенности суточной и сезонной динамики температуры поверхности в городе Волгограде (на примере 2018 года, «типового» по климатическим характеристикам) и выяснить, зависит ли её сезонный ход от особенностей подстилающей поверхности городской территории. Материалы и методы. Для выбора года исследования был проанализирован 20-летний ход температур воздуха в Волгограде, а также учитывалось наличие непрерывных данных о температурах подстилающей поверхности. Определение температуры городской поверхности проводилось путем обработки снимков теплого полугодия информационного продукта MOD11A2 (8-ми дневные растровые композиты дневной и ночной температур разрешением около 1 км). Геоинформационная обработка снимков осуществлялась в программе QGIS. По данным Global Land Cover (GLC) определены основные типы подстилающей поверхности на территории Волгограда. Результаты и обсуждение. Доля запечатанных поверхностей составляет 38,2 %. Составлена карта среднегодовых температур поверхности в Волгограде, отражающая основные особенности пространственного распределения положительных и отрицательных тепловых аномалий. Установлено, что сезонный ход среднесуточных, дневных и ночных температур подстилающей поверхности и приземного слоя воздуха в Волгограде представляет собой обращенную ветвями вниз параболу с максимумом, приходящимся на период 26 июня – 6 июля. Ход среднесуточных температур воздуха повторяет сезонный ход температуры поверхности города (r = 0,99). Выводы. Картографирование на основе данных MODIS с разрешением 1 км позволяет выявить пространственное распространение крупных положительных и отрицательных аномалий на территории города и его окрестностей. Выявлена значительная вариабельность значений среднесуточной температуры подстилающей поверхности в районах с высокой долей водных объектов, водно-болотных угодий и низкой степенью запечатанности почвенного покрова.

Influence factor analysis of soil heavy metal Cd based on the GeoDetector

As a variant with high spatial differentiation and continuous space time, soil is polluted by various artificial or natural factors, and the pollution of heavy metal Cd is one of the more serious problems. This study took Liaocheng, as the research area and sampled the points in a grid center of 10 km × 10 km to obtain the sampling data of heavy metal Cd in the soil surface layer at depths of 0–20 cm. We selected the environmental background value of Shandong Province as the standard and used the geological accumulation index method to evaluate the pollution status of heavy metal Cd in the experimental area, concluding that there was a moderate level of Cd pollution in the study area. On this basis, we selected soil pH value, soil sub-class, annual average precipitation, annual average surface temperature, elevation data, and change in GDP as the six major influencing factors of heavy metal Cd in the study area by GeoDetector analysis. The correlation between soil heavy metal Cd and the impact factors was explored. The results revealed that soil pH and elevation exerted a large influence on soil Cd content, while annual average surface temperature had the least influence. The interaction of various influencing factors on heavy metal Cd was nonlinearly enhanced, especially the elevation data and annual average precipitation data.

Changes in the Dynamics of the Northern Hemisphere Atmospheric Circulation and the Relationship to Surface Temperature in the 20th and 21st Centuries

This study examines the long-term fluctuations in the Northern Hemisphere (NH) and global atmospheric circulation, teleconnections, including blocking, and surface temperature over the period 1899–2018. The teleconnection and blocking data were available from the mid-20th century. The classification of the global atmospheric circulation was developed from an early subjective categorization of atmospheric circulation conditions for the NH that considered the number, location, and amplitude of waves on the jet stream for frequently occurring circulation patterns. This work updated earlier studies that identified three circulation epochs based on the predominance of one of four different flow types that were grouped primarily based on whether the flow was zonal or meridional. This work noted a significant correlation between the early 21st century flow change toward the occurrence of more meridional flows and the increase in the occurrence of blocking as well as changes in the teleconnection indexes. The early 21st century was associated with a distinct change in the Northern Hemisphere flow entropy as measured using Information or Shannon Entropy, a change that was shown to be statistically significant. Additionally, this demonstrated that this quantity has utility as a dynamic diagnostic tool in atmospheric science. Finally, a comparison of these flow regimes to the 20th and 21st century variations in surface temperature were considered here. The global average annual surface temperature variations correlated strongly to fluctuations in the predominant atmospheric circulation type.

Analyis of periodical variability of insolation and soil temperature in the Crimea

According to the 22-year-old series of climatology NASA Surface meteorology and Solar Energy, the results of the analysis of the temporal series of local changes in insolation and the temperature of the earth and ground air in the Crimea are carried out. A statistical analysis was carried out and a continuous time-frequency wavelet analysis revealed increased (compared to other Crimean points) insolation and heating of the earth’s surface at Kara-Dag. Using the time-and-frequency continuous wavelet analysis, six regular astronomical fluctuations, the periods of which are comparable with the periods of seasonal fluctuations, lunar and lunar-solar tidal waves, were found in the spectral structure of data on the average daily insolation incident on the horizontal surface of the earth at Kara-Dag. Periodic oscillations comparable with fluctuations in solar activity and the dynamics of rotation of the Earth-Moon system are described by sinusoidal functions, the parameters of which are determined from observations. In the data on the average daily total insolation falling on the surface of the earth at the Kara-Dag point, regular periodic fluctuations were found over an interval of periods of ~(87―402) days. The most powerful harmonic oscillations are distinguished in the interval of periods ~(231―452) days; in the time interval ~(1995―2005) years, an increasing local increase in the vibrational energy is observed. An increase in the average annual average surface temperature in the Crimea in a southeastern direction has been recorded. In individual points, deviations from the general trend are observed, which may be associated with local geological processes. The greatest warming of the earth’s surface is observed at Kara-Dag, which corresponds to increased general insolation at this point. Using the method of calculating the functions of the mutual (two-channel) power spectral density, we established mutual correlations between the time sequences of observations of local changes in insolation and changes in the length of the day, the number of sunspots, and global temperature indices.

Standard normal homogeneity test as a tool to detect change points in climate-related river discharge variation: case study of the Kupa River Basin

ABSTRACTThe study addresses homogeneity testing of annual discharge time series for eight hydrological stations and five annual climate time series for one weather station in the Kupa River Basin, between Slovenia and Croatia, and global annual average surface temperature time series for the period 1961–2010. The standard normal homogeneity test (SNHT) was used to detect both abrupt and gradual linear trend homogeneity breaks. The results reveal natural change points at the beginning of the 1980s. Absolute homogeneity testing of average annual weather station-level air pressure, annual precipitation, differences between precipitation totals and potential evapotranspiration and surface runoff from the independent observation time series confirmed an abrupt shift, also at the beginning of the 1980s. The trend of local air temperature for 1985–2000, which partly coincides with global surface temperature trend for 1974–2005, strengthened the river discharge regime shift since the beginning of the 1980s. These results could improve climate variation monitoring and estimation of the impact of climate variation on the environment in the area. Generally, an indication of climate regime change points and an assessment of their duration could provide significant benefits for the society.

Effects of irrigation on water and energy balances in the Heihe River basin using VIC model under different irrigation scenarios

Investigations of the water and energy balance in large river basins is one of the most important and contemporary issues, which is helpful to guide agricultural production and regional water resource management. Traditionally, water and energy balance have been assessed by field-scale experiments. However, it is not easy to find the effective ways for a whole region using limited observed data from on-farm experiments. In our study, the effects of irrigation water on surface water and energy balance fluxes are examined by employing the Variable Infiltration Capacity (VIC) model and irrigation scheme, for the upper and middle reaches of the Heihe River Basin in Northwest China. The model simulations are calibrated and validated using both streamflow records at a gauge station and eddy covariance observations at two stations. Besides, three irrigation scenarios are set as full irrigation, 90% and 75% of irrigation water requirement (IWR). The results showed the infiltration curve parameter (b) and the thickness of lower soil moisture layer (d2) are the most sensitive model parameters. Long-term irrigation activities lead to a greater evapotranspiration (or latent heat). With considering local irrigation water-using coefficient for the period 2001–2010 of 0.527, the total IWR is about 2.81 × 109 m3/year (the net IWR is about 1.48 × 109 m3/year). Compared with the no-irrigation baseline, the increase in latent heat flux (about 4.45 W/m2) or the significant decrease in Bowen Ratio (about 1.05) due to full irrigation activities is accompanied by a decrease in annual average surface temperature (about 0.076 °C) for the middle reaches of the Heihe River basin during the 10-year period.

Climate Change and Implications for Prevention. California's Efforts to Provide Leadership.

The atmospheric concentration of carbon dioxide (CO2) and the temperature of the earth's surface have been rising in parallel for decades, with the former recently reaching 400 parts per million, consistent with a 1.5°C increase in global warming. Climate change models predict that a "business as usual" approach, that is, no effort to control CO2 emissions from combustion of fossil fuels, will result in a more than 2°C increase in annual average surface temperature by approximately 2034. With atmospheric warming comes increased air pollution. The concept of a "climate gap" in air quality control captures the decreased effectiveness of regulatory policies to reduce pollution with a hotter climate. Sources of greenhouse gases and climate-forcing aerosols ("black carbon") are the same sources of air pollutants that harm health. California has adopted robust climate change mitigation policies that are also designed to achieve public health cobenefits by improving air quality. These policies include advanced clean car standards, renewable energy, a sustainable communities strategy to limit suburban sprawl, a low carbon fuel standard, and energy efficiency. A market-based mechanism to put a price on CO2 emissions is the cap-and-trade program that allows capped facilities to trade state-issued greenhouse gas emissions allowances. The "cap" limits total greenhouse gas emissions from all covered sources, and declines over time to progressively reduce emissions. An alternative approach is a carbon tax. California's leadership on air quality and climate change mitigation is increasingly important, given the efforts to slow or even reverse implementation of such policies at the U.S. national level.

Impacts of climate change on water resources in the Huaihe River Basin

The Huaihe river basin, located in the transitional area of the humid zone to the semi arid zone, is a subtropical monsoon zone. By analysis of historical observation data, the annual average surface temperature increased by 0.5℃ over the past 50 years. However, the precipitation showed a fluctuation trend. Based on the hydrological and meteorological data of Huaihe River Basin, this paper studies impacts of climate change on water resources in Huaihe basin by using the Xinanjiang monthly hydrological model in conjunction with prediction products of NCAR climate model. The results show that the precipitation in the basin had a fluctuating upward trend under RCP8.5 and RCP4.5 scenarios, and the increase or decrease trend of precipitation in RCP2.6 scenario is not significant. The model predicted that the temperature of the river basin in the 3 scenarios shows significant rising trend from year 2001 to 2100. However, the annual runoff of the Huaihe River Basin shows an increasing trend but not significant from year 2001 to 2100.

A new modeling approach for improved ground temperature profile determination

The knowledge of the ground temperature profile with respect to time and depth is very important in many technological fields like geothermal heat pumps, solar energy systems and geotechnical applications. Many researches were performed in the past in order to evaluate this profile. The most common ones, known as energy balance models, use the energy balance equation as a boundary condition. Unfortunately the performance of these models strongly depends on an accurate estimation of several input factors. The objective of this paper is to develop an improved model for the prediction of the ground temperature profile in which the energy balance equation at the ground surface is supplemented by an empirical correlation for the annual average ground surface temperature calculation. This model is less sensitive to uncertainties of input factors. Furthermore, unlike the previous models, a periodic variation of the sky temperature is introduced instead of a previously assumed constant value. The model is validated against measured data in a site located in Varennes (Montreal-Canada) and two further sites, Fort Collins (Colorado) and Temple (Texas) in the U.S.A.