Quantifying the Influence of Near-Surface Water-Energy Budgets on Soil Thermal Properties Using a Network of Coupled Meteorological and Vadose-Zone Instrument Arrays in Indiana, USA

Poster presented at American Geophysical Union Meeting, 2012.Weather stations that collect reliable, sustained meteorological data sets are becoming more widely distributed because of advances in both instrumentation and data server technology. However, sites collecting soil moisture and soil temperature data remain sparse with even fewer locations where complete meteorological data are collected in conjunction with soil data. Thanks to the advent of sensors that collect continuous in-situ thermal properties data for soils, we have gone a step further and incorporated thermal properties measurements as part of hydrologic instrument arrays in central and northern Indiana. The coupled approach provides insights into the variability of soil thermal conductivity and diffusivity attributable to geologic and climatological controls for various hydrogeologic settings. These data are collected to facilitate the optimization of ground-source heat pumps (GSHPs) in the glaciated Midwest by establishing publicly available data that can be used to parameterize system design models. A network of six monitoring sites was developed in Indiana. Sensors that determine thermal conductivity and diffusivity using radial differential temperature measurements around a heating wire were installed at 1.2 meters below ground surface— a typical depth for horizontal GSHP systems. Each site also includes standard meteorological sensors for calculating reference evapotranspiration following the methods by the Food and Agriculture Organization (FAO) of the United Nations. Vadose zone instrumentation includes time domain reflectometry soil-moisture and temperature sensors installed at 0.3-meter depth intervals down to a 1.8-meter depth, in addition to matric potential sensors at 0.15, 0.3, 0.6, and 1.2 meters. Cores collected at 0.3-meter intervals were analyzed in a laboratory for grain size distribution, bulk density, thermal conductivity, and thermal diffusivity. Our work includes developing methods for calibrating thermal properties sensors based on known standards and comparing measurements from transient line heat source devices. Transform equations have been developed to correct in-situ measurements of thermal conductivity and comparing these results with soil moisture data indicates that thermal conductivity can increase by as much as 25 percent during wetting front propagation. Thermal dryout curves have also been modeled based on laboratory conductivity data collected from core samples to verify field measurements, and alternatively, temperature profile data are used to calibrate near-surface temperature gradient models. We compare data collected across various spatial scales to assess the potential for upscaling near-surface thermal regimes based on available soils data. A long-term goal of the monitoring effort is to establish continuous data sets that determine the effect of climate variability on soil thermal properties such that expected ranges in thermal conductivity can be used to determine optimal ground-coupling loop lengths for GSHP systems

An Integrated Architectural Element Approach to Three-Dimensional Geologic Mapping of the Huntertown Aquifer System In Northeastern Indiana

This poster was presented at the 2008 Joint Meeting of The Geological Society of America, Soil Science Society of America, American Society of Agronomy, Crop Science Society of America, Gulf Coast Association of Geological Societies with the Gulf Coast Section of SEPM, October 5-9, Houston, TX.A three-dimensional geologic model of the Huntertown glacial aquifer system is being developed. Permeable hydrostratigraphic units within the Huntertown Formation (Quaternary) comprise the principal ground-water resource for an expanding population in northern Allen County, Indiana. The Huntertown aquifer system lies predominantly between the less permeable Lagro and Trafalgar Formations. The Huntertown Formation and corresponding aquifer system are located in an interlobate setting characterized by complex glacial stratigraphy, consisting of coarse-grained proglacial sediments and loamy till intercalated with glaciofluvial and glaciolacustrine facies. To construct the model, a database of more than 2,500 lithologic logs from public and private water supply wells and more than 200 down-hole natural gamma-ray logs was compiled for the study area (~500 km2). The lithologic logs were plotted to construct 110 hand-drawn cross sections (total length of about 900 km) that were used to map the bounding surfaces of the three formations (high-order architectural elements) as well as to constrain the scale and geometry of intratill sand and gravel aquifer units. The base of the Lagro Formation was determined from well logs by a shift from massive clays to loam-textured sediments or by the presence of laterally and vertically extensive underlying sand and gravel units. A prominent shift toward higher counts in natural gamma-ray profiles was also used to determine the base of the Lagro. The top of the Trafalgar Formation was defined by a ubiquitously present overlying outwash package depicted in gamma-ray logs or by lithologic descriptions reflecting the Trafalgar's overconsolidated nature. Previously mapped areal extents of hydrogeologic facies are currently being used in conjunction with both lithologic and natural gamma-ray cross sections, rendered at various orientations across the study area, to determine the geometry of individual morphosequences or lower-order architectural elements (e.g., ice marginal fans and outwash channels)

Monitoring near-surface thermal properties in conjunction with energy and moisture budgets to facilitate the optimization of ground-source heat pumps in the glaciated Midwest

This poster was presented at the American Geophysical Union Fall Meeting 2011, San Francisco, Calif., on December 7, 2011. It was part of IN33C, Geothermal energy research and discovery II posters session.By exploiting the near-surface heat reservoir, ground-source heat pumps (GSHP) represent an important renewable energy technology that can be further developed by establishing data sets related to shallow (<100m) thermal regimes. Although computer programs are available for GSHP installers to calculate optimal lengths and configurations of ground-coupling geothermal systems, uncertainties exist for input parameters that must first be determined for these models. Input parameters include earth temperatures and thermal properties of unconsolidated materials. Furthermore, thermal conductivity of sediments varies significantly depending on texture and moisture content, highlighting the need to characterize various unconsolidated materials under varying soil moisture regimes. Regolith texture data can be, and often are, collected for particular installations, and are then used to estimate thermal properties for system design. However, soil moisture and temperature gradients within the vadose zone are rarely considered because of the difficulty associated with collecting a sufficient amount of data to determine predominant moisture and temperature ranges. Six monitoring locations were chosen in Indiana to represent unique hydrogeologic settings and near-surface glacial sediments. The monitoring approach includes excavating trenches to a depth of 2 meters (a typical depth for horizontal GSHP installations) and collecting sediment samples at 0.3-meter intervals to determine thermal conductivity, thermal diffusivity, and heat capacity in the laboratory using the transient line heat source method. Temperature sensors are installed at 0.3-meter intervals to continuously measure thermal gradients. Water-content reflectometers are installed at 0.3, 1, and 2 meters to determine continuous volumetric soil moisture. In-situ thermal conductivity and thermal diffusivity are measured at 1.5 meters using a differential temperature sensor that measures radial differential temperature around a heating wire. Micrometeorological data (precipitation, insolation, ambient air temperature, relative humidity, and wind speed) are also collected to determine surface energy and water budgets that drive fluxes of energy and moisture in the shallow subsurface. By establishing continuous, year-round data, fluctuations in seasonal energy budgets and unsaturated zone soil moisture can be considered such that GSHP system designers can establish accurate end members for thermal properties, thereby optimizing the ground-coupling component of GSHPs. These data will also provide empirical controls such that soil moisture and temperature regimes can be spatially distributed based on mapped soil units and hydrogeologic settings in Indiana

Indiana Shallow Geothermal Monitoring Network: A Test Bed for Optimizing Ground-Source Heat Pumps in the Glaciated Midwest

This poster was presented at the 46th Annual Meeting of the North-Central Section of the Geological Society of America, April 23-24, 2012.Ground-source heat pumps (GSHP) represent an important technology that can be further developed by collecting data sets related to shallow thermal regimes. Computer programs that calculate the required lengths and configurations of GSHP systems use specific input parameters related to the soil properties to enhance the accuracy of models and produce efficient system designs. The thermal conductivity of sediments varies significantly depending on texture, bulk density, and moisture content, and it is therefore necessary to characterize various unconsolidated materials under a wide range of moisture conditions. Regolith texture data are collected during some installations to estimate thermal properties, but soil moisture and temperature gradients within the vadose zone are rarely considered due to the difficulty of collecting sufficient amounts of data. Six monitoring locations were chosen in Indiana to represent unique hydrogeological settings and glacial sediments. Trenches were excavated to a depth of 2 meters (a typical depth for horizontal GSHP installations) and sediment samples were collected at 0.3-meter intervals for a laboratory analysis of thermal conductivity, thermal diffusivity, bulk density, and moisture content. Temperature sensors and water-content reflectometers were installed in 0.3-meter increments to monitor changes in temperature and soil moisture with depth. In-situ thermal conductivity and thermal diffusivity were measured at 1.5-meters using a sensor that detects radial differential temperature around a heating wire. Micrometeorological data were also collected to determine the surface conditions and water budgets that drive fluxes of energy and moisture in the shallow subsurface. Preliminary results indicate that increases in water content can increase thermal conductivity by as much as 30% during wetting front propagation. Although there is a change in temperature associated with the infiltration of wetting fronts, thermal conductivity appears to be independent of soil temperature. By establishing continuous data sets, fluctuations in seasonal energy budgets and unsaturated zone soil moisture can be determined. This information can then be used to establish accurate end members for thermal properties and improve the efficiency of geothermal systems

Integrating Groundwater Observations with Models of Soil-Water Dynamics to Examine Recharge Patterns through Glacial Sediments in a Humid Continental Climate

Poster presented at American Geophysical Union meeting in 2015.Understanding the timing and magnitude of shallow groundwater recharge is critical for determining water balance and analyzing aquifer sensitivity for water resource planning. We analyzed data from six hydrometeorological monitoring stations using HYDRUS 1D to achieve physically based estimates of water-table recharge in various glaciated terrains in Indiana (USA). The models simulated runoff, root-water uptake, and flow through heterogeneous soil profiles to quantify water flux at the water table. Calibration by inverse modeling of data collected in 2013 yielded optimized hydraulic parameters that allowed accurate simulation of observed soil moisture (RMSE generally within 3%). The model validation period confirmed accurate simulation of soil moisture as well as correspondence between modeled recharge and observed water-table fluctuations. Additional modelling over a three-year study period indicated that diffuse water-table recharge in the region can be reasonably approximated as 35% of precipitation, but interannual and monthly variability can be significant depending on the glacial setting and pedological development. Soil parent material and horizon characteristics have a strong influence on average annual recharge primarily through their control on Ks, with clay-rich till parent materials producing values as low as 16% and coarse-grained outwash parent materials producing values as high as 58% of precipitation. The combined modelling and monitoring data reveal distinct seasonality of recharge, with most recharge occurring in the winter (seasonal mean of all sites was 66% of precipitation) and lesser but interannually stable amounts in the spring (44%), summer (13%), and autumn (16%). This ongoing research underscores the value of combining vadose zone characterization with hydrometeorological monitoring to more effectively represent how surface energy and moisture budgets influence the dynamics of surface water-groundwater interactions

Near-Common Zeros in Blind Identification of Simo Acoustic Systems

The common zeros problem for Blind System Identification (BSI) has been well known to degrade the performance of clas-sic BSI algorithms and therefore limits performance of subsequent speech dereverberation. Recently, we have shown that multichannel systems cannot be well identified if near-common zeros are present. In this work, we further study the near-common zeros problem us-ing channel diversity measure. We then investigate the use of forced spectral diversity (FSD) based on a combination of spectral shap-ing filters and effective channel undermodelling. Simulation results show the effectiveness of the proposed approach. Index Terms — blind system identification, near-common zeros, channel identifiability condition, forced spectral diversity 1

Modeling Water Flux at the Base of the Rooting Zone for Soils with Varying Glacial Parent Materials

Poster presented at American Geophysical Union meeting in 2013.Soils of varying glacial parent materials in the Great Lakes Region (USA) are characterized by thin unsaturated zones and widespread use of agricultural pesticides and nutrients that affect shallow groundwater. To better our understanding of the fate and transport of contaminants, improved models of water fluxes through the vadose zones of various hydrogeologic settings are warranted. Furthermore, calibrated unsaturated zone models can be coupled with watershed models, providing a means for predicting the impact of varying climate scenarios on agriculture in the region. To address these issues, a network of monitoring sites was developed in Indiana that provides continuous measurements of precipitation, potential evapotranspiration (PET), soil volumetric water content (VWC), and soil matric potential to parameterize and calibrate models. Flux at the base of the root zone is simulated using two models of varying complexity: 1) the HYDRUS model, which numerically solves the Richards equation, and 2) the soil-water-balance (SWB) model, which assumes vertical flow under a unit gradient with infiltration and evapotranspiration treated as separate, sequential processes. Soil hydraulic parameters are determined based on laboratory data, a pedo-transfer function (ROSETTA), field measurements (Guelph permeameter), and parameter optimization. Groundwater elevation data are available at three of six sites to establish the base of the unsaturated zone model domain. Initial modeling focused on the groundwater recharge season (Nov–Feb) when PET is limited and much of the annual vertical flux occurs. HYDRUS results indicate that base of root zone fluxes at a site underlain by glacial ice-contact parent materials are 48% of recharge season precipitation (VWC RMSE=8.2%), while SWB results indicate that fluxes are 43% (VWC RMSE=3.7%). Due in part to variations in surface boundary conditions, more variable fluxes were obtained for a site underlain by alluvium with the SWB model (68% of recharge season precipitation, VWC RMSE=7.0%) predicting much greater drainage than HYDRUS (38% of recharge season precipitation, VWC RMSE=6.6%). Results also show that when calculating drainage flux over the recharge period, HYDRUS is highly sensitive to model initialization using observed water content from in-situ instrumentation. Simulated recharge season drainage flux is as much as 3.5 times higher when a one-month spin-up period was performed in the HYDRUS model for the same site. SWB results are less sensitive to water content initialization, but drainage flux is 1.6 times higher at one site using the same spin-up analysis. The long-term goals of this effort are to leverage the robust calibration data set to establish optimal approaches for determining hydraulic parameters such that water fluxes in the lower vadose zone can be modeled for a wider range of geomorphic settings where calibration data are unavailable

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead