Beginning in 1964, an academic lineage of Robert DuBois and his students, Daniel Wolfman and Jeffrey Eighmy, developed dedicated United States-based archaeomagnetic research programs. Collectively, they analyzed over 5377 archaeomagnetic sites, primarily from North America, dated to less than 2000 years old. Yet despite their decades of effort, few journal publications resulted. Most of their published results are embedded in archaeological reports, often without technical data, which limits the data’s accessibility. Furthermore, when published, the results are generally averaged at the site-level using statistical conventions different from today’s standards, limiting the data’s comparability and (re)usability. In 2015, we undertook a salvage archival study to digitize the surviving data and metadata from the scientists’ individual estates and emeritus collections. We digitized measurement data from more than 51,000 specimens, reinterpreted them using modern conventions, and uploaded them to the FAIR-adhering magnetic data repository - MagIC. The reinterpreted site-level results from the three laboratories are mutually consistent, permitting the individual datasets to be combined and analyzed as single regional entities. Through incorporation into the MagIC repository, these legacy data are now accessible for incorporation into archaeomagnetic and global magnetic field modeling efforts, critical to understanding Earth’s magnetic field variation through time. In the Four Corners region of the United States Southwest, this digitized archive advances the development of a new regional paleosecular variation curve used in archaeomagnetic dating. This project highlights both the value and complexities of managing legacy data; the many lessons learned set a precedent for future paleomagnetic data recovery efforts.

3D-printing techniques allow us to visualise geophysical concepts that are difficult to grasp, making them perfect for incorporation into teaching and outreach packages. Abstract models, often represented as 2D coloured maps, become more tactile when represented as 3D physical objects. In addition, new questions tend to be asked and different features noticed when handling such objects, while they also make outreach and education more inclusive to the visually impaired. Some of our most effective models are simply exaggerated planetary topography in 3D, including Earth, Mars and the Moon. The resulting globes provide a powerful way to explain the importance of plate tectonics in shaping a planet and linking surface features to deeper dynamic processes. In addition, we have developed a simple method for portraying abstract global models by 3D printing modified globes of surface topography, representing the parameter of interest as additional, exaggerated long-wavelength topography. This workflow has been applied to models of dynamic topography, the geoid and seismic tomography. In analogy to Russian nesting dolls, the resulting “seismic matryoshkas” have multiple layers that can be removed by the audience to explore the structures present deep within our planet and learn about the ongoing dynamic processes. While these 3D objects are easily printed on a cheap (<300 GBP, 400USD) desktop 3D-printer, the printing times still prohibit large-scale production. To ensure that there is sufficient material in a teaching setting, we have therefore also developed complementary paper equivalents. By projecting the coloured maps onto a dodecahedron, we developed cut-out-and-fold models to be handed out in a classroom setting to complement the 3D printed globes used for demonstration purposes. Together with animations, suggested questions and instructor “cheat-sheets”, these materials form a complete teaching and outreach package that is both interactive and inclusive.

Open data, data that anyone can access, use, and share have found its place in the current research landscape. Yet, there are many waters to navigate for open access data. Repositories such as BCO-DMO are here to make that journey easier; juggling data principles and policies, funding requirements, publication specifications, research specifics, archiving and discovery through online search engines. BCO-DMO is a domain-specific repository serving highly heterogeneous biological and chemical oceanographic data. The scale of our data ranges from atmospheric aerosols to the bottom of the seafloor, microbes to megafauna. We assist investigators supported through NSF and private funders throughout the Data Life Cycle. We not only have in-house data managers that extensively curate the data and assist submitters in complying with the F.A.I.R Data Principles, but we also develop resources and architecture to tackle technology hurdles associated with these principles to ease data sharing on the behalf of researchers: Designing and implementing ontologies to increase discovery of the data Developing systems to track provenance Creating and improving standard operating procedures to ensure consistent data processing Providing APIs for improved interoperability Developing an automated submission system to ease data sharing burden To make sure that everything we develop addresses community needs, we continue to seek feedback on our processes (i.e what hurdles does the community have with their data and how can we help to overcome them) through a strategic planning committee and continued communication with submitters. We take part in several broader data community initiatives to improve data interoperability and reuse and demonstrate trustworthiness by obtaining CoreTrustSeal certification. How do you determine an appropriate repository to openly share your data? Is BCO-DMO on your list of choices? Let’s hear about it.

This study conducts an analysis of the polar numerical noise in the barotropic shallow-water version of the Grid-point Atmospheric Model of IAP LASG (GAMIL-SW) and provides a good solution to the problem. GAMIL-SW suffers from numerical noise in the polar region in some ideal test cases, which is likely to be detrimental to the full physical model. The noise is suspected to be related to the nonlinear advection term in the momentum equation. Thus, a new shallow-water model with a vector-invariant form of the momentum equation is developed on the latitude-longitude grid to analyze the polar noise. It is found that the version with meridional wind component staggered on the pole is free from noise, while the version with zonal wind component staggered on the pole is still contaminated. By redefining the polar relative vorticity, the polar noise is eliminated in the latter version. In addition, the test cases demonstrate that the new shallow-water model maintains the properties of the original GAMIL-SW with respect to numerical accuracy and computational stability. This study helps to identify appropriate governing equations to further develop the next generation of GAMIL dynamical core.

The global distribution and variations of the monthly mesopause temperature are presented during 2002-2019 covering the latitudes of 83°S-83°N based on Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) observations. To investigate the long-term trend and solar response of the mesopause temperature, a three-component harmonic fit is first applied to remove the seasonal variation from the monthly temperature data series. Then a multiple linear regression model is performed to residual temperatures versus constant, time series, solar activity, and geomagnetic activity terms. In this study, the mesopause temperature shows a cooling trend through all latitudes ranging from -0.002 to -0.113 K/year with a mean of -0.069 ± 0.036 K/year. The cooling trends in the southern hemisphere are observed to be relatively stronger than those in the northern hemisphere. For high latitudes (60°– 80°), significant negative trends can be detected during the non-summer time, while no significant trends are found for summertime. The mesopause temperature shows apparent positive responses to solar activity through all latitudes ranging from 2.74 to 4.76 K/100sfu with a mean of 3.94 ± 0.59 K/100sfu, which are more significant and stable in the northern hemisphere. There is a pronounced drop in solar response near the equator, which could be caused by tidal forcing at low latitudes. It is noteworthy that the length of the time interval for analysis is the main factor influencing the quality of the results. Our results, using an eighteen years interval, are expected to be a robust reference for the mesopause temperature variations.

Climate models contain atmospheric and oceanic components that are coupled together to simulate the thermodynamic and dynamic processes during air-sea interactions. Community Earth System Model (CESM, version 1.2.1) is a state-of-the-art coupled model that is widely used and participates in Coupled Model Intercomparison Projects. Community Atmospheric Model (CAM), the atmospheric component of CESM, is based on the finite-volume dynamic core, which utilizes staggered Arakawa-D grids. However, the dynamics-physics (D-P) coupling in CAM causes the prognostic winds of the dynamic core be interpolated onto non-staggered locations, which affects the wind structure for computing the air-sea interaction and dynamical coupling. In this study we propose a new scheme that eliminates the extra interpolation during D-P coupling for the atmosphere-ocean interaction. By numerical experiments and comparative study of the new scheme, we show that it improves the simulated climatology in key regions including eastern-boundary upwelling regions and Southern Oceans. In turn, existing problems of the model, such as warm SST biases, are reduced. The new scheme contain code changes in CAM and the coupler, and they are provided as open-source files. Similar approaches can also be adopted in coupled models that utilize the atmospheric components with on staggered dynamics and physics, such as spectral-element method based CAM.

The Engineering & Physical Sciences Division of the UC Berkeley Library partners with researchers to support the entire research life cycle. Since 2016, the division’s Science Data Librarian has offered Research Data Management training that covers data management, storage, documentation, and sharing. Based on this established work, division librarians piloted a series of open science workshops in 2019. The Earth & Planetary Sciences (EPS) Department was chosen as the target department for this work. Librarians began by replacing their traditional orientation session, focused on library procedures and resources, with an approach that highlighted local support for open research workflows. Scheduled throughout the fall semester of 2019, the sessions focus on trending methods and workflow tools relevant to students as they launch their research including: Introduction to Research Workflows and Literature Searching Dynamic data management, publishing and citation Citation Management Collaborative writing in LaTeX with Overleaf Jupyter Notebooks best practices Approaches to Github and reproducible code Publishing and authorship trends in the Earth Sciences The workshops draw together expertise from the EPS department and around campus, offering students a scaffolded introduction to local resources. Unlike a bootcamp or one-time workshop model, students learn material over the course of several months giving them the opportunity to attempt, adapt and develop new methods. The workshops also fill a need expressed by earlier graduate cohorts–domain specific sessions that take place within their building–making this an effective approach for reaching students and introducing foundational research methods. Trainers benefit by encountering a cohesive audience and creating content that will can be applied to other disciplines. Pilots such as this build communities of practice, test methodologies and provide an opportunity to scale trainings to a broader audience.

Heat transport plays a crucial role in igneous processes, and the thermal evolution of the interiors of terrestrial bodies. Thermal conductivity is a product of density (ρ), thermal diffusivity (D) and heat capacity (CP). We measured Dand CPas a function of temperature for a suite of planetary analog lavas relevant to the Moon, Mars, Mercury, Io and Vesta. Heat capacity measurements were conducted by differential scanning calorimetry (DSC) on glasses and liquids covering temperatures from 400 to 1750 K, Dmeasurements were conducted by laser-flash analyses (LFA) on glasses from room temperature up to their melting point slightly above the glass transition (Tg), and densities were already known. Our results demonstrate that the variability of Dand CPis very composition-specific, making thermal conductivity (k= DρCP) strongly composition-dependent. We present an empirical model to estimate Dof glasses as a function of temperature and composition, with 2σ uncertainty of 0.040 mm2s-1. Thermal diffusivity of the corresponding melt can be calculated with an uncertainty of 0.044 mm2s-1, but only independent of temperature. The model for Dpresented here, in combination with already available models to calculateCPand ρ, allows to predict thermal conductivity for a wide range of compositions for glasses and melts relevant to major planetary objects in the solar system. We show that basaltic liquids have thermal conductivities between 1.0 and 1.7 Wm-1K-1, about half that of the mantle from which they are generated, and therefore partial melting of ascending mantle leads to a positive feedback that promotes high melt fractions. The chemical dependence of ksuggests that this effect may have been more or less effective on different planetary bodies and at different times in their evolution.

Fractional crystallization is an essential process proposed to explain worldwide compositional abundances of igneous rocks. It requires crystals to precipitate from the melt and segregate from its residual melt, or crystal fractionation. The compositional abundances of volcanic systems show a bell-curve distribution suggesting that the process has variable efficiencies. We test crystal fractionation efficiency in convective flow in low to intermediate crystallinity regime. We simulate the physical segregation of crystals from their residual melt at the scale of individual crystals, using a direct numerical method. We find that at low particle Reynolds numbers, crystals sink in clusters. The relatively rapid motion of clusters strips away residual melt. Our results show cluster settling can imprint observational signatures at the crystalline scale. The collective crystal behavior results in a crystal convection that governs the efficiency of crystal fractionation, providing a possible explanation for the bell curve distribution in volcanic systems.

During an extended volcanic unrest starting in 2017, two main moderate stratospheric eruptions occurred at the Ambae volcano (15°S and 167°E), Vanuatu, in April and July 2018. Observations from a geostationary orbit show that the April and July eruptions injected a volcanic plume into the lower stratosphere. While aerosol enhancements from the April eruption have only had an impact on the Southern Hemisphere, the plume from the July eruption was distributed within the lower branch of the Brewer-Dobson circulation to both hemispheres. Satellite, ground-based and in situ observations show that the background aerosol is enhanced throughout the year after the July eruption on a global scale. A volcanic-induced perturbation of the global stratospheric aerosol optical depth up to 0.012 is found, in the ultraviolet/visible spectral range. This perturbation is comparable to that of recent moderate stratospheric eruptions like from Kasatochi, Sarychev and Nabro. Top of the atmosphere radiative forcing values are estimated between -0.45 and -0.6 W/m2 for this event, showing that the Ambae eruption had the strongest climatic impact of the year 2018. Thus, the Ambae eruption in 2018 has to be taken into account when studying the decadal lower stratospheric aerosol budget and in climate studies.

Poor understanding of aerosol-cloud interactions and cloud feedback processes in the Arctic climate system limit our ability to constrain future climate in the region and one important knowledge gap is the source of particles upon which cloud droplets and ice crystals have formed. If representative cloud-water can be obtained from Arctic clouds, it’s chemical composition can be analysed to infer the sources of particles present within it. However, the balloon-borne active cloud water sampling systems required to obtain such samples have not previously been feasible due to their weight and the challenging environmental conditions. Here we present a miniaturised cloud-water sampler for balloon-borne collection of cloud water which was deployed during the Microbiology-Ocean-Cloud-Coupling in the High Arctic (MOCCHA) campaign in August and September 2018 along with the deployment protocol required to obtain representative samples in the pristine conditions encountered. We present the chemical composition of the samples obtained as well as the ice-nucleating activity of the samples and discuss the implications of our results on aerosol-cloud interactions in the high Arctic.

In this study, we present detrital zircon U-Pb dating and paleontological data for the newly identified Ayadeng formation in the northern margin of the North China Block (NCB) and Xibiehe formation (molasse) in the Bainaimiao Arc Belt (BAB), which could provide strong evidence indicating the affinity of the BAB and the evolution of the southeast Central Asian orogenic Belt (CAOB). Zircon U-Pb data of siltstone samples and paleontological data indicate the Ayadeng formation dates back to the early Ordovician. Although its location is near the NCB, its zircon grains’s age spectra and paleontology share a closer affinity with those of Tarim and NE Gondwana, as the U-Pb data suggest an age range of 778-1235 Ma, and similar gastropod fossils are found in Tarim and NE Gondwana. The U-Pb ages of meta-sandstone samples in the Xuniwusu formation indicate a shared inheritance with the Ayadeng formation (before 440 Ma), and the U-Pb ages of sandstone samples in the Xibiehe formation are concentrated, with age peaks centered at ca. 420Ma. Fossil corals occur in these two formations, and their sedimentary facies also indicate a collisional setting. Therefore, it is speculated that the BAB rifted from Tarim or NE Gondwana during the Ordovician and became attached to northern NCB between 440-420 Ma as an exotic terrane. During the early Paleozoic, there may have occurred a collision between an arc and a continental block.

On any given day, some region of the globe is likely to be affected by significant negative temperature anomalies. Depending on the severity, extreme cold periods may be deemed cold air outbreaks (CAOs). These CAOs can be detrimental to the agricultural industry and human health, especially in less prepared regions. A systematic CAO classification was developed using a set of criteria concerning magnitude, duration, and spatial extent from two gridded reanalysis datasets from 1979 – 2018. Trends in CAOs were calculated for different regions across the globe and the results from each reanalysis dataset compared with one another to identify discrepancies. CAOs were found to have decreased in spatial extent, frequency, duration, and magnitude across much of the globe, particularly across Alaska, Canada, and the North Atlantic, while an increase in CAOs was observed in Eastern Europe, Central Eurasia, and the Southern Ocean.

The ongoing coronavirus disease 2019 (COVID-19) pandemic has caused more than 150 million cases of infection to date and poses a serious threat to global public health. In this work, global COVID-19 data were used to examine the dynamical variations from the perspectives of immunity and contact of 85 countries across the five climate regions: tropical, arid, temperate, cold, and polar. A new approach is proposed to obtain the transmission rates based on the COVID-19 data between the countries with the same climate region over the Northern Hemisphere (NH) and Southern Hemisphere (SH). Our results suggest that the COVID-19 pandemic will persist over a long period of time or enter into regular circulation in multiple periods of 1-2 years. Moreover, based on the simulated results by the COVID-19 data, it is found that the temperate and cold climate regions have higher infection rates than the tropical and arid climate regions, which indicates that climate may modulate the transmission of COVID-19. The role of the climate on the COVID-19 variations should be concluded with more data and more cautions. The non-pharmaceutical interventions still play the key role in controlling and prevention this global pandemic.

Arctic sea-ice extent (SIE) has declined drastically in recent decades, yet its evolution prior to the satellite era is highly uncertain. Studies using SIE observations find little variability prior to the 1970s; however, these reconstructions are based on limited data, especially prior to the 1950s. We use ensemble Kalman filter data assimilation of surface air temperature observations with Last Millennium climate model simulations to create a fully gridded Arctic sea-ice concentration reconstruction from 1850–2018, and investigate the evolution of Arctic SIE during this period. We find a decline of ~1.25 x 106 km2 during the early 20th-century warming (1910-1940). The 25-year trends during this period are ~33-38% smaller than the satellite era (1979-2018) but almost twice as large as previous estimates. Additionally we find that variability of SIE on decadal timescales prior to satellite era is ~40% greater than previously estimated.

Variational data assimilation (VAR-DA) has been implemented to estimate the unknown input parameters of a new agricultural subsurface drainage model (SIDRA-RU) through assimilating discharge observations. The adjoint model of SIDRA-RU has been successfully generated by means of the automatic differentiation tool (TAPENADE). First, the adjoint model is used to explore the local and global adjoint sensitivities of the valuable function defined over the drainage discharge simulations with respect to model input parameters. Next, the most influential parameters are estimated by applying the VAR-DA embedded into a simple stochastic procedure in order to achieve the global minimum. The performed sensitivity analysis shows that the most influential parameters on drainage discharge are those controlling the dynamics of the water table; the second most influential parameters manage the starting date of the drainage season. Compared to an alternative gradient-free calibration performance, the estimation of these governing parameters by the VAR-DA method improves the overall quality of the drainage discharge prediction, in particular in terms of the cumulative water volume. Improved parameters generate less than 5 mm (1%) of the discrepancy between simulated and observed water volume, based on the five years of daily discharge observations on the Chantemerle agricultural parcels (36 ha). Preliminary numerical tests allow identifying the potential presence of local minima as well as equifinality issues. The latter can be highlighted by the self-compensation of both the physical soil parameters and the main conceptual parameters. Moreover, the proposed techniques may be applied to a panel of hydrological and water quality models.

The Australian 2019/2020 bushfires were unprecedented in both their extent and intensity, causing a catastrophic loss of habitat and human and animal life across eastern-Australia. Between October 2019 and February 2020 hundreds of fires burned, peaking in size in December and January and releasing the equivalent of half of Australia’s annual carbon dioxide (CO2) emissions. We use a high-resolution atmospheric-chemistry transport model to assess the impact of the bushfires on particulate matter with a diameter less than 2.5 µm (PM2.5) concentrations across eastern Australia. The health burden from short-term population exposure to PM2.5 is then quantified using a concentration response function. We find that between October and February an additional ~1.9 million people in eastern-Australia were exposed to ‘Poor’, ‘Very Poor’ and ‘Hazardous’ air quality index levels due to the fires. The impact of the bushfires on AQ was concentrated in the cities of Sydney, Newcastle-Maitland and Canberra-Queanbeyan during November, December and, also in Melbourne, in January. The health burden of bushfire PM2.5 across eastern-Australia, regionally and at city level is also estimated. Our estimate indicates that between October and February 171 (95% CI: 66 – 291) deaths were brought forward. The health burden was largest in New South Wales (109 (95% CI: 41 – 176) deaths brought forward), Queensland (15 (95% CI: 5 – 24)) and Victoria (35 (95% CI: 13 – 56)). At a city level the health burden was concentrated in Sydney (65 (95% CI: 24 – 105)), Melbourne (23 (95% CI: 9 – 38)) and Canberra-Queanbeyan (9 (95% CI: 4 – 14)), where large populations were exposed to high PM2.5 concentrations due to the bushfires.

The processes leading to the depletion of oceanic mesoscale kinetic energy (KE) and the energization of near-inertial internal waves are investigated using a suite of realistically forced regional ocean simulations. By carefully modifying the forcing fields we show that solutions where internal waves are forced have ~25% less mesoscale KE compared with solutions where they are not. We apply a coarse-graining method to quantify the KE fluxes across time scales and demonstrate that the decrease in mesoscale KE is a result of an internal wave-induced reduction of the inverse energy cascade and an enhancement of the forward energy cascade from sub- to super-inertial frequencies. The integrated KE forward transfer rate in the upper ocean is equivalent to half and a quarter of the regionally averaged near-inertial wind work in winter and summer, respectively, with the strongest fluxes localized at surface submesoscale fronts and filaments.