UNAVCO internships provide unique opportunities for students from underrepresented populations to develop their technical and communication skills while aiming to broaden participation in the Earth sciences. UNAVCO, a non-profit that operates the National Science Foundation-funded GAGE facility, has the opportunity to facilitate multiple internship programs, engaging students from across the United States. Prior to 2020, all internship programs were in-residence in Boulder, Colorado. Internship programs included project work and in-person professional development as well as cohort building, multi-level mentoring, and professional networking in the science-rich Boulder area. In light of the COVID-19 pandemic and ‘safer-at-home’ directives nationwide, we successfully converted our three internship programs to a remote format with fully online programming. We present our strategies for successfully planning, managing, and facilitating three online internship programs with 12 student participants ranging from community college to undergraduates to graduate students who all participated from their home locations. We also share our considerations for converting our internship programming to an online format, expanding our interns’ mentoring network and opportunities, and increasing our programs’ flexibility for interns who were personally impacted by national events. We present our process of identifying and engaging online learning experts and working collaboratively with all stakeholders to ensure each of our internships continued to be of the highest quality and our student experiences were not diminished. By offering the full length and robustness of our programs through a remote platform, we kept our promises of education, career advancement, monetary compensation, and community connection to our full 2020 intern cohort. In addition to offering geoscience projects and research experience to each intern, we implemented a robust suite of synchronous, online professional development courses that occurred weekly, including technical writing workshops, Geoscience Career Circles, and Communications Seminars focused on soft skill development. We also describe the support and training that we offered project mentors as they virtually guided students through successfully completing rigorous science projects and a suite of project deliverables including scientific posters, oral presentations, and technical manuscripts.

WW3 is a major spectral wave modeling system known for its applicability in large-scale modeling of sea states and wave climate from large rectilinear grids offshore to high-resolution unstructured grids in coastal zones, being widely used in operational, research and engineering arenas. Over the past few years, the operational global system at NCEP utilizes the multi-grid capabilities, where various rectilinear grids are nested internally to represent the offshore domain with a less computationally expensive coarse grid while the nearshore is run at a high-resolution grids. Alternatively, a single unstructured grid can be used for such applications. Recent advances in the performance of the model on unstructured grids provide the opportunity to run the model on large unstructured grids efficnetly. Here, an assessment of the operational global setup and unstructured wave models on various resolutions are given. The sensitivity to global unstructured mesh design was investigated using triangular meshes with a global minimum element size that ranged from 1.5 km to 6 km with local mesh refinement in storm landfall location. The validation is performed against satellite altimeter data and offshore NDBC network during normal and stormy conditions. We demonstrate that an optimized unstructured WW3 can be used for global applications, with superior performance relative to the complicated multi-grid system.

Southern California has seen a resurgence of winegrowing regions in the past few decades, however the future of winegrape climatic suitability in the area has not been exhaustively explored. This study evaluated the future climate suitability for the cultivation of winegrape and potential global warming impacts on southern California’s winegrowing regions through a series of high-resolution surface air temperature and precipitation projections obtained with the WRF-SSIB regional climate model. Results reveal that by mid-21st-century the surface air temperature will increase by approximately 1.2 °C, while average precipitation will decrease by as much as 11% in the southern winegrowing areas under the Intergovernmental Panel on Climate Change high greenhouse-gas emissions scenario. Evaluation of bioclimatic suitability indices indicate increases in heat accumulation for all major winegrowing areas; including an increase of about 10% in growing-degree day, while morning low temperatures in September may experience increases of approximately 11% in the future, thus impacting negatively the ripening stage of grapevines and leading to changes in wine composition and quality. Additionally, the extent of areas classified under the cool to warm climate suitability categories could decrease by nearly 42% in the study area by 2050. Conditions in southern California are already warm and dry for viticulture and continuing heat accumulation increase, along with rainfall reduction, could potentially place additional stress to winegrape crop in the area, including advanced phenological timing and moisture deficit stress that could lead to decreases in yield. The projected decline in viticulture suitability highlights the need for adaptive capacity within this sector to mitigate the impacts of global warming. Possible mitigating strategies include planting hotter climate grape varieties, moving vineyards to regions that are more suitable in the future, and adopting dry-farming techniques.

Public health communication strategies, including entertainment-education, can effectively change human behavior, improving health outcomes from climate change. Tools from social psychology, including social modeling and building self and collective efficacy, can help us to create a new model for current, culturally-relevant stories that can help communities adapt to climate change. As an example we will share key learnings from Rhythm and Glue, an applied television prototype, based on research from an NSF Advancing Informal STEM Learning submission. Best practices for climate communication include adaptations of entertainment-education techniques for culturally grounded representations of climate engagement positive outliers. As science communication progresses in adapting social psychology and sociology practices for climate communication, we would like to share how this prototype applies the methods and suggests some new directions that further adapt the practices to account for limited resources and media fragmentation challenges. While this work focuses on climate, it has broad implications for future science communication practices.

Most hydropower utilities rely on flow forecasts to manage the water resources of their reservoir systems and to help marketers and schedulers make efficient use of power generating resources. Flow forecast providers and dam operators typically assess the value of flow forecasts by assessing the skill of the forecasts in a verification exercise. Although there are many flow forecasting approaches available—from physics-based approaches associated with statistical pre and post processors and data assimilation, to emerging machine-learning based approaches—there is little consensus on how to choose the best forecast product. Nor are there established methods for translating forecast skill—a summary statistic amalgamating multiple types of errors —to forecast value (benefits or avoided cost) as perceived by a marketer or scheduler. In this work we develop such an approach by combining a water resources management model with a power grid model. Flow forecasts are developed at 85 locations for a varying range of skills, from perfect, to persistent and in-between. Using reservoir and power grid simulations over the Western U.S., we propagate flow forecasts through the power grid model, mapping flow forecast skill to regional hydropower revenues, production costs and carbon emissions. We develop a deeper understanding of the influence of regional and seasonal differences in markets and hydrologic dynamics on forecast value. We discuss future research directions to integrate hydrologic forecasts into decision-making at the utility and wider system scale.

The transport effectiveness of a stream flow event of a certain magnitude in carrying a sediment load is defined as the product of the effect of that event and the frequency with which it occurs. This approach is famously known as Magnitude-Frequency Analysis (MFA). MFA has been commonly used to calculate “effective discharge” which is considered as the stream flow that is responsible for transportation of the majority of the sediments from a river basin over a long period of time. In MFA, the stream flow at a location is assumed to follow a continuous probability distribution whereas the sediment transport is described by a rating curve between stream flow and sediment load. Despite the apparent good fit to the data, there are problems using a rating curve to predict sediment load. The sediment load carried through a stream network can be affected by the variability in stream flow occurring during different months or seasons (i.e. time scales) and consequent hysteresis phenomenon. Prediction of sediment load can be improved by constructing separate rating curves for various time scales. In this study, daily stream flow was assumed to follow the log normal distribution, and rating curves (between stream flow and sediment load) have been developed for total, monsoon, individual months data and considering hysteresis phenomenon for total and monsoon data in transport of sediments. Finally, MFA based effective discharges were calculated at 16 stream gauges in the Godavari River basin, India. The results of this study can find use in the effective planning and functioning of dams/reservoirs.

Whistler-mode waves have often been proposed as a plausible mechanism for pitch angle scattering and energization of electron populations in the solar wind. Theoretical work suggested that whistler waves with wave vectors parallel to the interplanetary magnetic field must counter-propagate (sunward) to the electrons for resonant interactions to occur. However, recent studies reveal the existence of obliquely propagating, high amplitude, and coherent waves consistent with the whistler-mode. Initial results from a particle tracing simulation demonstrated that these waves were able to scatter and energize electrons. That simulation was limited and did not examine a broad range of electron distributions. We have adapted the original particle tracing code for the solar wind with wave parameters observed by the STEREO satellites and to model core, halo and strahl electrons. Simulations are run to record the response of a wide initial phase space volume with uniform waves and wave packets. Using a Hamiltonian analysis, resonant responses at different harmonics of the cyclotron frequency are included in the simulation. A numerical integration scheme that combines the Hamiltonian analysis and the relativistic 3d particle tracing deployed on a high performance cluster enables accurate mapping and large-scale statistical studies of phase space responses. Observations of electron distributions from WIND at 1 AU are used for normalization. This enables extrapolations for core, halo, and strahl electrons evolution with the numerical Green’s function method. Results provide evidence for pitch angle broadening of the strahl and energization of core and halo electrons. This model can also provide results that are applicable to a number of different wave-particle interactions in the heliosphere for comparison to in-situ measurements.

Transport and retention behavior of Graphene Oxide (GO) is influenced by the physical and chemical properties of porous media under subsurface environmental conditions. Fixed-bed column studies using quartz sand and biochar (BC) in different configurations were conducted as a function of ionic strength and flowrate. Colloid filtration theory (CFT) was employed to develop mathematical models based on the one-dimensional convection-dispersion equation using experimental GO breakthrough curves (BTCs) and retention profiles (RPs) obtained from the experimental data. GO transport and retention behavior was modeled using BC and BC-nZVI (BC surface modified with nanoscale zero-valent iron) as filter media to understand the effect of media properties. It was demonstrated that the model can describe measured BTCs and RPs of GO in the sand, BC, and BC-nZVI. The inverse modeling approach was implemented to determine the attachment coefficient (Ka) and maximum solid-phase retention capacity (Smax) using GO BTCs for different experimental conditions. Higher Ka in BC at 10 mM IS indicated the influence of straining which agrees with the depth-dependent retention kinetics. Furthermore, pronounced GO aggregation at higher IS supports the higher Ka values at 10 mM compared to 0.1 mM. In contrast, higher Ka values were predicted in BC-nZVI at lower ionic strength (0.1 mM) primarily due to the attachment of GO onto nZVI where nZVI in BC pores was also favorable for the straining process. This study revealed that CFT including the attachment, straining, and blocking process can effectively describe the GO transport in BC and surface-modified BC-nZVI under subsurface environmental conditions.

Marine cloud brightening (MCB) is the idea that the amount of solar radiation reflected by low clouds might be deliberately increased by augmenting the existing population of aerosol particles with salt particles created from seawater. MCB has been suggested as one of the potentially feasible climate intervention approaches to counteract anthropogenic global warming. Global and process modeling studies have been conducted to assess various aspects of MCB, but many questions remain. Observations evaluating the brightening of clouds using pollution from commercial shipping serve as a useful tool for evaluating potential for brightening, as do studies using detailed microphysical models and large eddy simulations. In this presentation, these different pieces of knowledge will be synthesized using the framework of a simple heuristic model, which aims to estimate bounds on the global radiative forcing possible from MCB given assumptions regarding: (a) the quantity, size, and lifetime of salt particles injected from each vessel; (b) the number of vessels deployed; (c) the relationship between cloud droplet concentration and the aerosol size distribution; (d) the albedo susceptibility of clouds; (e) the strength of the cloud liquid water adjustments to aerosol. This presentation will use the heuristic model to explore questions such as: How much salt mass must be sprayed to achieve a certain forcing, what is the optimal size for the injected particles, and how many ships are really needed to achieve significant cooling?

Serpentinites play a vital role in subduction zone processes: as one of the dominant carriers of water in downgoing plates, they are critical constituents in the global volatile cycle and add complexity to the bulk rheology and density of downgoing and overlying plates, with strong implications for seismicity and mechanical mixing. These rocks can form in a number of tectonic settings where water reacts with peridotite under certain conditions, including at or near mid-ocean ridges and in mantle overlying dehydrating subducted plates. In the HP/LT terrane preserved on the island of New Caledonia, serpentinites outcrop as meter-scale resistant blocks and as highly deformed “matrix” that hosts a range of metasedimentary, metamafic, and meta-ultramafic lenses. The origin of these HP serpentinites has been debated, with competing hypotheses linking protolith to nearby obducted ophiolite or to the subducted oceanic plate. We analyzed 30 serpentinites and associated hybrid rocks from across the HP terrane to discern the tectonic origin of their protoliths and to better understand their reaction history through subduction and exhumation. Whole rock major and trace element and stable isotope geochemistry reveal the existence of at least two distinct types of serpentinites in the HP terrane. Serpentinites in the far NE exhibit elevated HREE’s, δ18O values of 6-10‰, and scatter in major element concentrations. In the SE, a ~1 km2 ultramafic massif contains serpentinites with relatively more depleted REE, δ18O values of 5-7‰, and a more restricted range of major element concentrations, with distinctly higher MgO and lower Al2O3 than samples from the NE. We compare these data to a global geochemical compilation of serpentinites from various tectonic settings. Ongoing Raman spectroscopy work will determine serpentine polymorph(s) and electron probe microanalysis will target isolated relict pyroxene grains and oxide minerals to retrieve additional protolith information. The recognition of multiple types of serpentinites in this HP/LT terrane adds important information to debate about the origin of the ultramafic material, and may speak to complex interactions between the downgoing plate and overlying mantle or to systematic spatial differences in protolith composition or degree of metamorphism or deformation.

A three-color, extremely high signal to noise, precisely pointed, sub-arcsecond photometer would enable us to distinguish Earth-like exoplanets from other rocky, gassy, or icy worlds - if we had the right three wavelengths, and the ability to block out the primary star’s glare. Color-color discrimination of Earth-like planets has been posited for quite some time. Broadband filters are not seen to be precise diagnostics of planets with life, but rather broad but critical similarity or difference to the one habitable planet we know. Visible wavelengths (Vis) are advantageous due to relatively greater abundance of photons of that wavelength range from planets around Sun-like stars. Near-ultraviolet (UV) wavelengths may be advantageous due to ozone and scattering properties in Earth’s atmosphere that make Earth truly stand out from other known and modeled planets. Near infrared wavelengths (IR) help discriminate potential biological color contributions. We conducted an optimization exercise to arrive at three broadband filters that reliably separate modeled Earth-like, nominally habitable planets from other possible exoplanets. Criteria we use included: - Atmosphere/clouds of habitable worlds - Sea/Land proportions (ocean, granite, basalt, other surface material) - Vegetation (chlorophyll spectra and fictional other photosynthetic materials depending on wavelengths of parent stars etc.) - Other factors that can be spectrally modeled (planet-covering cities, world oceans, etc.) The optimized bands resemble previous work for exoplanets and the solar system, but underscore the advantage of UV wavelengths and indicate their potential utility for exoplanet identification and/or discrimination in concert with other exoplanet observations. An exoplanet survey that could quickly identify such planets could then be followed up by more detailed, longer term study by more intensive campaigns with more capable, but more resource or time constrained.

Since the famously inconclusive Viking missions, we have observed an increased desire to discover life outside the Earth. However, if we are to plan effective life-detection missions, then we must meet the challenge of classifying potential “agnostic” biosignatures (indicators of life or the absence of life). Agnostic refers to attempting to not use biosignatures that would bias towards Earth centric life standards, which would be “putting the answer in the question.” Machine learning techniques, specifically statistical classification already showed promising results in other fields. Applied to astrobiology, it may provide clarity on how different and independent measurements of the same biosignature affects your confidence in whether it is indicative of life. In this work, these algorithms were implemented to classify Raman spectra of potential biosignatures. Data was collected from public databases and individual research papers, processed, and then evaluated with several different algorithms. After thousands of simulations to allow the algorithms to test their classifications, we observed an 81% probability of correct classification when all the algorithms’ individual predictions were combined. These results demonstrate Raman spectroscopy’s potential for life-detection missions, and ability to improve upon a qualitative criterion for identifying indicative of life biosignatures.

Conductivity of the ionosphere allows the complex system of magnetospheric currents to flow through. Conductivity is governed by several factors including electron density and temperature, whose influence is highly dynamic during geomagnetic storm events. Thus, it is a crucial parameter that must be determined for space weather modeling to specify the coupling between the magnetosphere, ionosphere and thermosphere systems. Major sources of ionospheric conductivity are solar EUV and particle precipitation which includes Diffuse (Diff.), Monoenergetic (ME) and Broadband (BB) precipitations. Conductance Σ is the height integrated version of conductivity. Empirically, total ionospheric conductance (Hall and Pedersen) is known to be the root sum square of individual conductance terms [Wallis and Budzinski, 1981], considering that conductivity resulting from different processes are not linearly additive and corresponding ionization rates shall be added at each altitude and then integrated over the desired altitude range. With the inclusion of the less energetic broadband precipitation that was found to cause ionization in the bottom-side F region, the expression for the total ionospheric conductance was modified by the linear addition of the contribution of the broadband precipitation to the total Hall and Pedersen conductance[Zhang et al., 2015].In this study, using a 3-dimensional global physics based model GITM (Global Ionosphere Thermosphere Model), the validity of this combination of vector and linear addition of individual source terms to the total ionospheric conductance is examined and the more accurate expression for the summation of sources contributing to the total conductance is quantified. GITM is employed to calculate the Hall and Pedersen conductance using the average energy, potential and energy flux for each of the sources of conductance. Several scenarios are simulated where the different sources of precipitation are paired with solar EUV radiation, and the total conductance is obtained. Linear and vector summation of conductance resulting from combinations of sources and individual sources indicate that the contribution of broadband precipitation to the total conductance also follows vector addition. To quantify the result that the total conductance is the vector sum of individual sources, error histograms are plotted and a set of metrics including RMSE, mean error, standard deviation, correlation coefficient and fractional error are enumerated for both linear and vector summation of individual sources to produce the total conductance.

New relative paleointensity results from mafic lava flows erupted in quick succession during four Neogene geomagnetic reversals show that volcanic transition zones can provide a favorable setting for the pseudo-Thellier technique. The most compelling data are from a normal-to-reverse (N-R) transition zone in the 4 my old basaltic lava flows of the Olokele Formation on Kauai (Hawaii). Following stepwise alternating field (AF) demagnetization of each sample’s natural remanent magnetization, an anhysteretic remanent magnetization (ARM) was imparted in a 50 uT bias field and then AF demagnetized. Very similar behavior of the 35 mT to 90 mT coercivity fractions suggest that the NRM (interpreted to be a primary thermoremanent magnetization (TRM)) and ARM reside in the same subpopulation of magnetic grains. With the ARM intensity serving as an analog for TRM susceptibility, the 35 mT-90 mT TRM/ARM ratios provide a relative measure of the ancient field intensity. Good correlation of flow-mean TRM/ARM ratios with a small set of double-heating paleointensities from companion samples allows an approximate scaling of the TRM/ARM ratios to absolute intensity. As the geomagnetic polarity switched, the field strength apparently dropped by 91% compared to the maximum recorded by the flows. This decrease is comparable to that observed in other paleomagnetic studies and numerical simulations. During an interval of NE-down directional stasis recorded by a succession of 10 flows in the lower half of the section, the geomagnetic intensity rose to over 20 uT and then decreased to near 5 uT. This distinctive behavior could mark the waxing and waning of a stationary, inward-directed flux patch on the core mantle boundary centered NE of Kauai. Within-flow variability of relative paleointensity was higher in two other Pliocene transition zones on Kauai (both R-N), and in the R-N transition recorded by 15.2 my old lavas in the Sheep Creek Range (Nevada). Nevertheless, all three records document a reduction in the ancient geomagnetic field intensity similar in magnitude to that seen in the Olokele flows. The relative uniformity of magnetic mineralogy may help explain why the pseudo-Thellier technique was able to capture the large transitional intensity changes recorded by these rapidly-erupted flow sequences.

Tomographic analysis of Pn arrivals times—the guided P-wave propagating within the lithospheric mantle—is ideal for studying the structure of the uppermost mantle. While plate-scale seismic images of Pn wave speeds are common beneath the continents, similar scale studies have not been possible within ocean basins due to the sparsity of seismic stations. The Cascadia Initiative (CI) dataset provides the first opportunity to image spatial variations in lithospheric structure across an entire oceanic plate. We measure 2,862 Pn arrivals from local earthquakes recorded by the CI array. Our dataset provides complete coverage of both the Juan de Fuca (JdF) and deforming Gorda plates. We invert the measured arrival times for 3D variations in anisotropic P-wave velocity and hypocentral parameters. Despite surficial evidence of extensive active faulting, the velocity structure of the Gorda uppermost mantle is remarkably consistent with predictions from a conductive cooling model (attached figure). Limited deformation at mantle depths is supported by seismic anisotropy measurements that show the fast-direction of P-wave propagation rotates in concert with the magnetic anomaly lineations. This rotation may be explained by local plate kinematics without internal deformation and hydration of the shallow mantle. In contrast to Gorda, the seismic velocity structure of the JdF plate does not exhibit a clear age dependence. Three pronounced mantle low-velocity zones are found along the southern edge of the JdF plate near the termini of large pseudofaults that contributed to the formation of the Blanco Transform fault. We attribute these velocity reductions to mantle alteration by seawater. We note that within the interior of the JdF plate pseudofaults do not appear as uniformly slow features in our seismic images. Beneath the central and northern JdF plate, P-wave speeds are ~7.7 km/s out to ~4-5 Myr before abruptly increasing to ~7.9 km/s. Curiously, this transition occurs near the onset of mantle downwelling inferred from teleseismic body wave tomography and attenuation suggesting that mantle flow dynamics may influence the structure of young oceanic lithosphere. Lastly, we note that our results do not suggest a relationship between the structure of the uppermost slab mantle and segmentation of the Cascadia megathrust.

As Earth System Science (ESS) becomes more data-intensive, collaborative, and interdisciplinary, it is important to understand how best to support and advance data reuse. We conducted an online survey of active ESS researchers from 126 U.S. universities and research centers, representing a wide variety of scientific fields. Of the 207 respondents, 51.7% had more than 20 years of research experience. Results indicated that the current primary purposes for reusing data are to conduct new analysis (87%), followed by comparing results (70.4%), with only 18.5% reusing data to reproduce published studies. As expected, data hosted by federally funded data centers were reused most frequently, with open government data and data provided directly from other researchers also widely used. Reuse of data from other types of repositories lags far behind, due in part to a range of service limitations. At the same time, data sharing by respondents is strong—96.6% actively release their data, primarily as supplements to published papers, with moderate use of open access repositories. Of the 45.9% who had attempted to reproduce research, 73.7% failed at least once, often due to the limited detail provided in published papers. Still, 92.3% believe it is the researcher’s responsibility to ensure their work is reproducible. The majority favored traditional modes of documenting research—word processors, text editors, and code commenting over electronic notebooks or workflow systems. Interestingly, 59.9% continue to use hand-written notebooks. Challenges to data reuse and reproducibility specific to ESS included the complex nature of earth systems, increasingly complicated models, lack of data management resources, and limited emphasis on reproducibility in the field. Open-ended responses raised questions about whether “exact replication” is necessary or possible for ESS. Most researchers agreed that data and code should be considered important research products and that outlets are needed for publishing negative results. Taken together, the results suggest a strong data sharing culture in ESS with high levels of reuse and commitment to open science. The research community would benefit greatly from better documentation and sharing of methods and research processes, as well as targeted improvements in data services and tools.

During the mid-Holocene (MH, 6,000 years BP), precessional forcing drove enhanced monsoon rainfall, expanded vegetation cover, and reduced dust emissions throughout the African Sahara. The orbital forcing and feedback of vegetation albedo have been widely studied with climate models, but are found to be insufficient to explain the magnitude and location of rainfall anomalies suggested from proxy reconstructions. The feedback of reduced Saharan dust loading has been less-studied because Paleoclimate Modelling Intercomparison Project (PMIP) Phase 2/3 models did not incorporate the decreased MH Saharan dust emissions. Several recent modeling studies investigated the MH Saharan hydroclimate response to reduced dust loading; however, their models only resolved the direct effect from dust aerosols (i.e. direct radiative forcing), which leaves the contribution from indirect dust aerosol effects (i.e. dust aerosol-cloud interactions) largely unknown. Here we investigate the hydroclimate response due to Saharan dust using CESM CAM5-chem, which includes both the direct and indirect dust aerosol effects. In the simulations, reduced Saharan dust directly increases monsoon season (JJAS) net shortwave radiative flux at the surface, which drives continental warming. Convective clouds and convective precipitation are subsequently enhanced and, due to the overwhelming convective nature of this monsoonal region, total Saharan (20–31°N, 20°W–30°E) precipitation increases by 11.9%. However, indirect dust aerosol effects counteract the increase from convection precipitation. A reduction in Saharan dust decreases cloud nuclei number concentration and increases cloud droplet size, which in turn reduces stratus cloud cover and large-scale stable rainfall. Overall, the decrease in large-scale stable rainfall due to indirect dust effects reduces total precipitation by 12.5%. The total rainfall increase of 0.27 mm/day from reduced dust is significant but smaller than the response to changes in vegetation cover (1.19 mm/day). While these results indicate that less Saharan dust during the MH likely enhanced Saharan rainfall, they also suggest that a reduction in the indirect effects of dust likely dampened the overall response of rainfall to the MH dust forcing.

In 2007, the National Academies designated “understanding the structure & composition of the lunar interior” (to provide fundamental information on the evolution of a differentiated planetary body) as the second highest lunar science priority that needed to be addressed. Here we present the current status of the planned response of the Lunar Geophysical Network (LGN) team to the upcoming New Frontiers-5 AO. The Moon represents an end-member in the differentiation of rocky planetary bodies. Its small size (and heat budget) means that the early stages of differentiation have been frozen in time. But despite the success of the Apollo Lunar Surface Experiment Package (ALSEP), significant unresolved questions remain regarding the nature of the lunar interior and tectonic activity. General models of the processes that formed the present-day lunar interior are currently being challenged. While reinterpretation of the Apollo seismic data has led to the identification of a lunar core, it has also produced a thinning of the nearside lunar crust from 60-65 km in 1974 to 30-38 km today. With regard to the deep mantle, Apollo seismic data have been used to infer the presence of garnet below ~500 km, but the same data have also been used to identify Mg-rich olivine. A long-lived global lunar geophysical network (seismometer, heat flow probe, magnetometer, laser retro-reflector) is essential to defining the nature of the lunar interior and exploring the early stages of terrestrial planet evolution, add tremendous value to the GRAIL and SELENE gravity data, and allow other nodes to be added over time (ie, deliver the International Lunar Network). Identification of lateral and vertical heterogeneities, if present within the Moon, will yield important information about the early presence of a global lunar magma ocean (LMO) as well as exploring LMO cumulate overturn. LGN would also provide new constraints on seismicity, including shallow moonquakes (the largest type identified by ALSEP with magnitudes between 5-6) that have been linked to young thrust fault scarps, suggesting current tectonic activity. Advancing our understanding of the Moon’s interior is critical for addressing these and many other important lunar and Solar System science and exploration questions, including protection of astronauts from the strong shallow moonquakes.