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1

Shocks and cold fronts in galaxy clusters  

E-print Network

Table of contents (abridged): COLD FRONTS Origin and evolution of merger cold fronts Cold fronts in cluster cool cores . . . Simulations of gas sloshing. Origin of density discontinuity. . . . Effect of sloshing on cluster mass estimates and cooling flows. Zoology of cold fronts COLD FRONTS AS EXPERIMENTAL TOOL Velocities of gas flows Thermal conduction and diffusion across cold fronts Stability of cold fronts . . . Rayleigh-Taylor instability. Kelvin-Helmholtz instability. Possible future measurements using cold fronts . . . Plasma depletion layer and magnetic field. Effective viscosity of ICM. SHOCK FRONTS AS EXPERIMENTAL TOOL Cluster merger shocks Mach number determination Front width Mach cone and reverse shock? Test of electron-ion equilibrium . . . Comparison with other astrophysical plasmas Shocks and cluster cosmic ray population . . . Shock acceleration. Compression of fossil electrons. . . . Yet another method to measure intracluster magnetic field.

Maxim Markevitch; Alexey Vikhlinin

2007-04-24

2

HF Doppler and VHF radar observations of upper atmospheric disturbances caused by weak cold front during winter time  

NASA Technical Reports Server (NTRS)

The simultaneous use of the Taiwan VHF radar and the HF Doppler sounder for remote measurement of three-dimensional winds, gravity waves, and density perturbations at mesospheric and thermospheric heights is demonstrated. A special event of atmospheric disturbances caused by propagating gravity waves excited by weak convective motions in winter time were investigated. The three-dimensional wind velocities at different heights were determined, and the frequency, horizontal wavelength, vertical wavelength, and phase velocity of the gravity waves were measured. The subtropical, low-latitude site makes the VHF radar and HF Doppler array systems unique, and the observations especially valuable for space projects dealing with low-latitude atmosphere.

Hung, R. J.; Lee, C. C.; Gao, M.; Johnson, D. L.; Yang, F. W.

1990-01-01

3

Insulation grapes cold winter effect  

NASA Astrophysics Data System (ADS)

Purposes: The study of several insulation in cold conditions in Xinjiang Gobi Grape safe winter effect. Procedures and Method: The use of real-time U-plate thermometer to measure temperature changes recorded instrument to study the severe winter conditions, several insulation effect at different depths of grape root, and the cold resistance of winter grape roots at different depths variation; research in the coming year the spring and summer seasons, blooming the results of several insulation grape growth and development. Results: Several insulation Gobi Grape security winter better, surface temperature is largely improved compared with the control. The D900 collodions+ enhanced membrane to improve the 11.69°C, non-woven + buried improve the 10.09°C. D900 no glue cotton + enhanced membrane covering the grape surface <=-5°C continuous days of relatively non-woven + buried reduce eight days underground 30cm, a decrease of 5 days. D900 no glue cotton + Enhanced membrane covering the minimum grape underground temperature than the non-woven+ buried there is a significant improvement of the surface temperature has increased 1.57°C, the underground at 30 cm temperature has increased 1.08°C, 60cm, underground buried than the processing temperature has increased 1.54°C, the insulation effect. Conclusions: Xinjiang cold conditions, the D900 without glue cotton+ film way cover the grapes can live through the winter, is to protect the winter safety of the grapes and grape production.

Guo, Shao-jie; Li, Ming; Ying, Liang-fu

4

Cold fronts in cool core clusters  

E-print Network

Cold fronts have been detected both in merging and in cool core clusters, where little or no sign of a merging event is present. A systematic search of sharp surface brightness discontinuities performed on a sample of 62 galaxy clusters observed with XMM-Newton shows that cold fronts are a common feature in galaxy clusters. Indeed most (if not all) of the nearby clusters (z cold front. Understanding the origin and the nature of a such frequent phenomenon is clearly important. To gain insight on the nature of cold fronts in cool core clusters we have undertaken a systematic study of all contact discontinuities detected in our sample, measuring surface brightness, temperature and when possible abundance profiles across the fronts. We measure the Mach numbers for the cold fronts finding values which range from 0.2 to 0.9; we also detect a discontinuities in the metal profile of some clusters.

S. Ghizzardi; S. Molendi; M. Rossetti; A. Leccardi

2006-11-13

5

Compare and contrast warm and cold fronts  

NSDL National Science Digital Library

This pair of Earth science animations show students what happens at cold and warm fronts as clouds are formed by the interaction of warm air and cool air. The cool front animation depicts cumulonimbus clouds forming as a cold front moves into a region of warm air and forces the warm air to rise. In contrast, the warm front animation shows how warm air, moving over cold air, causes a progression of nimbostratus to cirrus clouds to form. Movie controls allow students to repeat, pause, or step through the animations, which can give students more time to analyze the images. Copyright 2005 Eisenhower National Clearinghouse

TERC. Center for Earth and Space Science Education

2003-01-01

6

Compare and Contrast Warm and Cold Fronts  

NSDL National Science Digital Library

In weather, fronts are defined as the boundaries between different air masses. Depending on the direction of movement and the characteristics of the air involved, different types of fronts form. This visualization shows the movement of warm and cold fronts as well as the characteristic clouds that are generated by each. A background essay and discussion questions are included.

7

Nitrogen and phosphorus transport between Fourleague Bay, LA, and the Gulf of Mexico: The role of winter cold fronts and Atchafalaya River discharge  

USGS Publications Warehouse

Nutrient fluxes were measured between Fourleague Bay, a shallow Louisiana estuary, and the Gulf of Mexico every 3 h between February 1 and April 30, 1994 to determine how high velocity winds associated with cold fronts and peak Atchafalaya River discharge influenced transport. Net water fluxes were ebb-dominated throughout the study because of wind forcing and high volumes of water entering the northern Bay from the Atchafalaya River. Flushing time of the Bay averaged <8 days; however, more rapid flushing occurred in response to northerly winds with approximately 56% of the volume of the Bay exported to the Gulf in 1 day during the strongest flushing event. Higher nitrate + nitrite (NO2+ NO3), total nitrogen (TN), and total phosphorus (TP) concentrations were indicative of Atchafalaya River input and fluxes were greater when influenced by high velocity northerly winds associated with frontal passage. Net exports of NO2 + NO3, TN, and TP were 43.5, 98.5, and 13.6 g s-1, respectively, for the 89-day study. An average of 10.6 g s-1 of ammonium (NH4) was exported to the Gulf over the study; however, concentrations were lower when associated with riverine influence and wind-driven exports suggesting the importance of biological processes. Phosphate (PO4) fluxes were nearly balanced over the study with fairly stable concentrations indicating a well-buffered system. The results indicate that the high energy subsidy provided by natural pulsing events such as atmospheric cold fronts and seasonal river discharge are efficient mechanisms of nutrient delivery to adjacent wetlands and nearshore coastal ecosystems and are important in maintaining coastal sustainability. ?? 2003 Elsevier Ltd. All rights reserved.

Perez, B.C.; Day, J.W., Jr.; Justic, D.; Twilley, R.R.

2003-01-01

8

Sequence of surface meteorological variables with the passage of winter cold fronts in the United States east of the Rocky Mountains  

E-print Network

); and Richmond, Virginia (RIC). (See Figure 1. ) To assure a sufficient sample size of &ontal passages for each city, three entire winters (October 1-March 31) were selected: 1996-97, 1997-98, and 1998-99. Through the National Climatic Data Center's (NCDC...

Huckaby, Daniel Dale

2001-01-01

9

Researchers Probe Why Colds Are More Likely in Winter  

MedlinePLUS

... features on this page, please enable JavaScript. Researchers Probe Why Colds Are More Likely in Winter Animal ... to congregate indoors with other people in smaller spaces -- could put people at an increased risk, rather ...

10

Cold Fronts in Clusters of Galaxies: Observations and Modeling  

NASA Technical Reports Server (NTRS)

Mergers of galaxy clusters -- some of the most energetic events in the Universe -- produce disturbances in hot intracluster medium, such as shocks and cold fronts, that can be used as tools to study the physics of galaxy clusters. Cold fronts may constrain viscosity and the structure and strength of the cluster magnetic fields. Combined with radio data, these observations also shed light on the production of ultrarelativistic particles that are known to coexist with the cluster thermal plasma. This talk will summarize the current X-ray observations of cluster mergers, as well as some recent radio data and high resolution hydrodynamic simulations.

Markevitch, Maxim

2012-01-01

11

The Impacts of Cold Front Passages on Louisiana Coastal Environments  

Microsoft Academic Search

Time-series measurements from stations along the Louisiana coast and inside the bays, estuaries and wetlands, from Atchafalaya Bay to the Mississippi River Delta, and synoptic satellite images from MODIS and other sensors, are used to investigate the impacts of cold front passages on the coastal aquatic environments and circulation. We examine the effects of wind on water level, currents, sediment

Z. Feng; C. Li; N. D. Walker

2008-01-01

12

Cyclone and cold front evolution over the Intermountain West  

NASA Astrophysics Data System (ADS)

Over the Intermountain West, cyclones and cold fronts can bring about dramatic sensible weather changes that impact the rapidly growing population of the region, yet the basic mechanisms contributing to their intensification and evolution are not well understood. This dissertation investigates these mechanisms using a multi-faceted approach that includes observational analysis, real-data model simulations, and idealized model simulations. Chapter 2 presents an observational analysis of the 15 Apr 2002 Tax Day Storm, which featured the strongest cyclone and cold front to pass through Salt Lake City, Utah in recent history. In particular, we establish the role of a newly identified feature, the Great Basin Confluence Zone (GBCZ), in cyclone and frontal evolution. This region of contraction (confluent deformation and divergence) extends downstream from the Sierra Nevada and is initially nonfrontal, but becomes the locus for frontogenesis and cyclogenesis. Chapter 3 uses real-data and idealized modeling studies to examine the role of the Sierra Nevada in Intermountain cold front evolution. Using model simulations of another strong case of Intermountain frontogenesis from 25 Mar 2006 with and without the Sierra Nevada, we show that the range produces a leeward warm anomaly, increasing the cross-front potential temperature contrast, and also enhances contraction along the front. Idealized baroclinic wave simulations in which we vary the initial cyclone position are used to show how the influence of the Sierra Nevada varies for differing synoptic patterns and frontal orientations. This work advances our understanding of the mechanisms important to cyclone and frontal evolution over mountainous terrain and should contribute to improved analysis and forecasting of cyclones and fronts over the Intermountain West.

West, Gregory Lucas

13

Fast Simulations of Gas Sloshing and Cold Front Formation  

NASA Technical Reports Server (NTRS)

We present a simplified and fast method for simulating minor mergers between galaxy clusters. Instead of following the evolution of the dark matter halos directly by the N-body method, we employ a rigid potential approximation for both clusters. The simulations are run in the rest frame of the more massive cluster and account for the resulting inertial accelerations in an optimised way. We test the reliability of this method for studies of minor merger induced gas sloshing by performing a one-to-one comparison between our simulations and hydro+N-body ones. We find that the rigid potential approximation reproduces the sloshing-related features well except for two artefacts: the temperature just outside the cold fronts is slightly over-predicted, and the outward motion of the cold fronts is delayed by typically 200 Myr. We discuss reasons for both artefacts.

Roediger, E.; ZuHone, J. A.

2011-01-01

14

Fast Simulations of Gas Sloshing and Cold Front Formation  

NASA Technical Reports Server (NTRS)

We present a simplified and fast method for simulating minor mergers between galaxy clusters. Instead of following the evolution of the dark matter halos directly by the N-body method, we employ a rigid potential approximation for both clusters. The simulations are run in the rest frame of the more massive cluster and account for the resulting inertial accelerations in an optimised way. We test the reliability of this method for studies of minor merger induced gas sloshing by performing a one-to-one comparison between our simulations and hydro+N-body ones. We find that the rigid potential approximation reproduces the sloshing-related features well except for two artifacts: the temperature just outside the cold fronts is slightly over-predicted, and the outward motion of the cold fronts is delayed by typically 200 Myr. We discuss reasons for both artifacts.

Roediger, E.; ZuHone, J. A.

2012-01-01

15

Mobile Bay response to a strong autumn cold front passage  

Microsoft Academic Search

Mobile Bay is a shallow embayment in Alabama bordering the northern Gulf of Mexico. A cold front passage during October 2000 decreased air temperatures from 27°C to 9°C and was accompanied by winds from the north in excess of 16 m\\/s. The winds generated a significant water level decrease throughout Mobile Bay over a three-day period. Water level decreases occurred

Richard L. Crout; Arne R. Diercks

2001-01-01

16

ORIGINAL PAPER Climatology of winter transition days for the contiguous  

E-print Network

as cold fronts and warm fronts during the winter season. Among the two less common subtypes, transition. The relative frequencies of wintertime warm and cold fronts have changed over the period 1951­2007. Relative cold front frequency has significantly increased in the Northeast and Midwest regions, and warm front

Sheridan, Scott

17

Introduction Winter colds, spring frosts and summer droughts  

E-print Network

Introduction Winter colds, spring frosts and summer droughts have been acknowledged as important (Áèòâèíñêàñ 1974, Áèòâèíñêàñ 1984), while the impact of sum- mer droughts have acquired greater attention only was noticed later (Bukantis et al. 2001). These trends and frequent intensive droughts were established also

18

Ram pressure stripping and the formation of cold fronts  

E-print Network

Chandra and XMM-Newton observations of many clusters reveal sharp discontinuities in the surface brightness, which, unlike shocks, have lower gas temperature on the X-ray brighter side of the discontinuity. For that reason these features are called ``cold fronts''. It is believed that some cold fronts are formed when a subcluster merges with another cluster and the ram pressure of gas flowing outside the subcluster gives the contact discontinuity the characteristic curved shape. While some edges may not arise directly from mergers (e.g., A496, Dupke & White, 2003), this paper focuses on those which arise as contact discontinuities between a merging subcluster and the ambient cluster gas. We argue that the flow of gas past the merging subcluster induces slow motions inside the cloud. These motions transport gas from the central parts of the subcluster towards the interface. Since in a typical cluster or group (even an isothermal one) the entropy of the gas in the central regions is significantly lower than in the outer regions, the transport of the low entropy gas towards the interface and the associated adiabatic expansion makes the gas temperature immediately inside the interface lower than in any other place in the system, thus enhancing the temperature jump across the interface and making the ``tip'' of the contact discontinuity cool. We illustrate this picture with the XMM-Newton gas temperature map of the A3667 cluster.

S. Heinz; E. Churazov; W. Forman; C. Jones; U. G. Briel

2003-08-08

19

Habitat suitability index models: greater white-fronted goose (wintering). [Anser albifrons  

Microsoft Academic Search

A review and synthesis of available information were used to develop models for indexing the potential suitability of agricultural and natural wetland habitats for wintering white-fronted geese (Anser albifrons). The model is scaled to produce indices of habitat suitability from 0 (unsuitable habitat) to 1.0 (optimal habitat) primarily for wintering habitat in southwest Louisiana and southwest Texas. Habitat suitability indices

Kaminski

1986-01-01

20

European Cold Winters and the Persistence of Atmospheric Blocking  

NASA Astrophysics Data System (ADS)

Cold winters over Western Europe can often be related to the existence of anomalous circulation patterns that involve prolonged easterly flow. Persistence of these anomalous conditions is crucial, for it takes several days to transport the cold air from Northern and Eastern Europe towards Western Europe. In a few historic cases these anomalous circulation conditions, in which the prevailing westerlies are temporarily 'blocked', existed for more than a month, thereby impacting significantly on regional climate. Climate models are known to have problems representing both frequency and persistence of these so-called blocking events. It is not clear whether increased resolution will solve this problem completely. Here we study the evolution and in particular the persistence of blocking episodes from a potential vorticity perspective. An analysis in terms of potential vorticity is attractive because of its lagrangian conservation properties under adiabatic conditions. Enhanced insight in the blocking dynamics may in turn increase or decrease confidence in current climate models.

de Vries, Hylke; Haarsma, Reindert; Hazeleger, Wilco

2010-05-01

21

Variable increases in cold hardiness induced in winter rape by plant growth regulators  

Microsoft Academic Search

Triazole and conventional growth regulators were tested for their ability to extend cold hardiness and improve the winter\\u000a survival of winter rape (Brassica napus L.). Winter rape plants were grown in the field (Ottawa 45°23? N) and in growth cabinets. Plant growth regulators (PGRs)\\u000a were applied during the early vegetative stage and the plants were allowed to cold harden. Cold-hardened

M. J. Morrison; C. J. Andrews

1992-01-01

22

The influence of shelf-sea fronts on winter monsoon over East China Sea  

NASA Astrophysics Data System (ADS)

Strong sea surface temperature fronts in open seas are known to affect the atmosphere. Shelf-sea fronts in winter have comparable strengths, yet their impacts on winds have not been studied. In January of 2012, a persistent, narrow band of cloud stretching 600-1,000 km was observed along the front of East China Sea (ECS). Numerical and analytical models show that the cloud was formed atop a recirculating cell induced by the front and, more generally, that ?-plumes of low and high pressures emanate and spread far from fronts. Consistent with the theory, observations show that in ECS at inter-annual time scales, strong fronts co-vary with on-shelf convergent wind, strong northeasterly monsoon, and alongshelf alignment of clouds with low clouds near the coast and higher clouds offshore. Our results suggest that shelf-sea fronts are potentially an important dynamic determinant of climate variability of East Asia.

Oey, L.-Y.; Chang, M.-C.; Huang, S.-M.; Lin, Y.-C.; Lee, M.-A.

2015-01-01

23

Winterization of peanut biodiesel to improve the cold flow properties.  

PubMed

Biodiesel is susceptible to start-up and performance problems, consistent with its chemical composition, when vehicles and fuel systems are subjected to cold temperatures. In this work, a comprehensive evaluation of the crystallization behavior of different biodiesels was performed by measuring the cold filter plugging point (CFPP), cloud point (CP) and pour point (PP). Results were related to differential scanning calorimetry (DSC) thermograms. Peanut methyl esters in particular led to the most unfavorable properties due to the presence of long-chain saturated compounds (arachidic or C20:0, behenic or C22:0, and lignoceric or C24:0 acid methyl esters) approaching 6 wt.%. The cold flow properties may be improved with different winterization techniques to eliminate some of these compounds. In this work, various techniques are tested, and the best technique is found to be crystallization filtration using methanol, which reduces the CFPP from 17 degrees C to -8 degrees C with a biodiesel loss of 8.93 wt.%. Moreover, the cake from filtration, enriched with long-chain saturated methyl esters, can be used as phase change material (PCM) for thermo-regulated materials. PMID:20547059

Pérez, Angel; Casas, Abraham; Fernández, Carmen María; Ramos, María Jesús; Rodríguez, Lourdes

2010-10-01

24

Influence of the Gulf Stream on the Barents Sea ice retreat and Eurasian coldness during early winter  

NASA Astrophysics Data System (ADS)

Abnormal sea-ice retreat over the Barents Sea during early winter has been considered a leading driver of recent midlatitude severe winters over Eurasia. However, causal relationships between such retreat and the atmospheric circulation anomalies remains uncertain. Using a reanalysis dataset, we found that poleward shift of a sea surface temperature front over the Gulf Stream likely induces warm southerly advection and consequent sea-ice decline over the Barents Sea sector, and a cold anomaly over Eurasia via planetary waves triggered over the Gulf Stream region. The above mechanism is supported by the steady atmospheric response to the diabatic heating anomalies over the Gulf Stream region obtained with a linear baroclinic model. The remote atmospheric response from the Gulf Stream would be amplified over the Barents Sea region via interacting with sea-ice anomaly, promoting the warm Arctic and cold Eurasian pattern.

Sato, Kazutoshi; Inoue, Jun; Watanabe, Masahiro

2014-08-01

25

Winter 2010 in Europe: A cold extreme in a warming climate  

NASA Astrophysics Data System (ADS)

The winter of 2009/2010 was characterized by record persistence of the negative phase of the North-Atlantic Oscillation (NAO) which caused several severe cold spells over Northern and Western Europe. This somehow unusual winter with respect to the most recent ones arose concurrently with public debate on climate change, during and after the Copenhagen climate negotiations. We show however that the cold European temperature anomaly of winter 2010 was (i) not extreme relative to winters of the past six decades, and (ii) warmer than expected from its record-breaking seasonal circulation indices such as NAO or blocking frequency. Daily flow-analogues of winter 2010, taken in past winters, were associated with much colder temperatures. The winter 2010 thus provides a consistent picture of a regional cold event mitigated by long-term climate warming.

Cattiaux, J.; Vautard, R.; Cassou, C.; Yiou, P.; Masson-Delmotte, V.; Codron, F.

2010-10-01

26

Habitat suitability index models: greater white-fronted goose (wintering). [Anser albifrons  

SciTech Connect

A review and synthesis of available information were used to develop models for indexing the potential suitability of agricultural and natural wetland habitats for wintering white-fronted geese (Anser albifrons). The model is scaled to produce indices of habitat suitability from 0 (unsuitable habitat) to 1.0 (optimal habitat) primarily for wintering habitat in southwest Louisiana and southwest Texas. Habitat suitability indices are designed for use with Habitat Evaluations Procedures previously developed by the US Fish and Wildlife Service.

Kaminski, R.M.

1986-07-01

27

Winter Habitat Preferences for Florida Manatees and Vulnerability to Cold  

PubMed Central

To survive cold winter periods most, if not all, Florida manatees rely on warm-water refuges in the southern two-thirds of the Florida peninsula. Most refuges are either warm-water discharges from power plant and natural springs, or passive thermal basins that temporarily trap relatively warm water for a week or more. Strong fidelity to one or more refuges has created four relatively discrete Florida manatee subpopulations. Using statewide winter counts of manatees from 1999 to 2011, we provide the first attempt to quantify the proportion of animals using the three principal refuge types (power plants, springs, and passive thermal basins) statewide and for each subpopulation. Statewide across all years, 48.5% of all manatees were counted at power plant outfalls, 17.5% at natural springs, and 34.9 % at passive thermal basins or sites with no known warm-water features. Atlantic Coast and Southwest Florida subpopulations comprised 82.2% of all manatees counted (45.6% and 36.6%, respectively) with each subpopulation relying principally on power plants (66.6% and 47.4%, respectively). The upper St. Johns River and Northwest Florida subpopulations comprised 17.8% of all manatees counted with almost all animals relying entirely on springs (99.2% and 88.6% of those subpopulations, respectively). A record high count of 5,076 manatees in January 2010 revealed minimum sizes for the four subpopulations of: 230 manatees in the upper St. Johns River; 2,548 on the Atlantic Coast; 645 in Northwest Florida; and 1,774 in Southwest Florida. Based on a comparison of carcass recovery locations for 713 manatees killed by cold stress between 1999 and 2011 and the distribution of known refuges, it appears that springs offer manatees the best protection against cold stress. Long-term survival of Florida manatees will require improved efforts to enhance and protect manatee access to and use of warm-water springs as power plant outfalls are shut down. PMID:23527063

Laist, David W.; Taylor, Cynthia; Reynolds, John E.

2013-01-01

28

Winter habitat preferences for Florida manatees and vulnerability to cold.  

PubMed

To survive cold winter periods most, if not all, Florida manatees rely on warm-water refuges in the southern two-thirds of the Florida peninsula. Most refuges are either warm-water discharges from power plant and natural springs, or passive thermal basins that temporarily trap relatively warm water for a week or more. Strong fidelity to one or more refuges has created four relatively discrete Florida manatee subpopulations. Using statewide winter counts of manatees from 1999 to 2011, we provide the first attempt to quantify the proportion of animals using the three principal refuge types (power plants, springs, and passive thermal basins) statewide and for each subpopulation. Statewide across all years, 48.5% of all manatees were counted at power plant outfalls, 17.5% at natural springs, and 34.9 % at passive thermal basins or sites with no known warm-water features. Atlantic Coast and Southwest Florida subpopulations comprised 82.2% of all manatees counted (45.6% and 36.6%, respectively) with each subpopulation relying principally on power plants (66.6% and 47.4%, respectively). The upper St. Johns River and Northwest Florida subpopulations comprised 17.8% of all manatees counted with almost all animals relying entirely on springs (99.2% and 88.6% of those subpopulations, respectively). A record high count of 5,076 manatees in January 2010 revealed minimum sizes for the four subpopulations of: 230 manatees in the upper St. Johns River; 2,548 on the Atlantic Coast; 645 in Northwest Florida; and 1,774 in Southwest Florida. Based on a comparison of carcass recovery locations for 713 manatees killed by cold stress between 1999 and 2011 and the distribution of known refuges, it appears that springs offer manatees the best protection against cold stress. Long-term survival of Florida manatees will require improved efforts to enhance and protect manatee access to and use of warm-water springs as power plant outfalls are shut down. PMID:23527063

Laist, David W; Taylor, Cynthia; Reynolds, John E

2013-01-01

29

Wintering site interchange amongst Greenland White-fronted Geese Anser albifrons flavirostris captured at Wexford Slobs, Ireland  

Microsoft Academic Search

The maximum count of Greenland White-fronted Geese wintering at Wexford, south-east Ireland (where over a third of the population winters) increased from 7910 in 1984\\/85 to 9530 in 1989\\/90. Although the population tends to be highly site-loyal on the wintering grounds, 14% of 700 marked geese seen in two consecutive winters changed site. Counts elsewhere in the wintering range and

S. M. Warren; A. J. Walsh; O. J. Merne; H. J. Wilson; A. D. Fox

1992-01-01

30

Social perceptions versus meteorological observations of snow and winter along the Front Range  

NASA Astrophysics Data System (ADS)

This research aims to increase understanding of Front Range residents' perceptions of snow, winter and hydrologic events. This study also investigates how an individual's characteristics may shape perceptions of winter weather and climate. A survey was administered to determine if perceptions of previous winters align with observed meteorological data. The survey also investigated how individual characteristics influence perceptions of snow and winter weather. The survey was conducted primarily along the Front Range area of the state of Colorado in the United States of America. This is a highly populated semi-arid region that acts as an interface between the agricultural plains to the east that extend to the Mississippi River and the Rocky Mountains to the west. The climate is continental, and while many people recreate in the snowy areas of the mountains, most live where annual snowfall amounts are low. Precipitation, temperature, and wind speed datasets from selected weather stations were analyzed to determine correct survey responses. Survey analysis revealed that perceptions of previous winters do not necessarily align with observed meteorological data. The mean percentage of correct responses to all survey questions was 36.8%. Further analysis revealed that some individual characteristics (e.g. winter recreation, source of winter weather information) did influence correct responses to survey questions.

Milligan, William James, IV

31

Know before you go. Don't get left out in the cold. Prepare your vehicle for winter weather.  

E-print Network

Know before you go. Don't get left out in the cold. Prepare your vehicle for winter weather. Do you drive during winter? Winter weather is hard on your vehicle and its engine. Here are some tips to help tire air pressure frequently, as it decreases in cold weather. 2. Get your car winter ready

Kavanagh, Karen L.

32

Microstructure of cold fronts and implications as to their detection by radar  

E-print Network

MICROSTRUCTURE OF COLD FRONTS AND IMPLICATIONS AS TO THEIR DETECTION BY RADAR A Thesis by GRANT CLIFFORD AUFDERHAAR Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE August 1972 Major Subject: Meteorology MICROSTRUCTURE 01' COLD FRONTS AViD IMPLICATIONS AS TO TIIEIR DETECTIOVi BY RADAR A Thesis by GRANT CLIFI'ORD AUFDERIIAAR Approved as to style and content by: (Chairman of Committee) (Head of Depart...

Aufderhaar, Grant Clifford

1972-01-01

33

Finescale Vertical Structure of a Cold Front as Revealed by an Airborne Doppler Radar  

Microsoft Academic Search

In the afternoon of 24 May 2002, a well-defined and frontogenetic cold front moved through the Texas panhandle. Detailed observations from a series of platforms were collected near the triple point between this cold front and a dryline boundary. This paper primarily uses reflectivity and Doppler velocity data from an airborne 95-GHz radar, as well as flight-level thermodynamic data, to

Bart Geerts; Rick Damiani; Samuel Haimov

2006-01-01

34

Physical changes within a large tropical hydroelectric reservoir induced by wintertime cold front activity  

NASA Astrophysics Data System (ADS)

We investigated the influence of wintertime cold front activity on the physical processes within a large tropical reservoir located in Brazil. The period chosen for this study consisted of 49 days between 28 April 2010 and 15 July 2010. This period was defined based on information from the Brazilian Center for Weather Forecasting and Climate Studies (CPTEC), data collected in situ and the interpretation of remotely sensed images. To better understand the governing processes that drive changes in the heat balance, differential cooling and mixing dynamics, a simulation was performed that utilized a three-dimensional hydrodynamic model enforced with in situ and remote sensing data. The results showed that during a cold front passage over the reservoir, the sensible and latent heat fluxes were enhanced by approximately 77 and 16%, respectively. The reservoir's daily averaged heat loss was up to 167% higher on the days with cold front activity than on the days without activity. The cold front passage also intensified the differential cooling process; in some cases the difference between the water temperature of the littoral and pelagic zones reached up to 8 °C. The occurrence of cold front passages impacted the diurnal mixed layer (DML), by increasing the turbulent energy input (∼54%) and the DML depth (∼41%). Our results indicate that the cold front events are one of the main meteorological disturbances driving the physical processes within hydroelectric reservoirs located in tropical South America during the wintertime. Hence, cold front activity over these aquatic systems has several implications for water quality and reservoir management in Brazil.

Curtarelli, M. P.; Alcântara, E. H.; Rennó, C. D.; Stech, J. L.

2014-08-01

35

Humidity Control Systems for Civil Buildings in Hot Summer and Cold Winter Zone in China  

E-print Network

controlled unit to dry and cool outdoor air. Key words: hot summer and cold winter zone; civil buildings; humidity control; air-conditioning system; ventilation mode 1 INTRODUCTION The Yangtze River basin, its special geographic location causes...

Yu, X.

2006-01-01

36

Magnetized thermal conduction fronts. [between hot and cold astrophysical plasma  

NASA Technical Reports Server (NTRS)

The evolution of planar thermal conduction fronts in the presence of a dynamically weak, but otherwise self-consistent, magnetic field is considered. The field is assumed to be connected and untangled. In the diffusion limit for the thermal conductivity, these fronts exhibit self-similar behavior, even in the presence of a field. The role of the field is restricted to channeling the heat flux along its lines of force, and it enters into the problem as a dimensionless angle variable. 'Combing' (or opening) of insulating field lines by the evaporative flow is explicitly demonstrated. Unless the field is nearly perpendicular to the front normal in the hot gas, insulating effects are not profound. Self-similarity breaks down if the front becomes saturated, and under certain conditions magnetized saturated conduction fronts cannot propagate: the solution characteristics of the wave equation form caustics. The physical resolution is the advent of two-fluid (nonlocal) heating. Such Coulomb-heated fronts are expected to be relatively rare in typical astrophysical systems. The large-scale effects of a magnetic field on cloud evaporation in the interstellar medium are briefly discussed, and it is suggested that these fields preclude the presence of time-independent evaporative solutions. Thermal interfaces may then continue to evolve until radiative cooling halts their development; large tracts of warm 10,000 K gas may result.

Balbus, S. A.

1986-01-01

37

Cold front induced changes on the Florida panhandle shelf during October 2008  

NASA Astrophysics Data System (ADS)

A significant step transition between seasonally stratified and destratified hydrographic conditions occurred during an October 2008 cruise to the Florida Panhandle Shelf along a cross-shelf transect that was sampled before and after a cold front passed through the area. Meteorological measurements from nearby ocean and land-based stations characterized the event. Cross-shelf continuous Acrobat profiles and discrete CTD stations characterized water column hydrographic patterns, while mid-shelf multicorer and box corer samples characterized sediment texture and nutrients. Water samples collected from selected depths biased toward the sediment interface were analyzed for nutrient content and phytoplankton community composition. Pre-front, the cross-shelf water column exhibited vertical stratification with complex temperature and salinity patterns. A prominent near-bottom chlorophyll a maximum of ˜1.5 ?g L-1 between the 25-35 m isobaths occurred with the 1% light level at ˜18 m depth and a near-bottom nitrate+nitrite (NO3-+NO2-) maximum >3 ?M between the 30-40 m isobaths. HPLC-determined phytoplankton community composition in the near-bottom chlorophyll a maximum consisted of gyroxanthin-containing dinoflagellates (Karenia brevis) and less abundant diatoms, both verified by FlowCAM analysis, mixed with detectable cryptophytes and chlorophytes. Sediment trends based on limited core replicates suggested the sediments were a potential source of nutrients to near-bottom populations of K. brevis and that shell hash could provide abundant pore space for K. brevis incursions. Between the 40-50 m isobaths, diatoms, cryptophytes and chlorophytes dominated near-bottom, gyroxanthin-containing dinoflagellates and prasinophytes occurred throughout the water column, and cyanophytes dominated near-surface. Post-front, the cross-shelf water column exhibited destratification with temperature and salinity increasing offshore. A chlorophyll a maximum of ˜0.75 ?g Chl a L-1 left the sediment between 25-35 m isobaths and extended offshore especially in the lower water column with the 1% light level at ˜15 m depth and NO3-+NO2- concentrations ˜2 ?M to the 60 m isobath. HPLC-determined phytoplankton community composition of the offshore plume retained the signature of gyroxanthin-containing dinoflagellates and chlorophytes. Between the 30-50 m isobaths, prasinophytes increased in the lower water column, while cyanophytes increased at all depths across the shelf. The observed step transition from stratification to destratification on the Florida Panhandle Shelf contributed to altered phytoplankton community patterns in response to predominant downwelling favorable winds. Pre-front, K. brevis cells were broadly distributed cross-shelf, but concentrated near-bottom between the 25-35 m isobaths and staged for prolific bloom seeding in response to the upwelling favorable west winds more typical of spring-summer. Post-front, K. brevis cells were mixed throughout the mid-shelf water column and were staged for diffuse bloom seeding in response to either the downwelling or upwelling favorable winds occurring fall-winter. Cyanophytes located predominantly near-surface offshore pre-front, were ubiquitous cross-shelf and more closely associated with K. brevis post-front.

Kamykowski, D.; Pridgen, K. Grabowski; Morrison, J. M.; McCulloch, A. A.; Nyadjro, E. S.; Thomas, C. A.; Sinclair, G. A.

2013-02-01

38

Cold truths: how winter drives responses of terrestrial organisms to climate change.  

PubMed

Winter is a key driver of individual performance, community composition, and ecological interactions in terrestrial habitats. Although climate change research tends to focus on performance in the growing season, climate change is also modifying winter conditions rapidly. Changes to winter temperatures, the variability of winter conditions, and winter snow cover can interact to induce cold injury, alter energy and water balance, advance or retard phenology, and modify community interactions. Species vary in their susceptibility to these winter drivers, hampering efforts to predict biological responses to climate change. Existing frameworks for predicting the impacts of climate change do not incorporate the complexity of organismal responses to winter. Here, we synthesise organismal responses to winter climate change, and use this synthesis to build a framework to predict exposure and sensitivity to negative impacts. This framework can be used to estimate the vulnerability of species to winter climate change. We describe the importance of relationships between winter conditions and performance during the growing season in determining fitness, and demonstrate how summer and winter processes are linked. Incorporating winter into current models will require concerted effort from theoreticians and empiricists, and the expansion of current growing-season studies to incorporate winter. PMID:24720862

Williams, Caroline M; Henry, Hugh A L; Sinclair, Brent J

2015-02-01

39

Increase in Indoleacetic Acid Oxidase Activity of Winter Wheat by Cold Treatment and Gibberellic Acid 1  

PubMed Central

The activity of indoleacetic acid oxidase increased 10-fold during 40 days of cold treatment of winter wheat seedlings. Puromycin and 6-methyl purine inhibited indoleacetic acid oxidase development in the cold. Addition of gibberellic acid stimulated indoleacetic acid oxidase development during germination at room temperature and during cold treatment. Amo-1618 inhibited indoleacetic acid oxidase development before and during cold treatment. Indoleacetic acid treatment increased indoleacetic acid oxidase activity during germination at room temperature while no significant effect on activity was observed during cold treatment. PMID:16657327

Bolduc, Reginald J.; Cherry, Joe H.; Blair, Byron O.

1970-01-01

40

Chitinase Genes Responsive to Cold Encode Antifreeze Proteins in Winter Cereals1  

PubMed Central

Antifreeze proteins similar to two different chitinases accumulate during cold acclimation in winter rye (Secale cereale). To determine whether these cold-responsive chitinases require post-translational modification to bind to ice, cDNAs coding for two different full-length chitinases were isolated from a cDNA library produced from cold-acclimated winter rye leaves. CHT9 is a 1,193-bp clone that encodes a 31.7-kD class I chitinase and CHT46 is a 998-bp clone that codes for a 24.8-kD class II chitinase. Chitinase-antifreeze proteins purified from the plant were similar in mass to the predicted mature products of CHT9 and CHT46, thus indicating that there was little chemical modification of the amino acid sequences in planta. To confirm these results, the mature sequences of CHT9 and CHT46 were expressed in Escherichia coli and the products of both cDNAs modified the growth of ice. Transcripts of both genes accumulated late in cold acclimation in winter rye. Southern analysis of winter rye genomic DNA indicated the presence of a small gene family homologous to CHT46. In hexaploid wheat, CHT46 homologs mapped to the homeologous group 1 chromosomes and were expressed in response to cold and drought. We conclude that two novel cold-responsive genes encoding chitinases with ice-binding activity may have arisen in winter rye and other cereals through gene duplication. PMID:11080301

Yeh, Sansun; Moffatt, Barbara A.; Griffith, Marilyn; Xiong, Fei; Yang, Daniel S.C.; Wiseman, Steven B.; Sarhan, Fathey; Danyluk, Jean; Xue, Yi Qi; Hew, Choy L.; Doherty-Kirby, Amanda; Lajoie, Gilles

2000-01-01

41

Eddy conductivity in and near dry cold fronts in the layer, 70 to 1270 feet  

E-print Network

EDDY CONDUCTIVITY IN AND NEAR DRY COLD FRONTS IN THE LAYER, 70 TO 1270 FEET A Thesis By EDWARD FRANCIS CONLAN Captain, USAF Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE January 1965 Major Subject: METEOROLOGY EDDY CONDUCTIVITY IN AND NEAR DRY COLD FRONTS IN THE LAYER) 70 TO 1270 FEET A Thesis By EDWARD FRANCIS CONLAN Captain, USAF Approved as to style and content by: i J 8~. . c6~h arrmanf o...

Conlan, Edward Francis

1965-01-01

42

Chandra Estimate of the Magnetic Field Strength near the Cold Front in A3667  

NASA Astrophysics Data System (ADS)

We use the Chandra observation of the cold front in the intracluster gas of A3667 to estimate the magnetic field strength near the front. The front is seen in the Chandra data as a sharp discontinuity in the gas density that delineates a large body of dense cool gas moving with near-sonic velocity through the less dense, hotter gas. Without a magnetic field, the front should be quickly disturbed by the Kelvin-Helmholtz instability arising from tangential motion of gas layers. However, the Chandra image shows that the front is stable within a +/-30° sector in the direction of the cloud motion, beyond which it gradually disappears. We suggest that the Kelvin-Helmholtz instability within the +/-30° sector is suppressed by the surface tension of the magnetic field whose field lines are parallel to the front. The required field strength is B~10 ?G. The magnetic field near the front is expected to be stronger and to have a very different structure compared with the bulk of the intergalactic medium because the field lines are stretched by the tangential gas motions. Such a magnetic configuration, once formed, would effectively stop the plasma diffusion and heat conduction across the front and may inhibit gas mixing during the subcluster merger. We note that even the increased magnetic field near the front contributes only 10%-20% to the total gas pressure, and therefore magnetic pressure is unimportant for hydrostatic cluster mass estimates.

Vikhlinin, A.; Markevitch, M.; Murray, S. S.

2001-03-01

43

The impact of winter cold weather on acute myocardial infarctions in Portugal.  

PubMed

Mortality due to cardiovascular diseases shows a seasonal trend that can be associated with cold weather. Portugal is the European country with the highest excess winter mortality, but nevertheless, the relationship between cold weather and health is yet to be assessed. The main aim of this study is to identify the contribution of cold weather to cardiovascular diseases within Portugal. Poisson regression analysis based on generalized additive models was applied to estimate the influence of a human-biometeorological index (PET) on daily hospitalizations for myocardial infarction. The main results revealed a negative effect of cold weather on acute myocardial infarctions in Portugal. For every degree fall in PET during winter, there was an increase of up to 2.2% (95% CI = 0.9%; 3.3%) in daily hospital admissions. This paper shows the need for public policies that will help minimize or, indeed, prevent exposure to cold. PMID:23410618

Vasconcelos, João; Freire, Elisabete; Almendra, Ricardo; Silva, Giovani L; Santana, Paula

2013-12-01

44

Ready.Gov for Kids: Winter Storms/Extreme Cold  

MedlinePLUS

... storms bring dangerously low temperatures and, sometimes, strong winds, icing, sleet, and freezing rain. One of the main concerns is that winter weather can knock out heat, power, and communication, sometimes for days at a time. ...

45

Effects of cold front passage on turbulent fluxes over a large inland water  

NASA Astrophysics Data System (ADS)

Turbulent fluxes of sensible and latent heat over a large inland water in southern USA were measured using the eddy covariance method through the year of 2008. In addition, net radiation, air temperatures and relative humidity, and water temperature in different depths were also measured. The specific objective of this study is to examine effects of a cold front passage on the surface energy fluxes. For the typical cold front event selected from April 11 to 14, air temperature decreased by 16°C, while surface temperature only dropped 6°C. Atmospheric vapor pressure decreased by 1.6 kPa, while that in the water-air interface dropped 0.7 kPa. The behavior difference in the water-air interface was caused by the passage of cold, dry air masses immediately behind the cold front. During the cold front event, sensible heat and latent heat flux increased by 171 W m-2 and 284 W m-2, respectively. Linear aggression analysis showed that the sensible heat flux was proportional to the product of wind speed and the temperature gradient of water-air interface, with a correlation coefficient of 0.95. Latent heat flux was proportional to the product of wind speed and vapor pressure difference between the water surface and overlaying atmosphere, with a correlation coefficient of 0.81. Also, the correlations between both fluxes and the wind speed were weak. This result indicated that the strong wind associated with the cold front event contributed to the turbulent mixing, which indirectly enhanced surface energy exchange between the water surface and the atmosphere. The relationship between the water heat storage energy and turbulent fluxes was also examined.

Zhang, Q.; Liu, H.

2011-12-01

46

Cold War: Flora's Undercover Agents. A Campus Winter Field Trip to Illustrate That Plants Do Indeed Thermoregulate.  

ERIC Educational Resources Information Center

Proposes using a winter field trip to explore how various plants on a campus thermoregulate. Describes techniques for determining the location of cold stresses in plants and how plants manage to deal with the cold stresses. (DDR)

DeGolier, Teresa

2002-01-01

47

MERGING COLD FRONTS IN THE GALAXY PAIR NGC 7619 AND NGC 7626  

Microsoft Academic Search

We present results from Chandra observations of the galaxy pair NGC 7619 and NGC 7626, the two dominant members of the Pegasus group. The X-ray images show a brightness edge associated with each galaxy, which we identify as merger cold fronts. The edges are sharp, and the axes of symmetry of the edges are roughly antiparallel, suggesting that these galaxies

S. W. Randall; C. Jones; R. Kraft; W. R. Forman; E. OSullivan

2009-01-01

48

Merging Cold Fronts in the Galaxy Pair NGC 7619 and NGC 7626  

Microsoft Academic Search

We present results from Chandra observations of the galaxy pair NGC 7619 and NGC 7626, the two dominant members of the Pegasus group. The X-ray images show a brightness edge associated with each galaxy, which we identify as merger cold fronts. The edges are sharp, and the axes of symmetry of the edges are roughly antiparallel, suggesting that these galaxies

S. W. Randall; C. Jones; R. Kraft; W. R. Forman; E. O'Sullivan

2009-01-01

49

Export of Asian pollution during two cold front episodes of the TRACE-P experiment  

E-print Network

Export of Asian pollution during two cold front episodes of the TRACE-P experiment C. Mari how these cyclonic systems have impacted the export of pollution out of the Asian continent. We of pollution are met during flight 13 (i.e., the occurrences of the warm conveyor belt near the source regions

Palmer, Paul

50

Unusually cold and dry winters increase mortality in Australia.  

PubMed

Seasonal patterns in mortality have been recognised for decades, with a marked excess of deaths in winter, yet our understanding of the causes of this phenomenon is not yet complete. Research has shown that low and high temperatures are associated with increased mortality independently of season; however, the impact of unseasonal weather on mortality has been less studied. In this study, we aimed to determine if unseasonal patterns in weather were associated with unseasonal patterns in mortality. We obtained daily temperature, humidity and mortality data from 1988 to 2009 for five major Australian cities with a range of climates. We split the seasonal patterns in temperature, humidity and mortality into their stationary and non-stationary parts. A stationary seasonal pattern is consistent from year-to-year, and a non-stationary pattern varies from year-to-year. We used Poisson regression to investigate associations between unseasonal weather and an unusual number of deaths. We found that deaths rates in Australia were 20-30% higher in winter than summer. The seasonal pattern of mortality was non-stationary, with much larger peaks in some winters. Winters that were colder or drier than a typical winter had significantly increased death risks in most cities. Conversely summers that were warmer or more humid than average showed no increase in death risks. Better understanding the occurrence and cause of seasonal variations in mortality will help with disease prevention and save lives. PMID:25460613

Huang, Cunrui; Chu, Cordia; Wang, Xiaoming; Barnett, Adrian G

2015-01-01

51

The Interruption of Alpine Foehn by a Cold Front. Part I: Observations  

NASA Astrophysics Data System (ADS)

The propagation of a cold front and its interaction with foehn winds is investigated in an Alpine valley, based on observations collected during the field campaign of the Mesoscale Alpine Programme (MAP) on 6 November 1999. The key instrument of this study is a Doppler lidar that had been operated in the Wipp Valley (Austria). The cold front approached the European Alps from the northwest, became distorted at the mountain barrier and entered the east-west aligned Inn Valley near the town of Innsbruck primarily via two passes. It continued to propagate towards Innsbruck from both valley directions as two separate fronts that eventually collided east of Innsbruck after part of the cold air had entered the adjacent north-south aligned Wipp Valley. In the Inn and Wipp Valley, the front caused the interruption of foehn winds. A synthesis of Doppler lidar measurements with conventional meteorological data, including automatic weather stations and radiosondes, leads to the conclusion that the cold front in the Wipp Valley was an atmospheric density current characterized by an elevated head, a front-relative feeder flow and a typical propagation speed of 7 m s-1. The foehn flow on top of the density current caused strong wind shear and triggered shear-flow instability that led to the formation of a turbulent wake behind the head. As the density current propagated towards the Brenner Pass, it slowed down. The shape of the frontal surface varied in time. Its inclination of about 10"-20" is steeper than previously reported for the Inn Valley but is consistent with other observations of atmospheric density currents. In a follow-up presentation (part 2) this observational study is complemented by high-resolution numerical simulations.

Gohm, A.; Mayr, G. J.; Darby, L. S.; Banta, R. M.

2010-09-01

52

Geographic variation in migration chronology and winter distribution of midcontinent greater white-fronted geese  

USGS Publications Warehouse

We evaluated spatial and temporal differences in migratory behavior among different breeding groups of midcontinent greater white-fronted geese (Anser albifrons) using band-recovery data and observations of neck collared geese during migration and winter. Birds from different breeding areas were initially delineated by geographic distance into 6 banding reference areas (BRAs): 1) interior Alaska, 2) North Slope of Alaska, 3) western Northwest Territories (NWT), 4) western Nunavut, 5) central Nunavut, and 6) eastern Nunavut. The banding groups also differed by breeding habitat, with geese from interior Alaska nesting in the boreal forest (taiga), and all other groups breeding in tundra habitats. Geese from interior Alaska migrated earlier during autumn, and were more likely to winter farther south (in Mexico) than geese from other breeding areas. Geese banded in central and eastern Nunavut (Queen Maud Gulf and Inglis River) wintered farther east (in Louisiana) than geese from other breeding areas. Small-scale (within-state) geographic segregation of wintering flocks was evidenced by the recent (post-1990) nearly exclusive use of a new wintering area in north central Texas by geese from interior Alaska. Segregation among BRAs was also apparent in Mexico, where taiga geese were found predominantly in the central Highlands (states of Zacatecas and Durango), whereas tundra geese mostly used states along the Gulf Coast (primarily Tamaulipas). Interior Alaska birds initiated spring migration earlier than geese from other areas, and were more likely than others to stop in the Rainwater Basin of Nebraska, a region where cholera outbreaks periodically kill thousands of geese. Geese from interior Alaska were the first to arrive at spring staging areas in prairie Canada where BRAs exhibited spatial delineation (a longitudinal cline) in relation to breeding areas. Our results show significant geographic and temporal variation among taiga and tundra breeding cohorts during autumn, winter, and spring. Temporal and spatial differences in migratory behavior may allow management practices that accommodate potential demographic differences between taiga and tundra populations.

Ely, Craig R.; Nieman, Daniel J.; Alisauskas, Ray T.; Schmutz, Joel A.; Hines, James E.

2013-01-01

53

Orographic low-level clouds of Southeast Asia during the cold surges of the winter monsoon  

NASA Astrophysics Data System (ADS)

This study is an examination of low clouds over Southeast Asia during northern fall and winter using albedo values derived from visible images, cloud-top temperatures from infrared radiation images from the Multi-functional Transport Satellite 1 (MTSAT-1), and rainfall-top height (storm height) from precipitation radar (PR) on the Tropical Rainfall Measuring Mission (TRMM) satellites. To understand the cloud and precipitation activities associated with the winter monsoon cold surges along the eastern coast of the Indochina Peninsula, atmospheric circulation data from the Japanese 25-year reanalysis (JRA-25) were used. The results showed that low clouds were frequently observed in December, January, and February. In October and November, rainfall activity was relatively high, whereas, in northern winter, it was low, although the winter monsoon northeasterly was strong in both cases. The cloud-top height and storm height decreased with the seasonal march from northern fall to winter. Also examined in this study were the temporal variations in cloud activity on shorter time scales than those of the seasonal march. Concurrent with the cold surges along the eastern coast of the Eurasia, clouds varied on synoptic and intraseasonal time scales. The timing of low-cloud formation corresponded to the beginning of the cold surges. However, the low clouds along the eastern coast of the Indochina Peninsula may remain during the weakening phase of the cold surges.

Takahashi, Hiroshi G.

2013-09-01

54

Cold fronts in the Colombian Caribbean Sea and their relationship to extreme wave events  

NASA Astrophysics Data System (ADS)

Extreme ocean waves in the Caribbean Sea are commonly related to the effects of storms and hurricanes during the months of June through November. The collapse of 200 m of the Puerto Colombia pier in March 2009 revealed the effects of meteorological phenomena other than storms and hurricanes that may be influencing the extreme wave regime in the Colombian Caribbean. The marked seasonality of these atmospheric fronts was established by analyzing the meteorological-marine reports of the Instituto de Hidrología, Meteorología y Estudios Ambientales of Colombia (IDEAM, based on its initials in Spanish) and the Centro de Investigación en Oceanografía y Meteorología of Colombia (CIOH, based on its initials in Spanish) during the last 16 yr. The highest number of cold fronts was observed during the months of January, February, and March, with 6 fronts occurring per year. An annual trend was observed and the highest number of fronts occurred in 2010 (20 in total); moreover, an annual strong relationship between the maximum average wave values and the cold fronts in the central zone of the Colombian Caribbean during the first three months of the year was established. In addition, the maximum values of the significant height produced by the passage of cold fronts during the last 16 yr were identified. Although the Colombian Caribbean has been affected by storms and hurricanes in the past, this research allows us to conclude that there is a strong relationship between cold fronts and the largest waves in the Colombian Caribbean during the last 16 yr, which have caused damage to coastal infrastructure. We verified that the passage of a cold front corresponded to the most significant extreme wave event of the last two decades in the Colombian Caribbean, which caused the structural collapse of the Puerto Colombia pier, located near the city of Barranquilla, between 5 and 10 March 2009. This information is invaluable when evaluating average and extreme wave regimes for the purpose of informing the design of structures in this region of the Caribbean.

Ortiz-Royero, J. C.; Otero, L. J.; Restrepo, J. C.; Ruiz, J.; Cadena, M.

2013-11-01

55

The Interruption of Alpine Foehn by a Cold Front. Part II: Numerical Simulations  

NASA Astrophysics Data System (ADS)

In this work the interaction of Alpine foehn winds with a cold front is investigated. Despite the wealth of studies on south foehn in the region of Innsbruck during the last century not much is known about the dynamics of foehn breakdown. In most cases, the interruption of foehn is connected with a cold front, which approaches the Alps from northerly or northwesterly directions. The resulting change of warm and dry southerly winds to a cold and moist airmass may occur within less than an hour. The objective of this study is to receive a better understanding of the dynamical processes connected with the collision of two airflows from opposing directions in an Alpine valley by means of numerical simulations conducted with the Weather Research and Forecasting (WRF) Model, Version 3.1. For this purpose a foehn event at the Special Observing Period (SOP) of the Mesoscale Alpine Programme (MAP) has been chosen. On 6 November 1999 a cold front impinged on the Alps and caused the breakdown of the foehn flow. The investigations are mainly focused on the Austrian Inn- and Wipp Valley, which has been one of the target areas during the MAP SOP. The results from the mesoscale model are compaired against the large available observational data set, including surface station, radiosonde and lidar measurements. Nested model runs provide the ability to investigate a wide range of temporal and spatial scales. The model is able to capture the blocking of moist air south of the Alps during foehn and the deformation of the cold front by the mountain range north of the Alps. To quantitatively describe the exchange of air masses in a given box near Innsbruck a mass budget calculation has been accomplished. The most prominent feature is a sudden increase of the inflow from the west during the cold front passage. The fine-scale structure of the cold front, which shows the nature of a density current, is determined with an additional one-way nested high-resolution simulation in the Wipp Valley. Futhermore, the sensitivity of the model results on the initial and boundary conditions, which are based on different ECMWF analysis products, is studied. Apart from these tests, it is shown, that the quality of the numerical simulations strongly depends on the type of boundary-layer parametrization used in the model.

Dautz, E.; Gohm, A.

2010-09-01

56

Concurrent variation between the East Asian subtropical jet and polar front jet during persistent snowstorm period in 2008 winter over southern China  

NASA Astrophysics Data System (ADS)

The concurrent variation features between the East Asian subtropical jet and polar front jet were investigated during persistent snowstorm period in 2007/2008 winter over southern China. The East Asian subtropical jet was divided into two parts: (1) the plateau jet, located along the southern side of the Tibetan Plateau, and (2) the ocean jet, situated at the southeastern Japan Island. The concurrent intensity variation among the polar front jet, plateau jet, and ocean jet and the associated atmospheric anomalous signals were examined. A possible mechanism for concurrent variation among the three jets was also investigated from a perspective of synoptic-scale transient eddy activities (STEA). The enhanced plateau jet was simultaneously correlated with the weakened polar front jet, while the variation of the ocean jet lagged the variation of the plateau jet (polar front jet) about 5 days. The concurrent variation between the plateau jet and the polar front jet acted as an important bridge that linked the snowstorm to the atmospheric anomalous signals associated with the cold and warm air activities. Due to the opposite trends of STEA variation over the southern and northern sides of the Tibetan Plateau, the plateau jet and the polar front jet exhibited a significant concurrent variation feature. The STEA anomalies over the plateau jet and polar front jet regions propagated downstream to the East Asian coast as a wave train along the southern and northern sides of the Tibetan Plateau, respectively, resulting in a 5 day lag variation relationship between the ocean jet and the plateau jet (polar front jet).

Liao, Zhijie; Zhang, Yaocun

2013-06-01

57

A cold-regulated nucleic acid-binding protein of winter wheat shares a domain with bacterial cold shock proteins.  

PubMed

The molecular mechanisms of cold acclimation are still largely unknown; however, it has been established that overwintering plants such as winter wheat increases freeze tolerance during cold treatments. In prokaryotes, cold shock proteins are induced by temperature downshifts and have been proposed to function as RNA chaperones. A wheat cDNA encoding a putative nucleic acid-binding protein, WCSP1, was isolated and found to be homologous to the predominant CspA of Escherichia coli. The putative WCSP1 protein contains a three-domain structure consisting of an N-terminal cold shock domain with two internal conserved consensus RNA binding domains and an internal glycine-rich region, which is interspersed with three C-terminal CX(2)CX(4)HX(4)C (CCHC) zinc fingers. Each domain has been described independently within several nucleotide-binding proteins. Northern and Western blot analyses showed that WCSP1 mRNA and protein levels steadily increased during cold acclimation, respectively. WCSP1 induction was cold-specific because neither abscisic acid treatment, drought, salinity, nor heat stress induced WCSP1 expression. Nucleotide binding assays determined that WCSP1 binds ssDNA, dsDNA, and RNA homopolymers. The capacity to bind dsDNA was nearly eliminated in a mutant protein lacking C-terminal zinc fingers. Structural and expression similarities to E. coli CspA suggest that WCSP1 may be involved in gene regulation during cold acclimation. PMID:12122010

Karlson, Dale; Nakaminami, Kentaro; Toyomasu, Tomonobu; Imai, Ryozo

2002-09-20

58

Event duration (days) European cold winters and persistence of blocking  

E-print Network

of MAX(18-T2M;0). (2) Similar but for Effective Temperature, defined as TEFF=T2M-(2/3)U10M. (3-index correlates reasonably well with cold-indices like D(T2M) and D(TEFF), but there are outliers (e.g. 1991

de Vries, Hylke

59

Excess Winter Mortality and Cold Temperatures in a Subtropical City, Guangzhou, China  

PubMed Central

Background A significant increase in mortality was observed during cold winters in many temperate regions. However, there is a lack of evidence from tropical and subtropical regions, and the influence of ambient temperatures on seasonal variation of mortality was not well documented. Methods This study included 213,737 registered deaths from January 2003 to December 2011 in Guangzhou, a subtropical city in Southern China. Excess winter mortality was calculated by the excess percentage of monthly mortality in winters over that of non-winter months. A generalized linear model with a quasi-Poisson distribution was applied to analyze the association between monthly mean temperature and mortality, after controlling for other meteorological measures and air pollution. Results The mortality rate in the winter was 26% higher than the average rate in other seasons. On average, there were 1,848 excess winter deaths annually, with around half (52%) from cardiovascular diseases and a quarter (24%) from respiratory diseases. Excess winter mortality was higher in the elderly, females and those with low education level than the young, males and those with high education level, respectively. A much larger winter increase was observed in out-of-hospital mortality compared to in-hospital mortality (45% vs. 17%). We found a significant negative correlation of annual excess winter mortality with average winter temperature (rs=-0.738, P=0.037), but not with air pollution levels. A 1 °C decrease in monthly mean temperature was associated with an increase of 1.38% (95%CI:0.34%-2.40%) and 0.88% (95%CI:0.11%-1.64%) in monthly mortality at lags of 0-1 month, respectively. Conclusion Similar to temperate regions, a subtropical city Guangzhou showed a clear seasonal pattern in mortality, with a sharper spike in winter. Our results highlight the role of cold temperature on the winter mortality even in warm climate. Precautionary measures should be strengthened to mitigate cold-related mortality for people living in warm climate. PMID:24116214

Yang, Jun; Chau, Patsy Yuen-Kwan; Yang, Lin; Chen, Ping-Yan; Wong, Chit-Ming

2013-01-01

60

EVALUATON OF MID-WINTER COLD HARDINESS AMONG 25 RABBITEYE BLUEBERRY (VACCINIUM ASHEI READE) CULTIVARS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The mid-winter cold hardiness of 25 rabbiteye (V. ashei) blueberry cultivars was assayed across two years using a shoot freezing assay. LT50 values (i.e. temperature at which 50% of buds are damaged) for the cultivars ranged from -24.9 ºC for ‘Pearl River’ (a 50% V. ashei derivative) to -13.7 ºC for...

61

Back to chemical and other injuries Cold winter temperatures usually injure flower  

E-print Network

Back to chemical and other injuries Cold winter temperatures usually injure flower buds before buds may begin swelling, then die, whereas partially injured buds may develop only a few normal flowers. Injury can be assessed by dissecting buds: dead flower primordia are dark brown; live primordia are light

Isaacs, Rufus

62

Are Pectins Involved in Cold Acclimation and De-acclimation of Winter Oilseed Rape Plants?  

Microsoft Academic Search

† Background and Aims The hypothesis was tested that pectin content and methylation degree participate in regu- lation of cell wall mechanical properties and in this way may affect tissue growth and freezing resistance over the course of plant cold acclimation and de-acclimation. † Methods Experiments were carried on the leaves of two double-haploid lines of winter oil-seed rape (Brassica

DANUTA SOLECKA; J ACEK ZEBROWSKI; ALINA KACPERSKA

2008-01-01

63

The climatology of East Asian winter monsoon and cold surges from 1979--1995 NCEP/NCAR reanalyses  

SciTech Connect

The East Asian winter monsoon, which is associated with the Siberian high and active cold surges, is one of the most energetic monsoon circulation systems. The dramatic shift of northeasterlies and the outbreak of cold surges dominate the winter weather and local climate in the East Asian region, and may exert a strong impact on the extratropical and tropical planetary-scale circulations and influence the SSTs in the tropical western Pacific. General characteristics of the winter monsoon and cold surges and their possible link with tropical disturbances are revealed in many observational studies. Little attention has been given to the climatological aspects of the winter monsoon and cold surges. The purpose of this study is to compile and document the East Asian mean winter circulation, and present the climatology of cold surges and the Siberian high based on the 1979--1995 NCEP/NCAR reanalyses. Of particular interest is the interannual variation of winter monsoon circulation and cold surge events. Given that the cold surge activity and the Indonesian convection are much reduced during the 1982--83 period, one of the goals is to determine whether there exists a statistically significant relationship between ENSO and the interannual variation of winter monsoon and cold surges.

Yi Zhang; Sperber, K.; Boyle, J.

1996-04-01

64

Merging Cold Fronts in the Galaxy Pair NGC 7619 and NGC 7626  

E-print Network

We present results from {\\it Chandra} observations of the galaxy pair NGC 7619 and NGC 7626, the two dominant members of the Pegasus group. The X-ray images show a brightness edge associated with each galaxy, which we identify as merger cold fronts. The edges are sharp, and the axes of symmetry of the edges are roughly anti-parallel, suggesting that these galaxies are falling towards one another in the plane of the sky. The detection of merger cold fronts implies a merging subgroup scenario, since the alternative is that the galaxies are falling into a pre-existing $\\sim1$ keV halo without a dominant galaxy of its own, and such objects are not observed. We estimate the 3D velocities from the cold fronts and show that the velocity vectors are indeed most likely close to the plane of the sky, with a relative velocity of $\\sim1190\\kms$. The relative velocity is consistent with what is expected from the infall of two roughly equal mass subgroups whose total viral mass equals that of the Pegasus group. We conclude that the Pegasus cluster is currently forming from a major merger of two subgroups, dominated by NGC 7619 and NGC 7626. NGC 7626 contains a strong radio source, a core with two symmetric jets and radio lobes. Although we find no associated structure in the X-ray surface brightness map, the temperature map reveals a clump of cool gas just outside the southern lobe, presumably entrained by the lobe, and an extension of cooler gas into the lobe itself. The jet axis is parallel with the projected direction of motion of NGC 7626 (inferred from the symmetry axis of the merger cold front), and the southern leading jet is foreshortened as compared to the northern trailing one, possibly due to the additional ram pressure the forward jet encounters.

S. W. Randall; C. Jones; R. Kraft; W. R. Forman; E. O'Sullivan

2009-01-22

65

Merging Cold Fronts in the Galaxy Pair NGC 7619 and NGC 7626  

E-print Network

We present results from {\\it Chandra} observations of the galaxy pair NGC 7619 and NGC 7626, the two dominant members of the Pegasus group. The X-ray images show a brightness edge associated with each galaxy, which we identify as merger cold fronts. The edges are sharp, and the axes of symmetry of the edges are roughly anti-parallel, suggesting that these galaxies are falling towards one another in the plane of the sky. The detection of merger cold fronts implies a merging subgroup scenario, since the alternative is that the galaxies are falling into a pre-existing $\\sim1$ keV halo without a dominant galaxy of its own, and such objects are not observed. We estimate the 3D velocities from the cold fronts and show that the velocity vectors are indeed most likely close to the plane of the sky, with a relative velocity of $\\sim1190\\kms$. The relative velocity is consistent with what is expected from the infall of two roughly equal mass subgroups whose total viral mass equals that of the Pegasus group. We conclude...

Randall, S W; Kraft, R; Forman, W R; O'Sullivan, E

2008-01-01

66

Summer and winter drought in a cold desert ecosystem (Colorado Plateau) part II: effects on plant carbon assimilation and growth  

Microsoft Academic Search

We investigated the effects of winter and summer drought on a shrub\\/grass community of the Colorado Plateau in western North America, a winter-cold, summer-hot desert that receives both winter and summer precipitation. Summer, winter and yearlong drought treatments were imposed for 2 consecutive years using rainout shelters. We chose three perennial species for this study, representing different rooting patterns and

S. Schwinning; B. I. Starr; J. R. Ehleringer

2005-01-01

67

Ecological Technologies of a Chinese Traditional Folk House in Hot-Summer and Cold-Winter Zone  

E-print Network

on placement, plane and construction and so on with the climate variety. 2.1 The Climate Characters in Hot-summer and Cold-winter Zone Middle and lower reaches Yangtze River area is a typical hot-summer and cold-winter zone. This area includes... is reduced rapidly from east to west. Cold and humid are the climate characters in winter. Despite of the bad climate in Middle and lower reaches Yangtze River area, many technologies with zone characters, from site selection to details construction...

Xie, M.; Zhang, G.; Xu, F.

2006-01-01

68

Fine-scale observations of the structure and evolution of a tornadic cold front  

NASA Astrophysics Data System (ADS)

On 29 November 2011 a strong cold front crossed the UK. An intense, narrow rain band accompanied the front over northern England, along which several small tornadoes developed. The vertical structure of the front was sampled as it approached the UK, using dropsondes and in-situ aircraft measurements, as part of the DIAbatic influences on Mesoscale structures in ExTratropical storms (DIAMET) field campaign. One-minute-resolution data from the Met Office's network of automatic weather stations (AWSs) were used to investigate the structure of the surface front as it crossed the UK. 'Time-to-space' conversion of the AWS data, using a system motion vector estimated from sequences of radar data, permitted a fine-scale analysis of the surface frontal structure and its variation in the along-front direction. On the 28th, operational Unified Model output and aircraft dropsondes showed two separate fronts in the eastern Atlantic Ocean. By the morning of the 29th, dropsondes south of Ireland presented some features consistent with kata (also known as 'split') fronts, with two distinct, but overlapping dry intrusions, each overrunning saturated air below. Each dry intrusion was associated with a local maximum in the cross-front wind component, with a forward-directed, front-relative flow of ~ 5 - 10 m/s. Radar data showed the presence of multiple, narrow rain bands over Ireland and western extremities of the UK early on the 29th, as the front moved within range of the UK radar network. Over Ireland, the merger of at least two separate rain bands was observed. The merged band intensified and accelerated eastwards, leading to a single, intense, bowing line segment over northern England, along which the tornadoes occurred. In contrast, over southern England, no merger occurred, and the frontal zone was characterised by multiple rain bands for the duration of the observation period. The surface data showed markedly different structure in the temperature, wind and pressure fields in these two regions. Observational analyses, derived from the surface and dropsonde data, will be presented, with a particular focus on the observed differences in frontal structure over northern and southern England. Possible reasons for the differences will be discussed. A comparison with available operational model data will also be presented.

Clark, Matt; Rosenberg, Phil; Parker, Doug

2013-04-01

69

Arctic warming, atmospheric blocking and cold European winters in CMIP5 models  

NASA Astrophysics Data System (ADS)

Amplified Arctic warming is expected to have a significant long-term influence on the midlatitude atmospheric circulation by the latter half of the 21st century. Potential influences of recent and near future Arctic changes on shorter timescales are much less clear, despite having received much recent attention in the literature. In this letter, climate models from the recent CMIP5 experiment are analysed for evidence of an influence of Arctic temperatures on midlatitude blocking and cold European winters in particular. The focus is on the variability of these features in detrended data and, in contrast to other studies, limited evidence of an influence is found. The occurrence of cold European winters is found to be largely independent of the temperature variability in the key Barents-Kara Sea region. Positive correlations of the Barents-Kara temperatures with Eurasian blocking are found in some models, but significant correlations are limited.

Woollings, T.; Harvey, B.; Masato, G.

2014-01-01

70

Occurrence of shallow cold flows in the winter atmospheric boundary layer of interior of Alaska  

NASA Astrophysics Data System (ADS)

During winters, the absence of solar radiation combined with clear skies and weak synoptic forcing enables cold pooling in the complex topographic basins of interior Alaska. Under these conditions, shallow, small-scale cold flows originating within, or flowing from, north-facing semi-enclosed basins are able to penetrate the frigid atmospheric boundary layer (ABL) of the open south-facing basins. This paper introduces the Winter Boundary Layer Experiment carried out during three consecutive periods in Fairbanks (2009-2011) and examines observational results illustrating the changes in the mean and turbulent state of the ABL during the occurrence of shallow flows. Observations introduced here demonstrate that during flow penetration, surface layer stratification is destroyed allowing mixing and thermal stabilization of the basin cooling regime. Evidence of upper level ABL thermal turbulence related to shear driven flow is introduced and discussed. Basin-scale turbulent heat fluxes are shown to reach -20 Wm-2 during flow occurrence.

Fochesatto, Gilberto J.; Mayfield, John A.; Starkenburg, Derek P.; Gruber, Matthew A.; Conner, James

2013-10-01

71

The origin of cold fronts in the cores of relaxed galaxy clusters  

E-print Network

Chandra X-ray observations revealed the presence of cold fronts (sharp contact discontinuities between gas regions with different temperatures and densities) in the centers of many, if not most, relaxed clusters with cool cores. We use high-resolution simulations of idealized cluster mergers to show that they are due to sloshing of the cool gas in the central gravitational potential, which is easily set off by minor mergers and can persist for gigayears. The only necessary condition is a steep entropy profile, as observed in cooling flow clusters. Even if the infalling subcluster has no gas during core passage, the gravitational disturbance sets the main mass peak (gas and dark matter together) in motion relative to the surrounding gas. A rapid change in the direction of motion causes a change in ram pressure, which pushes the cool gas away from the dark matter peak and triggers sloshing. For nonzero impact parameters, the cool gas acquires angular momentum, resulting in a characteristic spiral pattern of cold fronts. There is little visible disturbance outside the cool core in such a merger. If the subcluster retains its gas during core passage, the cool central gas of the main cluster is more easily decoupled from the dark matter peak. Subsequently, some of that gas, and often the cool gas from the subcluster, falls back to the center and starts sloshing. However, in such a merger, global disturbances are readily visible in X-rays for a long time. We conclude that cold fronts at the centers of relaxed clusters, often spiral or concentric-arc in shape, are probably caused by encounters with small subhalos stripped of all their gas at the early infall stages.

Yago Ascasibar; Maxim Markevitch

2006-09-08

72

‘Only old ladies would do that’: Age stigma and older people’s strategies for dealing with winter cold  

Microsoft Academic Search

Concerns over the welfare of older people in winter have led to interventions and advice campaigns meant to improve their ability to keep warm, but older people themselves are not always willing to follow these recommendations. In this paper we draw on an in-depth study that followed twenty one older person households in the UK over a cold winter and

Rosie Day; Russell Hitchings

2011-01-01

73

Changes in winter cold surges over Southeast China: 1961 to 2012  

NASA Astrophysics Data System (ADS)

The present study investigates the overall changes in occurrences of winter cold surges over Southeast China for the period 1961-2012, using instrumental observations, reanalysis and model simulation datasets. Based on objectively defined criteria, cold surges were classified into 3 types according to their dynamical origin as inferred from daily evolution patterns of surface pressure systems with a focus on the Siberian High (SH): type A with an amplification of a quasi-stationary SH associated with high-pressure anomalies over the Ural mountains, type B with a developing SH associated with fast traveling upper-level waves, and type C with a high-pressure originated in the Arctic. Examination of the long-term change in cold surge occurrences shows different interdecadal variations among the 3 types. During 1961-2012, type A events (37.8%) decreased, while type B events, accounting for the majority (52.5%) of total winter cold surges, increased slightly. The contribution by type C to the total occurrence of the cold surges was small (8.8%) compared to that of A and B, but it became more frequent in the latest decade, related to the tendency of the Arctic Oscillation (AO) being more in its negative phase. Overall, we found slightly increased occurrences of cold surges over Southeast China since the early 1980s, despite the weakened SH intensity and warmer mean temperature compared to previous decades. The climate model projections of the phase 5 of the Coupled Model Intercomparison Project (CMIP5) suggests similar trend in the late 21st century under warmer climate.

Ou, Tinghai; Chen, Deliang; Jeong, Jee-Hoon; Linderholm, Hans W.; Zhou, Tianjun

2015-02-01

74

Changes in winter cold surges over Southeast China: 1961 to 2012  

NASA Astrophysics Data System (ADS)

The present study investigates the overall changes in occurrences of winter cold surges over Southeast China for the period 1961-2012, using instrumental observations, reanalysis and model simulation datasets. Based on objectively defined criteria, cold surges were classified into 3 types according to their dynamical origin as inferred from daily evolution patterns of surface pressure systems with a focus on the Siberian High (SH): type A with an amplification of a quasi-stationary SH associated with high-pressure anomalies over the Ural mountains, type B with a developing SH associated with fast traveling upper-level waves, and type C with a high-pressure originated in the Arctic. Examination of the long-term change in cold surge occurrences shows different interdecadal variations among the 3 types. During 1961-2012, type A events (37.8%) decreased, while type B events, accounting for the majority (52.5%) of total winter cold surges, increased slightly. The contribution by type C to the total occurrence of the cold surges was small (8.8%) compared to that of A and B, but it became more frequent in the latest decade, related to the tendency of the Arctic Oscillation (AO) being more in its negative phase. Overall, we found slightly increased occurrences of cold surges over Southeast China since the early 1980s, despite the weakened SH intensity and warmer mean temperature compared to previous decades. The climate model projections of the phase 5 of the Coupled Model Intercomparison Project (CMIP5) suggests similar trend in the late 21st century under warmer climate.

Ou, Tinghai; Chen, Deliang; Jeong, Jee-Hoon; Linderholm, Hans W.; Zhou, Tianjun

2015-01-01

75

Winter storm impacts on chenier plain coast of southwestern Louisiana  

Microsoft Academic Search

Stormy conditions associated with periodic winter cold front passages are closely related to transport of suspended sediment to the continental shelf, coastal erosion, and coastal progradation along shoreline sectors where abundant fine-grained sediments are stored on the inner shelf. Cold front passages occur between October and April on 3 to 5-day cycles. Their typical northwest to southeast direction of approach,

H. H. Roberts; O. K. Huh; S. A. Hsue; L. J. Jr. Rouse; D. A. Rickman

1989-01-01

76

Carbon dioxide variability during cold front passages and fair weather days at a forested mountaintop site  

NASA Astrophysics Data System (ADS)

This study describes temporal carbon dioxide (CO 2) changes at a new meteorological site on a mountaintop in the Virginia Blue Ridge Mountains during the first year of measurements. Continental mountaintop locations are increasingly being used for CO 2 monitoring, and investigations are needed to better understand measurements made at these locations. We focus on CO 2 mixing ratio changes on days with cold front passages and on fair weather days. Changes in CO 2 mixing ratios are largest during cold front passages outside the growing season and on clear, fair weather days in the growing season. 67% (60%) of the frontal passages during the non-growing (growing) season have larger postfrontal than prefrontal CO 2 mixing ratios. The increase in CO 2 mixing ratio around the frontal passage is short-lived and coincides with changes in CO and O 3. The CO 2 increase can therefore be used as an additional criterion to determine the timing of frontal passages at the mountaintop station. The CO 2 increase can be explained by an accumulation of trace gases along frontal boundaries. The magnitude and duration of the CO 2 increase is affected by the wind speed and direction that determine the source region of the postfrontal air. Southward-moving fronts result in the largest prolonged period of elevated CO 2, consistent with the postfrontal advection of air from the Northeastern United States where anthropogenic contributions are relatively large compared to other areas in the footprint of the mountaintop station. These anthropogenic contributions to the CO 2 changes are confirmed through concurrent CO measurements and output from NOAA's CarbonTracker model.

Lee, Temple R.; De Wekker, Stephan F. J.; Andrews, Arlyn E.; Kofler, Jonathan; Williams, Jonathan

2012-01-01

77

Adaptive Changes in ATPase Activity in the Cells of Winter Wheat Seedlings during Cold Hardening  

PubMed Central

A cytochemical study of ATPase activity in the cells of cold hardened and nonhardened winter wheat (Triticum aestivum L. cv. Nongke No. 1) seedlings was carried out by electron microscopic observation of lead phosphate precipitation. ATPase activity associated with various cellular organelles was altered during cold hardening. (a) At 22°C, high plasmalemma ATPase activity was observed in both cold hardened and nonhardened tissues; at 5°C, high activity of plasmalemma ATPase was observed in hardened tissues, but not in unhardened tissues. (b) In nonhardened tissues, tonoplast and vacuoles did not exhibit high ATPase activity at either 22 or 5°C, while in hardened tissues high activity was observed at both temperatures. (c) At 5°C, ATPase activity of nucleoli and chromatin was decreased in hardened tissues, but not in nonhardened tissues. It is suggested that adaptive changes in ATPase activity associated with a particular cellular organelle or membrane may be associated with the development of frost resistance of winter wheat seedlings. Images Fig. 1 Fig. 2 Fig. 3 PMID:16662432

Jian, Ling-Cheng; Sun, Long-Hua; Dong, He-Zhu

1982-01-01

78

Could the cold winter of 2009-2010 have been predicted?  

NASA Astrophysics Data System (ADS)

In parts of North America and Europe, the winter of 2009-2010 was one of the coldest and snowiest in recent history. These extreme weather patterns were likely the result of the strongly negative phase of the North Atlantic Oscillation (NAO). Researchers wondered whether this negative NAO could have been predicted. Jung et al. explored the origin and predictability of the unusually cold winter using numerical simulations and the European Centre for Medium-Range Weather Forecasts monthly forecasting system. They analyzed the possible role of various forcing mechanisms, including anomalies in sea surface temperature and sea ice, tropical atmospheric circulation, incoming solar radiation, and near-surface temperatures. The researchers found that none of these factors could account for the observed NAO anomaly, which could explain why most operational forecasting systems had trouble predicting the strongly negative NAO winter. The researchers suggest that internal atmospheric variability was primarily responsible for the negative NAO during the 2009-2010 winter. (Geophysical Research Letters, doi:10.1029/2011GL046786, 2011)

Tretkoff, Ernie

2011-05-01

79

Spatial Use by Wintering Greater White-Fronted Geese Relative to a Decade of Habitat Change in California's  

Microsoft Academic Search

We investigated the effect of recent habitat changes in California's Central Valley on wintering Pacific greater white-fronted geese (Anser albifrons frontalis) by comparing roost-to-feed distances, distributions, population range sizes, and habitat use during 1987-1990 and 1998- 2000. These habitat changes included wetland restoration and agricultural land enhancement due to the 1990 implementation of the Central Valley Joint Venture, increased land

JOSHUA T. ACKERMAN; JOHN Y. TAKEKAWA; DENNIS L. ORTHMEYER; JOSEPH P. FLESKES; JULIE L. YEE; KAMMIE L. KRUSE

80

Dynamics and ecological consequences of avian influenza virus infection in greater white-fronted geese in their winter staging areas.  

PubMed

Recent outbreaks of highly pathogenic avian influenza (HPAI) in poultry have raised interest in the interplay between avian influenza (AI) viruses and their wild hosts. Studies linking virus ecology to host ecology are still scarce, particularly for non-duck species. Here, we link capture-resighting data of greater white-fronted geese Anser albifrons albifrons with the AI virus infection data collected during capture in The Netherlands in four consecutive winters. We ask what factors are related to AI virus prevalence and whether there are ecological consequences associated with AI virus infection in staging white-fronted geese. Mean seasonal (low pathogenic) AI virus prevalence ranged between 2.5 and 10.7 per cent, among the highest reported values for non-duck species, and occurred in distinct peaks with near-zero prevalence before and after. Throat samples had a 2.4 times higher detection frequency than cloacal samples. AI virus infection was significantly related to age and body mass in some but not other winters. AI virus infection was not related to resighting probability, nor to maximum distance travelled, which was at least 191 km during the short infectious lifespan of an AI virus. Our results suggest that transmission via the respiratory route could be an important transmission route of AI virus in this species. Near-zero prevalence upon arrival on their wintering grounds, in combination with the epidemic nature of AI virus infections in white-fronted geese, suggests that white-fronted geese are not likely to disperse Asian AI viruses from their Siberian breeding grounds to their European wintering areas. PMID:20200028

Kleijn, D; Munster, V J; Ebbinge, B S; Jonkers, D A; Müskens, G J D M; Van Randen, Y; Fouchier, R A M

2010-07-01

81

Spatial Use by Wintering Greater White-Fronted Geese Relative to a Decade of Habitat Change in California's Central Valley  

Microsoft Academic Search

Abstract We investigated,the effect of recent,habitat changes,in California’s Central Valley on,wintering,Pacific greater,white-fronted,geese,(Anser albifrons frontalis) by comparing roost-to-feed distances, distributions, population range sizes, and habitat use during 1987–1990 and 1998– 2000. These habitat changes included wetland restoration and agricultural land enhancement,due to the 1990 implementation of the Central Valley Joint Venture, increased land area used for rice (Oryza sativa) production, and

JOSHUA T. ACKERMAN; JOHN Y. TAKEKAWA; DENNIS L. ORTHMEYER; JOSEPH P. FLESKES; JULIE L. YEE; KAMMIE L. KRUSE

2006-01-01

82

Dynamics and ecological consequences of avian influenza virus infection in greater white-fronted geese in their winter staging areas  

PubMed Central

Recent outbreaks of highly pathogenic avian influenza (HPAI) in poultry have raised interest in the interplay between avian influenza (AI) viruses and their wild hosts. Studies linking virus ecology to host ecology are still scarce, particularly for non-duck species. Here, we link capture–resighting data of greater white-fronted geese Anser albifrons albifrons with the AI virus infection data collected during capture in The Netherlands in four consecutive winters. We ask what factors are related to AI virus prevalence and whether there are ecological consequences associated with AI virus infection in staging white-fronted geese. Mean seasonal (low pathogenic) AI virus prevalence ranged between 2.5 and 10.7 per cent, among the highest reported values for non-duck species, and occurred in distinct peaks with near-zero prevalence before and after. Throat samples had a 2.4 times higher detection frequency than cloacal samples. AI virus infection was significantly related to age and body mass in some but not other winters. AI virus infection was not related to resighting probability, nor to maximum distance travelled, which was at least 191 km during the short infectious lifespan of an AI virus. Our results suggest that transmission via the respiratory route could be an important transmission route of AI virus in this species. Near-zero prevalence upon arrival on their wintering grounds, in combination with the epidemic nature of AI virus infections in white-fronted geese, suggests that white-fronted geese are not likely to disperse Asian AI viruses from their Siberian breeding grounds to their European wintering areas. PMID:20200028

Kleijn, D.; Munster, V. J.; Ebbinge, B. S.; Jonkers, D. A.; Müskens, G. J. D. M.; Van Randen, Y.; Fouchier, R. A. M.

2010-01-01

83

Winter variability of aeolian sediment transport threshold on a cold-climate dune  

NASA Astrophysics Data System (ADS)

Changes in surface conditions on cold-climate aeolian dunes are pronounced; during winter dunes are wet, snow covered, and/or frozen for extended periods of time. It is unknown how the critical wind speed for sediment transport (“threshold”) varies and how threshold may influence sediment transport predictions. Although the impact of surface conditions on threshold has been examined in synthetic experiments (wind tunnels), complicated feedbacks between threshold, sand transport, and surface conditions that occur in natural environments suggest that a ground-based empirical approach may provide enhanced insight. In this study we investigate threshold variability for 73 days during fall-winter-spring surface conditions from 18 November 2008 to 30 May 2009 in the Bigstick Sand Hills of Saskatchewan, Canada. Simultaneous measurements of threshold and atmospheric variables (air temperature, relative humidity, solar radiation, wind speed and direction) were used to examine the extent to which surface erodibility was regulated by meteorology. Time-lapse images of the surface from a co-located camera were used for quality control and interpreting changes in the surface affecting threshold. Results reveal that threshold varied throughout the deployment (25-75% quartiles: 6.92-8.28 m s- 1; mean: 7.79 m s- 1). Threshold variability was especially evident at two scales: (i) event timescale and (ii) seasonal timescale. Event-scale variability peaked during mid-winter; in one event the threshold varied by 6 m s- 1 in 2 h with freezing and re-freezing of the surface and relatively constant atmospheric conditions. The causes of event-scale variability are complex though qualitatively related to changes of wind direction, antecedent meteorological conditions, and vertical variations of grain-scale bonding agents such as pore ice and moisture. Seasonal-scale changes manifested as an increase in threshold during fall, peaking in mid-winter, and decreasing in spring. Increased threshold in mid-winter was linked to lower insolation and air temperature, suggesting low erodibility due to the presence of pore ice. Correlation coefficients of threshold versus atmospheric variables yielded relatively weak correlations (air temperature: r = - 0.322; relative humidity: r = 0.388; solar radiation: r = - 0.309) that also varied according to wind direction, suggesting that the link between atmospheric conditions and surface erodibility on cold-climate dunes is complex. This contrasts with results from field-based studies in warmer climates and controlled wind tunnel experiments, which show a more direct link between atmospheric variables (temperature and humidity) and surface erodibility. Nevertheless, our results do show a seasonal pattern of threshold that could be important for modeling cold-climate aeolian sediment transport.

Barchyn, Thomas E.; Hugenholtz, Chris H.

2012-12-01

84

Detecting spring after a long winter: coma or slow vigilance in cold, hypoxic turtles?  

PubMed Central

Many freshwater turtle species can spend the winter submerged in ice-covered lakes by lowering their metabolism, and it has been proposed that such severe metabolic depression render these turtles comatose. This raises the question of how they can detect the arrival of spring and respond in a sensible way to sensory information during hibernation. Using evoked potentials from cold or hypoxic turtles exposed to vibration and light, we show that hibernating turtles maintain neural responsiveness to light stimuli during prolonged hypoxia. Furthermore, turtles held under hibernation conditions for 14 days increase their activity when exposed to light or elevated temperatures, but not to vibration or increased oxygen. It is concluded that hibernating turtles are not comatose, but remain vigilant during overwintering in cold hypoxia, allowing them to respond to the coming of spring and to adjust their behaviour to specific sensory inputs. PMID:24108677

Madsen, Jesper G.; Wang, Tobias; Beedholm, Kristian; Madsen, Peter T.

2013-01-01

85

Characterization and effects of cold fronts in the Colombian Caribbean Coast and their relationship to extreme wave events  

NASA Astrophysics Data System (ADS)

Extreme ocean waves in the Caribbean Sea are commonly related to the effects of storms and hurricanes during the months of June through November. The collapse of 200 m of the Puerto Colombia pier in March 2009 revealed the effects of meteorological phenomena other than storms and hurricanes that may be influencing the extreme wave regime in the Colombian Caribbean. The marked seasonality of these atmospheric fronts was established by analyzing the meteorological-marine reports of Instituto de Hidrología, Meteorología y Estudios Ambientales of Colombia (IDEAM, based on its initials in Spanish) and Centro de Investigación en Oceanografía y Meteorología of Colombia (CIOH, based on its initials in Spanish). The highest occurrences were observed during the months of January, February, and March, with 6 fronts occurring per year. An annual trend was not observed, although the highest number of fronts occurred in 2010 (20 in total). An annual strong relationship between the maximum average wave values and the cold fronts, in the central zone of the Colombian Caribbean during the first three months of the year was established. In addition, the maximum values of the significant height produced by the passage of cold fronts during the last 16 yr were identified. Although the Colombian Caribbean has been affected by storms and hurricanes in the past, this research allows us to conclude that, there is a strong relationship between cold fronts and the largest waves in the Colombian Caribbean during the last 16 yr, which have caused damage to coastal infrastructure. We verified that the passage of a cold front corresponded to the most significant extreme wave event of the last two decades in the Colombian Caribbean, which caused the structural collapse of the Puerto Colombia pier, located near the city of Barranquilla, between 5 and 10 March 2009. This information is invaluable when evaluating average and extreme wave regimes for the purpose of informing the design of structures in this region of the Caribbean.

Ortiz-Royero, J. C.; Otero, L. J.; Restrepo, J. C.; Ruiz, J.; Cadena, M.

2013-07-01

86

Lunch Brie ng The winter of 2009-2010 broke snowfall accumulation and extreme cold records in cities and rural communities  

E-print Network

­ Lunch Brie ng ­ The winter of 2009-2010 broke snowfall accumulation and extreme cold records.S. is not the only nation experiencing harsh winters. Europe saw unprecedented snowfalls and record cold temperatures Geophysical Union (AGU), and the Weather Coalition. These sponsoring groups share in common a dedication

87

Summer and winter drought in a cold desert ecosystem (Colorado Plateau) part I: effects on soil water and plant water uptake  

Microsoft Academic Search

We investigated the effects of winter and summer drought on plants of the Colorado Plateau in western North America. This winter-cold, summer-hot desert region receives both winter and summer precipitation. Droughts were imposed for two consecutive years using rainout shelters. Here, we examine drought effects on the hydrologic interactions between plants and soil. We chose three perennial species for this

S. Schwinning; B. I. Starr; J. R. Ehleringer

2005-01-01

88

Research on winter-hardiness: deacclimation resistance, reacclimation ability, photoprotection strategies, and a cold acclimation protocol design  

Technology Transfer Automated Retrieval System (TEKTRAN)

Freezing is a major environmental stress during the annual cycle of temperate zone perennials. Freeze- injury can occur due to mid-winter temperatures that are colder than the tolerance threshold of a tissue / plant or due to untimely freezing temperatures before cold acclimation (development of fre...

89

The Study on Thermal Performance and Applicability of Energy-saving Wall Materials in Hot Summer and Cold Winter Zones  

E-print Network

-saving wall materials and thermal insulation systems used in projects in general, according to the climate in the zone combined with the design standard for the walls of residential buildings in the hot summer and cold winter zone. The results indicate...

Ren, W.; Lan, M.; Hao, Y.

2006-01-01

90

Influence of summer rainfall on root and shoot growth of a cold-winter desert shrub, Atriplex confertifolia  

Microsoft Academic Search

The influence of irrigation and nitrogen fertilization in early summer on root and shoot growth of Atriplex confertifolia, a C4 shrub species, was examined in a cold-winter desert community in northern Utah. Soil water and xylem pressure potentials were monitored during the summer period.

Ken C. Hodgkinson; Pat S. Johnson; Brien E. Norton

1978-01-01

91

The Effects of Cold Acclimation of Winter Wheat Plants on Changes in CO 2 Exchange and Phenolic Compound Formation  

Microsoft Academic Search

We studied CO2 exchange and phenolic compound production in various organs of unhardened and hardened winter wheat (Triticum aestivum L.) plants. The rates of CO2 assimilation at saturating illumination (photosynthesis) and CO2 evolution in darkness (respiration) declined substantially at the autumnal decrease of ambient temperature. However, because of a higher cold resistance of photosynthesis, the ratio of photosynthesis to respiration

N. V. Zagoskina; N. A. Olenichenko; S. V. Klimov; N. V. Astakhova; E. A. Zhivukhina; T. I. Trunova

2005-01-01

92

Can Winter-Active Bumblebees Survive the Cold? Assessing the Cold Tolerance of Bombus terrestris audax and the Effects of Pollen Feeding  

PubMed Central

There is now considerable evidence that climate change is disrupting the phenology of key pollinator species. The recently reported UK winter activity of the bumblebee Bombus terrestris brings a novel set of thermal challenges to bumblebee workers that would typically only be exposed to summer conditions. Here we assess the ability of workers to survive acute and chronic cold stress (via lower lethal temperatures and lower lethal times at 0°C), the capacity for rapid cold hardening (RCH) and the influence of diet (pollen versus nectar consumption) on supercooling points (SCP). Comparisons are made with chronic cold stress indices and SCPs in queen bumblebees. Results showed worker bees were able to survive acute temperatures likely to be experienced in a mild winter, with queens significantly more tolerant to chronic cold temperature stress. The first evidence of RCH in any Hymenoptera is shown. In addition, dietary manipulation indicated the consumption of pollen significantly increased SCP temperature. These results are discussed in the light of winter active bumblebees and climate change. PMID:24224036

Owen, Emily L.; Bale, Jeffrey S.; Hayward, Scott A. L.

2013-01-01

93

MAGNETOHYDRODYNAMIC SIMULATIONS OF THE FORMATION OF COLD FRONTS IN CLUSTERS OF GALAXIES: EFFECTS OF ANISOTROPIC VISCOSITY  

SciTech Connect

We carried out three-dimensional magnetohydrodynamic simulations to study the effects of plasma viscosity on the formation of sharp discontinuities of density and temperature distributions, cold fronts, in clusters of galaxies. By fixing the gravitational potential that confines the cool, dense plasma in a moving subcluster, we simulated its interaction with the hot, lower density plasma around the subcluster. At the initial state, the intracluster medium (ICM) is assumed to be threaded by uniform magnetic fields. The enhancement of plasma viscosity along the direction of magnetic fields is incorporated as anisotropic viscosity depending on the direction of magnetic fields. We found that the Kelvin-Helmholtz instability at the surface of the subcluster grows even in models with anisotropic viscosity, because its effects on the velocity shear across the magnetic field lines are suppressed. We also found that magnetic fields around the interface between the subcluster and ICM are amplified even in the presence of viscosity, while magnetic fields behind the subcluster are amplified up to {beta}{sup -1} {approx} 0.01 in models with viscosity, whereas they are amplified up to {beta}{sup -1} {approx} 0.1 in models without viscosity, where {beta} is the ratio of gas pressure to magnetic pressure.

Suzuki, Kentaro; Ogawa, Takayuki; Matsumoto, Yosuke; Matsumoto, Ryoji, E-mail: suzukikn@astro.s.chiba-u.ac.jp, E-mail: ogawa@astro.s.chiba-u.ac.jp, E-mail: ymatumot@astro.s.chiba-u.ac.jp, E-mail: matumoto@astro.s.chiba-u.ac.jp [Department of Physics, Graduate School of Science, Chiba University, Inage-ku, Chiba 263-8522 (Japan)

2013-05-10

94

Improved management of winter operations to limit subsurface contamination with degradable deicing chemicals in cold regions.  

PubMed

This paper gives an overview of management considerations required for better control of deicing chemicals in the unsaturated zone at sites with winter maintenance operations in cold regions. Degradable organic deicing chemicals are the main focus. The importance of the heterogeneity of both the infiltration process, due to frozen ground and snow melt including the contact between the melting snow cover and the soil, and unsaturated flow is emphasised. In this paper, the applicability of geophysical methods for characterising soil heterogeneity is considered, aimed at modelling and monitoring changes in contamination. To deal with heterogeneity, a stochastic modelling framework may be appropriate, emphasizing the more robust spatial and temporal moments. Examples of a combination of different field techniques for measuring subsoil properties and monitoring contaminants and integration through transport modelling are provided by the SoilCAM project and previous work. Commonly, the results of flow and contaminant fate modelling are quite detailed and complex and require post-processing before communication and advising stakeholders. The managers' perspectives with respect to monitoring strategies and challenges still unresolved have been analysed with basis in experience with research collaboration with one of the case study sites, Oslo airport, Gardermoen, Norway. Both scientific challenges of monitoring subsoil contaminants in cold regions and the effective interaction between investigators and management are illustrated. PMID:24281673

French, Helen K; van der Zee, Sjoerd E A T M

2014-08-01

95

Geographic variation in Bar-headed geese Anser indicus: connectivity of wintering and breeding grounds across a broad front.  

USGS Publications Warehouse

The connectivity and frequency of exchange between sub-populations of migratory birds is integral to understanding population dynamics over the entire species' range. True geese are highly philopatric and acquire lifetime mates during the winter, suggesting that the number of distinct sub-populations may be related to the number of distinct wintering areas. In the Bar-headed Goose Anser indicus, a species found exclusively in Central Asia, the connectivity between breeding and wintering areas is not well known. Their migration includes crossing a broad front of the Himalaya Cordillera, a significant barrier to migration for most birds. Many Bar-headed Geese fly to breeding areas on the Tibetan-Qinghai Plateau (TQP), the highest plateau in the world. From 2005-2008, 60 Bar-headed Geese were captured and marked with satellite transmitters in Nepal (n = 2), India (n = 6), China (n = 29), and Mongolia (n = 23) to examine their migration and distribution. Distinct differences were observed in their migration corridors and timing of movements, including an apparent leap-frog migration pattern for geese from Mongolia. Measurements of geese from Mongolia were larger than their counterparts from China, providing some evidence of morphological differences. Alteration of habitats in China, including the warming effects of climate change on glaciers increasing runoff to TQP wetlands, may be changing goose migration patterns and timing. With the exception of one individual, all geese from Qinghai Lake, China wintered in the southern TQP near Lhasa, and their increasing numbers in that region may be related to the effects of climate change and agricultural development. Thus, our findings document both morphological and geographical variation in sub-populations of Bar-headed Geese, but their resilience to environmental change may be lost if migratory short-stopping results in larger congregations restricted to a smaller number of wintering areas.

Takekawa, John Y.; Heath, Shane R.; Douglas, David C.; Perry, William M.; Javed, Salim; Newman, Scott H.; Suwal, Rajendra N.; Rahman, Asad R.; Choudhury, Binod C.; Prosser, Diann J.; Yan, Baoping; Hou, Yuansheng; Batbayar, Nyambayar; Natsagdorj, Tseveenmayadag; Bishop, Charles M.; Butler, Patrick J.; Frappell, Peter B.; Milsom, William K.; Scott, Graham R.; Hawkes, Lucy A.; Wikelski, Martin

2009-01-01

96

Geographic variation in Bar-headed Geese Anser indicus: Connectivity of wintering areas and breeding grounds across a broad front  

USGS Publications Warehouse

The connectivity and frequency of exchange between sub-populations of migratory birds is integral to understanding population dynamics over the entire species' range. True geese are highly philopatric and acquire lifetime mates during the winter, suggesting that the number of distinct sub-populations may be related to the number of distinct wintering areas. In the Bar-headed Goose Anser indicus, a species found exclusively in Central Asia, the connectivity between breeding and wintering areas is not well known. Their migration includes crossing a broad front of the Himalaya Cordillera, a significant barrier to migration for most birds. Many Bar-headed Geese fly to breeding areas on the Tibetan-Qinghai Plateau (TQP), the highest plateau in the world. From 2005-2008, 60 Bar-headed Geese were captured and marked with satellite transmitters in Nepal (n = 2), India (n = 6), China (n = 29), and Mongolia (n = 23) to examine their migration and distribution. Distinct differences were observed in their migration corridors and timing of movements, including an apparent leap-frog migration pattern for geese from Mongolia. Measurements of geese from Mongolia were larger than their counterparts from China, providing some evidence of morphological differences. Alteration of habitats in China, including the warming effects of climate change on glaciers increasing runoff to TQP wetlands, may be changing goose migration patterns and timing. With the exception of one individual, all geese from Qinghai Lake, China wintered in the southern TQP near Lhasa, and their increasing numbers in that region may be related to the effects of climate change and agricultural development. Thus, our findings document both morphological and geographical variation in sub-populations of Bar-headed Geese, but their resilience to environmental change may be lost if migratory short-stopping results in larger congregations restricted to a smaller number of wintering areas. ?? Wildfowl & Wetlands Trust.

Takekawa, J.Y.; Heath, S.R.; Douglas, D.C.; Perry, W.M.; Javed, S.; Newman, S.H.; Suwal, R.N.; Rahmani, A.R.; Choudhury, B.C.; Prosser, D.J.; Yan, B.; Hou, Y.; Batbayar, N.; Natsagdorj, T.; Bishop, C.M.; Butler, P.J.; Frappell, P.B.; Milsom, W.K.; Scott, G.R.; Hawkes, L.A.; Wikelski, M.

2009-01-01

97

Sloshing Cold Fronts in Galaxy Groups and their Perturbing Disk Galaxies: An X-Ray, Optical, and Radio Case Study  

NASA Astrophysics Data System (ADS)

We present a combined X-ray, optical, and radio analysis of the galaxy group IC 1860 using the currently available Chandra and XMM data, multi-object spectroscopy data from the literature, and Giant Metrewave Radio Telescope (GMRT) data. The Chandra and XMM imaging and spectroscopy reveal two surface brightness discontinuities at 45 and 76 kpc shown to be consistent with a pair of cold fronts. These features are interpreted as due to sloshing of the central gas induced by an off-axis minor merger with a perturber. This scenario is further supported by the presence of a peculiar velocity of the central galaxy IC 1860 and the identification of a possible perturber in the optically disturbed spiral galaxy IC 1859. The identification of the perturber is consistent with the comparison with numerical simulations of sloshing. The GMRT observation at 325 MHz shows faint, extended radio emission contained within the inner cold front, as seen in some galaxy clusters hosting diffuse radio mini-halos. However, unlike mini-halos, no particle reacceleration is needed to explain the extended radio emission, which is consistent with aged radio plasma redistributed by the sloshing. There is a strong analogy between the X-ray and optical phenomenology of the IC 1860 group and that of two other groups, NGC 5044 and NGC 5846, showing cold fronts. The evidence presented in this paper is among the strongest supporting the currently favored model of cold-front formation in relaxed objects and establishes the group scale as a chief environment for studying this phenomenon.

Gastaldello, Fabio; Di Gesu, Laura; Ghizzardi, Simona; Giacintucci, Simona; Girardi, Marisa; Roediger, Elke; Rossetti, Mariachiara; Brighenti, Fabrizio; Buote, David A.; Eckert, Dominique; Ettori, Stefano; Humphrey, Philip J.; Mathews, William G.

2013-06-01

98

SLOSHING COLD FRONTS IN GALAXY GROUPS AND THEIR PERTURBING DISK GALAXIES: AN X-RAY, OPTICAL, AND RADIO CASE STUDY  

SciTech Connect

We present a combined X-ray, optical, and radio analysis of the galaxy group IC 1860 using the currently available Chandra and XMM data, multi-object spectroscopy data from the literature, and Giant Metrewave Radio Telescope (GMRT) data. The Chandra and XMM imaging and spectroscopy reveal two surface brightness discontinuities at 45 and 76 kpc shown to be consistent with a pair of cold fronts. These features are interpreted as due to sloshing of the central gas induced by an off-axis minor merger with a perturber. This scenario is further supported by the presence of a peculiar velocity of the central galaxy IC 1860 and the identification of a possible perturber in the optically disturbed spiral galaxy IC 1859. The identification of the perturber is consistent with the comparison with numerical simulations of sloshing. The GMRT observation at 325 MHz shows faint, extended radio emission contained within the inner cold front, as seen in some galaxy clusters hosting diffuse radio mini-halos. However, unlike mini-halos, no particle reacceleration is needed to explain the extended radio emission, which is consistent with aged radio plasma redistributed by the sloshing. There is a strong analogy between the X-ray and optical phenomenology of the IC 1860 group and that of two other groups, NGC 5044 and NGC 5846, showing cold fronts. The evidence presented in this paper is among the strongest supporting the currently favored model of cold-front formation in relaxed objects and establishes the group scale as a chief environment for studying this phenomenon.

Gastaldello, Fabio; Di Gesu, Laura; Ghizzardi, Simona; Rossetti, Mariachiara [IASF-Milano, INAF, via Bassini 15, I-20133 Milan (Italy); Giacintucci, Simona [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States); Girardi, Marisa [Dipartimento di Fisica, Universita degli Studi di Trieste, Sezione di Astronomia, via Tiepolo 11, I-34133 Trieste (Italy); Roediger, Elke [Jacobs University Bremen, P.O. Box 750 561, D-28725 Bremen (Germany); Brighenti, Fabrizio [Dipartimento di Astronomia, Universita di Bologna, via Ranzani 1, I-40127 Bologna (Italy); Buote, David A.; Humphrey, Philip J. [Department of Physics and Astronomy, University of California at Irvine, 4129 Frederick Reines Hall, Irvine, CA 92697-4575 (United States); Eckert, Dominique [ISDC Data Centre for Astrophysics, Geneva Observatory, ch. d'Ecogia, 16, CH-1290 Versoix (Switzerland); Ettori, Stefano [INAF, Osservatorio Astronomico di Bologna, via Ranzani 1, I-40127 Bologna (Italy); Mathews, William G. [UCO/Lick Observatory, University of California at Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States)

2013-06-10

99

VHF Radar Observations of Gravity-Wave Production by Cold Fronts over Southern Australia.  

NASA Astrophysics Data System (ADS)

Four extended observational campaigns were conducted during August and November 1988 with an ST (stratosphere-troposphere) radar in southern Australia during the passage of cold fronts over the system, giving around 30 days of three-dimensional wind measurements with 15-min time and 0.5-km height resolution over the 2-11.5-km height range. Order of magnitude increases in the variance of time-fluctuating wind velocities were measured during frontal passages, which are definitively ascribed to gravity waves. The time-height morphology of the horizontal- and vertical-velocity fluctuations differed. Bursts of horizontal-velocity variance 2 + 2 10-100 m2 s2 arose at upper levels about a day before the frontal boundary arrived, and this activity gradually extended to lower heights as the front neared. The arrival of the frontal boundary marked a sudden reduction in this activity. After the frontal boundary passed, reduced activity persisted for 12 hours, after which bursts in 2 + 2 returned at upper levels and persisted typically for about a day. These bursts arose in regions of high mean wind speeds (20-50 m s1), and analysis associates this activity with a spectrum of many saturating inertia-gravity waves with long horizontal wavelengths and large ground-based phase speeds. Strong interaction between the waves and the mean flow is likely. In contrast, bursts in vertical-velocity fluctuations, w, were confined almost entirely to the troposphere and were quasi-sinusoidal in appearance. These fluctuations are ascribed to gravity waves with high intrinsic frequencies. Significant w amplitudes were evident both after and prior to frontal passage, but the largest amplitudes (w 0.5 m s1) occurred with the onset of strong vertical circulation when the frontal boundary arrived. The smaller w amplitudes observed in the stratosphere are due in part to the more oblique propagation of wave energy in this more stable environment, but may also reflect vertical ducting of this activity at altitudes of small static stability just below the tropopause. Two clear cases of ducted w oscillations are identified with the aid of radiosonde temperature data from a nearby site. Comparisons between these measurements and the limited numerical modeling of frontal gravity waves show some similarities in wave characteristics.

Eckermann, Stephen D.; Vincent, Robert A.

1993-03-01

100

Calcium interacts with antifreeze proteins and chitinase from cold-acclimated winter rye.  

PubMed

During cold acclimation, winter rye (Secale cereale) plants accumulate pathogenesis-related proteins that are also antifreeze proteins (AFPs) because they adsorb onto ice and inhibit its growth. Although they promote winter survival in planta, these dual-function AFPs proteins lose activity when stored at subzero temperatures in vitro, so we examined their stability in solutions containing CaCl2, MgCl2, or NaCl. Antifreeze activity was unaffected by salts before freezing, but decreased after freezing and thawing in CaCl2 and was recovered by adding a chelator. Ca2+ enhanced chitinase activity 3- to 5-fold in unfrozen samples, although hydrolytic activity also decreased after freezing and thawing in CaCl2. Native PAGE, circular dichroism, and Trp fluorescence experiments showed that the AFPs partially unfold after freezing and thawing, but they fold more compactly or aggregate in CaCl2. Ruthenium red, which binds to Ca(2+)-binding sites, readily stained AFPs in the absence of Ca2+, but less stain was visible after freezing and thawing AFPs in CaCl2. We conclude that the structure of AFPs changes during freezing and thawing, creating new Ca(2+)-binding sites. Once Ca2+ binds to those sites, antifreeze activity, chitinase activity and ruthenium red binding are all inhibited. Because free Ca2+ concentrations are typically low in the apoplast, antifreeze activity is probably stable to freezing and thawing in planta. Ca2+ may regulate chitinase activity if concentrations are increased locally by release from pectin or interaction with Ca(2+)-binding proteins. Furthermore, antifreeze activity can be easily maintained in vitro by including a chelator during frozen storage. PMID:15122015

Stressmann, Maja; Kitao, Satoshi; Griffith, Marilyn; Moresoli, Christine; Bravo, León A; Marangoni, Alejandro G

2004-05-01

101

Spatial use by wintering greater white-fronted geese relative to a decade of habitat change in California's Central Valley  

USGS Publications Warehouse

We investigated the effect of recent habitat changes in California's Central Valley on wintering Pacific greater white-fronted geese (Anser albifrons frontalis) by comparing roost-to-feed distances, distributions, population range sizes, and habitat use during 1987-1990 and 1998-2000. These habitat changes included wetland restoration and agricultural land enhancement due to the 1990 implementation of the Central Valley Joint Venture, increased land area used for rice (Oryza sativa) production, and the practice of flooding, rather than burning, rice straw residues for decomposition because of burning restrictions enacted in 1991. Using radiotelemetry, we tracked 192 female geese and recorded 4,516 locations. Geese traveled shorter distances between roosting and feeding sites during 1998-2000 (24.2 ?? 2.2 km) than during 1987-1990 (32.5 ?? 3.4 km); distance traveled tended to decline throughout winter during both decades and varied among watershed basins. Population range size was smaller during 1998-2000 (3,367 km2) than during 1987-1990 (5,145 km2), despite a 2.2-fold increase in the size of the Pacific Flyway population of white-fronted geese during the same time period. The population range size also tended to increase throughout winter during both decades. Feeding and roosting distributions of geese also differed between decades; geese shifted into basins that had the greatest increases in the amount of area in rice production (i.e., American Basin) and out of other basins (i.e., Delta Basin). The use of rice habitat for roosting (1987-1990: 40%, 1998-2000: 54%) and feeding (1987-1990: 57%, 1998-2000: 72%) increased between decades, whereas use of wetlands declined for roosting (1987-1990: 36%, 1998-2000: 31%) and feeding (1987-1990: 22%, 1998-2000: 12%). Within postharvested rice habitats, geese roosted and fed primarily in burned rice fields during 1987-1990 (roost: 43%, feed: 34%), whereas they used flooded rice fields during 1998-2000 (roost: 78%, feed: 64%). Our results suggest that white-fronted geese have altered their spatial use of California's Central Valley during the past decade in response to changing agricultural practices and the implementation of the Central Valley Joint Venture.

Ackerman, J.T.; Takekawa, J.Y.; Orthmeyer, D.L.; Fleskes, J.P.; Yee, J.L.; Kruse, K.L.

2006-01-01

102

The Central American cold surge: an observational analysis of the deep southward penetration of North American cold fronts  

E-print Network

LIST OF TABLES Table 1. List of North, Central and South American surface and upper air reporting stations 2. Annual and monthly CACS events 3. CACS event statistics for the 1979-1980 winter season. . . Page 20 29 . . . 166 4. CACS event... UTC . . . , . . . . . . . . . , . . . . , . . . . . . . . , . . . ? ? . . . . , . . . . . , . . . . . , . . . . . . . 1 1 4 71 GOES IR satellite image with MB enhancement from 28 January 1988, 1831 UTC...

Reding, Philip John

1992-01-01

103

A model study of the effects of river discharges and interannual variation of winds on the plume front in winter in Pearl River Estuary  

NASA Astrophysics Data System (ADS)

A three-dimensional numerical model, Estuarine, Coastal and Ocean Modeling System with Sediments (ECOMSED), is employed to study the mechanism of plume front in the Pearl River Estuary (PRE) in detail. The model is forced by winds, tides and river discharges. The modeled results of tidal elevation, current velocity and salinity are in reasonable agreement with observational data in the PRE. By analyzing momentum and saltwater transport balance equations, it is found that the wind stress term, the pressure gradient term and the local time derivative term of velocity are dominant in the momentum equation, while the local time derivative term, the horizontal advective term and the vertical mixing term of salinity are dominant in the salinity transport equation. The residual current at surface along the plume front is seaward and stronger, whilst that in the bottom layer is mainly landward. A series of sensitive experiments is also run to examine the responses of plume front to changes of river discharges at different inlets in Lingdingyang Bay and interannual variation of northeast winds in winter. The location of plume front responds differently to the change of river discharge at different inlets. An increase in the river discharge at Dahu inlet seems to affect the location of plume front most among the four river inlets, it makes the plume front move eastward and southward wholly; the variation of river discharge at Nansha or Fengmamiao inlet on the location of plume front is more local and weaker; whilst the variation of river discharge at Hengmen inlet has little effect on the plume front. The location of plume front also changes in response to the interannual variation of northeast winds in winter, the stronger or the more eastward the winds are, the more westward the plume front moves, and only in the northern PRE, the response of plume front to the variation of wind speeds is largely different from that to the variation of wind directions.

Zheng, Shu; Guan, Weibing; Cai, Shuqun; Wei, Xing; Huang, Daji

2014-02-01

104

Mid-American Review of Sociology, Volume 9, Number 2 (WINTER, 1984): Front Matter  

E-print Network

ISSN: 0732-913X Edited at the Department of Sociology, University of Kansas Book Review Editor DANIEL R. WILDCAT ALBERT DICHIARA KENNETH BENSON University of Missouri-Columbia Business Manager KATHLEEN STANLEY MICHAEL R. HILL HUGH P. WHITT... ROBERT DAUGHERTY DUANE EVANS Haskell Indian Junior College W. RICHARD STEPHENS, JR. Greenville College Mid-American Review of Sociology Mid-American Review of Sociology Sponsors CHAPMAN COLLEGE Department of Sociology WINTER, 1984 CONTENTS Contributors...

1984-01-01

105

Mid-American Review of Sociology, Volume 8, Number 2 (WINTER, 1983): Front Matter  

E-print Network

ISSN: 0732-913X Edited at the Department of Sociology, University of Kansas Supervising Editors SCOTT MCNALL ROBERT ANTONIO Business Manager KATHLEEN STANLEY Article Review Editor PATRICK AKARD Book Review Editor DANIEL R. WILDCAT JENA HILLIARD... Kansas State University KATHRYN DEITZ RICHARD A. WRIGHT Mcpherson College RACHAELJ. WARD ROBERT W. BILBY University of Wisconsin-LaCrosse MARY WHITE STEWART University of Missouri-Kansas City Mid-American Review of Sociology WINTER, 1983 Vol. VIII, No.2...

1983-01-01

106

Requirement of a CCGAC cis-acting element for cold induction of the BN115 gene from winter Brassica napus  

Microsoft Academic Search

Mutation of the core pentamer, CCGAC, of two putative low temperature responsive elements (LTREs) in the 5'-proximal region of the winter Brassica napus cold-induced gene BN115 was carried out. Analyses of transient expression of the resultant mutated BN115 promoter-GUS fusions revealed the loss of low-temperature regulation by the promoter. This indicates that the CCGAC sequence is critical to the low-temperature

Chao Jiang; Betty Iu; Jas Singh

1996-01-01

107

Cold, Northern Winters: The Importance of Temperature to Overwinter Mortality of Age0 White Crappies  

Microsoft Academic Search

Survival during the first winter of life can influence the recruitment of many fishes. We used field sampling and laboratory experiments to explore the mechanisms underlying first winter growth and survival of white crappie Pomoxis annularis, which exhibits variable recruitment. We sampled age-0 white crappies from four Ohio reservoirs before winter to evaluate whether large individuals had a greater energy

Arthur B. McCollum; David B. Bunnell; Roy A. Stein

2003-01-01

108

Meso and microscale features of the lower portion of cold fronts  

E-print Network

than the sea-breeze fronts+ of the area which are a diurnal phenomena. Berson defined the top of a wind shear layer, found to be associated with cool changes, as the point where the wind direction first became quasi-constant with height. The base... of the shear layer was found as the point above which +I'he sea-breeze front is defined as a front along which cool and moist air from the sea replaces warm and dry air over land. It is caused by the diurnal variation in the horizontal pressure field...

Beniura, Hideo

1962-01-01

109

Creation and tidal advection of a cold salinity front in Storfjorden: 1. Polynya dynamics  

NASA Astrophysics Data System (ADS)

Hydrographical measurements from the Storfjorden polynya document the presence of an abrupt front in near-freezing water dividing saline water recently created by a polynya event, from less saline water originating further south. This event occurred days before the survey with estimated heat flux ˜400 W m-2 over the polynya. Brine-enriched shelf water (BSW) is observed downslope toward deeper parts of Storfjorden, and BSW from earlier polynya events overflows the sill. Current measurements from a nearby sound, Freemansundet, document tidal currents exceeding 80 cm s-1 that displaced the front back and forth beneath the measurement site on fast ice ˜400 m from the polynya edge. Front displacement of ˜12 km is documented and mainly due to the M2 component superimposed on a mean residual current of 0.28 m s-1 into the sound induced by southerly wind during the survey. Complex topography imposes baroclinic tidal currents with strong vertical shear in the fast ice-covered sound, and with significant cross-channel flow. Supercooling events indicated in the hydrographical time series, and likely enhanced frazil ice production, are associated with double-diffusive turbulent mixing when the salinity front passes. In this way, these measurements indicate a novel ice production process along the edge of tidally induced latent heat polynyas where salinity fronts are generated. Turbulence increases (decreases) during flood (ebb) due to the destabilization (stabilization) of the water column when the salinity front passes the measurement site. Double-diffusive turbulent mixing related to tidal advection of salinity front below fast ice is pursued in a companion paper.

Skogseth, Ragnheid; McPhee, Miles G.; Nilsen, Frank; Smedsrud, Lars H.

2013-07-01

110

The solar influence on the probability of relatively cold UK winters in the future This article has been downloaded from IOPscience. Please scroll down to see the full text article.  

E-print Network

that relatively cold UK winters are more common when solar activity is low (Lockwood et al 2010 Environ. Res. LettThe solar influence on the probability of relatively cold UK winters in the future This article has) 034004 (11pp) doi:10.1088/1748-9326/6/3/034004 The solar influence on the probability of relatively cold

Lockwood, Mike

111

Influences of Arctic Oscillation and Madden-Julian Oscillation on cold surges and heavy snowfalls over Korea: A case study for the winter of 2009–2010  

Microsoft Academic Search

In the winter of 2009–2010, frequent and long-lasting cold weather affected Korea. Four major cold surges and several heavy snowfall events were observed, including a record-breaking event on 4 January 2010. These four cold surges had distinct properties with regard to their relationships to the phases of the Arctic Oscillation (AO) and the Madden-Julian Oscillation (MJO), suggesting the possible influences

Tae-Won Park; Chang-Hoi Ho; Song Yang; Jee-Hoon Jeong

2010-01-01

112

Extreme temperature contrast of the year 2012 in Greece: An exceptionally cold winter and a record breaking summer  

NASA Astrophysics Data System (ADS)

During the past decade several regions all over Europe have experienced severe heat waves with serious social and environmental impacts. The year of 2003 was characterized by record breaking high temperatures for central Europe, while the year of 2007 was a remarkably warm year of the majority of the Eastern Mediterranean. During this year, three major heat waves were detected in Greece during summer and abnormally high temperatures were also observed through the cold season of 2007. It was found that the winter minimum temperatures were statistically more extreme than the summer maxima. Moreover, exceptionally high maximum and minimum temperatures occurred in November of 2010 affection the entire Greek region while September of the following year was also characterized by large departures of maximum temperatures from the long term mean values and the highest minimum temperature average in comparison to the reference period 1958-2000. The past year (2012) could also be characterized as a year of extremes. This time a temperature contrast was detected in the domain of study with a prolonged cold - season spell during winter and new record - breaking extreme maximum and minimum summer temperatures. More specifically it was found that the summer of 2012 was the warmest one since 1958. The whole season was characterized by long - lasting warm conditions with large departures from the long term (up to 4oC for Tmax) and this warming phenomenon was more intense during July and August. In contrast the winter season (December 2011 - February 2012) was found to be in the ten coldest winters of the last 55 years. The departures from the mean are lower than summer (1oC to 1.5oC negative anomalies) but most of the days were found to have lower Tmax, Tmin and Tmean values than the average daily temperatures of the period 1958-2000. Finally, it is worth mentioning that the year of 2012 was characterized by the highest annual temperature range reaching up to 26oC in several stations. Consequently, these abnormal cold (warm) conditions during the winter (summer) months motivated the present study in order to conduct a statistical analysis of these temperature extremes and their characteristics in addition to an investigation of the synoptic large scale atmospheric conditions which possibly result to this year of contrasts. Acknowledgments: This study has been supported by the Research Committee of the Aristotle University of Thessaloniki.

Tolika, Konstantia; Anagnostopoulou, Christina; Maheras, Panagiotis; Velikou, Kondylia

2013-04-01

113

ANALYTICAL APPROACH THE MASS DISTRIBUTION FUNCTION SUBHALOS AND COLD FRONTS GALAXY CLUSTERS  

E-print Network

Fujita, Craig Sarazin, 2 Masahiro Nagashima, 1 Taihei Yano Received January accepted May ABSTRACT galaxies: clusters: general galaxies: halos large­scale structure of universe X­rays: galaxies: clusters dark matter, the cold dark matter (CDM) theory vides a remarkably successful description large­scale

Sarazin, Craig

114

Shelf circulation prior to and post a cold front event measured from vessel-based acoustic Doppler current profiler  

NASA Astrophysics Data System (ADS)

Shelf circulation impacted by a shift in wind regime during the passage of an atmospheric cold front system is studied with a field survey over the mid-shelf of the South Atlantic Bight between Oct 4 and 9, 2004. Weak southerly winds preceded the cold front for a few days, followed by a rapid shift in wind direction and strengthening of northeasterly winds over a few more days. More than 93 h of acoustic Doppler current profiler (ADCP) data were obtained along an equilateral triangle of 105 km in perimeter, which was continuously occupied for 11 times. A harmonic analysis was applied to extract tidal and subtidal wind-driven flow components by collapsing the 93 hour data into one M2 tidal period. It was found that the cross-shelf flow was barely affected by the wind while the along-shelf flow responded with a spatially uniform and almost steadily increasing mean flow velocity, superimposed on an oscillatory tidal current. The wind induced along-shelf transport was estimated to be ~ 0.3 Sv over the inner and middle shelf. The net cross-shelf transport was negligible. Apparently, the northeasterly wind causes an along-shelf current which was subject to Coriolis force that sets up an increasing coastal sea level pressure gradient as the water kept piling up against the coast, which was confirmed by tide gauge data. The observations found that the flow field prior to the strong winds had more complicated structures including eddy-like features, while after the strong northeasterly winds, the flow became eddy free and uniform in space. A theoretical model solved by a Laplace Transform was used to examine the wind-driven flow mechanism and the results were compared with the observations of net along-shelf flow velocity.

Li, Chunyan; Chen, Changsheng

2014-11-01

115

Comparison of subjective symptoms and cold prevention measures in winter between traffic control workers and construction workers in Japan.  

PubMed

To help making comfortable workplaces and to prevent health disorders induced by the exposure to moderate cold in two different groups of out-door workers, we conducted a survey to compare subjective symptoms and cold prevention measures in winter between traffic control workers and construction workers. The subjects of this study were 98 male traffic control workers and 149 male workers engaged in building construction. Work loads of traffic control workers and construction workers were estimated at RMR1-2 and RMR2-4, respectively. All subjects were asked to complete a self-administered questionnaire covering age, occupational career, working figure, present illness, past history of diseases, individual preventive measures to the cold, subjective symptoms in the winter (43 items) and subjective symptoms occurred during daytime working in the winter (6 items). In two parts of the construction workplaces (the place where a morning assembly was held and on the 7th floor of the construction site) dry bulb, wet bulb and globe temperatures were measured in January. Windchill Index (kcal/cm,(2) x h) was calculated by the measured dry bulb temperature and wind velocity. Mean values of dry bulb temperature between 9:00 and 16:30 in the place where a morning assembly was held for three days were between 4.8 +/- 1.2 degrees C at 9:00 am and 9.3 +/- 1.1 degrees C at noon. Mean values of Windchill Index in the place where a morning assembly was held were between 490.8+/-23.9 kcal/cm(2) x h at 9:30 am and 608.2+/-47.3 kcal/cm(2) x h at 2:30 pm. Occupational career, monthly working days, daily working hours, one way commuting hours, and daily smoking numbers of the traffic control workers were significantly shorter than the construction workers (p<0.01). There were no significant differences in the prevalence of chillness in the arms and legs between the traffic control workers (5.1%) and the construction workers (0.7%). Prevalence of wearing a warm underwear, body warmer, warm trousers, underpants, warm socks, shoe warmer and muffler in the traffic control workers were significantly higher than the construction workers. The subjective symptoms in winter complained most frequently were shoulder stiffness (51.0%), finger cold sensation (50.0%) and neck stiffness (48.0%) in the traffic control workers, and were easy to get fatigued (49.0%), lumbago (48.3%) and finger cold sensation (47.7%) in the construction workers. On the basis of the results obtained, it is clearly shown that the two groups are at the risk of disorders due to their working environment. Therefore, these workers are needed to undergo occupational health programs for prevention of cold exposure disorders. Applications of preventive countermeasures for both groups are discussed. PMID:19531914

Inaba, Ryoichi; Kurokawa, Junichi; Mirbod, Seyed Mohammad

2009-07-01

116

Effect of simulated fall heat waves on cold hardiness and winter survival of hemlock looper, Lambdina fiscellaria (Lepidoptera: Geometridae).  

PubMed

The hemlock looper (Lambdina fiscellaria) is an important pest of eastern Canadian forests. The ongoing climate warming could modify the seasonal ecology of this univoltine species that lays eggs at the end of summer and overwinters at this stage. Indeed, the increase in frequency and intensity of extreme climatic events such as fall heat waves could interfere with the winter metabolism of the hemlock looper. Moreover, the host plant quality, which influences the quantity of insect energetic reserves, the geographic origin of populations and the conditions prevailing during the cold acclimation period, could cause various responses of this pest to climate warming. The main objective of this study is to determine the impact of these factors on hemlock looper winter biology. In October 2010, hemlock looper eggs initially collected from two geographic areas in the province of Québec, and from parents reared on two host plants, were exposed to fall heat waves of different intensities during 5 consecutive days. Supercooling points and cryoprotectant levels were measured on eggs on four different dates in 2010-2011 and survival rate was measured in April 2011. Our results show that hemlock looper eggs have a very low supercooling point and high levels of trehalose, glucose and mannitol in September and November. However, there is no clear relationship between the concentration of these compounds and the decrease in supercooling points. Contents in trehalose, glucose and mannitol were significantly influenced by fall heat waves and by the origin of the population. Winter survival of eggs from the temperate population was negatively affected by strong heat waves while the boreal population was not affected. This study suggests that the metabolism and winter survival of temperate hemlock looper populations in Québec will be more affected by fall heat waves that will increase in frequency due to climate change, than boreal populations. PMID:25585353

Vallières, Rosemarie; Rochefort, Sophie; Berthiaume, Richard; Hébert, Christian; Bauce, Éric

2015-02-01

117

Lower Stratospheric Temperature Differences Between Meteorological Analyses in two cold Arctic Winters and their Impact on Polar Processing Studies  

NASA Technical Reports Server (NTRS)

A quantitative intercomparison of six meteorological analyses is presented for the cold 1999-2000 and 1995-1996 Arctic winters. The impacts of using different analyzed temperatures in calculations of polar stratospheric cloud (PSC) formation potential, and of different winds in idealized trajectory-based temperature histories, are substantial. The area with temperatures below a PSC formation threshold commonly varies by approximately 25% among the analyses, with differences of over 50% at some times/locations. Freie University at Berlin analyses are often colder than others at T is less than or approximately 205 K. Biases between analyses vary from year to year; in January 2000. U.K. Met Office analyses were coldest and National Centers for Environmental Prediction (NCEP) analyses warmest. while NCEP analyses were usually coldest in 1995-1996 and Met Office or NCEP[National Center for Atmospheric Research Reanalysis (REAN) warmest. European Centre for Medium Range Weather Forecasting (ECMWF) temperatures agreed better with other analyses in 1999-2000, after improvements in the assimilation model. than in 1995-1996. Case-studies of temperature histories show substantial differences using Met Office, NCEP, REAN and NASA Data Assimilation Office (DAO) analyses. In January 2000 (when a large cold region was centered in the polar vortex), qualitatively similar results were obtained for all analyses. However, in February 2000 (a much warmer period) and in January and February 1996 (comparably cold to January 2000 but with large cold regions near the polar vortex edge), distributions of "potential PSC lifetimes" and total time spent below a PSC formation threshold varied significantly among the analyses. Largest peaks in "PSC lifetime" distributions in January 2000 were at 4-6 and 11-14 days. while in the 1996 periods, they were at 1-3 days. Thus different meteorological conditions in comparably cold winters had a large impact on expectations for PSC formation and on the discrepancies between different meteorological analyses. Met Office. NCEP, REAN, ECMWF and DAO analyses are commonly used for trajectory calculations and in chemical transport models; the choice of which analysis to use can strongly influence the results of such studies.

Manney, Gloria L.; Sabutis, Joseph L.; Pawson, Steven; Santee, Michelle L.; Naujokat, Barbara; Swinbank, Richard; Gelman, Melvyn E.; Ebisuzaki, Wesley; Atlas, Robert (Technical Monitor)

2001-01-01

118

Subtidal water flux through a multiple-inlet system: Observations before and during a cold front event and numerical experiments  

NASA Astrophysics Data System (ADS)

This paper examines the net transport through a multiple-inlet bay under a combined force of strong wind and tide, with observations and a model experiment. The observations were made in central Georgia in Sapelo and Altamaha Sounds between 13 and 17 September 2000. Wind was weak in the beginning of the survey. An air pressure trough (as a weak cold front) passed the area on 16 September, when the wind changed to the northeast and increased in magnitude. This front was associated with a midlatitude cyclone in the New England area. This weather event with an episode of strong northeasterly winds prompted a numerical model experiment on an idealized three-inlet bay, with a set of nonlinear 2-D shallow water equations on an f plane, which provides some insight to the wind-driven circulation under the presence of tidal forcing. It is found that tidally induced currents are small compared to wind-induced flows. When the wind direction is not perpendicular to the alignment of the three inlets, the net outward flow tends to occur at the inlet farther away in the downwind direction. This is associated with a net inward transport in the inlet opposite of the downwind direction. As a result, the middle inlet has the minimum of the net flow. When the wind is perpendicular to the barrier islands, and if the three inlets have different maximum depth values, the deeper inlet tends to have a net flow against the wind, while the shallower inlet tends to have a net flow in the direction of the wind. Offshore (onshore) currents may develop outside of the inlet with outward (inward) flow, as an effect of fluxes through the inlets on the coastal ocean.

Li, Chunyan

2013-04-01

119

Dominant black-capped chickadees pay no maintenance energy costs for their wintering status and are not better at enduring cold than subordinate individuals.  

PubMed

Winter requires physiological adjustments in northern resident passerines. Cold acclimatization is generally associated with an increase in physiological maintenance costs, measured as basal metabolic rate (BMR), and cold endurance, reflected by summit metabolic rate (M(sum)). However, several northern species also form social groups in winter and a bird's hierarchical position may influence the size of its metabolically active organs as well as its BMR. Winter metabolic performance in these species may therefore reflect a complex set of adjustments to both seasonal climatic variations and social environment. We studied the effect of social status on parameters of cold acclimatization (body mass, size of fat reserves and pectoral muscles, BMR and M(sum)) in free-living black-capped chickadees (Poecile atricapillus). Birds that were structurally large and heavy for their body size, mostly dominant individuals, carried more fat reserves and had larger pectoral muscles. However, social status had little effect on metabolic performance in the cold. Indeed, M(sum) was independent of social rank while mass-corrected BMR was slightly lower in dominant individuals, likely due to a statistical dilution effect caused by large metabolically inactive fat reserves. BMR and M(sum), whether considered in terms of whole-animal values, corrected for body mass or body size were nevertheless correlated, suggesting a functional link between these metabolic components. Our results therefore indicate that the energy cost of social dominance is not a generalized phenomenon in small wintering birds. PMID:22037961

Lewden, Agnès; Petit, Magali; Vézina, François

2012-04-01

120

Evaluating the role of fronts in habitat overlaps between cold and warm water species in the western North Pacific: A proof of concept  

NASA Astrophysics Data System (ADS)

Cold- and warm-water species' fishing grounds show a spatial synchrony around fronts in the western North Pacific (WNP). However, it is not yet clear whether a front (thermal, salinity or chlorophyll) acts as an absolute barrier to fish migration on either side or its structure allows interaction of species with different physiological requirements. Our objective was to assess potential areas of overlap between cold- and warm-water species using probabilities of presence derived from fishery datasets and remotely sensed environment data in the Kuroshio-Oyashio region in the WNP. Fishery data comprised skipjack tuna (Katsuwonus pelamis) fishing locations and proxy presences (derived from fishing night light images) for neon flying squid (Ommastrephes bartrami) and Pacific saury (Cololabis saira). Monthly (August-November) satellite remotely sensed sea-surface temperature, chlorophyll-a and sea-surface height anomaly images were used as environment data. Maximum entropy (MaxEnt) models were used to determine probabilities of presence (PoP) for each set of fishery and environment data for the area 35-45°N and 140-160°E. Maps of both sets of PoPs were compared and areas of overlap identified using a combined probability map. Results indicated that areas of spatial overlap existed among the species habitats, which gradually widened from September to November. The reasons for these overlaps include the presence of strong thermal/ocean-color gradients between cold Oyashio and warm Kuroshio waters, and also the presence of the sub-arctic front. Due to the high abundance of food along frontal zones, the species use the fronts as foraging grounds while confining within physiologically tolerable waters on either side of the front. The interaction zone around the front points to areas that might be accessible to both species for foraging, which suggests intense prey-predator interaction zones.

Mugo, Robinson M.; Saitoh, Sei-Ichi; Takahashi, Fumihiro; Nihira, Akira; Kuroyama, Tadaaki

2014-09-01

121

LIVE - Life in Vicious Environments: Mergers, shocks and cold fronts in super-cluster members A1750, A3558, and A1644.  

NASA Astrophysics Data System (ADS)

Understanding cluster mergers is imperative to our understanding of cluster formation. Our current understanding of the physics involved in mergers is poor because of the high resolution needed for such simulations and the lack of observational data. One of the most startling revelations of Chandra was the existence of cold fronts, the absence of strong shocks and lack of directly detected weak shocks. With its superior PSF Chandra is the best suited instrument for detecting sharp surface brightness and temperature discontinuities associated with shocks and cold fronts and making the necessary measurements to constrain the physical processes involved. We propose deep Chandra observations of the merging clusters A1750, A3558, and A1644.

Hudson, Daniel

2006-09-01

122

Coping with the cold: an ecological context for the abundance and distribution of rock sandpipers during winter in upper Cook Inlet, Alaska  

USGS Publications Warehouse

Shorebirds are conspicuous and abundant at high northern latitudes during spring and summer, but as seasonal conditions deteriorate, few remain during winter. To the best of our knowledge, Cook Inlet, Alaska (60.6? N, 151.6? W), is the world’s coldest site that regularly supports wintering populations of shorebirds, and it is also the most northerly nonbreeding location for shorebirds in the Pacific Basin. During the winters of 1997–2012, we conducted aerial surveys of upper Cook Inlet to document the spatial and temporal distribution and number of Rock Sandpipers (Calidris ptilocnemis) using the inlet. The average survey total was 8191 ± 6143 SD birds, and the average of each winter season’s highest single-day count was 13 603 ± 4948 SD birds. We detected only Rock Sandpipers during our surveys, essentially all of which were individuals of the nominate subspecies (C. p. ptilocnemis). Survey totals in some winters closely matched the population estimate for this subspecies, demonstrating the region’s importance as a nonbreeding resource to the subspecies. Birds were most often found at only a handful of sites in upper Cook Inlet, but shifted their distribution to more southerly locations in the inlet during periods of extreme cold. Two environmental factors allow Rock Sandpipers to inhabit Cook Inlet during winter: 1) an abundant bivalve (Macoma balthica) food source and 2) current and tidal dynamics that keep foraging substrates accessible during all but extreme periods of cold and ice accretion. C. p. ptilocnemis is a subspecies of high conservation concern for which annual winter surveys may serve as a relatively inexpensive population-monitoring tool that will also provide insight into adaptations that allow these birds to exploit high-latitude environments in winter.

Ruthrauff, Daniel R.; Gill, Robert E., Jr.; Tibbitts, T. Lee

2013-01-01

123

How Much can we Learn from a Merging Cold Front Cluster? Insights from X-Ray Temperature and Radio Maps of A3667  

NASA Astrophysics Data System (ADS)

The galaxy cluster A3667 is an ideal laboratory to study the plasma processes in the intracluster medium. High-resolution Chandra X-ray observations show a cold front in A3667. At radio wavelengths, A3667 reveals a double radio-relic feature in the outskirts of the cluster. These suggest multiple merger events in this cluster. In this paper, we analyze the substantial archival X-ray observations of A3667 from the Chandra X-ray Observatory and compare these with existing radio observations as well as state-of-the-art adaptive mesh refinement MHD cosmological simulations using Enzo. We have used two temperature map making techniques, weighted Voronoi tessellation and adaptive circular binning, to produce the high-resolution and largest field-of-view temperature maps of A3667. These high-fidelity temperature maps allow us to study the X-ray shocks in the cluster using a new two-dimensional shock-finding algorithm. We have also estimated the Mach numbers from the shocks inferred from previous ATCA radio observations. The combined shock statistics from the X-ray and radio data are in agreement with the shock statistics in a simulated MHD cluster. We have also studied the profiles of the thermodynamic properties across the cold front using ~447 ks from the combined Chandra observations on A3667. Our results show that the stability of the cold front in A3667 can be attributed to the suppression of the thermal conduction across the cold front by a factor of ~100-700 compared to the classical Spitzer value.

Datta, Abhirup; Schenck, David E.; Burns, Jack O.; Skillman, Samuel W.; Hallman, Eric J.

2014-10-01

124

2012/13 abnormal cold winter in Japan associated with Large-scale Atmospheric Circulation and Local Sea Surface Temperature over the Sea of Japan  

NASA Astrophysics Data System (ADS)

On Japan, wintertime cold wave has social, economic, psychological and political impacts because of the lack of atomic power stations in the era of post Fukushima world. The colder winter is the more electricity is needed. Wintertime weather of Japan and its prediction has come under the world spotlight. The winter of 2012/13 in Japan was abnormally cold, and such a cold winter has persisted for 3 years. Wintertime climate of Japan is governed by some dominant modes of the large-scale atmospheric circulations. Yasunaka and Hanawa (2008) demonstrated that the two dominant modes - Arctic Oscillation (AO) and Western Pacific (WP) pattern - account for about 65% of the interannual variation of the wintertime mean surface air temperature of Japan. A negative AO brings about cold winter in Japan. In addition, a negative WP also brings about cold winter in Japan. Looking back to the winter of 2012/13, both the negative AO and negative WP continued from October through December. If the previous studies were correct, it would have been extremely very cold from October through December. In fact, in December, in accordance with previous studies, it was colder than normal. Contrary to the expectation, in October and November, it was, however, warmer than normal. This discrepancy signifies that an additional hidden circumstance that heats Japan overwhelms these large-scale atmospheric circulations that cool Japan. In this study, we therefore seek an additional cause of wintertime climate of Japan particularly focusing 2012 as well as the AO and WP. We found that anomalously warm oceanic temperature surrounding Japan overwhelmed influences of the AO or WP. Unlike the inland climate, the island climate can be strongly influenced by surrounding ocean temperature, suggesting that large-scale atmospheric patterns alone do not determine the climate of islands. (a) Time series of a 5-day running mean AO index (blue) as defined by Ogi et al., (2004), who called it the SVNAM index. For reference, the conventional AO index is shown by the gray line. (b) a 5-day running mean WP index, (c) area-averaged Surface Air Temperature anomalies in Japan, (d) Air Temperature anomalies, (e) heat flux anomalies, and (f) Sea Surface Temperature anomalies. The boxed area on the Sea of Japan indicates the area in which the (d)-(f) indexes were calculated.

Ando, Y.; Ogi, M.; Tachibana, Y.

2013-12-01

125

Cold priming drives the sub-cellular antioxidant systems to protect photosynthetic electron transport against subsequent low temperature stress in winter wheat.  

PubMed

Low temperature seriously depresses the growth of wheat through inhibition of photosynthesis, while earlier cold priming may enhance the tolerance of plants to subsequent low temperature stress. Here, winter wheat plants were firstly cold primed (5.2 °C lower temperature than the ambient temperature, viz., 10.0 °C) at the Zadoks growth stage 28 (i.e. re-greening stage, starting on 20th of March) for 7 d, and after 14 d of recovery the plants were subsequently subjected to a 5 d low temperature stress (8.4 °C lower than the ambient temperature, viz., 14.1 °C) at the Zadoks growth stage 31 (i.e. jointing stage, starting on 8th April). Compared to the non-primed plants, the cold-primed plants possessed more effective oxygen scavenging systems in chloroplasts and mitochondria as exemplified by the increased activities of SOD, APX and CAT, resulting in a better maintenance in homeostasis of ROS production. The trapped energy flux (TRO/CSO) and electron transport (ETO/CSO) in the photosynthetic apparatus were found functioning well in the cold-primed plants leading to higher photosynthetic rate during the subsequent low temperature stress. Collectively, the results indicate that cold priming activated the sub-cellular antioxidant systems, depressing the oxidative burst in photosynthetic apparatus, hereby enhanced the tolerance to subsequent low temperature stress in winter wheat plants. PMID:24887010

Li, Xiangnan; Cai, Jian; Liu, Fulai; Dai, Tingbo; Cao, Weixing; Jiang, Dong

2014-09-01

126

Organic and inorganic aerosol compositions in Ulaanbaatar, Mongolia, during the cold winter of 2007 to 2008: Dicarboxylic acids, ketocarboxylic acids, and alpha-dicarbonyls  

Microsoft Academic Search

To investigate the distributions and sources of water-soluble organic acids in the Mongolian atmosphere, aerosol samples (PM2.5, n = 34) were collected at an urban site (47.92°N, 106.90°E, ˜1300 m above sea level) in Ulaanbaatar, the capital of Mongolia, during the cold winter. The samples were analyzed for water-soluble dicarboxylic acids (C2-C12) and related compounds (ketocarboxylic acids and alpha-dicarbonyls), as

Jinsang Jung; Batmunkh Tsatsral; Young J. Kim; Kimitaka Kawamura

2010-01-01

127

Organic and inorganic aerosol compositions in Ulaanbaatar, Mongolia, during the cold winter of 2007 to 2008: Dicarboxylic acids, ketocarboxylic acids, and ?-dicarbonyls  

Microsoft Academic Search

To investigate the distributions and sources of water-soluble organic acids in the Mongolian atmosphere, aerosol samples (PM2.5, n = 34) were collected at an urban site (47.92°N, 106.90°E, ?1300 m above sea level) in Ulaanbaatar, the capital of Mongolia, during the cold winter. The samples were analyzed for water-soluble dicarboxylic acids (C2–C12) and related compounds (ketocarboxylic acids and ?-dicarbonyls), as

Jinsang Jung; Batmunkh Tsatsral; Young J. Kim; Kimitaka Kawamura

2010-01-01

128

Effect of Cold Hardening on Sensitivity of Winter and Spring Wheat Leaves to Short-Term Photoinhibition and Recovery of Photosynthesis 1  

PubMed Central

Photoinhibition of photosynthesis and its recovery were studied in wheat (Triticum aestivum L.) leaves grown at nonhardening (20°C) and cold-hardening (5°C) temperatures. Cold-hardened wheat leaves were less susceptible to photoinhibition at 5°C than nonhardened leaves, and the winter cultivars, Kharkov and Monopol, were less susceptible than the spring cultivar, Glenlea. The presence of chloramphenicol, a chloroplastic protein synthesis inhibitor, increased the susceptibility to photoinhibition, but cold-hardened leaves still remained less susceptible to photoinhibition than nonhardened leaves. Recovery at 50 ?mol m?2 s?1 photosynthetic photon flux density and 20°C was at least biphasic, with a fast and a slow phase in all cultivars. Cold-hardened leaves recovered maximum fluorescence and maximum variable fluorescence in the dark-adapted state during the fast phase at a rate of 42% h?1 compared with 22% h?1 for nonhardened leaves. The slow phase occurred at similar rates (2% h?1) in cold-hardened and nonhardened leaves. Full recovery required up to 30 h. Fast-recovery phase was not reduced by either lowering the recovery temperature to 5°C or by the presence of chloramphenicol. Slow-recovery phase was inhibited by both treatments. Hence, the fast phase of recovery does not require de novo chloroplast protein synthesis. In addition, only approximately 60% of the photochemical efficiency lost through photoinhibition at 5°C was associated with lost [14C]atrazine binding and, hence, with damage to the secondary quinone electron acceptor for photosystem II-binding site. We conclude that the decrease in susceptibility to photoinhibition exhibited following cold hardening of winter and spring cultivars is not due to an increased capacity for repair of photoinhibitory damage at 5°C but reflects intrinsic properties of the cold-hardened photosynthetic apparatus. A model to account for the fast component of recovery is discussed. PMID:16653118

Hurry, Vaughan M.; Huner, Norman P. A.

1992-01-01

129

Dynamics and ecological consequences of avian influenza virus infection in greater white-fronted geese in their winter staging areas  

Microsoft Academic Search

Recent outbreaks of highly pathogenic avian influenza (HPAI) in poultry have raised interest in the interplay between avian influenza (AI) viruses and their wild hosts. Studies linking virus ecology to host ecology are still scarce, particularly for non-duck species. Here, we link capture–resighting data of greater white-fronted geese Anser albifrons albifrons with the AI virus infection data collected during capture

D. Kleijn; V. J. Munster; B. S. Ebbinge; D. A. Jonkers; G. J. D. M. Müskens; Y. Van Randen; R. A. M. Fouchier

2010-01-01

130

Effect of Severe Winter Cold on the Photosynthetic Potentials of Three Co-occurring Evergreen Woody Species in a Mediterranean Forest, Catalonia (Spain)  

NASA Astrophysics Data System (ADS)

Evergreen tree species in the Mediterranean region have to cope with a wide range of environmental stress conditions from summer drought to winter cold. The winter period can lead to photoinhibition due to a combination of high solar irradiances and chilling temperatures which can reduce the light saturation point. However, Mediterranean winter mildness can lead periodically to favourable environmental conditions above the threshold for positive carbon balance benefitting evergreen woody species in contrast to winter deciduous species. The advantage of being able to photosynthesis all year round with a significant fraction in the winter month is compensating for the lower photosynthetic potentials during spring and summer in comparison to deciduous species. In this work, we investigated the physiological behaviour of three evergreen tree species (Quercus ilex, Pinus halepensis, Arbutus undeo) co-occurring in a natural and mature Mediterranean forest after a period of mild winter conditions and their response to a sudden period of intense cold weather. Therefore, we examined in each period the photosynthetic potentials by estimating the maximum carboxylation rate (Vcmax) and the maximum electron transport rate (Jmax) through gas exchange measurements. The results indicate that all species exhibited extraordinary high photosynthetic potentials during the first period of measurement as a response to the mild conditions. However, the sudden cold period affected negatively the photosynthetic potentials of Quercus ilex and A. unedo with reduction ranging between 37 to 45 %, whereas they were observed to be only insignificantly reduced in Pinus halepensis. Our results can be explained by previous classifications into photoinhibition-avoiding (P. halpensis) and photoinhibition-tolerant (Q. ilex, A. undeo) species on the basis of their susceptibility to dynamic photoinhibition (Martinez Ferri 2000). Photoinhibition tolerant species are characterised with a more dynamic photoinhibition which is associated with fast reversible mechanisms. In contrast, photoinhibition-avoiding species are able to maintain a sustained PS II photochemical efficiency. In conclusion, our results provide new information on the photosynthetic responses of co-occurring Mediterranean evergreen tree species in a natural environment to contrasting winter conditions.

Sperlich, Dominik; Gracia, Carlos; Peñuelas, Josep; Sabaté, Santi

2013-04-01

131

Winter Weather Emergencies  

MedlinePLUS

Severe winter weather can lead to health and safety challenges. You may have to cope with Cold related health problems, including ... there are no guarantees of safety during winter weather emergencies, you can take actions to protect yourself. ...

132

Cold-front driven storm erosion and overwash in the central part of the Isles Dernieres, a Louisiana barrier-island arc  

USGS Publications Warehouse

Tropical and extratropical storms produce significant erosion on the barrier islands of Louisiana. Over the past 100 years, such storms have produced at least 2 km of northward beach-face retreat and the loss of 63% of the surface area of the Isles Dernieres, a low-lying barrier-island arc along the central Louisiana coast. Elevations on the islands within the arc are typically less than 2 m above mean sea level. The islands typically have a washover-flat topography with occasional, poorly developed, dune-terrace topography consisting of low-lying and broken dunes. The central part of the arc consists of salt-marsh deposits overlain by washover sands along the Gulf of Mexico shoreline. Sand thicknesses range from zero behind the beach, to less than 2 m under the berm crest, and back to zero in the first nearshore trough. The sand veneer is sufficiently thin that storms can strip all the sand from the beach face, exposing the underlying marsh deposits. The geomorphic changes produced by cold fronts, a type of extratropical storm that commonly affect the Isles Dernieres between late fall and early spring are described. Between August 1986 and September 1987, repeated surveys along eleven shore-normal transects that covered 400 m of shoreline revealed the timing and extent of cold-front-produced beach change along a typical section of the central Isles Dernieres. During the study period, the beach face retreated approximately 20 m during the cold-front season but did not rebuild during the subsequent summer. Because the volume of sand deposited on the backshore (5600 m3) was less than the volume of material lost from the beach face (19,200 m3), approximately 13,600 m3 of material disappeared. Assuming that underlying marsh deposits decrease in volume in direct proportion to the amount of beach-face retreat, an estimate of the mud loss during the study period is 14,000 m3. Thus, the decrease in volume along the profiles can be accounted for without removing any sand from the area, suggesting that a major effect of cold fronts is first to strip the sand from the beach face and then to erode the underlying marsh deposits. After being eroded, the mud is lost from the islands because currents transport it away from the islands. ?? 1990.

Dingler, J.R.; Reiss, T.E.

1990-01-01

133

Organic and inorganic aerosol compositions in Ulaanbaatar, Mongolia, during the cold winter of 2007 to 2008: Dicarboxylic acids, ketocarboxylic acids, and ?-dicarbonyls  

NASA Astrophysics Data System (ADS)

To investigate the distributions and sources of water-soluble organic acids in the Mongolian atmosphere, aerosol samples (PM2.5, n = 34) were collected at an urban site (47.92°N, 106.90°E, ˜1300 m above sea level) in Ulaanbaatar, the capital of Mongolia, during the cold winter. The samples were analyzed for water-soluble dicarboxylic acids (C2-C12) and related compounds (ketocarboxylic acids and ?-dicarbonyls), as well as organic carbon (OC), elemental carbon, water-soluble OC, and inorganic ions. Distributions of dicarboxylic acids and related compounds were characterized by a predominance of terephthalic acid (tPh; 130 ± 51 ng m-3, 19% of total detected organic acids) followed by oxalic (107 ± 28 ng m-3, 15%), succinic (63 ± 20 ng m-3, 9%), glyoxylic (55 ± 18 ng m-3, 8%), and phthalic (54 ± 27 ng m-3, 8%) acids. Predominance of terephthalic acid, which has not been reported previously in atmospheric aerosols, was mainly due to uncontrolled burning of plastic bottles and bags in home stoves for heating and waste incineration during the cold winter. This study demonstrated that most of the air pollutants were directly emitted from local sources such as heat and power plants, home stoves, and automobiles. Development of an inversion layer (<700 m above ground level) over the basin of Ulaanbaatar accelerated the accumulation of pollutants, causing severe haze episodes during the winter season.

Jung, Jinsang; Tsatsral, Batmunkh; Kim, Young J.; Kawamura, Kimitaka

2010-11-01

134

Winter storm impacts on chenier plain coast of southwestern Louisiana  

SciTech Connect

Stormy conditions associated with periodic winter cold front passages are closely related to transport of suspended sediment to the continental shelf, coastal erosion, and coastal progradation along shoreline sectors where abundant fine-grained sediments are stored on the inner shelf. Cold front passages occur between October and April on 3 to 5-day cycles. Their typical northwest to southeast direction of approach, large spatial scales, and numerous yearly occurrences (20-30 cycles/year) drive physical processes that cause significant coastal change. Acquisition of both remotely sensed multispectral and high-quality photographic data, collected from altitudes of 1,500, 9,000, and 21,000 m before and after cold front passages, forms a database for evaluating coastal change and suspended sediment transport pathways. Satellite imagery provide a longer term perspective on coastal change. Remotely sensed data sets are augmented with ground truth measurements of coastal configuration, sedimentological framework, and water quality.

Roberts, H.H.; Huh, O.K.; Hsue, S.A.; Rouse, L.J. Jr. (Louisiana State Univ., Baton Rouge (USA)); Rickman, D.A. (Stennis Space Center, Bay St. Louis, MS (USA))

1989-09-01

135

Impact of assimilating CO2 observations from a mountaintop site in the eastern United States on regional carbon fluxes during cold fronts and fair weather days  

NASA Astrophysics Data System (ADS)

Measurements of atmospheric CO2 are vital to estimating regional and continental CO2 sources and sinks. CarbonTracker, an inverse model developed by the NOAA Earth System Research Laboratory, assimilates observations from a network of CO2 mole fraction monitoring stations that each represent footprints generally larger than flux towers. Although CO2 measurements from mountaintop sites can provide important constraints on retrieved CO2 fluxes, they have only recently been integrated into the CarbonTracker system. The effect of assimilating such measurements on model performance is currently not well-known. In the present study, we investigate the effects of assimilating data from Pinnacles, a new mountaintop CO2 monitoring site in the eastern United States, on regional CO2 fluxes in CarbonTracker. We run the model for two one-month periods (December, 2008, and July, 2009) to investigate the sensitivity of CarbonTracker's global inversion system to CO2 mixing ratio measurements assimilated from Pinnacles during cold fronts and fair weather days, i.e. conditions when changes in CO2 due to frontal passage may be larger than changes due to flux from the biosphere. We find that CarbonTracker is more sensitive to the assimilation of Pinnacles CO2 measurements in July than in December. The assimilation of Pinnacles suggests greater CO2 uptake in the Midwest in July that occurs both during cold fronts and fair weather days.

Lee, T. R.; De Wekker, S.; Brooks, B.; Desai, A. R.; Andrews, A. E.

2011-12-01

136

Frontal passage and cold pool detection using Oklahoma Mesonet observations  

NASA Astrophysics Data System (ADS)

For over a dozen years the Oklahoma Mesonet network has provided surface observations at over 100 stations. These observations are used to analyze mass flux estimates from surface divergence, frontal passages, and cold pools, the latter defined herein as active regions where precipitation processes are creating near-surface cold air masses. Case studies are detailed and a 15-yr climatology of frontal passages and cold pools was computed in this research. Convergence, divergence, and precipitation are most strongly correlated in the summer months and least correlated in the winter months. Wet spring and summer days had the highest average convergence and divergence values while dry summer and fall days had the lowest average convergence and divergence. Frontal passages and cold pools are tracked throughout the Mesonet in various case studies, four of which are covered herein. The methodology is able to represent front location and cold pool areas quite well despite the low resolution of the Mesonet grid. The climatology of front and cold pool data yielded many similarities. Winter has the largest magnitude changes in DeltaT, DeltaP, and Deltah/cp while spring and fall had the largest magnitude change in Deltaqv. Summer has the lowest with the exception of spring DeltaT. Correlations between these variables are lowest in the more convectively active summer season. Convergence is roughly equal ahead of fronts from spring through fall; however, divergence is present in summer frontal passages earlier and stronger compared to the other seasons. Fronts and cold pools are most likely to occur in summer and spring with summer having the highest percentage of fronts which lead to cold pools. Fronts and cold pools are substantially more likely to occur during the late afternoon and early evening in the summer; other seasons had a slighter nocturnal increase in frequency. Western Oklahoma had higher frequencies of frontal passages and cold pools than Eastern Oklahoma with frontal passages having the stronger signal. These findings help identify seasonal, diurnal, and geographic distributions of fronts and cold pools and can be used in modeling studies to better the understanding of cold pool processes and parameterizations.

Lesage, Andrew T.

137

Effects of an early fall cold front on heat, phosphorus, silica, and manganese distributions in the hypolimnion of Lake Mendota, Wisconsin  

NASA Astrophysics Data System (ADS)

I examined the effects of an early fall (8-10 September 1977) cold front on eutrophic Lake Mendota, Wisconsin, during which 'Lake Number' LN (dimensionless) attained a minimum 3 h value of 0.45, and remained below 1.0 for a total of 39 h. The front accelerated heat transport downward through the main thermocline, resulting in hypolimnetic warming; the vertical eddy conductivity Kz increased monotonically with depth from a minimum 0.8 m 2 day -1 at 16 m to 1.9 m 2 day -1 at 21 m. The front also affected significant lateral and vertical redistribution of three passive solute 'tracers': phosphate (P), silicic acid (Si) and soluble reduced manganese (Mn 2+). Lateral concentration gradients along isopycnals predating the storm were erased. For Mn, especially, the vertical redistribution within the hypolimnion agreed with modeled changes based on vertical gradients and the Kz profile. Mn and P behaved quasi-conservatively within the anoxic hypolimnion (no net sources or sinks), but additional supplies of Si appeared in the hypolimnion (8.0 ± 1.5 mg m -3 day -1). This rate over 4 days agreed with the mean rate of hypolimnetic Si accumulation over the 80 day interval preceding 7 September 1977 (8.7 mg m -3 day -1). These results corroborate other environmental evidence that Mn and P both enter Lake Mendota's hypolimnion mainly during the first half of the summer, prior to the onset of bulk hypolimnetic anoxia, whereas Si is released by hypolimnetic sediments continuing into the late summer.

Stauffer, Robert E.

1993-10-01

138

Impacts of the North India Ocean SST on the extremely cold winters of 2011 and 2012 in the region of Da Hinggan Mountains and its western areas in China  

NASA Astrophysics Data System (ADS)

The study of the winter temperatures, averaged from the records of 11 observatories in the Da Hinggan Mountains and its western areas in China (DHM-WA), identified 11 extremely cold (? - 1.5 °C) and 13 extremely warm winters (? + 1.5 °C) during the past 60 years (1951-2010). The winters of 2011 and 2012 are another two extremely cold events. Aimed at exploring the climate causes, a comprehensive investigation is carried out on variations of some major atmospheric circulation components. Additionally, opposite circulation regimes are verified by examining the mean 500-hPa circulation patterns and sea level pressure (SLP) corresponding to 14 warm and 18 cold sea surface temperature (SST) phases over the North India Ocean (NIO) during the period of 1951-2010. Composite of an extremely cold winter usually includes a large and strong Siberian High, a deep East Asian trough to the west, an small and weak western Pacific Subtropical High to the east, a large North Polar vortex and a weakened westerly stream over Eurasia continent accompanied by a strong meridional winds from the polar region to lower latitude. Moreover, it has been found that a favorable circulation condition associated with the extremely cold winters to DHM-WA is mainly controlled by the SST over NIO in the previous warm season (June-September); This is primarily related to changes in the intensity of the Walker and Anti-Walker circulations, which subsequently influence the major circulation components and result in an extremely cold winter in DHM-WA.

Gao, Tao; Han, Jingwei; Gao, Lian; Yan, Wei

2014-08-01

139

The United Kingdom Environmental Change Network: Fronts  

NSDL National Science Digital Library

This resource briefly discusses what fronts are and how they form. Cold, warm, and occluded fronts are explained, and each one contains a section on how to recognize the fronts from weather changes shown on maps.

140

The January 2009 anomalous precipitation associated with the “Tail-end of the Cold Front” weather system in Northern and Eastern Mindanao (Philippines): Natural hazards, impacts and risk reductions  

Microsoft Academic Search

In the first half of January 2009, the southern Philippine island of Mindanao was overwhelmed by numerous natural disasters caused by the passage of the tail-end of the cold front. This otherwise ordinary weather condition was accompanied by unusually heavy precipitation sustained over a period of several days. This triggered numerous landslides and caused many drainage systems to swell, flooding

Decibel V. Faustino-Eslava; Graciano P. Yumul; Nathaniel T. Servando; Carla B. Dimalanta

2011-01-01

141

Is the decline of soil microbial biomass in late winter coupled to changes in the physical state of cold soils?  

Microsoft Academic Search

During winter when the active layer of Arctic and alpine soils is below 0 ? C, soil microbes are alive but metabolizingslowly,presumably incontact withunfrozenwater.Thisunfrozenwaterisatthe samenegative chemical potential as the ice. While both the hydrostatic and the osmotic components of the chemical potential will contribute to this negative value, we argue that the osmotic component (osmotic potential) is the significant contributor.

Robert L. Jefferies; N. Alan Walker; Kate A. Edwards; Jack Dainty

2009-01-01

142

Synergism of riverine and winter storm-related sediment transport processes in Louisiana's coastal wetlands  

SciTech Connect

The roles of various mechanisms that supply sediments from major sources, including rivers and the nearshore shelf, to coastal Louisiana are not well understood or quantified, temporally or spatially. Recent studies reveal that an important association between riverine sediment input and the cyclic passage of winter storms results in a periodic supply of suspended sediments to coastal marshlands. The fact that these two mechanisms coincide maximizes the availability of particulate matter for counteracting coastal land loss. Overbank sedimentation is one mechanism that supplies sediment from rivers to coastal wetlands. It occurs when stages exceed bankfull, most commonly in winter and spring. The timing of riverine sedimentation events is also related to suspended sediment concentrations and loads, which are also consistently greater during the winter and early spring months. During high discharge years, more sediment is available in winter than in other seasons, because at such times the sediment concentration and load maxima generally precede discharge maxima by several months. This period of maximum suspended sediment availability is coincident with the most severe winter storm activity, which elevates water levels near the coast and enhances suspended sediment transport to wetlands. Cold fronts also serve as a mechanism for suspended sediment transport, and qualitative observations suggest that during a typical cold-front passage onshore transport of suspended sediments is more likely. Prefrontal stages of winter cold-front passages along the Louisiana coast are characterized by prolonged periods of high wave action from the southerly quadrants, water level setup along the coast, and strong alongshore as well as onshore transport. At these times, suspended sediments from riverine input and the nearshore shelf are mobilized by the combination of riverine and cold front-related processes.

Mossa, J. (Geological Survey, Baton Rouge, LA (USA)); Roberts, H.H. (Louisiana State Univ., Baton Rouge (USA))

1990-09-01

143

Plasma membrane lipid alterations associated with cold acclimation of winter rye seedlings (Secale cereale L. cv Puma)  

SciTech Connect

Highly enriched plasma membrane fractions were isolated from leaves of nonacclimated (NA) and acclimated (ACC) rye (Secale cereale L. cv Puma) seedlings. Collectively, free sterols, steryl glucosides, and acylated steryl glucosides constituted > 50 mole % of the total lipid in both NA and ACC plasma membrane fractions. Glucocerebrosides containing hydroxy fatty acids constituted the major glycolipid class of the plasma membrane, accounting for 16 mole % of the total lipid. Phospholipids, primarily phosphatidylcholine and phosphatidylethanolamine with lesser amounts of phosphatidylglycerol, phosphatidic acid, phosphatidylserine, and phosphatidylinositol, comprised only 32 mole% of the total lipid in NA samples. Following cold acclimation, free sterols increased from 33 to 44 mole %, while steryl glucosides and acylated steryl glucosides decreased from 15 to 6 mole % and 4 to 1 mole %, respectively. Sterol analyses of these lipid classes demonstrated that free {beta}-sitosterol increased from 21 to 32 mole % (accounting for the increase in free sterols as a class) at the expense of sterol derivatives containing {beta}-sitosterol. Glucocerebrosides decreased from 16 to 7 mole % of the total lipid following cold acclimation. In addition, the relative proportions of associated hydroxy fatty acids, including 22:0 (h), 24:0 (h), 22:1 (h), and 24:1 (h) were altered. The phospholipid content of the plasma membrane fraction increased to 42 mole % of the total lipid following cold acclimation. Although the relative proportions of the individual phospholipids did not change appreciably after cold acclimation, there were substantial differences in the molecular species. Di-unsaturated molecular species of phosphatidylcholine and phosphatidylethanolamine increased following acclimation. These results demonstrate that cold acclimation results in substantial changes in the lipid composition of the plasma membrane.

Lynch, D.V.; Steponkus, P.L. (Cornell Univ., Ithaca, NY (USA))

1987-01-01

144

Effect of Cold Hardening on the Components of Respiratory Decarboxylation in the Light and in the Dark in Leaves of Winter Rye.  

PubMed Central

In the dark, all decarboxylation reactions are associated with the oxidase reactions of mitochondrial electron transport. In the light, photorespiration is also active in photosynthetic cells. In winter rye (Secale cereale L.), cold hardening resulted in a 2-fold increase in the rate of dark respiratory CO2 release from leaves compared with nonhardened (NH) controls. However, in the light, NH and cold-hardened (CH) leaves had comparable rates of oxidase decarboxylation and total intracellular decarboxylation. Furthermore, whereas CH leaves showed similar rates of total oxidase decarboxylation in the dark and light, NH leaves showed a 2-fold increase in total oxidase activity in the light compared with the dark. Light suppressed oxidase decarboxylation of end products of photosynthesis 2-fold in NH leaves and 3-fold in CH leaves in air. However, in high-CO2, light did not suppress the oxidase decarboxylation of end products. Thus, the decrease in oxidase decarboxylation of end products observed in the light and in air reflected glycolate-cycle-related inhibition of tricarboxylic acid cycle activity. We also showed that the glycolate cycle was involved in the decarboxylation of the end products of photosynthesis in both NH and CH leaves, suggesting a flow of fixed carbon out of the starch pool in the light. PMID:12226322

Hurry, V.; Keerberg, O.; Parnik, T.; Oquist, G.; Gardestrom, P.

1996-01-01

145

The effects of a mid-winter 8-week course of sub-sunburn sunbed exposures on tanning, vitamin D status and colds.  

PubMed

Like UV irradiation, which generates vitamin D(3) in the skin, the hormonally active metabolite, 1,25-dihydroxyvitamin D(3), boosts innate immunity against viruses and bacteria. Epidemiologic studies have found high vitamin D levels to be associated with lower risk of infections of the upper respiratory tract (colds). We have therefore performed an intervention study in 105 young adults (ages 18-30 years; 91% female) over a mid-winter 8-week period (January-March 2010). The participants were randomised to 3 groups: (A) subjected to 3 times a week sub-sunburn sunbed exposure (n = 35), (B) daily vitamin D supplementation, @ 1000 IU (n = 37), and (C) a control group without any intervention (n = 33). The mean serum level of 25-hydroxyvitamin D (25(OH)D) dropped from 62 to 55 nmol l(-1) in group C, while these levels rose from 62 to 109 and from 58 to 93 nmol l(-1) in groups A and B, respectively (p < 0.001). The skin on the chest darkened significantly in group A (mean difference in lightness, L*, equalled -5.7, p < 0.001), correlating significantly, but weakly, with increases in 25(OH)D (3.3 nmol l(-1) per unit drop in L*, R(2) = 0.17, p = 0.014). The percentage of self-reported colds with proper signs and symptoms was only slightly and not significantly reduced in groups A and B in comparison to group C: 57 and 51 versus 67%, respectively. Hence, the sub-sunburn sunbed treatment was effective in tanning and increasing the 25(OH)D serum level, more so than 1000 IU per day, but had no appreciable effect on colds. PMID:23104230

de Gruijl, Frank R; Pavel, Stan

2012-12-01

146

Organic carbon, biogenic silica and diatom fluxes in the marginal winter sea-ice zone and in the Polar Front Region: interannual variations and differences in composition  

NASA Astrophysics Data System (ADS)

Particle fluxes and composition were examined over 5 years at two mooring sites in the Polar Front Region (site PF: 50°09.S, 5°50.E) and in the marginal winter sea-ice zone (site BO: 54°30.S, 3°20.W) in the eastern Atlantic Sector of the Southern Ocean. Seasonality, interannual variability and the magnitude of total mass fluxes were higher at site BO compared to PF. Five-year averages and standard deviations (1 ?) of total mass fluxes were 19.6±18.5 and 24.8±29.9 g m -2 at PF and BO, respectively. Peak fluxes at site BO occurred in January 1995, but the highest peak was measured in February 1991 (almost 1300 mg m -2 d -1) followed by post-bloom sedimentation in March through May. This would imply a time shift of several months between the onset of sea-ice retreat in October and major sedimentation events recorded in January/February with the upper BO traps. At site PF, highest fluxes of about 500 mg m -2 d -1 were found between December and March. Blooms at site BO, influenced by sea ice as indicated by diatom species composition, seem to occur more sporadically (e.g., in 1991 and 1995). Annual diatom fluxes were 11.8×10 6 and 20×10 6 valves m -2 during the deployments PF3 (1990) and BO1 (1991), respectively. At PF3, Fragilariopsis kerguelensis (37%) and Thalassionema nitzschioides fo1 (26.5%) dominated diatom flux, while F. kerguelensis (29%) and sea-ice-related algae (40%) were the main contributors to total diatom flux at site BO. During deployment BO1, the bloom collected in February was characterized by a very high molar Si:C of 8.8 that decreased almost continuously during the post-bloom phase, reaching a value of 1 in May. This change, however, was not documented in diatom species composition. We obtained a significant linear increase of biogenic opal with organic carbon fluxes at site PF and a highly significant but exponential relationship at site BO. Higher annual total mass fluxes were recorded at site BO, primarily due to elevated opal and lithogenic fluxes, corresponding to a higher silicate availability in the southern Antarctic Circumpolar Current. In contrast, higher mean organic carbon fluxes were obtained at site PF in accordance with elevated primary production and biomass. We obtained a three-fold higher molar Si:C ratio (5-year mean) for sinking particles collected with the upper BO traps (Si:C=4.0) compared to the PF (Si:C=1.3), consistent with the general pattern of Si and Fe availability. In particular at site BO, the Si:C ratios were usually high, even when accounting for organic carbon decay and biogenic silica (BSi) dissolution in the upper water column. At this study site, the Si:C ratios increased with lithogenic fluxes.

Fischer, G.; Gersonde, R.; Wefer, G.

147

Bio-Optical Properties and Ocean Color Algorithms for Coastal Waters Influenced by the Mississippi River During a Cold Front Passage  

NASA Technical Reports Server (NTRS)

During the passage of a cold front in March 2002, bio-optical properties examined in coastal waters impacted by the Mississippi River indicated westward advective flows and increasing river discharge containing a larger nonalgal particle content contributed significantly to surface optical variability. A comparison of seasonal data from three cruises indicated spectral models of absorption and scattering to be generally consistent with other coastal environments, while their parameterization in terms of chlorophyll a concentration (Chl) showed seasonal variability. The exponential slope of the colored dissolved organic matter (CDOM) averaged 0.0161 plus or minus 0.00054 per nanometer, and for nonalgal absorption it averaged 0.011 per nanometer with deviations from general trends observed due to anomalous water properties. Although the phytoplankton specific absorption coefficients varied over a wide range (0.02 to 0.1 square meters (mg Chl) sup -1)) being higher in offshore surface waters, values of phytoplankton absorption spectra at the SeaWiFS wavebands were highly correlated to modeled values. The normalized scattering spectral shapes and the mean spectrum were in agreement to observations in other coastal waters, while the backscattering ratios were on average lower in phytoplankton dominated surface waters (0.0101 plus or minus 0.002) and higher in near-bottom waters (0.0191 plus or minus 0.0045) with low Chl. Average percent differences in remote sensing reflectance R (sub rs) derived form modeled and in-eater radiometric measurements were highest in the blue wavebands (52%) and at sampling stations with a ore stratified water column. Estimates of Chl and CDOM absorption derived from SeaWiFS images generated using regional empirical algorithms were highly correlated to in situ data.

D'Sa Eurico J.; Miller, Richard L.; DelCastillo, Carlos

2006-01-01

148

KELVIN-HELMHOLTZ INSTABILITIES AT THE SLOSHING COLD FRONTS IN THE VIRGO CLUSTER AS A MEASURE FOR THE EFFECTIVE INTRACLUSTER MEDIUM VISCOSITY  

SciTech Connect

Sloshing cold fronts (CFs) arise from minor merger triggered gas sloshing. Their detailed structure depends on the properties of the intracluster medium (ICM): hydrodynamical simulations predict the CFs to be distorted by Kelvin-Helmholtz instabilities (KHIs), but aligned magnetic fields, viscosity, or thermal conduction can suppress the KHIs. Thus, observing the detailed structure of sloshing CFs can be used to constrain these ICM properties. Both smooth and distorted sloshing CFs have been observed, indicating that the KHI is suppressed in some clusters, but not in all. Consequently, we need to address at least some sloshing clusters individually before drawing general conclusions about the ICM properties. We present the first detailed attempt to constrain the ICM properties in a specific cluster from the structure of its sloshing CF. Proximity and brightness make the Virgo Cluster an ideal target. We combine observations and Virgo-specific hydrodynamical sloshing simulations. Here, we focus on a Spitzer-like temperature-dependent viscosity as a mechanism to suppress the KHI, but discuss the alternative mechanisms in detail. We identify the CF at 90 kpc north and northeast of the Virgo center as the best location in the cluster to observe a possible KHI suppression. For viscosities {approx}> 10% of the Spitzer value KHIs at this CF are suppressed. We describe in detail the observable signatures at low and high viscosities, i.e., in the presence or the absence of KHIs. We find indications for a low ICM viscosity in archival XMM-Newton data and demonstrate the detectability of the predicted features in deep Chandra observations.

Roediger, E. [Hamburger Sternwarte, Universitaet Hamburg, Gojensbergsweg 112, D-21029 Hamburg (Germany)] [Hamburger Sternwarte, Universitaet Hamburg, Gojensbergsweg 112, D-21029 Hamburg (Germany); Kraft, R. P.; Forman, W. R.; Nulsen, P. E. J. [Harvard/Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)] [Harvard/Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Churazov, E., E-mail: eroediger@hs.uni-hamburg.de [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching (Germany)

2013-02-10

149

The effects of day and night temperatures during early growth of winter oilseed rape ( Brassica napus L. var. oleifera cv. Górcza?ski) seedlings on their morphology and cold acclimation responses  

Microsoft Academic Search

Studies on the effects of temperature during the early stage of growth on frost resistance of winter rape seedlings under\\u000a controlled conditions were performed. It was found that cold acclimation responses of plants were affected to a great extent\\u000a by the conditions of the seedlings early growth. During this period, when the day temperatures were reduced to the range from

Marcin Rapacz

1998-01-01

150

Exercising in Cold Weather  

MedlinePLUS

... www.nia.nih.gov/Go4Life Exercising in Cold Weather Exercise has benefits all year, even during winter. ... activities when it’s cold outside: l Check the weather forecast. If it’s very windy or cold, exercise ...

151

Seasonal, synoptic and diurnal variation of atmospheric water-isotopologues in the boundary layer of Southwestern Germany caused by plant transpiration, cold-front passages and dewfall.  

NASA Astrophysics Data System (ADS)

Atmospheric water is an enormously crucial trace gas. It is responsible for ~70 % of the natural greenhouse effect (Schmidt et al., JGR, 2010) and carries huge amounts of latent heat. The isotopic composition of water vapor is an elegant tracer for a better understanding and quantification of the extremely complex and variable hydrological cycle in Earth's atmosphere (evaporation, cloud condensation, rainout, re-evaporation, snow), which in turn is a prerequisite to improve climate modeling and predictions. As H216O, H218O and HDO differ in vapor pressure and mass, isotope fractionation occurs due to condensation, evaporation and diffusion processes. In contrast to that, plants are able to transpire water with almost no isotope fractionation. For that reason the ratio of isotopologue concentrations in the boundary layer (BL) provides, compared to humidity measurements alone, independent and additional constraints for quantifying the strength of evaporation and transpiration. Furthermore the isotope ratios contain information about transport history of an air mass and microphysical processes, that is not accessible by humidity measurements. Within the project MUSICA (MUlti-platform remote Sensing of Isotopologues for investigating the Cycle of Atmospheric water) a commercial Picarro Analyzer L2120-i is operated at Karlsruhe in Southwestern Germany, which is continuously measuring the isotopologues H216O, HDO and H218O of atmospheric water vapor since January 2012. A one year record of H216O, HDO and H218O shows clear seasonal, synoptic and diurnal characteristics and reveals the main driving processes affecting the isotopic composition of water vapor in the Middle European BL. Changes in continental plant transpiration and evaporation throughout the year lead to a slow seasonal HDO/H216O-variation, that cannot be explained by pure Rayleigh condensation. Furthermore, cold-front passages from NW lead to fast and pronounced depletion of the HDO/H216O-ratio within minutes. Superimposed to these variations are local diurnal processes like dewfall, which cause a diurnal pattern captured by the deuterium excess.

Christner, Emanuel; Dyroff, Christoph; Kohler, Martin; Zahn, Andreas; Gonzales, Yenny; Schneider, Matthias

2013-04-01

152

Severe Weather 101: Winter Weather Basics  

MedlinePLUS

... main types of precipitation are snow, sleet or freezing rain. Why can winter storms be so dangerous? ... to make a winter storm. Cold air. Below freezing temperatures in the clouds and near the ground ...

153

Winter Storms and Extreme Cold  

MedlinePLUS

... on their roads, vehicles must be equipped with chains or snow tires with studs. Update the emergency ... kit with pocket knife necessary medications blanket(s) tow chain or rope road salt and sand booster cables ...

154

Implementation of Cold-Cloud Processes in a Source-Oriented WRF/Chem Model to Study a Winter Storm in California  

NASA Astrophysics Data System (ADS)

Mineral dust particles commonly have a favorable arrangement of surface sites that allows them to serve as ice nuclei (IN). Secondary coatings that condense on mineral dust particles may reduce their ability to serve as IN. Both of these effects point to the importance of the particle mixing state when predicting cloud condensation nuclei (CCN) / IN concentrations. The source-oriented Weather Research and Forecasting chemistry model (SOWC) was modified to include cold cloud processes and applied to investigate how source-oriented aerosols influence cloud and ice formation and optical properties in the atmosphere. SOWC tracks 6-dimensional chemical variables (X, Z, Y, Size Bins, Source Types, Species) through an explicit simulation of atmospheric chemistry and physics. Particle radius and number concentration are conserved for each source type and size bin. Simulations in this study use 38 chemical species from 6 emission sources (wood smokes, gasoline, diesel, meat cooking, dust, and other aerosol types) and 8 size bins, spanning the particle diameter range from 0.01 to 10 microns. A new source-oriented hydrometeors module was implemented into the SOWC model to simulate microphysics processes with all source-oriented hydrometeors (cloud, ice, rain, snow and graupel) using the Morrison two-moment microphysics scheme. In our study, all aerosol source types can activate to form cloud droplets based on the Köhler theory, and dust is the only source of IN. We considered the impact of Asian dust on the ice formation in clouds over the Sierra Nevada mountain range during the CalWater field campaign (2011) and estimated dust contributions to total IN concentrations. Aerosols within hydrometeors alter the radiative properties of the cloud droplets. The Goddard shortwave and longwave radiation schemes were modified to interact with source-oriented aerosols and hydrometeors so that aerosol direct and indirect effects could be studied. Geometric-optics approach in the radiation schemes considered the chemistry components and the physical shape of ice crystal to more accurately calculate the atmospheric optical thickness, signal scattering albedo, and asymmetry factor. The enhanced SOWC model was implemented to study a winter storm event that occurred on February 16th, 2011, in California, and the results are compared to the measurements obtained during the CalWater field campaign.

Lee, H.; Chen, S.; Kleeman, M.

2013-12-01

155

Winter WeatherWinter WeatherWinter WeatherWinter Weather Tips to prepare your carTips to prepare your carTips to prepare your carTips to prepare your car  

E-print Network

Winter WeatherWinter WeatherWinter WeatherWinter Weather Tips to prepare your carTips to prepare your carTips to prepare your carTips to prepare your car for winterfor winterfor winterfor winter Charge it. Cold weather is tough on batteries. At zero degrees, a car's battery loses about 60 percent

Queitsch, Christine

156

What Maintains the SST Front North of the Eastern Pacific Equatorial Cold Tongue?* SIMON P. DE SZOEKE AND SHANG-PING XIE  

E-print Network

cool dry air is advected northward over warm SST. The surface heat flux is decomposed into a response radiation. Evaporation and net surface cooling are at a maximum just north of the SST front where relatively to SST alone, and an atmospheric feedback. The atmospheric feedback enhances cooling on the north side

157

Stationary fronts prolong bad weather  

NSDL National Science Digital Library

These simple animated GIF's are activated with cursor rollover and picture the standoff when neither the warm front nor the cold front is advancing. On a weather map the stationary front is marked by alternating triangles and half circles with the triangles pointing toward the warm air and the circles pointing toward the cooler air. The overriding of warm air on the cooler air can bring several days of cloudy, inclement weather. While the front appears to touch the ground the actual boundary between air masses can be thousands of feet aloft and hundreds of miles away.

John Herne

158

Fronts and frontogenesis as revealed by high time resolution data  

NASA Technical Reports Server (NTRS)

Upper air sounding are used to examine a cold front of average intensity. Vertical cross sections of potential temperature and wind, and horizontal analyses were compared and adjusted for consistency. These analyses were then used to study the evolution of the front, found to consist of a complex system of fronts occurring at all levels of the troposphere. Low level fronts were strongest at the surface and rapidly weakened with height. Fronts in the midddle troposphere were much more intense. The warm air ahead of the fronts was nearly barotropic, while the cold air behind was baroclinic through deep layers. A deep mixed layer was observed to grow in this cold air.

Frank, A. E.; Barber, D. A.

1977-01-01

159

Vernalization and epigenetics: how plants remember winter  

Microsoft Academic Search

One of the remarkable aspects of the promotion of flowering by vernalization is that plants have evolved the ability to measure a complete winter season of cold and to ‘remember’ this prior cold exposure in the spring. Recent work in Arabidopsis demonstrates the molecular basis of this memory of winter: vernalization causes changes in the chromatin structure of a flowering

Sibum Sung; Richard M Amasino

2004-01-01

160

Warm winter spells in the Swiss Alps: Strong heat waves in a cold season? A study focusing on climate observations at the Saentis high mountain site  

Microsoft Academic Search

Investigations conducted for several Swiss mountain climatological sites, and in particular the Saentis high mountain site at 2,500 m above sea level, show that positive temperature anomalies during the winter season currently exceed those of all other seasons. These ``heat waves'' exhibit daily maximum temperature anomalies sometimes in excess of 16°C, and are observed to have increased substantially since the

Martin Beniston

2005-01-01

161

PM10 modeling of Beijing in the winter  

NASA Astrophysics Data System (ADS)

The megacity of Beijing, China, has had an air pollution problem since the 1990s. The concentrations of particulate matter with an aerodynamic diameter less than 10 ?m (PM10) in Beijing in the winter of 2000 were high; the average value of 188 ?g m -3 was nearly four times the first grade national standard of 50 ?g m -3. The CALPUFF modeling system was used to simulate PM10 dispersion from 1 January 2000 to 29 February 2000. We used near real-time landcover data from the moderate resolution imaging spectroradiometer (MODIS). Statistical evaluation indicated that the model agreed well with the observations. The fluctuations of 24-h PM10 concentrations followed the winter synoptic winds. Cold air from the northwest or north intruded over Beijing for average periods of 4 days in winter, accompanied by high wind speeds. PM10 was swept out of Beijing after the cold fronts and accumulated again once the winds stopped, until the next cold air intrusion. Capital Steel Corporation Limited contributed 46% of the PM10 mass concentrations observed in the Shijingshan industrial area, and had little effect on the eastern part or the center of Beijing. The other industrial regions distributed in southeastern Beijing accounted for an average of 18% of the PM10 in Beijing. Boilers associated with coal consumption mostly for winter heating contributed 31%. Motor vehicles and road dust contributed 5% and 13%, respectively. The total of residential heating in old houses and restaurants contributed approximately 7%. The primary PM10 emissions from electrical generating units were relatively low. Some suggestions are proposed for reducing PM10 pollution in Beijing.

Song, Yu; Zhang, Minsi; Cai, Xuhui

162

The Barents Sea polar front and water masses variability (1980-2011)  

NASA Astrophysics Data System (ADS)

The polar front separates the warm and saline Atlantic Waters encountered in the western part of the Barents Sea from the cold and fresh Arctic Waters situated in the northern part. These water masses can mix together, mainly in the eastern part of the Barents Sea, generating dense waters in winter which can cascade into the Arctic Ocean to form the Artic Intermediate Waters. To study the interannual variability and evolution of these water masses and the fronts, we have merged data from the International Council for the Exploration of the Sea and the Arctic and Antarctic Research Institute and have built a new database which covers the period 1980-2011. The summer data is interpolated on a regular grid and a "Probability Density Function" method is used to show that the polar front splits into two branches east of 32° E where the topographic constraint weakens. Two fronts can then be defined: the "Northern Polar Front" is associated with strong salinity gradients and the "Southern Polar Front" with temperature gradients. They enclose the dense Barents Sea Water. The interannual variability of the water masses is apparent in the observed data and is linked to that of the ice cover. In contrast, the link with the Arctic Oscillation is not clear. However, results from a general circulation model suggest that such a link could be found if winter data were taken into account. A strong trend, which amplifies during the last decade, is also found: the Atlantic Water occupies a larger volume of the Barents Sea. This "Atlantification" could be accompanied by a northwards displacement of the southern polar front in the eastern part of the Barents Sea (which is suggested by a model based study) and a decrease of the volume occupied by the Arctic Waters.

Oziel, L.; Sirven, J.; Gascard, J.-C.

2015-03-01

163

Sea surface temperature fronts on the continental shelf off the southeast Brazil coast  

NASA Astrophysics Data System (ADS)

Seven years of sea surface temperature (SST) data derived from Moderate Resolution Imaging Spectroradiometer (MODIS) were used to detect the distribution and variability of fronts off the coast of Brazil. Frontal probabilities computed over the entire period indicate three regions with high activity located at 21oS, 22.5oS and 23oS. Most fronts are located on the shelf inshore of the 200 m isobath, and more persistent fronts are found in areas of steeper shelf slope. Off 21oS, fronts are mostly distributed at the shelfbreak along the 200 m isobath. Farther south at 22.5oS, fronts are concentrated along the 200 m isobath only in winter, being more evenly distributed on the shelf during the other seasons. At 23oS, in the lee of a major cape, fronts are found closer to the coast year-round. Frontal probabilities are higher during summer, presumably because of persistent upwelling favorable winds. Alongshore winds and SST are significantly correlated during summer, with coefficients ranging from 0.2 to 0.4. Preliminary results reveal a large influence of alongshore transport of upwelling water. Cold water at the surface is first found at 21oS, before being transported southward.

Wang, Y.; Castelao, R. M.

2012-12-01

164

Building a Weather-Ready Nation Winter Weather Safety  

E-print Network

Building a Weather-Ready Nation Winter Weather Safety NOAA/NWS Winter Weather Safety Seasonal Campaign www.weather.gov #12;Building a Weather-Ready Nation Winter Weather Hazards Winter Weather Safety www.weather.gov · Snow/Ice · Blizzards · Flooding · Cold Temperatures #12;Building a Weather

165

HISTORICAL PERSPECTIVE ESSAY Vernalization, Competence, and the Epigenetic Memory of Winter  

E-print Network

for exposure to the prolonged cold of winter to flower influences the plant's life history. Mono- carpic or winter annuals. The term biennial is often used for plants that have an obligate re- quirement for cold exposure to flower, and the term winter annual is often used for plants with a quantitative cold

Raines, Ronald T.

166

Rossby waves, extreme fronts, and wildfires in southeastern Australia  

NASA Astrophysics Data System (ADS)

The most catastrophic fires in recent history in southern Australia have been associated with extreme cold fronts. Here an extreme cold front is defined as one for which the maximum temperature at 2 m is at least 17°C lower on the day following the front. An anticyclone, which precedes the cold front, directs very dry northerlies or northwesterlies from the interior of the continent across the region. The passage of the cold front is followed by strong southerlies or southwesterlies. European Centre for Medium-Range Weather Forecasts ERA-Interim Reanalyses show that this regional synoptic pattern common to all strong cold fronts, and hence severe fire conditions, is a consequence of propagating Rossby waves, which grow to large amplitude and eventually irreversibly overturn. The process of overturning produces the low-level anticyclone and dry conditions over southern Australia, while simultaneously producing an upper level trough and often precipitation in northeastern Australia.

Reeder, Michael J.; Spengler, Thomas; Musgrave, Ruth

2015-03-01

167

Nutrition for winter sports.  

PubMed

Winter sports are played in cold conditions on ice or snow and often at moderate to high altitude. The most important nutritional challenges for winter sport athletes exposed to environmental extremes include increased energy expenditure, accelerated muscle and liver glycogen utilization, exacerbated fluid loss, and increased iron turnover. Winter sports, however, vary greatly regarding their nutritional requirements due to variable physiological and physique characteristics, energy and substrate demands, and environmental training and competition conditions. What most winter sport athletes have in common is a relatively lean physique and high-intensity training periods, thus they require greater energy and nutrient intakes, along with adequate food and fluid before, during, and after training. Event fuelling is most challenging for cross-country skiers competing in long events, ski jumpers aiming to reduce their body weight, and those winter sport athletes incurring repeated qualification rounds and heats. These athletes need to ensure carbohydrate availability throughout competition. Finally, winter sport athletes may benefit from dietary and sport supplements; however, attention should be paid to safety and efficacy if supplementation is considered. PMID:22150424

Meyer, Nanna L; Manore, Melinda M; Helle, Christine

2011-01-01

168

Winter Weather  

MedlinePLUS

... Matters What's New A - Z Index Disasters & Severe Weather Earthquakes Extreme Heat Floods Hurricanes Landslides Tornadoes Tsunamis Volcanoes Wildfires Winter Weather Winter Weather Language: English Español (Spanish) Recommend on Facebook Tweet ...

169

Winter Icing and Storms Project (WISP)  

Microsoft Academic Search

Field studies in support of the Winter Icing and Storms Project (WISP) were conducted in the Colorado Front Range area from 1 February to 31 March 1990(WISP90) and from 15 January to 5 April 1991 (WISP91). The main goals of the project are to study the processes leading to the formation and depletion of supercooled liquid water in winter storms

Roy Rasmussen; Marcia Politovich; John Marwitz; Wayne Sand; John McGinley; John Smart; Roger Pielke; Steve Rutledge; Doug Wesley; Greg Stossmeister; Ben Bernstein; Kim Elmore; Nick Powell; Ed Westwater; B. Boba Stankov; Don Burrows

1992-01-01

170

The January 2009 anomalous precipitation associated with the “Tail-end of the Cold Front” weather system in Northern and Eastern Mindanao (Philippines): Natural hazards, impacts and risk reductions  

NASA Astrophysics Data System (ADS)

In the first half of January 2009, the southern Philippine island of Mindanao was overwhelmed by numerous natural disasters caused by the passage of the tail-end of the cold front. This otherwise ordinary weather condition was accompanied by unusually heavy precipitation sustained over a period of several days. This triggered numerous landslides and caused many drainage systems to swell, flooding huge tracts of low lying areas that have not experienced similar events in the recent past. Many communities were caught unprepared for the calamity. The amount and extent of damage reflect both the magnitude of the natural disaster itself and the community's nominal level of disaster-preparedness. In view of the increasing atmospheric moisture levels and the likelihood that global warming will affect the weather patterns, there is a possibility that similar weather disturbances can become more frequent. Therefore, there is an urgent need for disaster risk management programs to be developed or enhanced at the local community level especially in areas most vulnerable to weather-related natural hazards, in light of changing global climatic patterns.

Faustino-Eslava, Decibel V.; Yumul, Graciano P., Jr.; Servando, Nathaniel T.; Dimalanta, Carla B.

2011-03-01

171

Atmospheric density remote sensing of mesosphere and thermosphere to be used for spacecraft design by adopting VHF radar and HF Doppler sounder at low latitude west Pacific site during winter time  

NASA Technical Reports Server (NTRS)

Simultaneous observations of VHF radar and HF Doppler array systems located at Chung Li (Taiwan) are used to observe three-dimensional wind speeds and gravity waves. The density perturbations are determined at different altitudes of the mesosphere and thermosphere during weak convective motions of the cold front in the winter. The present observations are believed to be valuable for space projects dealing with the low-latitude atmosphere.

Hung, R. J.; Tsao, Y. D.; Johnson, D. L.; Chen, A. J.; Lee, C. C.

1989-01-01

172

How Cold Is Cold?  

NSDL National Science Digital Library

Heat and cold are often difficult concepts for children to understand. First, our everyday sloppy language gives them a predisposition to such common misconceptions as cold being a substance that moves from place to place. Our colloquial language often re

Richard Konicek-Moran

2008-04-01

173

Winter Storms  

NSDL National Science Digital Library

This site offers general background about winter storms as well as interactive activities to teach visitors about these storms. It also offers a teacher's guide to using this site and links to other weather-related pages. There are four main topics: All About Winter Storms, Interactive Weather Maker, Interactive Winter Storm Timeline, and Ask Our Winter Storm Expert. All About Winter Storms gives general background information an a glossary of weather terms. The Weather Maker offers students a chance to control the weather through a simulation in which they affect the weather by changing variables such as humidity, equatorward temperature, and polarward temperature. The Storm Timeline offers students a chance to move up and down the timeline to learn about past winter storms. In Ask the Expert, students can email their questions to a winter storm expert and have them answered. This section also gives a brief biography of the expert.

1996-01-01

174

Phospholipase A2 activity during cold acclimation of wheat  

Technology Transfer Automated Retrieval System (TEKTRAN)

Phospholipase A2 (EC 3.1.1.4; PLA2) activity in wheat (Triticum aestivum L.) crown tissue from plants undergoing cold acclimation and/or chilling stress was investigated in a moderately cold tolerant winter wheat, a spring wheat, and a poorly cold tolerant winter wheat. Activity levels were inv...

175

Essential Outdoor Sun Safety Tips for Winter  

MedlinePLUS

... the risk for damage. Both snow and strong wind can wear away sunscreen and reduce its effectiveness, ... protect your skin from the bitter cold, heavy winds and winter sun, follow these important sun protection ...

176

Are summit metabolism and thermogenic endurance correlated in winter-acclimatized passerine birds?  

Microsoft Academic Search

Small birds exhibiting marked winter improvement of cold tolerance also show elevated summit metabolic rates (maximum cold-induced metabolic rate) in winter relative to summer. However, relatively large increases in cold tolerance can occur with only minor increments of maximum cold-induced metabolic rate and geographic variation in cold tolerance is not always positively correlated with variation in maximum cold-induced metabolic rate.

David L. Swanson

2001-01-01

177

Winter Weather  

MedlinePLUS

... weather presents hazards including slippery roads/surfaces, strong winds and environmental cold. Employers must prevent illnesses, injuries, ... from surfaces) Use extreme caution when working near power lines Prevent harmful exposure to cold temperatures and ...

178

Ponds Freeze in Winter -- Why Doesn't the Ocean?  

NSDL National Science Digital Library

In this activity, learners explore how salt water freezes in comparison to fresh water. Use this experiment to consider how pond animals survive cold winters in comparison to animals that live in the ocean. This resource includes information about freezing points as well as examples of how different animals respond to the winter cold.

New England Aquarium

2011-01-01

179

Winter Thunderstorms  

Microsoft Academic Search

THOSE of your readers who may observe thunderstorms in the British Isles during the winter months would give great assistance to an investigation of thunderstorms on which I am engaged if they would report by postcard when they observe lightning or thunder during this winter. When sheet lightning is observed at night the time and direction should be given, and

Charles J. P. Cave

1915-01-01

180

Winter Weeds.  

ERIC Educational Resources Information Center

Try to learn all you can about a plant in the winter. As the season changes, you can see what the dried seed pod is like in bloom. You are a convert if you notice a spectacular show of summer wildflowers and wonder what sort of winter weed will result. (Author/CM)

Lindberg, Lois

1981-01-01

181

Winter Wonderlands  

ERIC Educational Resources Information Center

Listening to people complain about the hardships of winter and the dreariness of the nearly constant gray sky prompted the author to help her sixth graders recognize and appreciate the beauty that surrounds them for nearly five months of the year in western New York. The author opines that if students could see things more artistically, the winter…

Coy, Mary

2011-01-01

182

Effects of a Short-Term Shift to Low Temperature and of Long-Term Cold Hardening on Photosynthesis and Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase and Sucrose Phosphate Synthase Activity in Leaves of Winter Rye (Secale cereale L.).  

PubMed Central

The effect of a short-term (hours) shift to low temperature (5[deg]C) and long-term (months) cold hardening on photosynthesis and carbon metabolism was studied in winter rye (Secale cereale L. cv Musketeer). Cold-hardened plants grown at 5[deg]C exhibited 25% higher in situ CO2 exchange rates than nonhardened plants grown at 24[deg]C. Cold-hardened plants maintained these high rates throughout the day, in contrast to nonhardened plants, which showed a gradual decline in photosynthesis after 3 h. Associated with the increase in photosynthetic capacity following cold hardening was an increase in ribulose-1,5-bisphosphate carboxylase/oxygenase and sucrose phosphate synthase activity and 3- to 4-fold increases in the pools of associated metabolites. Leaves of nonhardened plants shifted overnight to 5[deg]C required 9 h in the light at 5[deg]C before maximum rates of photosynthesis were reached. The gradual increase in photosynthesis in leaves shifted to 5[deg]C was correlated with a sharp decline in the 3-phosphoglycerate/triose phosphate ratio and by an increase in the ribulose bisphosphate/3-phosphoglycerate ratio, indicating the gradual easing of aninorganic phosphate-mediated feedback inhibition on photo-synthesis. We suggest that the strong recovery of photosynthesis in winter rye following cold hardening indicates that the buildup of photosynthetic enzymes, as well as those involved in sucrose synthesis, is an adaptive response that enables these plants to maximize the production of sugars that have both cryoprotective and storage functions that are critical to the performance of these cultivars during over-wintering. PMID:12232378

Hurry, V. M.; Malmberg, G.; Gardestrom, P.; Oquist, G.

1994-01-01

183

Vernalization: Winter and the Timing of Flowering in Plants  

E-print Network

Vernalization: Winter and the Timing of Flowering in Plants Dong-Hwan Kim,1 Mark R. Doyle,2 Sibum is vernalization, the process by which flowering is promoted as plants sense exposure to the cold temperatures of winter. A requirement for vernalization is an adaptive trait that helps prevent flowering before winter

Amasino, Richard M.

184

On a front line.  

PubMed

Like the patients, doctors in Sarajevo depend largely on humanitarian aid; everyone in the public sector has worked without pay for almost three years. The hospital is on a front line; yet the psychiatric department continues to function, even conducting large scale studies of psychosocial aspects of war in Bosnia-Hercegovina. The type of inpatient morbidity and treatment patterns have changed. A plethora of psychosocial rehabilitation programmes has emerged, including counselling, drop in centres, and attending to special needs of elderly people, schoolchildren, and women. The most prominent psychological symptoms were exhaustion at the prospect of a third winter of war and bewilderment at the Western stereotype of Bosnians as Muslim fundamentalists. PMID:7728062

Jones, L

1995-04-22

185

Gene expression analysis to understand cold tolerance in citrus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Citrus cultivars show a wide range of tolerance to cold temperatures. Lemons and limes are known to be sensitive to cold while certain mandarins and trifoliate oranges can endure severe winters. To understand the mechanism of cold tolerance in citrus, we selected three known cold-sensitive and three...

186

Surviving Winter  

NSDL National Science Digital Library

In this lesson designed to enhance literacy skills, students learn about the varied physical and behavioral adaptations that animals rely on to help them survive changing environmental conditions, such as the arrival of winter.

2010-11-17

187

Nuclear Winter.  

ERIC Educational Resources Information Center

"Nuclear Winter" was recently coined to describe the climatic and biological effects of a nuclear war. These effects are discussed based on models, simulations, scenarios, and projections. Effects on human populations are also considered. (JN)

Ehrlich, Anne

1984-01-01

188

Winter Weather  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Weather affects our everyday lives. Some days it's sunny and some days its not. The years weather is split up into seasons. 1. What are the four seasons? 2. What kind of weather do you see in the summer? 3. What kind of weather is unique to winter? 4. ...

Mrs. Bellows

2009-09-28

189

London 2013 Front propagation in spatially  

E-print Network

London 2013 Front propagation in spatially ergodic media Hiroshi Matano (University of Tokyo) UK-Japan Winter School "Nonlinear Analysis" Royal Academy of Engineering, London, Jan 7-11, 2013 #12;London 2013.-I. Nakamura and partly with J. Nolen #12;London 2013 1.Introduction Formulation of the problem #12;London 2013

Berndt, Jürgen

190

Common Cold  

MedlinePLUS

... nose, coughing - everyone knows the symptoms of the common cold. It is probably the most common illness. In ... avoid colds. There is no cure for the common cold. For relief, try Getting plenty of rest Drinking ...

191

Common cold  

MedlinePLUS

... are the most common reason that children miss school and parents miss work. Parents often get colds ... other children. A cold can spread quickly through schools or daycares. Colds can occur at any time ...

192

Climate warming will not decrease winter mortality  

NASA Astrophysics Data System (ADS)

It is widely assumed by policymakers and health professionals that the harmful health impacts of anthropogenic climate change will be partially offset by a decline in excess winter deaths (EWDs) in temperate countries, as winters warm. Recent UK government reports state that winter warming will decrease EWDs. Over the past few decades, however, the UK and other temperate countries have simultaneously experienced better housing, improved health care, higher incomes and greater awareness of the risks of cold. The link between winter temperatures and EWDs may therefore no longer be as strong as before. Here we report on the key drivers that underlie year-to-year variations in EWDs. We found that the association of year-to-year variation in EWDs with the number of cold days in winter ( <5 °C), evident until the mid 1970s, has disappeared, leaving only the incidence of influenza-like illnesses to explain any of the year-to-year variation in EWDs in the past decade. Although EWDs evidently do exist, winter cold severity no longer predicts the numbers affected. We conclude that no evidence exists that EWDs in England and Wales will fall if winters warm with climate change. These findings have important implications for climate change health adaptation policies.

Staddon, Philip L.; Montgomery, Hugh E.; Depledge, Michael H.

2014-03-01

193

Cold adaptations.  

PubMed

Nowdays, occupational and recreational activities in cold environments are common. Exposure to cold induces thermoregulatory responses like changes of behaviour and physiological adjustments to maintain thermal balance either by increasing metabolic heat production by shivering and/or by decreasing heat losses consecutive to peripheral cutaneous vasoconstriction. Those physiological responses present a great variability among individuals and depend mainly on biometrical characteristics, age, and general cold adaptation. During severe cold exposure, medical disorders may occur such as accidental hypothermia and/or freezing or non-freezing cold injuries. General cold adaptations have been qualitatively classified by Hammel and quantitatively by Savourey. This last classification takes into account the quantitative changes of the main cold reactions: higher or lower metabolic heat production, higher or lesser heat losses and finally the level of the core temperature observed at the end of a standardized exposure to cold. General cold adaptations observed previously in natives could also be developed in laboratory conditions by continuous or intermittent cold exposures. Beside general cold adaptation, local cold adaptation exists and is characterized by a lesser decrease of skin temperature, a more pronounced cold induced vasodilation, less pain and a higher manual dexterity. Adaptations to cold may reduce the occurrence of accidents and improve human performance as surviving in the cold. The present review describes both general and local cold adaptations in humans and how they are of interest for cold workers. PMID:19531907

Launay, Jean-Claude; Savourey, Gustave

2009-07-01

194

Reexamining the Cold Conveyor Belt  

Microsoft Academic Search

Despite the popularity of the conveyor-belt model for portraying the airflow through midlatitude cyclones, questions arise as to the path of the cold conveyor belt, the lower-tropospheric airflow poleward of and underneath the warm front. Some studies, beginning with Carlson's analysis of the eastern U.S. cyclone of 5 December 1977, depict the cold conveyor belt moving westward, reaching the northwest

David M. Schultz

2001-01-01

195

MAPPING FOR COLD TOLERANCE IN TWO RECOMBINANT INBRED LINE POPULATIONS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Wheat is the third major grain crop in the U.S after corn and soybeans. Winter wheat contributes about 70% of the total wheat produced in the country. Winter wheat production is affected by cold and freezing injury depending on the type of winters the farmers face. We are using SSR markers to map...

196

Cold sea survival.  

NASA Technical Reports Server (NTRS)

Two prototype three-man life rafts were evaluated during the winter months in Arctic waters off Kodiak Island, Alaska, to assess potential survival problems and determine tolerance limits. Each raft incorporated thermal characteristics specifically designed for cold water. Water and air temperatures varied from 0 to +2 C and -5 to +4 C respectively. All subjects were removed upon reaching subjective tolerance. The results showed that none of the clothing assemblies was adequate to maintain a person in comfort even with dry boarding. No significant biochemical shifts in the blood or urine were found. The TUL raft was found to be superior in its thermal characteristics and afforded better subject protection. General tolerance for cold water immersion, wet and dry, and cold water raft exposures are depicted graphically, based on previously reported data.

Veghte, J. H.

1972-01-01

197

Leap Day 2012 Severe Storm Front - Duration: 26 seconds.  

NASA Video Gallery

This movie was created using GOES-13 visible and infrared satellite imagery from Feb. 28 at 1245 UTC (7:45 a.m. EST) through March 1, and shows the progression of the cold front and associated low ...

198

Winter Hydrographer  

USGS Multimedia Gallery

Robert Bradley, a hydrologic technician with the Massachusetts USGS Office, headed to Maine to experience a winter ice measurement trip with Laura Flight, a hydrologic technician from the Maine USGS Office. Robert, originally from Florida, went to Aroostook County with Laura and got smacked in the f...

199

Winter Workshop.  

ERIC Educational Resources Information Center

Materials on 11 topics presented at a winter workshop for Quebec outdoor educators have been compiled into this booklet. Action story, instant replay, shoe factory, sound and action, and find an object to fit the description are described and recommended as group dynamic activities. Directions for five games (Superlative Selection; Data…

Council of Outdoor Educators of Quebec, Montreal.

200

Winter Depression  

NSDL National Science Digital Library

A U.K. psychologist has developed a complex mathematical formula using seven variables to predict winter's emotional low point. The good news is the worst day of the year was last week; nonetheless, seasonal depression remains a problem for many. The first link (1) is to an article about the equation worked out by Dr. Cliff Arnall, who specializes in seasonal disorders at the University of Cardiff, Wales. The second link is to a WebMD page (2) about winter depression, often referred to as Seasonal Affective Disorder (SAD). The next link (3) is to a recent news story about the results of a five-year study that found, rather than antidepressant drug therapy or air ionizers, light box therapy is the best remedy for the seasonal condition. The fourth link is to a set of Frequently Asked Questions (4) about SAD offered by Columbia Presbyterian Medical Center in New York City. The fifth link, to the Winter Depression Research Group at the University of Tromso in Norway(5), explains why Norway is a natural SAD research laboratory. The next link is to a international portal site (6) maintained by medical professionals and researchers in the field of light therapy and biological rhythms. The final webpage(7), from Psychology Today, compares the symptoms of winter depression with summer depression.

201

Winter Games.  

ERIC Educational Resources Information Center

Educators may find activities for indoor and outdoor winter programs in the games of the traditional Eskimo. These games are dominated by few-step operations and low level structural organization. For the most part they are quickly organized, begun, terminated, and ready to be recommenced. All types of games can be found, including quiet ones,…

Tarbuth, Lawson, Comp.

202

Cold Urticaria  

Microsoft Academic Search

\\u000a Cold urticaria is a physical urticaria in which patients experience ­urticaria, angioedema, or both in response to direct\\u000a contact with cold environments, the ingestion of cold beverages or foods, and the handling of cold objects. In this chapter,\\u000a we present two challenging cases of cold urticaria that highlight the diagnostic evaluation and treatment options for these\\u000a patients.

Grace Peace Yu; Alan A. Wanderer; Massoud Mahmoudi

203

Titan's Winter Polar Vortex  

NASA Technical Reports Server (NTRS)

Titan's atmosphere has provided an interesting study in contrasts and similarities with Earth's. While both have N$_2$ as the dominant constituent and comparable surface pressures $\\sim1$ bar, Titan's next most abundant molecule is CH$_4$, not O$_2$, and the dissociative breakup of CH$_4$ and N$_2$ by sunlight and electron impact leads to a suite of hydrocarbons and nitriles, and ultimately the photochemical smog that enshrouds the moon. In addition, with a 15.95-day period, Titan is a slow rotator compared to Earth. While the mean zonal terrestrial winds are geostrophic, Titan's are mostly cyclostrophic, whipping around the moon in as little as 1 day. Despite the different dynamical regime, Titan's winter stratosphere exhibits several characteristics that should be familiar to terrestrial meteorologists. The cold winter pole near the 1 -mbar level is circumscribed by strong winds (up to 190 m/s) that act as a barrier to mixing with airmasses at lower latitudes. There is evidence of enhancement of several organic species over the winter pole, indicating subsidence. The adiabatic heating associated with this subsidence gives rise to a warm anomaly at the 0.01-mbar level, raising the stratopause two scale heights above its location at equatorial latitudes. Condensate ices have been detected in Titan's lower stratosphere within the winter polar vortex from infrared spectra. Although not always unambiguously identified, their spatial distribution exhibits a sharp gradient, decreasing precipitously across the vortex away from the winter pole. The interesting question of whether there is important heterogeneous chemistry occurring within the polar vortex, analogous to that occurring in the terrestrial polar stratospheric clouds in the ozone holes, has not been addressed. The breakup of Titan's winter polar vortex has not yet been observed. On Earth, the polar vortex is nonlinearly disrupted by interaction with large-amplitude planetary waves. Large-scale waves have not been identified in Titan's atmosphere, so the decay of its polar vortex may be more gradual than on Earth. Observations from an extended Cassini mission into late northern spring should provide critical data indicating whether the vortex goes away with a bang or just fades away.

Flasar, F.M.; Achterberg, R.K.; Schinder, P.J.

2008-01-01

204

Modeling Experiment for winter circulation in Calcasieu Lake, LA  

NASA Astrophysics Data System (ADS)

Cold-front-induced water level oscillation and associated salinity distributions in Calcasieu Lake, southwestern Louisiana, were examined using a numerical model and field observations. The cold-front-induced flushing under the influence of Calcasieu River runoff, local wind stress, and tide determine the hydrodynamic features of Calcasieu Lake in winter. Based on observations carried out from Dec. 20, 2011 to Feb. 1, 2012, numerical model experiments with different conditions were conducted. The model predicts a depth-averaged flow pattern over the domain consisting of the shallow Calcasieu Lake and deep Ship Channel. A clockwise circulation in Calcasieu Lake coupled with the Ship Channel and a counterclockwise circulation in West Cove were demonstrated. It is through the shallow shoals, not the deep Ship Channel, that water from Calcasieu Lake flows into the ocean. This circulation pattern is typical of estuaries with shallow water influenced by river discharge and with weak tidally-induced motion. Both the observations and the model indicate saltwater intrusion along the Ship Channel into the northern lake. Salinity gradient induced baroclinic pressure gradient and Coriolis force also play relatively important roles in the circulation of Calcasieu Lake. Local wind stress played a negative role in the saltwater intrusion along the Ship Channel except under an east wind. The depth of the Ship Channel is a key factor influencing saltwater intrusion, the deeper the Channel, the more saltwater intrusion. Saltwater intrusion along the Ship Channel increases the magnitude of the Lake circulation and moderates salinity changes in adjacent wetlands caused by heavy rainfall. Circulation indicated by sum of water mass flux at transects Modeling experiment schedule

Lin, J.; Li, C.; Boswell, K.; Kimball, M.; Rozas, L.; Broussard, L.; Zhang, F.

2013-12-01

205

The Common Cold  

NSDL National Science Digital Library

When winter rolls around and we begin to spend more time indoors, the common cold becomes an unfortunate reality for many of us. But for something as common as the cold, misconceptions about it are remarkably common as well. The following collection of Web sites provides an in-depth look at the cold and the cold virus.The first site (1) comes from the Common Cold Care Center of Cardiff University in Wales, and offers a thorough and highly readable introduction to the common cold, including sections on conventional and alternative cold medications. Readers can brush up on their basic virology with the next Web site from HowStuffWorks to get a clear, general idea of how the cold virus infects the body (2). This site also explains why antibiotics have no effect on a virus, and includes numerous hypertext links to related HowStuffWorks Web pages. KidsHealth for Parents, a service of the Nemours Foundation, provides a straightforward guide to the symptoms of cold vs. flu, while also offering information on flu treatment options (3). The next Web site, from University of Guelph, contains an easy-to-understand comparison of bacteria and viruses (4). Readers can learn more about rhinoviruses, the family of viruses which account for about one-third of all colds, in the following Web site from the University of South Carolina's Microbiology and Immunology Online (5). The next Web site offers visitors a close-up look at human rhinovirus 14 with over a dozen 3-D images and movies from the University of Wisconsin-Madison Bock Laboratory (6). The following site describes the findings, as detailed in the Proceedings of the National Academy of Sciences, of a Purdue University research team that has analyzed on an atomic scale the structure of the cellular receptor that binds cold-causing viruses (7). And finally, find out about common cold clinical trials with ClinicalTrial.gov, a service of the National Institutes of Health (8).

Sohmer, Rachel.

2003-01-01

206

Winter thunderstorms in central Europe in the past and the present  

NASA Astrophysics Data System (ADS)

Thunderstorms in the territories of the Czech Republic and neighbouring countries are almost exclusively the only phenomena occurring in the warm season. In the cold half of the year, from October to March, an average incidence of thunderstorms is only 2%, with the least occurrence being recorded in January. Yet, winter thunderstorms are dangerous particularly for air traffic because during them, the cloud base is rapidly falling down and visibility is suddenly worsening due to heavy snowfall. Notwithstanding these facts, the issue of their occurrence in the central European space has been paid little attention so far. Long years of study into historical weather extremes in the territory of the Czech Republic revealed over 10 chronicle entries on the occurrence of winter thunderstorms in the period between November and February from the 16th to the beginning of the 20th centuries. The irregular phenomenon was even devoted three occasional prints in central Europe in the second half of the 16th century, two of which were issued in Germany. Fires caused by winter thunderstorms were no sporadic cases. The occurrence of thunderstorms in winter was apparently associated with the passage of pronounced cold fronts. This can be documented on cases from the end of December 1555 when heavy thunderstorms and consequent fires were recorded within a short period of time in Holland, Germany and in Czech lands. It is assumed that the situation in 1627 was similar when a winter thunderstorm was recorded in Prague and in Holešov, southeastern Moravia on 28 December. In February 1581, a thunderstorm in Prague became one of three unusual events publicized by the local occasional newspaper. The beginning of modern studies into winter thunderstorms dates back to the 1960s with the use of lightning flash counters and later also with the use of systems for large-scale lightning flash detection and localization. However, more comprehensive meteorological and climatological assessments of their occurrence are still missing. The authors of the paper aim at outlining possibilities of the incidence of winter thunderstorms in the present and at contributing with some answers to the question of the long-term fluctuation of their frequency.

Munzar, Jan; Franc, Marek

207

Winter Storms  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Form groups of three. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What usually happens when there is a large difference between the temperatures? 4. What happens when there ...

Mr. Sappa

2010-05-26

208

Winter Storm  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Form groups of three. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What usually happens when there is a large difference between the temperatures? ...

Miss Smith

2010-09-27

209

Winter Storm  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Form groups of three. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What usually happens when there is a large difference between the ...

Ashley Schilling

2010-05-26

210

Winter Storm  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Form groups of three. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. Does increased humidity usually increase of decrease your chances for rain? 4. What happens when there is ...

Sarah

2009-09-28

211

Winter Storm  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Form groups of three. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper. 1. In general, when are winds formed? 2. How can you get them to stop, when they are blowing? 3. What tends happens when there is a large difference between the temperatures? 4. What happens when there ...

Miss Liz

2010-05-26

212

Winter Blast.  

ERIC Educational Resources Information Center

Describes an art lesson for fifth- and sixth-grade students where they learn about the cold colors on the color wheel and apply that knowledge as they create a picture of a snowstorm. Explains that the students depict a snowstorm by layering the colors and drawings of snowflakes to make a three-dimensional effect. (CMK)

MacDonald, Beverley

1999-01-01

213

Common Cold  

NSDL National Science Digital Library

This Web site provides comprehensive information, selected by medical doctors, about the common cold. "The goal is to provide a framework for critical thinking which will allow informed decisions about medical care for the common cold." The section entitled Understanding Colds gives a detailed overview of how the cold virus invades the human body and how cold symptoms are caused. Information about preventing colds, and some of the complications that can occur are also included. The Special Features section includes one of the most interesting parts of the site -- Myths of the Common Cold. This site should be interesting to almost anyone, but perhaps more so for those of us who have recently had a cold.

214

Cold Stress  

MedlinePLUS

... on frostbite and hypothermia. eLCOSH Electronic Library of Construction Occupational Safety & Health (eLCOSH) Cold stress or hypothermia can affect construction workers who are not protected against cold. The ...

215

Vernalization of Green Plants of a Winter Wheat  

Microsoft Academic Search

SPRING cereals differ from winter cereals in their ability to initiate ears immediately under a favourable day-length, without cold treatment of the seed. Unvernalized winter cereals will eventually initiate ears, but even under the most favourable conditions this has not been found to occur until 6-8 weeks after planting1. `Vernalization' or cold treatment of the just-sprouted seed before planting will

M. B. Gott

1957-01-01

216

Winter snow  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. 1. What do you already know about the weather? 2. How does the weather effect you daily? Form groups of three. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What ...

Lori Peterson

2009-09-28

217

Molecular genetic studies of the memory of winter  

Microsoft Academic Search

Many plant species have evolved the ability to flower in the proper season by sensing environmental cues. The prolonged cold of winter is one such cue that certain plants use to acquire competence to flower the following spring. For example, biennials and winter annuals become established in one growing season and often flower quickly in the early spring of the

Sibum Sung; Richard M. Amasino

2006-01-01

218

Ammonia Loss from Urea Surface-Applied to Cold Soils Rick Engel and Clain Jones  

E-print Network

Ammonia Loss from Urea Surface-Applied to Cold Soils Rick Engel and Clain Jones Montana State spring is a common management practice for dryland winter wheat production in Montana. Soil temperatures during this time are often cold (

Lawrence, Rick L.

219

Winter bat activity in the Canadian prairies  

Microsoft Academic Search

Periodic arousal from hibernation among mammalian hibernators is poorly understood. In bats, arousal is often associated with flight. We acoustically monitored two rocky areas along the Red Deer River in southeastern Alberta for bat activity in autumn, winter, and spring months. We found bats to be active in all months and at unexpectedly cold tem- peratures (coldest activity -8 8C).

C. L. Lausen; R. M. R. Barclay

2006-01-01

220

The Stratospheric Polar Vortex in Winter  

Microsoft Academic Search

In winter the polar stratospheric air within the earth's shadow forms the core of an intense 'cold low' which extends from about 10 km to at least 50 km and possibly to the base of the ionosphere. Compared with the tropospheric general circulation, this vortex seems to be remarkably stable, particularly in the Southern Hemisphere. Recent research work in Canada

Clarence E. Palmer

1959-01-01

221

Cold Fusion.  

ERIC Educational Resources Information Center

Discusses ways of preparing school-building roofs for the winter season by paying attention to common problem areas. Also highlights the use of white elastomeric roof coatings, their benefits, and considerations when applying them. (GR)

Dutton, Eileen; Salazar, Chris

1998-01-01

222

Interannual salinity variability of the Northern Yellow Sea Cold Water Mass  

NASA Astrophysics Data System (ADS)

This paper discusses the interannual variability of the Northern Yellow Sea Cold Water Mass (NYSCWM) and the factors that influence it, based on survey data from the 1976-2006 national standard section and the Korea Oceanographic Data Center, monthly E-P flux data from the European Centre for Medium-Range Weather Forecasts, and meridional wind speed data from the International Comprehensive Ocean-Atmosphere Data Set. The results show that: 1) the mean salinity of the NYSCWM center has a slightly decreasing trend, which is not consistent with the high salinity center; 2) both the southern salinity front and the halocline of the NYSCWM display a weakening trend, which indicates that the difference between the NYSCWM and coastal water decreases; 3) the Yellow Sea Warm Current intrusion, the E-P flux of the northern Yellow Sea, and the strength of the winter monsoon will affect the NYSCWM salinity during the following summer.

Li, Ang; Yu, Fei; Diao, Xinyuan

2015-01-01

223

Physiological processes during winter dormancy and their ecological significance  

SciTech Connect

Lengthy and severe winters require that trees in the forests of boreal and mountain zones undergo winter dormancy. Physiologically, a high resistance to subfreezing temperatures and concomitant dehydration are necessary. To accomplish this dormancy, both physiological and structural changes are needed at the cellular level that require induction by endogenous and photoperiodic control early in autumn. Endogenous rhythmicity promotes cold hardening in early autumn and the persistence of hardiness throughout the winter. Numerous physiological functions are maintained at a reduced level, or become completely inhibited during true winter dormancy. Winter hardiness also includes the capability to minimize water loss effectively when water uptake is severely impeded or impossible. Anatomical features such as tracheids act to minimize xylem embolism during frequent freeze-thaw cycles, and {open_quotes}crown{close_quotes} tissues enable buds to stay in a dehydrated and, thus, more resistant state during winter. Both these structural features are adaptations that contribute to the dominance of conifers in cold climates. Interestingly, deciduous tree species rather than evergreen conifers dominate in the most severe winter climates, although it is not clear whether limitations during winter, during the summer growth period, or during both are most limiting to conifer tree ecology. Additional work that evaluates the importance of winter and summer growth restriction, and their interaction, is needed before a comprehensive understanding of conifer tree ecophysiology will be possible.

Havranek, W.M.; Tranquillini, W.

1995-07-01

224

Radar Backscatter Across the Gulf Stream Sea Surface Temperature Front  

NASA Technical Reports Server (NTRS)

Ocean backscatter signatures were measured by the Jet Propulsion Laboratory airborne NUSCAT K(sub u)-band scatterometer across the Gulf Stream sea surface temperature front. The measurements were made during the Surface Wave Dynamics Experiment (SWADE) off the coast of Virginia and Maryland in the winter of 1991.

Nghiem, S. V.; Li, F. K.; Walsh, E. J.; Lou, S. H.

1998-01-01

225

Cold Intolerance  

MedlinePLUS

... of the brain that causes blood vessels to contract, and the hypothalmus, the part that controls the ... message to the capillaries of the skin to contract when it is cold (Bodian, 1949) . Consequently, as ...

226

When hot water freezes before cold  

E-print Network

I suggest that the origin of the Mpemba effect (the freezing of hot water before cold) is freezing-point depression by solutes, either gaseous or solid, whose solubility decreases with increasing temperature so that they are removed when water is heated. They are concentrated ahead of the freezing front by zone refining in water that has not been heated, reduce the temperature of the freezing front, and thereby reduce the temperature gradient and heat flux, slowing the progress of the front. I present a simple calculation of this effect, and suggest experiments to test this hypothesis.

J. I. Katz

2006-04-27

227

When hot water freezes before cold  

E-print Network

I suggest that the origin of the Mpemba effect (the freezing of hot water before cold) is freezing-point depression by solutes, either gaseous or solid, whose solubility decreases with increasing temperature so that they are removed when water is heated. They are concentrated ahead of the freezing front by zone refining in water that has not been heated, reduce the temperature of the freezing front, and thereby reduce the temperature gradient and heat flux, slowing the progress of the front. I present a simple calculation of this effect, and suggest experiments to test this hypothesis.

Katz, J I

2006-01-01

228

When hot water freezes before cold  

NASA Astrophysics Data System (ADS)

I suggest that the origin of the Mpemba effect (the freezing of hot water before cold) is due to freezing-point depression by solutes, either gaseous or solid, whose solubility decreases with increasing temperature so that they are removed when water is heated. The solutes are concentrated ahead of the freezing front by zone refining in water that has not been heated, reducing the temperature of the freezing front, and thereby reducing the temperature gradient and heat flux, slowing the progress of the freezing front. I present a simple calculation of this effect, and suggest experiments to test this hypothesis.

Katz, J. I.

2009-01-01

229

The influence of riming and frontal dynamics on winter precipitation chemistry in level terrain  

NASA Astrophysics Data System (ADS)

The relative influences of accretional ice crystal growth (riming) and frontal passages on winter precipitation chemistry were evaluated in level terrain in east central Illinois during the winter of 1992. Six precipitation events were analyzed during the period January to March, 1992. Five events were characterized by the passage of cold Arctic fronts and no riming was observed. Precipitation chemistry was observed to change substantially during frontal passage, reflecting the different pollutant loadings in pre- and post-frontal air masses. Precipitation that fell on March 11, 1992, associated with a warm or occluded frontal system, was moderately rimed. Application of a linear multiple regression model revealed that most of the temporal variations in precipitation chemistry during this event could be explained by changes in the degree of riming and changes in the identity of the air mass producing precipitation above the site. Accreted ice crystal mass was dominated by cloud drops with diameters between 20 and 40 ?m, indicating that the composition of drops in this size range exert the most influence on precipitation chemistry.

Devulapalli, Srinivas S. N.; Collett, Jeffrey L.

230

Porous Pavements in Cold Climates Part 1: Design, Installation, and  

E-print Network

Porous Pavements in Cold Climates Part 1: Design, Installation, and Maintenance A Green-Graded Friction Courses (2002) 3 #12;Part I Overview 1. State of the Practice 2. Common Design and Installation Cold climate performance is strong Winter maintenance has tremendous potential salt reduction Design

231

A computer model for predicting grapevine cold hardiness  

Technology Transfer Automated Retrieval System (TEKTRAN)

We developed a robust computer model of grapevine bud cold hardiness that will aid in the anticipation of and response to potential injury from fluctuations in winter temperature and from extreme cold events. The model uses time steps of 1 day along with the measured daily mean air temperature to ca...

232

Nitrification treatment of swine wastewater under cold temperatures  

Technology Transfer Automated Retrieval System (TEKTRAN)

In addition to N load, cold weather nitrification is an important consideration for stabilized performance of biological processes applied to continuous animal production systems. We conducted a winter simulation experiment in the laboratory to evaluate performance of immobilized bacteria under cold...

233

April 2007 Cold Wave National Oceanic and Atmospheric Administration  

E-print Network

of the event in concert with crop emergence and tree blooms. Winter wheat across the central Plains and Midwest crops. Several factors made this cold wave more harmful to agricultural interests than similar events, a pattern shift brought this cold Arctic air southward into the central and eastern U.S. This record

234

Cold injuries.  

PubMed

Exposure to cold can produce a variety of injuries that occur as a result of man's inability to adapt to cold. These injuries can be divided into localized injury to a body part, systemic hypothermia, or a combination of both. Body temperature may fall as a result of heat loss by radiation, evaporation, conduction, and convection. Hypothermia or systemic cold injury occurs when the core body temperature has decreased to 35 degrees C (95 degrees F) or less. The causes of hypothermia are either primary or secondary. Primary, or accidental, hypothermia occurs in healthy individuals inadequately clothed and exposed to severe cooling. In secondary hypothermia, another illness predisposes the individual to accidental hypothermia. Hypothermia affects multiple organs with symptoms of hypothermia that vary according to the severity of cold injury. The diagnosis of hypothermia is easy if the patient is a mountaineer who is stranded in cold weather. However, it may be more difficult in an elderly patient who has been exposed to a cold environment. In either case, the rectal temperature should be checked with a low-reading thermometer. The general principals of prehospital management are to (1) prevent further heat loss, (2) rewarm the body core temperature in advance of the shell, and (3) avoid precipitating ventricular fibrillation. There are two general techniques of rewarming--passive and active. The mechanisms of peripheral cold injury can be divided into phenomena that affect cells and extracellular fluids (direct effects) and those that disrupt the function of the organized tissue and the integrity of the circulation (indirect effects). Generally, no serious damage is seen until tissue freezing occurs. The mildest form of peripheral cold injury is frostnip. Chilblains represent a more severe form of cold injury than frostnip and occur after exposure to nonfreezing temperatures and damp conditions. Immersion (trench) foot, a disease of the sympathetic nerves and blood vessels in the feet, is observed in shipwreck survivors or in soldiers whose feet have been wet, but not freezing, for long periods. Patients with frostbite frequently present with multisystem injuries (e.g., systemic hypothermia, blunt trauma, substance abuse). The freezing of the corneas has been reported to occur in individuals who keep their eyes open in high wind-chill situations without protective goggles (e.g., snowmobilers, cross-country skiers). PMID:15715518

Long, William B; Edlich, Richard F; Winters, Kathryne L; Britt, L D

2005-01-01

235

Fronts, fish, and predators  

NASA Astrophysics Data System (ADS)

Ocean fronts play a key role in marine ecosystems. Fronts shape oceanic landscapes and affect every trophic level across a wide range of spatio-temporal scales, from meters to thousands of kilometers, and from days to millions of years. At some fronts, there is an elevated rate of primary production, whereas at others, plankton is aggregated by advection and by the behavior of organisms moving against gradients in temperature, salinity, light irradiance, hydrostatic pressure and other physico-chemical and biological factors. Lower trophic level organisms - phytoplankton and zooplankton - that are aggregated in sufficient densities, attract organisms from higher trophic levels, from planktivorous schooling fish to squid, large piscivorous fish, seabirds and marine mammals. Many species have critical portions of their life stages or behaviors closely associated with fronts, including spawning, feeding, ontogenetic development, migrations, and other activities cued to frontal dynamics. At different life stages, an individual species or population might be linked to different fronts. The nature and strength of associations between fronts and biota depend on numerous factors such as the physical nature and spatio-temporal scales of the front and the species and their life stages in question. In other words, fronts support many different niches and micro/macro-habitats over a wide range of spatial and temporal scales.

Belkin, Igor M.; Hunt, George L.; Hazen, Elliott L.; Zamon, Jeannette E.; Schick, Robert S.; Prieto, Rui; Brodziak, Jon; Teo, Steven L. H.; Thorne, Lesley; Bailey, Helen; Itoh, Sachihiko; Munk, Peter; Musyl, Michael K.; Willis, Jay K.; Zhang, Wuchang

2014-09-01

236

Cold response of annual Mediterranean pasture legumes  

Microsoft Academic Search

SUMMARY - In southern Europe, the trend towards low input agriculture gives new incentives to sow forages, legumes in particular, with the aim of improving natural pastures, increase the quality of animal feeding and improve soil fertility. However, growth of forage crops in these areas is seriously limited by the ability of each species to grow during cold winters. Therefore,

M. Hekneby; M. Sánchez-Díaz

237

Nutrition Frontiers - Winter 2010  

Cancer.gov

Nutrition Frontiers - Winter 2010 Winter 2010 Volume 1, Issue 1 Dear Colleague, Welcome to the first issue of Nutrition Frontiers, a quarterly newsletter from the Nutritional Science Research Group (NSRG), Division of Cancer Prevention, NCI. In this

238

Cold Metal  

NSDL National Science Digital Library

In this activity, learners discover that our hands are not reliable thermometers. Learners place their palms flat on various surfaces (metal, wood, glass, etc.) and compare how cold the surfaces feel. Learners are challenged to arrange the materials in order from cold to warm. Then, they use a thermometer to measure the temperature of each surface, only to discover that the surfaces are all at the same temperature. Use this activity to talk about temperature-sensitive nerves in skin as well as how different materials act as insulators and conductors of heat.

2012-01-30

239

Modeling cold tolerance in the mountain pine beetle, Dendroctonus ponderosae  

Microsoft Academic Search

Cold-induced mortality is a key factor driving mountain pine beetle, Dendroctonus ponderosae, population dynamics. In this species, the supercooling point (SCP) is representative of mortality induced by acute cold exposure. Mountain pine beetle SCP and associated cold-induced mortality fluctuate throughout a generation, with the highest SCPs prior to and following winter. Using observed SCPs of field-collected D. ponderosae larvae throughout

Jacques Régnière; Barbara Bentz

2007-01-01

240

When hot water freezes before cold  

Microsoft Academic Search

I suggest that the origin of the Mpemba effect (the freezing of hot water before cold) is due to freezing-point depression by solutes, either gaseous or solid, whose solubility decreases with increasing temperature so that they are removed when water is heated. The solutes are concentrated ahead of the freezing front by zone refining in water that has not been

J. I. Katz

2009-01-01

241

When hot water freezes before cold  

Microsoft Academic Search

I suggest that the origin of the Mpemba effect (the freezing of hot water before cold) is freezing-point depression by solutes, either gaseous or solid, whose solubility decreases with increasing temperature so that they are removed when water is heated. They are concentrated ahead of the freezing front by zone refining in water that has not been heated, reduce the

J. I. Katz

2006-01-01

242

The long summer: pre-wintering temperatures affect metabolic expenditure and winter survival in a solitary bee.  

PubMed

The impact of climate change on insect populations depends on specific life cycle traits and physiological adaptations. The solitary bee Osmia lignaria winters as a pre-emergent adult, and requires a period of cold temperature for winter diapause completion. It is a univoltine species, and diapause induction does not depend on photoperiod. To understand the potential effects of longer summers on O. lignaria populations, we exposed individuals to three treatments simulating early, mid and late winter arrivals, and measured respiration rates, metabolic expenditure, weight loss, fat body depletion, lipid levels and winter mortality. The early-winter treatment disrupted diapause development, but had no apparent negative effects on fitness. In contrast, late-winter bees had a greater energetic expenditure (1.5-fold), weight (1.4-fold) and lipid (2-fold) loss, greater fat body depletion, and a 19% increase in mortality compared to mid-winter bees. We also monitored adult eclosion and arrival of winter temperatures under natural conditions in four years. We found a positive correlation between mean degree-day accumulation during pre-wintering (a measure of asynchrony between adult eclosion and winter arrival) and yearly winter mortality. Individually, bees experiencing greater degree-day accumulations exhibited reduced post-winter longevity. Timing of adult eclosion in O. lignaria is dependent on the duration of the prepupal period, which occurs in mid-summer, is also diapause-mediated, and is longer in populations from southerly latitudes. In a global warming scenario, we expect long summer diapause phenotypes to replace short summer diapause phenotypes, effectively maintaining short pre-wintering periods in spite of delayed winter arrivals. PMID:21910996

Sgolastra, Fabio; Kemp, William P; Buckner, James S; Pitts-Singer, Theresa L; Maini, Stefano; Bosch, Jordi

2011-12-01

243

Negative Ion Density Fronts  

SciTech Connect

Negative ions tend to stratify in electronegative plasmas with hot electrons (electron temperature Te much larger than ion temperature Ti, Te > Ti ). The boundary separating a plasma containing negative ions, and a plasma, without negative ions, is usually thin, so that the negative ion density falls rapidly to zero-forming a negative ion density front. We review theoretical, experimental and numerical results giving the spatio-temporal evolution of negative ion density fronts during plasma ignition, the steady state, and extinction (afterglow). During plasma ignition, negative ion fronts are the result of the break of smooth plasma density profiles during nonlinear convection. In a steady-state plasma, the fronts are boundary layers with steepening of ion density profiles due to nonlinear convection also. But during plasma extinction, the ion fronts are of a completely different nature. Negative ions diffuse freely in the plasma core (no convection), whereas the negative ion front propagates towards the chamber walls with a nearly constant velocity. The concept of fronts turns out to be very effective in analysis of plasma density profile evolution in strongly non-isothermal plasmas.

Igor Kaganovich

2000-12-18

244

Negative ion density fronts  

NASA Astrophysics Data System (ADS)

Negative ions tend to stratify in electronegative plasmas with hot electrons (electron temperature Te much larger than ion temperature Ti, Te?Ti). The boundary separating a plasma containing negative ions, and a plasma without negative ions, is usually thin so that the negative ion density falls rapidly to zero—forming a negative ion density front. Theoretical, experimental, and numerical results giving the spatio-temporal evolution of negative ion density fronts during plasma ignition, the steady state, and extinction (afterglow) are reviewed. During plasma ignition, negative ion fronts are the result of the break of smooth plasma density profiles during nonlinear convection. In a steady-state plasma, the fronts are boundary layers with steepening of ion density profiles due to nonlinear convection also. But during plasma extinction, the ion fronts are of a completely different nature. Negative ions diffuse freely in the plasma core (no convection), whereas the negative ion front propagates towards the chamber walls with a nearly constant velocity. The concept of fronts turns out to be very effective in the analysis of plasma density profile evolution in strongly nonisothermal plasmas.

Kaganovich, Igor

2001-05-01

245

[An entomological case report during the winter months: estimation of the post-mortem interval considering the influence of cold temperatures on the development of the forensically important blowfly Calliphora vomitoria].  

PubMed

The authors describe a case report with entomological estimation of the post-mortem interval in the winter months. In early December 2007, the body of a suicide was discovered not far from a lake near Bonn in North Rhine-Westphalia four weeks after the man had disappeared from a hospital. The corpse was very well preserved and did not show any signs of advanced putrefaction. The stage of decomposition did not allow a correct estimation of the time since death. Infestation of insect larvae of the species Calliphora vomitoria was detected in the oral cavity as well as in the self-inflicted deep cut to the throat responsible for death. The age of the larvae was determined by considering the specific minimum threshold of the species (minimum temperature necessary for development). To estimate the time until the blowflies detect the body and start to oviposit, the authors ran an experiment with a pig in a comparable environment with similar temperatures. Altogether, these investigations suggested that the man had committed suicide shortly after disappearing from the hospital. Without the entomological evaluation it would have been very difficult to narrow down the post-mortem interval correctly. PMID:19432091

Wetzel, Waltraud; Reibe, Saskia; Madea, Burkhard

2009-01-01

246

A late winter hydrographic section from Tasmania to Antarctica  

Microsoft Academic Search

A hydrographic section between Tasmania and Antarctica was occupied in late winter 1991 as part of the World Ocean Circulation Experiment (WOCE). The primary purpose of the WOCE repeat section SR3 is to measure the exchange between the Indian and Pacific Oceans south of Australia. This paper describes the fronts, water masses and transport observed on the first occupation of

Stephen R. Rintoul; John L. Bullister

1999-01-01

247

DEACCLIMATION AND REACCLIMATION OF COLD-HARDY PLANTS: CURRENT UNDERSTANDING AND EMERGING CONCEPTS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The ability of cold-hardy plants to resist deacclimation during transient warm spells and to reacclimate when cold temperatures return are significant for winter survival. Yet compared to the volume of research on the biology of cold acclimation, relatively little is known about how plants maintain...

248

Relativistic Runaway Ionization Fronts  

NASA Astrophysics Data System (ADS)

We investigate the first example of self-consistent impact ionization fronts propagating at relativistic speeds and involving interacting, high-energy electrons. These fronts, which we name relativistic runaway ionization fronts, show remarkable features such as a bulk speed within less than one percent of the speed of light and the stochastic selection of high-energy electrons for further acceleration, which leads to a power-law distribution of particle energies. A simplified model explains this selection in terms of the overrun of Coulomb-scattered electrons. Appearing as the electromagnetic interaction between electrons saturates the exponential growth of a relativistic runaway electron avalanche, relativistic runaway ionization fronts may occur in conjunction with terrestrial gamma-ray flashes and thus explain recent observations of long, power-law tails in the terrestrial gamma-ray flash energy spectrum.

Luque, A.

2014-01-01

249

Hot, Cold, and Really Cold.  

ERIC Educational Resources Information Center

Describes a physics experiment investigating temperature prediction and the relationship between the physical properties of heat units, melting, dissolving, states of matter, and energy loss. Details the experimental setup, which requires hot and cold water, a thermometer, and ice. Notes that the experiment employs a deliberate counter-intuitive…

Leyden, Michael

1997-01-01

250

Migrations of the North Atlantic Polar front during the last 300 ka: Evidence from planktic foraminiferal data  

NASA Astrophysics Data System (ADS)

The main migrations of the Polar front (PF) during the last 300 ka were identified using planktic foraminiferal census data and derived from them sea surface paleotemperature (SST) estimates in two synchronized AMK-4438 and M23414 cores recovered directly beneath the main stream of the North Atlantic Current (NAC) south of Iceland. During the summer seasons, the cold waters adjacent to the PF did not reach the studied sites. These waters occurred here only during the winter seasons of MIS 2, 6, and 8. The northern part of the study area was influenced by the arctic waters more often than its southern part. During MIS 8 and 6 isotherms in the North Atlantic had mainly the subzonal orientation, while during MIS 2-4 they had the submeridional orientation. During the interglacials, the PF was located northward and westward from the study area. During MIS 7, the front was presumably situated closer to the study area in comparison with its modern position, and the isotherms were oriented mainly subzonal. For the MIS 5e period, we observed the most distant retreat of PF from the investigated area in the western and northwestern direction in relation to the anomalous deflection of the NAC to the north-west (intensification of the Irminger current) and the predominance of the submeridional orientation of the isotherms in the study area. During MIS 1, as well as MIS 7, the isotherms in the study area had mainly the subzonal orientation.

Bashirova, L. D.; Kandiano, E. S.; Sivkov, V. V.; Bauch, H. A.

2014-11-01

251

De Bilt, 2012 | KNMI-publication 231 On future Western European winters  

E-print Network

-2040) . . . . . . . . . . . . . . . . . . . . . 27 3.7 Mechanism. What causes the reduction of the daily temperature variability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Linking cold winter weather and atmospheric blocking? . . . . . . . . . . . . . . 7 2.3 Heating degreedays. Climatology, extremes and the effect of the wind

Haak, Hein

252

Genotypic differences in cold tolerance are masked by high sucrose and cytokinin in shoot cultures of sugarbeet  

Microsoft Academic Search

Cold tolerance of field grown plants and shoot cultures of a commercial sugarbeet cultivar, ‘Hilma’, was compared with that of two cultivars bred for improved cold tolerance, ‘Monofeb’ and ‘Winter Hybrid 88619’. Leaves of ‘Monofeb’ and ‘Winter Hybrid 88619’ showed an increase in frost tolerance compared to Hilma, as assessed by electrolyte leakage measurements, in both July, and November. However,

Philip J. Dix; Iseult Finch; James I. Burke

1994-01-01

253

Impact of declining Arctic sea ice on winter snowfall  

PubMed Central

While the Arctic region has been warming strongly in recent decades, anomalously large snowfall in recent winters has affected large parts of North America, Europe, and east Asia. Here we demonstrate that the decrease in autumn Arctic sea ice area is linked to changes in the winter Northern Hemisphere atmospheric circulation that have some resemblance to the negative phase of the winter Arctic oscillation. However, the atmospheric circulation change linked to the reduction of sea ice shows much broader meridional meanders in midlatitudes and clearly different interannual variability than the classical Arctic oscillation. This circulation change results in more frequent episodes of blocking patterns that lead to increased cold surges over large parts of northern continents. Moreover, the increase in atmospheric water vapor content in the Arctic region during late autumn and winter driven locally by the reduction of sea ice provides enhanced moisture sources, supporting increased heavy snowfall in Europe during early winter and the northeastern and midwestern United States during winter. We conclude that the recent decline of Arctic sea ice has played a critical role in recent cold and snowy winters. PMID:22371563

Liu, Jiping; Curry, Judith A.; Wang, Huijun; Song, Mirong; Horton, Radley M.

2012-01-01

254

Improved antioxidative protection in winter swimmers.  

PubMed

Adaptation to oxidative stress is an improved ability to resist the damaging effects of reactive oxygen species, resulting from pre-exposure to a lower dose. Changes in uric acid and glutathione levels during ice-bathing suggest that the intensive voluntary short-term cold exposure of winter swimming produces oxidative stress. We investigated whether the repeated oxidative stress in winter swimmers results in improved antioxidative adaptation. We obtained venous blood samples from winter swimmers and determined important components of the antioxidative defense system in the erythrocytes or blood plasma: reduced and oxidized glutathione (GSH and GSSG), and the activities of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (Cat). The control group consisted of healthy people who had never participated in winter swimming. The baseline concentration of GSH and the activities of erythrocytic SOD and Cat, were higher in winter swimmers. We interpret this as an adaptative response to repeated oxidative stress, and postulate it as a new basic molecular mechanism of increased tolerance to environmental stress. PMID:10396606

Siems, W G; Brenke, R; Sommerburg, O; Grune, T

1999-04-01

255

Winters fuels report  

SciTech Connect

The outlook for distillate fuel oil this winter is for increased demand and a return to normal inventory patterns, assuming a resumption of normal, cooler weather than last winter. With industrial production expected to grow slightly from last winter`s pace, overall consumption is projected to increase 3 percent from last winter, to 3.4 million barrels per day during the heating season (October 1, 1995-March 31, 1996). Much of the supply win come from stock drawdowns and refinery production. Estimates for the winter are from the Energy Information Administration`s (EIA) 4th Quarter 1995 Short-Tenn Energy Outlook (STEO) Mid-World Oil Price Case forecast. Inventories in place on September 30, 1995, of 132 million barrels were 9 percent below the unusually high year-earlier level. Inventories of high-sulfur distillate fuel oil, the principal type used for heating, were 13 percent lower than a year earlier. Supply problems are not anticipated because refinery production and the ready availability of imports should be adequate to meet demand. Residential heating off prices are expected to be somewhat higher than last winter`s, as the effects of lower crude oil prices are offset by lower distillate inventories. Heating oil is forecast to average $0.92 per gallon, the highest price since the winter of 1992-93. Diesel fuel (including tax) is predicted to be slightly higher than last year at $1.13 per gallon. This article focuses on the winter assessment for distillate fuel oil, how well last year`s STEO winter outlook compared to actual events, and expectations for the coming winter. Additional analyses include regional low-sulfur and high-sulfur distillate supply, demand, and prices, and recent trends in distillate fuel oil inventories.

NONE

1995-10-27

256

Nuclear winter or nuclear fall?  

NASA Astrophysics Data System (ADS)

Climate is universal. If a major modern nuclear war (i.e., with a large number of small-yield weapons) were to happen, it is not even necessary to have a specific part of the world directly involved for there to be cause to worry about the consequences for its inhabitants and their future. Indeed, smoke from fires ignited by the nuclear explosions would be transported by winds all over the world, causing dark and cold. According to the first study, by Turco et al. [1983], air surface temperature over continental areas of the northern mid-latitudes (assumed to be the nuclear war theatre) would fall to winter levels even in summer (hence the term “nuclear winter”) and induce drastic climatic conditions for several months at least. The devastating effects of a nuclear war would thus last much longer than was assumed initially. Discussing to what extent these estimations of long-term impacts on climate are reliable is the purpose of this article.

Berger, André

257

Nonclassical Cold-Frontal Structure Caused by Dry Subcloud Air in Northern Utah during the Intermountain Precipitation Experiment (IPEX)  

Microsoft Academic Search

The purpose of the Intermountain Precipitation Experiment (IPEX) is to improve understanding of precipitating systems in the Intermountain West. Instrumentation deployed during the field phase of IPEX sampled a strong cold front and associated convection that moved through northern Utah on 14-15 February 2000. The surface cold front was characterized by a sharp temperature drop (88C in 8 min), strong

David M. Schultz; Robert J. Trapp

2003-01-01

258

Discovering Traits Controlling Winter-hardiness and Spring Regrowth in Diverse Switchgrass Germplasm  

Technology Transfer Automated Retrieval System (TEKTRAN)

Switchgrass (Panicum virgatum L.) is a perennial bioenergy plant that needs to survive both repeated harvests and harsh winters experienced in the Central and Northern USA. The plant traits that control winter-hardiness are not known, but will be critical to the future development of cold-tolerant,...

259

Initial Study of Solar Control Film in a Hotel Guest Room in Winter  

E-print Network

was carried out in summer to estimate its positive effect on energy saving. There is also a paucity of experiments conducted in winter to show its negative effect in cold weather. This study carries out an experiment in hotel guest rooms in winter in order...

Chan, W. C.; Chen, Y.; Mak, B.; Li, D.; Huang, Y.; Xie, H.; Hou, G.

2006-01-01

260

Development of the polar vortex in the 1999-2000 Arctic winter stratosphere  

NASA Technical Reports Server (NTRS)

The 1999-2000 Arctic stratospheric vortex was unusually cold, especially in the early winter lower stratosphere, with a larger area near polar stratospheric cloud formation temperatures in Dec and Jan, and much lower temperatures averaged over Nov-Jan, than any previously observed Arctic winter.

Manney, G. L.; Sabutis, J. L.

2000-01-01

261

Condensation during Titan's Polar Winter  

NASA Astrophysics Data System (ADS)

Titan is currently experiencing winter in its northern hemisphere and the lower atmosphere of its north polar region has been in prolonged darkness since the solstice in October 2002. As a result, the north polar region is currently characterised by cold stratospheric temperatures and there is enrichment of trace gases due to downward atmospheric motion (e.g. Teanby et al., Icarus 181 pp. 243-255, 2006). These conditions make the polar winter very suitable for cloud formation in the stratosphere. A simple transport and condensation model has been made to explore condensation processes in Titan's northern stratosphere. In the model, the atmosphere is advected downwards and clouds are formed as the saturation pressure of various gases is reached. Upper limits of the gases C4N2 and propionitrile (C2H5CN) were determined from Cassini Composite Infrared Spectrometer data to assess scenarios of chemical disequilibrium where the gas phase is far less abundant than the solid phase. The upper limit for C4N2 is 9e-9, which discounts the massive C4N2 build-up in the polar winter proposed by Samuelson et al. (PSS 45, pp. 941-948, 1997) to explain the observed C4N2 cloud at the Voyager epoch. The propionitrile upper limit is 8e-9, which is several orders of magnitude less than needed to create the condensate feature at 220 cm-1 of Khanna (Icarus 177, pp. 116-121) and de Kok et al. (Icarus, in press), assuming it is propionitrile ice, under the steady-state conditions explored by the aformentioned model. HCN ice seems to play an important role in the formation of a massive polar cloud (Haze B in de Kok et al., Icarus, in press), because of the unavailability of sufficient condensable gas other than HCN (and possibly HC3N) to produce the condensate features seen in far-infrared spectra at 220 cm-1.

de Kok, Remco; Irwin, P. G.; Teanby, N. A.; Fletcher, L. N.; Howett, C. J.; Calcutt, S. B.; Bowles, N. E.; Taylor, F. W.

2007-10-01

262

Subtropical Shelf Front off eastern South America  

NASA Astrophysics Data System (ADS)

Historical hydrographic data from the continental shelf off eastern South America are used to examine the thermohaline properties of the water masses in the region between 20°S and 40°S. The continental shelf water masses are originated by dilution of open ocean waters of the western boundary currents of the South Atlantic Ocean. On the basis of temperature-salinity relation, two distinct water masses are identified, namely, the Subantarctic Shelf Water and the Subtropical Shelf Water. Subantarctic Shelf Water originates by dilution of Subantarctic Water, primarily in the southeast Pacific, due to excess precipitation and continental runoff and enters the continental shelf near 55°S. The Subtropical Shelf Water is modified South Atlantic Central Water diluted by continental runoff from the coast of Brazil. In addition, substantial dilution of the upper shelf waters takes place at the mouth of Río de la Plata (approximately located at 36°S) and, in a lesser extent, at the Patos-Mirim Lagoon (at 32°S). The Río de la Plata and the Patos outflows form a low-salinity tongue that caps the shelf water leading to a salinity decrease to values <30. The low-salinity tongue extends northward over the shelf penetrating farther north in winter than in summer. The extent of the low-salinity water has a strong impact on the vertical stratification and acts to limit winter convection to the layer above the halocline. There is little or no indication of mixing between Subantarctic Shelf Water and Subtropical Shelf Water. An intense temperature, salinity, and nutrient front separates these water masses. The front is oriented along the north-south direction, located on average near the 50 m isobath at 32°S and extends southward toward the shelf break near 36°S. Between 32° and 34°S the Subtropical Shelf Front follows the 100 to 200 m isobaths and separates Subantarctic Shelf Water from the oceanic South Atlantic Central Water. On the basis of the temperature and salinity distributions, beneath the low-salinity surface layer, the Subtropical Shelf Front appears as an extension of the Brazil-Malvinas Confluence over the continental shelf of South America. Thus the location of the Subtropical Shelf Front may be linked to the migrations of the separation point of the Brazil-Malvinas Confluence from the continental slope.

Piola, Alberto R.; Campos, Edmo J. D.; MöLler, Osmar O.; Charo, Marcela; Martinez, Carlos

2000-03-01

263

Cold Sores  

NSDL National Science Digital Library

This patient education program explains cold sores. It reviews signs, stages, infection, outbreaks, diagnosis and treatment options, as well as self-care and prevention. This is a MedlinePlus Interactive Health Tutorial from the National Library of Medicine, designed and developed by the Patient Education Institute. NOTE: The tutorial requires a special Flash plug-in, version 4 or above. If you do not have Flash, you will be prompted to obtain a free download of the software before you start the tutorial. You will also need an Acrobat Reader, available as a free download, in order to view the Reference Summary.

Patient Education Institute

264

Climatology and variability of Southern Hemisphere marine cold-air outbreaks  

NASA Astrophysics Data System (ADS)

Marine cold air outbreaks (MCAOs) are events where cold air flows over a relatively warm sea surface. Such outbreaks are associated with severe mesoscale weather systems that are not generally resolved in global climate models, such as polar lows and boundary-layer fronts. Here, an analysis of winter climatology and variability of MCAOs in the Southern Hemisphere (SH) is presented. Near the sea ice edge, north-south fluctuations of the Southern Annular Mode (SAM) index are key, while further north, large-scale wave disturbances are needed to move air masses far enough away from the Antarctic continent to instigate MCAOs. Unlike in the Northern Hemisphere (NH), the spatial patterns of mean and extreme values of the MCAO index differ considerably. Near 60°S, both mean and extreme values of the index are similar to those found in the main MCAO regions in the NH. Further north, the mean MCAO index is quite high, but the extreme values are much lower than in the NH. We conclude that MCAOs in the SH are as widespread and can be as strong as in the NH, but severe MCAOs near densely populated regions such as the Tasman Sea are less common than in the Nordic Seas and near Japan.

Bracegirdle, Thomas J.; Kolstad, Erik W.

2010-03-01

265

Taxonomy of Greater White-fronted Geese (Aves: Anatidae)  

USGS Publications Warehouse

Five subspecies of the Greater White-fronted Goose, Anser albifrons (Scopoli, 1769), have been named, all on the basis of wintering birds, and up to six subspecies have been recognized. There has been confusion over the application of some names, particularly in North America, because of lack of knowledge of the breeding ranges and type localities, and incorrect taxonomic decisions. There is one clinally varying subspecies in Eurasia, one that breeds in Greenland, and three in North America, one newly named herein.

Banks, Richard C.

2011-01-01

266

Simulations of hydrologically significant winter storms over a mountainous watershed  

Microsoft Academic Search

The largest watershed-to-basin-scale flood events in the Inland Pacific Northwest have typically occurred with a fairly rapid transition from anomalously cold to anomalously warm weather in the winter or early spring months. A research study has been conducted to analyze and simulate the variability of precipitation and snow distribution associated with these floods on a watershed scale. A goal of

Dahong Wang

1997-01-01

267

Crow deaths caused by West Nile virus during winter.  

PubMed

In New York, an epizootic of American crow (Corvus brachyrhynchos) deaths from West Nile virus (WNV) infection occurred during winter 2004-2005, a cold season when mosquitoes are not active. Detection of WNV in feces collected at the roost suggests lateral transmission through contact or fecal contamination. PMID:18258045

Dawson, Jennifer R; Stone, Ward B; Ebel, Gregory D; Young, David S; Galinski, David S; Pensabene, Jason P; Franke, Mary A; Eidson, Millicent; Kramer, Laura D

2007-12-01

268

Winter 2014 Economics 471  

E-print Network

Winter 2014 Economics 471: Public Finance Government Finance -- Syllabus Winter 2014 1 US Treasury intervention in the market. After covering basic prin- ciples of public finance, we will focus on the taxing Textbook: Public Finance and Public Policy (4th Edition) by Jonathan Gruber. Available at the bookstore

Carter, John

269

Winter Olympic Sports  

NSDL National Science Digital Library

Exploring Winter Olympic Sports Let's take a look at some of the different winter olympic sports Alpine Skiing Biathalon Bobsleigh Cross country Curling Figure Skating Freestyle skiing Ice Hockey Luge Nordic Combined Short track speed skating Skeleton Ski Jumping Snowboard Speed Skating ...

Mrs. Keller

2010-01-23

270

Winter 2013 + Dream scholarships  

E-print Network

Winter 2013 + Dream scholarships + Autism spectrum disorder + Teen sleep + 2011-12 donor roster from around CEHD 6 research highlights Autism spectrum disorder, resilience, concussions, and more 20 of tested federal TRiO programs 18 a long winter's nap Q&A with Kyla Wahlstrom about teen sleep, school

Ciocan-Fontanine, Ionut

271

Bison in Winter  

USGS Multimedia Gallery

A plains bison in winter at Yellowstone National Park. A bison's hump is useful as a snowplow in winter when the animal swings its head from side to side to brush aside the snow to reach food underneath. The hump is composed of muscles supported by long vertebrae....

272

Winter Math Activities  

NSDL National Science Digital Library

This webpage of winter math activities includes seasonal activities for patterns, graphing, symmetry, estimations, and glyphs. Other resources on this page include literature connections, links to more winter resources, and pictures of student work. Activities are centered on penguins, snowflakes, snowman, and gingerbread.

Terry Kawas

2013-01-01

273

Winter Art Education Project  

ERIC Educational Resources Information Center

The purpose of this article is to describe how the Department of Art Education at the University of Lapland in Finland has developed winter art as a method of environmental and community-based art education. I will focus on the Snow Show Winter Art Education Project, a training project funded by the European Union and the State Provincial Office…

Jokela, Timo

2007-01-01

274

Winter, Your Car, and You  

MedlinePLUS

... Toggle navigation Public News and Resources – Winter Your Car and You Winter, Your Car and You Start with a checkup that includes: ... a car shut. News and Resources – Winter Your Car and You Get the Facts This page is ...

275

Front Range Branch Officers  

NASA Astrophysics Data System (ADS)

The Front Range Branch of AGU has installed officers for 1990: Ray Noble, National Center for Atmospheric Research, chair; Sherry Oaks, U.S. Geological Survey, chair-elect; Howard Garcia, NOAA, treasurer; Catharine Skokan, Colorado School of Mines, secretary. JoAnn Joselyn of NOAA is past chair. Members at large are Wallace Campbell, NOAA; William Neff, USGS; and Stephen Schneider, NCAR.

276

Front motion Dirk Blomker  

E-print Network

in the one-dimensional stochastic Cahn-Hilliard equation Dirk Bl¨omker joint work with : Dimitra AntonopoulouFront motion Dirk Bl¨omker Introduction spinodal decomposition Metastability stochastic Cahn-Hilliard decomposition Metastability stochastic Cahn-Hilliard Slow manifold Construction deterministic Attraction

Mörters, Peter

277

[Revealing hereditary variation of winter hardiness in cereals].  

PubMed

A set of cereal crops and differentiating cultivars was shown to be of utility for identifying the major abiotic factors that limit the survival of winter crops in the cold season of a particular year. With this approach, the season was identified (1997-1998, Belgorod) when the survival of cereals depended on the tolerance to anaerobiosis rather than on the frost resistance. Differentiation of common wheat cultivars with respect to this property was attributed to a locus designated Win1 (Winter hardiness 1) and localized 3.2-5.8% recombination away from the B1 (awnlessness) gene. Winter barley (cultivar Odesskii 165) displayed the highest tolerance to anaerobiosis in the cold season; low and intermediate tolerance was established for winter durum wheat (cultivar Alyi Parus) and winter common wheat, respectively. Frost resistance and winter hardiness type 1 proved to be determined by different genetic systems, which showed no statistical association. Correlation analysis revealed significant positive associations of frost resistance in the field (1996-1997, Belgorod) with productivity, sedimentation index, plant height, and vegetation period in wheat. Statistical analysis associated frost resistance with gliadin-coding alleles of homeologous chromosomes 1 and 6 of the A, B, and D wheat genomes. PMID:15612569

Netsvetaev, V P; Netsvetaeva, O V

2004-11-01

278

Winter habitat selection by a montane forest bird assemblage: the effects of solar radiation  

Microsoft Academic Search

A relationship between sunlight and bird abundance in cold climates may seem intuitive and perhaps obvi- ous. However, there is, surprisingly, little or no evidence to support it. We investigated the effects of solar radiation on the winter abundance of insectivorous birds inhabiting a Mediterranean montane forest with a high frequency of cold, cloudless days. We censused birds by ear

Daniel L. Huertas; José A. Díaz

2001-01-01

279

Logistic regression analysis of the response of winter wheat to components of artificial freezing episodes  

Technology Transfer Automated Retrieval System (TEKTRAN)

Improvement of cold tolerance of winter wheat (Triticum aestivum L.) through breeding methods has been problematic. A better understanding of how individual wheat cultivars respond to components of the freezing process may provide new information that can be used to develop more cold tolerance culti...

280

Variation in the Hatteras Front density and velocity structure Part 2: Historical setting  

NASA Astrophysics Data System (ADS)

On the continental shelf near Cape Hatteras, cool fresh Mid-Atlantic Bight and warm salty South Atlantic Bight shelf waters converge alongshelf 90% of the time, causing strong alongshelf gradients in temperature and salinity known as the 'Hatteras Front'. The resulting density gradient supports strong shoreward velocities in the cross-shelf oriented 'nose', of the Front in wintertime. To investigate further, the Frontal Interactions near Cape Hatteras (FINCH) project used shipboard ADCP and a towed undulating CTD to examine Hatteras Front property, density and velocity fields in August 2004, January 2005, and July 2005. Strong property gradients were encountered across the nose of the Hatteras Front in all cases, but the density gradient, dynamic height gradient, and observed along-front cross-shelf velocities evolved in time. FINCH along-Front velocities were strong and shoreward in fall and winter, and weakly mixed shoreward and seaward in July. Several archived data sets were examined, and demonstrate that the density evolution and wind forcing seen in FINCH are characteristic of other years. Evidence suggests the width of the Hatteras Front does not vary dramatically in time, so that consistently large fall and winter density contrast across the Front implies consistently large shoreward velocities along it in winter. Weak density contrasts across the Hatteras Front in spring suggest the magnitude and sign of springtime density gradients and along-Front velocities could vary interannually. Recruitment success of commercially important stocks on the shelf that depend on cross-shelf transport may thus be affected year to year.

Savidge, Dana K.; Austin, Jay A.; Blanton, Brian O.

2013-02-01

281

9. DETAIL OF INTERIOR OF FRONT PORCH SHOWING FRONT ENTRY ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. DETAIL OF INTERIOR OF FRONT PORCH SHOWING FRONT ENTRY (LEFT) AND BLANK WALL (CENTER) CORRESPONDING TO LOCATION OF INTERIOR VAULTS. VIEW TO SOUTHEAST. - Boise Project, Boise Project Office, 214 Broadway, Boise, Ada County, ID

282

3. VIEW NORTH, SOUTHWEST FRONT, SOUTHEAST SIDE Front and side ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. VIEW NORTH, SOUTHWEST FRONT, SOUTHEAST SIDE Front and side elevation. Note gasoline sign post added. Flush store window not altered, 1900 clapboard siding and panelling remaining. - 510 Central Avenue (Commercial Building), Ridgely, Caroline County, MD

283

35. EAST FRONT OF POWERHOUSE AND CAR BARN: East front ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

35. EAST FRONT OF POWERHOUSE AND CAR BARN: East front of powerhouse and car barn. 'Annex' is right end of building. - San Francisco Cable Railway, Washington & Mason Streets, San Francisco, San Francisco County, CA

284

Over the counter medicines for colds  

Microsoft Academic Search

Over the counter (OTC) medicines may be defined as medicines that are freely available to the public without a prescription\\u000a from a doctor. Self-medication for common cold is now encouraged by most government health authorities in order not to overload\\u000a health resources in winter. This chapter examines the efficacy of the different groups of medicines for the relief of common

Ronald Eccles

285

Bronchitis (Chest Cold)  

MedlinePLUS

... Antibiotic Use Respiratory Illnesses Sinus Infection Sore Throat Common Cold and Runny Nose Ear Infections Bronchitis (Chest Cold) ... Tips Appropriate Treatment Summary Cough Illness/Bronchitis The Common Cold Otitis Media Pharyngitis: Treat Only Proven GAS Online ...

286

Cold knife cone biopsy  

MedlinePLUS

A cold knife cone biopsy (conization) is surgery to remove a sample of abnormal tissue from the cervix. The cervix is ... Cold knife cone biopsy is done to detect cervical cancer or early changes that lead to cancer. A cold ...

287

Are summit metabolism and thermogenic endurance correlated in winter-acclimatized passerine birds?  

PubMed

Small birds exhibiting marked winter improvement of cold tolerance also show elevated summit metabolic rates (maximum cold-induced metabolic rate) in winter relative to summer. However, relatively large increases in cold tolerance can occur with only minor increments of maximum cold-induced metabolic rate and geographic variation in cold tolerance is not always positively correlated with variation in maximum cold-induced metabolic rate. Thus, it is uncertain whether maximum cold-induced metabolic rate and cold tolerance are phenotypically correlated in small birds and no previous study has directly examined this relationship. I measured maximum cold-induced metabolic rate and cold tolerance (i.e., thermogenic endurance) over three winters in black-capped chickadees Poecile atricapillus, American tree sparrows Spizella arborea, and dark-eyed juncos Junco hyemalis. For raw thermogenic endurance data, residuals of maximum cold-induced metabolic rate and thermogenic endurance from mass regressions were significantly and positively correlated in juncos and tree sparrows, and their correlation approached significance for chickadees. Log10 transformation of thermogenic endurance and mass data gave similar results. These data provide the first direct evidence for a phenotypic correlation between maximum cold-induced metabolic rate and thermogenic endurance in small birds, although much of the variance in thermogenic endurance is explained by factors other than maximum cold-induced metabolic rate and the degree of correlation differs among species. Nevertheless, these data suggest that physiological adjustments producing elevated thermogenic endurance also produce elevated maximum cold-induced metabolic rate in small birds. PMID:11585259

Swanson, D L

2001-08-01

288

Landfalling Fronts and Cyclones  

NSDL National Science Digital Library

Landfalling cyclones and their attendant fronts significantly impact the structure of mesoscale wind and precipitation fields along the west coast of North America. This module focuses on the complex interaction of the wind field with topography and the resulting effects on nearshore winds and precipitation. For example, prefrontal conditions may lead to flow blocking, development of a barrier jet, and seaward displacement of the maximum precipitation. Postfrontal conditions tend to promote windward ridging and lee troughing, which enhance along-coast flow.

COMET

2006-05-24

289

Today's Front Pages  

NSDL National Science Digital Library

Readers curious about how newspapers around the nation and the world are covering events during these difficult times may find this site useful. From the Newseum, this resource provides expandable thumbnails of front pages from September 12, 2001 newspapers from around the world. The Newseum is an interactive museum devoted to journalism and sponsored by the Freedom Forum, "a nonpartisan, international foundation dedicated to free press, free speech and free spirit for all people" (see the January 14, 2000 Scout Report).

290

Cold Atoms  

NASA Astrophysics Data System (ADS)

This chapter and the following one address collective effects of quantum particles, that is, the effects which are observed when we put together a large number of identical particles, for example, electrons, helium-4 or rubidium-85 atoms. We shall see that quantum particles can be classified into two categories, bosons and fermions, whose collective behavior is radically different. Bosons have a tendency to pile up in the same quantum state, while fermions have a tendency to avoid each other. We say that bosons and fermions obey two different quantum statistics, the Bose-Einstein and the Fermi-Dirac statistics, respectively. Temperature is a collective effect, and in Section 5.1 we shall explain the concept of absolute temperature and its relation to the average kinetic energy of molecules. We shall describe in Section 5.2 how we can cool atoms down thanks to the Doppler effect, and explain how cold atoms can be used to improve the accuracy of atomic clocks by a factor of about 100. The effects of quantum statistics are prominent at low temperatures, and atom cooling will be used to obtain Bose-Einstein condensates at low enough temperatures, when the atoms are bosons.

Bellac, Michel Le

2014-11-01

291

Expansion of a cold non-neutral plasma slab  

NASA Astrophysics Data System (ADS)

Expansion of the ion and electron fronts of a cold non-neutral plasma slab with a quasi-neutral core bounded by layers containing only ions is investigated analytically and exact solutions are obtained. It is found that on average, the plasma expansion time scales linearly with the initial inverse ion plasma frequency as well as the degree of charge imbalance, and no expansion occurs if the cold plasma slab is stationary and overall neutral. However, in both cases, there can exist prominent oscillations on the electron front.

Karimov, A. R.; Yu, M. Y.; Stenflo, L.

2014-12-01

292

Winter Storm Fire Safety  

MedlinePLUS

... electrical fires. Encourage safe holiday decoration displays, including candles. Suggest ways to safely cook indoors. Outreach materials ... fire #safetytip: always use a flashlight - not a candle - for emergency lighting. Facebook During a winter storm, ...

293

The Winter Is Past.  

ERIC Educational Resources Information Center

Teacher, writer, and naturalist Phyllis S. Busch takes the reader on an early evening woodland walk in March, describing the many changes in plants and animals that are perceptible by sight, smell, and sound as nature awakens from winter. (NEC)

Busch, Phyllis S.

1985-01-01

294

Water transport under winter conditions  

Microsoft Academic Search

Winter as well as summer floods result in soil loss and sedimentation. Up to now the winter events cannot be adequately predicted. This paper focuses on the infiltration processes under frozen winter conditions in order to model soil erosion processes in winter by adapting the computer model EROSION 3D [Schmidt, J., Werner, M. v., 2000. Modeling Sediment and Heavy Metal

Astrid Weigert; Jürgen Schmidt

2005-01-01

295

Science of Winter  

NSDL National Science Digital Library

Is it true that no two snowflakes are alike? What happens to mosquitoes when the mercury drops? National Geographic Channel explores the planet's most extreme season. This engaging three-minute video discusses the astronomical basis for winter, and other seasons, based on the angle of incidence of the sun's rays relative to the Northern and Southern Hemispheres, as well as the components of intense winter storms.

296

Winter Storm Activity  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Weather affects our everyday lives. Some days it's sunny and some days its not. The years weather is split up into seasons. 1. What are the four seasons? 2. What kind of weather do you see in the summer? 3. What kind of weather is unique to winter? 4. What ...

Jennifer Haight

2010-02-22

297

Arctic-Winter Climatology and Radiative Effects of Clouds and Aerosols Based on Lidar and Radar Measurements at PEARL  

E-print Network

Measurements at PEARL T. Ayash, J.-P. Blanchet and E. W. Eloranta During the cold and dark Polar winter months Laboratory (PEARL) at Eureka, Nunavut by an Automated High Spectral Resolution Lidar (AHSRL

Eloranta, Edwin W.

298

Cold-Weather Sports  

MedlinePLUS

Ahh, winter! Shorter days. Frigid temperatures. Foul weather. What better time to be outdoors? Winter sports can help you burn calories, increase your cardiovascular fitness, and strengthen muscles. Activities that are ...

299

Long-term variability of cold surges in Korea  

NASA Astrophysics Data System (ADS)

Cold surge statistics have been analyzed from the 52-year (1961-2012) winter temperature data archived at Korea Meteorological Administration. Despite a significant winter warming in South Korea, there is no statistically affirmable sign of the occurrence frequency, duration and total days of cold surges to have changed in the record; there is little abatement in the frequency, duration, and total days of cold surges. Thermal advection anomalies were also derived from the NCEP/NCAR and ERA interim reanalysis datasets. Cold surges defined in terms of thermal advection anomalies do not exhibit any statistically significant change either. The increased mean and the decreased variance of thermal advection both indicate that cold advection from north has, in fact, decreased gradually in South Korea. It appears that cold surges are statistically rare enough to be affected by increased mean and decreased variance of thermal advection. Polar warming is often interpreted as weakening of jet stream and increasing southward flux of cold air. Analysis of thermal advection, on the other hand, does not show increased advection of cold air from north in South Korea.

Kim, Kwang-Yul; Lee, Seoyeon; Kim, Maeng-Ki; Cho, Chun-Ho

2014-08-01

300

Nuclear Winter: The implications for civil defense  

SciTech Connect

''Nuclear Winter'' is the term given to hypothesized cooling in the northern hemisphere following a nuclear war due to injection of smoke from burning cities into the atmosphere. The voluminous literature on this subject produced since the original paper in 1983 by Turco, Toon, Ackerman, Pollack, and Sagen (TTAPS) has been reviewed. The widespread use of 3-dimensional global circulation models have resulted in reduced estimates of cooling; 15 to 25/sup 0/C for a summer war and a few degrees for a winter war. More serious may be the possibility of suppression of convective precipitation by the altered temperature profiles in the atmosphere. However, very large uncertainties remain in input parameters, the models, and the results of calculations. We believe the state of knowledge about nuclear winter is sufficiently developed to conclude: Neither cold nor drought are likely to be direct threats to human survival for populations with the wherewithal to survive normal January temperatures; The principal threat from nuclear winter is to food production, and could present problems to third parties without food reserves; and Loss of a crop year is neither a new nor unexpected threat from nuclear war to the US and the Soviet Union. Both have at least a year's food reserve at all times. Both face formidable organizational problems in distributing their reserves in a war-damaged environment. The consequences of nuclear winter could be expected to fall more heavily on the Soviet Union than the US due to its higher latitude and less productive agriculture. This may be especially true if disturbances of rainfall amounts and distribution persist for more than a year. 6 refs.

Chester, C.V.; Perry, A.M.; Hobbs, B.F.

1987-01-01

301

HYPOTHERMIA Surviving the Cold  

E-print Network

), and fatigue are some of the main factors that can contribute to hypothermia. · Cold is the most common causeHYPOTHERMIA Surviving the Cold www.WorkSafebc.com #12;About the WCB Preventing on-the-job injury-HELP) toll-free in British Columbia. #12;1 Introduction Working in a cold environment ­ whether it be cold

Machel, Hans

302

Simple front tracking  

SciTech Connect

A new and simplified front tracking algorithm has been developed as an aspect of the extension of this algorithm to three dimensions. Here the authors emphasize two main results: (1) a simplified description of the microtopology of the interface, based on interface crossings with cell block edges, and (2) an improved algorithm for the interaction of a tracked contact discontinuity with an untracked shock wave. For the latter question, they focus on the post interaction jump at the contact, which is a purely 1D issue. Comparisons to other methods, including the level set method, are included.

Glimm, J.; Grove, J.W.; Li, X.; Zhao, N.

1999-04-01

303

Mechanisms for convection triggering by cold pools  

NASA Astrophysics Data System (ADS)

Cold pools are fundamental ingredients of deep convection. They contribute to organizing the subcloud layer and are considered key elements in triggering convective cells. It was long known that this could happen mechanically, through lifting by the cold pools' fronts. More recently, it has been suggested that convection could also be triggered thermodynamically, by accumulation of moisture around the edges of cold pools. A method based on Lagrangian tracking is here proposed to disentangle the signatures of both forcings and quantify their importance in a given environment. Results from a simulation of radiative-convective equilibrium over the ocean show that parcels reach their level of free convection through a combination of both forcings, each being dominant at different stages of the ascent. Mechanical forcing is an important player in lifting parcels from the surface, whereas thermodynamic forcing reduces the inhibition encountered by parcels before they reach their level of free convection.

Torri, Giuseppe; Kuang, Zhiming; Tian, Yang

2015-03-01

304

Climatological characteristics of fronts in the western North Pacific based on surface weather charts  

NASA Astrophysics Data System (ADS)

Composite front climatology in the western North Pacific is determined using a newly developed 1.0° gridded data set. Here we propose a research strategy for determining the spatiotemporal distribution of fronts using weather chart images published by the Japan Meteorological Agency, one of the major data providers in the region. A preliminarily investigation of the internal data characteristics for the period of 2000-2010 is undertaken, and the final 4 years of data are used for an analysis of front climatology to avoid the effect of any spurious trends. This enables in-depth analyses to be conducted, which have not previously been possible in the region, including the composites of cross-sectional patterns for the thermal fields and precipitation near fronts, front length seasonality, and the significance of the thermal gradient near the fronts, in addition to determining the frontal frequency and spatial distribution of frontal precipitation. Pixel-wise analysis reveals that 56% of the local precipitation maximum is located on the warm side of a cold front caused by less tilted upward motion on the warm side, with the intrusion of the upper level cold dry air into the warm side. This new data set also enables a further analysis of the occluded fronts, which are not correctly distinguished in the existing objective detection method.

Utsumi, Nobuyuki; Kim, Hyungjun; Seto, Shinta; Kanae, Shinjiro; Oki, Taikan

2014-08-01

305

Application of an atmospheric dispersion model to simulated pollutant releases in the Colorado Front range  

Microsoft Academic Search

The 1991 ASCOT (Atmospheric Studies in Complex Terrain) field study in the vicinity of the Department of Energy`s Rocky Flats Plant, Colorado, was conducted to study the local and regional circulations and their interactions with synoptic flows over the complex terrain of the Rocky Mountains Colorado Front range. The study was combined with the Rocky Flats Winter validation Study (WVS)

1993-01-01

306

Spring Staging Areas of the Greenland White-fronted Goose (Anser albifrons flavirostris) in West Greenland  

Microsoft Academic Search

The Greenland white-fronted goose (Anser albifrons flavirostris) migrates about 3000 km from wintering grounds in Ireland and Britain to breeding grounds in West Greenland (64? - 72?N). The migration route includes long flights over the ocean and over the Greenland ice cap. To obtain optimal reproduction output, it is important for the geese to build up their condition at specific

CHRISTIAN M. GLAHDER

1999-01-01

307

BREEDING POPULATIONS OF TULE WHITE-FRONTED GEESE IN NORTHWESTERN CANADA  

Microsoft Academic Search

HE Tule White-fronted Goose (Anser albifrons gambelli) is one of the least known of the North American wild geese. Available information has been largely limited to observations and collected specimens of wintering birds. The migrational routes are virtually uncharted and breeding areas unknown. The basis for considering gambelli to be a valid subspecies is dis- cussed by Swarth and Bryant

BOB ELCAS

308

Factors affecting rice grain density unconsumed by white-fronted geese in relation to wheat damage  

Microsoft Academic Search

Lake Miyajimanuma, in central Hokkaido, is an important stopover site for white-fronted geese (Anser albifrons) wintering in Japan. In this area, increasing numbers of the geese are causing damage to wheat crops. The effects of several factors on the unconsumed density of food resources in rice fields, their main foraging site, were investigated with a view to propose a method

Tatsuya Amano; Katsumi Ushiyama; Go Fujita; Hiroyoshi Higuchi

2004-01-01

309

EFFECTS OF CLIMATE CHANGE ON VEGETATION AND ECOSYSTEM SERVICES IN THE COLORADO FRONT RANGE  

EPA Science Inventory

If climate change leads to an extended growing season and somewhat wetter winters in the Front Range of Colorado, then a new time period of resource availability will be created. Non-native vegetation whose native lands possessed climates similar to the ?new conditions? may be...

310

Winter ecology of Arctic charr ( Salvelinus alpinus ) and brown trout ( Salmo trutta ) in a subarctic lake, Norway  

Microsoft Academic Search

We studied habitat choice, diet, food consumption and somatic growth of Arctic charr (Salvelinus alpinus) and brown trout (Salmo trutta) during the ice-covered winter period of a subarctic lake in northern Norway. Both Arctic charr and brown trout predominantly\\u000a used the littoral zone during winter time. Despite very cold winter conditions (water temperature <1°C) and poor light conditions,\\u000a both fish

Per-Arne Amundsen; Rune Knudsen

2009-01-01

311

Frost resistance and biochemical changes during cold acclimation in different annual legumes  

Microsoft Academic Search

In Mediterranean areas of southern Europe growth of forages is seriously limited by the ability of each species to growth during cold winter. Therefore, the objective of this work was to prove the capacity for cold acclimation and frost resistance in four annual legumes native of Mediterranean region under laboratory conditions. Plants from subterranean clover (Trifolium subterraneum L. ssp. brachycalycinum

Marta Hekneby; M. Carmen Antolín; Manuel Sánchez-Díaz

2006-01-01

312

Cold tolerance of forage legumes growing in controlled continental Mediterranean conditions  

Microsoft Academic Search

Summary - The growth of forage crops in Mediterranean areas is seriously limited by the dry summer but also by the cold winter. Potential forage species should be tested to improve the forage availability in these periods in which herbage production is limited. The objectives of this study were to compare seedling survival and viability in response to cold conditions

M. Sánchez-Díaz; M. Hekneby; M. C. Antolín

313

Cold exposure increases running V O2 max and cost of transport in goats  

E-print Network

, although aerobic capacity was increased with acclimation to severe winter weather, cold-acclimated goats. Furthermore, given the high capacity of muscle for aerobic metabolism, muscle has a great capacity for heat these findings as evidence that cold is a sufficient stimulus to invoke the development of aerobic structures

Lindstedt, Stan

314

From the front  

SciTech Connect

The causes of recent dynamic thinning of Greenland's outlet glaciers have been debated. Realistic simulations suggest that changes at the marine fronts of these glaciers are to blame, implying that dynamic thinning will cease once the glaciers retreat to higher ground. For the last decade, many outlet glaciers in Greenland that terminate in the ocean have accelerated, thinned, and retreated. To explain these dynamic changes, two hypotheses have been discussed. Atmospheric warming has increased surface melting and may also have increased the amount of meltwater reaching the glacier bed, increasing lubrication at the base and hence the rate of glacier sliding. Alternatively, a change in the delicate balance of forces where the glacier fronts meet the ocean could trigger the changes. Faezeh Nick and colleagues5 present ice-sheet modeling experiments that mimic the observations on Helheim glacier, East Greenland, and suggest that the dynamic behaviour of outlet glaciers follows from perturbations at their marine fronts. Greenland's ice sheet loses mass partly through surface melting and partly through fast flowing outlet glaciers that connect the vast plateau of inland ice with the ocean. Earlier ice sheet models have failed to reproduce the dynamic variability exhibited by ice sheets over time. It has therefore not been possible to distinguish with confidence between basal lubrication from surface meltwater and changes at the glaciers' marine fronts as causes for the observed changes on Greenland's outlet glaciers. But this distinction bears directly on future sea-level rise, the raison d'etre of much of modern-day glaciology: If the recent dynamic mass loss Greenland's outlet glaciers is linked to changing atmospheric temperatures, it may continue for as long as temperatures continue to increase. On the other hand, if the source of the dynamic mass loss is a perturbation at the ice-ocean boundary, these glaciers will lose contact with that perturbation after a finite amount of thinning and retreat. Therefore, the first hypothesis implies continued retreat of outlet glaciers into the foreseeable future, while the second does not -- provided the bedrock topography prohibits a connection between the retreating glacier and the ocean. Nick and coauthors test the physical mechanisms implied in each hypotbesis in an innovative ice-flow model, and use that model to try to match a time series of observations from Helheim glacier, one of Greenland's three largest outlet glaciers. Along with many observations, the simulations strongly support the contention that the recent retreat of Greenland's outlet glaciers is the result of changes at their marine fronts.Further, the simulations confirm the earlier hypotheses that bedrock topography largely controlled Helheim glacier's rapid acceleration and retreat in 2004 and 2005, and its deceleration and stabilization in 2006. Finally, the current work implies that if requirements of observational data (high-resolution bed topography) and computational resources (fine computational grid resolution) can be met, improved predictive capability for ice-sheet models is attainable. With respect to the concerns raised by the IPCC, this study signals progress.

Price, Stephen [Los Alamos National Laboratory

2009-01-01

315

Close the Door--You're Letting the Cold In!  

NSDL National Science Digital Library

Actually no, you aren't letting the cold in when you leave the door open in winter. That's a common misconception that will be gently put to rest in this chapter. There will, however, be a discussion of the tranfer of energy that makes things hotter and colder.

William C. Robertson, Ph.D.

2002-01-01

316

Introduction Our world is a cold place. About 90% of  

E-print Network

biochemical adaptations. However, before we talk about how animals survive when environmental temperatures. Much of the land is even colder. Winter air temperatures in countries such as Canada or Russia often fall to -30 and, in the Arctic and Antarctic, -70 is not uncommon. How do animals survive the cold

Storey, Kenneth B.

317

IMPROVEMENT OF VARIETAL GARLIC VIABILITY BY COLD STORAGE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Garlic is a specialty horticultural crop that is usually planted in the fall and harvested in late summer. By delaying the planting until spring, high winter winds that blow away much needed mulch and irrigation operational challenges could be avoided. Cold storage trials were performed to determi...

318

COLD TEMPERATURE MOTOR VEHICLE EMISSIONS TESTING IN ALASKA  

EPA Science Inventory

A motor vehicle emissions testing study was conducted in Anchorage and Fairbanks during the winter of 1998-99 to collect actual measurements of initial idle emission rates. The study was performed for a sample of 111 automobiles and light-duty trucks under cold wintertime ambient...

319

Winter Storm Lesson Plan  

NSDL National Science Digital Library

The subject of this lesson is Winter Storms. The length will be approximately 55 minutes (~15 minutes for each of the three websites and ~10 minutes for the students to create their slideshows). The slideshows may be presented the following day if not enough time is available. This lesson is intended for 4th grade and is directed towards Standard 2 of the 4th grade science core curriculum. This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Winter Storms Connection to Standards: Utah Core Curriculum: Science Standard 2 (Students will understand that the elements of weather can be observed, measured, and recorded to make predictions and determine simple weather patterns.) NETS-T: 1. Facilitate and Inspire Student Learning and Creativity - Students will be using websites and situations that ...

Tasia S.

2010-09-23

320

The Fabled Maine Winter  

NSDL National Science Digital Library

No study of Maine weather would be complete without analysis of the year of 1816 - the year with no summer in an area from western Pennsylvania and New York, up through Quebec and across to Maine and the Canadian maritimes. In this five-unit lesson, students will investigate the causes and effects of the Fabled Maine Winter by exploring a variety of data sources. They will locate, graph, and analyze meteorological and climatological data for Portland, Maine, for more recent years to try to find one that most closely resembles the fabled Maine winter of 1816.

321

Winter Storm (weather)  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. First think about these questions: 1. What is your favorite aspect of winter weather? 2. How does the weather effect your everyday life? Form groups of THREE. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper... 1. In general, when are winds formed? 2. When winds are blowing, how can you ...

Aubree Miller

2009-09-28

322

VIEW OF FRONT, RECESSED ENTRY SHOWING FRONT WALK. VIEW FACING ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF FRONT, RECESSED ENTRY SHOWING FRONT WALK. VIEW FACING SOUTHWEST - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, Three-Bedroom Single-Family Type 9, Birch Circle, Elm Drive, Elm Circle, and Date Drive, Pearl City, Honolulu County, HI

323

Identifying Lagrangian fronts with favourable fishery conditions  

NASA Astrophysics Data System (ADS)

Lagrangian fronts (LFs) in the ocean are defined as boundaries between surface waters with strongly different Lagrangian properties. They can be accurately detected in a given velocity field by computing synoptic maps for displacements of synthetic tracers and other Lagrangian indicators. We use Pacific saury catch and location data for a number of commercial fishery seasons in the region of the northwest Pacific with one of the richest fishery in the world. It is shown statistically that the saury fishing grounds with maximal catches are not randomly distributed over the region but located mainly along the sharp LFs where productive cold waters of the Oyashio Current, warmer waters of the southern branch of the Soya Current, and waters of warm-core Kuroshio rings converge. Computation of those fronts in altimetric geostrophic velocity fields both in the years with the First and Second Oyashio Intrusions shows that in spite of different oceanographic conditions LF locations may serve as good indicators of potential fishing grounds. Possible biophysical reasons for saury aggregation near sharp LFs are discussed. We propose a mechanism for effective export of nutrient rich waters based on stretching of material lines in the vicinity of hyperbolic objects in the ocean. The developed method, based on identifying LFs in any velocity fields, is quite general and may be applied to find potential fishing grounds for the other pelagic fish.

Prants, S. V.; Budyansky, M. V.; Uleysky, M. Yu.

2014-08-01

324

The Physics Front  

NSDL National Science Digital Library

The Physics Front is a public service provided by the American Association of Physics Teachers (AAPT), with additional sponsorship from the National Science Foundation (NSF). Here, teachers can browse physics resources by topic (such as "conceptual physics" and "AP-Calculus"), learn about lesson plans via the "Lesson Plan Central" area, and check out the latest "Featured Resource." A simple search engine on the top of the homepage can be used to find items of particular interest, and the "Browse Collection" option provides an easy-to-use route to over eighty different subtopics, such as diffraction, statics of fluids, and atomic physics. Also, visitors can create a free membership registration, which allows them to rate materials, participate in discussions, and organize resources in a "personal filing cabinet." Additionally, visitors can sign up in the "Get Involved" section to become a peer-reviewer or a forum moderator for the site.

2012-06-22

325

Deciduous Plant Twigs in Winter  

ERIC Educational Resources Information Center

Describing, via illustration and narrative, the winter twigs found in the U.S., this article presents a sophisticated discussion of: beech, white ash, aspen, sycamore, red oak, butternut, and other winter twigs. (JC)

Clark, Eloise

1977-01-01

326

Winter Weather Introduction  

E-print Network

equipment. · Organize and implement CF-FO operational plans. · Review all procedures with CF-FO Managers the labor and equipment hours. #12;Campus Facilities-Energy Management · Clear the coal road and interiorWinter Weather Management #12;Introduction · Campus Facilities Staff · Other Campus Organizations

Taylor, Jerry

327

Announcement Cryptography { Winter 2001  

E-print Network

Announcement Cryptography { Winter 2001 A course in Cryptography is scheduled to be o#11;ered) and a computing course (AM 2120 or CS 2710 or CS 2602). Suggested Text: \\Cryptography { Theory and Practice, but doing so #12;rst requires a discussion of the discrete logarithm problem). 5. Public-Key Cryptography

deYoung, Brad

328

Winter and Specialty Wheat  

Microsoft Academic Search

Wheat is the most widely grown crop in the world. Winter wheat is primarily common wheat (2n = 6x = 42) which has extensive germplasm resources that are used in breeding, often for disease and insect resistance. Though\\u000a wheat can be used as a forage crop and its grain for animal feed, the primary uses of common wheat are to

P. Baenziger; R. Graybosch; D. Van Sanford; W. Berzonsky

329

GRAND RIVER Winter 2014  

E-print Network

GRAND RIVER POST SECONDARY BOARD NEWSLETTER Winter 2014 Issue 55 P.O. Box 339 Ohsweken ON, N0A 1M0-mail: info@grpseo.org Website: www.grpseo.org Grand River Post Secondary Board Members Brenda Davis (Chair TO TOMORROW Onkwehon:we with Grand River Territory lineage are empowered through higher education within

Thompson, Michael

330

PLCO News, Winter 2001  

Cancer.gov

PLCO News, Winter 2001 Cancer Information Service If you have a question about cancer, call and speak with a trained specialist at NCI's Cancer Information Service (CIS). The CIS operates a nationwide toll-free telephone hotline Monday-Friday, 9:00 a.m.

331

PLCO News, Winter 2001  

Cancer.gov

PLCO News, Winter 2001 Trial Update Enrollment goal: 148,000 Total enrollment (as of November 30, 2000): 152,139 Men enrolled: 75,565 Women enrolled: 76,574 Number of people enrolled at age: 55-59 49,944 60-64 47,058

332

WINTER 2014 Sustainability and  

E-print Network

WINTER 2014 Sustainability and Renewable Energy in Costa Rica January 4 - 14 Dr. James Hoffmann, Program Director Lecturer Sustainability Studies Program E-511 Melville Library Stony Brook, NY 11794 sustainability and renewable energy. Students will spend 11 days in Costa Rica to participate in site visits

Stephens, Graeme L.

333

Winter Here and Now.  

ERIC Educational Resources Information Center

This book contains a wide variety of winter-oriented ideas and activities that can be adapted to all elementary grade levels and can also be integrated into existing mathematics, science, social studies, and/or art programs. The activities aim to help students develop the skills of observation, appreciation, and problem solving as well as…

Finlay, Joy

334

Winter Playscape Dreaming  

ERIC Educational Resources Information Center

Winter, like all seasons, adds a new sense of mystery and discovery to the world of young children. It is the time when they can study snowflakes, find icicles, or observe the birds that share their yards. This article presents ideas and suggestions on how to plan a playscape. A playscape is a man-made seasonal playground for young children. It…

Keeler, Rusty

2006-01-01

335

Physical Oceanography Winter 2013  

E-print Network

Physical Oceanography Winter 2013 Andrew Thompson January 8, 2013 Lecture 1. Introduction This course presents an introduction to physical oceanography with a particular focus on ocean circulation. It is assumed that students taking this course have had limited prior exposure to oceanography or fluid dynamics

Thompson, Andrew

336

Seasonal variations in the responses of glycolytic intermediates of human erythrocytes to acute cold exposure  

NASA Astrophysics Data System (ADS)

Seven male students were studied to observe the effects of acute cold exposure (at 10°C for 60 min) on erythrocyte concentrations of glycolytic intermediates in summer and in winter. The subjects shivered slightly but frankly in both experiments. Significant decreases were observed in the concentrations of pyruvate and lactate during body cooling in summer, but not in winter. The lactate concentration remained significantly reduced 15 min after cold exposure. After 60 min of cold exposure in summer, a negative crossover point appeared to exist between phosphoenolpyruvate and pyruvate and erythrocyte pyruvate kinase activity showed a significant decrease. No seasonal difference was observed in the initial control values of the intermediates measured. From these results and the fact that glucose, pyruvate and lactate are evenly distributed between erythrocytes and plasma, it is likely that erythrocytes and skeletal muscles need less fuel substrate, glucose during cold exposure in winter than in summer, suggesting that an increased economy of energy for homeostasis is achieved.

Ohno, H.; Yahata, T.; Yamashita, K.; Kuroshima, A.

1988-03-01

337

Cold Stress and the Cold Pressor Test  

ERIC Educational Resources Information Center

Temperature and other environmental stressors are known to affect blood pressure and heart rate. In this activity, students perform the cold pressor test, demonstrating increased blood pressure during a 1- to 2-min immersion of one hand in ice water. The cold pressor test is used clinically to evaluate autonomic and left ventricular function. This…

Silverthorn, Dee U.; Michael, Joel

2013-01-01

338

Modeling cold tolerance in the mountain pine beetle, Dendroctonus ponderosae.  

PubMed

Cold-induced mortality is a key factor driving mountain pine beetle, Dendroctonus ponderosae, population dynamics. In this species, the supercooling point (SCP) is representative of mortality induced by acute cold exposure. Mountain pine beetle SCP and associated cold-induced mortality fluctuate throughout a generation, with the highest SCPs prior to and following winter. Using observed SCPs of field-collected D. ponderosae larvae throughout the developmental season and associated phloem temperatures, we developed a mechanistic model that describes the SCP distribution of a population as a function of daily changes in the temperature-dependent processes leading to gain and loss of cold tolerance. It is based on the changing proportion of individuals in three states: (1) a non cold-hardened, feeding state, (2) an intermediate state in which insects have ceased feeding, voided their gut content and eliminated as many ice-nucleating agents as possible from the body, and (3) a fully cold-hardened state where insects have accumulated a maximum concentration of cryoprotectants (e.g. glycerol). Shifts in the proportion of individuals in each state occur in response to the driving variables influencing the opposite rates of gain and loss of cold hardening. The level of cold-induced mortality predicted by the model and its relation to extreme winter temperature is in good agreement with a range of field and laboratory observations. Our model predicts that cold tolerance of D. ponderosae varies within a season, among seasons, and among geographic locations depending on local climate. This variability is an emergent property of the model, and has important implications for understanding the insect's response to seasonal fluctuations in temperature, as well as population response to climate change. Because cold-induced mortality is but one of several major influences of climate on D. ponderosae population dynamics, we suggest that this model be integrated with others simulating the insect's biology. PMID:17412358

Régnière, Jacques; Bentz, Barbara

2007-06-01

339

Lagrangian sources of frontogenesis in the equatorial Atlantic front  

NASA Astrophysics Data System (ADS)

Estimating the processes that control the north equatorial sea surface temperature (SST)-front on the northern edge of the cold tongue in the tropical Atlantic is a key issue for understanding the dynamics of the oceanic equatorial Atlantic and the West African Monsoon. Diagnosis of the frontogenetic forcings on a realistic high-resolution simulation was used to identify the processes involved in the formation and evolution of the equatorial SST-front. The turbulent forcing associated with the mixed-layer turbulent heat flux was found to be systematically frontolytic while the dynamic forcing associated with currents was found to be frontogenetic for the equatorial SST-front. Nevertheless, the low-frequency component of the turbulent forcing was frontogenetic and initiated the SST-front which was then amplified and maintained by the leading dynamic forcing. This forcing was mainly driven by the meridional convergence of the northern South Equatorial Current (nSEC) and the Guinea Current, which points out the essential role played by the circulation in the equatorial SST-front evolution. The quasi-biweekly variability of the equatorial SST-front and its forcings were found to be more strongly coupled to the wind energy flux (WEF) than to the surface wind stress. In fact the WEF controlled the convergence/divergence of the nSEC and Guinea Current and thus the meridional component of the leading dynamic forcing. The WEF explains the equatorial SST-front development better than the wind does because it is a coupled ocean-atmosphere process.

Giordani, Hervé; Caniaux, Guy

2014-09-01

340

Lagrangian sources of frontogenesis in the equatorial Atlantic front  

NASA Astrophysics Data System (ADS)

Estimating the processes that control the north equatorial sea surface temperature (SST)-front on the northern edge of the cold tongue in the tropical Atlantic is a key issue for understanding the dynamics of the oceanic equatorial Atlantic and the West African Monsoon. Diagnosis of the frontogenetic forcings on a realistic high-resolution simulation was used to identify the processes involved in the formation and evolution of the equatorial SST-front. The turbulent forcing associated with the mixed-layer turbulent heat flux was found to be systematically frontolytic while the dynamic forcing associated with currents was found to be frontogenetic for the equatorial SST-front. Nevertheless, the low-frequency component of the turbulent forcing was frontogenetic and initiated the SST-front which was then amplified and maintained by the leading dynamic forcing. This forcing was mainly driven by the meridional convergence of the northern South Equatorial Current (nSEC) and the Guinea Current, which points out the essential role played by the circulation in the equatorial SST-front evolution. The quasi-biweekly variability of the equatorial SST-front and its forcings were found to be more strongly coupled to the wind energy flux ( WEF) than to the surface wind stress. In fact the WEF controlled the convergence/divergence of the nSEC and Guinea Current and thus the meridional component of the leading dynamic forcing. The WEF explains the equatorial SST-front development better than the wind does because it is a coupled ocean-atmosphere process.

Giordani, Hervé; Caniaux, Guy

2014-12-01

341

Instability of Magnetized Ionization Fronts Surrounding H II Regions  

NASA Astrophysics Data System (ADS)

An ionization front (IF) surrounding an H II region is a sharp interface where a cold neutral gas makes the transition to a warm ionized phase by absorbing UV photons from central stars. We investigate the instability of a plane-parallel D-type IF threaded by parallel magnetic fields, by neglecting the effects of recombination within the ionized gas. We find that weak D-type IFs always have the post-IF magnetosonic Mach number {M}_M2 ? 1. For such fronts, magnetic fields increase the maximum propagation speed of the IFs, while reducing the expansion factor ? by a factor of 1 + 1/(2?1) compared to the unmagnetized case, with ?1 denoting the plasma beta in the pre-IF region. IFs become unstable to distortional perturbations owing to gas expansion across the fronts, exactly analogous to the Darrieus-Landau instability of ablation fronts in terrestrial flames. The growth rate of the IF instability is proportional linearly to the perturbation wavenumber, as well as the upstream flow speed, and approximately to ?1/2. The IF instability is stabilized by gas compressibility and becomes completely quenched when the front is D-critical. The instability is also stabilized by magnetic pressure when the perturbations propagate in the direction perpendicular to the fields. When the perturbations propagate in the direction parallel to the fields, on the other hand, it is magnetic tension that reduces the growth rate, completely suppressing the instability when {M}_M22 < 2/(2? 1 - 1). When the front experiences an acceleration, the IF instability cooperates with the Rayleigh-Taylor instability to make the front more unstable.

Kim, Jeong-Gyu; Kim, Woong-Tae

2014-12-01

342

Instability of Magnetized Ionization Fronts Surrounding H II Regions  

NASA Astrophysics Data System (ADS)

An ionization front (IF) surrounding an H II region is a sharp interface through which a cold neutral gas makes transition to a warm ionized phase by absorbing UV photons from central massive stars. We investigate the structure and stability of a plane-parallel D-type IF threaded by parallel magnetic fields. We find that weak D-type IFs always have the post-IF magnetosonic Mach number M_{M2} ? 1. For such fronts, magnetic fields increase the maximum propagation speed of the IFs, while reducing the expansion factor by a factor of 1+1/(2?_1) compared to the unmagnetized case, with ?_1 denoting the plasma beta in the pre-IF region. IFs become unstable to distortional perturbations due to gas expansion across the fronts, exactly analogous to the Darrieus-Landau instability of ablation fronts in terrestrial flames. The growth rate of the IF instability is proportional linearly to the perturbation wavenumber as well as the upstream flow speed. The IF instability is stabilized by gas compressibility and becomes completely quenched when the front is D-critical. The instability is also stabilized by magnetic pressure when the perturbations propagate in the direction perpendicular to the fields. When the perturbations propagate in the direction parallel to the fields, on the other hand, it is magnetic tension that reduces the growth rate, completely suppressing the instability when M_{M2}^2 < 2/(?_1 - 1). When the front experiences an acceleration, the IF instability cooperates with the Rayleigh-Taylor instability to make the front more unstable.

Kim, Jeong-Gyu; Kim, Woong-Tae

2015-01-01

343

Lightning Protection against Winter Lightning  

Microsoft Academic Search

Winter lightning, which occurs along the Sea of Japan coast, often damages transmission lines and distribution lines with the conventional lightning protection. These lines in mountainous areas suffer extensive damage from winter lightning. It is very important to investigate the features of lightning outages in detail to improve the lightning protection measures against winter lightning, therefore observations of lightning strokes

Hitoshi Sugimoto

2007-01-01

344

Winter Wilderness Travel and Camping.  

ERIC Educational Resources Information Center

Knowledge and skill are needed for safe and enjoyable travel and camping in the wilderness in winter. The beauty of snow and ice, reduced human use, and higher tolerance of animals toward humans make the wilderness attractive during winter. The uniqueness of winter travel presents several challenges that are not present in other seasons. Safety is…

Gilchrest, Norman

345

Vitamin C and colds  

MedlinePLUS

... popular belief that vitamin C can cure the common cold , the scientific evidence for this is conflicting. Large ... B. Vitamin C for preventing and treating the common cold. Cochrane Database Syst Rev . 2007 Jul 18;(3): ...

346

Cold and Cough Medicines  

MedlinePLUS

... What can you do for your cold or cough symptoms? Besides drinking plenty of fluids and getting ... medicines. There are lots of different cold and cough medicines, and they do different things. Nasal decongestants - ...

347

MHD Stability of Interstellar Medium Phase Transition Layers. I. Magnetic Field Orthogonal to Front  

NASA Astrophysics Data System (ADS)

We consider the scenario of a magnetic field orthogonal to a front separating two media of different temperatures and densities, such as cold and warm neutral interstellar gas, in a two-dimensional plane-parallel geometry. A linear stability analysis is performed to assess the behavior of both evaporation and condensation fronts when subject to incompressible, corrugational perturbations with wavelengths larger than the thickness of the front. We discuss the behavior of fronts in both super-Alfvénic and sub-Alfvénic flows. Since the propagation speed of fronts is slow in the interstellar medium (ISM), it is the sub-Alfvénic regime that is relevant, and magnetic fields are a significant influence on front dynamics. In this case, we find that evaporation fronts, which are unstable in the hydrodynamic regime, are stabilized. Condensation fronts are unstable, but for parameters typical of the neutral ISM the growth rates are so slow that steady-state fronts are effectively stable. However, the instability may become important if condensation proceeds at a sufficiently fast rate. This paper is the first in a series exploring the linear and nonlinear effects of magnetic field strength and orientation on the corrugational instability, with the ultimate goal of addressing outstanding questions about small-scale ISM structure.

Stone, Jennifer M.; Zweibel, Ellen G.

2009-05-01

348

The relationship between cytokinins and the amount of nitrogen in the wintering organs of herbaceous plants  

Microsoft Academic Search

The dynamics of cytokinin content and the total protein and nonprotein forms of nitrogen in tissues of wintering organs of\\u000a clary sage Salvia sclarea L. and cinquefoil Potentilla alba L. in abnormally cold (2005–2006 years) and abnormally warm (2006–2007 years) winters in Moscow have been studied. A direct\\u000a correlation between the content of total cytokinins and the total and protein

V. V. Kondrat’eva; O. V. Shelepova

2010-01-01

349

Changes in the East Asian Winter Monsoon under the AOGCM Global Warming Simulations  

Microsoft Academic Search

The East Asian winter monsoon (EAWM) consists of strong cold air outbreak along the climatological Aleutian low and the strong Siberian High over the Eurasian continent. It is the strongest wind system in the boreal winter. The effect of global warming on the EAWM is studied using 20 state-of-the-art Atmosphere-Ocean coupled General Ciirculation Models. In the previous study, Hori and

M. E. Hori

2008-01-01

350

Does the lack of vernalization requirement interfere with winter survival of oilseed rape plants?  

Microsoft Academic Search

Recent studies (Rapacz 1999) have shown that cultivars of spring-type oilseed rape are able to cold-acclimate to the level\\u000a comparable with winter cultivars, but only after prehardening which results both in the increase of photosynthetic activity\\u000a and in growth cessation. It is commonly known that under field conditions spring-type cultivars could not survive winter.\\u000a Present studies were undertaken to explain

Marcin Rapacz; Ewa Chilmonik

2000-01-01

351

Polar vortex conditions during the 1995–96 Arctic Winter: MLS CLO and HNO 3  

Microsoft Academic Search

Microwave Limb Sounder (MLS) measure- ments of lower stratospheric C10 and HNOa during the 1995-96 Arctic winter are presented. The 1995-96 Arc- tic winter was both colder and more persistently cold than usual, leading to an enhancement in lower strato- spheric C10 of greater magnitude, vertical extent, and duration than previously observed in the Arctic. Vortex concentrations of HNOa in

M. L. Santee; G. L. Manney; W. G. Read; L. Froidevaux; J. W. Waters

1996-01-01

352

Occurrence of large temperature inversion in the thermohaline frontal zone at the Yellow Sea entrance in winter and its relation to advection  

NASA Astrophysics Data System (ADS)

inversion (higher temperature at a deeper depth) in winter and its relation to advection were investigated by analyzing both conductivity-temperature-depth data in the southern Yellow Sea (YS) and northwestern East China Sea during the winter of 2002-2003 and time series data of temperature, salinity, and currents at a buoy station at the YS entrance. Significant temperature inversions occur predominantly along the thermohaline front at the YS entrance where the Cheju Warm Current Water (CWCW) and the cold coastal waters meet. In February 2003, on the northern frontal zone along 34°N where isotherms and isohalines declined downward to the north, particularly large inversions with temperature differences of larger than 2.0°C were observed to occur more in troughs than in the crests of the wave-like frontal meander where the cold Korean coastal water (KCW) advances farther southward. The inversion persisted until mid-April at the buoy station in the frontal zone, and both temperature and salinity showed simultaneous variations in the same manner. During episodic occurrences of large inversions, temperature and salinity decreased sharply in the upper layer, but increased concurrently in the lower layer. These episodic inversions were found to be closely related to the westward advection of the KCW in the upper layer and the northward advection of the CWCW in the lower layer. It is considered that these advections may play an important role in maintaining baroclinicity in the northern frontal zone, which is responsible for driving the westward transversal flow across the YS entrance.

Lie, Heung-Jae; Cho, Cheol-Ho; Jung, Kyung Tae

2015-01-01

353

Air-sea interaction over a thermal marine front in the Denmark Strait  

NASA Astrophysics Data System (ADS)

An investigation was conducted into air-sea interaction in the Denmark Strait, where a distinct thermal front separates warm North Atlantic water from the cold East Greenland Current. The field data consisted of ship weather station data and rawinsonde soundings from R/V Aranda's expedition in August-September 1993. The surface energy balance differed drastically between the warm and cold side of the front (net fluxes of 95 W m-2 upward and 82 W m-2 downward, respectively). The difference resulted mostly from the contradictory turbulent fluxes. The air temperature, humidity and wind speed showed more variation on the warm side of the front. Lower wind speeds were observed on the cold side. The cross-frontal differences in the air temperature and wind speed were largest during front-parallel flow, but those in the sensible and latent heat flux were largest during cross-frontal flow. During cases of air advection across the front, the modification in the air temperature was strongest with a low wind speed. Downwind of the front, the sensible heat flux strongly depended on the south-north wind component. The rawinsonde data revealed temperature inversions and low-level jets. The wind profile was affected by the combined effects of baroclinity, surface layer stability, and stratification through the atmospheric boundary layer. The surface heterogeneity caused by the sea surface temperature front resulted in the Schmidt paradox: the area-averaged sensible heat flux was upward, while the area-averaged air temperature exceeded the area-averaged surface temperature. A mosaic method, extended by estimates of the local wind speed over the warm and cold water side, was applicable to parameterizing the area-averaged sensible heat flux.

Vihma, Timo; Uotila, Juha; Launiainen, Jouko

1998-11-01

354

Managing coastal grazing marshes for breeding waders and over wintering geese: Is there a conflict?  

Microsoft Academic Search

The winter grazing intensities of brent geese Branta bernicla, pink-footed geese Anser brachyrhynchus, and white-fronted geese A. albifrons, and the breeding densities of lapwing Vanellus vanellus, redshank Tringa totanus and snipe Gallinago gallinago, were related to the environmental characteristics of 81 fields within an area of coastal grazing marshes on the north Norfolk coast. Those fields grazed most intensively by

J. A. Vickery; W. J. Sutherland; M. O'Brien; A. R. Watkinson; A. Yallop

1997-01-01

355

FalllWinter CELEBRATE WOMEN, the Women's Health Program at the UConn Health Center, recognizes  

E-print Network

FalllWinter 2002 #12;CELEBRATE WOMEN, the Women's Health Program at the UConn Health Center Women also offers health seminars, health screenings, and front-line information on women's health.celebrate.uchc.edu. Celebrate WOmen also offers a FREE women's health membership program. \\fJ UConn Health Center #12

Holsinger, Kent

356

Hypothermia: A Cold Weather Hazard  

MedlinePLUS

... cold air. But, not everyone knows that cold weather can also lower the temperature inside your body. ... cold it is where you are. Check the weather forecasts for windy and cold weather. Try to ...

357

Winter Storm Activity  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Form groups of three. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What usually happens when there is a large difference between the temperatures? 4. What happens when there ...

Mikel Barbieri

2012-02-13

358

Storm Winter Activity  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Form groups of three. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What usually happens when there is a large difference between the temperatures? 4. What happens when there ...

KateOlsen58

2009-09-28

359

Winter Storm Activity  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Form groups of three. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? What is a better indicator of moisture in the air? 4. What happens when there is low ...

Xuan

2010-02-22

360

Winter Storm Activity  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Form groups of three. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What usually happens when there is a large difference between the temperatures? 4. What happens when there ...

Kirsten Butcher

2008-09-26

361

Al's Winter Storm Activity  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Form groups of three. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What usually happens when there is a large difference between the temperatures? 4. What happens when there ...

Al

2010-02-22

362

Winter Storm Activity  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Form groups of three. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What usually happens when there is a large difference between the temperatures? 4. What happens when there ...

FerraraTechClassroom

2012-02-06

363

Winter weather activity  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Weather Maker Simulator Use the weather simulation above to answer the following questions in complete sentences on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What usually happens when there is a large difference between the temperatures? 4. What happens when there is high ...

Whitney Frankovic

2009-09-28

364

Winter Storm Warning  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Form groups of three. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What usually happens when there is a large difference between the temperatures? 4. What happens when there ...

2009-09-28

365

winter storm applicator  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Form groups of three. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper. 1. What causes the wind to blow. 2. When winds are blowing, how can you get them to stop? 3. What usually happens when there is a large difference between the temperatures? 4. What happens when there ...

cory jones

2009-09-28

366

The Anomalous Winter of 1783-1784: Was the Laki Eruption or an Analog of the 2009-2010 Winter to Blame?  

NASA Technical Reports Server (NTRS)

The multi ]stage eruption of the Icelandic volcano Laki beginning in June, 1783 is speculated to have caused unusual dry fog and heat in western Europe and cold in North America during the 1783 summer, and record cold and snow the subsequent winter across the circum-North Atlantic. Despite the many indisputable impacts of the Laki eruption, however, its effect on climate, particularly during the 1783.1784 winter, may be the most poorly constrained. Here we test an alternative explanation for the unusual conditions during this time: that they were caused primarily by a combined negative phase of the North Atlantic Oscillation (NAO) and an El Nino ]Southern Oscillation (ENSO) warm event. A similar combination of NAO ]ENSO phases was identified as the cause of record cold and snowy conditions during the 2009.2010 winter in Europe and eastern North America. 600-year tree-ring reconstructions of NAO and ENSO indices reveal values in the 1783.1784 winter second only to their combined severity in 2009.2010. Data sources and model simulations support our hypothesis that a combined, negative NAO ]ENSO warm phase was the dominant cause of the anomalous winter of 1783.1784, and that these events likely resulted from natural variability unconnected to Laki.

D'Arrigo, Rosanne; Seager, Richard; Smerdon, Jason E.; LeGrande, Allegra N.; Cook, Edward R.

2011-01-01

367

Staying Warm Winter Experiments  

NSDL National Science Digital Library

These experiments use simple materials to prove that a lot of one's body heat escapes from one's head and that wearing a hat stops some of this heat loss. In addition, students consider how sitting directly on cold ground will cause one to lose heat faster than sitting on insulating material.

368

A cold regions automatic weather station  

NASA Astrophysics Data System (ADS)

Few meteorological measurements are available from mountainous or arctic areas because of the difficulty of operating instruments in these environments. The development of an automatic weather station (AWS) capable of measuring the standard meteorological variables and able to operate (using minimal power) in conditions of heavy riming and high winds is described. The summit of Cairn Gorm (1246 m a.m.s.l.) was used as the test site because it has a harsh cold winter climate and is relatively accessible from Wallingford.

Strangeways, I. C.

1985-07-01

369

[The relationship between cytokines and the amount of nitrogen in the wintering organs of herbaceous plants].  

PubMed

The dynamics of cytokine content and the total protein and nonprotein forms of nitrogen in tissues of wintering organs of clary sage Salvia sclarea L. and cinquefoil Potentilla alba L. in abnormally cold (2005-2006 years) and abnormally warm (2006-2007 years) winters in Moscow have been studied. A direct correlation between the content of total cytokines and the total and protein nitrogen forms in tissues of wintering leaves and buds has been determined. A correlation link between the level of single cytokines and the protein nitrogen forms has been found. PMID:21268866

Kondrat'eva, V V; Shelepova, O V

2010-01-01

370

Coastal dynamics off Northwest Iberia during a stormy winter period  

NASA Astrophysics Data System (ADS)

The consequences of a stormy winter period (2009/2010) on the shelf and coastal dynamics off Northwest Iberia are analysed by using model results in combination with the set of available observations in the frame of the Iberian Margin Ocean Observatory (RAIA), a cross-border infrastructure among North Portugal and Galicia (Spain). During the study winter, the frequent arrival of weather fronts forced river plumes to flow along the inner shelf in a fast (>1 m s-1) jet-like structure. The buoyant current strongly influenced the outer rías, the name of the estuaries in the region, where a strong decay of surface salinity (<10.5) has been observed. Once the weather front has passed, the wind reversal forced the offshore expansion of river plumes and also the development of a winter upwelling event. Thermohaline patterns in both model and observations revealed an intrusion of warm (>15 °C) and salty (>35.9) waters into the rías associated with the Iberian Poleward Current. Finally, some Lagrangian modelling experiments were performed to analyse the transport ability of the plume and the effect that could have had in the biological material trapped on it. The experiments reveal that an overall northward displacement of surface particles will be expected after several alternate wind events.

Otero, Pablo; Ruiz-Villarreal, Manuel; García-García, Luz; González-Nuevo, Gonzalo; Cabanas, Jose Manuel

2013-01-01

371

Temperature characteristics of winter roost-sites for birds and mammals: tree cavities and anthropogenic alternatives  

NASA Astrophysics Data System (ADS)

The microclimate of potential roost-sites is likely to be a crucial determinant in the optimal roost-site selection of endotherms, in particular during the winter season of temperate zones. Available roost-sites for birds and mammals in European high trunk orchards are mainly tree cavities, wood stacks and artificial nest boxes. However, little is known about the microclimatic patterns inside cavities and thermal advantages of using these winter roost-sites. Here, we simultaneously investigate the thermal patterns of winter roost-sites in relation to winter ambient temperature and their insulation capacity. While tree cavities and wood stacks strongly buffered the daily cycle of temperature changes, nest boxes showed low buffering capacity. The buffering effect of tree cavities was stronger at extreme ambient temperatures compared to temperatures around zero. Heat sources inside roosts amplified ? T (i.e., the difference between inside and outside temperatures), particularly in the closed roosts of nest boxes and tree cavities, and less in the open wood stacks with stronger circulation of air. Positive ? T due to the installation of a heat source increased in cold ambient temperatures. These results suggest that orchard habitats in winter show a spatiotemporal mosaic of sites providing different thermal benefits varying over time and in relation to ambient temperatures. At cold temperatures tree cavities provide significantly higher thermal benefits than nest boxes or wood stacks. Thus, in winter ecology of hole-using endotherms, the availability of tree cavities may be an important characteristic of winter habitat quality.

Grüebler, Martin U.; Widmer, Silv; Korner-Nievergelt, Fränzi; Naef-Daenzer, Beat

2014-07-01

372

Case studies of frontal passages in a mountain valley with direct access to the bavarian pre-Alpine region results from the German Front Experiment 1987  

Microsoft Academic Search

Summary The orographic impact on cold fronts is investigated in the Loisach River Valley area by means of two events obtained during the German Front Experiment 1987. The discussion is focussed on the frontal passages in the Garmisch area traced from continuous recordings of three meteorological\\/ air-chemical stations at different heights, viz: valley floor (735m), wank peak station (1780m) and

H. Müller; R. Sladkovic

1990-01-01

373

Ocean properties, ice-ocean interactions, and calving front morphology at two major west Greenland glaciers  

NASA Astrophysics Data System (ADS)

Warm sub-polar mode water (SPMW) has been identified as a primary driver of mass loss of marine terminating glaciers draining the Greenland Ice Sheet (GrIS) yet, the specific mechanisms by which SPMW interacts with these tidewater termini remain uncertain. We present oceanographic data from Rink Glacier (RG) and Store Glacier (SG) fjords, two major marine outlets draining the western sector of the GrIS into Baffin Bay over the contrasting melt-seasons of 2009 and 2010. Submarine melting occurs wherever ice is in direct contact with warmer water and the consistent presence of 2.8 °C SPMW adjacent to both ice fronts below 400 m throughout all surveys indicates that melting is maintained by a combination of molecular diffusion and large scale, weak convection, diffusional (hereafter called ubiquitous) melting. At shallower depths (50-200 m), cold, brine-enriched water (BEW) formed over winter appears to persist into the summer thereby buffering this melt by thermal insulation. Our surveys reveal four main modes of glacier-ocean interaction, governed by water depth and the rate of glacier runoff water (GRW) injected into the fjord. Deeper than 200 m, submarine melt is the only process observed, regardless of the intensity of GRW or the depth of injection. However, between the surface and 200 m depth, three further distinct modes are observed governed by the GRW discharge. When GRW is weak (?1000 m3 s-1), upward motion of the water adjacent to the glacier front is subdued, weak forced or free convection plus diffusional submarine melting dominates at depth, and seaward outflow of melt water occurs from the glacier toe to the base of the insulating BEW. During medium intensity GRW (?1500 m3 s-1), mixing with SPMW yields deep mixed runoff water (DMRW), which rises as a buoyant plume and intensifies local submarine melting (enhanced buoyancy-driven melting). In this case, DMRW typically attains hydrostatic equilibrium and flows seaward at an intermediate depth of ?50-150 m, taking the BEW with it. Strong GRW (? 2000 m3 s-1) yields vigorous, buoyant DMRW, which has sufficient vertical momentum to break the sea surface before sinking and flowing seaward, thereby leaving much of the BEW largely intact. Whilst these modes of glacier-ocean interaction significantly affect the ice-ocean interaction in the upper water column (0-200 m), below 200 m both RG and SG are dominated by the weak forced convection/diffusional (herein termed ubiquitous) melting due to the presence of SPMW.

Chauché, N.; Hubbard, A.; Gascard, J.-C.; Box, J. E.; Bates, R.; Koppes, M.; Sole, A.; Patton, H.

2013-11-01

374

Development of a Model System to Identify Differences in Spring and Winter Oat  

PubMed Central

Our long-term goal is to develop a Swedish winter oat (Avena sativa). To identify molecular differences that correlate with winter hardiness, a winter oat model comprising of both non-hardy spring lines and winter hardy lines is needed. To achieve this, we selected 294 oat breeding lines, originating from various Russian, German, and American winter oat breeding programs and tested them in the field in south- and western Sweden. By assaying for winter survival and agricultural properties during four consecutive seasons, we identified 14 breeding lines of different origins that not only survived the winter but also were agronomically better than the rest. Laboratory tests including electrolytic leakage, controlled crown freezing assay, expression analysis of the AsVrn1 gene and monitoring of flowering time suggested that the American lines had the highest freezing tolerance, although the German lines performed better in the field. Finally, six lines constituting the two most freezing tolerant lines, two intermediate lines and two spring cultivars were chosen to build a winter oat model system. Metabolic profiling of non-acclimated and cold acclimated leaf tissue samples isolated from the six selected lines revealed differential expression patterns of 245 metabolites including several sugars, amino acids, organic acids and 181 hitherto unknown metabolites. The expression patterns of 107 metabolites showed significant interactions with either a cultivar or a time-point. Further identification, characterisation and validation of these metabolites will lead to an increased understanding of the cold acclimation process in oats. Furthermore, by using the winter oat model system, differential sequencing of crown mRNA populations would lead to identification of various biomarkers to facilitate winter oat breeding. PMID:22253782

Chawade, Aakash; Lindén, Pernilla; Bräutigam, Marcus; Jonsson, Rickard; Jonsson, Anders; Moritz, Thomas; Olsson, Olof

2012-01-01

375

Deadly Cold: Health Hazards Due to Cold Weather. An Information Paper by the Subcommittee on Health and Long-Term Care of the Select Committee on Aging. House of Representatives, Ninety-Eighth Congress, Second Session (February 1984).  

ERIC Educational Resources Information Center

This paper, on the health hazards of cold weather for elderly persons, presents information from various sources on the death rates in winter throughout the United States. After reviewing the scope of the problem, specific health hazards associated with cold weather are discussed, i.e., hypothermia, fires, carbon monoxide poisoning, and influenza…

Congress of the U.S., Washington, DC. House Select Committee on Aging.

376

Intraseasonal Cold Air Outbreak over East Asia and the preceding atmospheric condition over the Barents-Kara Sea  

NASA Astrophysics Data System (ADS)

Frequent occurrence of cold air outbreak is a dominant feature of the East Asian winter monsoon. A contributing factor for the this cold air outbreak is the role of stationary Rossby waves over the Eurasian continent which intensifies the surface Siberian High and the accompanying cold air outflow. Reduced sea ice and increase in turbulence heat flux is hypothesized as a source of such stationary waves (Honda et al. 2009). In particular, the winter of 2009/2010 saw a strong correlation of high pressure anomaly over the Barents/Kara sea and the following cold air buildup over the Eurasian continent and its advection towards East Asia (Hori et al. 2011). The lag correlation of surface temperature over Japan and the 850hPa geopotential height shows a cyclonic anomaly appearing over the Barents/Kara sea which creates a cold air advection over the Eurasian continent. The pressure anomaly subsequently shifted westward to mature into a blocking high which created a wave- train pattern downstream advecting the cold air buildup eastward toward East Asia and Japan (Fig1). We further examine this mechanism for other years including the 2005/2006, 2010/2011 winter and other winters with extreme cold air outbreaks. Overall, the existence of an anticyclonic anomaly over the Barents/Kara sea correlated well with the seasonal dominance of cold air over the Eurasian continent thereby creating a contrast of a warm Arctic and cold Eurasian continent.In the intraseasonal timescale, the existence of this anticyclone corresponds to a persisting atmospheric blocking in the high latitudes. In the presentation, we address the underlying chain of events leading up to a strong cold air outbreak over East Asia from an atmosphere - sea ice - land surafce interaction point of view for paritular cold winter years.

Hori, M. E.; Inoue, J.

2011-12-01

377

Multiple thermal fronts near the Patagonian shelf break  

NASA Astrophysics Data System (ADS)

Eighteen year (1985-2002) sea surface temperature (SST) data are used to study the intraseasonal variability of the Patagonian shelf break front (SBF) in the SW South Atlantic Ocean between 39° and 44°S. The cross-shelf break SST gradients reveal distinct, previously undocumented thermal fronts located both, offshore and inshore of the SBF. Throughout the year the main SBF, identified as a band of negative SST gradient maxima (relatively strong offshore temperature decrease), forms a persistent feature located closed to the 200 m isobath, while two distinct negative gradient maxima are located inshore and offshore of this location. Daily SST images reveal the presence of three branches of cold waters whose edges delineate the above mentioned fronts. The two offshore branches closely follow lines of constant potential vorticity (f/h) and appear to be associated with the Malvinas Current, while a third branch, located further onshore, is not steered by the bottom topography. South of 40°S the onshore branch forms a quasi permanent front parallel to the SBF.

Franco, Bárbara C.; Piola, Alberto R.; Rivas, Andrés L.; Baldoni, Ana; Pisoni, Juan P.

2008-01-01

378

The Front-End System For MARE In Milano  

NASA Astrophysics Data System (ADS)

The first phase of MARE consists of 72 ?-bolometers composed each of a crystal of AgReO4 readout by Si thermistors. The spread in the thermistor characteristics and bolometer thermal coupling leads to different energy conversion gains and optimum operating points of the detectors. Detector biasing levels and voltage gains are completely remote-adjustable by the front end system developed, the subject of this paper, achieving the same signal range at the input of the DAQ system. The front end consists of a cold buffer stage, a second pseudo differential stage followed by a gain stage, an antialiasing filter, and a battery powered detector biasing set up. The DAQ system can be used to set all necessary parameters of the electronics remotely, by writing to a ?-controller located on each board. Fiber optics are used for the serial communication between the DAQ and the front end. To suppress interference noise during normal operation, the clocked devices of the front end are maintained in sleep-mode, except during the set-up phase of the experiment. An automatic DC detector characterization procedure is used to establish the optimum operating point of every detector of the array. A very low noise level has been achieved: about 3nV/?Hz at 1 Hz and 1 nV/?Hz for the white component, high frequencies.

Arnaboldi, Claudio; Pessina, Gianluigi

2009-12-01

379

Identification of Solid-Stem Winter Wheat Lines with Enhanced Winter Hardiness Phil Bruckner, Winter Wheat Breeder  

E-print Network

Identification of Solid-Stem Winter Wheat Lines with Enhanced Winter Hardiness Phil Bruckner, Winter Wheat Breeder Project Description Montana winter wheat producers planted 2.45 million acres in 2009, 60% of which was grown in the North Central District. The leading winter wheat cultivar over

Maxwell, Bruce D.

380

The contribution of Alaskan, Siberian, and Canadian coastal polynyas to the cold halocline layer of the Arctic Ocean  

Microsoft Academic Search

Numerous Arctic Ocean circulation and geochemical studies suggest that ice growth in polynyas over the Alaskan, Siberian, and Canadian continental shelves is a source of cold, saline water which contributes to the maintenance of the Arctic Ocean halocline. The purpose of this study is to estimate for the 1978-1987 winters the contributions of Arctic coastal polynyas to the cold halocline

Donald J. Cavalieri; Seelye Martin

1994-01-01

381

winter storm activity  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. It provides an interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Form groups of three. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What usually happens when there is a large difference between the temperatures? 4. What happens when there ...

Miss Prested

2010-05-26

382

Big6 Winter Production  

NSDL National Science Digital Library

Goals: a. Students will be able to identify the four seasons. b. Students will be able to identify three animals (bear, goose, moose) and know their lifestyle patterns in congruence with the four seasons, especially Winter months. c. Students will develop an understanding of their environment. 2nd Grade Standard III: Students will develop an understanding of their environment Objective 2: Observe and describe weather Goal C: Describe how weather affects people and weather Lesson Objectives: a. Identify the seasons and represent each with pictures and songs. b. Observe and describe typical weather for each of ...

Mrs. Cook

2010-11-05

383

Ensemble Applications in Winter  

NSDL National Science Digital Library

This lesson provides an introduction to ensemble forecast systems using an operational case study of the Blizzard of 2013 in Southern Ontario. The module uses models available to forecasters in the Meteorological Service of Canada, including Canadian and U.S. global and regional ensembles. After briefly discussing the rationale for ensemble forecasting, the module presents small lessons on probabilistic ensemble products useful in winter weather forecasting, immediately followed by forecast applications to a southern Ontario case. The learner makes forecasts for the Ontario Storm Prediction Center area and, in the short range, for the Toronto metropolitan area. An additional section applies a probabilistic aviation product to forecasts for Toronto Pearson International Airport.

COMET

2014-04-22

384

Change in abundance of pacific brant wintering in alaska: evidence of a climate warming effect?  

USGS Publications Warehouse

Winter distribution of Pacific Flyway brant (Branta bernicla nigricans) has shifted northward from lowtemperate areas to sub-Arctic areas over the last 42 years. We assessed the winter abundance and distribution of brant in Alaska to evaluate whether climate warming may be contributing to positive trends in the most northern of the wintering populations. Mean surface air temperatures during winter at the end of the Alaska Peninsula increased about 1??C between 1963 and 2004, resulting in a 23% reduction in freezing degree days and a 34% decline in the number of days when ice cover prevents birds from accessing food resources. Trends in the wintering population fluctuated with states of the Pacific Decadal Oscillation, increasing during positive (warm) phases and decreasing during negative (cold) phases, and this correlation provides support for the hypothesis that growth in the wintering population of brant in Alaska is linked to climate warming. The size of the wintering population was negatively correlated with the number of days of strong northwesterly winds in November, which suggests that the occurrence of tailwinds favorable for migration before the onset of winter was a key factor in whether brant migrated from Alaska or remained there during winter. Winter distribution of brant on the Alaska Peninsula was highly variable and influenced by ice cover, particularly at the heavily used Izembek Lagoon. Observations of previously marked brant indicated that the Alaska wintering population was composed primarily of birds originating from Arctic breeding colonies that appear to be growing. Numbers of brant in Alaska during winter will likely increase as temperatures rise and ice cover decreases at high latitudes in response to climate warming. ?? The Arctic Institute of North America.

Ward, D.H.; Dau, C.P.; Lee, T.; Sedinger, J.S.; Anderson, B.A.; Hines, J.E.

2009-01-01

385

of Washington WINTER QUARTER 1994  

E-print Network

University of Washington Bulletin WINTER QUARTER 1994 Student Telephone Assisted Registration..............................................................................................6 On-leave - GraduateStudents...............................................................10 Address ChangeTelephone Service....:..................................................7 Overload

Kaminsky, Werner

386

Record-breaking Ozone Loss during Arctic Winter 2010/2011: Comparison with Arctic Winter 1996/1997  

NASA Astrophysics Data System (ADS)

Polar processing and chemical ozone loss is analysed during the Arctic winter/spring 2010/2011. The analyses with temperatures and potential vorticity (PV) data show a prolonged vortex from early December through mid-April. The PV maps illustrate strong vortex persistence in the lower stratosphere between 450 and 675 K, showing similar evolution with time. The minimum temperatures extracted from ECMWF data at 40-90°N show values below 195 K for a record period of first week of December through second week of April, indicating the longest period of colder temperatures for 17 years. At 10 hPa, there was a warming of about 10 K at 60°N and 40 K at 90°N around mid-January. The heat flux also showed high values in line with the increase in temperatures, of about 425 m K/s at 60°N at the same pressure level. However, the westerlies were strong (e.g. 35-45 m/s at 60°N) enough to keep the vortex intact until mid-April. Because of the cold temperatures in late winter and early spring, large areas of Polar Stratospheric Clouds (PSC) were found in the 400-600 K isentropic level range. Though the maximum values of PSCs area are smaller compared to other cold winters such as 2005, the extended period of presence of PSCs during this winter was exceptional, especially in late February-mid-March, in agreement with the cold temperatures during the period. Ozone loss analyses with high resolution Mimosa-Chim chemical transport model simulations show that the loss started by early January, and was about 0.5 ppmv in late January. The loss progressed slowly to 1 ppmv by the end of February, and then intensified by early March. The ozone depletion estimated by the passive method finds a maximum value of about 2-2.3 ppmv by the end of March-early April in the 450-550K range inside the vortex, which coincides with the areas of PSCs and high chlorine activation. This is the largest loss ever estimated with this model for any Arctic winter. It is consistent with the unprecedented chlorine activation that occurred in the winter, as the modeled ClO values show about 1.7 ppbv in early January and about 1 ppbv in March at 450-550K. This is longest period of chlorine activation noted among the Arctic winters. The ozone partial column loss reaches about 115-150 DU in the range 350 - 550 K. These model results for ozone, ozone loss and ClO are in good agreement with those found from Aura Microwave Limb Sounder observations. Since the winter 1996/1997 was also very cold in March - April, a comparison between both winters 2011 and 1997 will be presented, based on temperature, PV, Heat flux data and ozone loss estimations. Similarities and differences in the polar processing and ozone loss during both winters will be discussed using various measurements and model simulations. Copyright 2011. All rights reserved.

Godin Beekmann, S.; Kuttipurath, J.; Lefèvre, F.; Santee, M. L.; Froidevaux, L.

2011-12-01

387

Cold fusion, Alchemist's dream  

SciTech Connect

In this report the following topics relating to cold fusion are discussed: muon catalysed cold fusion; piezonuclear fusion; sundry explanations pertaining to cold fusion; cosmic ray muon catalysed cold fusion; vibrational mechanisms in excited states of D{sub 2} molecules; barrier penetration probabilities within the hydrogenated metal lattice/piezonuclear fusion; branching ratios of D{sub 2} fusion at low energies; fusion of deuterons into {sup 4}He; secondary D+T fusion within the hydrogenated metal lattice; {sup 3}He to {sup 4}He ratio within the metal lattice; shock induced fusion; and anomalously high isotopic ratios of {sup 3}He/{sup 4}He.

Clayton, E.D.

1989-09-01

388

[The aerobic bacterial intestinal flora of various wintering geese species].  

PubMed

The aerobic fecal flora of wintering Brent Goos (Branta bernicla), Barnacle Goose (Branta leucopsis), Greylag Goose (Anser anser), White-fronted Goose (Anser albifrons), Pink-footed Goose (Anser brachyrhynchus), and Bean Goose (Anser fabalis) was studied. There were no specific differences between the various geese. Bacterial counts were in the range of 10(5)-10(7) CPU per gram of feces. Neither pathogenic bacteria nor rotavirus could be detected in the fecal samples of the wintering geese, so that a contamination of the environment with those pathogenic organisms could be excluded. The majority of the isolated bacteria belonged to the genera Bacillus and Pseudomonas; enterobacteria and streptococci were less common. The observations are discussed regarding their epidemiological and ecological significance. PMID:7136353

Holländer, R

1982-07-01

389

Sarcomere length determination using front-face fluorescence polarization.  

PubMed

Tryptophan is the major intrinsic fluorophore in muscle and is a constituent of proteins that have two preferential alignments both parallel and perpendicular to muscle fibre direction. A simple theoretical model and an experimental method based on front-face fluorescence polarization technique for tryptophan fluorescence anisotropy measurements were used for the estimation of post-rigor sarcomere length in beef in the range 1.6-3.4?m. Fluorescence anisotropy and structure-related model variables displayed changes in cold-shortened samples compared with normal and stretched ones. The anisotropy of contracted samples was lowered by misalignment of fibres in the sample. This method can therefore be used for in-line detection of cold shortening which has meat toughness as a consequence. PMID:22063601

Luc, C; Clerjon, S; Peyrin, F; Lepetit, J; Culioli, J

2008-11-01

390

Trends of cold and heat waves in Serbia  

NASA Astrophysics Data System (ADS)

The series of the daily minimum and maximum temperatures at fifteen stations in Serbia were used to calculate the cold and warm spell duration indicators, from which the duration and severity of the cold and heat waves were estimated. The trend analysis for all seasons was presented using the data from 1949 to 2012. The most important result of this study is the significant decreasing trends in the frequency of cold waves and increasing trends of heat waves in Serbia. An analysis of the daily minimum temperatures almost at all meteorological stations revealed that the longest and most severe cold waves were observed in winter of 1956, spring of 1987, summer of 1962 and 1996, and during the autumn 1983 and 1988. The longest and most severe heat waves, based on the analysis of the daily maximum temperatures, were recorded in winter of 2007, spring of 2003, summer of 2012, and after 1989 during the autumn. The longest heat waves observed in 2012 did not reach the severity of the heat waves in 2007 at ten of fifteen stations. The obtained results indicated that the warming in Serbia was more related to increase in frequency of heat waves than to reduction in cold waves.

Unkaševi?, Miroslava; Toši?, Ivana

2014-05-01

391

Preventing cold-related morbidity and mortality in a changing climate  

PubMed Central

Winter weather patterns are anticipated to become more variable with increasing average global temperatures. Research shows that excess morbidity and mortality occurs during cold weather periods. We critically reviewed evidence relating temperature variability, health outcomes, and adaptation strategies to cold weather. Health outcomes included cardiovascular-, respiratory-, cerebrovascular-, and all-cause morbidity and mortality. Individual and contextual risk factors were assessed to highlight associations between individual- and neighborhood- level characteristics that contribute to a person’s vulnerability to variability in cold weather events. Epidemiologic studies indicate that the populations most vulnerable to variations in cold winter weather are the elderly, rural and, generally, populations living in moderate winter climates. Fortunately, cold-related morbidity and mortality are preventable and strategies exist for protecting populations from these adverse health outcomes. We present a range of adaptation strategies that can be implemented at the individual, building, and neighborhood level to protect vulnerable populations from cold-related morbidity and mortality. The existing research justifies the need for increased outreach to individuals and communities for education on protective adaptations in cold weather. We propose that future climate change adaptation research couple building energy and thermal comfort models with epidemiological data to evaluate and quantify the impacts of adaptation strategies. PMID:21592693

Conlon, Kathryn C; Rajkovich, Nicholas B; White-Newsome, Jalonne L; Larsen, Larissa; Neill, Marie S O

2011-01-01

392

Overwintering Strategy and Mechanisms of Cold Tolerance in the Codling Moth (Cydia pomonella)  

PubMed Central

Background The codling moth (Cydia pomonella) is a major insect pest of apples worldwide. Fully grown last instar larvae overwinter in diapause state. Their overwintering strategies and physiological principles of cold tolerance have been insufficiently studied. No elaborate analysis of overwintering physiology is available for European populations. Principal Findings We observed that codling moth larvae of a Central European population prefer to overwinter in the microhabitat of litter layer near the base of trees. Reliance on extensive supercooling, or freeze-avoidance, appears as their major strategy for survival of the winter cold. The supercooling point decreases from approximately ?15.3°C during summer to ?26.3°C during winter. Seasonal extension of supercooling capacity is assisted by partial dehydration, increasing osmolality of body fluids, and the accumulation of a complex mixture of winter specific metabolites. Glycogen and glutamine reserves are depleted, while fructose, alanine and some other sugars, polyols and free amino acids are accumulated during winter. The concentrations of trehalose and proline remain high and relatively constant throughout the season, and may contribute to the stabilization of proteins and membranes at subzero temperatures. In addition to supercooling, overwintering larvae acquire considerable capacity to survive at subzero temperatures, down to ?15°C, even in partially frozen state. Conclusion Our detailed laboratory analysis of cold tolerance, and whole-winter survival assays in semi-natural conditions, suggest that the average winter cold does not represent a major threat for codling moth populations. More than 83% of larvae survived over winter in the field and pupated in spring irrespective of the overwintering microhabitat (cold-exposed tree trunk or temperature-buffered litter layer). PMID:23613923

Rozsypal, Jan; Koštál, Vladimír; Zahradní?ková, Helena; Šimek, Petr

2013-01-01

393

Tracking Water Vapor in the Winter High Arctic using the Microwave Humidity Sounder  

Microsoft Academic Search

The cold and dry conditions during the darkness of the winter High Arctic have been a challenge for the retrieval of tropospheric water vapor amounts from satellites. Water vapor remains the most important greenhouse gas even in these dry conditions and so its variability has a direct bearing on the radiative forcing at the surface. The presence of the surface-based

T. J. Duck; G. B. Lesins; J. R. Drummond

2010-01-01

394

Simultaneous Genetic Analysis of Winterhardiness Traits and Development of Winter Malting Barley Varieties  

Technology Transfer Automated Retrieval System (TEKTRAN)

The practical goal of this project is to develop winter malting barley varieties with superior cold tolerance. The basic goal is to advance our understanding of the genetics of low temperature tolerance and vernalization sensitivity. By addressing the question, “Is vernalization sensitivity required...

395

Winter Hydrological and Erosion Processes in the U. S. Palouse Region: Field Experimentation and WEPP Simulation  

Technology Transfer Automated Retrieval System (TEKTRAN)

Soil erosion by water is detrimental to soil fertility and crop yield as well as the environment. For cold areas, knowledge of winter hydrological processes is critical to determining alternative land-use and management practices for reducing soil loss and protecting land and water resources. Adequa...

396

OVER WINTER STABILITY AND HYDROLOGY OF MACROPORES IN THE NORTHERN US CORN BELT  

Technology Transfer Automated Retrieval System (TEKTRAN)

Macropores created by biological or physical processes can profoundly influence water movement through the soil. In cold regions, macropore stability can be influenced by natural processes such as wetting/drying and freezing/thawing. Little is known, however, concerning the over winter stability of ...

397

Relationship between frost tolerance and sugar concentration of various bryophytes in summer and winter  

Microsoft Academic Search

Frost resistance, measured via the photosynthetic capacity after freeze-thaw treatment, and concentrations of sucrose, glucose and fructose of thalli of seven species of Bryidae and one species of Marchantiidae were determined from January to March and June to September, respectively. A distinct increase in cold tolerance from summer to winter was found in Polytrichum formosum Hedw., Atrichum undulatum (Hedw.) P.

Dorothea Riitten; Kurt A. Santarius

1992-01-01

398

EVIDENCE OF A MAJOR GENETIC FACTOR CONDITIONING FREEZING SENSITIVITY IN WINTER WHEAT  

Technology Transfer Automated Retrieval System (TEKTRAN)

Freezing tolerance was measured in cold-acclimated F2 – derived F4 lines of winter wheat (Triticum aestivum L.) crosses 'Eltan' X Oregon Feed Wheat #5' (ORFW) and 'Tiber' X ORFW. ORFW had essentially no freezing tolerance, while 'Eltan' and 'Tiber' had about 50% survival, as measured in this study....

399

A NEW MODEL TO ESTIMATE DAILY ENERGY EXPENDITURE FOR WINTERING WATERFOWL  

EPA Science Inventory

Activity budgets of wintering waterfowl have been widely used to assess habitat quality. However, when factors such as prey abundance or protection from exposure to cold or wind determine quality, measures of daily energy expenditure (DEE) may be more appropriate for this purpos...

400

Red spruce decline---Winter injury and air pollutants  

SciTech Connect

There has been a widespread decline in growth of red spruce (Picea rubens Sarg.) since 1960 in the eastern United States. There is evidence that this decline is at least partly attributable to age- and density-related growth patterns, particularly at lower elevations. Mortality has been severe at high elevation sites where similar episodes have occasionally occurred in the last 100 years. At these sites, periods of low growth preceding 1960 were related to periods with warm late summers and cold early winters. Since 1960, this relationship no longer holds, although there is an association with unusual deviations from mean temperatures. There are field reports that one of the main causes of reduced growth and mortality is apical dieback induced by severe winter conditions. Preliminary observations suggest that high elevation red spruce may not be sufficiently hardened to tolerate low autumn temperatures. However, appearance of injury in the spring, association of injury with wind exposure and correlation of provenance susceptibility with cuticular transpiration rates, including the importance of desiccation injury. Sensitivity to both types of winter injury may be increased by air pollutants (particularly ozone and less probably, acid mist or excess nitrogen deposition). Nutrient deficiency (particularly magnesium and to a lesser extent potassium) may also increase cold sensitivity. The nature and extent of these interactions are being actively researched for red spruce. 48 refs.

Roberts, T.M. (Central Electricity Research Labs., Leatherhead (UK))

1989-10-01

401

Pocahontas and The Winter's Tale  

Microsoft Academic Search

This essay argues what is on the face of it a ludicrous claim: that Shakespeare's play The Winter's Tale can profitably be read in the light of the story of the Algonquian princess Pocahontas. The reason that this seems ludicrous is quite simply that The Winter's Tale was almost certainly written before Shakespeare can have heard of Pocahontas, and in

Lisa Hopkins

2005-01-01

402

Cold Air Damming  

NSDL National Science Digital Library

Cold Air Damming is part of the Mesoscale Meteorology Primer series. This module first presents a Navy forecast scenario prior to the development of a major cold air damming (CAD) event along the east slopes of the Appalachian Mountains. Then, from a conceptual standpoint, the classic CAD scenario is described in detail, both from an observational and modeling standpoint.

COMET

2001-06-18

403

Front tracking for gas dynamics  

NASA Astrophysics Data System (ADS)

Front tracking represents an adaptive computational method for modeling fluid flow. Adaptive methods provide increased resolution by making use of special computational degrees of freedom which (a) are placed (in space and time) where they are most needed, and (b) fit the nature of the solution as closely as possible. 'Tracking' is distinguished by the choice of a lower dimensional adaptive grid, called the front or the interface, as its special computational degree of freedom. For flow problems in two space dimensions, tracking employs a moving one-dimensional grid, i.e., a system of curves, in addition to a two-dimensional grid. The use of tracking appears attractive for problems containing discontinuities and other singularities concentrated on surfaces. The work reported in this paper has the objective to implement a general purpose computational package based on front tracking ideas. Problems in compressible fluid dynamics are considered.

Chern, I.-L.; Glimm, J.; McBryan, O.; Plohr, B.; Yaniv, S.

1986-01-01

404

Analytical models of dipolarization fronts  

NASA Astrophysics Data System (ADS)

Dipolarization fronts (DFs) are mesoscale structures generated during the transient magnetic reconnection in the Earth's magnetotail. Spacecraft often observe these structures propagating toward the Earth with velocities 300-100 km/s. Modern multispacecraft observations allow reconstruction of 3D configuration of electromagnetic fields of DF: front is strongly curved in the XY plane and spatially localized along the Z axis (in GSM coordinate system). DFs play important role in plasma heating and charged particle acceleration. Thus, the simplified analytical models of 2D and 3D configuration of DF are necessary to model charge particle interaction with fronts. In the present report we propose 3D analytical model of DF. For several given distributions of B _{z} magnetic field component we have found analytical expressions for magnetic fields B _{x}, B _{y} and electric fields E _{x}, E _{y}. We also discuss distribution of electric field, which is due to the polarization of plasma in the vicinity of DF.

Vasko, Ivan; Artemyev, Anton

405

Sex-specific winter distribution in a sexually dimorphic shorebird is explained by resource partitioning  

PubMed Central

Sexual size dimorphism (SSD) implies correlated differences in energetic requirements and feeding opportunities, such that sexes will face different trade-offs in habitat selection. In seasonal migrants, this could result in a differential spatial distribution across the wintering range. To identify the ecological causes of sexual spatial segregation, we studied a sexually dimorphic shorebird, the bar-tailed godwit Limosa lapponica, in which females have a larger body and a longer bill than males. With respect to the trade-offs that these migratory shorebirds experience in their choice of wintering area, northern and colder wintering sites have the benefit of being closer to the Arctic breeding grounds. According to Bergmann's rule, the larger females should incur lower energetic costs per unit of body mass over males, helping them to winter in the cold. However, as the sexes have rather different bill lengths, differences in sex-specific wintering sites could also be due to the vertical distribution of their buried prey, that is, resource partitioning. Here, in a comparison between six main intertidal wintering areas across the entire winter range of the lapponica subspecies in northwest Europe, we show that the percentage of females between sites was not correlated with the cost of wintering, but was positively correlated with the biomass in the bottom layer and negatively with the biomass in the top layer. We conclude that resource partitioning, rather than relative expenditure advantages, best explains the differential spatial distribution of male and female bar-tailed godwits across northwest Europe. PMID:25505527

Duijns, Sjoerd; van Gils, Jan A; Spaans, Bernard; ten Horn, Job; Brugge, Maarten; Piersma, Theunis

2014-01-01

406

Winter Adapted Games First-Years Wanted!!!  

E-print Network

Winter Adapted Games aka WAG First-Years Wanted!!! Be a part of WAG ... one of the best events. The Winter Adapted Games (WAG) is an all-day winter event organized by students in the School of Kinesiology

Abolmaesumi, Purang

407

Anterior knee pain and cold knees: a possible association in women.  

PubMed

Abnormal reactions to environmental cold have been observed in some patients with Anterior Knee Pain (AKP). The aims of this study were to investigate whether palpation of the knee could classify patients into those with and those without cold knees; whether this classification could be objectively validated using thermal imaging; whether the cold and not cold knee groups varied in response to a cold stress test and in patient-reported measures. Fifty eight patients were recruited; palpation classified them into cold and not cold groups. Twenty-one (36%) patients were classified as having a cold knee by palpation: fourteen (36%) females and seven males (37%). Preliminary analysis suggested gender might be an effect modifier and the number of men was small, therefore the analysis focussed on females. Women with cold knees had a significantly smaller patellar skin fold, lower levels of activity and worse scores on the MFIQ, there also appeared to be an association with a traumatic onset. Women with cold knees were more likely to report cold weather affected their knees and they preferred a hot water bottle compared to an ice-pack on their knee; there was also a trend towards having to wear extra tights/long johns in the winter. This study has helped to define a clinical profile for a group of females with AKP and cold knees. This group appears to demonstrate a mild form of Reflex Sympathetic Dystrophy. PMID:19884010

Selfe, James; Sutton, Chris; Hardaker, Natalie J; Greenhalgh, Sue; Karki, Anne; Dey, Paola

2010-10-01

408

Lagrangian fronts in the ocean  

NASA Astrophysics Data System (ADS)

We introduce the concept of Lagrangian fronts (LFs) in the ocean and describe their importance for analyzing water mixing and transport and the specific features and differences from hydrological fronts. A method of calculating LFs in a given velocity field is proposed. Based on altimeter velocity fields from AVISO data in the northwestern Pacific, we calculate the Lagrangian synoptic maps and identify LFs of different spatial and temporal scales. Using statistical analysis of saury catches in different years according to the Goskomrybolovstvo (State Fisheries Committee of the Russian Federation), we show that LFs can serve as good indicators of places that are favorable for fishing.

Prants, S. V.; Budyansky, M. V.; Uleysky, M. Yu.

2014-05-01

409

Front tracking for gas dynamics  

NASA Astrophysics Data System (ADS)

Front tracking is an adaptive computational method in which a lower dimensional moving grid is fitted to and follows the dynamical evolution of distinguished waves in a fluid flow. The method takes advantage of known analytic solutions, derived from the Rankine-Hugoniot relations, for idealized discontinuities. The method is applied to the Euler equations describing compressible gas dynamics. The main thrust is validation of the front tracking method: results are presented on a series of test problems for which comparison answers can be obtained by independent methods.

Chern, I. L.; Glimm, J.; McBryan, O.; Plohr, B.; Yaniv, S.

1984-05-01

410

Cold adaptation in the phytopathogenic fungi causing snow molds  

Microsoft Academic Search

Snow molds are psychrophilic or psychrotrophic fungal pathogens of forage crops, winter cereals, and conifer seedlings. These\\u000a fungi can grow and attack dormant plants at low temperatures under snow cover. In this review, we describe the biodiversity\\u000a and physiological and biochemical characteristics of snow molds that belong to various taxa. Cold tolerance is one of the\\u000a important factors related to

Tamotsu Hoshino; Nan Xiao; Oleg B. Tkachenko

2009-01-01

411

Individual inconsistencies in basal and summit metabolic rate highlight flexibility of metabolic performance in a wintering passerine.  

PubMed

Resident passerines inhabiting high latitude environments are faced with strong seasonal changes in thermal conditions and energy availability. Summit metabolic rate (maximal metabolic rate elicited by shivering during cold exposure: Msum ) and basal metabolic rate (BMR) vary in parallel among seasons and increase in winter due to cold acclimatization, and these adjustments are thought to be critical for survival. Wintering individuals expressing consistently higher Msum and BMR could therefore be seen as better performers with higher chances of winter survival than those exhibiting lower metabolic performance. In this study, we calculated repeatability to evaluate temporal consistency of body mass, BMR and Msum within and across three consecutives winters in black-capped chickadees (Poecile atricapillus). We found that body mass was significantly repeatable both within and across winters (R 0.51-0.90). BMR (R 0.29-0.47) was only repeatable within winter while Msum was repeatable both among (R 0.33-0.49) and within winters (R 0.33-0.49) with the magnitude and significance of repeatability in both variables depending on the year and whether they were corrected for body mass or body size. The patterns of repeatability observed among years also differed between the two variables. Our findings suggest that the relative ranking of individuals in winter metabolic performance is affected by local ecological conditions and can change within relatively short periods of time. J. Exp. Zool. 323A: 179-190, 2015. © 2015 Wiley Periodicals, Inc. PMID:25690265

Cortés, Pablo Andrés; Petit, Magali; Lewden, Agnès; Milbergue, Myriam; Vézina, François

2015-03-01

412

Role of the nocturnal coastal-front depth on cloud formation and precipitation in the Mediterranean basin  

NASA Astrophysics Data System (ADS)

Ten nocturnal coastal front events formed in the Mediterranean basin are simulated and analyzed, focusing on the coastal-front depth by using version 3.3 of the WRF-ARW mesoscale model. During the night the inland air cools faster than the air over the Mediterranean Sea. Consequently, this colder air may move offshore, forming a coastal front when interacting with the warmer and moister maritime air mass, which is lifted over the colder air. Then clouds and precipitation may occur. In this mechanism the depth of the cold air mass (H) plays an important role in theformation of clouds and precipitation. Stratiform clouds appear if H is higher than the lifting condensation level of the warm air mass. Moreover, if H is higher than the corresponding level of free convection convective clouds are formed. H is estimated from the mesoscale simulations at an hourly scale, as well as taking the average and maximum values during the whole night. Furthermore, several parameters related to trigger convection, the blockage effect that the cold air mass offers to the prevailing flow, the deceleration induced by cold front on the upstream maritime flow and the location of precipitation with respect to the front are estimated. Additionally, a forecasting cloud-band index is proposed in order to evaluate whether stratiform clouds are formed offshore in the ten simulated nocturnal coastal fronts.

Mazon, Jordi; Pino, David

2015-02-01

413

Winter fuels report  

SciTech Connect

The Winter Fuels Report is intended to provide consise, timely information to the industry, the press, policymakers, consumers, analysts, and State and local governments on the following topics: Distillate fuel oil net production, imports and stocks on a US level and for all Petroleum Administration for Defense Districts (PADD) and product supplied on a US level; Natural gas supply and disposition and underground storage for the US and consumption for all PADD`s as well as selected National average prices; Residential and wholesale pricing data for heating oil and propane for those States participating in the joint Energy Information Administration (EIA)/State Heating Oil and Propane Program; Crude oil and petroleum price comparisons for the US and selected cities; and A 6-10 Day and 30-Day outlook for temperature and precipitation and US total heating degree days by city.

Not Available

1995-02-17

414

Winter Clouds Over Mie  

NASA Technical Reports Server (NTRS)

12 March 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) red wide angle image shows late winter clouds over the 104 km (65 mi) diameter crater, Mie. Cellular clouds occur in the lower martian atmosphere, surrounding Mie Crater. Their cloudtops are at an altitude that is below the crater rim. Higher than the crater rim occurs a series of lee wave clouds, indicating air circulation moving from west/northwest (left) toward the east/southeast (right). Mie Crater is located in Utopia Planitia, not too far from the Viking 2 landing site, near 48.5 N, 220.4 W. Sunlight illuminates this January 2004 scene from the lower left.

2004-01-01

415

A Winter's Tale  

NSDL National Science Digital Library

This resource explores winter weather and frozen precipitation. The page on precipitation points out that snow and rain are both water and explains how the different forms of frozen precipitation (snow, sleet, freezing rain) occur. There is a page on cirrus clouds that explains their characterstics and how they may affect climate by reflecting solar radiation or reducing outgoing infrared energy from Earth. The Jet Stream page explains the characteristics of these high-speed rivers of air, including what causes them and their effect on weather and climate. There is also a feature on the esthetic wonders of frozen water, including halos produced by ice crystals in the air, sparkling of snowflakes, why fresh snow squeaks when stepped on, and why it is silent during a snowfall. A bibliography is also provided.

416

Winter fuels report  

SciTech Connect

The Winter Fuels Report is intended to provide concise, timely information to the industry, the press, policymakers, consumers, analysts, and State and local governments on the following topics: distillate fuel oil net production, imports and stocks on a US level and for all Petroleum Administration for Defense Districts (PADD) and product supplied on a US level; propane net production, imports and stocks on a US level and for PADD`s I, II, and III; natural gas supply and disposition and underground storage for the US and consumption for all PADD`s; as well as selected National average prices; residential and wholesale pricing data for heating oil and propane for those States participating in the joint Energy Information Administration (EIA)/State Heating Oil and Propane Program; crude oil and petroleum price comparisons for the US and selected cities; and a 6-10 Day and 30-Day outlook for temperature and precipitation and US total heating degree-days by city.

Not Available

1995-02-03

417

Changes in hematological profiles during winter field operations  

SciTech Connect

The authors have previously shown that there are changes in hematological profiles during experimental cold acclimation. They now report on hematological changes in 9 military volunteers during a 12 week winter field operation and show results similar to those observed during experimental cold acclimation. Blood was collected before and after completion of winter field operations and analyzed in a paired fashion. Hematocrit (HCT) and erythrocyte counts (RBC) were decreased; mean corpuscular hemoglobin concentration (MCHC) and plasma volume (PV), which was calculated from hemoglobin (Hb) concentration and HCT, were increased. In addition, the reticulocyte count was increased from 1.37 {plus minus} 0.10% to 2.62 {plus minus} 0.24% after completion of field operations. There was a statistically significant inverse correlation between HCT and reticulocyte count, indicating the need for an enhanced rate of red cell production. Hemoglobin concentration, leukocyte count, and mean corpuscular volume were unchanged. The RBC population, to remain at steady state during periods of chronic cold exposure, shows alterations in the number of circulating cells, Hb concentration per cell and possibly cell turnover.

Lopez, A.; Reed, L.; D'Alesandro, M. (Naval Medical Research Inst., Bethesda, MD (United States))

1991-03-11

418

Habitat Suitability Index Models: American Black Duck (Wintering)  

USGS Publications Warehouse

INTRODUCTION The American black duck, commonly known as the black duck, is migratory and has a wide geographic range. American black ducks breed from Cape Hatteras, North Carolina, west to the Mississippi River and north through the eastern Canadian boreal forest (Bellrose 1976). The winter range extends from the Rio Grande River on the Texas coast, northeast to Lake Michigan, east to Nova Scotia, south to Florida, and west to Texas (Wright 1954). American black ducks arrive on their wintering habitats between September and early December and remain there until February to April (Bellrose 1976). Their preferred habitat varies considerably through the wintering range. Habitat use appears related to food availability, freedom from disturbance, weather, and often upon the presence of large bodies of open water. These interrelated elements are essential for meeting the energy demands and other nutritional requirements of black ducks in response to the rigors of cold weather and migration. In the Atlantic Flyway, winter populations of American black ducks concentrate in marine and estuarine wetlands (U.S. Fish and Wildlife Service 1979). They use salt marshes and small tidal bays for feeding and loafing areas. In wintering areas north of Chesapeake Bay, American black ducks frequently feed on tidal flats and rest in emergent wetlands or on ice-free bays, rivers, and coastal reservoirs. In the Chesapeake bay area, migrant and wintering American black ducks occupy a wide variety of habitats (Stewart 1962). They strongly favor brackish bays with extensive adjacent agricultural lands. Estuarine bays, coastal salt marshes, tidal fresh marshes, and adjacent impoundments receive high usage. American black ducks also concentrate in forested wetlands in and adjacent to estuaries in the South Atlantic Flyway, especially in Virginia and North Carolina.

Lewis, James C.; Garrison, Russell L.

1984-01-01

419

Reaction front formation in contaminant plumes  

NASA Astrophysics Data System (ADS)

The formation of successive fronts in contaminated groundwater plumes by subsoil bacterial action is a commonly accepted feature of their propagation, but it is not obviously clear from a mathematical standpoint quite how such fronts are formed or propagate. In this paper we show that these can be explained by combining classical reaction-diffusion theory involving just two reactants (oxidant and reductant), and a secondary reaction in which a reactant on one side of such a front is (re-)formed on the other side of the front via diffusion of its product across the front. We give approximate asymptotic solutions for the reactant profiles, and the propagation rate of the front.

Cribbin, Laura B.; Winstanley, Henry F.; Mitchell, Sarah L.; Fowler, Andrew C.; Sander, Graham C.

2014-12-01

420

Front propagation sustained by additive noise.  

PubMed

The effect of noise in a motionless front between a periodic spatial state and an homogeneous one is studied. Numerical simulations show that noise induces front propagation. From the subcritical Swift-Hohenberg equation with noise, we deduce an adequate equation for the envelope and the core of the front. The equation of the core of the front is characterized by an asymmetrical periodic potential plus additive noise. The conversion of random fluctuations into direct motion of the core of the front is responsible of the propagation. We obtain an analytical expression for the velocity of the front, which is in good agreement with numerical simulations. PMID:16907085

Clerc, M G; Falcón, C; Tirapegui, E

2006-07-01

421

Align the Front End First.  

ERIC Educational Resources Information Center

Discussion of management styles and front-end analysis focuses on a review of Douglas McGregor's theories. Topics include Theories X, Y, and Z; leadership skills; motivational needs of employees; intrinsic and extrinsic rewards; and faulty implementation of instructional systems design processes. (LRW)

Perry, Jim

1995-01-01

422

Front office: asset or liability?  

PubMed

Your front-office staff and your reception area represent the first and last impressions that patients will have of your practice on any given visit. These impressions endure, and in many cases they shape the patient's perception of the doctor. It's critical to your practice's success that these be good impressions. PMID:15379207

Hertz, Kenneth T

2004-08-01

423

Turtle Skeleton - Front Limb (Claw)  

NSDL National Science Digital Library

Turtles use their front limb (flipper) of its skeleton to propel themselves through water. It is webbed and is connected to a ball and socket joint, allowing the turtle to be agile in water. Its sharp claws help the turtle to grab and defend itself.

Ketan Patel (California State University, Fullerton; Student, Biological Sciences)

2007-07-28

424

Turtle Skeleton - Front Limb (Flipper)  

NSDL National Science Digital Library

Turtles use their front limb (flipper) of its skeleton to propel themselves through water. It is webbed and connected to a ball and socket joint, allowing the turtle to be agile in water. Its sharp claws help the turtle to grab and defend itself. The limbs may be tucked inside the turtle's shell when it feels threatened.

Ketan Patel (California State University, Fullerton; Student, Biological Sciences)

2007-06-18

425

PBF Cooling Tower under construction. Cold water basin is five ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

PBF Cooling Tower under construction. Cold water basin is five feet deep. Foundation and basin walls are reinforced concrete. Camera facing west. Pipe openings through wall in front are outlets for return flow of cool water to reactor building. Photographer: John Capek. Date: September 4, 1968. INEEL negative no. 68-3473 - Idaho National Engineering Laboratory, SPERT-I & Power Burst Facility Area, Scoville, Butte County, ID

426

Pacific sea surface temperature and the winter of 2014  

NASA Astrophysics Data System (ADS)

It is shown from historical data and from modeling experiments that a proximate cause of the cold winter in North America in 2013-2014 was the pattern of sea surface temperature (SST) in the Pacific Ocean. Each of the three dominant modes of SST variability in the Pacific is connected to the tropics and has a strong expression in extratropical SST and weather patterns. Beginning in the middle of 2013, the third mode of SST variability was two standard deviations positive and has remained so through January 2015. This pattern is associated with high pressure in the northeast Pacific and low pressure and low surface temperatures over central North America. A large ensemble of model experiments with observed SSTs confirms that SST anomalies contributed to the anomalous winter of 2014.

Hartmann, Dennis L.

2015-03-01

427

On the relationship between winter thunder and the climatic change in China in the past 2200 years  

Microsoft Academic Search

An analysis of winter thunder records in China from 250 B.C. to A.D. 1900 shows that there is a relationship between the pattern\\u000a of winter thunder frequency fluctuation with that of temperature fluctuation. We hypothesized that such a temperature—thunder\\u000a relationship may possibly be due to the strong frontal movement by cold air masses of well-defined low temperature.

Pao-Kuan Wang

1980-01-01

428

On the relationship between winter thunder and the climatic change in China in the past 2200 years  

Microsoft Academic Search

An analysis of winter thunder records in China from 250 B.C. to A.D. 1900 shows that there is a relationship between the pattern of winter thunder frequency fluctuation with that of temperature fluctuation. We hypothesized that such a temperature—thunder relationship may possibly be due to the strong frontal movement by cold air masses of well-defined low temperature.

Pao-Kuan Wang

1980-01-01

429

Nesting habitat of the Tule Greater White-fronted Goose Anser albifrons elgasi  

USGS Publications Warehouse

This paper presents the first information on the availability and use of nesting habitat by the rare Tule Greater White-fronted Goose Anser albifrons elgasi. The breeding range was sampled by marking geese with radio transmitters on wintering and moulting areas, and tracking them to nest sites in Alaska. Nesting habitat was described at the scales of ecoregion, wetland ecosystem (National Wetlands Inventory (NWI) maps), vegetation type within wetland (Alaska Vegetation Classification (AVC) maps based on satellite imagery), and nest site. Tule Greater White-fronted Goose nests were located in boreal forest wetlands in the upper Cook Inlet Basin ecoregion. Nesting Tule Greater White-fronted Geese selected NWT Palustrine Seasonally Flooded wetlands and used NWI Palustrine Saturated wetlands in proportion to availability. Within these wetlands, Tule Greater White-fronted Geese used Needleleaf Forest, Low Shrub and Herbaceous (mostly graminoid) AVC classes for nest sites in proportion to availability Most (93%) Tule Greater White-fronted Geese nested > 75 m from open water ponds or lakes, and many nested in wetlands with little or no open water. Tule Greater White-fronted Geese nest only in a small breeding area near the most human-impacted area of the state, and continued development may limit the use of suitable nesting habitat.

Densmore, R.V.; Ely, C.R.; Bollinger, K.S.; Kratzer, S.; Udevitz, M.S.; Fehringer, D.J.; Rothe, T.C.

2006-01-01

430

Social status does not affect resting metabolic rate in wintering dark-eyed junco (Junco hyemalis).  

PubMed

Studies of wintering birds have demonstrated a correlation between social rank and energy expenditures. It is assumed that dominance is energetically costly because of increased activity, possibly caused by elevated androgen levels. As winter acclimatization leads to an increase in metabolic rate, maintaining dominance status in a cold climate can be a substantial challenge. We measured resting metabolic rates in dominant and subordinate dark-eyed juncos (Junco hyemalis) living in small groups in a controlled winter environment. We found no significant effect of social rank when controlling for body size. It has been shown previously that high testosterone levels during the nonbreeding season can lead to higher body conductance, fat loss, and higher nocturnal body temperature. A hypothesis explaining our result is that for juncos it is preferable to maintain low androgen levels during winter and to maintain social rank using a mechanism other than higher agonistic activity. PMID:10801401

Vézina, F; Thomas, D W

2000-01-01

431

Water masses, ocean fronts, and the structure of Antarctic seabird communities: Putting the eastern Bellingshausen Sea in perspective  

USGS Publications Warehouse

Waters off the western Antarctic Peninsula (i.e., the eastern Bellingshausen Sea) are unusually complex owing to the convergence of several major fronts. Determining the relative influence of fronts on occurrence patterns of top-trophic species in that area, therefore, has been challenging. In one of the few ocean-wide seabird data syntheses, in this case for the Southern Ocean, we analyzed ample, previously collected cruise data, Antarctic-wide, to determine seabird species assemblages and quantitative relationships to fronts as a way to provide context to the long-term Palmer LTER and the winter Southern Ocean GLOBEC studies in the eastern Bellingshausen Sea. Fronts investigated during both winter (April-September) and summer (October-March) were the southern boundary of the Antarctic Circumpolar Current (ACC), which separates the High Antarctic from the Low Antarctic water mass, and within which are embedded the marginal ice zone and Antarctic Shelf Break Front; and the Antarctic Polar Front, which separates the Low Antarctic and the Subantarctic water masses. We used clustering to determine species' groupings with water masses, and generalized additive models to relate species' densities, biomass and diversity to distance to respective fronts. Antarctic-wide, in both periods, highest seabird densities and lowest species diversity were found in the High Antarctic water mass. In the eastern Bellingshausen, seabird density in the High Antarctic water mass was lower (as low as half that of winter) than found in other Antarctic regions. During winter, Antarctic-wide, two significant species groups were evident: one dominated by Ad??lie penguins (. Pygoscelis adeliae) (High Antarctic water mass) and the other by petrels and prions (no differentiation among water masses); in eastern Bellingshausen waters during winter, the one significant species group was composed of species from both Antarctic-wide groups. In summer, Antarctic-wide, a High Antarctic group dominated by Ad??lie penguins, a Low Antarctic group dominated by petrels, and a Subantarctic group dominated by albatross were evident. In eastern Bellingshausen waters during summer, groups were inconsistent. With regard to frontal features, Antarctic-wide in winter, distance to the ice edge was an important explanatory factor for nine of 14 species, distance to the Antarctic Polar Front for six species and distance to the Shelf Break Front for six species; however, these Antarctic-wide models could not successfully predict spatial relationships of winter seabird density (individual species or total) and biomass in the eastern Bellingshausen. Antarctic-wide in summer, distance to land/Antarctic continent was important for 10 of 18 species, not a surprising result for these summer-time Antarctic breeders, as colonies are associated with ice-free areas of coastal land. Distance to the Shelf Break Front was important for 8 and distance to the southern boundary of the ACC was important for 7 species. These summer models were more successful in predicting eastern Bellingshausen species density and species diversity but failed to predict total seabird density or biomass. Antarctic seabirds appear to respond to fronts in a way similar to that observed along the well-studied upwelling front of the California Current. To understand fully the seabird patterns found in this synthesis, multi-disciplinary at-sea investigations, including a quantified prey field, are needed. ?? 2011.

Ribic, C.A.; Ainley, D.G.; Glenn, Ford R.; Fraser, William R.; Tynan, C.T.; Woehler, E.J.

2011-01-01

432

Ice conditions on the Chesapeake Bay as observed from LANDSAT during the winters of 1977, 1978 and 1979  

NASA Technical Reports Server (NTRS)

The LANDSAT observations during the winters of 1977, 1978 and 1979, which were unusually cold in the northeastern U.S. and in the Chesapeake Bay area, were evaluated. Abnormal atmospheric circulation patterns displaced cold polar air to the south, and as a result, the Chesapeake Bay experienced much greater than normal icing conditions during these 3 years. The LANDSAT observations of the Chesapeake Bay area during these winters demonstrate the satellite's capabilities to monitor ice growth and melt, to detect ice motions, and to measure ice extent.

Foster, J. L.

1980-01-01

433

Passive thermal refugia provided warm water for Florida manatees during the severe winter of 2009-2010  

USGS Publications Warehouse

Haloclines induced by freshwater inflow over tidal water have been identified as an important mechanism for maintaining warm water in passive thermal refugia (PTR) used by Florida manatees Trichechus manatus latirostris during winter in extreme southwestern Florida. Record-setting cold during winter 2009–2010 resulted in an unprecedented number of manatee deaths, adding to concerns that PTR may provide inadequate thermal protection during severe cold periods. Hydrological data from 2009–2010 indicate that 2 canal systems in the Ten Thousand Islands (TTI) region acted as PTR and maintained warm bottom-water temperatures, even during severe and prolonged cold periods. Aerial survey counts of live and dead manatees in TTI during the winter of 2009–2010 suggest that these PTR were effective at preventing mass mortality from hypothermia, in contrast to the nearby Everglades region, which lacks similar artificial PTR and showed high manatee carcass counts. Hydrological data from winter 2008–2009 confirmed earlier findings that without haloclines these artificial PTR may become ineffective as warm-water sites. Tidal pumping of groundwater appears to provide additional heat to bottom water during low tide cycles, but the associated thermal inversion is not observed unless salinity stratification is present. The finding that halocline-driven PTR can maintain warm water even under extreme winter conditions suggests that they may have significant potential as warm-water sites. However, availability and conflicting uses of freshwater and other management issues may make halocline-driven PTR unreliable or difficult to manage during winter.

Stith, B.M.; Slone, D.H.; de Wit, M.; Edwards, H.H.; Langtimm, C.A.; Swain, E.D.; Soderqvist, L.E.; Reid, J.P.

2012-01-01

434

Relationship between seasonal cold acclimatization and mtDNA haplogroup in Japanese  

PubMed Central

Background The purpose of this study was to elucidate the interaction between mtDNA haplogroup and seasonal variation that contributes to cold adaptation. Methods There were 15 subjects (seven haplotype D subjects and eight haplotype non-D subjects). In summer and winter, the subjects were placed in an environment where the ambient temperature dropped from 27?°C to 10?°C in 30?minutes. After that, they were exposed to cold for 60?minutes. Results In summer, the decrease in rectal temperature and increase in oxygen consumption was smaller and cold tolerance was higher in the haplotype non-D group than in the haplotype D group. In winter, no significant differences were seen in rectal temperature or oxygen consumption, but the respiratory exchange ratio decreased in the haplotype D group. Conclusions The results of the present study suggest that haplogroup D subjects are a group that changes energy metabolism more, and there appears to be a relationship between differences in cold adaptability and mtDNA polymorphism within the population. Moreover, group differences in cold adaptability seen in summer may decrease in winter due to supplementation by seasonal cold acclimatization. PMID:22929588

2012-01-01

435

Cold hardiness in molluscs  

NASA Astrophysics Data System (ADS)

Molluscs inhabit all types of environments: seawater, intertidal zone, freshwater and land, and of course may have to deal with subzero temperatures. Ectotherm animals survive cold conditions by avoiding it by extensive supercooling (freezing avoidant species) or by bearing the freezing of their extracellular body fluids (freezing tolerant species). Although some studies on cold hardiness are available for intertidal molluscs, they are scarce for freshwater and terrestrial ones. Molluscs often exhibit intermediary levels of cold hardiness, with a moderate or low ability to supercool and a limited survival to the freezing of their tissues. Several factors could be involved: their dependence on water, their ability to enter dormancy, the probability of inoculative freezing in their environment, etc. Size is an important parameter in the development of cold hardiness abilities: it influences supercooling ability in land snails, which are rather freezing avoidant and survival to ice formation in intertidal organisms, which generally tolerate freezing.

Ansart, Armelle; Vernon, Philippe

2003-05-01

436

Colds and the Flu  

MedlinePLUS

... with green- or yellow-colored discharge) Sore throat Cough Sneezing Fatigue Muscle aches Headache Watery eyes Cold ... aches, especially in your back, arms and legs Cough Headache Loss of appetite What is H1N1 flu? ...

437

Beware the Bitter Cold  

MedlinePLUS

... not be available after 05/14/2015) By Robert Preidt Friday, February 13, 2015 Related MedlinePlus Pages ... risk for heat loss in cold temperatures," Dr. Robert Glatter, an emergency physician at Lenox Hill Hospital ...

438

Thermohaline fine structure in an oceanographic front from seismic reflection profiling.  

PubMed

We present acoustic images of oceanic thermohaline structure created from marine seismic reflection profiles across the major oceanographic front between the Labrador Current and the North Atlantic Current. The images show that distinct water masses can be mapped, and their internal structure imaged, using low-frequency acoustic reflections from sound speed contrasts at interfaces across which temperature changes. The warm/cold front is characterized by east-dipping reflections generated by thermohaline intrusions in the uppermost 1000 meters of the ocean. Our results imply that marine seismic reflection techniques can provide excellent spatial resolution of important oceanic phenomena, including thermohaline intrusions, internal waves, and eddies. PMID:12907798

Holbrook, W Steven; Páramo, Pedro; Pearse, Scott; Schmitt, Raymond W

2003-08-01

439

Immune responses to exercising in a cold environment.  

PubMed

Cold temperature and exercise independently impose stress on the human body that can lead to circulatory and metabolic changes, and depress the immune system. Multiple stressors applied together may amplify this immunodepression, causing greater immune impairment and heightened infection risk than with either stressor alone. As such, winter athletes and other persons who work or physically exert themselves in cold temperatures may have greater levels of stress-induced immune impairment than would be expected under mild temperatures. This review examines the literature regarding changes to physiological and immunological parameters arising from exposure to cold temperatures and to exercise. Even brief exposure to cold leads to increased levels of norepinephrine and cortisol, lymphocytosis, decreased lymphoproliferative responses, decreased levels of TH1 cytokines and salivary IgA, and increased lactate levels during exercise. Whether these changes lead to increased susceptibility to infection, as suggested by some epidemiological reports, remains to be determined. Although there is some evidence that exercising in temperatures near 5°C leads to greater immune impairment compared to exercising in milder temperatures, there is a need to explore the effects of exercise on immunity in the subfreezing conditions typically encountered by winter athletes. This is required to fully determine the extent to which performing vigorous exercise in subfreezing temperatures amplifies exercise-induced immune impairment and infection risk. PMID:21982757

LaVoy, Emily C P; McFarlin, Brian K; Simpson, Richard J

2011-12-01

440

Winter fuels report  

SciTech Connect

The Winter Fuels Report is intended to provide concise, timely information to the industry, the press, policymakers, consumers, analysis, and State and local governments on the following topics: distillate fuel oil net production, imports and stocks on a US level and for all Petroleum Administration for Defense Districts (PADD) and product supplied on a US level; propane net production, imports and stocks on a US level and for PADD`s I, II and III; natural gas supply and disposition and underground storage for the US and consumption for all PADD`s, as well as selected National average prices; residential and wholesale pricing data for heating oil and propane for those States participating in the joint Energy Information Administration (EIA)/State Heating Oil and Propane Program; crude oil and petroleum price comparisons for the US and selected cities; and a 6-10 Day, 30-Day and 90-Day outlook for temperature and precipitation and US total heating degree-days by city.

Not Available

1995-01-27

441

Winter fuels report  

SciTech Connect

The Winter Fuels Report is intended to provide concise, timely information to the industry, the press, policymakers, consumers, analysts, and state and local governments on the following topics: distillate fuel oil net production, imports and stocks for all PADD's and product supplied on a US level; propane net production, imports and stocks for Petroleum Administration for Defense Districts (PADD) I, II, and III; natural gas supply and disposition, underground storage, and consumption for all PADD's; residential and wholesale pricing data for propane and heating oil for those states participating in the joint Energy Information Administration (EIA)/State Heating Oil and Propane Program; crude oil price comparisons for the United States and selected cities; and US total heating degree-days by city. This report will be published weekly by the EIA starting the first week in October 1990 and will continue until the first week in April 1991. The data will also be available electronically after 5:00 p.m. on Thursday during the heating season through the EIA Electronic Publication System (EPUB). 12 tabs.

Not Available

1990-10-04

442

Winter fuels report  

SciTech Connect

The Winter Fuels Report is intended to provide concise, timely information to the industry, the press, policymakers, consumers, analysts, and State and local governments on the following topics: distillate fuel oil net production, imports and stocks on a US level and for all Petroleum Administration for Defense Districts (PADD) and product supplied on a US level; propane net production, imports and stocks on a US level and for PADD`s I, II, and III; natural gas supply and disposition and underground storage for the US and consumption for all PADD`s, as well as selected National average prices; residential and wholesale pricing data for heating oil and propane for those States participating in the joint Energy Information Administration (EIA)/State Heating Oil and Propane Program; crude oil and petroleum price comparisons for the US and selected cities; and a 6-10 day, 30-Day, and 90-Day outlook for temperature and precipitation and US total heating degree-days by city.

Not Available

1995-01-13

443

Winter fuels report  

SciTech Connect

The Winter Fuels Report is intended to provide concise, timely information to the industry, the press, policymakers, consumers, analysts, and State and local governments on the following topics: Distillate fuel oil net production, imports and stocks on a US level and for all Petroleum Administration for Defense Districts (PADD) and product supplied on a US level; propane net production, imports and stocks on a US level and for PADD`s I, II, and III; natural gas supply and disposition and underground storage for the US and consumption for all PADD`s; as well as selected National average prices; residential and wholesale pricing data for heating oil and propane for those States participating in the joint Energy Information Administration (EIA)/State Heating Oil and Propane Program; crude oil and petroleum price comparisons for the US and selected cities; and a 6-10 Day, 30-Day, and 90-Day outlook for temperature and precipitation and US total heating degree-days by city.

Not Available

1994-10-01

444

PHYSICS 122 LABORATORY (Winter, 2014)  

E-print Network

- 1 - PHYSICS 122 LABORATORY (Winter, 2014) COURSE GOALS 1. Learn how Chiang 235 Physics chiang@physics.ucdavis.edu 402-7113 Tony Tyson 514 Physics tyson@physics.ucdavis.edu 752-3830 TEACHING ASSISTANTS: Joe Mitchell 512

Yoo, S. J. Ben

445

PHYSICS 122 LABORATORY (Winter, 2015)  

E-print Network

- 1 - PHYSICS 122 LABORATORY (Winter, 2015) COURSE GOALS 1. Learn how Tyson 514 Physics tyson@physics.ucdavis.edu 752-3830 Xiangdong Zhu 235 Physics zhu@physics.ucdavis.edu 402-7113 TEACHING ASSISTANTS: Andrew Bradshaw 518

Yoo, S. J. Ben

446

An optimal index for measuring the effect of East Asian winter monsoon on China winter temperature  

NASA Astrophysics Data System (ADS)

Extreme cold events occur frequently in China. The authors define a representative yet simple index to reveal the monthly changes in China winter temperature associated with the East Asian winter monsoon (EAWM), which is represented by both the leading empirical orthogonal function (EOF) mode and the country-mean temperature index of Chinese 160 gauge stations. A combined technique of correlation and multivariate EOF (Corr-MVEOF) analyses is applied to capture the dominant coupled patterns of EAWM circulation system. Based on the atmospheric circulation features captured by the leading Corr-MVEOF mode, a new EAWM index referred to as CNWMI is derived by using a stepwise regression analysis. The CNWMI highlights the importance of (1) the Mongolia-Siberian High (MSH) and its southward expansion and (2) the Asia-wide meridional dipole anomaly of 500 hPa geopotential height. Compared with the 27 existing EAWM indices, the CNWMI not only best represents the leading modes of both EAWM circulation system and China winter temperature, but also reasonably tracks the intraseasonal-to-interdecadal variations of EAWM so that the monthly intensity of EAWM can be monitored conveniently. In particular, the Aleutian low (AL) is not strongly related to the MSH and may not be responsible for the variability of EAWM/MSH. Moreover, the indices that are highly correlated with the temperature over southern East Asia do not show significant relationships with the AL, which is different from the conventional concept that a strong EAWM/MSH is linked to a deepened AL. In contrast, the anomalous Australia-Maritime Continent low is in good agreement with the variation of EAWM/MSH.

Hu, Chundi; Yang, Song; Wu, Qigang

2015-02-01

447

Harnessing caustics for wave-front sensing  

Microsoft Academic Search

Scintillation in measured wave fronts adds spurious dislocations and deformations to their reconstruction. The source of the problem is caustics formed by aberrations in intermediate planes. I propose to use intentional caustics to measure wave fronts under severe conditions such as low light level, fast scale variations, large aberrations, and discontinuities in the wave front. A simple realization is based

Erez N. Ribak

2001-01-01

448

Teaching in a Cold Environment.  

ERIC Educational Resources Information Center

Instructors who teach outdoors in an environment so cold as to cause injury must satisfy program objectives while avoiding cold injury to themselves and students, help students focus on learning instead of discomfort, and alleviate some students' intense fear of the cold. Dealing with the cold successfully requires a thorough knowledge of:…

Ewert, Alan

449

Teaching in a Cold Environment.  

ERIC Educational Resources Information Center

Designed to help teachers deal with students in a cold environment, this article explains cold physiology and fundamental laws of heat; describes 14 common cold injuries and their current treatment; and lists a number of useful teaching techniques for cold environments. (SB)

Ewert, Alan

1979-01-01

450

Teaching in a Cold Environment.  

ERIC Educational Resources Information Center

The key to a successful program in a cold environment lies in dealing with the cold while still accomplishing program goals and objectives. Teachers and students must be aware of physiological and psychological reactions to the cold, cold injuries and their treatment, and techniques for staying warm. (SB)

Ewert, Alan

1979-01-01

451

Fall 2013 / Winter 2014 Dean's List Faculty of Science, Dalhousie University First Name Last Name Term(s) Erin Dempsey Winter Only  

E-print Network

Winter Only Kelsey Bennett Fall and Winter Jade Aurat Winter Only Heidi Bentley Fall and Winter Jacob Allison Barry Winter Only Paul Bissonnette Fall and Winter Melanie Barry Winter Only Stephanie Blandford

Lotze, Heike K.

452

Genetics Home Reference: Familial cold autoinflammatory syndrome  

MedlinePLUS

... the disorder. Where can I find information about diagnosis or management of familial cold autoinflammatory syndrome? These ... people use for familial cold autoinflammatory syndrome? cold hypersensitivity familial cold-induced autoinflammatory syndrome familial cold urticaria ...

453

Field Demonstration of Automated Demand Response for Both Winter and Summer Events in Large Buildings in the Pacific Northwest  

SciTech Connect

There are growing strains on the electric grid as cooling peaks grow and equipment ages. Increased penetration of renewables on the grid is also straining electricity supply systems and the need for flexible demand is growing. This paper summarizes results of a series of field test of automated demand response systems in large buildings in the Pacific Northwest. The objective of the research was two fold. One objective was to evaluate the use demand response automation technologies. A second objective was to evaluate control strategies that could change the electric load shape in both winter and summer conditions. Winter conditions focused on cold winter mornings, a time when the electric grid is often stressed. The summer test evaluated DR strategies in the afternoon. We found that we could automate both winter and summer control strategies with the open automated demand response communication standard. The buildings were able to provide significant demand response in both winter and summer events.

Piette, Mary Ann; Kiliccote, Sila; Dudley, Junqiao H.

2011-11-11

454

Effect of pre-harvest calcium sprays on post-harvest life of winter guava ( Psidium guajava L.)  

Microsoft Academic Search

Influence of pre-harvest foliar application of calcium nitrate on quality attributes of winter guava cv. ‘Sardar’ during different\\u000a interval of cold storage and post cold storage shelf-life under ambient conditions was investigated. Plants were sprayed with\\u000a calcium nitrate solutions (0.5, 1.0 and 1.5%) at colour break stage of fruit and a fruit with no treatment was control. The\\u000a fruits were

Mandal Goutam; H. S. Dhaliwal; B. V. C. Mahajan

2010-01-01

455

COLD WEATHER PLUME STUDY  

EPA Science Inventory

While many studies of power plant plume transport and transformation have been performed during the summer, few studies of these processes during the winter have been carried out. Accordingly, the U.S. Environmental Protection Agency and the Electric Power Research Institute join...

456

Microphysical simulations of polar stratospheric clouds during the 2010-2011 Arctic Winter  

NASA Astrophysics Data System (ADS)

Polar stratospheric clouds (PSCs) form in the lower stratosphere during the polar night due to the cold temperature inside the polar vortex. PSCs are important to understand because they are one of the important factors for the formation of the Antarctic ozone hole and the "mini" ozone hole over the Arctic during the winter of 2010-2011. In this work, We explore the formation and evolution of STS particles (Super-cooled Ternary Solution) and NAT (Nitric-acid Trihydrate ) particles using the SD-WACCM/CARMA model for 2010-2011 Arctic winter. SD-WACCM/CARMA is the Whole Atmosphere Community Climate Model coupled with the microphysics model (CARMA) using Specific Dynamics. The 2010-2011 Arctic winter is special because a cold Arctic vortex lasted from December until the end of March [Manney et al., 2011]. The long length of this cold period resulted in a prolonged presence of PSCs and consequently strong ozone depletion. This work includes comparison of the simulated microphysical features of PSCs with historical observations. Also, simulations and observations from MLS and Calipso showing the evolution of temperature, PSCs and related chemical species (HNO3, H2O) in 2010-2011 Arctic winter are presented.

Zhu, Y.; Toon, O. B.; Kinnison, D. E.; Lambert, A.; Brakebusch, M.

2013-12-01

457

Directly Imaging Fast Reaction Fronts  

SciTech Connect

Direct observation of fast intermetallic phase formation in Reactive Multilayer Foils (RMLFs) has been achieved. Snap-shots of the reaction appear to show development of mass-thickness contrast of the unmixed Al and Ni layers and an intermetallic phase. Electron imaging of these RMLF reaction fronts have never been attained in the past. The reaction front travels at {approx}10 meters per second as the nanoscale layers mix in an exothermic chain reaction, thus making traditional in situ electron microscopy {approx}10{sup 5} times too slow to produce such an image. The DTEM capability to produce several million electrons within nanoseconds for single-pulse imaging made this experiment possible. Additionally, the sample drive laser ensures reliable experiment initiation and repeatability. In no other way could such a high velocity event be captured at this magnification. RMLF reaction fronts continue to be analyzed via diffraction for complete phase evolution with respect to time. High quality diffraction patterns enable quantitative phase information to be obtained for future comparison to simulation.

Kim, J S; LaGrange, T B; Reed, B W; Campbell, G H; Browning, N D

2007-02-21

458

Avalanche dynamics of imbibition fronts  

NASA Astrophysics Data System (ADS)

The spatio-temporal dynamics of interfaces driven through random media has become a subject of central importance in non-equilibrium statistical mechanics in last years. A wide variety of slowly driven physical systems - vortex lines in superconductors, dislocation lines in defective crystalline solids, fracture fronts in heterogeneous materials, magnetic domain walls in disordered ferromagnets or wetting contact lines on rough substrates - exhibit a self-affine morphology and burst-like correlated motion, that arise from the interplay between competing interactions. In this context, we address here the problem of forced-flow imbibition in a disordered medium where a fluid (oil) that preferentially wets the medium displaces a resident fluid (air) at a constant flow rate. Using a high resolution fast camera, we follow the propagation of the fluid-air interface invading a disordered Hele-Shaw cell. Measuring the local waiting time fluctuations along the front during its propagation, we show that the imbibition fronts display an intermittent behavior signature of an avalanche-like dynamics. First, we will discuss the Non-Gaussian fluctuations of the global (spatialy averaged) velocity V (t) of the interface. Then, we will focus on the various scaling behavior of the local avalanches defined as spatial clusters of large local velocity. Our experimental results underline the critical behavior of the imbibition dynamics, suggesting the existence of a critical depinning transition for this process at V=0.

Santucci, Stephane

2010-03-01

459

Winter in Hellas Basin  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site]

Right now on Mars it is winter in the southern hemisphere. This means that the usually cloudy Hellas Basin is relatively free from clouds. Even though there is little cloud cover, the atmosphere is still much thicker due to the deeper basin compared to elsewhere on Mars, making image details not as crisp as when viewed through thinner atmosphere. In the center of the image are several dark streaks which originate from the side of a higher standing butte. The dark material is likely being eroded from a single layer within the cliff face. Wind has moved some of the eroded dark material to form the streaks.

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

2002-01-01

460

Interdecadal change in North Korean winter mean rainfall  

NASA Astrophysics Data System (ADS)

In the present study, it was found that there was a significant climate regime shift in 1993 from average rainfall amounts in winter (December of a year and January and February of the next year) in North Korea over the last 30 years (1982-2011). This significant climate regime shift in 1993 also appeared in empirical orthogonal function analysis conducted using the winter mean rainfall amounts observed at 26 weather observation stations in North Korea. The reason why winter mean rainfall amounts in North Korea were smaller during the period of 1994-2011 than during the period of 1982-1994 was that anomalous anticyclone was reinforced in regions near Lake Baikal while anomalous cyclone was reinforced on the sea on the east of Japan so that the winter pressure system pattern (west high-east low pattern) appeared and thus anomalous cold and dry northerlies were reinforced in most East Asian regions including North Korea. To figure out the reason why anomalous anticyclone was reinforced further in the East Asian continent in winters during the period of 1994-2011, differences in water equivalent of accumulated snow depths between the two periods were analyzed. As a result, more snow was observed in most East Asian regions during the period of 1994-2011. Therefore, anomalous anticyclone could be further reinforced in the East Asian continent because surface air temperature dropped further due to snow-albedo effect. The surface air temperature cooling deepened further in the East Asian continent during the period of 1994-2011 due to snow-albedo effect was identified through differences in sensible heat net flux between the two periods.

Choi, Ki-Seon; Kang, Sung-Dae; Kim, Hae-Dong

2013-10-01

461

The History of Winter: teachers as scientists  

NASA Astrophysics Data System (ADS)

The History of Winter (HOW) is a NASA Goddard Space Flight Center-funded teacher enrichment program that was started by Dr. Peter Wasilewski (NASA), Dr. Robert Gabrys (NASA) and Dr. Tony Gow (Cold Regions Research and Engineering Laboratory, or CRREL) in 2001 and continues with support and involvement of scientists from both the NASA Cryospheric Sciences Laboratory and CREEL. The program brings educators mostly from middle and high schools but also from state parks, community colleges and other institutions from across the US to the Northwood School (a small, private boarding school) in Lake Placid, NY for one week to learn about several facets of winter, polar, and snow research, including the science and history of polar ice core research, lake ice formation and structure, snow pack science, winter ecology, and remote sensing including current and future NASA cryospheric missions. The program receives support from the Northwood School staff to facilitate the program. The goal of the program is to create 'teachers as scientists' which is achieved through several hands-on field experiences in which the teachers have the opportunity to work with polar researchers from NASA, CRREL and partner Universities to dig and sample snow pits, make ice thin sections from lake ice, make snow shelters, and observe under-ice lake ecology. The hands-on work allows the teachers to use the same tools and techniques used in polar research while simultaneously introducing science concepts and activities to support their classroom work. The ultimate goal of the program is to provide the classroom teachers with the opportunity to learn about current and timely cryospheric research as well as to engage in real fieldwork experiences. The enthusiasm generated during the week-long program is translated into classroom activities with guidance from scientists, teachers