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Community-curated data resources in the Earth sciences, highly valuable but systematically underfunded, are vital to research on a changing planet. 

  Widespread concern about the “decline of taxonomy” has motivated calls to action to re-invigorate the field by enhancing taxonomic training, along with increasing taxonomy funding and positions, improving citation rates, and describing species more rapidly. Taxonomic training has historically been apprentice style, with individuals training for years under expert guidance. This approach offers a rich learning experience but inherently limits trainee number and relies on students’ earlier exposure to taxonomy. We describe a scaled-up taxonomic training model using a Course-based Undergraduate Research Experience (CURE) to provide early taxonomy research experience and broadly applicable scientific research skills. Results from a 45-student taxonomy-focused course conducted concurrently at 2 universities resulted in increased interest in taxonomic revisions and ability to explain taxonomic concepts, with one-third of students developing more interest in taxonomic careers. General science skill development was high when compared to a large sample of other CURE courses. The research focus of the course was taxonomic revision of the ant genus Nylanderia in Meso-America; students worked with instructors to delimit and describe new species. Here, we present 4 newly described species: Nylanderia ambulator, sp. nov. Nylanderia aurantia, sp. nov., Nylanderia collaborans, sp. nov., and Nylanderia maximon, sp. nov., with an additional 13 putative species noted for further revisionary work. This expanded taxonomic training model combines hands-on research experience with peer-learning and caters to students with minimal exposure to taxonomy. As a result, this approach broadens recruitment to more diverse audiences and results in enhanced awareness of and appreciation for taxonomy. 

Globally, potentially hundreds of Nylanderia species remain undescribed, hidden within several broadly distributed complexes of morphologically cryptic species. By integrating phylogenomics, geography, and morphology, we describe eight new Nylanderia species from southern Mexico and Mesoamerica, increasing the total number of known species in the genus to 131. In the Americas, Nylanderia is divided into two distantly related clades: American Clade I (AC1) and American Clade II (AC2). Within AC1, Nylanderia austroccidua (Trager) was originally described as a widespread and morphologically variable species distributed from Utah to Costa Rica. This species was diagnosed by a slight concavity in the anterior face of the pronotum and varying degrees of fine cuticular microsculpturing across the body that causes blue cuticular iridescence under microscopic examination. Using Ultraconserved Elements (UCEs) for molecular phylogenetic analysis, we found that taxa matching the original description of N. austroccidua are paraphyletic with respect to Nearctic Nylanderia species. We also found that AC1 includes a Neotropical subclade extending into Mesoamerica, the distribution of which overlaps with AC2, which is exclusively Neotropical. Along with an updated description of N. austroccidua, we also describe the following new species belonging to clade AC1: N. breviscapa, sp. nov., N. contraria, sp. nov., N. lazulina, sp. nov., N. luceata, sp. nov., N. mendax sp. nov., N. mosaica sp. nov., N. polita sp. nov., and N. usul, sp. nov. A dichotomous key and images of the worker caste of these species are included and, where available, images of queens and males are provided.  

Climate and ecosystem dynamics vary across timescales, but research into climate-driven vegetation dynamics usually focuses on singular timescales. We developed a spectral analysis–based approach that provides detailed estimates of the timescales at which vegetation tracks climate change, from 10¹to 10⁵years. We report dynamic similarity of vegetation and climate even at centennial frequencies (149⁻¹to 18,012⁻¹year⁻¹, that is, one cycle per 149 to 18,012 years). A breakpoint in vegetation turnover (797⁻¹year⁻¹) matches a breakpoint between stochastic and autocorrelated climate processes, suggesting that ecological dynamics are governed by climate across these frequencies. Heightened vegetation turnover at millennial frequencies (4650⁻¹year⁻¹) highlights the risk of abrupt responses to climate change, whereas vegetation-climate decoupling at frequencies >149⁻¹year⁻¹may indicate long-lasting consequences of anthropogenic climate change for ecosystem function and biodiversity. 

Abstract. The Indo-Pacific Pollen Database (IPPD) is the brainchild of the late Professor Geoffrey Hope, who gathered pollen records from across the region to ensure their preservation for future generations of palaeoecologists. This noble aim is now being fulfilled by integrating the IPPD into the online Neotoma Palaeoecology Database, making this compilation available for public use. Here we explore the database in depth and suggest directions for future research. The IPPD comprises 226 fossil pollen records, most postdating 20 ka, but some extending as far back as 50 ka or further. Over 80 % of the records are Australian, with a fairly even distribution between the different Australian geographical regions, the notable exception being Western Australia, which is only represented by 3 records. The records are also well distributed in modern climate space, the largest gap being in drier regions due to preservation issues. However, many of the records contain few samples or have fewer than 5 chronology control points, such as radiocarbon, luminescence or Pb-210 for the younger sequences. Average sedimentation rate for the whole database, counted as years per cm, is 64.8 yr/cm, with 61 % of the records having a rate of less than 50 yr/cm. The highest sedimentation rate by geographical region occurs on Australia’s east coast, while the lowest rates are from the Western Pacific. Overall, Australia has a higher sedimentation rate than the rest of the Indo-Pacific region. The IPPD offers many exciting research opportunities, such as examination of human impact on regional vegetation, contrasting first human arrival and colonisation, and assessment of rates of vegetation change during the Holocene. Merging the IPPD into Neotoma also facilitates inclusion of data from the Indo-Pacific region into global syntheses. 

In this paper, we share the experience of the U.S. National Science Foundation (NSF) National Solar Observatory (NSO) scientists, educators, and public outreach officers in organizing an eclipse viewing party within a stadium at a sports complex on the US/Mexico border in Eagle Pass, TX in collaboration with educators from the Eagle Pass and the Uvalde areas. We describe the reasons we chose Eagle Pass, contacts we established with the local community, preparations for and activities set up during the eclipse viewing party, the eclipse day on April 8, 2024, and lessons learned from organizing our event. 

Abstract Hailstorms cause billions of dollars in damage across the United States each year. Part of this cost could be reduced by increasing warning lead times. To contribute to this effort, we developed a nowcasting machine learning model that uses a 3D U-Net to produce gridded severe hail nowcasts for up to 40 min in advance. The three U-Net dimensions uniquely incorporate one temporal and two spatial dimensions. Our predictors consist of a combination of output from the National Severe Storms Laboratory Warn-on-Forecast System (WoFS) numerical weather prediction ensemble and remote sensing observations from Vaisala’s National Lightning Detection Network (NLDN). Ground truth for prediction was derived from the maximum expected size of hail calculated from the gridded NEXRAD WSR-88D radar (GridRad) dataset. Our U-Net was evaluated by comparing its test set performance against rigorous hail nowcasting baselines. These baselines included WoFS ensemble Hail and Cloud Growth Model (HAILCAST) and a logistic regression model trained on WoFS 2–5-km updraft helicity. The 3D U-Net outperformed both these baselines for all forecast period time steps. Its predictions yielded a neighborhood maximum critical success index (max CSI) of ∼0.48 and ∼0.30 at forecast minutes 20 and 40, respectively. These max CSIs exceeded the ensemble HAILCAST max CSIs by as much as ∼0.35. The NLDN observations were found to increase the U-Net performance by more than a factor of 4 at some time steps. This system has shown success when nowcasting hail during complex severe weather events, and if used in an operational environment, may prove valuable. 

Abstract A key issue in the development of theory and models for plasma propulsion devices is to describe the instabilities and fluctuations of the devices. It has been widely recognized that many Hall effect thrusters (HETs) exhibit oscillations at frequencies in the range of ∼ 20 kHz. These ionization-related oscillations are generally referred to as Breathing Mode oscillations and have been the subject of considerable research. Here, for the first time, we report direct temporally resolved measurements of the ground state neutral density variation during the period of the oscillation. We used the laser-based Two-Photon Absorption Laser Induced Fluorescence (TALIF) technique to measure neutrals within the plume of a 1.5 kW HET operating on krypton (Kr). Our TALIF scheme employs a frequency-doubled, pulsed dye laser operating at ∼ 212 nm to probe ground state Kr atoms. A novel phase-binning approach is used to recover the time-dependent signal by assigning the timing of each collected TALIF signal (laser shot) relative to the phase of the discharge current. We find that the neutral density fluctuates quite strongly over the period of the oscillation, and that this fluctuation leads the current fluctuation as expected.