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It's not only the carbon in the trees Forest loss affects climate not just because of the impacts it has on the carbon cycle, but also because of how it affects the fluxes of energy and water between the land and the atmosphere. Evaluating global impact is complicated because deforestation can produce different results in different climate zones, making it hard to determine large-scale trends rather than more local ones. Alkama and Cescatti conducted a global assessment of the biophysical effects of forest cover change. Forest loss amplifies diurnal temperature variations, increases mean and maximum air temperatures, and causes a significant amount of warming when compared to CO 2 emission from land-use change. Science , this issue p. 600

Global Warming: A Study of the Gaza Temperature Variations in the Period 1976-1995

Reservoirs in Taiwan often provide hydroelectric power, irrigation water, municipal water, and flood control for the whole year. Taiwan has the climatic characteristics of concentrated rainy seasons, instantaneous heavy rains due to typhoons and rainy seasons. In addition, steep rivers in mountainous areas flow fast and furiously. Under such circumstances, reservoirs have to face sudden heavy rainfall and surges in water levels within a short period of time, which often causes the water level to continue to rise to the full level even though hydroelectric units are operating at full capacity, and as reservoirs can only drain the flood water, this results in the waste of hydropower resources. In recent years, the impact of climate change has caused extreme weather events to occur more frequently, increasing the need for flood control, and the reservoir operation has faced severe challenges in order to fulfil its multipurpose requirements. Therefore, in order to avoid the waste of hydropower resources and improve the effectiveness of the reservoir operation, this paper proposes a real-time 48-h ahead water level forecasting system, based on fuzzy neural networks with multi-stage architecture. The proposed multi-stage architecture provides reservoir inflow estimation, 48-h ahead reservoir inflow forecasting, and 48-h ahead water level forecasting. The proposed method has been implemented at the Techi hydropower plant in Taiwan. Experimental results show that the proposed method can effectively increase energy efficiency and allow the reservoir water resources to be fully utilized. In addition, the proposed method can improve the effectiveness of the hydropower plant, especially when rain is heavy.

The study evaluated the effect of environmental conditions and morphometric parameters on lake water temperature changes. The analysis was carried out on the basis of 14 lakes located in northern Poland. The assessment was based on the daily water and air temperatures from 1972 to 2016. It took into account the location of lakes (latitude, longitude, altitude) morphometric parameters (surface area, maximum and mean depth, volume), hydrological processes (rate of water exchange, course of ice phenomena), and trophic status (water transparency) as factors that can modify lake water temperature changes. Direction and rate of air and water temperature changes were analysed by means of Mann–Kendall’s and Sen’s tests. Cluster analysis (CA) was applied to group lakes characterised by similar water temperature changes. The effect of climatic and non-climatic parameters on a lake’s water temperature was assessed on the basis of principal component analysis (PCA). Water temperatures in the lakes in the years 1972–2016 were characterised by a higher rate of increase of 0.43 °C·dec−1 than the air temperature decrease of 0.34 °C·dec−1. The analysis showed a faster rate of heating of waters in western Poland. This can be explained by shorter duration of ice cover. Moreover, the changes of water temperature were affected by other factors, including the location of the lakes, their morphometric parameters, wind speed, water transparency and water exchange time.

AbstractThe change in the phenology of plants or animals reflects the response of living systems to climate change. Numerous studies have reported a consistent earlier spring phenophases in many parts of middle and high latitudes reflecting increasing temperatures with the exception of China. A systematic analysis of Chinese phenological response could complement the assessment of climate change impact for the whole Northern Hemisphere. Here, we analyze 1263 phenological time series (1960–2011, with 20+ years data) of 112 species extracted from 48 studies across 145 sites in China. Taxonomic groups include trees, shrubs, herbs, birds, amphibians and insects. Results demonstrate that 90.8% of the spring/summer phenophases time series show earlier trends and 69.0% of the autumn phenophases records show later trends. For spring/summer phenophases, the mean advance across all the taxonomic groups was 2.75 days decade−1 ranging between 2.11 and 6.11 days decade−1 for insects and amphibians, respectively. Herbs and amphibians show significantly stronger advancement than trees, shrubs and insect. The response of phenophases of different taxonomic groups in autumn is more complex: trees, shrubs, herbs and insects show a delay between 1.93 and 4.84 days decade−1, while other groups reveal an advancement ranging from 1.10 to 2.11 days decade−1. For woody plants (including trees and shrubs), the stronger shifts toward earlier spring/summer were detected from the data series starting from more recent decades (1980s–2000s). The geographic factors (latitude, longitude and altitude) could only explain 9% and 3% of the overall variance in spring/summer and autumn phenological trends, respectively. The rate of change in spring/summer phenophase of woody plants (1960s–2000s) generally matches measured local warming across 49 sites in China (R = −0.33, P < 0.05).

This short communication discussed the water-energy-environment-economy nexus, and the challenges and opportunities progressing towards net zero. A circular water economy is an approach to water management that seeks to maximize the use and reuse of water resources, reduce waste and pollution, and promote sustainable and equitable access to water for all, where desalination may play an important role. The transition towards net zero, moving from an energy system based on fossil fuels not sustainable anymore to a renewable energy system, may impact the cost and availability of energy. Desalination definitively needs cheap and abundant energy, and investments which also depend on the accessibility of inexpensive and plentiful energy. Expensive and scarce energy may impact negatively on desalination, and contribute to water scarcity.

This paper presents a data model for organizing the inputs and outputs of an energy balance snowmelt model (the Utah Energy Balance Model, UEB) that provides a foundation for its integration into the EPA BASINS modeling framework and enables its coupling with other hydrologic models in this system. Having UEB as a BASINS component has facilitated its coupling with the Geospatial Streamflow Forecast Model (GeoSFM) to compute the melting of glaciers and subsequent streamflow in the Himalayas. The data model uses a combination of structured text and network Common Data Form (netCDF) files to represent parameters, geographical, time series, and gridded space-time data. We describe the design and structure of this data model, integration methodology of UEB and GeoSFM and illustrate the effectiveness of the resulting coupled models for the computation of surface water input and streamflow for a glaciated watershed in Nepal Himalayas. We developed a data model to structure the input and output of an energy balance snow and glacier melt model.A rainfall-runoff model was coupled with a snow and glacier melt model in EPA BASINS to enhance streamflow information.The model was applied to simulate streamflow using snow and glacier melt information in a high altitude Himalayan watershed.

Abstract Sultan Marshes is one of Turkey's Ramsar wetlands and has faced significant threats in recent years. Although the water was brought from other basins for restoration, observed temporal human-induced impacts and the current drought have damaged the wetland qualities of the Marshes. In this study, the temporal change of the Marshes and the human-induced effects are analyzed. Spatiotemporal surface water area (1984-2020) and whole land use changes (1990-2018) are evaluated with the temporal change of the Human Development, Global Terrestrial Human Footprint, and Ecological Footprint Indexes. The land use changes since 1990 reveal how the wetland has lost its functions. Especially between 1990-2000, the water area largely shifted into the sandy and swampy areas. In the swampy areas between 1990-2000, natural pasture formation was also observed in 2000. In addition, it is found that mining fields were constructed in the region between 1990-2000, albeit relatively small. According to the study, the most remarkable change occurred in the 1990-2000 period, considering the entire study timeline (1990-2018). In this period, there was also a transformation into irrigated agricultural lands around the national park. Moreover, there was a transformation from orchards and pasture areas to irrigated agricultural areas. When the changes in the wetland are evaluated with the human footprint data for 1993 and 2009, it was found that human impact was more substantial, especially in 1993 compared to 2009. This is in line with the continuous increase in HDI values between 1990 (0.54) and 2018 (0.81). Besides, the ecological footprint has increased since 1983. After 1983, the biocapacity in the region has steadily decreased to negative values.