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1.
Sci Data ; 10(1): 374, 2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37291162

RESUMEN

With the urgent need to implement the EU countries pledges and to monitor the effectiveness of Green Deal plan, Monitoring Reporting and Verification tools are needed to track how emissions are changing for all the sectors. Current official inventories only provide annual estimates of national CO2 emissions with a lag of 1+ year which do not capture the variations of emissions due to recent shocks including COVID lockdowns and economic rebounds, war in Ukraine. Here we present a near-real-time country-level dataset of daily fossil fuel and cement emissions from January 2019 through December 2021 for 27 EU countries and UK, which called Carbon Monitor Europe. The data are calculated separately for six sectors: power, industry, ground transportation, domestic aviation, international aviation and residential. Daily CO2 emissions are estimated from a large set of activity data compiled from different sources. The goal of this dataset is to improve the timeliness and temporal resolution of emissions for European countries, to inform the public and decision makers about current emissions changes in Europe.

2.
Sci Data ; 10(1): 217, 2023 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-37069166

RESUMEN

We constructed a frequently updated, near-real-time global power generation dataset: CarbonMonitor-Power since January, 2016 at national levels with near-global coverage and hourly-to-daily time resolution. The data presented here are collected from 37 countries across all continents for eight source groups, including three types of fossil sources (coal, gas, and oil), nuclear energy and four groups of renewable energy sources (solar energy, wind energy, hydro energy and other renewables including biomass, geothermal, etc.). The global near-real-time power dataset shows the dynamics of the global power system, including its hourly, daily, weekly and seasonal patterns as influenced by daily periodical activities, weekends, seasonal cycles, regular and irregular events (i.e., holidays) and extreme events (i.e., the COVID-19 pandemic). The CarbonMonitor-Power dataset reveals that the COVID-19 pandemic caused strong disruptions in some countries (i.e., China and India), leading to a temporary or long-lasting shift to low carbon intensity, while it had only little impact in some other countries (i.e., Australia). This dataset offers a large range of opportunities for power-related scientific research and policy-making.

3.
Sci Data ; 10(1): 69, 2023 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-36732516

RESUMEN

We present a near-real-time global gridded daily CO2 emissions dataset (GRACED) throughout 2021. GRACED provides gridded CO2 emissions at a 0.1° × 0.1° spatial resolution and 1-day temporal resolution from cement production and fossil fuel combustion over seven sectors, including industry, power, residential consumption, ground transportation, international aviation, domestic aviation, and international shipping. GRACED is prepared from the near-real-time daily national CO2 emissions estimates (Carbon Monitor), multi-source spatial activity data emissions and satellite NO2 data for time variations of those spatial activity data. GRACED provides the most timely overview of emissions distribution changes, which enables more accurate and timely identification of when and where fossil CO2 emissions have rebounded and decreased. Uncertainty analysis of GRACED gives a grid-level two-sigma uncertainty of value of ±19.9% in 2021, indicating the reliability of GRACED was not sacrificed for the sake of higher spatiotemporal resolution that GRACED provides. Continuing to update GRACED in a timely manner could help policymakers monitor energy and climate policies' effectiveness and make adjustments quickly.

4.
Sci Data ; 9(1): 684, 2022 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-36357411

RESUMEN

Cities in China are on the frontline of low-carbon transition which requires monitoring city-level emissions with low-latency to support timely climate actions. Most existing CO2 emission inventories lag reality by more than one year and only provide annual totals. To improve the timeliness and temporal resolution of city-level emission inventories, we present Carbon Monitor Cities-China (CMCC), a near-real-time dataset of daily CO2 emissions from fossil fuel and cement production for 48 major high-emission cities in China. This dataset provides territory-based emission estimates from 2020-01-01 to 2021-12-31 for five sectors: power generation, residential (buildings and services), industry, ground transportation, and aviation. CMCC is developed based on an innovative framework that integrates bottom-up inventory construction and daily emission estimates from sectoral activities and models. Annual emissions show reasonable agreement with other datasets, and uncertainty ranges are estimated for each city and sector. CMCC provides valuable daily emission estimates that enable low-latency mitigation monitoring for cities in China.


Asunto(s)
Dióxido de Carbono , Combustibles Fósiles , Carbono/análisis , Dióxido de Carbono/análisis , China , Ciudades , Cambio Climático
5.
Sci Data ; 9(1): 533, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-36050332

RESUMEN

Building on near-real-time and spatially explicit estimates of daily carbon dioxide (CO2) emissions, here we present and analyze a new city-level dataset of fossil fuel and cement emissions, Carbon Monitor Cities, which provides daily estimates of emissions from January 2019 through December 2021 for 1500 cities in 46 countries, and disaggregates five sectors: power generation, residential (buildings), industry, ground transportation, and aviation. The goal of this dataset is to improve the timeliness and temporal resolution of city-level emission inventories and includes estimates for both functional urban areas and city administrative areas that are consistent with global and regional totals. Comparisons with other datasets (i.e. CEADs, MEIC, Vulcan, and CDP-ICLEI Track) were performed, and we estimate the overall annual uncertainty range to be ±21.7%. Carbon Monitor Cities is a near-real-time, city-level emission dataset that includes cities around the world, including the first estimates for many cities in low-income countries.

6.
Innovation (Camb) ; 3(1): 100182, 2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-34988539

RESUMEN

Precise and high-resolution carbon dioxide (CO2) emission data is of great importance in achieving carbon neutrality around the world. Here we present for the first time the near-real-time Global Gridded Daily CO2 Emissions Dataset (GRACED) from fossil fuel and cement production with a global spatial resolution of 0.1° by 0.1° and a temporal resolution of 1 day. Gridded fossil emissions are computed for different sectors based on the daily national CO2 emissions from near-real-time dataset (Carbon Monitor), the spatial patterns of point source emission dataset Global Energy Infrastructure Emissions Database (GID), Emission Database for Global Atmospheric Research (EDGAR), and spatiotemporal patters of satellite nitrogen dioxide (NO2) retrievals. Our study on the global CO2 emissions responds to the growing and urgent need for high-quality, fine-grained, near-real-time CO2 emissions estimates to support global emissions monitoring across various spatial scales. We show the spatial patterns of emission changes for power, industry, residential consumption, ground transportation, domestic and international aviation, and international shipping sectors from January 1, 2019, to December 31, 2020. This gives thorough insights into the relative contributions from each sector. Furthermore, it provides the most up-to-date and fine-grained overview of where and when fossil CO2 emissions have decreased and rebounded in response to emergencies (e.g., coronavirus disease 2019 [COVID-19]) and other disturbances of human activities of any previously published dataset. As the world recovers from the pandemic and decarbonizes its energy systems, regular updates of this dataset will enable policymakers to more closely monitor the effectiveness of climate and energy policies and quickly adapt.

8.
Sci Data ; 7(1): 392, 2020 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-33168822

RESUMEN

We constructed a near-real-time daily CO2 emission dataset, the Carbon Monitor, to monitor the variations in CO2 emissions from fossil fuel combustion and cement production since January 1, 2019, at the national level, with near-global coverage on a daily basis and the potential to be frequently updated. Daily CO2 emissions are estimated from a diverse range of activity data, including the hourly to daily electrical power generation data of 31 countries, monthly production data and production indices of industry processes of 62 countries/regions, and daily mobility data and mobility indices for the ground transportation of 416 cities worldwide. Individual flight location data and monthly data were utilized for aviation and maritime transportation sector estimates. In addition, monthly fuel consumption data corrected for the daily air temperature of 206 countries were used to estimate the emissions from commercial and residential buildings. This Carbon Monitor dataset manifests the dynamic nature of CO2 emissions through daily, weekly and seasonal variations as influenced by workdays and holidays, as well as by the unfolding impacts of the COVID-19 pandemic. The Carbon Monitor near-real-time CO2 emission dataset shows a 8.8% decline in CO2 emissions globally from January 1st to June 30th in 2020 when compared with the same period in 2019 and detects a regrowth of CO2 emissions by late April, which is mainly attributed to the recovery of economic activities in China and a partial easing of lockdowns in other countries. This daily updated CO2 emission dataset could offer a range of opportunities for related scientific research and policy making.


Asunto(s)
Dióxido de Carbono/análisis , Materiales de Construcción/análisis , Monitoreo del Ambiente , Emisiones de Vehículos/análisis , COVID-19 , Infecciones por Coronavirus , Pandemias , Neumonía Viral
9.
Nat Commun ; 11(1): 5172, 2020 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-33057164

RESUMEN

The COVID-19 pandemic is impacting human activities, and in turn energy use and carbon dioxide (CO2) emissions. Here we present daily estimates of country-level CO2 emissions for different sectors based on near-real-time activity data. The key result is an abrupt 8.8% decrease in global CO2 emissions (-1551 Mt CO2) in the first half of 2020 compared to the same period in 2019. The magnitude of this decrease is larger than during previous economic downturns or World War II. The timing of emissions decreases corresponds to lockdown measures in each country. By July 1st, the pandemic's effects on global emissions diminished as lockdown restrictions relaxed and some economic activities restarted, especially in China and several European countries, but substantial differences persist between countries, with continuing emission declines in the U.S. where coronavirus cases are still increasing substantially.


Asunto(s)
Contaminantes Atmosféricos/análisis , Dióxido de Carbono/análisis , Infecciones por Coronavirus/epidemiología , Neumonía Viral/epidemiología , Contaminantes Atmosféricos/economía , Betacoronavirus , COVID-19 , Dióxido de Carbono/economía , Infecciones por Coronavirus/economía , Infecciones por Coronavirus/prevención & control , Monitoreo del Ambiente , Combustibles Fósiles/análisis , Combustibles Fósiles/economía , Humanos , Industrias/economía , Dióxido de Nitrógeno/análisis , Dióxido de Nitrógeno/economía , Pandemias/economía , Pandemias/prevención & control , Neumonía Viral/economía , Neumonía Viral/prevención & control , SARS-CoV-2
10.
Dalton Trans ; 49(28): 9668-9679, 2020 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-32609137

RESUMEN

In this study, a two-step hydrothermal method is used to prepare NiCo2O4@NiMoO4 nanoscale materials for periodic stability supercapacitors. The synthesized product can be directly used as the electrode material of the supercapacitor, and its specific capacitance is 685.7 C g-1. The composite electrode NiCo2O4@NiMoO4 is used as the positive electrode and the hybrid capacitor is assembled. Meanwhile, at the power density of 4050 W kg-1, the energy density is 96.3 W h kg-1, and the capacitance retention is 100% after 10 000 cycles. At the same time, when the composite is used as a catalyst, it exhibits OER overvoltage (300 mV), HER overvoltage (170 mV) and a low battery voltage of 1.65 V at 10 mA cm-2. After 14 hours of long-term use, NiCo2O4@NiMoO4 maintained good stability, indicating that its structure further improved the electrochemical performance, providing a great advantage for the study of low-cost electrode materials for overall water splitting.

11.
J Nanosci Nanotechnol ; 18(6): 4065-4071, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29442744

RESUMEN

Herein, a novel visible-light-driven heterojunction AgI/WO3 nanocomposite was successfully prepared using a facile two-step hydrothermal-precipitation process and applied for photodegradation of organic pollutants. The information of phase structures, morphology, optical properties of the asprepared samples was analysed in detail by XRD, TEM, EDS, STEM, DRS measurement and so on. Formation of the heterostructure and intimate interactions between AgI and WO3 can promote highly effective photogenerated electron-hole pairs separation, which enable the heterojuctions to perform excellent photocatalytic activity as greatly enhanced photocatalysts compared to that of pristine AgI and WO3 for decomposing Rhodamine B (RhB) dye under visible light irradiation. In addition, the AgI/WO3 (1:1) nanocomposites exhibit optimal photocatalytic activity. Moreover, the as-prepared samples exhibit good stability, which is favorable for its potential application. Additionally, we have an analysis on a possible photocatalytic mechanism based on trapping experiments together with other experimental results.

12.
Astrobiology ; 17(12): 1219-1232, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29148825

RESUMEN

One signature of life on Earth is the vegetation red edge (VRE) feature of land plants, a dramatic change of reflectivity at wavelength near 0.7 µm. Potentially habitable planets around M dwarfs are tidally locked, which can limit the distribution of land plants. In this study, we used a biogeochemical model to investigate the distribution of land plants on potentially habitable planets around M dwarfs driven by climate data produced in a general circulation model (GCM). When considering the effects of clouds, the observation time needed for VRE detection on nearby p = 1 exoplanets around nearby M dwarfs is on the order of days using a 25 m2 telescope if a large continent faces Earth during observations. For p = 1.5 exoplanets, the detection time could be similar if land plants developed the capability to endure a dark/cold environment for extended periods of time and the continent configuration favors observations. Our analysis suggests that hypothetical exovegetation VRE features are easier to detect than Earth vegetation and that VRE detection is possible for nearby exoplanets even under cloudy conditions. Key Words: Vegetation red edge-Exoplanets-M dwarfs-Biosignature detection. Astrobiology 17, 1219-1232.


Asunto(s)
Clima , Embryophyta/crecimiento & desarrollo , Medio Ambiente Extraterrestre , Planetas , Estrellas Celestiales , Planeta Tierra , Exobiología , Vida , Modelos Teóricos
13.
PLoS One ; 11(9): e0162663, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27617439

RESUMEN

BACKGROUND: The decomposition of plant material in arid ecosystems is considered to be substantially controlled by water and N availability. The responses of litter decomposition to external N and water, however, remain controversial, and the interactive effects of supplementary N and water also have been largely unexamined. METHODOLOGY/PRINCIPAL FINDINGS: A 3.5-year field experiment with supplementary nitrogen and water was conducted to assess the effects of N and water addition on mass loss and nitrogen release in leaves and fine roots of three dominant plant species (i.e., Artemisia halondendron, Setaria viridis, and Phragmites australis) with contrasting substrate chemistry (e.g. N concentration, lignin content in this study) in a desertified dune grassland of Inner Mongolia, China. The treatments included N addition, water addition, combination of N and water, and an untreated control. The decomposition rate in both leaves and roots was related to the initial litter N and lignin concentrations of the three species. However, litter quality did not explain the slower mass loss in roots than in leaves in the present study, and thus warrant further research. Nitrogen addition, either alone or in combination with water, significantly inhibited dry mass loss and N release in the leaves and roots of the three species, whereas water input had little effect on the decomposition of leaf litter and fine roots, suggesting that there was no interactive effect of supplementary N and water on litter decomposition in this system. Furthermore, our results clearly indicate that the inhibitory effects of external N on dry mass loss and nitrogen release are relatively strong in high-lignin litter compared with low-lignin litter. CONCLUSION/SIGNIFICANCE: These findings suggest that increasing precipitation hardly facilitates ecosystem carbon turnover but atmospheric N deposition can enhance carbon sequestration and nitrogen retention in desertified dune grasslands of northern China. Additionally, litter quality of plant species should be considered when modelling the carbon cycle and nutrient dynamics of this system.


Asunto(s)
Pradera , Nitrógeno/química , Agua , Mongolia , Hojas de la Planta , Suelo
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