A system capable of reliably detecting catastrophic landslides and centimeter movement in land mass could save lives and offers landowners valuable information about gradual changes in soil displacement on their land. With precise acceleration and relative positioning data collected from an accelerometer and a set of GPS receivers, a system can be designed to detect subtle changes in sensor position due to land movement. With the rapid production of new microprocessors and greater memory storage capabilities the limits of microcontroller systems are continually expanding. The Slide Sentinel project offers landowners a low-cost alternative to commercial equipment consisting of a network of remote low power sensors that detect fast linear slides and eventually lower soil movements such as creep. Long range low-power (LoRa) radio connections on these sensor nodes wirelessly transmit three-dimensional acceleration, Real Time Kinematic (RTK) GPS coordinates, and sudden shift alerts to a common base station where they are exported to an online spreadsheet to be processed remotely.

Several winters of the 2010s have brought to many midlatitude regions periods of extreme cold relative to the past few years and even decades. Further, it is suggested that melting of Arctic sea ice has increased the likelihood of persistent extreme weather conditions in the northern midlatitudes and the number of cold winter days. Here, estimates of warming in annual minimum temperature are updated and extended to all land areas where station temperature records are available, with emphasis on the midlatitudes. Annual minimum temperatures have warmed faster than mean temperatures in seasonally cold land regions and have already exceeded a 2 K warming threshold over the midlatitudes, but have warmed at about the same rate as mean temperatures in tropical climates. Recent regionally cold winters did not significantly deviate from the established warming trend and were within the range of interannual variability seen in the past. These findings have implications for contextualizing extreme winter weather, validating climate model projections of the consequences of sea ice loss, and guiding adaptation to shifting hardiness zones of perennial cultivars and the spread of pest and invasive species.

Unmanned aerial vehicles (UAV) have been increasingly used for field data collection and remote sensing purposes. Their ease of use, ability to carry sensors and cameras, low cost, and precise maneuverability and navigation makes them a versatile tool for a field researcher. Procedures and instrumentation to use UAVs in the field are largely undefined, especially for atmospheric and hydrologic applications. A field study was conducted to test the UAV’s ability to collect atmospheric data in order to locate and analyze the canopy boundary layer (CBL) above a Costa Rican tropical montane rainforest. This study aims to give further insight on the changes of the CBL throughout the day and for atmospheric comparison to land development. Through the study, it was found that there was little previously defined procedures and preferred instrumentation that directly applied to the UAV field study. Because of this, the methodology of using an UAV for atmospheric and CBL remote sensing and data collection was developed and refined by testing and comparing precision and performance of sensors and executing systematic flight patterns throughout the day. The UAV allowed for quick and specific access to sampling locations and for all of the variables to be measured by sensors over vertical profiles. Flights were scheduled at different locations throughout the day over the Texas A&M Soltis Center and surrounding forest in San Isidro, Costa Rica. Vertical profiles were also measured over the Soltis Center grounds to determine how development has affected the presence of the CBL. The UAV was successful in gathering data above the forest canopy and the Soltis Center at varying elevations during clear and cloudy conditions. The procedure produced reliably consistent vertical profiles over small domains in space and time, validating the general approach. The technique also identified unique profiles at spatially and temporally distinct sample sites including response to meteorological events. These findings suggest a healthy ability to diagnose CBL characteristics of interest. It was also found that there is a distinct increase in temperature and dew point over land development when compared to over forest. Future studies include flights at other locations and determining preferred instrumentation for UAV atmospheric data collection.

Formal data citation is a growing practice increasingly required by scientific journals. Roughly a decade ago, the Federation of Earth Science Information Partners (ESIP) began developing formal guidelines for data citation including acknowledgement of authors and archives and careful use of persistent identifiers (PIDs). Many Earth science data centers now provide formal citation text and PIDs for their data sets, typically a Digital Object Identifier (DOI). A central purpose of data citation (amongst many) is to aid scientific reproducibility through direct, unambiguous reference to the precise data used in a particular study, i.e., to aid provenance tracking. How has that worked in practice? ESIP is now in the process of revising and updating their guidelines and seeks to ensure that data citation meets its stated purpose. This presentation explores whether and how formal citation and the the use of PIDs for data sets has improved the tracking of data provenance. For example, is there is some commonality in the nature and granularity of objects that are assigned PIDs? We review how the guidelines are being revised to further enhance the transparency and reusability of data.

The Younger Dryas (YD) in Bay of Islands, Newfoundland is characterized by major changes in both pollen and dinocyst assemblages, which translate into large drops in air and sea surface temperatures and sea surface salinity. Changes in vegetation are similar with those observed in Newfoundland lakes. Reconstructed air temperature shows a 7ºC drop at the time of the YD, an amplitude comparable to changes recorded in northeastern North America. Changes observed in dinoflagellate cyst assemblages are also like those at nearby sites from the Gulf of St. Lawrence and Laurentian Channel. Sea surface dropped by 7ºC, salinity by 4 psu and sea ice cover duration increased by 7 months. The YD period in eastern North America was traditionally defined by changes in sediments and pollen records. Our records show that the cooling in sea surface and air temperatures started 250 and 110 years before the start of the YD as defined by radiocarbon dates and pollen zones. By having exceptionally high resolution records for both terrestrial and marine conditions in the same core, we can show that there is a 140 years delay between ocean and atmosphere. We speculate that the major lithological and vegetation changes observed in lakes around the time of the YD period in eastern North America might actually represent the full impacts of the cooling, since the cooling trend actually started before the start of the YD period.

A new family of analytical magnetohydrostatic equilibria is presented. The methodology used to calculated these equilibria is based on work by Low (e.g. Low 1991) in the form given by Neukirch and Rastätter (1999). The equilibria have the capability of combining a non-force-free layer with a domain of linear force-free magnetic field, including a transition between these two domains. Potential applications to modelling solar magnetic fields will be discussed. Low, B.C., ApJ 370, 427 Neukirch, T. & Rastätter, L., A&A 348, 1000

Empirical Mode Decomposition (EMD) is used to examine the relationship between precipitation and surface temperature from six regions. Three regions are defined by physiography: world, ocean, and land. The other three regions are defined by averaged precipitation: dry, normal and wet. Monthly averaged daily precipitation rate from the Global Precipitation Climatology Project are compared with average monthly surface air temperature anomalies from the Goddard Institute for Space Studies using EMD. The EMD process produces component time series referred to as intrinsic mode functions (IMFs). Theses IMFs are ordered by frequency from high to low. Eight IMFs were produced for each the time series. The first three IMFs corresponded to seasonal, semi-annual and annual variations, respectively. IMF 4 to 6 corresponded to a biennial, pentennial and decadal climate signals, respectively. IMF 7 was related to the broad 20-30 year period, with the trend being revealed in IMF 8. The time series spanned the period from January 1980 to December 2015 at monthly intervals. Temperature and precipitation time series from six sampling regions were analyzed for evidence of correlation. Results from the analysis reveal the following: (1) The EMD process reveals both linear and non-linear trends. The trends are not entirely consistent between regions though they are highly correlated. (2) Apparent wave-to-wave interactions between high and low frequency components appear to be observed in the IMF 1 and 2. These distortions appear to correspond to the troughs and peaks in the decadal cycle captured in IMF 6 and may related to the solar cycle. (3) The correlation between precipitation and temperature increases with increasing IMF number.

Abstract: In Sichuan basin, the Longmaxi-Wufeng formation is rich of the shale gas, and the study of control factors of pores structure and connectivity are extremely significant for exploration of shale gas. Organic matter and inorganic matrix attribute to shale reservoir characters strongly. Though this work has been carried out by others before, it still has some arguments for this topic. In this project, we collected rock samples from oilfields, we did SEM, CO2 adsorption CH4 adsorption N2 adsorption, high pressure mercury injection, microscope observation, NMR, XRD, TOC test some related experiments. Analytical results show that TOC contents of the samples range from 0.96% to 6.12%, and the Wufeng-Longmaxi formation shale organic matter content is high. The samples porosity and permeability range from 0.49%-9.55% and 0.0006mD-0.73mD respectively, and the I/S of clay mineral amount ranges from 10%-60%. A plenty of graptolites were observed in the formation under microscope, and reflectivity of graptolites and solid bitumen can reveal that organic maturity is high in the formation. The higher the TOC percentage of sample, the higher the graptolite reflectance is. There are hydraulic fractures under microscope and SEM observation, and some of hydraulic fractures formed by stress, and some of them formed by hydrocarbon generation. Inorganic pores including bedding fracture, structural pores, intercrystalline pores, intergranular pores and dissolved pores and organic pore including corrosion pores, gas pores, bitumen spherulite pores can be observed. We observed quartz, calcite, feldspar under SEM to identify their cementation, filling, different periods’ growth, and aeolotropism. Based on these analysis data, authors inferred the shale diagenetic evolution is at the diagenetic B period, the mineral bitumen mass and solid bitumen macerals organic matters are contributed to the shale gas mainly, and by calculating the plane porosity by MATLAB, the fractal dimension is about 2.57. Pores diameters of these samples range from 1-55nm, and the maximum is 4nm. Most pores are around medium pores. In summary, shale gas migrates obeying non-Darcy flow along pores/fracture several nanometers, and gas migration affected by organic matter mainly in Wufeng-Longmaxi formation in Southeast Sichuan basin, China.

Zonal flows in rotating systems have been previously shown to be suppressed by the imposition of a background magnetic field aligned with the direction of rotation. Understanding the physics behind the suppression may be important in systems found in astrophysical fluid dynamics, such as stellar interiors. However, the mechanism of suppression has not yet been explained. In the idealized setting of a magnetized beta plane, we provide a theoretical explanation that shows how magnetic fluctuations directly counteract the growth of weak zonal flows. Two distinct calculations yield consistent conclusions. The first, which is simpler and more physically transparent, extends the Kelvin-Orr shearing wave to include magnetic fields and shows that weak, long-wavelength shear flow organizes magnetic fluctuations to absorb energy from the mean flow. The second calculation, based on the quasilinear, statistical CE2 framework, is valid for arbitrary wavelength zonal flow and predicts a self-consistent growth rate of the zonal flow. We find that a background magnetic field suppresses zonal flow if the bare Alfvén frequency is comparable to or larger than the bare Rossby frequency. However, suppression can occur for even smaller magnetic field if the resistivity is sufficiently small enough to allow sizable magnetic fluctuations. Our calculations reproduce the η/B0^2 = const. scaling that describes the boundary of zonation, as found in previous work, and we explicitly link this scaling to the amplitude of magnetic fluctuations. These results could provide a plausible explanation for why the zonal jets in Jupiter go as deep as Juno has discovered but not any deeper.

The combination of strontium (87Sr/86Sr) and uranium (234U/238U) isotopes is an especially useful tool to track and quantify mixtures of water sources in arid wetlands, where chemistry and lighter isotopic tracers are strongly influenced by evaporation and transpiration. Those isotopes were used to understand modern water supply to the Pahranagat National Wildlife Refuge (PNWR) in southern Nevada (Paces & Wurster, 2014, J. Hydrol. 517). We investigate the possibility that this isotopic combination might also track paleohydrological changes in such settings. Here, we present Sr and U isotope data for authigenic carbonates in a sediment core spanning 5800 14C cal years from Lower Pahranagat Lake (LPAH), a shallow, alkaline lake within the PNWR. Modern surface waters in the PNWR are comprised of mixtures of discharge from two high volume springs from the regional carbonate aquifer in the northern valley, and smaller amounts of local discharge from the shallow volcanic aquifer in the southern valley. Modern surface water from LPAH has U isotopic values similar to the most recently formed LPAH carbonates; however, Sr isotopic values in LPAH surface water are somewhat lower than values in those same carbonates. Combined Sr and U isotope values in Holocene LPAH carbonates fall within the range defined by the three primary spring sources and reflect varying mixtures of those sources supplying LPAH from mid-Holocene to modern time. Values in the oldest samples (~5800 14C cal yr BP) have distinct 87Sr/86Sr and 234U/238U values that nearly match the local spring end member, suggesting that LPAH water at that time was dominated by proximal volcanic aquifer sources. By ~5300–5200 14C cal yr BP, LPAH water was comprised of a nearly equal mixture of the three spring sources, marking a dramatic shift in hydrologic conditions that allowed contributions of surface flow from distal carbonate springs to the north. Values in samples from ~1,000–3,000 14C cal yr BP indicate decreased contributions from distal carbonate springs during two drought intervals; however, by 730 14C cal yr BP, surface flow from carbonate springs had resumed. Our results indicate that combined Sr and U isotopes preserve evidence of past changes in water sources in arid wetlands useful for interpreting evolving hydrologic conditions.

Storm-time geomagnetic disturbances induce significant geoelectric fields within the Earth that can adversely affect the operation of electric power grids. The recently completed magnetotelluric survey supported by the NSF EarthScope program (2006-2018) has produced a large public archive of impedance tensors across much of the continental United States (US). In this work, the EarthScope tensors are convolved with long time series of geomagnetic field variation recorded at USGS observatories to obtain estimated time series of historical geoelectric fields. Integrating these geoelectric fields across power transmission lines results in time series of geomagnetically induced voltages on each power line. These voltages are analyzed statistically to construct hazard maps of the maximum voltages that could be realized in transmission lines across the US for an extreme, once in one hundred-year, geomagnetic storm. In combination with grounding resistance data and network topology, these voltage estimates can be utilized by power companies to estimate extreme geomagnetically-induced currents within their networks. These voltage estimates can provide information on which power lines and substations are most vulnerable to geomagnetic storms and can guide power companies in assessments of where to install additional protections within their grid.

Index Terms: 1622: Earth system modeling; 1630: Land/atmosphere interactions; 1800: Hydrology; 1836 Hydrological cycles and budgets; 1840 Hydrometeorology; 1855: Remote sensing; 1996 Web Services; 4305: Space weather; 6334: Regional Planning This work addresses a key objective of SERVIR-Mekong Project related to integrating geospatial information in government decision-making, planning, and communication for societal good. The SERVIR-Mekong is a partnership between the U.S. Agency for International Development (USAID) and the U.S. National Aeronautics and Space Agency (NASA) formed to help regional organizations in the Lower Mekong Region to use information provided by Earth observing satellites and geospatial technologies in managing climate risks. Our work integrated multiple satellite-based earth observation systems, in-situ station data and spatial data with the Soil & Water Assessment Tool (SWAT) hydrologic model employed in the Mekong River Basin region to develop a Lower Mekong River Basin region’s hydrological decision support system. Simulated hydrological fluxes of streamflow, soil moisture, and evapotranspiration at the Lower Mekong River Basin were presented utilizing our developed hydrological decision support system. Our work results have been presented via multiple Tethys platforms, Tethys is an easily customizable platform that hosts web applications, that facilitate accessing NASA satellite-based earth observation systems as well as the Lower Mekong River Basin region’s hydrological decision support system. Earth observations data has provided solutions to assist people in the Lower Mekong River Basin to overcome various obstacles experienced in enhancing hydrological decisions that are related to difficult access and incompleteness, inconsistency, scarcity, as well as poor spatial representation of in situ data products.

The lunar surface consists of a regolith layer, i.e., fragmental and unconsolidated rock material of highly varied character, which covers the underlying bedrock. Understanding the structure and composition of the lunar regolith and the underlying bedrock is very important to reveal geologic features of the Moon, explore natural resources humans can exploit, and obtain valuable information regarding the history of the solar system. Electromagnetic radiations from the surface of the Moon at microwave frequencies depends on the physical, chemical, and electrical properties of the regolith layer and the bedrock. Moreover, the electromagnetic penetration depth changes with frequency which allows wideband microwave radiometers operating below 50 GHz to conveniently profile these properties versus depth to characterize the lunar regolith and bedrock with wide spatial coverage. Combining current models of depth-dependent physical and chemical properties with simple electromagnetic forward radiation models, surface emissions over the Apollo sites were simulated and compared with Chinese Chang’E-1 and Chang’E-2 multi-frequency microwave radiometer measurements. Potential sources of the differences between the simulations and measurements have been identified as the temperature dependence of the electrical properties of the regolith, bedrock type, surface and bedrock roughness, as well as density fluctuations, scattering due to inhomogeneities, and coherent interference of electromagnetic fields within the regolith. However, many of these subjects have been studied thoroughly for the remote sensing of the cryosphere; thus leveraging this experience with the rapid developments in radiometer designs, wideband microwave radiometers promise valuable scientific returns in future lunar missions.

Over 33,000 flash flood events recorded by the NOAA National Weather Service (NWS) between 2006 and 2017, after polygon warnings replaced county-wide warnings, are analyzed in terms of NEXRAD (Next Generation Weather Radar) radar coverage in two ways. Events are binned in two large categories according to whether the starting point of an event falls inside or outside the range implied by the 6 kft AGL bottom-of-the-beam altitude, accounting for beam clutter and beam obstructions. Separately, events are classified according to the percentage surface area covered under the 6 kft beam height for each NWS Weather Forecast Office (WFO) or state. Emphasis is on unwarned events associated with fatalities, injuries and property damage and their relationship to WFO-area NEXRAD coverage. Significant property damage is defined in terms of the mean damage per event of about $411k. There is parity in the ratio of events warned or unwarned inside the inside/outside distance bins except for injury-event ratios. The linear fits to the traditional metrics of warned ratio (WR), false alarm ratio (FAR) and critical success index (CSI) are statistically significant and improve with more radar coverage. A stronger sensitivity is found for the WR as a function of the total number of events. New metrics are also evaluated, such as the mean flash flood partial event warning (PEW) and the ratios of unwarned to all events per WFO have statistically significant variations with radar coverage, improving with higher coverage. This is unlike the linear fits to the ratios of unwarned fatal-to-all-fatal events, which is marginally significant. Unwarned fatal-to-all-fatal, unwarned injury-to-all events and unwarned significant damage-to-nonzero damage event ratios are both not statistically significant to the 95% level of significance. The large scatter in the data results in very low coefficients of determination, and is interpreted to mean that radar coverage alone is not necessarily the primary driver though there is sensitivity to variations in such coverage.

Land use/land cover (LULC) change could adversely affect watershed health by elevating nutrients and sediment levels and intensifying the risk of flooding. In this study, a spatially-explicit LULC change modeling framework was coupled with the Chesapeake Bay Watershed Model (CBWM) to investigate the impact of LULC change on nutrients (total nitrogen and total phosphorous), sediment and runoff volume in the watersheds surrounding Virginia’s Shenandoah National Park, U.S. Four stakeholder-informed scenarios alongside a Recent Trends LULC change scenario were studied. The stakeholder-informed LULC change scenarios, which differed in consideration of future planning and population growth, were developed through several meetings with stakeholders. To develop the Recent Trends, the historical LULC trend from 2001 to 2011 was analyzed. Using 2011 as a baseline scenario, the spatio-temporal patterns of LULC change were estimated as influenced by physiographic and socio-economic drivers 50 years in the future (2061). The projected LULCs were fed into the CBWM to predict the change in average annual loading of nutrients, sediment and runoff volume. While the changes in loads at the full study area were not substantial (< 0.9%), changes became more pronounced at finer spatial scales. Expectedly, the LULC change scenario with ad-hoc planning and high population growth resulted in the largest increase in runoff volume. However, the scenario with ad-hoc planning and low population growth showed the largest increase in the simulated pollutants. This was because while this scenario projected less development, it projected more increases in agricultural LULCs that export more nutrients and sediment than other changing LULCs. This implied that sole land use planning based on urban development is not sufficient for watershed protection and agricultural LULCs need to be incorporated in concert in our future planning. This further suggested that land use planning plays a more critical role than population growth rate in water quality management. The results have implications for the Chesapeake Bay total maximum daily load and could help well-informed future land use planning and watershed protection by incorporating the impact of future LULC change on water quality and quantity.

Mangrove forests, occupying tropical and subtropical coastal areas, serve as coast protector, water filter, spot of attraction and an exceptional carbon reservoir. Despite these extraordinary ecological and economic functions, our understanding of the mangroves is limited because field survey is hard to conduct in the intertidal mangrove habitats. While satellite remote sensing provides good spatial and temporal coverages globally, data availability at the tropical latitudes is limited due to frequent cloud contamination. The quickly emerging unmanned aerial vehicle (UAV) technique enables data collection under almost all weather conditions, thus provides new opportunities. By mounting light detection and ranging (LiDAR) sensors on UAVs, the 3D structure of mangroves can be accurately characterized even at individual tree level. The basic tree parameters such as tree height and crown size can be easily extracted, which then enables the estimation of biomass, carbon stock and other important ecological indices. This study uses high density (>100 pt/m2) UAV-LiDAR data collected at four consecutive years to detect the growth rate and pattern of mangroves. The change detection is done at individual tree level. The dependence of mangrove growth pattern on tree species and clumpingness are analyzed. The output will allow scientists and environment managers to know mangroves better and to manage them effectively and efficiently.

Based on a large database of Wideband Imaging Camera (WIC), which is a part of Far Ultraviolet (FUV) instrument, onboard the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) satellite during 5 years between 2000 and 2005, we found a new morphological type of transpolar arcs (TPAs), which are identified as “nightside distorted TPAs”. The nightside ends of the dawnside (duskside) TPAs got distorted toward pre- (post-) midnight sector; These TPAs look like the shape of an alphabetical letter of “J” or “L”. We identified 17 nightside distorted TPAs from our database. The 12 events out of 17 nightside distorted TPA events were the dawnside TPA with the nightside end distorted toward the pre-midnight sector (“J”-shaped TPA), and the TPAs in the duskside, whose nightside parts got distorted toward the post-midnight sector, were found in the remnant 5 events (“L”-shaped TPA). Statistically, the nightside distorted TPAs can dominantly be found under the northward Interplanetary Magnetic Field (IMF) conditions. Furthermore, when the IMF-By component pointed to the dawnward (duskward) direction, the “J” (“L”)-shaped TPAs were dominantly observed, suggesting that the relation between the IMF-Bz and By orientations, and the locations of the nightside distorted TPAs is consistent with that between the IMF conditions and regular TPA previously reported. We also followed the time sequence of the nightside distorted TPA evolution with the IMAGE FUV-WIC imager and additional Polar UVI data. In most cases, the “J” and “L”-shaped TPAs started to grow from the nightside main auroral oval, and protruded to the dayside region with being distorted. In this presentation, we will introduce several selected cases of the nightside distorted TPA among our database, and discuss why and how the nightside end of the TPA became distorted toward pre- or post-midnight sectors based on the in-situ satellite nightside plasma sheet observations and the electron drift velocity distribution calculated utilizing a simple electromagnetic field model in magnetotail, together with the auroral imager data.

A hybrid Linear Programming (LP) and Nonlinear Programming (NLP) optimization model is developed for California’s hydropower operations. Built on top of Pyomo library, a high optimization modeling language in Python, the model can connect to several freely available, state-of-the-art solvers. In this model, fast evaluation of LP and detailed model representation of NLP are fully utilized. The hybrid model solves the same problem with linear approximation (a simplified objective function representation) and with NLP solver, where no simplification is made to objective function. Outputs from LP model are used as initial values (warmstart) for NLP model’s decision variables, which reduce number of iterations for convergence and so runtime. The model is capable of representing large network of hydropower plants that are in serial or parallel, or fixed and variable head plants. The model is used to evaluate effects of increased solar photovoltaic (PV) generation in California. California has a goal of generating electricity from renewable resources at least 33% by 2020, and 50% by 2030, and solar PV generation supplies most of renewable generation portfolio during daytime. This expanded use of solar PV changes generation pattern from one daily peak system to two daily peak system. Due to excess generation of solar PV, negative prices can occur during daytime. Therefore, evaluating effects of solar PV on hydropower operations and adapting to new conditions are essential.