bluuebunny/crossref_metadata_2025 huggingface dataset:
Metodologias Ativas em ensino-aprendizagem de Geometria Descritiva: do Concreto ao Abstrato.
Authors: De Souza Estela Maris , Miguel Pollyanna Coutinho
Published: June 2021

No ensino-aprendizagem de Geometria Descritiva no curso de Arquitetura e Urbanismo, no intuito de dirimir o impacto negativo com relação à disciplina, adotou-se um método que chamamos do concreto ao abstrato. Nesse método adotamos uma abordagem diferente do ensino-aprendizagem clássico da geometria descritiva que parte do ponto, o que denominamos abstrato para o concreto, que denominamos o tridimensional. Além da inversão da abordagem ainda incluímos metodologias ativas nesse processo que vão desde origami até o uso de ferramentais digitais. Além da apresentação do método “do concreto ao abstrato” ainda foi feita uma pesquisa entre os alunos do curso para que pudéssemos avaliar a aplicabilidade do método durante os três semestres de funcionamento do curso.
A geometria oculta das calçadas de Paris
Authors: Cattani Airton
Published: June 2021

Embora nem sempre percebida, a geometria está presente em todos os aspectos de nosso cotidiano, manifestando-se ora explicitamente, ora de maneira mais discreta, de modo que tenhamos que fazer um esforço para percebê-la. Procurando mostrar que sempre há algo onde aparentemente não há nada, este relato apresenta os resultados de uma pesquisa visual sobre as calçadas de Paris, salientando sua geometria casual, provavelmente pouco percebida pelos pedestres. Os resultados mostram que, apesar de sua aparentemente falta de expressividade, as calçadas da cidade “escondem” uma geometria própria e espontânea, fruto de intervenções feitas por anônimos operários que, involuntariamente, deixam suas marcas sobre os pavimentos, conferindo-lhes um aspecto peculiar sob o ponto de vista da geometria. A pesquisa dá seguimento às investigações que o autor vem desenvolvendo desde 2005 sobre o tema calçadas urbanas.
O desenho de arquitetura e sua evolução: estudo de casos na revista Acrópole
Authors: Ramires Giovana , Dias Maria Angela
Published: June 2021

O artigo em questão, tem como tema central o desenho como meio de expressão e comunicação do arquiteto e como objeto de estudo os desenhos de arquitetura no campo das revistas especializadas, especificamente da revista Acrópole. O objetivo deste artigo é ensaiar uma metodologia para análise dos desenhos de projeto para traçar uma evolução do desenho de arquitetura, ao longo de um período específico, e, assim, fundamentar, em uma etapa seguinte, por meio da pesquisa da tese de doutorado, a identificação de possíveis formas de representação gráfica do desenho de arquitetura no futuro. Para tanto, analisamos, por meio do preenchimento de quadros (método a ser exposto ao longo do artigo), desenhos selecionados da revista em 16 momentos, entre o ano de 1945 e o ano de 1971, para desse modo, termos condições de fazer uma comparação entre eles. Após a análise dos quadros e reflexão sobre os resultados obtidos, foi possível observar que a representação dos desenhos de arquitetura se modificou, com o passar dos anos.
Case report: Detection of aadB and tet (39) on the plasmid of Acinetobacter baumannii TN81 in Vietnam through next-generation sequencing and bioinformatics analysis
Authors: Ha Vu Nhi , Thanh Kieu Chi , Son Nguyen Thai , Thang Dao Van , Hoang Tran Huy
Published: June 2021

Acinetobacter baumannii (A. baumannii) is currently ranked as the frst concern for the development of new antibiotics due to its capacity of resistance to all available families of antibiotics. The most common mechanism of antibiotic resistance development in A. baumannii is through the acquisition of mobile genetic elements such as plasmid, transposon and integrons carrying resistance genes. A. baumannii strain TN81 was isolated from sputum specimen of a 45-year-old man at Thanh Nhan Hospital (Hanoi, Vietnam) and confrmed to be a multidrug resistance strain with high minimum inhibitory concentration value of 8/9 type of antibiotics, especially colistin. De novo assembly of the whole genome shotgun sequence of strain TN81 yielded an estimated genome size of 3,739,193 bp with 593 contigs and N50 is 9,126 bp. MLST analysis showed that TN81 belongs to ST164, which was frst reported as genome assembly in Vietnam. Resistance genes identifcation through database found that TN81 contained 12 genes encoding for antibiotic resistance. Notably, we performed de novo assembly of plasmid through short read sequence and identifed two potential plasmid-encoded antibiotic resistance genes (ant(2’’)-Ia / aadB and tet (39), which were reported for the first time as in ST164 group. This study aimed to investigate the plasmid-containing antibiotic resistance genes from a nosocomial isolate of Acinetobacter baumannii. Conclusively, all of these results would be crucial information on antibiotic resistance in A. baumannii in Vietnam.
Knowledge and practice of handwashing with soap among mothers of children aged under 11 in some mountainous provinces in Vietnam, 2019
Authors: Anh Tran Quynh , Ly Le Thi Huong , Huong Nguyen Thi Lien
Published: June 2021

Handwashing with soap (HWWS) practice among mothers is critical in preventing childhood illnesses. This study aims to describe HWWS knowledge and practice among mothers of children aged under 11 and associated factors. This cross-sectional study was conducted on 319 mothers in 4 provinces in Vietnam, namely Dien Bien, Tuyen Quang, Hoa Binh, and Dak Lak, representing the region Northern Mountains and Central Highlands 2019. Knowledge of HWWS is measured through questionnaire interviews. HWWS practice is measured by the “Sticker Diary” method. Results show that while the proportion of mothers with knowledge on HWWS after defecation/toilet/using latrine is 84.6%, only 19.4% of mothers said that they need to HWWS after cleaning a child’s bottom/child’s feces, 17.6% before feeding children, and 39.2% HWWS before cooking/serving food. Less than 50% of mothers practice washing their hands with soap at critical times. The study shows a signifcant association between attributes such as educational level, occupation, economic status, and knowledge of HWWS. The study also fnds an association between the ethnic group, fnancial situation, knowledge, and practice HWWS among mothers of children under age 11.
Reliability and validity of the Internet Gaming Disorder-20 Test among Vietnamese teenagers
Authors: Thanh Pham Hai , Uyen Hoang Thu , Toan Do Thi Thanh , Minh Luu Ngoc , Hiep Nong Bich , Trang Le Thi Thu , Thai Pham Quang , Hoat Luu Ngoc , Son Dinh Thai
Published: June 2021

To validate the Vietnamese version Internet Gaming Disorder-20 (VN-IGD-20) Test for teenagers, a survey among 349 gamers, who were accepted in the interview, from secondary and high schools from 28 game stores was conducted in Hanoi, Vietnam. The IGD-20 Test comprised 20 items with six different dimensions, using a 5-point Likert scale. Exploratory factor analysis (EFA) and confrmatory factor analysis (CFA) were used to examine the validation; Cronbach’s Alpha was performed to test the reliability; and Latent class analysis (LCA) was applied to identify the level of internet gaming disorder (IGD). Moreover, the ROC curve diagram was used with the highest Youden’s Index parameter to determine the best cut-off point. CFA proved that the VN-IGD-Test with 17 items, which was divided into fve-factor dimensions. The model indexes of the Vietnamese questionnaire included RMSEA = 0.053; SRMR = 0.052; GFI = 0.929; TLI = 0.908 and CFI = 0.927. The values for Cronbach’s alpha coeffcient of each dimension ranged from 0.823 to 0.840. The LCA found out four levels of IGD: casual gamers, regular gamers, low-risk engaged gamers, and high-risk engaged gamers. Additionally, the optimal empirical cut-off point with the highest Youden’s Index was 47.5 (out of 85). The present study fndings illustrated that the VN-IGD-17 Test could be used as a valid and reliable tool for assessing internet gaming disorder in Vietnamese teenagers.
FUN LEARNING MELALUI MEDIA WHATSAPP PADA PEMBELAJARAN JARAK JAUH UNTUK KELAS 1 SEKOLAH DASAR
Authors: ASMAWADI ANDI
Published: June 2021

Tujuan penelitian ini adalah mengelaborasi pemanfaatan metode fun learning yaitu pembelajaran menyenangkan menggunakan media Whatsapp guna meningkatkan minta belajar siswa kelas 1 sekolah dasar. Masalah yang dibahas di dalam penelitian ini adalah tentang bagaimana pergeseran kegiatan pembelajaran dari metode konvensional kepada pembelajaran jarak jauh menggunakan media bantuan dengan pemanfaatan Teknologi Informasi dan Komunikasi yang tersedia. Kegiatan pembelajaran yang menyenangkan khususnya bagi siswa kelas satu sekolah dasar yang masih harus didampingi oleh guru dan siswa. Fun learning diterapkan melalui media WA Grup dengan berbagai kreatifitas guru dan siswa sehingga pembelajaran menjadi menyenangkan. Penelitian ini menerapkan metode penelitian kepustakaan yang mengeksplorasi berbagai isu yang berkaitan dengan pemanfaatan TIK dalam pembelajaran khususnya kolaborasi dengan metode fun learning (melalui berbagai hasil penelitian dan pengembangan, jurnal ilmiah, prosiding pertemuan ilmiah, dan publikasi lainnya yang relevan) guna menerapkan model pembelajaran yang berfokus pada peserta didik. Hasil penelitian ini menunjukkan bahwa metode fun learning sangat cocok diterapkan dalam pembelajaran khususnya jenjang sekolah dasar dimana siswa bisa berkreasi dan belajar menyenangkan dengan memanfaatkan bantua media sosial yang ada.
UPAYA MENINGKATKAN HASIL BELAJAR MATEMATIKA TEMA DIRIKU MELALUI METODE PERMAINAN PAPAN SAKU SISWA KELAS I SDN 01 KURAIKECAMATAN SULIKI
Authors: ISMANELI ERVA
Published: June 2021

Penelitian ini bertujuan untuk meningkatkan upaya meningkatkan hasil belajar matematika siswa kelas SDN 01 kurai kecamatan suliki tahun pelajaran 2018/2019 dengan menggunakan metode permainan saku.Subjek dalam penelitian ini adalah siswa kelas I SDN 01 Kurai yang berjumlah 15 Orang yang terdiri 10 orang laki-laki dan 5 orang perempuan. Rata-rata hasil observasi metode permainan papan saku pada setiap sikluis yaitu : data awal (64,6%), siklus pertama (77%), siklus kedua (86,7%). Hasil nilai rata-rata penilaian belajar dan jumlah siswa yang dinyatakan tuntas belajar pada setiap siklus yaitu siklus I mempunyai nilai rata-rata 77 dengan siswa yang tuntas 9, siklus II mempunyai nilai rata-rata 87 dengan siswa yang tuntas 14 siswa. Berdasarkan angket observasi setiap siklus maka diperoleh peningkatan pada setiap siklus yaitu pada siklus I (77 %), siklus II (86,7%).
O MANEJO FLORESTAL SUSTENTÁVEL DA CAATINGA
Authors: Silva Adriele Gomes da , Vilar Larissa Oliveira , Vilar Viviane Oliveira , Coelho Fernando Pinto , Acioli Nayara Rithelly dos Santos , Ramos Ramon Brilhante Gonçalves Araújo , Moreira Jefferson Gomes , Diares Thiago Rocha , Silva Danielly Ferreira da , Cruz Mayra Santos da , Moura Ricardo Gonzaga de
Published: June 2021

Sabendo da importância e das peculiaridades da caatinga traremos por meio desse artigo esclarecimentos e informações que conscientizem os pequenos e médios produtores do quanto a ação antrópica tem afetado negativamente o bioma, colocando inclusive algumas áreas da região em risco de desertificação. Para tanto, foi utilizado o método de pesquisa exploratória pois a atual situação enfrentada pelo país impossibilita uma pesquisa de campo, mas vale ressaltar que esse artigo não foi prejudicado por tal situação visto que o tipo de pesquisa utilizada e seus parâmetros técnicos de estudo bibliográfico nos garantiu ricas fontes de informações. Dessa forma, foi possível conseguir dados que comprovam a degradação constante que a caatinga vem sofrendo ao longo dos anos e mostra a problematização que a interferência inconsequente do homem traz, colocando em risco o bioma. Portanto, fazer essa  parcela específica da população saber sobre o que é e quais os benefícios do uso correto do solo e da vegetação por meio da conscientização e do manejo sustentável do bioma é importante e indispensável para garantir a preservação desse bioma exclusivamente brasileiro.
Improved gridded ammonia emission inventory in China
Authors: Li Baojie , Chen Lei , Shen Weishou , Jin Jianbing , Wang Teng , Wang Pinya , Yang Yang , Liao Hong
Published: June 2021

Abstract. As a major alkaline gas in the atmosphere, NH3 significantly impacts atmospheric chemistry, ecological environment, and biodiversity. Gridded NH3 emission inventories can significantly affect the accuracy of model concentrations and play a crucial role in the refinement of mitigation strategies. However, several uncertainties are still associated with existing NH3 emission inventories in China. Therefore, in this study, we focused on improving fertilizer application-related NH3 emission inventories. We comprehensively evaluated the dates and times of fertilizer application to the major crops that are cultivated in China, improved the spatial allocation methods for NH3 emissions from croplands with different rice types, and established a gridded NH3 emission inventory for mainland China with a resolution of 5 min × 5 min in 2016. The results showed that the atmospheric NH3 emissions in mainland China amounted to 12.11 Tg, with livestock waste (44.8 %) and fertilizer application (38.6 %) being the two main NH3 emission sources in China. Obvious spatial differences in NH3 emissions were also observed, and high emissions were predominantly concentrated in North China. Further, NH3 emissions tended to be high in summer and low in winter, and the ratio for the July–January period was 3.08. Furthermore, maize and rice fertilization in summer was primarily responsible for the increase in NH3 emissions in China, and the evaluation of the spatial and temporal accuracy of the NH3 emission inventory established in this study using the WRF-Chem and ground station- and satellite-based observations showed that it was more accurate than other inventories.
Impact of COVID-19 pandemic related to lockdown measures on tropospheric NO2 columns over Île-de-France
Authors: Pazmiño Andrea , Beekmann Matthias , Goutail Florence , Ionov Dmitry , Bazureau Ariane , Nunes-Pinharanda Manuel , Hauchecorne Alain , Godin-Beekmann Sophie
Published: June 2021

Abstract. The evolution of NO2, considered as proxy for air pollution, was analyzed to evaluate the impact of 1st lockdown (March 17th – May 10th 2020) over île-de-France region (Paris and surroundings). Tropospheric NO2 columns measured by two UV-Visible SAOZ spectrometers were analyzed to compare the evolution of NO2 between urban and suburban sites during the lockdown. The urban site is the observation platform QUALAIR (48°50' N/2°21' E) on the Pierre et Marie Curie Campus of Sorbonne University in the center of Paris. The suburban site is located at Guyancourt (48°46' N/2°03' E), University of Versailles Saint Quentin, 24 km south-west of Paris. Tropospheric NO2 columns above Paris and Guyancourt have shown similar values during the whole lockdown period from March to May 2020. One decade datasets were filtered to consider air masses at both sites with similar meteorological conditions. The median NO2 columns, as well as the surface measurements of AIPARIF (Air Quality Observatory in Ile de France) during the lockdown period in 2020 were compared to the extrapolated values estimated from a linear trend analysis for the 2011–2019 period at each station. Negative NO2 trends of −1.5 Pmolec cm−2 yr−1 (~−6.3 % yr−1) are observed from the columns and of −2.2 μg m−3 yr−1 (~−3.6 % yr−1) from the surface concentration. The negative anomaly in tropospheric columns in 2020 attributed to lockdown (and related emission reductions) was found to be 56 % at Paris and 46 % at Guyancourt, respectively. Similar anomaly was found in the data of surface concentrations, amounting for 53 % and 28 % at the urban and suburban sites, accordingly.
Atmospheric composition in the European Arctic and 30 years of the Zeppelin Observatory, Ny-Ålesund
Authors: Platt Stephen M. , Hov Øystein , Berg Torunn , Breivik Knut , Eckhardt Sabine , Eleftheriadis Konstantinos , Evangeliou Nikolaos , Fiebig Markus , Fisher Rebecca , Hansen Georg , Hansson Hans-Christen , Heintzenberg Jost , Hermansen Ove , Heslin-Rees Dominic , Holmén Kim , Hudson Stephen , Kallenborn Roland , Krejci Radovan , Krognes Terje , Larssen Steinar , Lowry David , Lund Myhre Cathrine , Lunder Chris , Nisbet Euan , Nizetto Pernilla B. , Park Ki-Tae , Pedersen Christina A. , Aspmo Pfaffhuber Katrine , Röckmann Thomas , Schmidbauer Norbert , Solberg Sverre , Stohl Andreas , Ström Johan , Svendby Tove , Tunved Peter , Tørnkvist Kjersti , van der Veen Carina , Vratolis Stergios , Yoon Young Jun , Yttri Karl Espen , Zieger Paul , Aas Wenche , Tørseth Kjetil
Published: June 2021

Abstract. The Zeppelin Observatory (78.90° N, 11.88° E) is located on the Zeppelin Mountain at 472 m above sea level on Spitsbergen, the largest island of the Svalbard archipelago. Established in 1989, the observatory is part of the “Ny-Ålesund Research Station” and an important atmospheric measurement site, one of only a few in the high Arctic and as a part of several European and global monitoring programs and research infrastructures, notably the European Monitoring and Evaluation Programme (EMEP), the Arctic Monitoring and Assessment Programme (AMAP), the Global Atmosphere Watch (GAW), the Aerosols, Clouds, and Trace gases Research InfraStructure (ACTRIS), the Advanced Global Atmospheric Gases Experiment (AGAGE) network, and the Integrated Carbon Observation System (ICOS). The observatory is jointly operated by the Norwegian Polar Institute (NPI), Stockholm University and the Norwegian Institute for Air Research (NILU). Here we detail the establishment of the Zeppelin Observatory including historical measurements of atmospheric composition in the European Arctic leading to its construction. We present a history of the measurements at the observatory and review the current state of the European Arctic atmosphere, including results from trends in greenhouse gases, chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), other traces gases, persistent organic pollutants (POPs) and heavy metals, aerosols and Arctic haze, and atmospheric transport phenomena.
The climate impact of COVID-19-induced contrail changes
Authors: Gettelman Andrew , Chen Chieh-Chieh , Bardeen Charles G.
Published: June 2021

Abstract. The COVID-19 pandemic caused significant economic disruption in 2020 and severely impacted air traffic. We use a state-of-the-art Earth system model and ensembles of tightly constrained simulations to evaluate the effect of the reductions in aviation traffic on contrail radiative forcing and climate in 2020. In the absence of any COVID-19-pandemic-caused reductions, the model simulates a contrail effective radiative forcing (ERF) of 62 ± 59 mW m−2 (2 standard deviations). The contrail ERF has complex spatial and seasonal patterns that combine the offsetting effect of shortwave (solar) cooling and longwave (infrared) heating from contrails and contrail cirrus. Cooling is larger in June–August due to the preponderance of aviation in the Northern Hemisphere, while warming occurs throughout the year. The spatial and seasonal forcing variations also map onto surface temperature variations. The net land surface temperature change due to contrails in a normal year is estimated at 0.13 ± 0.04 K (2 standard deviations), with some regions warming as much as 0.7 K. The effect of COVID-19 reductions in flight traffic decreased contrails. The unique timing of such reductions, which were maximum in Northern Hemisphere spring and summer when the largest contrail cooling occurs, means that cooling due to fewer contrails in boreal spring and fall was offset by warming due to fewer contrails in boreal summer to give no significant annual averaged ERF from contrail changes in 2020. Despite no net significant global ERF, because of the spatial and seasonal timing of contrail ERF, some land regions would have cooled slightly (minimum −0.2 K) but significantly from contrail changes in 2020. The implications for future climate impacts of contrails are discussed.
Ideas and perspectives: Ushering the Indian Ocean into the UN Decade of Ocean Science for Sustainable Development (UNDOSSD) through marine ecosystem research and operational services – an early career's take
Authors: Nimit Kumar
Published: June 2021

Abstract. The Indian Ocean Rim hosts many of the world's underdeveloped and emerging
economies that depend on the ocean resources for the livelihoods of the
populations of millions. Operational ocean information services
cater to the requirements of managers and end-users to efficiently harness
those resources and to ensure safety. Fishery information is not the only
operational service that will be needed to empower such communities in the
coming decades. Coral bleaching alerts, SCUBA (self-contained underwater breathing apparatus)-assisting advisories, conservation or ecotourism assisting services (e.g. TurtleWatch or WhaleWatch),
poaching and/or by-catch reduction support and jellyfish, micro-plastic and oil spill watching to name a few, but not an exhaustive list, of the services that are needed operationally. This paper outlines the existing tools and explores the ongoing research that has potential to convert the findings into operational services in near- to midterm.
Episodic subduction patches in the western North Pacific identified from BGC-Argo float Data
Authors: Chen Shuangling , Wells Mark L. , Huang Rui Xin , Xue Huijie , Xi Jingyuan , Chai Fei
Published: June 2021

Abstract. Subduction associated with mesoscale eddies is an important but difficult to observe process that can efficiently export carbon and oxygen to the mesopelagic zone (100–1000 db). Using a novel BGC-Argo dataset covering the western North Pacific (20–50° N, 120–180° E), we identified imprints of episodic subduction using anomalies in dissolved oxygen and spicity, a water mass marker. These subduction patches were present in 4.0 % (288) of the total profiles (7,120) between 2008 and 2019, situated mainly in the Kuroshio Extension region between March and August (70.6 %). Unlike eddy subduction processes observed at higher latitudes, roughly half (52 %) of these episodic events injected carbon- and oxygen-enriched waters below the annual permanent thermocline depth (450 db), with > 20 % occurring deeper than 600 db. Export rates within these subductions are estimated to be on the order of 85–159 mg C m−2 day−1 and 175 to 417 mg O2 m−2 day−1. These mesoscale events would markedly increase carbon removal above that due to biological gravitational settling as well as oxygen ventilation in the region, both helping to support the nutritional and metabolic demands of mesopelagic organisms. Climate-driven patterns of increasing eddy kinetic energies in this region imply that the magnitude of these processes will grow in the future, meaning that these unexpectedly effective small-scale subduction processes need to be better constrained in global climate and biogeochemical models.
Mitigating Intensity of Urban Heat Island by Better Understanding on Urban Morphology and Anthropogenic Heat Dispersion
Authors: Yuan Chao , Mei Shuojun , He Wenhui , Adelia Ayu Sukma , Zhang Liqing
Published: June 2021

Anthropogenic heat is one of the key factors that causes intensive urban heat island due to its direct impact on ambient temperature in urban areas. Stagnated airflow due to closely packed tall buildings causes weak dilution and removal of anthropogenic heat. Consequently, research is critically needed to investigate the effect of urban morphology on anthropogenic heat dispersion and provide effective planning strategies to reduce UHI intensity, especially at the extreme scenario, such as with very low wind speed and high heat emission. This study provides scientific understanding and develops a GIS-based modelling tool to support decision-making in urban planning practice. We start from a computational parametric study at the neighbourhood scale to investigate the impact of urban morphology on heat dispersion. Site coverage ratio ( ), and frontal area density ( ) are two urban morphological parameters. Ten parametric cases with two heat emission scenarios are designed to study representative urban areas. Furthermore, based on the energy conservation within the urban canopy layer, we develop a semi-empirical model to estimate spatially-averaged in-canopy air temperature increment, in which the exchange velocity between the street canyon and overlying atmosphere is estimated by the Bentham and Britter model. The performance of the new model is validated by cross-comparing with CFD results from the parametric study. By applying this new model, the impact of anthropogenic heat on air temperature is mapped in residential areas of Singapore for both long-term annually averaged and short-term extreme low wind speed to improve urban climate sustainability and resilience.
El Niño teleconnection to the Euro-Mediterranean late-winter: the role of extratropical Pacific modulation 
Authors: Benassi Marianna , Conti Giovanni , Gualdi Silvio , Ruggieri Paolo , Materia Stefano , García-Serrano Javier , Palmeiro Froila M. , Batté Lauriane , Ardilouze Constantin
Published: June 2021

El Niño Southern Oscillation (ENSO) represents the major driver of interannual climate variability at global scale. Observational and model-based studies have fostered a long-standing debate on the shape and intensity of the ENSO influence over the Euro-Mediterranean sector. Indeed, the detection of this signal is strongly affected by the large internal variability that characterizes the atmospheric circulation in the North Atlantic-European (NAE) region. This study explores if and how the low-frequency variability of North Pacific sea surface temperature (SST) may impact the El Niño-NAE teleconnection in late winter, which consists of a dipolar pattern between middle and high latitudes. A set of idealized atmosphere-only experiments, prescribing different phases of the anomalous SST linked to the Pacific Decadal Oscillation (PDO) superimposed onto an El Niño-like forcing in the tropical Pacific, has been performed in a multi-model framework, in order to assess the potential modulation of the positive ENSO signal. The modelling results suggest, in agreement with observational estimates, that the PDO negative phase (PDO-) may enhance the amplitude of the El Niño-NAE teleconnection, while the dynamics involved appear to be unaltered. On the other hand, the modulating role of the PDO positive phase (PDO+) is not reliable across models. This finding is consistent with the atmospheric response to the PDO itself, which is robust and statistically significant only for PDO-. Its modulation seems to rely on the enhanced meridional SST gradient and the related turbulent heat-flux released along the Kuroshio-Oyashio extension. PDO- weakens the North Pacific jet, whereby favoring more poleward propagation of wave activity, strengthening the El Niño-forced Rossby wave-train.

These results imply that there might be conditional predictability for the interannual Euro-Mediterranean climate variability depending on the background state.
Analysis of wind power under heat wave conditions in southern Europe
Authors: Molina María Ofelia , Sánchez Enrique , Gutiérrez Claudia , Ortega María
Published: June 2021

In recent years, renewable energy is gaining importance in the energy mix, increasing the dependence of the energy system on the weather. Studies have been mainly focused on atmospheric patterns related to wind energy production in winter, as wind resource in Europe is higher for this season, but also because it is when there is a larger and more stable heating demand in Europe as a whole. However, it can be seen that summer energy demand can be as high as in winter in southern European countries, especially on heat wave days (calculated from E-OBS maximum temperature observations). Therefore, the objective of this work is to study the effect of heat waves on wind power generation. Summer climate conditions present reduced wind values, so a potential increase in energy demand due to heat wave conditions could compromise the total energy supply. We analyse the main atmospheric patterns in summer (1989-2019) and how these are related to changes in wind energy production. The relationship between weather regimes and wind energy is examined using an energy model from ERA5 wind speed data at 100 m. Results show a demand increase in heat wave days and different responses in wind power, depending on the country and weather regime studied. The impact of extreme climate events, such as heat waves, on wind energy in conditions of high energy demand, should be considered in the energy supply strategic planning and control to minimize the impact of these events on an electricity system with high penetration of renewables.
Understanding land surface-atmosphere interactions at the diurnal scale from energetic and thermodynamic constraints
Authors: Kleidon Axel , Renner Maik , Panwar Annu , Ghausi Sarosh Alam
Published: June 2021

Land-atmosphere interactions are typically evaluated using numerical simulation models of increasingly greater complexity.  But what are the key, major constraints that determine the first-order controls of the land-atmosphere system?  Here, we present an alternative approach that is solely based on energetic and thermodynamic constraints of the coupled land-atmosphere system and show that this approach can reproduce observations at the diurnal scale very well.  The key concept we use is that turbulent heat fluxes are predominantly the result of an atmospheric heat engine that is driven by the heat input from the surface and that operates at the thermodynamic limit of maximum power.  This provides a closure for the magnitude of turbulent fluxes in the surface energy balance.  Interactions enter this approach mainly in two ways: First, the cooling effect of turbulent heat fluxes on surface temperature lowers the engine's efficiency, thereby setting the maximum power limit, and second, by heat storage changes in the lower atmosphere, which represent an entropy term inside the heat engine and alter the thermodynamic limit for power output.  Both effects are, however, well constrained by energy balances, yielding analytical solutions for energy balance partitioning during the day without the need for empirical parameters. The further partitioning into sensible and latent heat fluxes is obtained from the assumption of thermodynamic equilibrium at the surface where heat and moisture is added to the atmosphere (if sufficient soil water is accessible).  We then show that this approach works remarkably well in reproducing FluxNet observations over the diurnal cycle.  What this implies is that these physical constraints determine the first-order dynamics of the land-atmosphere system, enabling us to derive simple, physics-based estimates of climate, the dominant effects of vegetation, and the response of the coupled system to global climate change.
Investigation of the turbulent three-dimensional wind field in the near-wake of a full-scale wind turbine using synchronized scanning wind lidars
Authors: Angelou Nikolas , Sjöholm Mikael , Mikkelsen Torben
Published: June 2021

The objective of this work is to enhance the understanding of the mean wind and turbulence characteristics in the wake of a full-scale wind turbine.  Here, we present observations of the three-dimensional wind vector in the near wake of a wind turbine, a Vestas V52 with a 52-m rotor diameter.  The test turbine is located at the Risø campus of the Technical University of Denmark (DTU). The measurements were acquired using three, state-of-the-art, scanning, continuous-wave wind lidars, developed in DTU Wind Energy (Short-Range WindScanner). In our study, the area of focus was a vertical, two-dimensional plane at a distance of two rotor diameters from the wind turbine, in the downwind direction. Using the scanning lidars it was possible to derive spatially distributed estimations of the first and second-order moments of the wind vector within the vertical plane. The plane was within an area equal to 2.6 x 1.8 rotor diameters, towards the transverse and vertical direction respectively, covering a measuring range that included both the wake and free flow. The field test took place during a period of almost two weeks (July 2 - July 14, 2019). Approximately half of the time, the wind direction was favourable such that the measuring plane was covering a cross-section of the mean flow, which included the entire area where the wind speed deficit occurred. This data set enables the quantification of the wind speed deficit and the corresponding momentum deficit in the wake and reveals the turbulent layer that surrounds the mean wind speed deficit. Thus, allowing the investigation of the relation between the momentum fluxes and the local wind speed gradients, which is important for the understanding of the physical properties of the flow behind a wind turbine. Furthermore, we investigate the effect that wakes have on the vertical shear close to the ground, which can have a direct impact on the wind-surface interaction on the downwind side. Since the measuring plane was extended also to areas of the free flow, we compare the wind characteristics within the mean wake flow to the ones of the free flow. The knowledge of the features of the wake and the physical connection between the mean and turbulent flow provides a new detailed input for improved wake modelling. This is necessary for a more accurate prediction of the wake characteristics and can enable a more realistic quantification of the interaction between wind turbines in a wind farm, as well as the impact of the wake flow on the surrounding microclimate.
Evaluating sub-seasonal heatwave reforecasts of the ECMWF over Europe
Authors: Korhonen Natalia , Hyvärinen Otto , Kämäräinen Matti , Jylhä Kirsti
Published: June 2021

Severe heatwaves have harmful impacts on ecosystems and society. Early warning of heat waves help with decreasing their harmful impact. Previous research shows that the Extended Range Forecasts (ERF) of the European Centre for Medium-Range Weather Forecasts (ECMWF) have over Europe a somewhat higher reforecast skill for extreme hot summer temperatures than for long-term mean temperatures. Also it has been shown that the reforecast skill of the ERFs of the ECMWF was strongly increased by the most severe heat waves (the European heatwave 2003 and the Russian heatwave 2010).

Our aim is to be able to estimate the skill of a heat wave forecast at the time the forecast is given. For that we investigated the spatial and temporal reforecast skill of the ERFs of the ECMWF to forecast hot days (here defined as a day on which the 5 days running mean surface temperature is above its summer 90th percentile) in the continental Europe in summers 2000-2019. We used the ECMWF 2-meter temperature reforecasts and verified them against the ERA5 reanalysis. The skill of the hot day reforecasts was estimated by the symmetric extremal dependence index (SEDI) which considers both hit rates and false alarm rates of the hot day forecasts. Further, we investigated the skill of the heatwave reforecasts based on at which time steps of the forecast the hot days were forecasted. We found that on the mesoscale (horizontal scale of ~500 km) the ERFs of the ECMWF were most skillful in predicting the life cycle of a heat wave (lasting up to 25 days) about a week before its start and during its course. That is, on the mesoscale those reforecasts, in which hot day(s) were forecasted to occur during the first 7…11 days, were more skillful on lead times up to 25 days than the rest of the heat wave forecasts. This finding is valuable information, e.g., in the energy and health sectors while preparing for a coming heat wave.

The work presented here is part of the research project HEATCLIM (Heat and health in the changing climate) funded by the Academy of Finland.
Impact of the radiative forcing on the winter North Atlantic-European atmospheric circulation 
Authors: Ginesta Mireia , García-Serrano Javier , Gastineau Guillaume
Published: June 2021

The accelerated warming linked to climate change has become a topic of great interest due to its projected impact on ecosystems. In this work, we assess the causes and impacts of the anthropogenic radiative forcing on the North Atlantic-European atmospheric circulation in boreal winter (DJF). To isolate the response to radiative forcing, we have used two approaches, whose simulations follow the historical/scenario concentrations from CMIP6. The first approach consists of three 240-year simulations with the European Consortium – Earth System model version 3.3 (EC-EARTH v3.3) keeping fixed the radiative forcing at 1950, characterizing the Past climate, at 2000, representative of Present-day conditions, and at 2050, projecting the near-Future climate. The second approach makes use of the Large Ensemble (i.e. 24 members) of transient simulations performed with the Institut Pierre-Simon Laplace Coupled Model version 6 (IPSL-CM6), where three 10-year periods have been considered, namely 1949-1959, 1999-2009, and 2049-2059, assuming that the radiative forcing remains relatively constant in each of them. Results show that both approaches yield a consistent forced response, and that it scales linearly with radiative forcing, increasing in amplitude from Present-minus-Past to Future-minus-Present. At low latitudes, in the tropical Atlantic, the forced atmospheric response is characterized by a Gill-type baroclinic structure, where the anomalous anticyclonic circulation at upper levels reinforces the westerly wind at the equatorward flank of the North Atlantic jet. At high latitudes, the forced response is reminiscent of the ‘Arctic Amplification’ linked to sea-ice reduction, and the thermally-driven baroclinic structure can be seen over the Labrador Sea-Hudson Bay region. At mid-latitudes, the forced response shows a barotropic pattern, with a cyclonic (anticyclonic) circulation in the North Atlantic (Euro-Mediterranean) sector, pointing out a role for non-radiative, eddy-related effects.  
Predicting Climate Change over the multi-annual range: a perspective from CMCC Decadal Prediction System
Authors: Nicolì Dario , Bellucci Alessio , Ruggieri Paolo , Athanasiadis Panos , Fedele Giusy , Gualdi Silvio
Published: June 2021

After the early pioneering studies during the 2000s, and the first coordinated multi-model effort within the framework of the 5th Coupled Model Inter-comparison Project (CMIP5) in early 2010s, decadal climate predictions are now entering a more mature phase of their historical development. Near-term climate prediction activities have been recently endorsed by the World Climate Research Programme (WCRP) as one of the Grand Challenges in climate science research, and the Lead Centre for Annual-to-Decadal Climate Prediction, collecting hindcasts and forecasts from several contributing centres worldwide has been established by the WMO.

Here we present results from the CMIP6 DCPP-A decadal hindcasts produced with the CMCC decadal prediction system (CMCC DPS), based on the fully-coupled CMCC-CM2-SR5 dynamical model. A 10-member suite of 10-year retrospective forecasts, initialized every year from 1960 to 2019, is performed using a full-field initialization strategy.

The predictive skill for key quantities is assessed and compared with a non-initialized historical simulation, so as to verify the added value of initialization. In particular, the CMCC DPS is capable to skilfully reproduce past-climate surface temperature over the North Atlantic ocean, the Indian ocean and the Western Pacific ocean, as well as over most part of the continents. Beyond the contribution of the climate change, predictive skill emerges, among other regions, for the subpolar North Atlantic sea-surface temperatures, resembling the imprint of the extra-tropical part of the Atlantic Multidecadal Variability.

In terms of precipitation, CMCC DPS is able to capture most of the decadal variability over the Northern part of the Eurasian continent. Indeed, a set of regional diagnostics is aimed to investigate the process at stake behind this high predictive skill.
B-matrix estimation in the Copernicus European Regional Re-Analysis (CERRA)
Authors: El-Said Adam , Brousseau Pierre , Randriamampianina Roger , Ridal Martin
Published: June 2021

A new augmented Ensemble of Data Assimilations (EDA) technique, which estimates background error covariances (B-matrix), has been developed for the new Copernicus European Regional Re-Analysis (CERRA-EDA). CERRA-EDA has 10 members with two main pools of forecast differences: seasonal and daily. The seasonal component is pre-prepared (`offline') at reanalysis-resolution (5.5km). The new augmentation governs the time-dependent mixture of winter and summer differences of this seasonal component with respect to the time of year. The daily component is (`online') and averaged in moving succession over 2.5 days with subsequent B-matrix computation every 2 days. This daily component runs at 11km and the forecasts are interpolated to 5.5km prior to use. The seasonal-daily split is set to a fixed value of 80-20\% for CERRA production. The EDA is cycled 6-hourly while CERRA has a 3-hour analysis cycle. The B-matrix is modelled on a bi-Fourier limited area weather model, where dependence of vertical correlations on horizontal scale (non-separability), horizontal homogeneity and isotropy are assumed. The mass-wind and specific humidity fields are related via vorticity and geopotential and the relationships are estimated via multiple linear regressions enforcing simplified analogues of flow-dependence. 

We demonstrate the potential of CERRA-EDA to estimate rapid changes in weather regime change over Europe by assessing B-matrix statistics and forecast skill scores in a case study. The case study assesses two like-periods bearing different weather regimes, Mar-03 (blocking regime) and Mar-18 (NAO- regime). The aptitude of the B-matrix to reflect weather regime change is shown to be mostly dependent on the observation network in a given year. We also illustrate the impact of: change in observation networks over time, and varying the seasonal-daily split. This is shown through analysing the spatio-temporal evolution of background standard deviations. Finally, analysis and forecast skill scores up to 24-hours are also shown to offer improvements worth considering.
Downscaling and Verification of Maximum Wind Speeds by Using Artificial Neural Networks for New European Wind Atlas and Wind Farm Data 
Authors: Akın Melek , Öztopal Ahmet , Şahin Ahmet Duran
Published: June 2021

As is known, wind is a renewable and non-polluting energy resource. In addition, there is no transportation problem in wind energy and it does not require very high technology for electricity generation. Wind turbines are used for electricity generation from kinetic energy of wind. In the point of power curves of these turbines, wind speed must be a certain band. Generally, they do not generate electricity cut-in wind speed that is between 0 and 4 m/s and cut out wind speed that is over 20-25 m/s. Over cut-out values cause breaking down of wind turbines, because high wind speeds create extra mechanical loads on them. Therefore, maximum/extreme winds and their estimation and prediction carry weight in terms of energy generation.

New European Wind Atlas (NEWA) is the project, within the scope of ERANET+ Program, and the attendants are Belgium, Denmark, Germany, Latvia, Portugal, Spain, Sweden, and Turkey. The aim of NEWA is to present a new wind atlas to the wind industry. In this project, the physical model used for obtaining wind speeds is a numerical weather prediction model named Weather Research and Forecasting (WRF).

One of the methods, which are developed by imitating of biological properties of living forms in a virtual environment, is Artificial Neural Networks (ANNs). Stimulations taken from the environment by using sense organs are transmitted to brain whereby neurons in a body and brain makes a decision towards these stimulations. That is the working form of ANNs. Moreover, ANNs can be thought as a black box, which processes given data and produces outputs against inputs. Furthermore, they are a method of Artificial Intelligence.

In this study, maximum wind speeds of 4 different wind farms in Turkey were estimated by using a downscaling method based on ANNs and wind data which were produced in grid points of NEWA Project. Besides that, 8 different levels (10, 50, 75, 100, 150, 200, 250, and 500 m) for each wind farm were considered. As a result of determining the best ANN architectures with sensitivity analysis, it was seen that Levenberg-Marquardt Backpropagation (trainlm) approach as a training algorithm and 9 neurons in each layer are common traits of best ANN architectures. In addition, 50 m for 2 wind farms and 10 m with 75 m for others were determined as an optimum downscaling levels. Moreover, according to downscaling results, correlation values were calculated around 0.80.

Key Words: ANN, Downscaling, Maximum wind, NEWA, Turkey, Wind farm.
Operational aspects of machine learning in a met-service
Authors: Liniger Mark A. , Cattani Daniel , Crouzy Benoit , Nerini Daniele , Moret Lionel , Sigg Christian
Published: June 2021

Machine Learning has a big potential for various tasks along the whole value chain of a national Met-Service. Indeed, many research groups, private and national weather services have started to explore the possibilities and first real-time operational implementations are in place already. However, the building up of the expertise is difficult, large amounts of data have to be made available in an efficient way and the necessary tools have special and demanding requirements concerning infrastructure and maintenance. Also, the transition from research results towards operational tools being operated in realtime is a particular challenge. Not least, trust from end-users must be built, while trying to avoid falling into the short-term hype trap.

In this presentation, we want to present some examples of machine-learning at MeteoSwiss that are in operational use or soon to be. This includes the use in a measurement system to identify pollen species, the quality control of meteorological observations, the postprocessing of numerical weather forecasts and the condensation of weather forecast information for the meteorologists. These examples have different characteristics and cover a wide range of applications, but also share some common properties. We want to juxtapose these properties with the incentives and conditions how machine learning methods are developed and employed in a more research oriented context like in academia. It turns out that an operational setup of machine learning has very different requirements than machine learning in a research context. The identification of these differences, but also the similarities, could help to understand the challenge of bringing research results into operation and how to alleviate this challenge in the future.