Search NASA⌕ Search

SEARCH · Search NASA

Results for “Europe”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1989

Winter in Northern Europe (WINE). The project Winter in Northern Europe (MAP/WINE): Introduction and outlook

The project Winter in Northern Europe (WINE) of the international Middle Atmosphere Program (MAP) comprised a multinational study of the structure, dynamics and composition of the middle atmosphere in winter at high latitudes. Coordinated field measurements were performed during the winter 1983 to 1984 by a large number of ground-based, air-borne, rocket-borne and satellite-borne instruments. Many of the individual experiments were performed in the European sector of the high latitude and polar atmosphere. Studies of the stratosphere, were, in addition, expanded to hemispheric scales by the use of data obtained from remotely sensing satellites. Beyond its direct scientific results, which are reviewed, MAP/WINE has stimulated quite a number of follow-on experiments and projects which address the aeronomy of the middle atmosphere at high and polar latitudes.

Vonzahn, U.↗
DOE OSTI2020

2020 IEEE PES Innovative Smart Grid Technologies Europe (ISGT-Europe)

Recent proliferation of distributed energy sources in distribution or sub-transmission systems necessitates close monitoring of these three-phase power grids which typically operate under unbalanced loading conditions. Unlike the transmission systems where the network equations are commonly based on the positive sequence component models, a detailed three phase model will have to be used in implementing network applications for these systems. In the specific case of the state estimator, where measurement and parameter errors may bias the solution, bad data and parameter error detection algorithms should also be incorporated. Implementing the state estimator and error detection algorithms for three-phase systems impose additional computational burden and modifications to the state estimation code. This paper proposes a practical solution to avoid these issues by using synchronized phasor measurements and modal decoupling. The previously developed parameter error detection algorithm based on the normalized Lagrange multipliers (NLM) test is applied to the measurements independently in each mode in parallel, not only saving CPU time but also avoiding new code development for a three-phase estimator. Different parameter error scenarios are created and tested to verify the effectiveness of the proposed error detection approach.

Khalili, Ramtin↗
DOE OSTI2020

Trends and source apportionment of aerosols in Europe during 1980-2018

Aerosols have significantly affected health, environment, and climate in Europe. Aerosol concentrations have been declining since the 1980s in Europe,mainly owing to a reduction of local aerosol and precursor emissions.Emissions from other source regions of the world, which have been changing rapidly as well, may also perturb the historical and future trends of aerosols and change their radiative impact in Europe. This study examines trends of aerosols in Europe during 1980–2018 and quantifies contributions from 16 source regions using the Community Atmosphere Model version 5 with Explicit Aerosol Source Tagging (CAM5-EAST). The simulated near-surface total mass concentration of sulfate, black carbon, and primary organic carbon had a 62 % decrease during 1980–2018. The majority of which was contributed to reductions of local emissions in Europe, and 8 %–9 % was induced by a decrease in emissions from Russia–Belarus–Ukraine. With the decreases in the fractional contribution of local emissions, aerosols transported from other source regions are increasingly important for air quality in Europe. During 1980–2018, the decrease in sulfate loading led to a warming effect of 2.0 W m –2 in Europe, with 12 % coming from changes in non-European sources, especially from North America and Russia–Belarus–Ukraine. According to the Shared Socioeconomic Pathways (SSP) scenarios, contributions to the sulfate radiative forcing over Europe from both local European emissions and non-European emissions should decrease at a comparable rate in the next 3 decades, suggesting that future changes in non-European emissions are as important as European emissions for causing possible regional climate change associated with aerosols in Europe.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

One hundred priority questions for advancing seagrass conservation in Europe

Societal Impact Statement Seagrass ecosystems are of fundamental importance to our planet and wellbeing. Seagrasses are marine flowering plants, which engineer ecosystems that provide a multitude of ecosystem services, for example, blue foods and carbon sequestration. Seagrass ecosystems have largely been degraded across much of their global range. There is now increasing interest in the conservation and restoration of these systems, particularly in the context of the climate emergency and the biodiversity crisis. The collation of 100 questions from experts across Europe could, if answered, improve our ability to conserve and restore these systems by facilitating a fundamental shift in the success of such work. Summary Seagrass meadows provide numerous ecosystem services including biodiversity, coastal protection, and carbon sequestration. In Europe, seagrasses can be found in shallow sheltered waters along coastlines, in estuaries & lagoons, and around islands, but their distribution has declined. Factors such as poor water quality, coastal modification, mechanical damage, overfishing, land‐sea interactions, climate change and disease have reduced the coverage of Europe’s seagrasses necessitating their recovery. Research, monitoring and conservation efforts on seagrass ecosystems in Europe are mostly uncoordinated and biased towards certain species and regions, resulting in inadequate delivery of critical information for their management. Here, we aim to identify the 100 priority questions, that if addressed would strongly advance seagrass monitoring, research and conservation in Europe. Using a Delphi method, researchers, practitioners, and policymakers with seagrass experience from across Europe and with diverse seagrass expertise participated in the process that involved the formulation of research questions, a voting process and an online workshop to identify the final list of the 100 questions. The final list of questions covers areas across nine themes: Biodiversity & Ecology; Ecosystem services; Blue carbon; Fishery support; Drivers, Threats, Resilience & Response; Monitoring & Assessment; Conservation & Restoration; Governance, Policy & Management; and Communication. Answering these questions will fill current knowledge gaps and place European seagrass onto a positive trajectory of recovery.

Nordlund, Lina Mtwana↗
NASA NTRS2001

The Extremely Warm Early Winter 2000 in Europe: What is the Forcing

High variability characterizes the winter climate of central Europe: interannual fluctuations in the surface-air temperature as large as 18 C over large areas are fairly common. The extraordinary early-winter 2000 in Europe appears to be a departure to an unprecedented extreme of the existing climate patterns. Such anomalous events affect agriculture, forestry, fuel consumption, etc., and thus deserve in-depth analysis. Our analysis indicates that the high anomalies of the surface-air temperature are predominantly due to the southwesterly flow from the eastern North Atlantic, with a weak contribution by southerly flow from the western Mediterranean. Backward trajectories based on the SSM/I and NCEP Reanalysis datasets traced from west-central Europe indicate that the warm air masses flowing into Europe originate in the southern North Atlantic, where the surface-air temperatures exceed by 15c or more the climatic norms in Europe for late-November or early-December. Because such large ocean-to-continent temperature differences characterize the winter conditions, we refer to this episode which started in late November as occurring in the early winter. In this season, with the sun low over the horizon in Europe, absorption of insolation by the surface has little significance. The effect of cloudiness, a corollary to the low-level maritime-air advection, is a warming by a reduction of heat loss (greenhouse effect). In contrast, in the summer, clouds, by reducing absorption of insolation, produce a cooling, effect at the surface.

Otterman, J.↗
NASA NTRS2002

North Atlantic Surface Winds Examined as the Source of Warm Advection into Europe in Winter

When from the southwest, North Atlantic ocean surface winds are known to bring warm and moist airmasses into central Europe in winter. By tracing backward trajectories from western Europe, we establish that these airmasses originate in the southwestern North Atlantic, in the very warm regions of the Gulf Stream. Over the eastern North Atlantic, Lt the gateway to Europe, the ocean-surface winds changed directions in the second half of the XXth century, those from the northwest and from the southeast becoming so infrequent, that the direction from the southwest became even more dominant. For the January-to-March period, the strength of south-westerlies in this region, as well as in the source region, shows in the years 1948-1995 a significant increase, above 0.2 m/sec/ decade. Based on the sensitivity of the surface temperature in Europe, slightly more than 1 C for a 1m/sec increase in the southwesterly wind, found in the previous studies, the trend in the warm advection accounts for a large part of the warming in Europe established for this period in several reports. However, for the most recent years, 1996-2001, the positive trend in the southwesterly advection appears to be is broken, which is consistent with unseasonally cold events reported in Europe in those winters. This study had, some bearing on evaluating the respective roles of the North Atlantic Oscillation and the Greenhouse Gas Global warming, GGG, in the strong winter warming observed for about half a century over the northern-latitude continents. Changes in the ocean-surface temperatures induced by GGG may have produced the dominant southwesterly direction of the North Atlantic winds. However, this implies a monotonically (apart from inherent interannual variability) increasing advection, and if the break in the trend which we observe after 1995 persists, this mechanism is counter-indicated. The 1948-1995 trend in the south-westerlies could then be considered to a large degree attributable to the North Atlantic Oscillation.

Otterman, J.↗
DOE OSTI2020

Overview of the Long-Term Stewardship of the Remediated Uranium Mining and Milling Sites in Europe - 20079

Uranium mining in Europe began in the ' 40's for civil and military applications. The great majority of the uranium mines have now been closed and are going through the stages of decommissioning and/or rehabilitation. Today, the main uranium producers are outside the EU; only a few mines are still in operation inside the EU. In 2006, the situation of the uranium mines and mill tailings in Europe, identifying the tailings liabilities, their status, the plans for these sites and any associated hazards, was reported to the EC. The legacy of uranium mines and mill tailing disposals in the EU are located mainly in 12 Member States where, in total, 87 tailing objects were identified at 63 sites. The volume of each one of these tailings disposal varies from a few thousand to several tens of million m{sup 3}. The majority of these sites are no longer in operation. More than 40 tailing embankments have already been completely remediated. Approximately 20 are currently being remediated while for the remaining objects, remediation has yet to start. After ten years, and for a few cases where the respective projects have not yet been completed, it seems that most of Europe's uranium mines and milling legacies were remediated according to acceptable environmental standards. Nevertheless, Europe is about to face a new challenge that comes from the concluded remediation projects for which an effective set of measures for coordinated institutional control, known as 'long-term stewardship', is needed including, in most cases, continuous and active maintenance. Moreover, the uncertainty of what will happen to these sites if institutional control fails at some point in time is a major concern. This work presents a summary of the situation and current issues of the uranium mine and mill tailings in Europe and their remediation status. It addresses not only the management of existing uranium mine and mill legacies but also the methods and strategies that have been used to prevent the creation of new future legacy sites from uranium mines still in operation. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS2001

Are Stronger North-Atlantic Southwesterlies the Forcing to the Late-Winter Warming in Europe?

We examine a possible mechanism leading to late-winter warming and thus to an early spring in Europe. From the NCEP Reanalysis, we extract for the years 1948-1999 ocean-surface winds over the eastern North Atlantic, and air temperatures at the surface, T(sub s), and at the 500 mb level, T(sub 500), in late-winter and spring. T(sub s) is extracted at six European locations, all at 50.5 N, ranging in longitude from 1.9 E (northeastern France) to 26.2 E (Ukraine). To quantify the advection of maritime air into Europe, we evaluate for 3-pentad groups the Index I(sub na) of the southwesterlies at 45 N; 20 W: I(sub na) is the average wind speed at this point if the direction is from the quadrant 180-270 deg (when the direction is different, the contribution counts as zero). In late winter correlations C(sub it) between the Index I(sub na) and the temperature T(sub s) are substantial, up to the 0.6 level, in western Europe (but weaker correlations for Poland and Ukraine). C(sub it) drops sharply by mid-March, taking occasionally negative values subsequently. This drop in C(sub it) indicates that maritime air advection is no longer associated closely with the surface-air warming, the role of immolation becomes important, and thus the drop in C(sub it) marks the arrival of spring. Correlations C(sub i delta) between I(sub na) and our lapse-rate parameter delta, the difference between T(sub s) and T(sub 500), indicate that the flow of warm maritime-air from the North Atlantic into this 'corridor' at 50.5 N is predominantly at low tropospheric level. By computing the best linear fit to I(sub na) and T(sub s), the trends for the period 1948-1999 are evaluated. The trends are appreciable in the second half of February and the first half of March. Our 3-pentad analysis points to the interval from mid-February to mid-March as the end-of-winter period in which the southwesterlies over the eastern North Atlantic become stronger and the surface-air temperatures in Europe rise markedly, the lapse rate becomes steeper, and concurrently the longitudinal temperature gradient between the Somme (France) and the Oder (Germany/Poland border) is reduced by 0.8 C, that is, by 20% of its 1948 value. Our thesis, that the observed late-winter warming and the corollary advancement of spring in Europe resulted at least in part from stronger southwesterlies over the North Atlantic, merits further investigations.

Otterman, J.↗
NASA NTRS2002

The 1996-2002 Plunge in the North-Atlantic Oscillation Index Produces Cold Spring Temperatures in Central Europe

Surface-air temperatures in winter and spring in central Europe rose over the second half of the 20th century, reported for different data-spans, and by different approaches (Ross et al., 1996; Angell, 1999; Hansen et al., 1999; Demaree et al., 2002). Analysis with a finer temporal resolution shows that late-winter and early-spring (February and March) trends are much stronger than the 3-month season averages (Otterman et al., 2002a). Responding to this need for finer than 3- month resolution, observations at meteorological stations in central Europe are analyzed here for the years 1951-2002, computing six-pentad (5-day period) averages (effectively monthly averages for January, February, and March). The daily minimum surface-air temperature, T(sub min), and the daily maximum temperature, T(sub max), rose steeply in Berlin and Poznan' in the years 1951-1995. Based on sensitivity studies, the bulk of this sharp warming is due to stronger southwesterlies over the North Atlantic, with which the temperatures in Europe are strongly correlated (Otterman et al., 1999; 2002a). However, for the most recent seven years, a pronounced downturn of the warming is observed, which we attribute to the concurrent, 1996-2002, sharp downturn of the ocean-surface southwesterlies over the North Atlantic (Otterman et al., 2002b). Such changes in the ocean winds and variations in the storm tracks are associated with changes in the North Atlantic Oscillation, NAO (Rogers, 1997). The NAO index, the difference in the surface pressure between Iceland and Azores, constitutes a measure of the zonal winds over the eastern North Atlantic, and thus is a critically important factor influencing the flow of maritime air into Europe (but the temperature of the advected airmasses depends on the meridional component, as we discuss). The recent (1996-2002) downturn in this index resulted in much colder spring temperatures in Europe, with adverse significance for the growing season.

Atlas, Robert↗
NASA NTRS2021

Changing Hydroclimate Dynamics and the 19th to 20th Century Wetting Trend in the English Channel Region of Northwest Europe

Northwestern Europe has experienced a trend of increasingly wet winters over the past 150 years, with few explanations for what may have driven this hydroclimatic change. Here we use the Old World Drought Atlas (OWDA), a tree-ring based reconstruction of the self-calibrating Palmer Drought Severity Index (scPDSI), to examine this wetting trend and place it in a longer hydroclimatic context. We find that scPDSI variability in northwestern Europe is strongly correlated with the leading mode of the OWDA during the last millennium (1000–2012). This leading mode, here named the ‘English Channel’ (EC) mode, has pronounced variability on interannual to centennial timescales and has an expression in scPDSI similar to that of the East Atlantic teleconnection pattern. A shift in the EC mode from a prolonged negative phase to more neutral conditions during the 19th and 20th centuries is associated with the wetting trend over its area of influence in England, Wales, and much of northern continental Europe. The EC mode is the dominant scPDSI mode from approximately 1000–1850, after which its dominance waned in favor of the secondary ‘North–South’ (NS) mode, which has an expression in scPDSI similar to that of the winter North Atlantic Oscillation (NAO). We examine the dynamical nature of both of these modes and how they vary on interannual to centennial timescales. Our results provide insight into the nature of hydroclimate variability in Europe before the widespread availability of instrumental observations.

hydroclimate↗
DOE OSTI2018

Teleconnection between mean sea level pressure in the North Atlantic for September, the AMO phase and mean temperature in Central Europe for December (1896–2015)

According to the present study, an atmospheric teleconnection is likely to exist between mean sea level pressure (MSLP) in the North Atlantic at early autumn (September) and temperature in Central Europe at early winter (December) based on the last 120 years. Atlantic Multidecadal Oscillation (AMO) might play an important role in this teleconnection, determining its direction. During a positive AMO phase, a North Atlantic MSLP above average in September is frequently followed by a colder-than-average December in Central Europe (in 80% of cases) whereas a warmer-than-average December is often observed in Central Europe after an under-average MSLP in the North Atlantic in September. According to the present investigation, this is caused by a strong tendency for blocking patterns over Northern Europe (mostly over the British Isles and Scandinavia) in the last month of the year, in the first case, and a weak tendency for that, in the second case. During a negative AMO phase, this connection is less certain. In the strong negative AMO phase between 1903 and 1925, the connection became reversed compared with that observed during the positive AMO phase. However, it was significantly strong. Within the much weaker negative AMO phase between 1963 and 1994, the connection was weaker, but rather similar to that observed during positive AMO phases. Since the revealed atmospheric teleconnection is characterized by a three-month delay, it possesses a prognostic value and can be used to predict the probability of temperature anomaly.

Meteorology & Atmospheric Sciences↗
NASA NTRS1984

Geodynamics of crustal deformation and seismotectonic block movements in central Europe

Geological observations reveal the style of neotectonic near-surface stresses and deformations in central Europe. Seismic activity, focal depths and fault plane solutions of earthquakes indicate kinematic reactions within the crust. A crustal deformation model which may account for the Rhine graben systems and the associated seismotectonic block movements in Europe is presented. A computer aided tomography to gravity anomalies is used in determining the crustal stresses in central Europe. Tomographical interpretations of gravity data with respect to seismic stresses are discussed. Kinematics and dynamics are integrated to show that the measured regional stresses in central Europe are derivable from the convection generated traction on the boundary of the elastic spherical shell of the crust as inferred from satellite derived gravity data.

Liu, H. S.↗
DOE OSTI2021

Europe’s energy policy based on large-scale use of renewables most likely will require supplemental power supplies to balance their electrical power systems

Political decisions toward an increased role for renewable energy sources (wind & solar) in Europe will have an impact on the functioning of the electrical power systems that will have to be offset due to the inherent intermittent nature of renewable sources. The offset can be accomplished either through increasing non-renewable energy supply and production from other means, including purchasing Russian piped natural gas and LNG, or decreasing demand by curtailing power consumption. Europe likely will also need increased energy supplies to cover reduced gas production in the North Sea and Netherlands. Also, expected disconnection of Baltic states from the BRELL (Belarus-Russia-EstoniaLatvia-Lithuania) grid will force these countries to acquire electricity from Europe, resulting in increased demands on the European power grid that will require additional capacity to offset.

24 POWER TRANSMISSION AND DISTRIBUTION↗
NASA NTRS1989

Large-scale transport of a CO-enhanced air mass from Europe to the Middle East

On November 14, 1981, the shuttle-borne Measurement of Air Pollution from Satellites (MAPS) experiment observed a carbon monoxide (CO) enhanced air mass in the middle troposphere over the Middle East. The primary source of this polluted air was estimated by constructing adiabatic isentropic trajectories backwards from the MAPS measurement location over a 36 h period. The isentropic diagnostics indicate that CO-enhanced air was transported southeastward over the Mediterranean from an organized synoptic-scale weather regime, albeit of moderate intensity, influencing central Europe on November 12. Examination of the evolving synoptic scale vertical velocity and precipitation patterns during this period, in conjuction with Meteosat visible, infrared, and water vapor imagery, suggests that the presence of this disturbed weather system over Europe may have created upward transport of CO-enhanced air between the boundary-layer and midtropospheric levels, and subsequent entrainment in the large-scale northwesterly jet stream flow over Europe and the Mediterranean.

Connors, V. S.↗
NASA NTRS1992

Supervised fully polarimetric classification of the Black Forest test site: From MAESTROI to MAC Europe

A study on the performance of a supervised fully polarimetric maximum likelihood classifier for synthetic aperture radar (SAR) data when applied to a specific classification context: forest classification based on age classes and in the presence of a sloping terrain is presented. For the experimental part, the polarimetric AIRSAR data at P, L, and C-band, acquired over the German Black Forest near Freiburg in the frame of the 1989 MAESTRO-1 campaign and the 1991 MAC Europe campaign was used, MAESTRO-1 with an ESA/JRC sponsored campaign, and MAC Europe (Multi-sensor Aircraft Campaign); in both cases the multi-frequency polarimetric JPL Airborne Synthetic Aperture Radar (AIRSAR) radar was flown over a number of European test sites. The study is structured as follows. At first, the general characteristics of the classifier and the dependencies from some parameters, like frequency bands, feature vector, calibration, using test areas lying on a flat terrain are investigated. Once it is determined the optimal conditions for the classifier performance, we then move on to the study of the slope effect. The bulk of this work is performed using the Maestrol data set. Next the classifier performance with the MAC Europe data is considered. The study is divided into two stages: first some of the tests done on the Maestro data are repeated, to highlight the improvements due to the new processing scheme that delivers 16 look data. Second we experiment with multi images classification with two goals: to assess the possibility of using a training set measured from one image to classify areas in different images; and to classify areas on critical slopes using different viewing angles. The main points of the study are listed and some of the results obtained so far are highlighted.

Degrandi, G.↗
NASA NTRS1993

Application of MAC-Europe AVIRIS data to the analysis of various alteration stages in the Landdmannalauger Hydrothermal Area (South Iceland)

In June 1991 extensive airborne remote sensing data-sets have been acquired over Iceland in the framework of the joint NASA/ESA Multisensor Airborne Campaign Europe (MAC-Europe). The study area is located within the Torfajokull central volcanic complex in South Iceland. This complex is composed by anomalously abundant rhyolitic acid volcanics, which underwent intensive hydrothermal alteration. Detailed studies of surface alteration of rhyolitic rocks in the area showed that all the major elements are leached as the rock is affected by complex mineralogical changes. Montmorillonite appears during the earliest stages of alteration. In the ultimate alteration product montmorillonite is absent and the rock consists mostly of amorphous silica, anatase, up to a volume of 50% kaolinite and variable amounts of native sulphur and pyrite. The case study presented shall endeavor to assess the potential of MAC-Europe AVIRIS and TMS data in determining a possible zonation of hydrothermal alteration in relationship to the active geo-thermal fields and structural features. To this end, the airborne data is analysed in comparison with laboratory spectral measurements of characteristics rock, soil, and vegetation samples collected in the study areaduring the summer of 1992. Various spectral mapping algorithms as well as unmixing approaches are tested and evaluated. Detailed geological and structural mapping as well as geochemical analysis of the main rock and soil types were performed to underpin the analysis of the airborne data.

Sommer, S.↗
NASA NTRS2000

Extreme Winter/Early-Spring Temperature Anomalies in Central Europe

Extreme seasonal fluctuations of the surface-air temperature characterize the climate of central Europe, 45-60 deg North Temperature difference between warm 1990 and cold 1996 in the January-March period, persisting for more than two weeks at a time, amounted to 18 C for extensive areas. These anomalies in the surface-air temperature stem in the first place from differences in the low level flow from the eastern North-Atlantic: the value of the Index 1na of southwesterlies over the eastern North-Atlantic was 8.0 m/s in February 1990, but only 2.6 m/ s in February 1996. The primary forcing by warm advection to positive anomalies in monthly mean surface temperature produced strong synoptic-scale uplift at the 700 mb level over some regions in Europe. The strong uplift contributed in 1990 to a much larger cloud-cover over central Europe, which reduced heat-loss to space (greenhouse effect). Thus, spring arrived earlier than usual in 1990, but later than usual in 1996.

Otterman, Joseph↗