The resonant charge exchange coupling between H+, H, O+ and O is a major driver of H+ and O+ transport between the plasmasphere and topside ionosphere. In this work, we present a new technique to derive model-independent neutral atomic hydrogen density, [H], based on parametric solution of the proton continuity equation including charge-exchange-driven transport. Estimation of [H] using the proton continuity equation incorporates atomic oxygen density [O] derived from the inversion of 135.6 nm OI emission measured by TIMED/GUVI and coincident ionospheric parameter measurements from the Arecibo incoherent scatter radar. Furthermore, by solving both the H+ and O+ continuity equations simultaneously, this work also quantifies the field-aligned vertical transport of protons between the plasmasphere and ionosphere and its effect on maintenance of the nightside and dayside ionospheric composition. Case studies during geomagnetically quiet intervals show that the transport of protons from the plasmasphere during nighttime is sufficient for the maintenance of the observed ionospheric O+ composition through reverse charge-exchange with O. Resulting O+ can diffuse upward or downward away from the source, which leads to observed counter-streaming of H+ and O+. Higher O+ densities on the dayside result in the charge-exchange production of H+, which acts as a source of protons to the plasmasphere. In summary, this work provides an unprecedented, model-independent quantification of diurnal conservation of plasmaspheric protons and its effect on ionospheric variability during quiet-times.

Carbon-capture and sequestration (CCS) in geologic reservoirs is one strategy for reducing anthropogenic CO2 emissions from large-scale point-source emitters. Recent developments have shown that basalt reservoirs are highly effective for permanent mineral trapping on the basis of CO2-water-rock interactions, which result in the formation of carbonate minerals. However, the injection of super-critical CO2 into the subsurface causes a disturbance in the pressure, temperature, and chemical systems within the target reservoir. How the ambient conditions change in response to a CO2 injection ultimately affects the transport and fate of the injected CO2. Understanding the behavior and transport of CO2 within a geologic reservoir is a difficult problem that is only exacerbated by heterogeneities within the reservoir, for example, permeability can be highly heterogeneous and exhibits significant control on the movement of CO2. The non-isothermal effects that accompany a CO2 injection are also affected by heterogeneous reservoir properties. These non-isothermal effects can lead to significant changes in temperature in both the reservoir water and rock, which can also affect the injectivity and movement of the CO2. This study is focused on gaining a better understanding of the non-isothermal effects of a CO2 injection and how the changes in temperature will affect the movement and reactivity of the CO2, as well as investigate the efficacy of using temperature as a proxy for CO2 breakthrough in the subsurface. iTOUGH2 eco2n is utilized to simulate CO2 injections into a 1D radially symmetric domain over a range of permeabilities, porosities, and salinities. Preliminary results indicate that for a modest CO2 injection rate of 31,500 metric tons/year the exothermic dissolution of CO2 can cause a temperature increase of up to 3.6oC at the edges of the CO2 plume and the Joule-Thomson effect can cause a decrease in temperature up to 10oC near the injection well. Additionally, results from this study indicate that the thermal effects of a CO2 injection, namely the heat of dissolution associated with a large-scale CO2 injection may be an effective MMV strategy for monitoring CO2 breakthrough.

In this study, we present and validate a new numerical solver in OpenFOAM®-v1706 called “ibmPorFoam” that is developed modifying IHFOAM (Higuera et al., 2014) with Immersed Boundary Method. IHFOAM is previously developed modifying interFoam solver of OpenFOAM® to solve flow properties in porous media. IHFOAM solves Volume Averaged Reynolds Averaged Navier-Stokes Equations, captures the free surface using Volume of Fluid method, and is capable of generating and absorbing waves. Immersed boundary method implemented in this study is based on body force approach given by Liu (2013). ibmPorFoam is validated in two parts by using k-ε model as the turbulence closure. In the first part, a porous dam-break experiment (Lin, 1998) is studied as a 2D case study. Free surface measurements inside and outside the porous medium are compared with the numerical results. In the second part, 3D numerical simulations are carried out to determine flow properties around a rigid, impervious box based on the experimental setup of Kleefsman et al. (2005). Numerical results are compared with the experimental results at wave gauges along the channel and pressure gauges located on the box. Both experimental cases are also simulated using IHFOAM to observe the differences in the numerical solvers. It is seen that the results of numerical simulations conducted with ibmPorFoam are in fairly well-agreement with both experimental results and numerical results from IHFOAM. Acknowledgement: Support from TUBITAK, Turkey (Project No: 217M722) is acknowledged. References Higuera, Lara, Losada (2014a), 3D Interaction of Waves and Porous Coastal Structures using OpenFOAM®, Coastal Eng., 83, 43-258. Kleefsman, Fekken, Veldman (2005), A Volume-of-Fluid Based Simulation for Wave Impact Problems, J. Comp. Physics, 206, 363-393. Lin (1998), Numerical Modeling of Breaking Waves, PhD Thesis, Cornell University. Liu, X. (2013), Realistic Flow Simulations around and inside Porous Scour Protection, in proceedings of 2013 IAHR Congress, 1–8.

The western region of Bay of Bengal (BoB) is of high importance because of its variability in Western Boundary Current (WBC) pattern, numerous eddy genesis and biogeochemical activities. The WBC is northward in pre–Indian Summer Monsoon (ISM) season and southward in post–ISM season with the presence of anticyclonic and cyclonic gyres respectively. During ISM, the western BoB is dominated by various cyclonic and anticyclonic eddies with discontinuous WBC. The seasonally reversing wind pattern also favors the variation in the circulation pattern of the bay. The mechanism of eddy genesis in the western BoB and their characteristics specially during ISM, when the WBC is discontinuous, is not studied well. Our study uses the Regional Ocean Modeling System (ROMS) to investigate the role of coastal Kelvin wave, which originated from the equatorial wave guide, and local wind on the mesoscale eddies in the western BoB. To better understand the forcing mechanism involved, river influx and modified wind fields are incorporated in the experiments. The simulated Kelvin wave propagation is consistent with the satellite altimetry observations. Two upwelling and two downwelling Coastal Kelvin Wave (CKW) signals are identified. First upwelling signal (UCKW1) exists from January to April whereas the second signal (UCKW2) appears in September. Two downwelling signals are seen from May to August (DCKW1) and October to December (DCKW2), respectively. Depth of 20°C isotherm (D20) shows good correlation with the remote forcing signals as well as surface wind variability. The CKW signals during pre– and post–ISM (UCKW1 and DCKW2 respectively) are dominant. The reversing weaker signals (DCKW1 and UCKW2) contribute to the WBC discontinuity during ISM. Reduction in wind fields results in weak WBC during pre– and post–ISM. Increase in wind field results in strengthening of the weaker CKW modes rather than strengthening the WBC. Average surface eddy kinetic energy along with eddy intensity, radius and lifetime are sensitive to the change in wind field. The eddies are seen to propagate clockwise (anticlockwise) in general due to decrease (increase) in wind field. The study indicates that the CKWs and the local wind have significant impact on seasonally reversing WBC, eddy genesis and their characteristics in the western BoB.

ERDDAP is a data server developed at NOAA Southwest Fisheries Science Center that allows users to easily access and download subsets of gridded and tabular data. At the Scientific Data Integration Group at NOAA’s Pacific Marine Environmental Laboratory we have focused on ERDDAP as the primary mechanism by which we serve all of our tabular data. Besides offering data access in a variety of useful formats, ERDDAP takes care of normalizing the data structure so that all tabular data sets have a simple row and column structure. Additionally, time values are normalized to have a consistent units across all data sets on the server. The simplified tabular nature of the discrete data in ERDDAP lends itself nicely to use with the Google Visualization API (Google Charts). Charts is an API which renders nearly all of the graphics in the browser client. The basis of all charts is the Google Charts DataTable which is exactly analogous to a TableDap table in ERDDAP. Charts are interactive, visually pleasing, free and easy to use and so connecting ERDDAP data to Google Charts is a natural fit. Even though ERDDAP has many output formats including several different JSON renderings, none fit exactly into the specified Charts data types. Initially, as a result, it was necessary to create custom code (either in the client or on a server between the client and the ERDDAP server) to manipulate the ERDDAP data stream to match the Charts API requirements. However, since Charts has a well-documented specification for a JSON representation of the required data type and because ERDDAP is an open source project, it was possible to extend ERDDAP to support the Charts DataTable as a new data type. Using this new data type, it’s possible to instantiate a Charts DataTable object directly from the ERDDAP URL using a simple Ajax call in the client which downloads the JSON DataTable representation. Because the newly added data type is now native to ERDDAP, it is possible to use default constraint syntax and ERDDAP RESTful services (using the ERDDAP user interface if desired) to build the URL for the exact data subset which is to be visualized by the desired google chart. In this presentation, we’ll explain what we’ve done to add the JSON data type to ERDDAP and provide many examples of client-side rendering of earth science and engineering data using Google Charts directly from ERDDAP URLs.

Coral reefs are one of the most diverse ecosystems on Earth and provide significant ecological, economic, and societal benefits valued at approximately $9.8 trillion U.S. dollars per year. While there are multiple ways humans threaten coral reefs, climate change has become the single most important of these threats. NOAA’s Coral Reef Watch is the only program that operationally issues coral bleaching forecasts, using near real-time satellite monitoring to provide ecological nowcasting of the ocean heat stress that can cause mass coral bleaching and using climate models to forecast the potential for bleaching months into the future. Ocean temperatures began to rise in mid-2014, starting what turned out to be three full years of marine heatwaves that caused corals to bleach — expelling their symbiotic algae. When the film team at Exposure Labs started exploring how to film coral bleaching as it happened, Coral Reef Watch was an obvious partner. Exposure Labs worked with numerous scientists, including me as a Co-Chief Scientific Advisor, to get the science behind the Sundance-Award Winning film Chasing Coral correct. The film team went to great extremes to ensure every statistic, graph, scientific principle, and animation was clear and accurate – using science to explain and support the adventure of trying to capture the first on-reef time-lapse imagery of this important phenomenon. The result is a visually compelling film that tells the story of climate change and its impacts on an important ecosystem in a way that appeals to audiences, including viewers who usually would not sit down to watch a climate change documentary. Chasing Coralis an extremely effective combination of science and art that opens opportunities for dialogue on climate change in ways no scientific paper ever could.

Large life, as currently present on Earth, diversified during a late and seemingly non-trivial historic event. Although other biological revolutions – such as the advent of photosynthesis or the eukaryotic cell – are attributed to innovations within life itself, the dramatic diversification of animals tends to associated with a change in the environment. The environmental change that remains most thoroughly explored and debated is that of a synchronous increase of free oxygen. Paradoxically, studies of multicellularity from the perspective of tissue and of successful tumor growth highlight how oxic settings are incompatible with the core mechanism of tissue renewal (Ivanovic, 2009). Tumor biology also demonstrates biological mechanisms that, through the hypoxia inducible transcription factors (HIFs), overcome this paradox (Pietras et al., 2008) and, thus, allow tissue renewal despite oxic settings. We have explored how HIFs may serve as an adaption within multicellularity that allow viable large life forms in the oxic setting, by offering improved control of the cellular hypoxia-response machinery that sustain oxygen-insensitive growth of complex tissue. We found that this control is animal-specific and is at its highest refinement within vertebrate animals; in which the innovation of high-oxygen carrying capacity through red blood cells followed first subsequently (Hammarlund et al., 2018). We hypothesize that such a refinement within biology itself, during the Neoproterozoic, allowed metazoans to fully access and exploit the primordial oxic niche on Earth. Testable predictions of this perspective, such as that invertebrate animals and other large multicellular organisms still require phases or settings of truly hypoxic conditions to manage tissue renewal, have implications that reach from geology and medicine to astrobiology. Indeed, a perspective based in the prerequisites of tissue maintenance suggests that being large is a biological achievement of cosmic proportions.

The NASA InSight mission, landing in late November 2018, promises to revolutionize our understanding of Martian interior structure via analysis of seismic data returned by the SEIS instrument. The extent to which the mission’s potential is realized will depend on the number of detectable seismic events that occur during the period of operation. Here I estimate the rate of detectable events generated by volcano-tectonic activity on Mars based on extrapolation of Hawai’i’s seismic record. I use a catalog of 5603 earthquakes spanning 48 years [IRIS, 2018], with moment magnitudes MW ranging from 3.0 to 6.9, to derive the Gutenberg-Richter (G-R) frequency-magnitude relation for the Island of Hawai’i, expressed as log(N) = a – b MW, where N is the number of earthquakes with magnitudes greater than or equal to MW, and a and b are constants. By this analysis, one earthquake with MW 5.1 or greater can be expected every year at Hawai’i. Under the assumption that the mechanisms of seismicity associated with edifice building are similar at Hawai’i and Olympus Mons (supported by observation of decollement-based volcanic spreading at both), I use the same b for both settings and scale a according to estimates of magmatic volume flux rates dV/dt at both settings. Over the 80 Myr history of the Hawaiian-Emperor volcanic chain, dV/dt ≈ 1.7 x 10-2 km3/yr. An estimate of dV/dt for the Olympus Mons volcano on Mars was derived from paleotopographic analysis of a set of lava flows south of Olympus Mons with discordant topography. Given the mean flow age from crater counts (210 Ma), an estimate of the amount of volcanic material needed to cause deflections of flow orientations of the required magnitudes yields estimates of dV/dt over this timespan ranging from 6.33 x 10-4 to 6.43 x 10-3 km3/s. Taking the mean of these values and scaling a by the ratio of dV/dt values for Mars and Hawai’i yields a rate of at least 1 quake of MW = 4.4 or greater per year (Figure 1). Thus, under several assumptions (including a steady recent magma supply rate for Olympus Mons), we can expect ≈ 2 volcano-tectonically driven quakes of magnitude MW > 4.4 from the vicinity of Olympus Mons during the nominal 2 Earth-year InSight prime mission. This is a conservative lower bound that does not consider contributions from numerous potential volcano-tectonic sources in Tharsis and elsewhere on Mars.

Glaciers act as hydrologic reservoirs in mountain environments around the world. In regions that are particularly water-stressed, such as the Andes, glaciers contribute significantly to water resources in downstream communities. As these glaciers recede rapidly throughout the Andes under climatic changes, the surface composition of their ablation zones appears to be shifting from predominantly clean-ice to debris-covered ice. Determining what climatological and topographical factors control debris-coverage in the ablation zones of glaciers throughout the Andes will assist in understanding why these glaciers are becoming increasingly covered by debris and how this debris coverage will continue in the future. By exploring multiple drainage basins across the Andes, this study will discover which regions are most impacted by this transition. Debris-coverage is known to have varying impacts on the ablation rates of glaciers and likely alters the sub-glacial and pro-glacial hydrology of the drainage basin they reside in. With debris-covered glaciers becoming more prevalent across the Andes, it is imperative to gain a better understanding of the hydrology of these complex cryospheric features. Through the use of terrestrial photogrammetry and hydrological techniques, this study will investigate the controls of debris coverage and assess the hydrological impacts of this debris on glaciers throughout the Andes.

Droughts are a recurrent phenomenon in water abundant tropical countries worldwide and are expected to become more frequent in the future. However, drought risk in tropical catchments is poorly understood and usually not adequately incorporated in water management strategies. Thus, methodologies to evaluate spatial and seasonal drought risk in data scarce tropical catchments are urgently needed. We combined hazard and vulnerability related information to assess drought risk in the test basin, the rural Muriaé basin in southeast tropical Brazil. Hazard indicates the cumulative frequency of drought anomalies, while vulnerability represents the potential of a drought to cause damages in the socioeconomic system. We simulated subcatchment discharges with a hydrological model (SWAT) to evaluate spatially distributed hydrological drought hazard and combined this information with precipitation and vegetation based indices to define the cumulative frequency of drought occurrence for each grid cell (0.1°). We tested the sensitivity of different climate and catchment related model input variables against low flow events and simulated artificial drought risk scenarios. To assess vulnerability, we reclassified and weighted globally and regionally available gridded socioeconomic data. Vulnerability in the downstream area was found to be stronger which coincided with a higher hydrological and vegetation based hazard. The drought risk map clearly identified the downstream area of the Muriaé basin as being exposed to a stronger drought risk compared to the upstream areas. Only limited hydrological drought sensitivity of the system against changes in land cover type and temperature was shown in the model results while geology and soils turned out to play a larger role for low flows. The drought scenarios showed that low flows were more severely affected than high flows by climatic changes such as decreased precipitation. In can be concluded that our risk assessment methodology offers a holistic, science based and innovative solution to inform regional planning and water management institutions dealing with the control of drought disasters in tropical rural areas. Such drought risk evaluation frameworks and spatial information are urgently needed in tropical regions worldwide.

Water-Energy-Food Nexus assessments at river basin scale make sense in particular if hydropower is an important source of energy in a given region. The Blue Nile Basin is a major source for Water in the Nile river basin. It provides around 65 % of the flow of the Nile entering Egypt, and occupies a mere 10% of the total basin area. The Blue Nile water is primarily used for irrigation, hydropower, and domestic supply in Ethiopia, Sudan, and Egypt. Climate variability and long-term climate and socio-economic changes pose a growing challenge to the provision of water, energy, and food security within the Blue Nile Basin as well as downstream. Thus, the scientifically sound quantification of available natural resources sustaining water, energy, and food security, and the development of different future scenarios can be helpful for decision-makers in the region. We suggest a new method of WEF Nexus accounting based on quantification of Nexus indicators derived mainly from public domain data. As observed data on water and land resources in the Blue Nile Basin are scarce, this study uses diverse remote sensing-based data sources to derive essential environmental information validated by using ground data, where possible. This includes land cover data, different precipitation products, actual evapotranspiration, net primary productivity (NPP), among others. Furthermore, several data analysis and modeling tools, such as WA+, various hydrological models, RiverWare, CropWat, etc., are employed to quantify the natural resources availability, variability, and productivity as a basis for a comprehensive WEF accounting based on selected indicators which were developed by a team of experts and scientists. The currently constructed Grand Ethiopian Renaissance Dam (GERD) as well as other planned hydropower and irrigation schemes are also considered for the future scenarios. The result is a comprehensive WEF Nexus accounting estimating water availability and uses with a focus on irrigation as the dominant water user, productivities (based on NPP and derived yield estimates), water use efficiency, energy production from hydropower and estimation of security levels compared to the required current and future demands. Finally, the derived nexus indicators are put into context of selected SDG target indicators.

Low seasonal precipitation and high demand for water use for agriculture, mining, industry, power generation and human consumption have made water resources management a concern in the Arequipa Region of Peru, which may be worse under future climate projections. In this study, the hydrologic response to climate change is evaluated within the Quilca-Vitor-Chili River Basin in the Arequipa Region of Peru. The Soil and Water Assessment Tool (SWAT) is used to develop a watershed model based on topographical, land cover, soil, and climatic (precipitation and temperature) data, while taking into account anthropogenic inter-basin transfers. The model is calibrated and validated for current conditions. Three climate scenarios derived from Atmosphere-Ocean General Circulation Model (AOGCM) simulations for both Representative Concentration Pathways (RCPs) 4.5 and 8.5 are obtained from the NASA Earth Exchange Global Daily Downscaled Projections (NEX-GDDP) dataset. Surface runoff and water yield associated with future climate scenarios are calculated for two near (2010-2039) and far (2040-2069) futures. Results of this study will provide a guideline for developing water policy in the region in order to mitigate negative impacts of climate variations in the region.

Federal agencies in the US must evaluate the environmental justice implications of regulatory actions. Environmental justice analyses frequently use demographic tests to determine whether regulated projects will disproportionately impact vulnerable communities, including American Indian communities. Demographic tests typically yield negative results, which are often cited as evidence of no environmental justice implications. However, susceptibility of demographic tests to false negative errors is unknown. In these cases, false negative errors occur when a test cannot identify a vulnerable population concentrated disproportionately within a project study area. We developed a technique to evaluate the susceptibility of demographic tests to false negative errors. We used the technique to assess a test commonly used by regulators to permit fossil fuel pipelines. The Atlantic Coast Pipeline served as a case study. The demographic test did not identify disproportionately large American Indian populations under any realistic scenario, a false negative error rate of 100%. In our case study, the test did not detect a disproportionately large American Indian population until the study area contained a four times greater fraction of American Indians than the reference area. We extend the results to study the test’s performance throughout the US. The test’s inability to detect disproportionately large American Indian populations calls into question the validity of negative results and the general ability of the test to inform conclusions about environmental justice or sustainability. We recommend abandoning the test in favor of more rigorous methods.

Deep convective storms assume many intensities, sizes and morphologies in Earth’s atmosphere, reflecting varying balances of the competing forces that arise in the diverse atmospheric conditions that promote and support such storms. The understanding of how these forces compete with each other lends itself only with great difficulty to observational study, but much more easily to idealized parameter space studies using numerical models. A parameter space study was recently designed and executed using an eight-dimensional framework, with 2-h experiments run using all possible combinations of reasonably chosen high and low values of the eight independent parameters. The basic parameters are those needed to build an idealized vertical profile of temperature, moisture and wind: bulk convective available potential energy (CAPE), radius of an assumed semicircular hodograph, shape of the buoyancy profile, shape of the shear profile, lifting condensation level, level of free convection, cloud-base temperature (roughly equivalent to total precipitable water), and free tropospheric relative humidity. Each of the parameters is found to exert noteworthy independent impacts on the intensity and morphology of the convection, with drastic differences in updraft overturning efficiency (the ratio of simulated peak updraft speed to that predicted from pseudoadiabatic parcel theory), updraft rotation, updraft steadiness and precipitation efficiency. Storm rotational efficiency relative to ambient vertical shear, and its steadiness, may also be examined. Results will be shown that demonstrate the strongly patterned convective response within this large parameter space, for both updraft overturning and rotational efficiency and their temporal steadiness. For example, in experiments having CAPE = 2000 J/kg, peak updraft efficiency reaches 94% in some cases, while in others with unfavorable combinations of parameters, that peak is less than 20%. While the eight basic parameters used in this study cover most of the variability of the vertical meteorological structure of the convective atmosphere, the framework can easily be expanded by adding new dimensions to deal with other physical effects, such as varying types and distributions of aerosols and other tracers that influence atmospheric chemistry.

Earthen dam failures of high hazard dams are expected to cause downstream human life loss and economic and environment loss. Of the three most prevalent failure modes for earthen dams, seepage (or piping) failures account for approximately 40 percent. All earthen dams seep and it is not uncommon to observe some seepage on the downstream toe, but the flow rate of uncontrolled seepage should be negligible. In general, seepage occurs through the dam and/or its foundation. The cross section of the dam is designed to force the waterside head (pressure) to drop as the water flows through the cross section to the downstream toe. Uncontrolled or unexpected seepage can promote soil movement (i.e. piping) and cause a pipe or a cavity to develop within the earthen structure which can lead to a complete failure of the embankment. At present there are over 84,000 earthen dams throughout the United States many of which depend on the US Army Corps of Engineers for inspection, monitoring, maintenance, and repair. Recently a multi-method geophysical investigation, was performed at a site where a suspected seep outflow had increased ten-fold, warranting further investigation. Because the seep presented in a historically dry stream channel in the karst bedrock adjacent to the dam abutment there was some question as to whether the origin of the seep was indeed a result of piping or due to a naturally occurring seasonal spring. Electromagnetic induction measurements of terrain conductivity, as well as electrical resistivity tomography and mise-a-la-masse surveys were performed in an attempt to delineate the source water of the seep. The geophysical methods identified potential flow paths from the impoundment to the seep; however, a geochemical analysis of the seep outflow was compared to the same analysis of the impoundment water on the upstream side of the dam and found to be statistically different.

In the semi-arid Andes Cordillera of central Chile (31–36°S), mountain glaciers are important reservoirs of freshwater, especially during droughts, contributing between 70 and 80% of the total runoff. In this work, we use the physically-oriented and spatially-distributed TOPKAPI-ETH glacio-hydrological model to simulate the response of glaciers to severe droughts in the Olivares River catchment. The glacierized area of this catchment is equivalent to 26% of the total glacier area in the Maipo River basin, the main source of surface water for Santiago de Chile – where more than 40% of the population in the country lives. To this end, we force TOPKAPI-ETH with synthetic droughts under several scenarios of glacier retreat, defined by two climate scenarios: i) current climate, preserving the mean and standard deviation of precipitation and temperature observed during the period 1990-2009, and ii) considering the Paris Agreement and constraining the global temperature rise – relative to preindustrial levels – to 1.5°C, projected by a small number of climate models under the RCP2.6 long-term scenario. We also use outputs from regional climate model simulations generated by the Center for Climate and Resilience Research (CR2) to represent what would be an increase of mean temperature in our domain. To assess the hydrological response of glaciers, and the contribution to total runoff under these scenarios, we compare our results with those obtained for droughts observed in this region during 1967-1969 and 2010-2015, considered as the most important events to date in Chile. Ongoing efforts are oriented to quantify ice loss under current climatic conditions, elevation line altitude variations during the long-term simulation, variations in glacier area and volume, and basin response to future drought under glacier retreat scenarios. Preliminary results show that glacier relative contribution to runoff at the end of the summer season increases up to 25% during the reference droughts, but decreases about 40% to 75% in comparison to the reference period considering climate scenarios.

Sap flux probes have been used to study sap velocity since the early 20th century and have progressively improved in accuracy and usability. Advances are also being made in making these devices cheaper via open-sourced projects; however, these solutions require extensive time and skill to construct a reliable device. When our lab tried to replicate Miner’s results, only two of the first ten probes built passed rudimentary testing. We therefore redesigned the system in a PCB-based design that simplifies construction, and presents opportunity for automated mass manufacturability at a scale not possible with existing designs. New designs for both the Thermal Dissipation Method (TDM) and the Heat Ratio Method (HRM) techniques were tested. We present our open-source designs for wireless sap flux probes that communicate over 2km using the LoRa protocol through canopy to an internet hub, where data is logged in near-real-time and accessible online.

Many resource management studies focus on one resource. Humans, however, rely on multiple resources in a complicated way. A person may derive more well-being from one unit of a resource than from another; one resource may be substituted by another to some degree. How should one manage such coupled natural-human systems? In this work, we build on recent research that focuses on developing conceptual frameworks and mathematical models to understand such interactions. The multiple resource condition injects the concept of substitutability into models of coupled human-natural systems and affects how such systems should be governed. Substitutability has been mostly mentioned in the field of economics for a substitution of natural and human capitals. Similarly, one resource may substitute for other scarce resources in coupled human-natural systems since some of these resources are not completely independent. In this study, we revise and expand an existing conceptual framework to include two natural resources, resource users, governing agency and public infrastructure in a centralized governance structure, i.e., all the natural resources are managed by the same governing entity. We then devise a set of dynamical equations and relationships from different fields, such as a replicator equation, a population equation, and a CES production equation, to capture the dynamics of this coupled system. This analysis can provide a decision-support tool to design policies to sustainably govern the built environment where human, natural resources, and infrastructure are interconnected. Model analysis takes a multi-faceted perspective of both resource users and governing entities to assess policies against different levels of disturbance. The results reveal how substitutability and asymmetry in resource use affect the viable policies needed to maintain the system.