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DOE OSTI2016

Cost-Effectiveness Analysis of the Residential Provisions of the 2015 IECC for South Dakota

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2015 edition of the International Energy Conservation Code (IECC), relative to the 2012 and 2009 IECC for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhomes, and low-rise multifamily residential buildings covered by the residential provisions of the 2015 IECC. These reports were originally published in October 2015, and revised in February 2016 to update numbers reported in certain results tables.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2016

Cost-Effectiveness Analysis of the Residential Provisions of the 2015 IECC for West Virginia

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2015 edition of the International Energy Conservation Code (IECC), relative to the 2012 and 2009 IECC for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhomes, and low-rise multifamily residential buildings covered by the residential provisions of the 2015 IECC. These reports were originally published in October 2015, and revised in February 2016 to update numbers reported in certain results tables.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2016

Cost-Effectiveness Analysis of the Residential Provisions of the 2015 IECC for Wisconsin

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2015 edition of the International Energy Conservation Code (IECC), relative to the 2012 and 2009 IECC for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhomes, and low-rise multifamily residential buildings covered by the residential provisions of the 2015 IECC. These reports were originally published in October 2015, and revised in February 2016 to update numbers reported in certain results tables.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2016

Cost-Effectiveness Analysis of the Residential Provisions of the 2015 IECC for Wyoming

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2015 edition of the International Energy Conservation Code (IECC), relative to the 2012 and 2009 IECC for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhomes, and low-rise multifamily residential buildings covered by the residential provisions of the 2015 IECC. These reports were originally published in October 2015, and revised in February 2016 to update numbers reported in certain results tables.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2025

SPRUCE Vegetation Phenology in Experimental Plots from PhenoCam Imagery, 2015-2024

This data set consists of PhenoCam data from the SPRUCE experiment from the beginning of whole ecosystem warming (Hanson et al. 2017) in August 2015 through March 31 of 2025 (2015-08-24 to 2025-03-31), with start- and end-of-season phenological transition dates derived through the end of autumn 2024. Digital cameras, or phenocams, installed in each SPRUCE enclosure track seasonal variation in vegetation “greenness”, a proxy for vegetation phenology and associated physiological activity. Three separate regions of interest (ROIs) were defined for each camera field of view, corresponding to different vegetation types and demarcating (1) Picea trees (vegetation type EN, for evergreen needleleaf); (2) Larix trees (vegetation type DN, for deciduous needleleaf); and (3) the mixed shrub layer (vegetation type SH). This data set consists of three sets of data files: (1) 3-day summary product files: One file for each camera and each ROI (i.e. vegetation type), characterizing vegetation color at a 3-day time step. • Contains 36 files in *.csv format inside a compressed (*.zip) file. (2) Transition date file: Estimates “greenness rising” (spring) and “greenness falling” (autumn) transition dates derived from the smoothed daily green chromatic coordinate (GCC) values, for each camera and each ROI (i.e., vegetation type). • Contains one file in *.csv format. (3) Snow flag files: Indicate days with snow on trees or snow on ground for each experimental enclosure. • Contains two files in *.csv format, one for snow on trees and one for snow on ground. This data set consists of two sets of companion files: (1) Accompanying HTML files show the 90th quantiles of the mean GCC plotted together with transition dates for each vegetation type and plot. • Contains three files in HTML format, one for each vegetation type. • One additional file in HTML format with the transition dates plotted for each vegetation type, by year. (2) R files for processing PhenoCam files and flags. • Contains five files in R file(*.R) format and the components of the phenocamr package (Version 1.1.4) used for calculating transition dates for 2015-2024. These are contained in a compressed (*.zip) file. User Note: All imagery is posted in near-real time to the PhenoCam Project web page (https://phenocam.nau.edu), where it is publicly available. Scroll to “spruce” in the Gallery or link directly to the 29 SPRUCE cameras at https://tinyurl.com/sprucecams. This data set is based on the complete camera record from SPRUCE and supersedes all previously released PhenoCam datasets (see Related Data Sets). The estimated transition dates for previously released datasets may differ slightly (in most cases, by ±3 days or less), because following standard PhenoCam processing protocols (Richardson et al. 2018, Scientific Data), smoothing and interpolation, outlier removal, and transition date estimation are always conducted using the full data record.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

Species-Specific Shifts in Diurnal Sap Velocity Dynamics and Hysteretic Behavior of Ecophysiological Variables During the 2015–2016 El Niño Event in the Amazon Forest

Current climate change scenarios indicate warmer temperatures and the potential for more extreme droughts in the tropics, such that a mechanistic understanding of the water cycle from individual trees to landscapes is needed to adequately predict future changes in forest structure and function. In this study, we contrasted physiological responses of tropical trees during a normal dry season with the extreme dry season due to the 2015–2016 El Niño-Southern Oscillation (ENSO) event. We quantified high resolution temporal dynamics of sap velocity (V s ), stomatal conductance (g s ) and leaf water potential (Ψ L ) of multiple canopy trees, and their correlations with leaf temperature (T leaf ) and environmental conditions [direct solar radiation, air temperature (T air ) and vapor pressure deficit (VPD)]. The experiment leveraged canopy access towers to measure adjacent trees at the ZF2 and Tapajós tropical forest research (near the cities of Manaus and Santarém). The temporal difference between the peak of g s (late morning) and the peak of VPD (early afternoon) is one of the major regulators of sap velocity hysteresis patterns. Sap velocity displayed species-specific diurnal hysteresis patterns reflected by changes in T leaf . In the morning, T leaf and sap velocity displayed a sigmoidal relationship. In the afternoon, stomatal conductance declined as T leaf approached a daily peak, allowing Ψ L to begin recovery, while sap velocity declined with an exponential relationship with Tleaf. In Manaus, hysteresis indices of the variables T leaf -T air and Ψ L -T leaf were calculated for different species and a significant difference (p < 0.01, α = 0.05) was observed when the 2015 dry season (ENSO period) was compared with the 2017 dry season (“control scenario”). In some days during the 2015 ENSO event, T leaf approached 40°C for all studied species and the differences between T leaf and T air reached as high at 8°C (average difference: 1.65 ± 1.07°C). Generally, T leaf was higher than T air during the middle morning to early afternoon, and lower than T air during the early morning, late afternoon and night. Our results support the hypothesis that partial stomatal closure allows for a recovery in Ψ L during the afternoon period giving an observed counterclockwise hysteresis pattern between Ψ L and T leaf .

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2017

IMAGING OBSERVATIONS OF THE HYDROGEN COMA OF COMET 67P/CHURYUMOV–GERASIMENKO IN 2015 SEPTEMBER BY THE PROCYON/LAICA

The water production rate of a comet is one of the fundamental parameters necessary to understand cometary activity when a comet approaches the Sun within 2.5 au, because water is the most abundant icy material in the cometary nucleus. Wide-field imaging observations of the hydrogen Lyα emission in comet 67P/Churyumov–Gerasimenko were performed by the Lyman Alpha Imaging Camera (LAICA) on board the 50 kg class micro spacecraft, the Proximate Object Close Flyby with Optical Navigation (PROCYON), on UT 2015 September 7.40, 12.37, and 13.17 (corresponding to 25.31, 30.28, and 31.08 days after the perihelion passage of the comet, respectively). We derive the water production rates, Q{sub H{sub 2O}}, of the comet from Lyα images of the comet by using a 2D axi-symmetric Direct Simulation Monte-Carlo model of the atomic hydrogen coma; (1.46 ± 0.47) × 10{sup 28}, (1.24 ± 0.40) × 10{sup 28}, and (1.30 ± 0.42) × 10{sup 28} molecules s{sup −1} on 7.40, 12.37, and 13.17 September, respectively. These values are comparable to the values from in situ measurements by the Rosetta instruments in the 2015 apparition and the ground-based and space observations during the past apparitions. The comet did not show significant secular change in average water production rates just after the perihelion passage for the apparitions from 1982 to 2015. We emphasize that the measurements of absolute Q{sub H{sub 2O}} based on the wide field of view (e.g., by the LAICA/PROCYON) are so important to judge the soundness of the coma models used to infer Q{sub H{sub 2O}} based on in situ measurements by spacecraft, like the Rosetta.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2017

High-energy Gamma-Ray Activity from V404 Cygni Detected by AGILE during the 2015 June Outburst

The AGILE satellite detected transient high-energy γ -ray emission from the X-ray binary V404 Cygni, during the 2015 June outburst observed in radio, optical, X-ray, and soft γ -ray frequencies. The activity was observed by AGILE in the 50–400 MeV energy band, between 2015 June 24 UT 06:00:00 and 2015 June 26 UT 06:00:00 (MJD 57197.25–57199.25), with a detection significance of ∼4.3 σ . The γ -ray detection, consistent with a contemporaneous observation by Fermi -LAT, is correlated with a bright flare observed at radio and hard X-ray frequencies, and with a strong enhancement of the 511 keV line emission, possibly indicating plasmoid ejections in a lepton-dominated transient jet. The AGILE observations of this binary system are compatible with a microquasar scenario in which transient jets are responsible for the high-energy γ -ray emission.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2019

The El Niño event of 2015–2016: climate anomalies and their impact on groundwater resources in East and Southern Africa

The impact of climate variability on groundwater storage has received limited attention despite widespread dependence on groundwater as a resource for drinking water, agriculture and industry. Here, we assess the climate anomalies that occurred over Southern Africa (SA) and East Africa, south of the Equator (EASE), during the major El Niño event of 2015–2016, and their associated impacts on groundwater storage, across scales, through analysis of in situ groundwater piezometry and Gravity Recovery and Climate Experiment (GRACE) satellite data. At the continental scale, the El Niño of 2015–2016 was associated with a pronounced dipole of opposing rainfall anomalies over EASE and Southern Africa, north–south of ~12°S, a characteristic pattern of the El Niño–Southern Oscillation (ENSO). Over Southern Africa the most intense drought event in the historical record occurred, based on an analysis of the cross-scale areal intensity of surface water balance anomalies (as represented by the standardised precipitation evapotranspiration index – SPEI), with an estimated return period of at least 200 years and a best estimate of 260 years. Climate risks are changing, and we estimate that anthropogenic warming only (ignoring changes to other climate variables, e.g. precipitation) has approximately doubled the risk of such an extreme SPEI drought event. These surface water balance deficits suppressed groundwater recharge, leading to a substantial groundwater storage decline indicated by both GRACE satellite and piezometric data in the Limpopo basin. Conversely, over EASE during the 2015–2016 El Niño event, anomalously wet conditions were observed with an estimated return period of ~10 years, likely moderated by the absence of a strongly positive Indian Ocean zonal mode phase. The strong but not extreme rainy season increased groundwater storage, as shown by satellite GRACE data and rising groundwater levels observed at a site in central Tanzania. We note substantial uncertainties in separating groundwater from total water storage in GRACE data and show that consistency between GRACE and piezometric estimates of groundwater storage is apparent when spatial averaging scales are comparable. These results have implications for sustainable and climate-resilient groundwater resource management, including the potential for adaptive strategies, such as managed aquifer recharge during episodic recharge events.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1996

High-Speed Civil Transport Forecast: Simulated Airlines Scenarios for Mach 1.6, Mach 2.0, and Mach 2.4 Configurations for Year 2015

The report describes the development of a database of fuel burn and emissions from projected High Speed Civil Transport (HSCT) fleets that reflect actual airlines' networks, operational requirement, and traffic flow as operated by simulated world wide airlines for Mach 1.6, 2.0, and 2.4 HSCT configurations. For the year 2015, McDonnell Douglas Corporation created two supersonic commercial air traffic networks consisting of origin-destination city pair routes and associated traffic levels. The first scenario represented a manufacturing upper limit producible HSCT fleet availability by year 2015. The fleet projection of the Mach 2.4 configuration for this scenario was 1059 units with a traffic capture of 70 percent. The second scenario focused on the number of units that can minimally be produced by the year 2015. Using realistic production rates, the HSCT fleet projection amounts to 565 units. The traffic capture associated with this fleet was estimated at 40 percent. The airlines network was extracted from the actual networks of 21 major world airlines. All the routes were screened for suitability for HSCT operations. The route selection criteria included great circle distance, difference between flight path distance and great circle distance to avoid overland operations, and potential flight frequency.

Metwally, Munir↗
NASA NTRS2015

TA-13: Ground and Launch Systems, 2015 NASA Technology Roadmaps

This presentation is a summary of new content contained in the 2015 update of Technology Area-13, Ground and Launch Systems technology roadmap beyond the content contained in the 2010 version. Also included are brief assessments of benefits, alignments, challenges, technical risk and reasonableness, sequencing and timing, and time and effort to achieve goals. This presentation is part of overall presentations of new content only for the 2015 update of the 15 NASA Technology Roadmaps that will be conducted in a public forum managed by the National Research Council on September 28-29, 2015. The 15 roadmaps have already been publically released via the STI process.

decision-making tools↗
NASA NTRS2016

Advanced Technologies for Robotic Exploration Leading to Human Exploration: Results from the SpaceOps 2015 Workshop

This paper will provide a summary and analysis of the SpaceOps 2015 Workshop all-day session on "Advanced Technologies for Robotic Exploration, Leading to Human Exploration", held at Fucino Space Center, Italy on June 12th, 2015. The session was primarily intended to explore how robotic missions and robotics technologies more generally can help lead to human exploration missions. The session included a wide range of presentations that were roughly grouped into (1) broader background, conceptual, and high-level operations concepts presentations such as the International Space Exploration Coordination Group Roadmap, followed by (2) more detailed narrower presentations such as rover autonomy and communications. The broader presentations helped to provide context and specific technical hooks, and helped lay a foundation for the narrower presentations on more specific challenges and technologies, as well as for the discussion that followed. The discussion that followed the presentations touched on key questions, themes, actions and potential international collaboration opportunities. Some of the themes that were touched on were (1) multi-agent systems, (2) decentralized command and control, (3) autonomy, (4) low-latency teleoperations, (5) science operations, (6) communications, (7) technology pull vs. technology push, and (8) the roles and challenges of operations in early human architecture and mission concept formulation. A number of potential action items resulted from the workshop session, including: (1) using CCSDS as a further collaboration mechanism for human mission operations, (2) making further contact with subject matter experts, (3) initiating informal collaborative efforts to allow for rapid and efficient implementation, and (4) exploring how SpaceOps can support collaboration and information exchange with human exploration efforts. This paper will summarize the session and provide an overview of the above subjects as they emerged from the SpaceOps 2015 Workshop session.

space operations↗
NASA NTRS2016

NASA Environmental Control and Life Support Technology Development and Maturation for Exploration: 2015 to 2016 Overview

Over the last year, the National Aeronautics and Space Administration (NASA) has continued to refine the understanding and prioritization of technology gaps that must be closed in order to achieve Evolvable Mars Campaign objectives and near term objectives in the cislunar proving ground. These efforts are reflected in updates to the technical area roadmaps released by NASA in 2015 and have guided technology development and maturation tasks that have been sponsored by various programs. This paper provides an overview of the refined Environmental Control and Life Support (ECLS) strategic planning, as well as a synopsis of key technology and maturation project tasks that occurred in 2014 and early 2015 to support the strategic needs. Plans for the remainder of 2015 and subsequent years are also described.

Schneider, Walter F.↗
NASA NTRS2016

Meteorite Falls Observed in U.S. Weather Radar Data in 2015 and 2016 (To Date)

To date, over twenty meteorite falls have been located in the weather radar imagery of the National Oceanic and Atmospheric Administration (NOAA)'s NEXRAD radar network. We present here the most prominent events recorded since the last Meteoritical Society meeting, covering most of 2015 and early 2016. Meteorite Falls: The following events produced evidence of falling meteorites in radar imagery and resulted in meteorites recovered at the fall site. Creston, CA (24 Oct 2015 0531 UTC): This event generated 218 eyewitness reports submitted to the American Meteor Society (AMS) and is recorded as event #2635 for 2015 on the AMS website. Witnesses reported a bright fireball with fragmentation terminating near the city of Creston, CA, north of Los Angeles. Sonic booms and electrophonic noise were reported in the vicinity of the event. Weather radar imagery records signatures consistent with falling meteorites in data from the KMUX, KVTX, KHNX and KVBX. The Meteoritical Society records the Creston fall as an L6 meteorite with a total recovered mass of 688g. Osceola, FL (24 Jan 2016 1527 UTC): This daytime fireball generated 134 eyewitness reports on AMS report number 266 for 2016, with one credible sonic boom report. The fireball traveled roughly NE to SW with a terminus location north of Lake City, FL in sparsely populated, forested countryside. Radar imagery shows distinct and prominent evidence of a significant meteorite fall with radar signatures seen in data from the KJAX and KVAX radars. Searchers at the fall site found that recoveries were restricted to road sites by the difficult terrain, and yet several meteorites were recovered. Evidence indicates that this was a relatively large meteorite fall where most of the meteorites are unrecoverable due to terrain. Osceola is an L6 meteorite with 991 g total mass recovered to date. Mount Blanco, TX (18 Feb 2016 0343 UTC): This event produced only 39 eyewitness reports and is recorded as AMS event #635 for 2016. No reports of sonic booms or electrophonic noise are recorded in the AMS eyewitness reports, but videos of the event show a relatively long-lasting fireball with fragmentation. Evidence of falling meteorites is seen in radar imagery from the KAMA and KLBB radars defining a roughly WNW to ESE trend with the dominant wind direction. This event featured favorable search ground composed mostly of farmland and ranchland and was extensively searched. Rather surprisingly, only a single L5 chondrite of 36.2g has been recovered to date.

Fries, Marc↗
NASA NTRS2016

Aura OMI observations of regional SO2 and NO2 pollution changes from 2005 to 2015

The Ozone Monitoring Instrument (OMI) onboard NASA's Aura satellite has been providing global observations of the ozone layer and key atmospheric pollutant gases, such as nitrogen dioxide (NO2/ and sulfur dioxide (SO2/, since October 2004. The data products from the same instrument provide consistent spatial and temporal coverage and permit the study of anthropogenic and natural emissions on local-to-global scales. In this paper, we examine changes in SO2 and NO2 over some of the world's most polluted industrialized regions during the first decade of OMI observations. In terms of regional pollution changes, we see both upward and downward trends, sometimes in opposite directions for NO2 and SO2, for different study areas. The trends are, for the most part, associated with economic and/or technological changes in energy use, as well as regional regulatory policies. Over the eastern US, both NO2 and SO2 levels decreased dramatically from 2005 to 2015, by more than 40 and 80 %, respectively, as a result of both technological improvements and stricter regulations of emissions. OMI confirmed large reductions in SO2 over eastern Europe's largest coal-fired power plants after installation of flue gas desulfurization devices. The North China Plain has the world's most severe SO2 pollution, but a decreasing trend has been observed since 2011, with about a 50% reduction in 2012- 2015, due to an economic slowdown and government efforts to restrain emissions from the power and industrial sectors. In contrast, India's SO2 and NO2 levels from coal power plants and smelters are growing at a fast pace, increasing by more than 100 and 50 %, respectively, from 2005 to 2015. Several SO2 hot spots observed over the Persian Gulf are probably related to oil and gas operations and indicate a possible underestimation of emissions from these sources in bottom-up emission inventories. Overall, OMI observations have proved valuable in documenting rapid changes in air quality over different parts of the world during last decade. The baseline established during the first 11 years of OMI is indispensable for the interpretation of air quality measurements from current and future satellite atmospheric composition missions.

Pollution trends↗
NASA NTRS2016

Highly Relativistic Radiation Belt Electron Acceleration, Transport, and Loss: Large Solar Storm Events of March and June 2015

Two of the largest geomagnetic storms of the last decade were witnessed in 2015. On 17 March 2015, a coronal mass ejection-driven event occurred with a Dst (Disturbance Storm Time Ring Current Index) value reaching 223 nanoteslas. On 22 June 2015 another strong storm (Dst reaching 204 nanoteslas) was recorded. These two storms each produced almost total loss of radiation belt high-energy (E (Energy) greater than or approximately equal to 1 millielectronvolt) electron fluxes. Following the dropouts of radiation belt fluxes there were complex and rather remarkable recoveries of the electrons extending up to nearly 10 millielectronvolts in kinetic energy. The energized outer zone electrons showed a rich variety of pitch angle features including strong butterfly distributions with deep minima in flux at alpha equals 90 degrees. However, despite strong driving of outer zone earthward radial diffusion in these storms, the previously reported impenetrable barrier at L (L-shell magnetic field line value) approximately equal to 2.8 was pushed inward, but not significantly breached, and no E (Energy) greater than or approximately equal to 2.0 millielectronvolts electrons were seen to pass through the radiation belt slot region to reach the inner Van Allen zone. Overall, these intense storms show a wealth of novel features of acceleration, transport, and loss that are demonstrated in the present detailed analysis.

Baker, D. N.↗
NASA NTRS2018

Impact of Aquarius and SMAP Sea Surface Salinity Observations on Seasonal Predictions of the 2015 El Nino

We assess the impact of satellite sea surface salinity (SSS) observations on dynamical ENSO forecasts for the big 2015 El Nino event. From March to June 2015, the availability of two overlapping satellite SSS instruments, Aquarius and SMAP (Soil Moisture Active Passive Mission), allows a unique opportunity to compare and contrast forecasts generated with the benefit of these two satellite SSS observation types. Four distinct experiments are presented that include 1) freely evolving model SSS (i.e. no satellite SSS), relaxation to 2) climatological SSS (i.e. WOA13 SSS), 3) Aquarius, and 4) SMAP initialization. Coupled hindcasts are then generated from these initial conditions for March 2015. These forecasts are then validated against observations and evaluated with respect to the observed El Nino development.

Hackert, E.↗
NASA NTRS2018

Impact of Aquarius and SMAP Sea Surface Salinity Observations on Seasonal Predictions of the 2015 El Nino

We assess the impact of satellite sea surface salinity (SSS) observations on dynamical ENSO forecasts for the big 2015 El Nino event. From March to June 2015, the availability of two overlapping satellite SSS instruments, Aquarius and SMAP, allows a unique opportunity to compare and contrast coupled forecasts generated with the benefit of these two satellite SSS observation types. Four distinct experiments are presented that include 1) freely evolving model SSS (i.e. no satellite SSS), relaxation to 2) climatological SSS (i.e. WOA13 (World Ocean Atlas 2013) SSS), 3) Aquarius and 4) SMAP initialization. Coupled hindcasts are generated from these initial conditions for March 2015. These forecasts are then validated against observations and evaluated with respect to the observed El Nino development.

Kovach, R.↗