Climatic Implications Research Articles

Hot carbonates deep within the Chicxulub impact structure.

Constraining the thermodynamic conditions within an impact structure during and after hypervelocity impacts is extremely challenging due to the transient thermal regimes. This work uses carbonate clumped-isotope thermometry to reconstruct absolute temperatures of impact lithologies within and close to the ∼66 Myr old Chicxulub crater (Yucatán, México). We present stable oxygen (δ18O), carbon (δ13C), and clumped-isotope (Δ47) data for carbonate-bearing impact breccias, impact melt rock, and target lithologies from four drill cores on a transect through the Chicxulub structure from the northern peak ring to the southern proximal ejecta blanket. Clumped isotope-derived temperatures (T(Δ47)) are consistently higher than maximum Late Cretaceous sea surface temperatures (35.5°C), except in the case of Paleogene limestones and melt-poor impact breccias outside of the crater, confirming the influence of burial diagenesis and a widespread and long-lived hydrothermal system. The melt-poor breccia unit outside the crater is overlain by melt-rich impact breccia yielding a much higher T(Δ47) of 111 ± 10°C (1 standard error [SE]), which likely traces the thermal processing of carbonate material during ejection. Finally, T(Δ47) up to 327 ± 33°C (1 SE) is determined for the lower suevite and impact melt rock intervals within the crater. The highest temperatures are related to distinct petrological features associated with decarbonation and rapid back-reaction, in which highly reactive CaO recombines with impact-released CO2 to form secondary CaCO3 phases. These observations have important climatic implications for the Cretaceous-Paleogene mass extinction event, as current numerical models likely overestimate the release of CO2 from the Chicxulub impact event.

New Insights on the Formation of Nucleation Mode Particles in a Coastal City Based on a Machine Learning Approach.

Atmospheric particles have profound implications for the global climate and human health. Among them, ultrafine particles dominate in terms of the number concentration and exhibit enhanced toxic effects as a result of their large total surface area. Therefore, understanding the driving factors behind ultrafine particle behavior is crucial. Machine learning (ML) provides a promising approach for handling complex relationships. In this study, three ML models were constructed on the basis of field observations to simulate the particle number concentration of nucleation mode (PNCN). All three models exhibited robust PNCN reproduction (R2 > 0.80), with the random forest (RF) model excelling on the test data (R2 = 0.89). Multiple methods of feature importance analysis revealed that ultraviolet (UV), H2SO4, low-volatility oxygenated organic molecules (LOOMs), temperature, and O3 were the primary factors influencing PNCN. Bivariate partial dependency plots (PDPs) indicated that during nighttime and overcast conditions, the presence of H2SO4 and LOOMs may play a crucial role in influencing PNCN. Additionally, integrating additional detailed information related to emissions or meteorology would further enhance the model performance. This pilot study shows that ML can be a novel approach for simulating atmospheric pollutants and contributes to a better understanding of the formation and growth mechanisms of nucleation mode particles.

Drivers controlling black carbon temporal variability in the lower troposphere of the European Arctic

Abstract. Black carbon (BC) is a short-lived climate forcer affecting the Arctic climate through multiple mechanisms, which vary substantially from winter to summer. Several models still fail in reproducing BC seasonal variability, limiting the ability to fully describe BC climate implications. This study aims at gaining insights into the mechanisms controlling BC transport from lower latitudes to the Arctic lower troposphere. Here we investigate the drivers controlling black carbon daily and seasonal variability in the Arctic using generalized additive models (GAMs). We analysed equivalent black carbon (eBC) concentrations measured at the Gruvebadet Atmospheric Laboratory (GAL – Svalbard archipelago) from March 2018 to December 2021. The eBC showed a marked seasonality with higher values in winter and early spring. The eBC concentration averaged 22 ± 20 ng m−3 in the cold season (November–April) and 11 ± 11 ng m−3 in the warm season (May–October). The seasonal and interannual variability was mainly modulated by the efficiency of wet scavenging removal during transport towards higher latitudes. Conversely, the short-term variability was controlled by boundary layer dynamics as well as local-scale and synoptic-scale circulation patterns. During both the cold and warm seasons, the transport of air masses from Europe and northern Russia was an effective pathway for the transport of pollution to the European Arctic. Finally, in the warm season we observed a link between the intrusion of warm air from lower latitudes and the increase in eBC concentration. Changes in the synoptic-scale circulation system and precipitation rate in the Northern Hemisphere, linked to climate change, are expected to modify the BC burden in the Arctic.

Unravelling the atmospheric and climate implications of hydrogen leakage

In recent years, hydrogen is adopted as a clean source of energy to combat emissions and climate change resulting from fossil fuels. All along the value chain of hydrogen economy, leakage of hydrogen is possible which is expected to have profound impacts on air quality and climate. In the present study, quantum chemistry calculations are employed to understand the atmospheric oxidation mechanism of H2 by OH and O3. The results reveal that oxidation of H2 by both the OH and O3 are both possible and the reaction of H2 with O3 is thermodynamically favoured over its reaction with OH radical. The O3 initiated reaction of H2 is around 80 kcal/mol more exothermic than that of the OH initiated reaction. The O3 initiated reactions of H2 has longer lifetime in the atmosphere when compared to OH initiated reactions. This shows that in addition to undergoing OH radical initiated reaction, where ozone is formed as a product, the H2 can also undergo oxidation by O3 leading to the tropospheric ozone loss processes. Depending upon the background atmospheric concentration, either the OH radical generation is suppressed and methane is formed or the H2 can undergo oxidation with O3. The global warming potential (GWP) weighted emissions for hydrogen leakage incidents reported in the literature is obtained. The emissions are maximum from the hydrogen leakage in transportation and power sectors and minimum in the pipeline leakage. Taken together the atmospheric oxidation potential of H2 by OH radical and O3 oxidation and its GWP weighted emissions, it is clear from the study that the atmospheric and climate implications of H2 leakage is relatively less. The present study is based on molecular level and a rigorous model accounting the atmospheric composition is required for better understanding of the atmospheric and climate implications.

Variability of biological traits of Bulinus truncatus and Biomphalaria pfeifferi, the intermediate host snails of schistosomiasis, from three climatic zones of Côte d’Ivoire

Background: Schistosomiasis is endemic throughout all regions of Côte d’Ivoire, however, species of the intermediate snail host vary across bioclimatic zones. Hence, a deeper knowledge of the influence of climatic on the life history traits of the intermediate snail host is crucial to understand the environmental determinants of schistosomiasis in a rapidly changing climate. The aim of this study was to run a common garden experiment to assess differences in survival, somatic growth and fecundity of both Bulinus truncatus and Biomphalaria pfeifferi snails collected in three different bioclimatic areas.Methods: A cross-sectional malacological survey was conducted in February 2021 in the south, center and north of Côte d’Ivoire. We sampled two populations of B. truncatus, the intermediate host snail of Schistosoma haematobium, from northern and central Côte d’Ivoire, and two populations of Bi. pfeifferi, the intermediate host snail for Schistosoma mansoni, from the southern and central regions. Snails collected at the human-water contact sites were brought in the laboratory where they reproduced. The first generation snails (G1) for each population were reared under the same laboratory conditions, i.e., at 24°C–26°C, during 63 days (9 weeks), to estimate survival, growth, and fecundity.Results: We found that G1Bulinus snails from the north population showed higher survival and growth rates during our study and higher number of eggs at first reproduction, compared to the ones from the central region. For Bi. pfeifferi, no significant difference in survival rate was observed between G1 snails from the southern and central populations, whereas those from the south exhibited higher growth rates and higher number of eggs per individual at first reproduction than G1 snails from the central population.Conclusion: Our study provides evidence for heterogeneity in snails’ life-history traits in response to temperature among the populations from the three climatic regions. Further experiments from multiple populations are needed to confirm that snails express traits under optimal conditions, can lead to expansion of their geographical range and hence an increase in the risk of schistosomiasis transmission. Transplantation experiments will be required to assess implications of the changing climate on snails persistence, distribution and abundance.

Assessment of Arctic sea ice and surface climate conditions in nine CMIP6 climate models

ABSTRACT The observed retreat and anticipated further decline in Arctic sea ice holds strong climate, environmental, and societal implications. In predicting climate evolution, ensembles of coupled climate models have demonstrated appreciable accuracy in simulating sea-ice area trends throughout the historical period, yet individual climate models still show significant differences in accurately representing the sea-ice thickness distribution. To better understand individual model performance in sea-ice simulation, nine climate models were evaluated in comparison with Arctic satellite and reanalysis-derived sea-ice thickness data, sea-ice area records, and atmospheric reanalysis data of surface wind and air temperature. This assessment found that the simulated spatial distribution of historical sea-ice thickness varies greatly between models and that several key limitations persist among models. Primarily, most models do not capture the thickest regimes of multiyear ice present in the Wandel and Lincoln seas; those that do often possess erroneous positive bias in other regions such as the Laptev Sea or along the Eurasian Arctic Shelf. This analysis provides enhanced understanding of individual model historical simulation performance, which is critical in informing the selection of coupled climate model projections for dependent future modeling efforts.

Counselling implications of school climate and learning outcomes of students in senior secondary schools in Delta State, Southern Nigeria

School climate from studies over the last two decades has been shown to affect students and the process of learning. The purpose of this study, therefore, was to explore the school climate of some selected schools and also to determine the relationship between students' and teachers' perceptions of school climate and students' performance in mini WAEC tests. It is a cross-sectional survey of 664 randomly selected SSS 3 (three) students and 90 teachers in nine secondary schools in the 3 Senatorial districts in Delta State. Two sets of instruments were used to collect data for this study: School Climate Questionnaires (SCQs) and past WAEC objective questions in three subjects (English Language, Mathematics and Biology). The data collected were analyzed using descriptive and inferential statistics. The findings revealed that most students perceived their school's social and academic environment as being poor. A significant difference was found in the physical environment of the school and the performance of the students in Biology. It is recommended that workshops and seminars be organized for school heads and teachers to enhance the positive school climate.

The Role of Principal Competence, Teacher Competency in School Accreditation Through Primary School Education Quality Standards, and Its Implications for Organizational Climate

<p>Kompetensi kepala sekolah dan kompetensi guru merupakan hal penting untuk meningkatkan standar mutu dan iklim organisasi. Tujuan penelitian ini adalah untuk mengembangkan standar mutu Pendidikan, kompetensi kepala sekolah dan guru terhadap iklim organisasi dan akreditasi sekolah dasar di kota Cilegon. Jenis penelitian ini adalah kuantitatif dengan metode pengumpulan data melalui survey pada guru sekolah dasar berjumlah 200 orang dengan alat analisis Structural equation Modelling (SEM). Hasil penelitian antara lain: 1) ada pengaruh Kompetensi Kepala sekolah terhadap akreditasi sekolah dasar. 2) ada pengaruh Kompetensi Kepala sekolah terhadap iklim organisasi. 3) Standar ada pengaruh Kompetensi Kepala Sekolah Terhadap Standar Mutu. 4) ada pengaruh Pengaruh standar mutu terhadap akreditasi sekolah dasar. 5) ada Pengaruh Kompetensi guru terhadap akreditasi sekolah dasar. 6) ada Pengaruh Kompetensi guru terhadap iklim organisasi. 7) ada Pengaruh Pengaruh Kompetensi guru terhadap standar mutu. 8) Mediasi. Variabel kompetensi kepala sekolah dan guru terhadap standar mutu dengan mediasi akreditasi sekolah dasar, dan kom P value 0.000 < 0.05 yang artinya terjadinya mediasi semu (<em>partially</em><em> mediating</em>).</p>

Feature-oriented reconstruction of vertical temperature profile: A feasibility study in the Northwest Pacific Ocean

The Northwest Pacific is an area rich in oceanic frontal system that influences regional circulation patterns, heat transport, and biogeochemical processes. Understanding the three-dimensional thermal structure of the western subarctic front is essential for studying its dynamics and climate implications. In this study, we developed an empirical feature model to reconstruct the thermal structure of ocean fronts using satellite observations and ARMOR3D product which assimilates Argo data. The model established an empirical relationship between temperature profiles and the front centerline, as well as the temperature difference across the centerline. The reconstructed temperature profiles agree well relative to the validation dataset with a mean bias smaller than 0.5◦C from the sea surface down to 1000 m, demonstrating the model's reliability. This research offers a methodology for reconstructing the three-dimensional thermal structure of oceanic fronts, providing insights into further studies related to the intrinsic features of ocean fronts.

Impact of electricity generation, consumption, energy trade, and ICT on the environment in Pakistan: a NARDL and ARDL analysis

ABSTRACT Global concern over socioeconomic activities’ environmental impact is undeniable, given their implications for climate and human welfare. In our study, we analyze Pakistan’s landscape, with emphasis on the effects of electricity generation and consumption (both symmetric and asymmetric), energy trade, and the role of information and communication technology (ICT). We harnessed data from 1993 to 2020, sourced from World Development Indicators, Climate Watch, and the USA EIA. Our analysis involved application of the Nonlinear Autoregressive Distributed Lag model and the Autoregressive Distributed Lag bounds testing methods. Our results reveal that electricity consumption, whether experiencing positive or negative shocks, exhibits a tendency to elevate emissions over the long term. Similarly, shocks in electricity generation from fossil fuels, whether positive or negative, have adverse environmental consequences both in the short and long run. A negative shock in electricity generation from renewable and alternative sources triggers environmental degradation. Remarkably, nuclear energy plays a pivotal role in bolstering environmental sustainability in Pakistan. Conversely, we identified factors contributing to ecological degradation, including imports of coal, crude oil, metallurgical coke, and ICT usage, in the long run. Equally, trade and natural resources rent emerge as mitigating factors over time. Ultimately, ourstudy underscores the importance of diversifying the energy mix, with a particular emphasis on expanding the renewable sources for reducing emissions and fostering environmental sustainability in Pakistan. Additionally, our research suggests that leveraging natural resources rent and trade capabilities can pave the way for an eco-friendlier future in the country.

Pyrolysis of Municipal Plastic Waste to Produce Alternate Fuel

This research concentrates on the pyrolysis of municipal plastic waste (MPW) to produce an alternate fuel and its thermal comparison with petrol and diesel. It is a viable response to the growing problem of plastic waste disposal. Fuels made from petroleum and plastics contain carbon and hydrogen and are classified as hydrocarbons. Plastics are made up of fossil fuel-based chemicals such as natural gas or crude oil. It is non-biodegradable waste, mainly consisting of approx 15% of total Municipal Solid Waste (MSW). Plastics are pivotal in today's world and are excessively used in households, industry and other fields due to their lightweight, durability, flexibility and inexpensive ability to produce. The need for plastics is expanding every day, posing a significant danger to the climate.The pyrolysis process is a waste-to-energy technological option for producing alternative fuels to replace fossil fuels. It is a thermochemical decomposition of organic material at high temperatures without oxygen or an inert gas atmosphere. Municipal Plastic Waste is depolymerized, pyrolyzed, catalytically cracked, and fractionally distilled to produce various value-added petroleum-derived fuels via pyrolysis which can be used to replace low diesel oils. The pyrolysis method has the benefit of being able to handle unsorted polymers. The material's pretreatment is simple. Plastics must be sorted, dried, and shredded. Pyrolysis, instead of incineration, doesn't emit harmful or hazardous gases. Transforming municipal plastic waste into energy has significant environmental, climatic, and economic implications.

Farmers perspectives on options for and barriers to implementing climate resilient agriculture and implications for climate adaptation policy

The impacts of climate change in low lying coastal areas, such as Bangladesh, are adversely affecting food and livelihood security, requiring adaptation to build resilience. However, effective implementation is limited by a lack of local-level knowledge regarding the barriers that prevent adoption and up-scaling of climate resilient agriculture (CRA). Case studies in coastal Bangladesh provide novel insights regarding barriers to planned and autonomous adaptation from the perspective of farmers facing multiple climate change impacts across seven key dimensions of CRA (agrometeorology services, water management practices, nutrient management activities, technologies and knowledge management activities, infrastructure development, socio-economic resilience, and institutions and good governance). Farmers generally perceive that adaptation actions increase resilience in crop production systems and their surrounding social systems, but also identify the important barriers that inhibit or constrain planned and autonomous adaptation opportunities. Planned adaptation actions are perceived to be limited by institutional arrangements and lack of implementation capacity. Autonomous adaptation was found to be dependent on income level, farm-holding size, access to input resources and services and peer/social influences. Planned and autonomous adaptation actions were both affected by specific social and geographic contexts and cultural factors. Recommendations are suggested to address key constraints and thereby promote CRA in coastal agricultural landscapes in Bangladesh and in other developing countries confronting similar challenges.

Socio-demographic Context of Resilience for Adaptation to Climate Change and Implication for Agricultural Extension in Buffelspruit, South Africa

The study examined the socio-demographic characteristics of smallholder farmers’ and resilience strategies for adaptation to climate change in Buffelspruit, South Africa. The objectives of the study were to determine local resilience strategies used by farmers and examine adoption behaviour in the use of local resilience strategies for mitigating climate change. The study was conducted in Buffelspruit community. A total number of 306 participants were selected randomly for this study. Structured and semi-structured questionnaires were used for data collection. The adoption behaviour of the farmers in the use of local resilience strategies was analysed using the logit model. Crop rotation, crop diversification and the adjustment of planting dates were the resilience strategies used by farmers. The result from the logit analysis reveals that gender (p = 0.047), level of education (p = 0.16), employment (p = 0.043), farm skills (p = 0.058), extension services (p = 0.011) and farm size (p = 0.022) influenced the adoption of climate resilient strategies in the study area. Extension education must move beyond technical training to enhance farmers’ abilities for planning, problem solving, critical thinking and leadership skills to work with multiple stakeholders. Extension must be proactive with capacity development in climate change education.

Evaluation of meteorological characteristics and the influence of the Southern Annular Mode at newly established Bharati Station, East Antarctica

The Indian Antarctic program, a multi-disciplinary and multi-institutional program initiated in 1981 with the first expedition to Antarctica, has been instrumental in advancing our understanding of Antarctic meteorology and its global climate implications. This study focuses on the latest meteorological characteristics of newly established research base Bharati aiming to unravel the climate dynamics of Bharati station in East Antarctica. The meteorological data for the period December 2014 to December 2022 have been analysed in present study. We observed the highest maximum temperature of 9.9 °C on January 5, 2018, and the lowest minimum temperature of −40.3 °C on September 6, 2016. The monthly mean temperature exhibits pronounced seasonal variation, with a summer maximum of approximately 0 °C in December and January, and a winter minimum of about −19 °C from May to September. While the eight-year observations are not sufficient for studying long-term trends, we identify a slight increasing tendency in temperature at Bharati. In addition to temperature, we examined the characteristics of pressure, relative humidity, precipitation, wind, and blizzards. The analysis reveals a negative correlation between the Southern Annular Mode (SAM) and temperature and pressure at Bharati. Station experiences predominantly easterly and northeasterly winds. The upper air data were obtained using radiosonde and ozonesonde ascents, enhancing our understanding of the atmospheric conditions in the region. These results provide important knowledge about the weather in Bharati and how it relates to the Southern Annular Mode. Understanding this helps us comprehend how East Antarctica weather influences global climate patterns.

Acoustic levitation of pollen and visualisation of hygroscopic behaviour

Abstract. Pollen are hygroscopic; therefore, they have the potential to act as cloud condensation nuclei (CCN) in the atmosphere. This could have uncertain implications for cloud processes and climate as well as plant biodiversity and human health. Previous studies have investigated the hygroscopic swelling of pollen, linked to CCN activity by the κ-Köhler theory, using methods that follow observed mass increase by electrodynamic balance (EDB) or vapour sorption analyser. This study uses an acoustic levitator to levitate pollen grains in the true aerosol phase and uses a macroscope to image the pollen to investigate hygroscopic behaviour when relative humidity (RH) is changed. Two pollen species were studied in this work: Lilium orientalis (oriental lily) and Populus deltoides (eastern cottonwood). Both species were successfully levitated; however, the smaller Populus deltoides showed greater instability throughout experiments. The quality of images taken by the macroscope, and thus calculations of pollen area and aspect ratio, varied significantly and were sensitive to lighting conditions as well as to levitated pollen grain movement and orientation. Experiments with surface-fixed pollen grains were also conducted. They showed evidence that pollen hygroscopic swelling could be observed by the macroscope. The produced results were comparable with previously reported mass increase values. Although less accurate than methods that measure mass changes, the acoustic levitator and macroscope set-up offer an attractive alternative by virtue of being commercial, off-the-shelf, low-cost, and versatile techniques. A key advantage of this method is that it is possible to visually observe particle shape dynamics under varying environmental conditions.

Workshop report: PlioWest – drilling Pliocene lakes in western North America

Abstract. The Pliocene Epoch is a focus of scientific interest as a period of sustained global warmth, with reconstructed CO2 concentrations and a continent configuration similar to modern. Numerous studies suggest that the Pliocene was warmer and largely wetter than today, at least in the subtropics, which contrasts with the long-term hydroclimatic response of drying conditions predicted by most climate model simulations. Two key features of Pliocene warmth established from sea surface temperature reconstructions could affect dynamic changes that influence the hydrologic cycle: (1) a weaker Pliocene zonal gradient in sea surface temperature (SST) between the western and eastern equatorial Pacific resembling El Niño-like conditions and (2) polar-amplified Pliocene warmth, supporting a weaker Equator-to-pole temperature gradient. The distribution of wet conditions in western North America and the timing of late Pliocene–Quaternary aridification offer the potential to evaluate the relative roles of these two external forcings of the climate in western North America, with broader global implications for Mediterranean-type climate (MTC) regions. We convened a virtual ICDP workshop that spanned a 2-week period in September 2021, to choose optimal drill sites and legacy cores to address the overall scientific goals, flesh out research questions, and discuss how best to answer them. A total of 56 participants from 12 countries (17 time zones), representing a wide range of disciplines, came together virtually for a series of plenary and working group sessions. We have chosen to study five basins (Butte Valley, Tule Lake, Lake Idaho, Searles Lake, and Verde Valley) that span 7 ∘ of latitude to test our hypotheses and to reconstruct the evolution of western North American hydroclimate with special focus on the time ranges of 4.5–3.5 and 3–2.5 Myr. Although individual Pliocene lake records occur in many areas of the world, the western North American basins are unique and globally significant as deep perennial freshwater Pliocene lakes latitudinally arrayed in a MTC region and are able to capture a response to Pacific forcing. We propose new drill cores from three of these basins. During the workshop, we discussed the stratigraphy and subsurface structure of each basin and revised the chronological frameworks and the basin-to-basin correlations. We also identified the best-suited proxies for hydroclimate reconstructions for each particular basin and put forward a multi-technique strategy for depth–age modeling. Reconstructions based on data from these sites will complement the SST reconstructions from global sites spanning the last 4.5 Ma and elucidate the large-scale hydrological cycle controls associated with both global warming and cooling.

Spatial and temporal distributions of clay minerals in the central Andaman Sea: Provenances and sedimentary processes over the last 42 kyr

The uplift of the Tibetan Plateau has led to the formation of the world’s largest sediment “source–sink” system in the northeastern Indian Ocean, and seafloor sediments record rich environmental and climatic information during the accumulation process, making it an ideal area to reconstruct past sedimentary processes. To reveal fine sediment provenance and climatic implications, we present a sedimentary reconstruction during the past 42 kyr based on clay mineral analyses of sediments from core ADM-159 retrieved from the central Andaman Sea. The clay minerals mainly consist of illite (I, 27%–47%) and kaolinite (K, 8%–37%) with minor smectite (S, 11%–37%) and chlorite (C, 11%–37%). Provenance analyses show that the illite-dominated clay minerals are mainly derived from terrestrial sources of detrital material input from the Irrawaddy River, indicating a primary supply of fine sediment from Myanmar terrestrial material. Considering the stable sediment provenance, S/K, S/(I+C), and the illite chemical index were chosen to reconstruct the transport pattern of the fine fraction sediment over the last 42 kyr. S/K and S/(I+C) showed relatively consistent trends over time with relatively high values at 32–25 and 15–6 ka BP, indicating a strong supply and transport capacity of fine particulate matter. In contrast, relatively low values of S/K and S/(I+C) occurred at 25–15 ka BP, indicating a relatively weak deposition process of fine sediments in the study area. The trends in S/K and S/(I+C) are roughly consistent with the variations in solar radiation. Together with the illite chemical index, these trends indicate that solar activity controlled the weathering and sedimentation of fine-grained sediments. We also found significant periodicities in our clay mineral records at 25.05 and 0.473–0.477 kyr, suggesting that the parameters of the Earth’s orbit and solar radiation were potential driving mechanisms of the changes in regional climate. Moreover, monsoon precipitation triggered by the movement of the intertropical convergence zone was another important factor controlling the supply and transport of fine particulate matter in the study area, especially the weak precipitation during the last deglacial period and the relatively strong precipitation during the Holocene, so we could draw a conclusion that precipitation during these periods had significant effects on the weathering, erosion, and transport of fine particulate terrestrial materials over the last 42 kyr.

Vegetation Trend Detection Using Time Series Satellite Data as Ecosystem Condition Indicators for Analysis in the Northwestern Highlands of Ethiopia

Vegetation is an essential component of the terrestrial ecosystem and has changed significantly over the last two decades in the Northwestern Highlands of Ethiopia. However, previous studies have focused on the detection of bitemporal change and lacked the incorporation of entire vegetation time series changes, which are considered significant indicators of ecosystem conditions. The Normalized Difference Vegetation Index (NDVI) time series dataset from the Moderate-Resolution Imaging Spectroradiometer (MODIS) is an efficient method for analyzing the dynamics of vegetation change over a lengthy period using remote sensing techniques. This study aimed to utilize time series satellite data to detect vegetation changes from 2000 to 2020 and investigate their links with ecosystem conditions. The time-series satellite processing package (TIMESAT) was used to estimate the seasonal parameter values of NDVI and their correlation across the seasons during the study period. Break Detection for Additive Season and Trend (BFAST) was applied to identify the year of breakpoints, the direction of magnitude, and the number of breakpoints. The results were reported, analyzed, and linked to ecosystem conditions. The overall trend in the study area increased from 0.58 (2000–2004) to 0.65 (2015–2020). As a result, ecosystem condition indicators such as peak value (PV), base value (BV), amplitude (Amp), and large integral (LI) exhibited significant positive trends, particularly for Acacia decurrens plantations, Eucalyptus plantations, and grasslands, but phenology indicator parameters such as start of season (SOS), end of season (EOS), and length of season (LOS) did not show significant trends for almost any vegetation type. The most abrupt changes were recorded in 2015 (24.7%), 2012 (18.6%), and 2014 (9.8%). Approximately 30% of the vegetation changes were positive in magnitude. The results of this study imply that there was an improvement in the ecosystem’s condition following the establishment of the Acacia decurrens plantation. The findings are considered relevant inputs for policymakers and serve as an initial stage for the assessment of the other environmental and climatic implications of Acacia decurrens plantations at the local scale.

Global database of cement production assets and upstream suppliers

Cement producers and their investors are navigating evolving risks and opportunities as the sector’s climate and sustainability implications become more prominent. While many companies now disclose greenhouse gas emissions, the majority from carbon-intensive industries appear to delegate emissions to less efficient suppliers. Recognizing this, we underscore the necessity for a globally consolidated asset-level dataset, which acknowledges production inputs provenance. Our approach not only consolidates data from established sources like development banks and governments but innovatively integrates the age of plants and the sourcing patterns of raw materials as two foundational variables of the asset-level data. These variables are instrumental in modeling cement production utilization rates, which in turn, critically influence a company’s greenhouse emissions. Our method successfully combines geospatial computer vision and Large Language Modelling techniques to ensure a comprehensive and holistic understanding of global cement production dynamics.

Anaerobic Isoprene-Degrading Microorganisms and their Impact on Microbial Methane Dynamics in Deep-Sea Carbonates and Eucalyptus-Leaf Sediments

Isoprene, a highly abundant biogenic volatile organic compound, has emerged as a crucial yet overlooked factor in addressing climate change. Despite its widespread production in all forms of life, comprehensive data on its global biogeochemical cycle remain scarce. Isoprene's reactivity in the atmosphere influences methane concentrations, with detrimental implications for climate, air quality, and health. Conversely, methane is abundant in marine and terrestrial subsurface environments, where deep-sea carbonates serve as hotspots for microorganisms performing anaerobic methane oxidation—an essential process in long-term methane storage and removal from the marine carbon cycle. Recent studies by Beckmann et al. (2020), Prouty et al. (2020) have shed light on novel metabolic pathways utilized by microbial communities in carbonates for methane oxidation. Similarly, in terrestrial environments, eucalyptus trees, as the highest emitters of isoprene, may harbor microorganisms capable of metabolizing isoprene alongside methane-oxidation and formation in eukalyptus leaf detritus. However, little is known about the fate of isoprene and the potential microbial communities involved in its metabolism within deep-sea carbonates and eucalyptus-leaf sediments, potentially impacting methane metabolism. Our study aims to unravel the anaerobic pathways of microbial isoprene degradation and investigate the effects of isoprene abundance and degradation on microbial methane production and oxidation. We detected anaerobic isoprene-degradation in deep-sea carbonates and terrestrial eukalyptus-leave sediments, where methane oxidation and methane formation was pronounced. Surprisingly, the presence of isoprene inhibited mcirobial methane-oxidation as well as methane-formation, suggesting an substantial impact of the presence of isoprene on methane cycling and storage. We are currently characterizing and isolating the microorganisms involved in the isoprene and methane metabolism in these enrichment cultures.