bluuebunny/crossref_metadata_2025 huggingface dataset:
The adoption of digital administrative systems and practices at Ezemvelo KwaZulu-Natal (KZN) Wildlife
Authors:   , Ndlovu Philisiwe Yvonne
Published: January 2024

This study examines adoption and usage of digital administrative systems and practices at Ezemvelo KZN Wildlife (EKZNW) in order to suggest strategies for better utilisation of digital administrative systems and practices at Ezemvelo KZN Wildlife. This study will therefore attempt to improve focus on the administrative employees’ adoption and usage of implemented digital systems and practices, to improve organisational productivity. The researcher adopted a quantitative approach using online survey to collect data. Data were analysed using a Statistical Package for Social Sciences (SPSS) version 25.0. Target respondents were 160 administrative employees at Ezemvelo KZN Wildlife, as they are directly involved in the adoption and usage of digital administrative systems and practices. The researcher adopted a census of all 160 administrative employees in order to achieve the objectives of the study. This study revealed that even though the digital administrative systems at Ezemvelo KZN Wildlife are adopted to a certain extent. Employees do not wholly adopt them. They mainly prioritise those systems related to their personal information, followed by those related to communicating and conducting meetings. Off concern, is the lack of training provided to employees as one of the factors inhibiting the adoption of digital administrative systems and practices. The study concludes that, it is highly critical that there is more focus placed on the adoption of digital administrative systems and practices. Furthermore, attention should be paid to factors of organisational and individual influence, that have been found in the study to impede the adoption of digital administrative systems and practices aimed at enhancing the productivity and efficiency in the administrative operations at Ezemvelo KZN Wildlife. This study argues that management needs to enhance communication to employees regarding the purpose and benefits of the digital administrative systems and practices to be used and adopted. In addition, management at Ezemvelo KZN Wildlife should prioritise investing in connectivity, as it plays a crucial role in the adoption and usage of digital administrative systems and practices. It is further recommended that management should ensure that the information related to digital administrative systems and practices is easily accessible on the EKZNW website. This will help boost employee productivity and quality customer satisfaction post Covid-19 pandemic.
Up Against the Law
Authors: Falciola Luca
Published: January 2024

As protest movements took to the streets during the 1960s and 1970s, a group of lawyers joined forces with America’s most confrontational activists. In pursuit of radical change themselves, these militant attorneys went beyond providing mere representation. They identified with their clients, defied the habits of a conservative profession, and formulated a corrosive critique of the legal system, questioning the neutrality and transformative power of law. While exploiting the courtrooms as political forums, they developed aggressive litigation strategies and became involved with the organization of protest. Drawing on extensive archival research and interviews, historian Luca Falciola reconstructs this largely unmapped phenomenon and challenges the reader to think anew about the pivotal role of lawyers in social movements. At the heart of this book is the story of the National Lawyers Guild. Founded in 1937, the Guild represented the first integrated and progressive bar association of America. The Guild returned to prominence in the early 1960s, at the vanguard providing legal aid to civil rights workers in the South. Since then, leftist students, disobedient soldiers, rebellious inmates, radical minorities, and revolutionary groups such as the Black Panther Party and the Weather Underground have relied on this cadre of sympathetic lawyers to defend and empower them.
Administering Freedom
Authors: Kretz Dale
Published: January 2024

This book offers the definitive history of how formerly enslaved men and women pursued federal benefits from the Civil War to the New Deal and, in the process, transformed themselves from a stateless people into documented citizens. As claimants, Black southerners engaged an array of federal agencies. Their encounters with the more familiar Freedmen's Bureau and Pension Bureau are presented here in a striking new light, while their struggles with the long-forgotten Freedmen's Branch appear in this study for the very first time. Based on extensive archival research in rarely used collections, Dale Kretz uncovers surprising stories of political mobilization among tens of thousands of Black claimants for military bounties, back payments, and pensions, finding victories in an unlikely place: the federal bureaucracy. As newly freed, rights-bearing citizens, they negotiated issues of slavery, identity, family, loyalty, dependency, and disability, all within an increasingly complex and rapidly expanding federal administrative state—at once a lifeline to countless Black families and a mainline to a new liberal order.
The Struggle for Iran
Authors: Painter David S. , Brew Gregory
Published: January 2024

Beginning with the nationalization of the Iranian oil industry in spring 1951 and ending with its reversal following the overthrow of Prime Minister Mohammad Mosaddeq in August 1953, the Iranian oil crisis was a crucial turning point in the global Cold War. The nationalization challenged Great Britain's preeminence in the Middle East and threatened Western oil concessions everywhere. Fearing the loss of Iran and possibly the entire Middle East and its oil to communist control, the United States and Great Britain played a key role in the ouster of Mosaddeq, a constitutional nationalist opposed to communism and Western imperialism. US intervention helped entrench monarchical power, and the reversal of Iran's nationalization confirmed the dominance of Western corporations over the resources of the Global South for the next twenty years. Drawing on years of research in American, British, and Iranian sources, David S. Painter and Gregory Brew provide a concise and accessible account of Cold War competition, Anglo-American imperialism, covert intervention, the political economy of global oil, and Iran's struggle against autocratic government. The Struggle for Iran dispels myths and misconceptions that have hindered understanding this pivotal chapter in the history of the post–World War II world.
PERANCANGAN DESAIN ANTARMUKA APLIKASI PEMBELAJARAN ONLINE BERBASIS MOBILE MENGGUNAKAN METODE DESIGN THINKING
Authors: Hidayat Akik , Fauziyyah Hana Meilina
Published: January 2024

Aplikasi pembelajaran online sangat dibutuhkan oleh masyarakat yang ingin belajar. Banyak aplikasi pembelajaran online yang tidak memperhatikan tampilan, sehingga banyak yang tidak tertarik dengan aplikasinya. Salah satu metode untuk membuat tampilan adalah menggunakan Design Thinking. Design thinking juga merupakan sebuah framework atau model cara berpikir kreatif untuk memecahkan permasalahan yang dihadapi dan berfokus pada pengguna. Terdapat 5 tahap yang memungkinkan untuk memperoleh keluaran yang inovatif.

 

Kata Kunci— Pembelajaran online, desain antarmuka, user experience
El despertar de la serpiente. La minería en la Sierra Madre de Chiapas
Authors: Roblero-Morales Marín , Hernández-Aguilar Gerardo Porfirio
Published: January 2024

Esta investigación analiza el proceso de la minería en el estado de Chiapas como fenómeno social nuevo, además de sus consecuencias que se observan en el deterioro del territorio. Describe los problemas socioambientales causados por la extracción minera de la empresa canadiense Blackfire en el municipio de Chicomuselo, donde ofreció generar desarrollo sustentable, empleos y bienestar económico a las comunidades.Las condiciones de marginación, pobreza, desempleo y devastación ocasionadas por los recientes huracanes facilitaron el acceso de la empresa. Los efectos destructivos de la minería polarizaron a la sociedad y fueron percibidos como factores de riesgo socioambiental que motivaron el surgimiento de la resistencia antiminera (respuesta comunitaria), la cual tuvo como ejes la identidad maya y la relación humano-naturaleza, reacción que fue criminalizada.Este proceso tuvo como sustento teórico los nuevos movimientos sociales de la acción colectiva, el concepto de territorio e identidad.
Hadži Gazi-beg Čengić medresa u Višegradu
Authors: Duranović Elvir
Published: January 2024

U uvodnom dijelu ovog teksta autor donosi pregled objavljene literature o Višegradskoj medresi i metodologiju rada koja se temelji na tekstualnoj analizi neobjavljene arhivske građe. Autor potom govori o Višegradskoj medresi, njenom osnivaču i vakufima iz čijih sredstava se finansirao njen rad. Na osnovu sačuvanih dokumenata o Hadži Gazi-beg Čengić medresi iz Arhiva Gazi Husrev-begove biblio­teke, autor u nastavku predstavlja biografije trojice poznatih muderisa ove medrese, analizira njen nastavni plan i donosi zbirne podatke o učenicima medrese u periodu od 1897. do 1925. godine, uz predstavljanje određenih informacija iz životopisa nekih njenih đaka. Hadži Gazi-beg Čengić medresa je odgojno-obrazovna ustanova čiji značaj za islamsko vjersko prosvjećivanje Bošnjaka muslimana na području Višegrada i okoline, imajući u vidu da je o njoj do sada objavljena samo jedna kraća istraživačka bilješka, nije dovoljno istaknut. Obilje novih, do sada neobjavljenih informacija o ovoj medresi, koje autor donosi u radu, pomoći će da se njena važnost za očuvanje islama na području Višegrada i šire sagledava u novom svjetlu.
Traktat o akuzativu stanja Mustafe Muhibbija
Authors: Mulović Amra
Published: January 2024

U ovom radu predstavljen je do sada neobrađen traktat o akuzativu stanja (Risāla ḥāl) napisan krajem 18. stoljeća na arapskom jeziku. Autor traktata je Mustafa Muhibbi (Muṣṭafā Muḥibbī), koji se spominje kao zvornički muftija, pjesnik i prozni autor. Kao izvori korištena su dva rukopisa traktata, od kojih se jedan čuva u rukopisnoj zbirci Nacionalne i univerzitetske biblioteke Bosne i Hercegovine u Sarajevu, a drugi u zbirci rukopisa na orijentalnim jezicima Univerzitetske biblioteke „Svetozar Marković” u Beogradu. Istraživanje u ovom radu obuhvata tekstološku analizu dvaju dostupnih rukopisa, kritičku obradu djela, prijevod i tekstualnu analizu sadržaja traktata. Pregled sadržaja djela donosi studiju o akuzativu stanja u okviru arapske gramatičke misli, a posebno u okviru onih klasičnih izvora na koje se autor poziva razmatrajući centralno pitanje traktata posvećeno različitim jezičkim tumačenjima 28. ajeta sure Sabaʼ.
Idiomske skupine u Mevludu Vehbije Hodžića. Utjecaj forme mevluda na sastav idiomskih skupina
Authors: Hodžić-Čavkić Azra
Published: January 2024

Tradicija pisanja mevluda na bosanskom jeziku duga je više od stoljeća, ali je mevlud kao književni žanr najčešće ostao van okvira razmatranja filoloških istraživanja. To vrijedi i za frazeološka istraživanja, jer niti jedan mevlud nije bio izvorom za frazeološku građu konsultiranim rječnicima, što je dodatni signal da se lingvistička istraživanja posvete ovom književnom obliku u bosanskom jeziku. Mevlud kao takav posjeduje značajan broj idiomskih skupina iz razloga što izražava autentičnu sliku svijeta iskazanu vrijednosnim sudovima kolektiva, a sam mevlud baštini vrijednosni sud kolektiva s obzirom na temu koju obrađuje. Budući da forma mevluda ima svoja ograničenja jer je pisan u stihu, takva strukturalna odlika utjecala je na sastav i upotrebu idiomskih skupina. Stoga se ovaj rad bavi Hodžićevim Mevludom te ispituje u kakvom su odnosu njegov jedanaesterački stih i sastav idiomskih skupina. Analizirana građa potvrđuje da je odabrani mevlud bogat izvor frazeološke slike svijeta, ali i to da je autor svjesnim intervencijama utjecao na sastav dvije trećine upotrijebljenih idiomskih skupina. Te dvije trećine grupirane su prema vrsti intervencije na varijante idiomskih skupina i okazionalizme idiomskih skupina prema načinu na koji se intervenira, tj. prema dubini autorske korekcije osnovne slike idiomskih skupina iz uzualnih oblika zabilježenih u rječnicima.
Ahmed Smajlović o orijentalističkoj recepciji arapske književnosti
Authors: Horozović Nejira
Published: January 2024

Dio doktorske disertacije Ahmeda Smajlovića Filozofija orijentalizma i njen utjecaj na savremenu arapsku književnost čini kritičku obradu određenih orijentalista koji su radili i djelovali s početka pa do sredine 20. stoljeća. Ovaj rad, nakon uvodnih crtica o promjenama u recepciji Orijenta na Zapadu početkom 20. stoljeća, donosi pitanja koja Smajlović nastoji obraditi u svojoj analizi orijentalista i njihovih djela o arapskoj književnosti. Smajlović u fokus stavlja sljedeće orijentaliste: Brockelmanna, Nallina, Nicholsona, Blachèrea, Gibba, Kračkovskog, von Grunebauma, Palenciju i Adamsa. U radu se donosi osvrt na Smajlovićevu metodologiju u predstavljanju tih orijentalista ponaosob i njihovih ključnih stavova, te se ukazuje na prednosti i nedostatke te Smajlovićeve metodologije.
Transistors à effet de champ basés sur des matériaux 2D : perspective de modélisation
Authors: LUISIER Mathieu , KLINKERT Cedric , FIORE Sara , BACKMAN Jonathan , LEE Youseung , STIEGER Christian , SZABÓ Áron
Published: January 2024

Le potentiel des matériaux 2D pour des applications dans les transistors à effet de champ présenté sur la base de simulations de transport quantique d’électrons basés sur la théorie de la fonctionnelle de la densité, les fonctions localisées de Wannier et la fonction de Green hors équilibre. Il en résulte un aperçu détaillé et des perspectives claires.
Transistors à effet de champ à capacité négative
Authors: CAO Wei , BANERJEE Kaustav
Published: January 2024

Le FET à capacité négative est prometteur grâce à la diminution de sa tension d'alimentation. Cependant, l'authenticité de la capacité négative dans différentes conditions d'essai reste controversée. Après l'introduction de ses principes fondamentaux, ce chapitre se concentre sur les défis et opportunités du point de vue de la physique des dispositifs, et présente un aperçu des progrès expérimentaux.
Z2FET à zéro ionisation par impact et zéro pente sous le seuil
Authors: LACORD Joris
Published: January 2024

Le Z2FET est un transistor à effet de champ avec « zéro » pente sous le seuil et « zéro » impact ionisation, basé sur une diode partiellement couverte par la grille et polarisée en direct sur silicium sur oxyde. Ce chapitre présente son fonctionnement, sa modélisation, les preuves expérimentales ainsi que la DRAM, les optimisations et d'autres applications potentielles.
Les régions de sécurité : un monde hétérogène entre conflits et coopérations
Authors: CHAUVIN Emmanuel
Published: January 2024

Ce chapitre est orienté vers les enjeux sécuritaires transfrontaliers, une composante essentielle des régions d’aujourd’hui. Il analyse la construction régionale de la sécurité et la concentration régionale de l’insécurité. Dans les deux cas, il faut considérer l’échelle régionale avec finesse : les architectures régionales de sécurité ont souvent une taille macrorégionale, alors que la géographie de la violence se concentre souvent dans des agrégats plus petits de pays voisins.
Technical note: Emulation of a large-eddy simulator for stratocumulus clouds in a general circulation model
Authors: Nordling Kalle , Keskinen Jukka-Pekka , Romakkaniemi Sami , Kokkola Harri , Räisänen Petri , Lipponen Antti , Partanen Antti-Ilari , Ahola Jaakko , Tonttila Juha , Alper Muzaffer Ege , Korhonen Hannele , Raatikainen Tomi
Published: January 2024

Abstract. Here we present for the first time a proof of concept for an emulation-based method that uses a large-eddy simulations (LESs) to present sub-grid cloud processes in a general circulation model (GCM). We focus on two key variables affecting the properties of shallow marine clouds: updraft velocity and precipitation formation. The LES is able to describe these processes with high resolution accounting for the realistic variability in cloud properties. We show that the selected emulation method is able to represent the LES outcome with relatively good accuracy and that the updraft velocity and precipitation emulators can be coupled with the GCM practically without increasing the computational costs. We also show that the emulators influence the climate simulated by the GCM but do not consistently improve or worsen the agreement with observations on cloud-related properties, although especially the updraft velocity at cloud base is better captured. A more quantitative evaluation of the emulator impacts against observations would, however, have required model re-tuning, which is a significant task and thus could not be included in this proof-of-concept study. All in all, the approach introduced here is a promising candidate for representing detailed cloud- and aerosol-related sub-grid processes in GCMs. Further development work together with increasing computing capacity can be expected to improve the accuracy and the applicability of the approach in climate simulations.
Air-sea interactions in stable atmospheric conditions: Lessons from the desert semi-enclosed Gulf of Eilat (Aqaba)
Authors: Abir Shai , McGowan Hamish A. , Shaked Yonatan , Gildor Hezi , Morin Efrat , Lensky Nadav G.
Published: January 2024

Abstract. Accurately quantifying air-sea heat and gas exchange is crucial for comprehending thermoregulation processes and modeling ocean dynamics; these models incorporate bulk formulae for air-sea exchange derived in unstable atmospheric conditions. Therefore, their applicability in stable atmospheric conditions, such as desert-enclosed basins in the Gulf of Eilat/Aqaba (coral refugium), Red Sea, and Persian Gulf, is unclear. We present 2-year Eddy Covariance results from the Gulf of Eilat, a natural laboratory for studying air-sea interactions in stable atmospheric conditions which are directly related to ocean dynamics. The measured mean evaporation, 3.22 m year-1, approximately double than previously estimated by bulk formulae, is exceeding the heat flux provided by radiation. Notably, in arid environments wind speed seasonal trend is compelling maximum evaporation in summer, with minimum winter rate. The higher evaporation rate appears when elevated wind, particularly in the afternoon, coincide with an increase in vapor pressure difference. The bulk formulae approach inability to capture the seasonal (opposite from our measurements) and annual trend of evaporation is linked to errors in quantifying of the atmospheric boundary layer stability parameter. Most of the year, there is a net cooling effect of surface water (-79 W m-2), primarily through evaporation. The substantial heat deficit is compensated by the advection of heat via northbound currents from the Red Sea, which we indirectly quantify from energy balance considerations. Cold and dry synoptic-scale winds induce extreme heat loss through air-sea fluxes, and are correlated with destabilizing of the water column during winter and initiating vertical water column mixing.
Implementing detailed nucleation predictions in the Earth system model EC-Earth3.3.4: sulfuric acid-ammonia nucleation
Authors: Svenhag Carl , Sporre Moa Kristina , Olenius Tinja , Yazgi Daniel , Blichner Sara Marie , Nieradzik Lars Peter , Roldin Pontus
Published: January 2024

Abstract. Representing detailed atmospheric aerosol processes in global Earth system models (ESMs) has proven challenging both from a computational and a parameterization perspective. The representation of secondary organic aerosol (SOA) formation and new particle formation (NPF) in large ESMs are generally constructed with low detail to save computational costs. The simplification could result in losing the representation of some processes. In this study, we test and evaluate a new approach for improving the description of NPF processes in the ESM EC-Earth3 (ECE3) without loss of significant computational time. The current NPF scheme in EC-Earth3 is derived from the nucleation of low-volatility organic vapors and sulfuric acid (H2SO4) together with a homogeneous water-H2SO4 nucleation scheme. We expand the existing schemes and introduce a new look-up table approach that incorporates detailed formation rate predictions by molecular modeling of sulfuric acid-ammonia nucleation (H2SO4-NH3). We apply tables of particle formation rates for H2SO4-NH3 nucleation, including dependence on temperature, atmospheric ion production rate, and molecular cluster scavenging sink. The resulting differences between using the H2SO4-NH3 nucleation in ECE3 and the original default ECE3 scheme are evaluated and compared with a focus on changes in aerosol composition, cloud properties, and radiation balance. From this new nucleation scheme, EC-Earth3’s global average aerosol concentrations in the sub-100 nm sizes increased by 12–28 %. Aerosol concentrations above 100 nm and the direct radiative effect (in Wm−2) from the changed nucleation only resulted in minor changes. However, the radiative effect from clouds affected by aerosols from the new nucleation scheme resulted in a global decrease (cooling effect) by 0.28–1 Wm−2. Additionally, several stations with observed aerosol size number distribution measurements are compared with the model results to examine the performance of the NPF schemes.
Optimizing the terrestrial ecosystem gross primary productivity using carbonyl sulfide (COS) within a “two-leaf” modeling framework
Authors: Zhu Huajie , Xing Xiuli , Wu Mousong , Ju Weimin , Jiang Fei
Published: January 2024

Abstract. Accurately modeling gross primary productivity (GPP) is of great importance in diagnosing terrestrial carbon-climate feedbacks. Process-based terrestrial ecosystem models are often subject to substantial uncertainties, primarily attributed to inadequately calibrated parameters. Recent attention has identified carbonyl sulfide (COS) as a promising proxy of GPP, due to the close linkage between leaf exchange of COS and carbon dioxide (CO2) through their shared pathway of stomatal diffusion. However, most of the current modeling approaches for COS and CO2 did not explicitly consider the vegetation structural impacts, i.e. the differences between the sun-shade and sunlit leaves in COS uptake. This study used ecosystem COS fluxes data from 7 sites to optimize GPP estimation across various ecosystems with the Boreal Ecosystem Productivity Simulator (BEPS), which was further developed for simulating the leaf COS uptake under its state-of-the-art ‘two-leaf’ framework. Our results demonstrated the substantial improvement in GPP simulation across various ecosystems through the fusion of COS data into the ‘two-leaf’ model, with the ensemble mean of root mean square error (RMSE) for simulated GPP reduced by 18.99 % to 66.64 %. Notably, we also shed light on the remarkable identifiability of key parameters within the BEPS model, including the maximum carboxylation rate of Rubisco at 25 °C (Vcmax25), minimum stomatal conductance (bH2O), and leaf nitrogen content (Nleaf), despite intricate interactions among COS-related parameters. Furthermore, our global sensitivity analysis delineated both shared and disparate sensitivities of COS and GPP to model parameters and suggested the unique treatment of parameters for each site in COS and GPP modeling. In summary, our study deepened insights into the sensitivity, identifiability, and interactions of parameters related to COS, and showcased the efficacy of COS in reducing uncertainty in GPP simulations.
Dynamic interaction of lakes, climate and vegetation over northern Africa during the mid-Holocene
Authors: Specht Nora Farina , Claussen Martin , Kleinen Thomas
Published: January 2024

Abstract. During the early to mid-Holocene, about 11,500 to 5,500 years ago, lakes expanded across the Sahel and Sahara in response to enhanced summer monsoon precipitation. To investigate the effect of these lakes on the West African summer monsoon, previous simulation studies prescribed mid-Holocene lakes from reconstructions. By prescribing mid-Holocene lakes, however, the terrestrial water balance is inconsistent with the size of the lakes. In order to close the terrestrial water cycle, we construct a dynamic endorheic lake (DEL) model and implement it into the atmosphere-land model ICON-JSBACH4. For the first time, this allows us to investigate the dynamic interaction between climate, lakes and vegetation over northern Africa. Additionally, we investigate the effect of lake depth changes on the mid-Holocene precipitation, which was neglected in previous simulation studies. A pre-industrial control simulation shows that the DEL model realistically simulates the lake extent over northern Africa. Only in the Ahnet and Chotts Basin is the lake area slightly overestimated, which likely relates to the coarse resolution of the simulations. The mid-Holocene simulations reveal that both, the lake expansion and the vegetation expansion cause a precipitation increase over northern Africa. The sum of these individual contributions on the precipitation is however larger than the combined effect, when lake and vegetation dynamics interact. Thus, the lake-vegetation interaction causes a relative drying response over the entire Sahel. The main reason for this drying response is that the simulated vegetation expansion cools the land surface more strongly than the lake expansion, mainly the expansion of the Lake Chad area. The resulting warming response over the larger lake area causes local changes in meridional surface-temperature gradient that decelerate the inland moisture transport from the tropical Atlantic into the Sahel, which causes a drying response in the Sahel. An idealized mid-Holocene experiment shows that a similar drying response is induced when the depth of Lake Chad is decreased by about 1–5 m, without changing the horizontal lake area. By reducing the depth of Lake Chad the heat storage capacity of the lake decreases and the lakes warms faster during the summer months. Thus, in the ICON-JSBACH4 model, the lake depth significantly influences the simulated surface temperature and the simulated meridonal surface-temperature gradient between the simulated lakes and vegetation and thus, the mid-Holocene precipitation over northern Africa.
The oxygen deficiency index blueprint allows an economic and quick scan via baseline assessment for forecasting the risk of seasonal oxygen deficiency in the North and Baltic Seas
Authors: Marki Alexandra , Li Xin , Jandt-Scheelke Simon
Published: January 2024

Abstract. Oxygen deficiency zones (ODZs) in coastal seas can become hazardous to organisms and may have severe ecological and economic consequences for the environment, the fisheries, and the tourism industries. A tight interaction between ventilation and respiration governs marine oxygen levels. Regions with high primary production and a thin water column below the seasonal mixed layer are particularly prone to the formation of oxygen deficiency. In the study of Große et al. (2016) the critical parameters of the oxygen deficiency index (ODI) were identified as stratification and primary production during the formation of oxygen deficiency in the seasonally stratified regions of the North Sea. In order to approach realistic spatio-temporal distributions of ODZs, Große et al. (2016) formulated a depth index serving as a proxy for the thickness of the water column below the mixed layer depth (MLD). Here we propose the further developed ODI to represent two differing hydrographic regimes, the North and the Baltic Seas, by using a density-based criterion of the MLD and the vertical extension of the water column between the seafloor and the bottom layer of the MLD. Moreover, we define the stratification status of the water column using continuous stratification periods of 30 days as our reference period for higher risks of developing ODZs. Different to Große et al. (2016), net primary production is not cumulated over the entire growing season but only over this reference period. With these modifications, the revised ODI offers intuitive, short-term forecasts on the areas at risk of developing oxygen deficiency in high spatio-temporal resolution for the coastal zone of the North and Baltic Seas. This allows an operational forecasting of ODZs to inform responsible authorities and civil services in advance. We propose an economic solution to assess oxygen conditions of the past, the present and test for the risk to developing ODZs in the near future. We are able to run all necessary simulations and calculations for this research on a simple laptop. We mostly used free and open software products and Open Data products. Our data set up consists of: a) Free available netCDF output files of the operational HBM-ERGOM model and b) free available data from the MARNET monitoring network, both operated by the Federal Maritime and Hydrographic Agency (BSH).
Understanding Absorption by Black Versus Brown Carbon in Biomass Burning Plumes from the WE-CAN Campaign
Authors: Shen Yingjie , Pokhrel Rudra P. , Sullivan Amy P. , Levin Ezra J. T. , Garofalo Lauren A. , Farmer Delphine K. , Permar Wade , Hu Lu , Toohey Darin W. , Campos Teresa , Fischer Emily V. , Murphy Shane M.
Published: January 2024

Abstract. Aerosol absorption of visible light has an important impact on global radiative forcing. Wildfires are one of the major sources of light-absorbing aerosol, but there remains significant uncertainty about the magnitude, wavelength dependence and bleaching of absorption from biomass burning aerosol. We collected and analyzed data from 21 Western United States wildfire smoke plumes during the 2018 WE-CAN airborne measurement campaign to determine the contribution of black carbon (BC), brown carbon (BrC), and lensing to the aerosol mass absorption cross-section (MAC). MACBC, MAC of organics (MACBrC+lensing), and the MAC of water-soluble BrC (MACws_BrC660) are calculated using Photoacoustic Absorption Spectrometer, Single Particle Soot Photometer and Particle-into-Liquid Sampler measurements. MACBC660 does not change significantly with physical age, organic aerosol (OA) concentration, oxygen to carbon ratio (O:C), gas-phase toluene:benzene ratio, modified combustion efficiency (MCE), altitude, or temperature, and has a relatively stable average value of 10.9 ± 2.1 m2 g-1. On average, 54 % of non-BC absorption (23 % total absorption) at 660 nm is from water-soluble BrC. MACws_BrC660 is 0.06 ± 0.04 m2 g-1 while MACBrC+lensing is 0.11 ± 0.06 m2 g-1 at 660 nm, increasing to 0.59 ± 0.19 m2 g-1 at 405 nm. MACBrC+lensing is constant with physical age and MCE, but increases slightly with increasing O:C or decreasing toluene:benzene, while total absorption (normalized to CO) slightly decreases with increasing O:C or decreasing toluene:benzene due to decreasing OA. No evidence of BrC bleaching is observed. Comparison to commonly used parameterizations, modeling studies, and the FIREX-AQ observations suggest model overestimation of absorption is likely due to incorrect BrC refractive indices. Quantification of significant brown carbon in the red wavelengths and the stability of MACBC, the observation of minimal bleaching, and the observation of changes in OA with O:C and toluene:benzene markers all serve as important constraints on aerosol absorption in regional and global climate models.
Investigating long-term changes in polar stratospheric clouds above Antarctica: A temperature-based approach using spaceborne lidar detections
Authors: Leroux Mathilde , Noel Vincent
Published: January 2024

Abstract. Polar stratospheric clouds play a significant role in the seasonal thinning of the ozone layer by facilitating the activation of stable chlorine and bromine reservoirs into reactive radicals, as well as prolonging the ozone depletion by removing HNO3 and H2O of the stratosphere by sedimentation. In a context of climate change, the cooling of the lower polar stratosphere could enhance the PSC formation and by consequence cause more ozone depletion. There is thus a need to document the evolution of the PSC cover to better understand its impact on the ozone layer. In this article we present a statistical model based on the analysis of the CALIPSO PSC product from 2006 to 2020. The model predicts the daily regionally-averaged PSC density by pressure level derived from stratospheric temperatures. Applying our model to stratospheric temperatures from the CALIPSO PSC product over the 2006–2020 period shows it is robust in the stratosphere between 10 and 150 hPa, reproducing well PSC variations over daily timescales and seasonal differences (2006–2020). The model reproduces well the PSC seasonal progression, even during disruptive events like stratospheric sudden warmings, except for years characterized by volcanic eruptions. We apply our model to gridded stratospheric temperatures from reanalyses over the complete south pole domain to evaluate changes in PSC seasons over the 1980–2021 period. We find two distinct periods in the evolution of the PSC season duration. Between 1980 and 2000, the PSC season increased by 15 days at 10–20 hPa with an increasing lengthening as we descend in altitudes to reach 30 days at 100–150 hPa. This lengthening is in possible relation with major eruptions occurring over this period. After 2000, a temporary drop mostly visible at high (10–20 hPa) and lower altitude (100–150 hPa) is followed by a progressive increase in PSC season duration. Over the 1980–2020 period, the PSC season increased by 20 days between 30–100 hPa. These changes are altitude-dependent and statistically significant. We discuss the impact of non-temperature stratospheric changes on the variations of PSC seasons.
Probing Iceland's Dust-Emitting Sediments: Particle Size Distribution, Mineralogy, Cohesion, Fe Mode of Occurrence, and Reflectance Spectra Signatures
Authors: González-Romero Adolfo , González-Flórez Cristina , Panta Agnesh , Yus-Díez Jesús , Córdoba Patricia , Alastuey Andres , Moreno Natalia , Kandler Konrad , Klose Martina , Clark Roger N. , Ehlmann Bethany L. , Greenberger Rebecca N. , Keebler Abigail M. , Brodrick Phil , Green Robert O. , Querol Xavier , Pérez García-Pando Carlos
Published: January 2024

Abstract. Characterizing physico-chemical properties of dust-emitting sediments in arid regions is fundamental to understand the effect of dust on climate and ecosystems. For high-latitude dust (HLD), this knowledge is scarce. This study focuses on the particle size distribution (PSD), mineralogy, cohesion, iron (Fe) mode of occurrence and Visible Near Infra-Red (VNIR) reflectance spectra of dust-emitting sediments from dust-hotspots in Iceland (HLD region). Extensive analysis was conducted on top sediments collected from seven dust-sources and an intensive at Jokulsá basin including top sediments, sediments and aeolian ripples. Fully and minimally dispersed PSDs evidenced remarkable similarities with an average median diameter of 56±69 and 55±62 µm. Mineralogical analyses showed the prevalence of amorphous phases (68±26 %), feldspars (17±13 %), and pyroxenes (9.3±7.2 %), aligned with the reflectance spectra. Fe content reached 9.5±0.40 wt %, mainly in silicate structures (80±6.3 %), complemented by magnetite (16±5.5 %), hematite/goethite (4.5±2.7 %), and readily exchangeable Fe-ions or Fe nano-oxides (1.6±0.63 %). Icelandic top sediments have coarser PSD compared to the high dust-emitting crusts from mid-latitude arid regions, distinctive mineralogy, and threefold bulk Fe content, with a large presence of magnetite. The congruence between fully and minimally dispersed PSDs underscores a reduced particle aggregation and cohesion of Icelandic top sediments, suggesting that aerodynamic entrainment of dust may also play a role upon emission in this region, aside of saltation bombardment. The analysis of an extensive sampling in Dyngjusandur allowed this study to present a conceptual model to encapsulate Iceland's rapidly evolving high dust-emitting environments.
Global scenarios of anthropogenic mercury emissions
Authors: Brocza Flora Maria , Rafaj Peter , Sander Robert , Wagner Fabian , Jones Jenny M.
Published: January 2024

Abstract. Anthropogenic mercury (Hg) emissions to the atmosphere are a long-lived hazard to human and environmental health. The UN Minamata Convention on Mercury is seeking to lower anthropogenic mercury emissions through a mix of policies from banning Hg uses and trade, to reducing unintentional Hg releases from different activities. In addition to independent Hg policy, greenhouse gas, particulate matter (PM) and SO2 reduction policies may also lower Hg emissions as a co-benefit. This study uses the Greenhouse Gas – Air Pollution Interactions and Synergies (GAINS) model to examine the effect of different clean air and climate policy on future global Hg emissions. The Baseline scenario assumes current energy use and Hg emissions, as well as current legislation for clean air, mercury and climate policy. In addition, we explore the impact of the Minamata Convention, co-benefits of climate policies and of stringent air pollution policies, as well as a maximum feasible reduction scenario for Hg (Hg-MFR). Hg emission projections until 2050 show noticeable reductions in combustion sectors for all scenarios, due to a decrease in global fossil fuels and traditional biomass use, leading to emission reductions of 33 % (Baseline) up to 90 % when combining stringent climate and Hg-MFR. Cement and non-ferrous metal emissions increase in all activity scenarios with current air pollution policy, but can be reduced by up to 72 % and 46 % respectively in 2050 with stringent Hg-specific measures. Other emissions (including waste) are a large source of uncertainty in this study, and projections range between a 22 % increase and 54 % decrease in 2050 depending on both climate and clean air policy. The largest absolute reduction potential for Hg abatement, but also the largest uncertainties of absolute emissions lie in the in small-scale and artisanal gold production, where Hg-specific abatement measures could eliminate annual Hg emissions in the range of 601–1371 t (95 % confidence interval). 90 % of the Hg emissions in GAINS are covered by the Minamata Convention. Overall, the findings emphasize the necessity of implementing targeted Hg control policies in addition to stringent climate, PM and SO2 policies to achieve significant reductions in Hg emissions.
Secondary Organic Aerosols Derived from Intermediate Volatility n-Alkanes Adopt Low Viscous Phase State
Authors: Galeazzo Tommaso , Aumont Bernard , Camredon Marie , Valorso Richard , Lim Yong B. , Ziemann Paul J. , Shiraiwa Manabu
Published: January 2024

Abstract. Secondary organic aerosol (SOA) derived from n-alkanes, as emitted from vehicles and volatile chemical products, is a dominant component of anthropogenic particulate matter, yet its chemical composition and phase state are poorly understood and hardly constrained in aerosol models. Here we provide a comprehensive analysis of n-alkane SOA by explicit chemistry modeling, machine learning, and laboratory experiments to show that, counterintuitively, n-alkane SOA adopt low viscous semisolid or liquid states. Our study underlines the complex interplay of molecular composition and SOA viscosity: n-alkane SOA with higher carbon number mostly consists of less functionalized first-generation products with lower viscosity, while the lower carbon number SOA contains more functionalized multigeneration products with higher viscosity. This study opens up a new avenue for analysis of SOA processes and the results indicate little kinetic limitations of mass accommodation in SOA formation, supporting the application of equilibrium partitioning for simulating n-alkane SOA formation in large-scale atmospheric models.
Climatology and Trends in Concurrent Temperature Extremes in the Global Extratropics
Authors: Messori Gabriele , Segalini Antonio , Ramos Alexandre M.
Published: January 2024

Abstract. Simultaneous occurrences of multiple heatwaves or cold spells in remote geographical regions have drawn considerable attention in the literature, due to their potentially far-reaching impacts. We introduce a flexible toolbox to study such concurrent temperature extremes, with adjustable parameters that different users can tailor to their specific needs. We then use the toolbox to present a climatological analysis of spatially compounding heatwaves and cold spells in the global midlatitudes. Specific geographical areas, such as Western Russia, Central Europe, Southwestern Eurasia and Western North America, emerge as hotspots for concurrent temperature extremes. Concurrent heatwaves are becoming more frequent, longer-lasting and more extended in the Northern Hemisphere, while the opposite holds for concurrent cold spells. Concurrent heatwaves in the Southern Hemisphere are comparatively rare, but have been increasing in both number and extent. Notably, these trends in concurrent temperature extremes are significantly stronger than the corresponding trends in all temperature extremes.
Contrasting responses of vegetation productivity to intraseasonal rainfall in Earth System Models
Authors: Harris Bethan L. , Quaife Tristan , Taylor Christopher M. , Harris Phil P.
Published: January 2024

Abstract. Correctly representing the response of vegetation productivity to water availability in Earth System Models (ESMs) is essential for accurately modelling the terrestrial carbon cycle and the evolution of the climate system. We evaluate this response at the intraseasonal timescale in five CMIP6 ESMs by analysing changes in Gross Primary Productivity (GPP) after intraseasonal rainfall events and comparing to the responses found in a range of observation-based products. When composited around all intraseasonal rainfall events globally, both the amplitude and the timing of the GPP response show large inter-model differences, demonstrating discrepancies between models in their representation of water-carbon coupling processes. However, the responses calculated from the observational datasets also vary considerably, making it challenging to assess the realism of the modelled GPP responses. The models correctly capture that larger increases in GPP at the regional scale are associated with larger increases in surface soil moisture and larger decreases in atmospheric vapour pressure deficit. However, the sensitivity of the GPP response to these drivers varies between models. The GPP in NorESM is insufficiently sensitive to surface soil moisture perturbations when compared to any observational GPP product tested. Most models produce a faster GPP response where the surface soil moisture perturbation is larger, but the observational evidence for this relationship is weak. This work demonstrates the need for a better understanding of the uncertainties in the representation of water-vegetation relationships in ESMs, and highlights a requirement for future daily-resolution observations of GPP to provide a tighter constraint on global water-carbon coupling processes.
CoCO2-MOSAIC 1.0: a global mosaic of regional, gridded, fossil, and biofuel CO2 emission inventories
Authors: Urraca Ruben , Janssens-Maenhout Greet , Álamos Nicolás , Berna-Peña Lucas , Crippa Monica , Darras Sabine , Dellaert Stijn , Denier van der Gon Hugo , Dowell Mark , Gobron Nadine , Granier Claire , Grassi Giacomo , Guevara Marc , Guizzardi Diego , Gurney Kevin , Huneeus Nicolás , Keita Sekou , Kuenen Jeroen , Lopez-Noreña Ana , Puliafito Enrique , Roest Geoffrey , Rossi Simone , Soulie Antonin , Visschedijk Antoon
Published: January 2024

Abstract. Gridded bottom-up inventories of CO2 emissions are needed in global CO2 inversion schemes as priors to initialize transport models and as a complement to top-down estimates to identify the anthropogenic sources. Global inversions require gridded datasets almost in near-real time that are spatially and methodologically consistent at a global scale. This may result in a loss of more detailed information that can be assessed by using regional inventories because they are built with a greater level of detail including country-specific information and finer resolution data. With this aim, a global mosaic of regional, gridded CO2 emission inventories, hereafter referred to as CoCO2-MOSAIC 1.0, has been built in the framework of the CoCO2 project. CoCO2-MOSAIC 1.0 provides gridded (0.1∘ × 0.1∘) monthly emissions fluxes of CO2 fossil fuel (CO2ff, long cycle) and CO2 biofuel (CO2bf, short cycle) for the years 2015–2018 disaggregated in seven sectors. The regional inventories integrated are CAMS-REG-GHG 5.1 (Europe), DACCIWA 2.0 (Africa), GEAA-AEI 3.0 (Argentina), INEMA 1.0 (Chile), REAS 3.2.1 (East, Southeast, and South Asia), and VULCAN 3.0 (USA). EDGAR 6.0, CAMS-GLOB-SHIP 3.1 and CAMS-GLOB-TEMPO 3.1 are used for gap-filling. CoCO2-MOSAIC 1.0 can be recommended as a global baseline emission inventory for 2015 which is regionally accepted as a reference, and as such we use the mosaic to inter-compare the most widely used global emission inventories: CAMS-GLOB-ANT 5.3, EDGAR 6.0, ODIAC v2020b, and CEDS v2020_04_24. CoCO2-MOSAIC 1.0 has the highest CO2ff (36.7 Gt) and CO2bf (5.9 Gt) emissions globally, particularly in the USA and Africa. Regional emissions generally have a higher seasonality representing better the local monthly profiles and are generally distributed over a higher number of pixels, due to the more detailed information available. All super-emitting pixels from regional inventories contain a power station (CoCO2 database), whereas several super-emitters from global inventories are likely incorrectly geolocated, which is likely because regional inventories provide large energy emitters as point sources including regional information on power plant locations. CoCO2-MOSAIC 1.0 is freely available at zenodo (https://doi.org/10.5281/zenodo.7092358; Urraca et al., 2023) and at the JRC Data Catalogue (https://data.jrc.ec.europa.eu/dataset/6c8f9148-ce09-4dca-a4d5-422fb3682389, last access: 15 May 2023; Urraca Valle et al., 2023).
Radiocarbon analysis reveals underestimation of soil organic carbon persistence in new-generation soil models
Authors: Brunmayr Alexander S. , Hagedorn Frank , Moreno Duborgel Margaux , Minich Luisa I. , Graven Heather D.
Published: January 2024

Abstract. Reflecting recent advances in our understanding of soil organic carbon (SOC) turnover and persistence, a new generation of models increasingly makes the distinction between the more labile soil particulate organic matter (POM) and the more persistent mineral-associated organic matter (MAOM). Unlike the typically poorly defined conceptual pools of traditional SOC models, the POM and MAOM pools can be directly measured for their carbon content and isotopic composition, allowing for pool-specific data assimilation. However, the new-generation models' predictions of POM and MAOM dynamics have not yet been validated with pool-specific carbon and 14C observations. In this study, we evaluate 5 influential and actively developed new-generation models (CORPSE, Millennial, MEND, MIMICS, SOMic) with pool-specific and bulk soil 14C measurements of 77 mineral topsoil profiles in the International Soil Radiocarbon Database (ISRaD). We find that all 5 models consistently overestimate the 14C content (Δ14C) of POM by 67 ‰ on average, and 3 out of the 5 models also strongly overestimate the Δ14C of MAOM by 74 ‰ on average, indicating that the models generally overestimate the turnover rates of SOC and do not adequately represent the long-term stabilization of carbon in soils. These results call for more widespread usage of pool-specific carbon and 14C measurements for parameter calibration, and may even suggest that some new-generation models might need to restructure their simulated pools (e.g., by adding inert pools to POM and MAOM) in order to accurately reproduce SOC dynamics.