Annual Average Basis Research Articles

Epidemiological Trends and Outcomes of Unicompartmental Knee Arthroplasty Among 104 Million Patients in the United States

BackgroundUnicompartmental knee arthroplasty (UKA) is an alternative to total knee arthroplasty (TKA) for localized osteoarthritis. Recent advancements in UKA implant design and expanding patient criteria may have increased its utilization. However, few studies have examined the use of UKA in the United States. Thus, this study assessed the current and projected future trends of UKA and robotic UKA in the United States through 2035, along with postoperative outcomes. MethodsA collaborative healthcare research network was queried to identify patients who had undergone UKA. Primary outcomes measured included prevalence (P), incidence proportion (IP), and incidence rate (IR) from 2012 to 2022. Chi-squared analyses were done to compare outcomes across categorical data. Regression modeling was performed to project UKA to the year 2035. Statistical significance was held at P < .05 for all analyses. ResultsIn 2022, 1,662 UKAs were performed within the network, a 590% increase from 2012 (241 performed). The IP increased on an average annual basis by 41.8%, the IR by 50%, and the P by 51.3%. A year following UKA, conversion to TKA was the most common orthopaedic complication (39.9%). As of 2022, there were 68 robotic UKAs performed, a 518% increase from the 11 performed in 2012. Regression analysis for UKA through 2035 showed that IP will be 0.04%, IR will be 1.75 × 10−6 cases/person-day, and P will be 0.3%. ConclusionsThese findings are consistent with prior studies indicating a higher utilization of UKA over the past decade. Reported complications were not uncommon, as nearly 40% of patients required a conversion to a TKA. Further research is needed to optimally identify criteria for appropriate patients and determine the benefits robotic UKA may provide, specifically reducing the risk of conversion to a TKA.

Soil management practices can contribute to net carbon neutrality in California

Stabilizing climate requires reducing greenhouse gas (GHG) emissions and storing atmospheric carbon dioxide (CO2) in land or ocean systems. Soil management practices can reduce GHG emissions or sequester atmospheric CO2 into inorganic and organic forms. However, whether soil carbon strategies represent a viable and impactful climate mitigation pathway is uncertain. A specific question concerns the role that land-management practices and soil amendments can play in realizing California’s ambition for carbon neutrality by 2045. Here we examine the carbon flux impacts of soil conservation (i.e., compost, reduced tillage, cover crop) and enhanced silicate rock weathering (EW) practices at different areal extents of implementation in cropland, grassland, and savanna in California under two climate change cases. We show that with implementation areas of 15% or 50% of private cultivated land, grassland, and savanna in California, soil conservation practices alone can contribute 1.40.72.1 % ( −1.8−0.9−2.7 Mt CO2eq y−1) and 4.62.36.9 % ( −6.0−3.0−8.9 Mt CO2eq y−1) of the additional emissions reduction needed (beyond previous targets) to meet the 2045 net neutrality goal (−129.3 Mt CO2eq y−1), respectively, on an average annual basis, including climate uncertainty. Including EW in these scenarios increases the total contributions of management practices to 4.12.55.6 % ( −5.2−3.2−7.3 Mt CO2eq y−1) and 13.58.218.6 % ( −17.5−10.7−24.2 Mt CO2eq y−1), respectively, of this reduction. This highlights that the extent of implementation area is a major factor in determining benefits and that EW has the potential to make a real contribution to net reduction targets. Results are similar across climate cases, indicating that contemporary field data can be used to make future projections. With EW there remains mechanistic uncertainties, however, such as rock dissolution rate and environmental controls on weathering products, which require additional field research to improve understanding of the technological efficacy of this approach for California’s 2045 carbon neutrality goal.

Does China's pathway to carbon neutrality require the integration of land-based biological negative emission solutions with geochemical and chemical alternatives?

Carbon dioxide removal (CDR) is a necessary measure to achieve global climate targets. However, each CDR approach has potential trade-offs and spillover effects on the global energy-land-water system. To minimize these negative impacts and achieve climate targets, it has become increasingly important to assess different CDR deployment plans and how they interact with the Earth's system. The existing literature on CDR deployment in China is yet to uncover the potential synergies and trade-offs associated with varying CDR deployment strategies for the country's pathway to carbon neutrality. Here, we model five different CDR approaches categorized under four CDR deployment plans for China's climate aspirations using a variant of the Global Change Assessment Model, GCAM-CDR. Our goal here is not to definitively conclude the superiority of any specific CDR deployment plan for China's climate ambitions but instead to primarily explore and emphasize the potential implications associated with each group of CDR strategies. We show that China's pursuit of carbon neutrality solely through land-based biological CDR methods could result in reduced fossil fuel consumption, greenhouse gas emissions, and total air pollutants. However, an integrated approach that combines both land-based biological and geo/chemical CDR strategies could enhance the economic feasibility of achieving China's climate objectives. Moreover, it could reduce land and water requirements for energy generation and negative emissions, thereby mitigating the pressure on food croplands and other sustainability issues. Compared with an integrated approach, relying solely on land-based biological CDR processes for China's carbon neutrality goal could lead to a cumulative reduction in residual GHG emissions by at least 2 GtCO2e over the next four decades (in 5-year intervals) as China progresses towards carbon neutrality. On the other hand, the mitigation cost of relying exclusively on land-based biological CDR processes for China's carbon neutrality goals could be approximately 30 % higher than that of an integrated approach (on an annual average basis). In conclusion, China's policymakers and stakeholders should carefully assess different combinations of diverse CDR approaches, considering the associated impacts on the country's energy-land-water system and policy costs, to make informed decisions that help maximize benefits and minimize negative consequences in pursuit of carbon neutrality goals.

LOSSES OF HUMAN CAPITAL IN THE REGIONS OF UKRAINE DURING THE PERIOD OF RUSSIAN MILITARY AGGRESSION

The purpose of the work is to study the loss of human capital in Ukraine and its regions during the latest Russian-Ukrainian war, which began in 2014. The study of the loss of human capital in Ukraine and its regions during the period of Russian military aggression was carried out in three stages. At the first stage, direct losses of this capital during 2014-2021 were calculated. The second and third stages of this study are devoted to the study of indirect losses of this capital, respectively, for the same period and the period after the full-scale invasion of Russian troops on February 24, 2022. The conducted studies showed that during the Russian military aggression, the human capital of Ukraine suffered significant losses. The calculation of direct losses of this capital showed that these losses for the period of 2014-2021 amounted to 1994,55 thousand people on an average annual basis. The largest direct losses of the HC of Ukraine were experienced in the Donetsk, Dnipropetrovsk, Kharkiv and Zaporizhzhia regions, and the smallest – in the Chernivtsi, Kyiv, Volyn and Ivano-Frankivsk regions. Studies of indirect losses of human capital before and after a full-scale invasion by the Russians also indicate their significant volumes. The largest volumes of indirect losses of human capital were observed after the full-scale Russian invasion of the country on February 24, 2022. According to the number of damaged, destroyed and destroyed educational, cultural and health care institutions in the regions of Ukraine after that date, the greatest losses of human capital were incurred in the Donetsk, Kyiv, Luhansk, Mykolaiv, Kharkiv, Kherson and Chernihiv regions.

Demographic, Healthcare Access, and Dietary Factors Associated With Thyroid Hormone Treatments for Hypothyroidism.

Clinical guidelines have recommended a trial of liothyronine (LT3) with levothyroxine (LT4) in select patients with hypothyroidism. However, little is known about the real-world use of LT3 and desiccated thyroid extract (DTE) and the characteristics of patients treated with LT3 and DTE. (1) Determine national trends of new LT4, LT3, and DTE prescriptions in the United States; (2) determine whether sociodemographic, healthcare access, and dietary factors are associated with different thyroid hormone (TH) therapies. Parallel cross-sectional studies were conducted using 2 datasets: (1) a national patient claims dataset (2010-2020) and (2) the National Health and Nutrition Examination Study (NHANES) dataset (1999-2016). Included participants had a diagnosis of primary or subclinical hypothyroidism. Study outcomes included the impact of demographics and healthcare access on differences in the proportion of TH therapies consisting of LT4, LT3, and DTE (patient claims) and differences in dietary behaviors between DTE-treated participants and LT4-treated matched controls (NHANES). On an average annual basis, 47 711 adults received at least 1 new TH prescription, with 88.3% receiving LT4 monotherapy, 2.0% receiving LT3 therapy, and 9.4% receiving DTE therapy. The proportion receiving DTE therapy increased from 5.4% in 2010 to 10.2% in 2020. In the analysis between states, high primary care and endocrinology physician densities were associated with increased use of LT4 monotherapy (odds ratio 2.51, P < .001 and odds ratio 2.71, P < .001). DTE-treated NHANES participants (n = 73) consumed more dietary supplements compared to LT4-treated participants (n = 146) (4.7 vs 2.1, P < .001). The proportion of new TH therapies containing DTE for hypothyroidism doubled since 2010 while LT3 therapies remained stable. DTE treatment was associated with decreased physician density and increased dietary supplement use.

Innovative solar natural vacuum desalination system

The main target of the work is a design of an innovative solar natural vacuum desalination (SNVD) system and improve performance of such systems. The natural vacuum is developed by raising up an evaporation chamber to 9.8 m above the ground. The waste heat is efficiently utilized in that system to minimize the system heat loss. The fresh water is first preheated by condensing vapor from the evaporation chamber before it is heated by a flat-plate collector as a heat source of the evaporation chamber. On the other side, the sea water is preheated by the produced warm water, and it is reheated by the exit brine water before it is supplied into the evaporation chamber. A mathematical model and a transient simulation were established to investigate the annual performance of system. A heat balance of each system component was provided to estimate the inlet and outlet temperature and flow rate of it. Moreover, the collector area was estimated based on assumed mass flow rates of both feed sea water and coolant water. It was found that the system can produce a daily production of 6.2 L of pure water per a quadratic meter of collector on annual average basis. That Productivity can be estimated as 1.12 L of water per kWh solar radiation. Accordingly, the evaporation rate was estimated as 2.82% while the gain output ratio (GOR) was obtained as 0.63. The system performance can be accepted compared with the corresponding published systems.

Hydroclimate Impact Analyses and Water Management in the Central Rift Valley Basin in Ethiopia

This study explores the impacts of climate change on the major components of the water balance such as surface runoff (Q), water yield (WY), and evapotranspiration (ET) in the Central Rift Valley Basin (CRVB) in Ethiopia. Projected climate data from the climate emission scenarios were used for the analyses. Representative concentration pathway (RCP) data from the MIROC-RCA4 ensemble driving climate models were downscaled, bias-corrected, and applied for impact analyses. Climate scenario analyses for the near-term (2031–2060) and long-term (2070–2099) periods were used to assess the conditions of the water balance components. The endo hydrogenic CRVB was divided into three sub-basins, and their respective hydroclimatic impacts were simulated separately with calibrated Arc-SWAT models. The future impacts simulated on the annual average basis vary in their maximum ranges from −65.2% to +85.8% in Q, from −42.2% to +23.9% in WY, and from −4.1% to +17.3% in ET compared to the baseline data outputs in the individual sub-basin. Water management options according to the water balance sensitivities to the climate impacts were proposed for each of the sub-basins. SWAT-based studies aimed at balanced water resources management in combination with agricultural practices within the CRVB are recommended for future research.

Economic Evaluation of Ecological Restoration of Degraded Lands through Protective Afforestation in the South of the Russian Plain

The latest international climate documents emphasize the great importance of protective forest stands in ensuring the sustainable development of agriculture, and the main requirement is the use of the forest-forming factor by landowners in the interests of improving the environment. In Russia, until recently, the ecological significance of forest plantations was underestimated, which created the ground for discussions about their effectiveness. In this regard, a new approach is proposed that emphasizes the positive impact of forests, including sustainable development, environmental security of the agricultural sector and reducing the degradation of agricultural land. The purpose of the work was an economic assessment and regularities of the dynamics of humus-regulating and nitrogen-phosphorus-potassium (NPK)-regulating efficiency of protective forest plantations on lands with deflation-hazardous soils. By means of a system analysis, the change in the soil cover of land use due to the influence of forest plantations on the balance of soil fertility elements in forested cells is comprehensively analyzed. The different spatial placement of trees from each other under different degrees of deflation in semiarid conditions is modeled. These models are used to determine the nature of the dynamics of soil nutrients in forested areas: in protection zones and outside protection. It is established that the anti-deflationary effect of agroforestry depends on the indicator of the protective forest cover of the land, the level of deflationary danger, and the operational life of the plantings. In semiarid conditions, it increases in proportion to the increase in the protection of land and amounts to EUR 376–EUR 4222 ha−1. With an increase in the intensity of deflation to the level of dust storms, the prevented damage from the loss of soil nutrients increases almost four times. In systems of plantings from early-maturing fast-growing rocks, the anti-deflationary effect is 6–7% higher on an average annual basis than in systems of plantings from long-lasting, slow-growing rocks. The greatest efficiency of forest reclamation in ensuring a positive balance of humus and NPK substances in the soil (EUR 1002–EUR 4222 ha−1) is achieved when placing plantings after 15 H. The study will confirm the need to subsidize the integration of trees into farm systems.

Reduced sediment export to the Pennsylvania Lake Erie littoral zone during an era of average lake levels

This paper analyzes high-resolution lidar data to estimate sediment export to the Pennsylvania Lake Erie littoral zone from lakefront bluff retreat under relatively unique lake-level conditions: approximately a decade of average lake level transitioning into a mild transgression. Analysis identifies bluff-failure patterns important to coastal hazard planning, possible feeder-bluff conservation areas to preserve sediment supply, and data pertinent to sand management in the western Erie County littoral cell (WECLC) and at Presque Isle State Park in the next-downdrift cell.Based on 2007–2015 bluff-face mapping, there were net losses of 318,250 m3 of total-sediment and 105,700 m3 of sand+ (sand-boulders) to the littoral zone. On an average annual basis, bluffs thus exported 39,800 m3 of total-sediment and 13,300 m3 of sand+ to the WECLC. Exports of sand+ by six HUC-12 watersheds ranged from ~0 to 4600 m3/yr, with ~ 30% supplied by Crooked Creek watershed bluffs that occupy only 18% of the coast. Sand+ export volumes reported here were ~65% lower than prior research covering different lake-level phases. Understanding sediment export during periods of average lake level is important because such lake-level phases occur in the record and will likely recur. Incorporating a decade-scale low sediment-supply scenario for sand management in the Presque Isle littoral cell would permit fine-tuning of estimates of sand nourishment needed to mitigate ongoing beach erosion. Uncertainty in bluff-face change can be minimized by expanding data-comparison windows; future tracking of sediment export from Pennsylvania bluffs may not need lidar surveys any more frequently than once every 10–15 years.

Evaluation of uncertainties derived from meteorological forecast inputs in plume directions predicted by atmospheric dispersion simulations

ABSTRACT Atmospheric transport, dispersion, and deposition models (ATDMs) can support decision-making during nuclear emergencies; however, uncertainties in the ATDM results need to be carefully evaluated. To investigate the uncertainties derived from meteorological forecast inputs, we conducted three-day forecast simulations every day for one year with hypothetical releases of radionuclides (one-hour releases every 6 h) from a nuclear facility. The forecast outputs were compared with the analysis outputs during the same period. The difference between the outputs is treated as the uncertainty in the forecasts and is represented as an angle based on the discrepancy in the plume directions between the analysis and forecast outputs. Using meteorological inputs made by Japan Meteorological Agency, the discrepancy angle (Ang) increased by approximately 10 per day on an annual average basis. Meanwhile, the Ang values were occasionally 4–5 times higher than the annual average during short time periods. Since the Ang time series show seasonal and diurnal changes, the statistical characteristics likely depend on the geographical and meteorological conditions, as well as the types of meteorological inputs. Additionally, a main factor in the uncertainty is the wind-direction difference between the analysis and forecast outputs on scales of more than or less than 100 km.

Temporal variations of de facto wastewater reuse and disinfection by-products in public water systems in the Shenandoah River watershed, USA

Abstract Temporal variations of de facto wastewater reuse are relevant to public drinking water systems (PWSs) that obtain water from surface sources. Variations in wastewater discharge flows, streamflow, de facto reuse, and disinfection by-products (DBPs – trihalomethane-4 [THM4] and haloacetic acid-5 [HAA5]) over an 18-year period were examined at 11 PWSs in the Shenandoah River watershed, using more than 25,000 data records, in gaged and ungaged reaches. The relationship of de facto reuse with DBPs by year and quarter at the PWSs was examined. A linear relationship was found between THM4 and de facto reuse on an annual average basis (p = 0.050), as well as in quarters 3 (July – September) (p = 0.032) and 4 (October – December) (p = 0.031). Using a t-test (p &amp;lt; 0.05), the study also showed that there were significant differences in DBP levels for PWSs relative to 1% de facto reuse. This was found for THM4 based on annual average and quarter 1 (January – March) data, and for HAA5 based on quarter 3 data during the period of record.

Assessing the Effect of Changing Ambient Air Temperature on Water Temperature and Quality in Drinking Water Distribution Systems

Drinking water distribution systems (DWDS) are affected by climate change and this work aimed to assess the effect of changing ambient air temperature on the water temperature and various water quality parameters in DWDS. A water temperature estimation model was identified and evaluated at seven specific locations in the U.S. and water quality parameters were assessed with a case study for Washington D.C. Preliminary estimation of changes in water temperature and two temperature-related parameters (the chlorine decay rate and bacterial activity) were developed for 91 U.S. cities using local air temperature observations and projections. Estimated water temperature changes in DWDS are generally equivalent to air temperature changes on an annual average basis, suggesting modest changes for the assessed historical periods and possibly more intensified changes in the future with greater increase in air temperature. As higher water age can amplify the temperature effect and the effects of temperature on some water quality parameters can be inter-related, yielding an aggregated effect, evaluation of extreme cases for DWDS will be of importance. In responding to changing climate conditions, assessments of DWDS water temperature changes and resulting impacts on water quality merit more attention to ensure appropriate adaptation of DWDS design and management.

NpTrack: A n-Position Single Axis Solar Tracker Model for Optimized Energy Collection

The single axis solar tracker based on flat panels is used in large solar plants and in distribution-level photovoltaic systems. In order to achieve this, the solar tracking systems generally need to work by tracking the sun’s position with dozens, maybe hundreds of movements along the day with a maximal known tracking error within the specifications. A novel model is proposed along this work based on the control of the angle deviation within a (polar) single axis configuration. This way an optimization of the harnessing of solar energy can be achieved with as few panel displacements as possible in order to decrease the wear in the mechanical parts of the equipment and the energy consumed by it. This tracking approach was implemented with as few as seven positions along the day and got an estimated theoretical value of 99.27% of the total collected energy in a continuous tracking system. Regarding an annual average basis, it would be about 96.5% of a dual axis system according to the proposed model. The novelty of the model is related to a tradeoff between the gain with the simplicity of a single axis n-position tracking and the solar energy loss associated.

The increasing atmospheric burden of the greenhouse gas sulfur hexafluoride (SF&amp;lt;sub&amp;gt;6&amp;lt;/sub&amp;gt;)

Abstract. We report a 40-year history of SF6 atmospheric mole fractions measured at the Advanced Global Atmospheric Gases Experiment (AGAGE) monitoring sites, combined with archived air samples, to determine emission estimates from 1978 to 2018. Previously we reported a global emission rate of 7.3±0.6 Gg yr−1 in 2008 and over the past decade emissions have continued to increase by about 24 % to 9.04±0.35 Gg yr−1 in 2018. We show that changing patterns in SF6 consumption from developed (Kyoto Protocol Annex-1) to developing countries (non-Annex-1) and the rapid global expansion of the electric power industry, mainly in Asia, have increased the demand for SF6-insulated switchgear, circuit breakers, and transformers. The large bank of SF6 sequestered in this electrical equipment provides a substantial source of emissions from maintenance, replacement, and continuous leakage. Other emissive sources of SF6 occur from the magnesium, aluminium, and electronics industries as well as more minor industrial applications. More recently, reported emissions, including those from electrical equipment and metal industries, primarily in the Annex-1 countries, have declined steadily through substitution of alternative blanketing gases and technological improvements in less emissive equipment and more efficient industrial practices. Nevertheless, there are still demands for SF6 in Annex-1 countries due to economic growth, as well as continuing emissions from older equipment and additional emissions from newly installed SF6-insulated electrical equipment, although at low emission rates. In addition, in the non-Annex-1 countries, SF6 emissions have increased due to an expansion in the growth of the electrical power, metal, and electronics industries to support their continuing development. There is an annual difference of 2.5–5 Gg yr−1 (1990–2018) between our modelled top-down emissions and the UNFCCC-reported bottom-up emissions (United Nations Framework Convention on Climate Change), which we attempt to reconcile through analysis of the potential contribution of emissions from the various industrial applications which use SF6. We also investigate regional emissions in East Asia (China, S. Korea) and western Europe and their respective contributions to the global atmospheric SF6 inventory. On an average annual basis, our estimated emissions from the whole of China are approximately 10 times greater than emissions from western Europe. In 2018, our modelled Chinese and western European emissions accounted for ∼36 % and 3.1 %, respectively, of our global SF6 emissions estimate.

Comparative analysis of water budgets across the U.S. long-term agroecosystem research network

Understanding the movement and storage of water within agricultural landscapes as functions of management and climate is essential for more efficient and sustainable water use. However, knowledge of water storage and fluxes on U.S. agricultural lands is largely incomplete. The Long-Term Agroecosystem Research (LTAR) network provides a unique and geographically diverse set of agricultural study sites in the United States. The objectives of this study were to: 1) characterize the hydrologic variability across the LTAR network; 2) identify data gaps in the water budgets across the LTAR network; and 3) identify opportunities to leverage the LTAR network to improve understanding of water budgets across agricultural landscapes. For each of the 18 LTAR sites, we developed water budgets on an average annual basis. Uncertainty propagation methods combined individual component uncertainties to calculate an overall water budget uncertainty. Datasets length ranged from three to 50 years. The network covers a range of precipitation from 240 to 1400 mm yr−1, evapotranspiration from 228 to 1080 mm yr−1, and surface runoff and subsurface flow from negligible to 560 mm yr−1. However, uncertainties of where all the water is going remained high, in part because soil water storage and downward movement of water were often neglected or measured for very short periods, resulting in average water budget uncertainty of 25% of the water inputs. More accurate measurement of the major inputs and outputs, and direct measurement of water content and percolation are key to understanding how agricultural lands affect terrestrial water budgets.

Reduction in Ocean Heat Transport at 26°N since 2008 Cools the Eastern Subpolar Gyre of the North Atlantic Ocean

AbstractNorthward ocean heat transport at 26°N in the Atlantic Ocean has been measured since 2004. The ocean heat transport is large—approximately 1.25 PW, and on interannual time scales it exhibits surprisingly large temporal variability. There has been a long-term reduction in ocean heat transport of 0.17 PW from 1.32 PW before 2009 to 1.15 PW after 2009 (2009–16) on an annual average basis associated with a 2.5-Sv (1 Sv ≡ 106 m3 s−1) drop in the Atlantic meridional overturning circulation (AMOC). The reduction in the AMOC has cooled and freshened the upper ocean north of 26°N over an area following the offshore edge of the Gulf Stream/North Atlantic Current from the Bahamas to Iceland. Cooling peaks south of Iceland where surface temperatures are as much as 2°C cooler in 2016 than they were in 2008. Heat uptake by the atmosphere appears to have been affected particularly along the path of the North Atlantic Current. For the reduction in ocean heat transport, changes in ocean heat content account for about one-quarter of the long-term reduction in ocean heat transport while reduced heat uptake by the atmosphere appears to account for the remainder of the change in ocean heat transport.

Molecular characterization of organic aerosols in the Kathmandu Valley, Nepal: insights into primary and secondary sources

Abstract. Organic atmospheric aerosols in the Hindu Kush–Himalayas–Tibetan Plateau region are still poorly characterized. To better understand the chemical characteristics and sources of organic aerosols in the foothill region of the central Himalaya, the atmospheric aerosol samples were collected in Bode, a suburban site of the Kathmandu Valley (KV) over a 1-year period from April 2013 to April 2014. Various molecular tracers from specific sources of primary organic aerosols (POAs) and secondary organic aerosols (SOAs) were determined. Tracer-based estimation methods were employed to apportion contributions from each source. The concentrations of organic carbon (OC) and elemental carbon (EC) increased during winter with a maximum monthly average in January. Levoglucosan (a molecular tracer for biomass burning, BB) was observed as the dominant species among all the analyzed organic tracers and its annual average concentration was 788±685 ng m−3 (ranging from 58.8 to 3079 ng m−3). Isoprene-SOA (I-SOA) represented a high concentration among biogenic-SOA tracers. For the seasonality, anhydrosugars, phenolic compounds, resin acid, and aromatic SOA tracer showed similar seasonal variations with OC and EC while monosaccharides, sugar alcohols, and I-SOA tracers showed lower levels during winter. BB contributed a significant fraction to OC, averaging 24.9 %±10.4 % during the whole year, and up to 36.3 %±10.4 % in the post-monsoon season. On an annual average basis, anthropogenic toluene-derived secondary OC accounted for 8.8 % and biogenic secondary OC contributed 6.2 % to total OC. The annual contribution of fungal spores to OC was 3.2 % with a maximum during the monsoon season (5.9 %). For plant debris, it accounted for 1.4 % of OC during the monsoon. Therefore, OC is mainly associated with BB and other anthropogenic activity in the KV. Our findings are conducive to designing effective measures to mitigate the heavy air pollution and its impacts in the KV and surrounding area.

Reconciling Canopy Interception Parameterization and Rainfall Forcing Frequency in the Community Land Model for Simulating Evapotranspiration of Rainforests and Oil Palm Plantations in Indonesia

AbstractBy mediating evapotranspiration processes, plant canopies play an important role in the terrestrial water cycle and regional climate. Substantial uncertainties exist in modeling canopy water interception and related hydrological processes due to rainfall forcing frequency selection and varying canopy traits. Here we design a new time interpolation method “zero” to better represent convective‐type precipitation in tropical regions. We also implement and recalibrate plant functional type‐specific interception parameters for rainforests and oil palm plantations, where oil palms express higher water interception capacity than forests, using the Community Land Model (CLM) versions 4.5 and 5.0 with CLM‐Palm embedded. Reconciling the interception scheme with realistic precipitation forcing produces more accurate canopy evaporation and transpiration for both plant functional types, which in turn improves simulated evapotranspiration and energy partitioning when benchmarked against observations from our study sites in Indonesia and an extensive literature review. Regional simulations for Sumatra and Kalimantan show that industrial oil palm plantations have 18–27% higher transpiration and 15–20% higher evapotranspiration than forests on an annual regional average basis across different ages or successional stages, even though the forests experience higher average precipitation according to reanalysis data. Our land‐only modeling results indicate that current oil palm plantations in Sumatra and Kalimantan use 15–20% more water (mean 220 mm or 20 Gt) per year compared to lowland rainforests of the same extent. The extra water use by oil palm reduces soil moisture and runoff that could affect ecosystem services such as productivity of staple crops and availability of drinking water in rural areas.

Smart Appliances for Efficient Integration of Solar Energy: A Dutch Case Study of a Residential Smart Grid Pilot

This paper analyzes the use patterns of a residential smart grid pilot in the Netherlands, called PowerMatching City. The analysis is based on detailed monitoring data measured at 5-min intervals for the year 2012, originating from this pilot which was realized in 2007 in Groningen, Netherlands. In this pilot, smart appliances, heat pumps, micro-combined heat and power (µ-CHP), and solar photovoltaic (PV) systems have been installed to evaluate their efficiency, their ability to reduce peak electricity purchase, and their effects on self-sufficiency and on the local use of solar electricity. As a result of the evaluation, diverse yearly and weekly indicators have been determined, such as electricity purchase and delivery, solar production, flexible generation, and load. Depending on the household configuration, up to 40% of self-sufficiency is achieved on an annual average basis, and 14.4% of the total consumption were flexible. In general, we can conclude that micro-CHP contributed to keep purchase from the grid relatively constant throughout the seasons. Adding to that, smart appliances significantly contributed to load shifting in peak times. It is recommended that similar evaluations will be conducted in other smart grid pilots to statistically enhance insights in the functioning of residential smart grids.

Geochemical characterization and evolution of the groundwater along the flow path, Gharandal watershed, South Sinai, Egypt

Gharandal watershed (882 Km2) is part of South Sinai, which represent a remote arid area. Groundwater of the Quaternary aquifer, represents the only water resources for drinking, irrigation and domestic use in this watershed. An integrated approach was used to identifying the geochemical processes controlling the groundwater quality and characterize their evolution along the flow path, depending on the hydrogeochemical and isotopic data. The stable isotopes (δ18O and δ2H) data elucidate that the studied aquifer is ensured by recent recharge from the local rains. The hydrogeochemical results outline that evaporation, rock-water interaction (particularly dissolution of carbonates and evaporates minerals in aquifer matrix) and the cation exchange, are the main geochemical processes accountable for increasing salinity and the evolution of the groundwater along the flow path. The hydroeochemical facies evolves from Mg-Na-SO4-HCO3 at recharge area into Ca-Na-SO4-Cl at the middle parts of the main channel and finally Na-Ca-Cl-SO4 in the downstream of the studied watershed. Geochemical modeling (NETPATH) indicating upgrading in the Quaternary aquifer water from the upstream to produce groundwater at downstream portion. The current study recommended that the Quaternary aquifer should be managed in a sustainable way by not pumping more than the recharged on an average annual basis.