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1

Increased future ice discharge from Antarctica owing to higher snowfall  

NASA Astrophysics Data System (ADS)

Anthropogenic climate change is likely to cause continuing global sea-level rise, but some processes within the Earth system may mitigate the magnitude of the projected effect. Regional and global climate models simulate enhanced snowfall over Antarctica, which would provide a direct offset of the future contribution to global sea level rise from cryospheric mass loss and ocean expansion. Uncertainties exist in modelled snowfall, but even larger uncertainties exist in the potential changes of dynamic ice discharge from Antarctica. Here we show that snowfall and discharge are not independent, but that future ice discharge will increase by up to three times as a result of additional snowfall under global warming. Our results, based on an ice-sheet model forced by climate simulations through to the end of 2500, show that the enhanced discharge effect exceeds the effect of surface warming as well as that of basal ice-shelf melting, and is due to the difference in surface elevation change caused by snowfall on grounded versus floating ice. Although different underlying forcings drive ice loss from basal melting versus increased snowfall, similar ice dynamical processes are nonetheless at work in both; therefore results are relatively independent of the specific representation of the transition zone. In an ensemble of simulations designed to capture ice-physics uncertainty, the additional dynamic ice loss along the coastline compensates between 30 and 65 per cent of the ice gain due to enhanced snowfall over the entire continent. This results in a dynamic ice loss of up to 1.25 metres in the year 2500 for the strongest warming scenario.

Winkelmann, Ricarda; Levermann, Anders; Martin, Maria A.; Frieler, Katja

2013-04-01

2

Winter snowfall and summer photosynthesis for the Great Basin Desert shrubs Artemisia tridentata and Purshia tridentata.  

NASA Astrophysics Data System (ADS)

Snowfall provides the majority of soil water recharge in many western high-elevation North American ecosystems, but climate change may alter the magnitude and timing of snowfall and snow melt events thereby affecting ecosystem processes. Experiments were conducted to test hypotheses about multi-scale linkages of antecedent snow depth variation with soil water content and physiological performance of deeply-rooted shrubs in the western Great Basin Desert. Snow depth was manipulated using eight 50-year old snow fences near Mammoth Lakes, California, USA. Water potential and photosynthetic gas exchange were measured annually in early summer (1 - 2 mo following snowmelt), between 2004 and 2008 for Artemisia tridentata (Asteraceae) and Purshia tridentata (Rosaceae) on plots with increased ("+ snow"), decreased ("- snow") and ambient snow depth. Seasonal patterns were measured from May - September 2005, and four to five months after snowmelt in wet and dry years. Snow depth on +snow plots was about twice that of ambient-depth plots in most years. Depth was about 20% lower on -snow plots. Soil water content in May on +snow plots was roughly double that on ambient and 220% of that on -snow plots. Water potential patterns varied across daily, seasonal, and annual scales, but only on a few occasions was there a significant snow-depth effect. Stomatal conductance (gs) and CO2 assimilation (A) increased for several months after snowmelt in 2005, but there were only a few times when there was a snow depth effect. Photosynthetic gas exchange reflected inter-annual snow depth, but the magnitude of the variation was lower. There was a threshold response of A to October 1 - June 1 cumulative precipitation. For A. tridentata, A differed as a function of Snow Water Equivalents (SWE) across five years of measurements. Results suggest that plant water relations for these two deeply-rooted shrub species are resilient to variation in winter snow depth and subsequent spring soil water availability, and instantaneous photosynthesis may be more influenced by temperature and VPD.

Loik, M. E.; Griffith, A. B.; Alpert, H.; Concilio, A. L.; Martinson, S. J.

2011-12-01

3

Carbon dioxide ice clouds, snowfalls, and baroclinic waves in the northern winter polar atmosphere of Mars  

NASA Astrophysics Data System (ADS)

The formation of CO2 ice clouds in the northern winter polar atmosphere of Mars and their relation to baroclinic planetary waves, which dominate local dynamics, are studied using a general circulation model. The simulation shows that clouds are formed at altitudes of up to ˜ 40 km, and their occurrence correlates to a large degree with the cold phases of transient planetary waves. Ice particles formed up to ˜ 20 km can reach the surface in the form of snowfall in certain longitude regions, while in others, these particles likely sublimate in the lower warmer atmospheric layers. The simulation suggests that about a half of the seasonal ice cap is created by CO2 snow, while the remaining half by direct condensation on the surface. Thus, the occurrences of ice clouds and rates of deposition are closely linked to traveling planetary waves, indicating the possibility for the reliable forecasts of CO2 snow storms.

Kuroda, Takeshi; Medvedev, Alexander S.; Kasaba, Yasumasa; Hartogh, Paul

2013-04-01

4

Two types of matter economy for the wintering of evergreen shrubs in regions of heavy snowfall  

Microsoft Academic Search

Plant adaptation to an environment subject to heavy snowfalls was investigated in four species of evergreen shrubs growing\\u000a in a Fagus crenata forest in an area of Honshu on the Sea of Japan. These shrubs stored carbohydrates in some organs before the snowy season\\u000a and were covered with snow for 4–5 months. Aucuba japonica var. borealis, Camellia rusticana, and Ilex crenata

Yoshio Ino; Tomoyuki Maekawa; Tomohiro Shibayama; Yoshiaki Sakamaki

2003-01-01

5

The Estimation of Snowfall Rate Using Visibility  

Microsoft Academic Search

The relationship between liquid equivalent snowfall rate and visibility is investigated using data collected at the National Center for Atmospheric Research Marshall Snowfall Test Site during two winter field seasons and using theoretical relationships. The observational data include simultaneous liquid equivalent snowfall rate, crystal types, and both automated and manual visibility measurements. Theoretical relationships between liquid equivalent snowfall rate and

Roy M. Rasmussen; Jothiram Vivekanandan; Jeffrey Cole; Barry Myers; Charles Masters

1999-01-01

6

Changes in winter snowfall\\/precipitation ratio in the contiguous United States  

Microsoft Academic Search

The precipitation falling as rain or snow has different impact on regional water resources and their annual distribution. Shift from solid to liquid form of precipitation following the increase of the surface air temperatures could be quite important because such change could influence the timing of spring runoff and cause water shortage in summer. In this study, the ratio of

Song Feng; Qi Hu

2007-01-01

7

The Estimation of Snowfall Rate Using Visibility.  

NASA Astrophysics Data System (ADS)

The relationship between liquid equivalent snowfall rate and visibility is investigated using data collected at the National Center for Atmospheric Research Marshall Snowfall Test Site during two winter field seasons and using theoretical relationships. The observational data include simultaneous liquid equivalent snowfall rate, crystal types, and both automated and manual visibility measurements. Theoretical relationships between liquid equivalent snowfall rate and visibility are derived for 27 crystal types, and for `dry' and `wet' aggregated snowflakes. Both the observations and theory show that the relationship between liquid equivalent snowfall rate and visibility depends on the crystal type, the degree of riming, the degree of aggregation, and the degree of wetness of the crystals, leading to a large variation in the relationship between visibility and snowfall rate. Typical variations in visibility for a given liquid equivalent snowfall rate ranged from a factor of 3 to a factor of 10, depending on the storm. This relationship is shown to have a wide degree of scatter from storm to storm and also during a given storm. The main cause for this scatter is the large variation in cross-sectional area to mass ratio and terminal velocity for natural snow particles.It also is shown that the visibility at night can be over a factor of 2 greater than the visibility during the day for the same atmospheric extinction coefficient. Since snowfall intensity is defined by the U.S. National Weather Service using visibility, this day/night difference in visibility results in a change in snowfall intensity category caused by only whether it is day or night. For instance, a moderate snowfall intensity during the day will change to a light snowfall intensity at night, and a heavy snowfall intensity during the day will change to a moderate snowfall intensity at night, for the same atmospheric extinction coefficient.Thus, the standard relationship between snowfall intensity and visibility used by many national weather services (1/4 mile or less visibility corresponds to heavy snowfall intensity, between 5/16 and 5/8 mile corresponds to moderate intensity, and greater than 5/8 mile corresponds to light intensity) does not always provide the correct indication of actual liquid equivalent snowfall rate because of the variations in snow type and the differences in the nature of visibility targets during day and night. This false indication may have been a factor in previous ground-deicing accidents in which light snow intensity was reported based on visibility, when in fact the actual measured liquid equivalent snowfall rate was moderate to heavy.

Rasmussen, Roy M.; Vivekanandan, Jothiram; Cole, Jeffrey; Myers, Barry; Masters, Charles

1999-10-01

8

The influence of snowfall, temperature and social relationships on sleeping clusters of Japanese monkeys during winter in Shiga Heights  

Microsoft Academic Search

We studied Japanese monkeys (Macaca fuscata) of the Shiga A1 troop at their sleeping sites in Shiga Heights, Japan, for 41 nights during 3 winters. Monkeys chose their sleeping sites\\u000a in Japanese cedars and in deciduous broad-leaved forests on non-snowing nights and in Japanese cedar forests on snowing nights.\\u000a We counted 399 sleeping clusters in which 2 or more monkeys

Kazuo Wada; Eishi Tokida; Hideshi Ogawa

2007-01-01

9

Sunspots and Snowfall  

ERIC Educational Resources Information Center

Examination of the snowfall and total precipitation data for Rochester, New York, suggests a correlation with sunspot activity. Data from other locations tend to support the thesis, but the ability to predict yearly snowfall or total precipitation amounts from sunspot activity has yet to be developed. (Author/CP)

Starr, Richard R.

1978-01-01

10

Sunspots and Snowfall  

ERIC Educational Resources Information Center

|Examination of the snowfall and total precipitation data for Rochester, New York, suggests a correlation with sunspot activity. Data from other locations tend to support the thesis, but the ability to predict yearly snowfall or total precipitation amounts from sunspot activity has yet to be developed. (Author/CP)|

Starr, Richard R.

1978-01-01

11

Atlantic influence on spring snowfall over the Alps in the past 150 years  

NASA Astrophysics Data System (ADS)

Global warming is believed to be responsible for the reduction of snow amount and duration over the Alps. In fact, a rapid shortening of the snowy season has been measured and perceived by ecosystems and society in the past 30 years, despite the large year-to-year variability. This trend is projected to continue during the 21st century in the climate change scenarios with increasing greenhouse gas concentrations. Superimposed on the long-term trend, however, there is a low-frequency variability of snowfall associated with multi-decadal changes in the large-scale circulation. The amplitude of this natural low-frequency variation might be relatively large, determining rapid and substantial changes of snowfall, as recently observed. This is already known for winter snowfall over the Alps in connection with the recent tendency toward the positive phase of the North Atlantic Oscillation. In this study, we show that the low-frequency variability of Alpine spring snowfall in the past 150 years is affected by the Atlantic Multi-decadal Oscillation (AMO), which is a natural periodic fluctuation of Northern Atlantic sea surface temperature. Therefore, the recently observed spring snowfall reduction might be, at least in part, explained by the shift toward a positive AMO phase that happened in the 1990s.

Zampieri, Matteo; Scoccimarro, Enrico; Gualdi, Silvio

2013-09-01

12

Toward snowfall retrieval over land by combining satellite and in situ measurements  

NASA Astrophysics Data System (ADS)

Although snowfall is an important component of global precipitation in extratropical regions, satellite snowfall estimate is still in an early developmental stage, and existing satellite remote sensing techniques do not yet provide reliable estimates of snowfall over higher latitudes. Toward the goal of developing a global snowfall algorithm, in this study, a Bayesian technique has been tested for snowfall retrieval over land using high-frequency microwave satellite data. In this algorithm, observational data from satellite- and surface-based radars and in situ aircraft measurements are used to build the a priori database consisting of snowfall profiles and corresponding brightness temperatures. The retrieval algorithm is applied to the Advanced Microwave Sounding Unit-B data for snowfall cases that occurred over the Great Lakes region, and the results are compared with the surface radar data and daily snowfall data collected from National Weather Service stations. Although the algorithm is still at an ad hoc stage, the results show that the satellite retrievals compare well with surface measurements in the early winter season, when there is no accumulated snow on ground. However, for the late winter season, when snow constantly covers the ground, the snowfall retrievals become very noisy and show overestimation. Therefore, it is concluded that developing methods to efficiently remove surface snow cover contamination will be the major task in the future to improve the accuracy of satellite snowfall retrieval over land.

Noh, Yoo-Jeong; Liu, Guosheng; Jones, Andrew S.; Vonder Haar, Thomas H.

2009-12-01

13

Increased Tibetan Plateau snow depth: An indicator of the connection between enhanced winter NAO and late-spring tropospheric cooling over East Asia  

NASA Astrophysics Data System (ADS)

The authors present evidence to suggest that variations in the snow depth over the Tibetan Plateau (TP) are connected with changes of North Atlantic Oscillation (NAO) in winter (JFM). During the positive phase of NAO, the Asian subtropical westerly jet intensifies and the India-Myanmar trough deepens. Both of these processes enhance ascending motion over the TP. The intensified upward motion, together with strengthened southerlies upstream of the India-Myanmar trough, favors stronger snowfall over the TP, which is associated with East Asian tropospheric cooling in the subsequent late spring (April-May). Hence, the decadal increase of winter snow depth over the TP after the late 1970s is proposed to be an indicator of the connection between the enhanced winter NAO and late spring tropospheric cooling over East Asia.

Xiaoge, Xin; Zhou, Tianjun; Yu, Rucong

2010-07-01

14

Evaluation of Methods for Measurement of Snowfall and Collection of Snow for Chemical Analysis.  

National Technical Information Service (NTIS)

The study was designed to develop and compare methods for monitoring snowfall volume and chemistry throughout California. Two primary study sites at Soda Springs and Mammoth Mountain were instrumented during the winter of 1986-1987; a statewide synoptic s...

N. H. Berg B. J. McGurk D. Marks J. M. Melack D. Dawson

1989-01-01

15

Increasing Sun Protection in Winter Outdoor Recreation  

PubMed Central

Background Unprotected and excessive exposure to ultraviolet radiation (UVR) is the primary risk factor for skin cancer. Design A pair-matched, group-randomized, pre-test/post-test, quasi-experimental design, with ski resorts as the unit of randomization, tested the effectiveness of Go Sun Smart, a multi-channel skin cancer prevention program. Independent samples of guests were taken at baseline (2001) and follow-up (2002); data were analyzed in 2006. Setting and Participants A total of 6516 adult guests at 26 ski resorts in the western U.S. and Canada were recruited, consented, and interviewed on chairlifts. This study was nested within an occupational intervention for ski resort workers. Intervention Ski resorts were pair-matched and randomized to receive Go Sun Smart, which consisted of print, electronic, visual, and interpersonal skin cancer prevention messages. Main Outcome Measures Sun-protection behaviors, sunburning, recall of sun-protection messages, and the association of message exposure to sun protection. Results The difference in recall of all sun-protection messages, messages on signs and posters, and the Go Sun Smart logo was significant between the intervention and control resorts. Reported use of sun-protection practices was higher by guests at intervention ski areas using more (a higher dose of) Go Sun Smart materials. Intervention-group guests who recalled a sun-safety message were more likely to practice sun safety than intervention-group guests who did not recall a message and control-group guests. Conclusions While the mere implementation of Go Sun Smart did not produce sun-safety improvements, Go Sun Smart appeared to be effective for guests who encountered and remembered it. Many factors can work against message exposure. Signage seemed to produce the greatest increase in exposure to sun-safety messages.

Walkosz, Barbara J.; Buller, David B.; Andersen, Peter A.; Scott, Michael D.; Dignan, Mark B.; Cutter, Gary R.; Maloy, Julie A.

2009-01-01

16

Discrete thalamic lesions attenuate winter adaptations and increase body weight.  

PubMed

The midline thalamus (e.g., the paraventricular thalamic nuclei and the reuniens nucleus) of Siberian hamsters and other mammals has been reported to contain specific binding sites for melatonin, a hormone that is essential for photoperiodically induced winter adaptations such as reproductive quiescence, loss of body weight, daily torpor, and the winter molt. The first experiment investigated whether the midline thalamus is necessary for these winter adaptations. Adult Siberian hamsters received discrete neurotoxic lesions of the paraventricular thalamic nuclei or the reuniens nucleus while under pentobarbital sodium-induced anesthesia. After recovery, the hamsters were monitored for winter adaptations while they were exposed to short photoperiods (10 h light/day) for 12 wk at 22 degrees C then for 60 days at 7 degrees C. Lesions of the reuniens nucleus, but not of the paraventricular thalamic nuclei, significantly inhibited short photoperiod-induced loss of body weight and tended to increase food consumption and decrease daily torpor. The second experiment showed that lesions of the reuniens nucleus increased body weight gain compared with that in controls during exposure to long photoperiods at 22 degrees C for 16 wk. In summary, these findings show that the reuniens nucleus is an important site for regulation of body weight and suggest that lesions of the reuniens nucleus may attenuate winter metabolic adaptations by causing an increase in body weight. PMID:9249554

Purvis, C C; Duncan, M J

1997-07-01

17

An evaluation of the Wyoming gauge system for snowfall measurement  

USGS Publications Warehouse

The Wyoming snow fence (shield) has been widely used with precipitation gauges for snowfall measurement at more than 25 locations in Alaska since the late 1970s. This gauge's measurements have been taken as the reference for correcting wind-induced gauge undercatch of snowfall in Alaska. Recently, this fence (shield) was tested in the World Meteorological Organization Solid Precipitation Measurement Intercomparison Project at four locations in the United States of America and Canada for six winter seasons. At the Intercomparison sites an octagonal vertical Double Fence with a Russian Tretyakov gauge or a Universal Belfort recording gauge was installed and used as the Intercomparison Reference (DFIR) to provide true snowfall amounts for this intercomparison experiment. The intercomparison data collected were compiled at the four sites that represent a variety of climate, terrain, and exposure. On the basis of these data sets the performance of the Wyoming gauge system for snowfall observations was carefully evaluated against the DFIR and snow cover data. The results show that (1) the mean snow catch efficiency of the Wyoming gauge compared with the DFIR is about 80-90%, (2) there exists a close linear relation between the measurements of the two gauge systems and this relation may serve as a transfer function to adjust the Wyoming gauge records to obtain an estimate of the true snowfall amount, (3) catch efficiency of the Wyoming gauge does not change with wind speed and temperature, and (4) Wyoming gauge measurements are generally compatible to the snowpack water equivalent at selected locations in northern Alaska. These results are important to our effort of determining true snowfall amounts in the high latitudes, and they are also useful for regional hydrologic and climatic analyses.

Yang, D.; Kane, D. L.; Hinzman, L. D.; Goodison, B. E.; Metcalfe, J. R.; Louie, P. Y. T.; Leavesley, G. H.; Emerson, D. G.; Hanson, C. L.

2000-01-01

18

An evaluation of the Wyoming Gauge System for snowfall measurement  

NASA Astrophysics Data System (ADS)

The Wyoming snow fence (shield) has been widely used with precipitation gauges for snowfall measurement at more than 25 locations in Alaska since the late 1970s. This gauge's measurements have been taken as the reference for correcting wind-induced gauge undercatch of snowfall in Alaska. Recently, this fence (shield) was tested in the World Meteorological Organization Solid Precipitation Measurement Intercomparison Project at four locations in the United States of America and Canada for six winter seasons. At the Intercomparison sites an octagonal vertical Double Fence with a Russian Tretyakov gauge or a Universal Belfort recording gauge was installed and used as the Intercomparison Reference (DFIR) to provide true snowfall amounts for this Intercomparison experiment. The Intercomparison data collected were compiled at the four sites that represent a variety of climate, terrain, and exposure. On the basis of these data sets the performance of the Wyoming gauge system for snowfall observations was carefully evaluated against the DFIR and snow cover data. The results show that (1) the mean snow catch efficiency of the Wyoming gauge compared with the DFIR is about 80-90%, (2) there exists a close linear relation between the measurements of the two gauge systems and this relation may serve as a transfer function to adjust the Wyoming gauge records to obtain an estimate of the true snowfall amount, (3) catch efficiency of the Wyoming gauge does not change with wind speed and temperature, and (4) Wyoming gauge measurements are generally compatible to the snowpack water equivalent at selected locations in northern Alaska. These results are important to our effort of determining true snowfall amounts in the high latitudes, and they are also useful for regional hydrologic and climatic analyses.

Yang, Daqing; Kane, Douglas L.; Hinzman, Larry D.; Goodison, Barry E.; Metcalfe, John R.; Louie, Paul Y. T.; Leavesley, George H.; Emerson, Douglas G.; Hanson, Clayton L.

2000-09-01

19

Decreased winter severity increases viability of a montane frog population.  

PubMed

Many proximate causes of global amphibian declines have been well documented, but the role that climate change has played and will play in this crisis remains ambiguous for many species. Breeding phenology and disease outbreaks have been associated with warming temperatures, but, to date, few studies have evaluated effects of climate change on individual vital rates and subsequent population dynamics of amphibians. We evaluated relationships among local climate variables, annual survival and fecundity, and population growth rates from a 9-year demographic study of Columbia spotted frogs (Rana luteiventris) in the Bitterroot Mountains of Montana. We documented an increase in survival and breeding probability as severity of winter decreased. Therefore, a warming climate with less severe winters is likely to promote population viability in this montane frog population. More generally, amphibians and other ectotherms inhabiting alpine or boreal habitats at or near their thermal ecological limits may benefit from the milder winters provided by a warming climate as long as suitable habitats remain intact. A more thorough understanding of how climate change is expected to benefit or harm amphibian populations at different latitudes and elevations is essential for determining the best strategies to conserve viable populations and allow for gene flow and shifts in geographic range. PMID:20421473

McCaffery, Rebecca M; Maxell, Bryce A

2010-04-26

20

Response of Rates and Sources of Ecosystem CO2 Efflux to Increasing Levels of Winter Snow Depth in the High Arctic of Northwest Greenland  

NASA Astrophysics Data System (ADS)

Arctic soils contain vast amounts of organic carbon (C) that range in age from modern to ancient. These soil C pools may be especially vulnerable to changes in conditions; especially increases in winter snowfall, as deeper snow will insulate soils in winter, and add moisture in summer. While, snowfall is increasing in many parts of the Arctic, how increases in winter precipitation affect C cycling in the High Arctic is largely unknown. In this project, we used a long-term snowpack manipulation to develop a better understanding of current and future soil C cycling under conditions of deep winter snow pack and the associated feedbacks to future atmospheric CO2 levels. We examined the effects of three levels of winter snowpack (ambient (0.25 m), ×2, ×4) on the timing, magnitude and sources of ecosystem CO2 efflux and soil microclimate in prostrate dwarf-shrub tundra on patterned ground in the High Arctic of NW Greenland. From June to August 2010 and 2011 we monitored ecosystem CO2 efflux and soil CO2 concentrations (LI-COR 800 & 840) together with soil temperature and moisture daily and the radiocarbon (14C) content of CO2 monthly. The 14C content of CO2 can be used to infer the dominant source of CO2 (plant vs. microbially-respired) as well as the age of microbially-respired CO2. Initial results indicate that during the 2010 sampling period (Jun 28 - Aug 16), daily CO2 emissions from vegetated areas were higher under ×4 ambient snowpack relative to ambient snowpack (84.9 vs. 53.1 mmol m-2 d-1), but lower under ×2 ambient snowpack (56.7 mmol m-2 d-1). CO2 emissions from bare areas increased with snowpack depth from ambient (8.6 mmol m-2 d-1) to ×2 ambient snowpack (16.5 mmol m-2 d-1) to x4 ambient snowpack (18.9 mmol m-2 d-1). Midsummer ecosystem CO2 emissions were dominated by modern C; additional 14C measurements are in progress. Our findings indicate that increases in snowpack may stimulate C loss from this high arctic ecosystem - probably facilitated by higher soil moisture - providing positive feedback to rising atmospheric CO2 levels.

Thomas, J. S.; Lupascu, M.; Xu, X.; Maseyk, K. S.; Welker, J. M.; Czimczik, C. I.

2011-12-01

21

Wintering range expansion and increase of sika deer in Nikko in relation to global warming  

Microsoft Academic Search

This paper analyzes the expansion of sika deer (Cervus nippon) wintering ground in relation to global warming in Nikko, central Honshu, Japan. The sika wintering ground of 1993-1994 expanded toward snowy areas compared to that of 1980-1982, and the sika density increased both in new and traditional wintering grounds. Information on snow accumulation and winter deer distribution was collected by

Yuchun Li; Naoki Maruyama; Masaaki Koganezawa; Nobuo Kanzaki

1996-01-01

22

Snowfall, snowpack, and meltwater chemistry  

Technology Transfer Automated Retrieval System (TEKTRAN)

Biogeochemical cycling of nutrients and pollutants in the environment is significantly affected by the occurrence of snowfall and snowpacks. Snowpacks can be viewed as reservoirs of chemicals that, unlike substances dissolved in rainfall, can be largely stored for significant periods of time during...

23

Climatological characterization of wind and snowfall in Minnesota and assessing the impacts of living snow fences  

NASA Astrophysics Data System (ADS)

Blowing and drifting snow on roadways is a common occurrence in Minnesota due to the topographic, vegetative, and winter climate characteristics of this area. Through proper road design and the use of snow fences this problem can be alleviated, however snowfall and wind climatological information must first be analyzed. Archived climatological records for locations in Minnesota were recently compiled. Snowfall time series data show a statistically significant increase of 28cm in the annual total since 1890. The increase is shown to occur for November--December while February and March show a decrease. This increase is largely due to an increase in the frequency of snow events less than 10cm. Wind data from federal observing sites in Minnesota show a correlation to landscape variability, with a high frequency of higher wind speeds in western and southern Minnesota. A snow relocation factor needed to quantify seasonal snow transport was calculated and shows a strong dependence on the wind speed distribution. A case study of the 2000--01 winter season allowed for examination of snow storage and agricultural implications of three living snow fence designs in southern Minnesota (two 8-row strips of corn, twin-row honeysuckle, single-row honeysuckle/red cedar). For a winter with high seasonal snowfall and spring rainfall, results of snow storage and modeled seasonal snow transport show good agreement for the two corn row strips. However, snow storage totaled approximately 50% of the modeled snow transport for the honeysuckle fence designs, which appeared to reach storage capacity prior to the end of the snow season. A key factor is the absence of a bottom gap, which promotes leeward displacement of the downwind drift and prevents snow deposition on the fence. Soil temperature and frost depth data show a moderation in temperatures and a decrease in freezing depth with an increase in associated snowpack depth. Post-season soil moisture shows no significant variability with respect to over-winter snowpack due to the anomalous rainfall received during and after snowmelt. Finally, crop yield samples show a 6%--36% reduction adjacent to the fence, but also show a relatively quick recovery.

Shulski, Martha Elizabeth Durr

24

Seasonal small-scale spatial variability in alpine snowfall and snow accumulation  

NASA Astrophysics Data System (ADS)

In mountainous regions, snow accumulation on the ground is crucial for mountain hydrology and water resources. The present study investigates the link between the spatial variability in snowfall and in snow accumulation in the Swiss Alps. A mobile polarimetric X-band radar deployed in the area of Davos (Switzerland) collected valuable and continuous information on small-scale precipitation for the winter seasons of 2009/2010 and 2010/2011. Local measurements of snow accumulation were collected with airborne laser-scanning for the winters of 2007/2008 and 2008/2009. The spatial distribution of snow accumulation exhibits a strong interannual consistency that can be generalized over the winters in the area. This unique configuration makes the comparison of the variability in total snowfall amount estimated from radar and in snow accumulation possible over the diverse winter periods. As expected, the spatial variability, quantified by means of the variogram, is shown to be larger in snow accumulation than in snowfall. However, the variability of snowfall is also significant, especially over the mountain tops, leads to preferential deposition during snowfall and needs further investigation. The higher variability at the ground is mainly caused by snow transport.

Scipión, D. E.; Mott, R.; Lehning, M.; Schneebeli, M.; Berne, A.

2013-03-01

25

Climate change projection of snowfall in the Colorado River Basin using dynamical downscaling  

NASA Astrophysics Data System (ADS)

Recent observations show a decrease in the fraction of precipitation falling as snowfall in the western United States. In this work we evaluate a historical and future climate simulation over the Colorado River Basin using a 35 km continuous 111 year simulation (1969-2079) of the Weather Research and Forecasting (WRF) regional climate model with boundary forcing from the Hadley Centre for Climate Prediction and Research/Met Office's HadCM3 model with A2 emission scenario. The focus of this work is to (1) evaluate the simulated spatiotemporal variability of snowfall in the historical period when compared to observations and (2) project changes in snowfall and the fraction of precipitation that falls as snow during the 21st century. We find that the spatial variability in modeled snowfall in the historical period (1981-2005) is realistically represented when compared to observations. The trends of modeled snowfall are similar to the observed trends except at higher elevations. Examining the continuous 111 year simulation, we find the future projections show statistically significant increases in temperature with larger increases in the northern part of the basin. There are statistically insignificant increases in precipitation, while snowfall shows a statistically significant decrease throughout the period in all but the highest elevations and latitudes. The fraction of total precipitation falling as snow shows statistically significant declines in all regions. The strongest decrease in snowfall is seen at high elevations in the southern part of the basin and low elevations in the northern part of the basin. The regions of most intense decreases in snow experience a decline of approximately 50% in snowfall throughout the 111 year simulation period. The regions of strongest declines in snowfall roughly correspond to the region of migration of the zero degree Celsius line and emphasize snowfall dependence on both altitude and latitude.

Wi, Sungwook; Dominguez, Francina; Durcik, Matej; Valdes, Juan; Diaz, Henry F.; Castro, Christopher L.

2012-05-01

26

Ecosystem CO2 production during winter in a Swedish subarctic region: the relative importance of climate and vegetation type  

Microsoft Academic Search

General circulation models consistently predict that regional warming will be most rapid in the Arctic, that this warming will be predominantly in the winter season, and that it will often be accompanied by increasing snowfall. Paradoxically, despite the strong cold season emphasis in these predictions, we know relatively little about the plot and landscape-level controls on tundra biogeochemical cycling in

PAUL G ROGAN; S VEN J ONASSON

2006-01-01

27

On the future reduction of snowfall in western and central Europe  

NASA Astrophysics Data System (ADS)

Large parts of western and central Europe face a 20-50 % future reduction in snowfall on Hellmann days (days with daily-mean temperatures below freezing). This strong reduction occurs in addition to the expected 75 % decrease of the number of Hellmann days near the end of the twenty first century. The result is insensitive to the exact freezing-level threshold, but is in sharp contrast with the winter daily precipitation, which increases under most global warming scenarios. Not only climate model simulations show this. Observational records also reveal that probabilities for precipitation on Hellmann days have been larger in the past. The future reduction is a consequence of the freezing-level threshold becoming a more extreme quantile of the temperature distribution in the future. Only certain circulation types permit these quantiles to be reached, and it is shown that these have intrinsically low precipitation probability.

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

2012-11-01

28

A robust neural network system ensemble approach for detecting and estimating snowfall from the advanced microwave sounding unit  

NASA Astrophysics Data System (ADS)

The principal intent of this research is to: (a) investigate the potential of passive microwave data from AMSU in detecting snowfall events and in measuring their intensity, and (b) evaluate the effect of both land cover and atmospheric conditions on the retrieval accuracy. A neural-network-based model has been developed and has shown a great potential in detecting and estimating the intensity of snowfall events. This algorithm has been applied for different snow storms occurred in four winter seasons in the North-East of United States. Additional information such as cloud cover and air temperature were added to the process to reduce misidentified snowfall pixels. Only pixels with cloud cover and falling within a specific range of temperature are presented to the snowfall detection model. Surface temperature collected from ground station-based observations and archived by the National Climatic Data Center (NCDC) were used for this test. Different heavy storm events and non-snowfall observations that occurred at the same time as AMSU acquisition were selected. Hourly snow accumulation data collected by the NCDC were used as truth data to train and validate the model. The results indicate that the neural-network-based model provides a significant improvement in snowfall detection accuracy over existing satellite-based methods. Most importantly, the neural network system product is a map indicating the snowfall area and the respective intensity level for each pixel.

Mejia, Yajaira

29

An exceptionally heavy snowfall in Northeast china: large-scale circulation anomalies and hindcast of the NCAR WRF model  

NASA Astrophysics Data System (ADS)

In Northeast China (NEC), snowfalls usually occur during winter and early spring, from mid-October to late March, and strong snowfalls rarely occur in middle spring. During 12-13 April 2010, an exceptionally strong snowfall occurred in NEC, with 26.8 mm of accumulated water-equivalent snow over Harbin, the capital of the most eastern province in NEC. In this study, the major features of the snowfall and associated large-scale circulation and the predictability of the snowfall are analyzed using both observations and models. The Siberia High intensified and shifted southeastward from 10 days before the snowfall, resulting in intensifying the low-pressure system over NEC and strengthening the East Asian Trough during 12-13 April. Therefore, large convergence of water vapor and strong rising motion appeared over eastern NEC, resulting in heavy snowfall. Hindcast experiments were carried out using the NCAR Weather Research and Forecasting (WRF) model in a two-way nesting approach, forced by NCEP Global Forecast System data sets. Many observed features including the large-scale and regional circulation anomalies and snowfall amount can be reproduced reasonably well, suggesting the feasibility of the WRF model in forecasting extreme weather events over NEC. A quantitative analysis also shows that the nested NEC domain simulation is even better than mother domain simulation in simulating the snowfall amount and spatial distribution, and that both simulations are more skillful than the NCEP Global Forecast System output. The forecast result from the nested forecast system is very promising for an operational purpose.

Wang, Huijun; Yu, Entao; Yang, Song

2011-06-01

30

Improving Snowfall Forecasting by Diagnosing Snow Density  

Microsoft Academic Search

Current prediction of snowfall amounts is accomplished either by using empirical techniques or by using a standard modification of liquid equivalent precipitation such as the 10-to-1 rule. This rule, which supposes that the depth of the snowfall is 10 times the liquid equivalent (a snow ratio of 10:1, reflecting an assumed snow density of 100 kg m23), is a particularly

Paul J. Roebber; Sara L. Bruening; David M. Schultz; John V. Cortinas

2003-01-01

31

A shorter snowfall season associated with higher air temperatures over northern Eurasia  

NASA Astrophysics Data System (ADS)

The temperature sensitivity of the snowfall season (start, end, duration) over northern Eurasia (the former USSR) is analyzed from synoptic records of 547 stations from 1966 to 2000. The results find significant correlations between temperature and snowfall season at approximately 56% of stations (61% for the starting date and 56% for the ending date) with a mean snowfall season duration temperature sensitivity of -6.2 days °C-1 split over the start (2.8 days) and end periods (-3.4 days). Temperature sensitivity was observed to increase with stations’ mean seasonal air temperature, with the strongest relationships at locations of around 6?°C temperature. This implies that increasing air temperature in fall and spring will delay the onset and hasten the end of snowfall events, and reduces the snowfall season length by 6.2 days for each degree of increase. This study also clarifies that the increasing trend in snowfall season length during 1936/37-1994 over northern European Russia and central Siberia revealed in an earlier study is unlikely to be associated with warming in spring and fall seasons.

Ye, Hengchun; Cohen, Judah

2013-03-01

32

21st century snowfall changes over the French Alps : the role of temperature  

NASA Astrophysics Data System (ADS)

Mountainous areas are among the regions where particularly severe climate changes are expected to occur within the next century. Snowfall changes in those regions could have widespread hydrological, ecological and economic impacts. Fine topography influence on the local climate in those regions has to be taken into account to produce realistic climate projections, especially for precipitations. Within the recent SCAMPEI (Climate Scenarios for Mountain Areas : Extreme Events, Snow Cover and Uncertainties) project, dedicated to climate change over French mountainous areas, a very large ensemble of high-resolution regional climate projections has been analyzed. They were obtained either through statistical or dynamical downscaling. The statistical downscaling method is based on weather typing and is applied to 14 models from the Coupled Model Intercomparison Project 3 and to a set of projections from the atmospheric global circulation model of Météo-France, to reach a horizontal resolution of 8km over France. High resolution regional climate projections come from three specific models at 12km used in SCAMPEI and also from 16 models from the ENSEMBLES European project (at a 25km horizontal resolution over Europe). An evaluation of the robustness of snowfall changes over the French Alps simulated during the 21st century and the associated uncertainties will be presented. In particular, the role of temperature changes on snowfall changes will be discussed. At the beginning and at the end of the cold season, temperature change is found to be an important source of spread in snowfall changes. However, no link is found between temperature and snowfall changes in January and February. For early and late winter, the relative change in snowfall per degree Kelvin is a robust quantity in the sense that its sensitivity to the bias correction step, the projection period or the greenhouse gas emission scenario is low.

Piazza, M.; Boe, J.; Page, C.; Sanchez-Gomez, E.; Terray, L.

2012-04-01

33

Variability and trends of total precipitation and snowfall over the United States and Canada  

SciTech Connect

The biases and large-scale inhomogeneities in the time series of measured precipitation and snowfall over the United States and Canada are discussed and analyzed. The spatial statistical characteristics of monthly and annual snowfall and total precipitation are investigated and parameterized. After adjustments and selection of the best' network, reliable first guess' estimates of North American snowfall and precipitation are obtained. Century-long time series of unbiased annual precipitation over the regions to the south of 55[degrees]N and 40-year time series of unbiased area-averaged annual precipitation and snowfall for all of North America are developed. The analysis of their trends shows the following. (1) During the last 100 years, annual precipitation has increased in southern Canada (south of 55[degrees]N) by 13% and in the contiguous United States by 4%; however, the main domain of this century-scale precipitation increase is eastern Canada and adjacent to it northern regions of the United States. (2) Up to a 20% increase has occurred in annual snowfall and rainfall during the last four decades in Canada north of 55[degrees]N. The relationships between century-long precipitation time series over North America with Northern Hemisphere surface air temperature and the South Oscillation index (SOI) are investigated. It is shown that ENSO (negative anomaly of SOI) is usually accompanied by an increase of precipitation whenever it affects the United States (especially in the southwestern region of the country).

Groisman, P.Y. (State Hydrological Institute, St. Petersburg (Russian Federation)); Easterling, D.R. (Global Climate Laboratory, Asheville, NC (United States))

1994-01-01

34

The 8th-10 th January 2009 snowfalls: a case of Mediterranean warm advection event  

NASA Astrophysics Data System (ADS)

From 8 th to 10 th of January 2009, significant snowfalls were reported in many areas of the Iberian Peninsula and the Balearic Islands. This relevant event was very important from the meteorological and social impact point of views. The snow affected many zones, especially the regions of Madrid, Castilla & León and Castilla-La Mancha (Spanish central plateau) with the persistence and thickness of solid precipitation. Up to twenty-five centimetres of snow were reported in some places. On 9th of January the snowfalls caused great social and media impact due to the fact that they took place in the early hours in the Madrid metropolitan areas, affecting both air traffic and land transport. The "Madrid-Barajas" airport was closed and the city was collapsed during several hours. A study of this situation appears in the poster. The snowstorm was characterized by the previous irruption of an European continental polar air mass, that subsequently interacted with a wet and warm air mass of Mediterranean origin, all preceded by low level easterly flows. This type of snowfall is called "warm advection". These winter situations are very efficient from precipitation point of view, generating significant snowfalls and affecting a lot of areas.

Aguado, F.; Ayensa, E.; Barriga, M.; Del Hoyo, J.; Fernández, A.; Garrido, N.; Martín, A.; Martín, F.; Roa, I. Martínez, A.; Pascual, R.

2009-09-01

35

Cold temperature increases winter fruit removal rate of a bird-dispersed shrub.  

SciTech Connect

Kwit, C., D. J. Levey; C. H. Greenberg, S. F. Pearson, J.P. McCarty, and S. Sargent. Cold temperature increases winter fruit removal rate of a bird-dispersed shrub. Oecologia. 139:30-34. Abstract: We tested the hypothesis that winter removal rates of fruits of wax myrtle, Myrica cerifera, are higher in colder winters. Over a 9-year period, we monitored M. cerifera fruit crops in 13 0.1-ha study plots in South Carolina, U.S.A. Peak ripeness occurred in November, whereas peak removal occurred in the coldest months, December and January. Mean time to fruit removal within study plots was positively correlated with mean winter temperatures, thereby supporting our hypothesis. This result, combined with the generally low availability of winter arthropods, suggests that fruit abundance may play a role in determining winter survivorship and distribution of permanent resident and short-distance migrant birds. From the plant's perspective, it demonstrates inter-annual variation in the temporal component of seed dispersal, with possible consequences for post-dispersal seed and seedling ecology.

Charles Kwit; Douglas J. Levey; Cathryn H. Greenberg; Scott F. Pearson; John P. McCarty; Sarah Sargent

2004-01-10

36

Taiwan Snowfall Activity and Its Association with Asian Dust Storm from 1995 to 2009  

NASA Astrophysics Data System (ADS)

While snowfall in the subtropical zone is rare, Yushan is the most famous snow spot in Taiwan. When it is snowing in mountains, people are experiencing unusually cold and wet weather in Taiwan. In this paper, snowfall activity from 1995 to 2009 and the related atmosphere circulation are examined with Taiwan CWB's weather station observations and the NCEP/DOE reanalysis atmospheric data. Also, Asian dust storm activity and PM10 concentration in Taiwan are examined with SYSNOP data and the EPA' s air quality monitoring station observation data. Our analyses show that snowfall activity is closely related to the position of EAT (East Asia Trough), strength of WPH (West Pacific High) and Asian dust storm active. Asian dust is a good ice nucleation for heterogenous freezing. Climatologically, the existence of a large-scale dry zone over mid-latitudes of Asia provides a favorable environment for the frequent occurrences of dust events and subsequent dust transport across Asia, which provides a huge amount of ice nucleation. In active year, when the EAT was shifted eastward and the strength of WPH was increased, an anticyclone anomalous occurred in the West Pacific. This anticyclone introduced anomalous southwesterly flows along the southeast cost of China and over Taiwan, resulting in a wetter-than-normal atmosphere and meanwhile the PM10 concentrations higher than usual which in favor of snowfall activity. Alternatively in inactive years, it resulted in a drier-than-normal atmosphere and a sluggish snowfall season. The SVD analysis has shown that the relation be tween the position of EAT and the anomalous pressure dipoles is rather robust, at least in those years that Asian dust storm activity is particularly strong while snowfall activity is weak (e.g., 1999, 2001, and 2002) or weak in dust storm activity and strong in snowfall activity (e.g., 19998, 2003, 2005 and 2008).

Tsai, L.; Wang, Z.; Liu, K.

2011-12-01

37

Detecting snowfall over land by satellite high-frequency microwave observations: The lack of scattering signature and a statistical approach  

NASA Astrophysics Data System (ADS)

has been long believed that the dominant microwave signature of snowfall over land is the brightness temperature decrease caused by ice scattering. However, our analysis of multiyear satellite data revealed that on most of occasions, brightness temperatures are rather higher under snowfall than nonsnowfall conditions, likely due to the emission by cloud liquid water. This brightness temperature increase masks the scattering signature and complicates the snowfall detection problem. In this study, we propose a statistical method for snowfall detection, which is developed by using CloudSat radar to train high-frequency passive microwave observations. To capture the major variations of the brightness temperatures and reduce the dimensionality of independent variables, the detection algorithm is designed to use the information contained in the first three principal components resulted from Empirical Orthogonal Function (EOF) analysis, which capture ~99% of the total variances of brightness temperatures. Given a multichannel microwave observation, the algorithm first transforms the brightness temperature vector into EOF space and then retrieves a probability of snowfall by using the CloudSat radar-trained look-up table. Validation has been carried out by case studies and averaged horizontal snowfall fraction maps. The result indicated that the algorithm has clear skills in identifying snowfall areas even over mountainous regions.

Liu, Guosheng; Seo, Eun-Kyoung

2013-02-01

38

Sensitivity of Lake-Enhanced Snowfall to Lake Ice Cover in the Great Lakes Region  

NASA Astrophysics Data System (ADS)

The Great Lakes exert a significant influence on the regional climate of northern United States and southern Canada, including enhancement of cold-season precipitation on and downwind of the leeward shores. Lake-enhanced snowfall occurs when air that is significantly colder than the lake's surface temperature travels over the lake. Enhanced surface sensible and latent heat fluxes relative to the surrounding land surface result in moistening and destabilization of the atmosphere and subsequent development of low-level convection. In the Great Lakes region, lake-enhanced snow occurs during late fall through early winter, with decreasing numbers of events in the late winter due to the formation of widespread lake ice. Lake ice reduces both sensible and latent heat fluxes from the surface, thereby increasing atmospheric stability and reducing lake induced convection. The degree to which ice coverage may change in future climate scenarios is largely unknown, but it is clear that any change to the fraction and duration of lake ice coverage will have an effect on lake-atmosphere interaction and the development and intensity of lake-enhanced precipitation. This study uses the NCAR Weather, Research, and Forecasting (WRF) model to examine how changes in Great Lakes fractional ice coverage affect the presence, intensity, and quantity of lake-enhanced precipitation. Sensitivity studies are used to evaluate the evolution and change in intensity of lake-enhanced snowfall in the Great Lakes region for scenarios that include (1) lake ice cover obtained from analysis fields (control simulation), (2) ice-free lakes, and (3) 100% ice coverage. Distinct lake-effect snow bands were observed in both the control and ice-free simulations, with placement of these bands further to the south and propagating further inland in the ice-free case. Melted precipitation totals increased on the order of 10 mm for ice-free lakes along the southern edges of Lake Superior, Lake Erie, and the eastern coast of Lake Ontario, while complete ice coverage extinguished nearly all lake-effect snow bands.

Wright, D. M.; Posselt, D. J.; Steiner, A. L.

2011-12-01

39

Winter Storms in the Central Himalayas  

Microsoft Academic Search

Based on observations from a hydrometeorological network on the eastern slopes of the Annapurna Range, nearly all the annual precipitation at low elevations (< 2000 m MSL) in Nepal is in liquid form, even during the winter. However, high elevations (> 3000 m MSL) can receive up to 40% of their annual precipitation as snowfall during the winter, with the

Timothy J. LANG; Ana P. BARROS

2004-01-01

40

The criteria of heavy snowfalls in Russia  

NASA Astrophysics Data System (ADS)

Nowadays, unfortunately, the number of victims of natural hazards doesn't decrease in Russia. There are many reasons of that situation - both geographical and human. Russia is one of the most spread countries in the world and it has the big number of different types of natural phenomena, which can cause natural disaster. One of the reasons is the fact that the criteria of which meteorological or hydrological hazards can cause an emergency situation are equal for the whole territory of Russia. .And that's why many dangerous situations are underestimated. The analysis of the distribution of criteria in Russia shows that only temperature phenomena (such as frost or heat) have really space differentiation. According to directive documents in Russia, the criteria of heavy snowfall in all the territory of Russia is 20 mm per 12 hours - from subtropical to arctic regions. But the socio-economical and climatic conditions are so different, that using this one criteria is not rational at all. In the investigation held the author developed the method of differentiation the territoty of Russia and proposed different criteria of heavy snowfalls for chosen regions. The method is based, on one hand on analysis of 30-years statistics of natural disasters in Russia, and on other hand on the analysis of the density of population and the mean quantity of precipitation in the cold period in Russia. The geographical zoning of Russia was conduct and clusters with equal parameters were determined. That means that in these areas the same hydro meteorological characteristics can be used for. The new criteria for the number of natural phenomena (such as hale, snowfalls etc) were found. The analysis of this criteria of heavy snowfalls showed, that on 70 the territory of Russia this criteria (20 mm per 12 hours) is overstated. In the most of the big cities (according to the statistics and calculated data) in different climatic regions this criteria should be much lower - from 8 to 10 mm per 12 hours.

Gavrilova, Sofia

2013-04-01

41

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.

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

1970-01-01

42

An evaluation of the Wyoming gauge system for snowfall measurement  

Microsoft Academic Search

The Wyoming snow fence (shield) has been widely used with precipitation gauges for snowfall measurement at more than 25 locations in Alaska since the late 1970s. This gauge's measurements have been taken as the reference for correcting wind-induced gauge undercatch of snowfall in Alaska. Recently, this fence (shield) was tested in the World Meteorological Organization Solid Precipitation Measurement Intercomparison Project

Daqing Yang; Douglas L. Kane; Larry D. Hinzman; Barry E. Goodison; John R. Metcalfe; Paul Y. T. Louie; George H. Leavesley; Douglas G. Emerson; Clayton L. Hanson

2000-01-01

43

An evaluation of the Wyoming Gauge System for snowfall measurement  

Microsoft Academic Search

The Wyoming snow fence (shield) has been widely used with precipitation gauges for snowfall measurement at more than 25 locations in Alaska since the late 1970s. This gauge's measurements have been taken as the reference for correcting wind-induced gauge undercatch of snowfall in Alaska. Recently, this fence (shield) was tested in the World Meteorological Organization Solid Precipitation Measurement Intercomparison Project

Daqing Yang; Douglas L. Kane; Larry D. Hinzman; Barry E. Goodison; John R. Metcalfe; Paul Y. T. Louie; George H. Leavesley; Douglas G. Emerson; Clayton L. Hanson

2000-01-01

44

[Distribution of Pges contents and its factors in snowfall and snow cover over the arid region in Changji City].  

PubMed

This paper was to select a small-medium sized City, Changji city, over the arid region, study the distribution of platinum group metals(PGEs) contents and influencing factors in snowfall and snow cover. Samples were analysed by ICP-MS. The results revealed that the annual contents of Rh, Pd and Pt in snowfall were on the average value of 0.43 ng.L-1 ranging from not detected to 2.24 ng.L-1 , 60.07 ng.L-1 ranging from 46.66 to 84.25 ng.L-1 and 4.54 ng.L-1 ranging from 3.02 ng.L-1 to 6.38 ng.L-1 respectively. The difference of PGEs levels was found in different occurrences of snowfall, tended to increase before snowfall due to the longer arid days. PGEs contents maybe influenced by the amount of snowfall, the less snowfall, the higher PGEs contents reflected. The annual levels of Rh, Pd and Pt in snow cover were in the range of 2.50-18.80 ng.L-1 (av. 6.65 ng.L-1), 46.83-199.20 ng.L-1 (av. 83.45 ng.L-1) ,4. 27-13.78 ng.L-1 (av. 8.17 ng.L-1) respectively. PGEs content in snow cover were far higher than that of snowfall, PGEs in snowfall were only obtained from atmospheric PGEs rinsed by single time of snowfall, while PGEs were not only from the accumulation of PGEs in frequent times of snowfall and the snow cover under the long time exposure, but also continuously accepted the PGEs from atmospheric dry deposition. PGEs content of snow cover in all sampling sites were demonstrated as follows: traffic area > residential-culture-education district > square of park > suburban farmland. the input way of PGEs in snow cover was found a remarkable difference with the amount of input within different function areas, which was the main reason caused that PGEs content of snow cover in each function area varied and had a certain regularity. PMID:23668114

Liu, Yu-Yan; Liu, Hao-Feng; Zhang, Lan

2013-02-01

45

Snowfall-Driven Growth in East Antarctic Ice Sheet Mitigates Recent Sea-Level Rise  

Microsoft Academic Search

Satellite radar altimetry measurements indicate that the East Antarctic ice-sheet interior north of 81.6°S increased in mass by 45 +\\/- 7 billion metric tons per year from 1992 to 2003. Comparisons with contemporaneous meteorological model snowfall estimates suggest that the gain in mass was associated with increased precipitation. A gain of this magnitude is enough to slow sea-level rise by

Curt H. Davis; Yonghong Li; Joseph R. McConnell; Markus M. Frey; Edward Hanna

2005-01-01

46

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

47

The Changing Character of Winter Precipitation over the Western United States  

NASA Astrophysics Data System (ADS)

As climate warms over the topographically complex western United States (US), it will likely bring changes in the character of precipitation, including its intensity, frequency and phase. We analyze future precipitation projections using regional climate models (RCMs) driven by IPCC AR4 global climate models (GCMs) for the 20th and 21st centuries. We find very small changes in total precipitation, but statistically significant decrease in future snowfall throughout the period, with strongest decrease in snowfall at high elevations in lower latitudes and low elevations in higher latitudes (within the western US). The regions of strongest snowfall declines roughly correspond to the region of migration of the zero degree Celsius line and emphasize the phase dependence on both altitude and latitude. Despite the modest changes in mean total precipitation, we find a consistent and statistically significant increase in the intensity of extreme winter precipitation with the multi-model mean projecting an area-averaged 12.6% increase in 20-year return period and 14.4% increase in 50-year return period daily precipitation.

Dominguez, F.

2011-12-01

48

MultiSpectral Remotely Sensed Snowfall Rate Estimation  

Microsoft Academic Search

In the last three decades, remote sensing has rapidly explored various fields of applications. One of the challenges is application of remote sensing for estimating global precipitation (rainfall\\/snowfall) particularly over regions where traditional observation technique cannot cover. In this project, satellite based multi-spectral cloud information is used for snowfall rate estimation. The developed model uses cloud-top infrared (IR) from the

Y. Mejia; S. Mahani; R. Khanbilvardi

2006-01-01

49

Recent variations of snow cover and snowfall in North America and their relation to precipitation and temperature variations  

SciTech Connect

Contemporary large-scale changes in solid and total precipitation and satellite-derived snow cover were examined over the North American continent. Annual snow cover extent over the last 19 years decreased up to 6 [times] 10[sup 5] km[sub 2] relative to a 0.93[degrees]C (0.33[degrees]C) increase in North American (Northern Hemisphere) temperature. A strong correlation exists between snow cover and temperature where up to 78% of the variance in regional snow cover and snowfall is explained by the anomalies of monthly mean maximum temperature. Over the last two decades the decrease in snow cover during winter (December-March) has largely occurred through reduced frequency of snow cover in areas that typically have a high probability of snow on the ground with little change in the frequency of snow cover in other areas. Similar characteristics were observed during spring (April-May) in areas with high snow cover probability except for an expansion of the snow-free regions. Anomalies in these two seasons dominate the interannual variability (nearly three-fourths of the variance) of snow cover. 48 refs., 15 figs., 10 tabs.

Karl, T.R.; Groisman, P.Ya.; Knight, R.W.; Heim, R.R. Jr. (National Climatic Data Center, Asheville, NC (United States))

1993-07-01

50

Snowfall induced severe pile-ups in southern Finland on 17 March 2005  

NASA Astrophysics Data System (ADS)

Weather has a great impact on road traffic and several studies have shown that accident risk increases especially during wintry weather conditions. Heavy snowfall, rain or sleet on an icy road surface and formation of hoar frost can make the driving conditions hazardous. Poor visibility, caused by snowfall or dense fog can increase the accident risk significantly and severe pile-ups on highways are possible. The risk for accidents increases, when many drivers can't adjust their speed to the worsening driving conditions even though the hazard is visible. This study presents a severe pile-up case that occurred in southern Finland near Helsinki city on Thursday 17 March 2005. Before this occasion, cold and clear weather prevailed for many days and the driving conditions were mostly fair. On 17 March a low pressure was approaching southern Finland from west. Light snowfall reached the Helsinki metropolitan area early in the morning and it was followed by a band of dense snowfall. During the rush hours, just before 0800 h, pile-ups occurred on four separate highways near Helsinki city almost at the same time (within about ten minutes). In total, almost 300 cars were crashed, 3 persons died and more than 60 persons got injured. The occurrence of dense snowfall during the rush hours had a great impact on driving conditions. The drivers heading towards Helsinki from north or northeast drove at first in clear, dry conditions, with only local light snowfall. But the sudden worsening of weather (and visibility) was a surprise for many although warnings for poor driving conditions were issued the previous evening on radio and TV. In addition to this, automatic vehicle speed measurements showed that the mean speed that morning was only a few km/h lower than on a normal day. When studying the weather situation, it appeared that near the surface there was a thin layer of cold air (2 m temperature being -5…-8 degrees) and warmer air above it. In this kind of situation super cooled water can exist in the lower troposphere, and this was also supported by dual-polarization radar observations. This fact might have had a positive impact on the slipperiness of the roads, although freezing drizzle was mainly observed only just after the passage of the dense snowfall and occurrence of the crashes. Due to low surface temperature, preventative anti-icing with salting could not be carried out early that morning (except for the western part of the area). So the snow got packed on the road surface by traffic, causing slippery conditions. In a case like this, real-time warning methods and changing speed limits could be the main way to prevent massive accidents. Dense observation network consisting of road weather observations (including visibility) and radar data should be utilized in the real-time warnings. Dense snowfall is a substantial risk for traffic on highways and severe pile-ups have occurred lately for example in Czech Republic and Austria (during March 2008).

Juga, I.; Hippi, M.

2009-09-01

51

Reduced tillage increases residue groundcover in subsequent dry pea and winter wheat crops in the Palouse region of Idaho  

Microsoft Academic Search

Crop management practices are needed that increase crop residue groundcover and reduce soil erosion after winter wheat (Triticum aestivum L. emend. Thell.) planting in the Palouse region of northern Idaho and eastern Washington. This experiment investigates if reduced tillage leaves more residue groundcover from two spring small grain crops following different tillage practices and increases crop performance in subsequent dry

Stephen O. Guy; Duncan B. Cox

2002-01-01

52

Cold temperature increases winter fruit removal rate of a bird-dispersed shrub  

Microsoft Academic Search

We tested the hypothesis that winter removal rates of fruits of wax myrtle, Myrica cerifera, are higher in colder winters. Over a 9-year period, we monitored M. cerifera fruit crops in 13 0.1-ha study plots in South Carolina, U.S.A. Peak ripeness occurred in November, whereas peak removal occurred in the coldest months, December and January. Mean time to fruit removal

Charles Kwit; Douglas J. Levey; Cathryn H. Greenberg; Scott F. Pearson; John P. McCarty; Sarah Sargent

2004-01-01

53

Development of a snowfall retrieval algorithm at high microwave frequencies  

NASA Astrophysics Data System (ADS)

A snowfall retrieval algorithm based on Bayes' theorem is developed using high-frequency microwave satellite data. In this algorithm, observational data from both airborne and surface-based radars are used to construct an a priori database of snowfall profiles. These profiles are then used as input to a forward radiative transfer model to obtain brightness temperatures at high microwave frequencies. In the radiative transfer calculations, two size distributions for snowflakes and ten observed atmospheric sounding profiles are used with snowfall profiles from observations. In addition, the scattering properties of the snowflakes are calculated on the basis of realistic nonspherical shapes using discrete dipole approximation. The algorithm is first verified by airborne microwave and radar observations and then applied to the Advanced Microwave Sounding Unit-B (AMSU-B) satellite data. The retrieved snowfall rates using AMSU-B data from three snowfall cases in the vicinity of Japan show reasonable agreement with surface radar observations with correlation coefficients of about 0.8, 0.6, and 0.96 for the three cases, respectively. The comparison results also suggest the algorithm performs better for dry and heavy snow cases, but is less accurate for wet and weak snow cases.

Noh, Yoo-Jeong; Liu, Guosheng; Seo, Eun-Kyoung; Wang, James R.; Aonashi, Kazumasa

2006-11-01

54

Elevated streamflows increase dam passage by juvenile coho salmon during winter: Implications of climate change in the Pacific Northwest  

USGS Publications Warehouse

A 4-year evaluation was conducted to determine the proportion of juvenile coho salmon Oncorhynchus kisutch passing Cowlitz Falls Dam, on the Cowlitz River, Washington, during winter. River and reservoir populations of coho salmon parr were monitored using radiotelemetry to determine if streamflow increases resulted in increased downstream movement and dam passage. This was of interest because fish that pass downstream of Cowlitz Falls Dam become landlocked in Riffe Lake and are lost to the anadromous population. Higher proportions of reservoir-released fish (0.391-0.480) passed Cowlitz Falls Dam than did river-released fish (0.037-0.119). Event-time analyses demonstrated that streamflow increases were important predictors of dam passage rates during the study. The estimated effect of increasing streamflows on the risk of dam passage varied annually and ranged from 9% to 75% for every 28.3 m3/s increase in streamflow. These results have current management implications because they demonstrate the significance of dam passage by juvenile coho salmon during winter months when juvenile fish collection facilities are typically not operating. The results also have future management implications because climate change predictions suggest that peak streamflow timing for many watersheds in the Pacific Northwest will shift from late spring and early summer to winter. Increased occurrence of intense winter flood events is also expected. Our results demonstrate that juvenile coho salmon respond readily to streamflow increases and initiate downstream movements during winter months, which could result in increased passage at dams during these periods if climate change predictions are realized in the coming decades.

Kock, Tobias J.; Liedtke, Theresa L.; Rondorf, Dennis W.; Serl, John D.; Kohn, Mike; Bumbaco, Karin A.

2012-01-01

55

GCM response of northern winter stationary waves and storm tracks to increasing amounts of carbon dioxide  

SciTech Connect

The response of the Geophysical Fluid Dynamics Laboratory (GFDL) coupled ocean-atmosphere R15, 9-level GCM to gradually increasing CO[sub 2] amounts is analyzed with emphasis on the changes in the stationary waves and storm tracks in the Northern Hemisphere wintertime troposphere. A large part of the change is described by an equivalent-barotropic stationary wave with a high over eastern Canada and a low over southern Alaska. Consistent with this, the Atlantic jet weakens near the North American coast. Perpetual winter runs of an R15, nine-level atmospheric GCM with sea surface temperature, sea ice thickness, and soil moisture values prescribed from the coupled GCM results are able to reproduce the coupled model's response qualitatively. Consistent with the weakened baroclinicity associated with the stationary wave change, the Atlantic storm track weakens with increasing CO[sub 2] concentrations while the Pacific storm track does not change in strength substantially. An R15, nine-level atmospheric model linearized about the zonal time-mean state is used to analyze the contributions to the stationary wave response. With mountains, diabatic heating, and transient forcings the linear model gives a stationary wave change in qualitative agreement with the change seen in the coupled and perpetual models. Transients and diabatic heating appear to be the major forcing terms, while changes in zonal-mean basic state and topographic forcing play only a small role. A substantial part of the diabatic response is due to changes in tropical latent heating. 25 refs., 36 figs.

Stephenson, D.B.; Held, I.M. (Princeton Univ., NJ (United States))

1993-10-01

56

Summer warming and increased winter snow cover affect Sphagnum fuscum growth, structure and production in a sub-arctic bog  

Microsoft Academic Search

Sphagnum mosses form a major component of northern peatlands, which are expected to experience substantially higher increases in temperature and winter precipitation than the global average. Sphagnum may play an important role in the responses of the global carbon cycle to climate change. We investigated the responses of summer length growth, carpet structure and production in Sphagnum fuscum to experimentally

R IEN AERTS; J OH; TERRY V. CALLAGHAN; R ICHARD S. P. VAN L OGTESTIJN

2003-01-01

57

Dissolved organic matter composition of winter flow in the Yukon River basin: Implications of permafrost thaw and increased groundwater discharge  

NASA Astrophysics Data System (ADS)

Groundwater discharge to rivers has increased in recent decades across the circumpolar region and has been attributed to thawing permafrost in arctic and subarctic watersheds. Permafrost-driven changes in groundwater discharge will alter the flux of dissolved organic carbon (DOC) in rivers, yet little is known about the chemical composition and reactivity of dissolved organic matter (DOM) of groundwater in permafrost settings. Here, we characterize DOM composition of winter flow in 60 rivers and streams of the Yukon River basin to evaluate the biogeochemical consequences of enhanced groundwater discharge associated with permafrost thaw. DOC concentration of winter flow averaged 3.9 ± 0.5 mg C L-1, yet was highly variable across basins (ranging from <1 to >20 mg C L-1). In comparison to the summer-autumn period, DOM composition of winter flow had lower aromaticity (as indicated by specific ultraviolet absorbance at 254 nm, or SUVA254), lower hydrophobic acid content, and a higher proportion of hydrophilic compounds (HPI). Fluorescence spectroscopy and parallel factor analysis indicated enrichment of protein-like fluorophores in some, but not all, winter flow samples. The ratio of DOC to dissolved organic nitrogen, an indicator of DOM biodegradability, was positively correlated with SUVA254 and negatively correlated with the percentage of protein-like compounds. Using a simple two-pool mixing model, we evaluate possible changes in DOM during the summer-autumn period across a range of conditions reflecting possible increases in groundwater discharge. Across three watersheds, we consistently observed decreases in DOC concentration and SUVA254 and increases in HPI with increasing groundwater discharge. Spatial patterns in DOM composition of winter flow appear to reflect differences in the relative contributions of groundwater from suprapermafrost and subpermafrost aquifers across watersheds. Our findings call for more explicit consideration of DOC loss and stabilization pathways associated with changing subsurface hydrology in watersheds underlain by thawing permafrost.

O'Donnell, Jonathan A.; Aiken, George R.; Walvoord, Michelle A.; Butler, Kenna D.

2012-12-01

58

Variability and trends of total precipitation and snowfall over the United States and Canada  

Microsoft Academic Search

The biases and large-scale inhomogeneities in the time series of measured precipitation and snowfall over the United States and Canada are discussed and analyzed. The spatial statistical characteristics of monthly and annual snowfall and total precipitation are investigated and parameterized. After adjustments and selection of the best' network, reliable first guess' estimates of North American snowfall and precipitation are obtained.

Pavel Ya Groisman; David R. Easterling

1994-01-01

59

Iron-Superoxide Dismutase Expression in Transgenic Alfalfa Increases Winter Survival without a Detectable Increase in Photosynthetic Oxidative Stress Tolerance1  

PubMed Central

To determine whether overexpression of Fe-superoxide (SOD) dismutase would increase superoxide-scavenging capacity and thereby improve the winter survival of transgenic alfalfa (Medicago sativa L.) plants, two genotypes were transformed with the vector pEXSOD10, which contains a cDNA for Arabidopsis Fe-SOD with a chloroplast transit peptide and cauliflower mosaic virus 35S promoter. A novel Fe-SOD was detected by native PAGE in both greenhouse- and field-grown transgenic plants, but activity varied among independent transgenic plants. The increased Fe-SOD activity was associated with increased winter survival over 2 years in field trials, but not with oxidative stress tolerance as measured by resistance of leaves to methyl viologen, a superoxide generator. Total shoot dry matter production over 2 harvest years was not associated with Fe-SOD activity. There was no detectable difference in the pattern of primary freezing injury, as shown by vital staining, nor was there additional accumulation of carbohydrates in field-acclimated roots of the transgenic alfalfa plants. We did not detect any difference in growth of one transgenic plant with high Fe-SOD activity compared with a non-transgenic control. Therefore, the improvement in winter survival did not appear to be a consequence of improved oxidative stress tolerance associated with photosynthesis, nor was it a consequence of a change in primary freezing injury. We suggest that Fe-SOD overexpression reduced secondary injury symptoms and thereby enhanced recovery from stresses experienced during winter.

McKersie, Bryan D.; Murnaghan, Julia; Jones, Kim S.; Bowley, Stephen R.

2000-01-01

60

Physical Model to Determine Snowfall over Land by Microwave Radiometry.  

National Technical Information Service (NTIS)

This paper presents one of the first algorithms to estimate snow rate over land. This algorithm is unique with respect to the two other early empirical snowfall algorithms in that it is physically-based and relates hydrometeor properties to satellite-base...

G. Skofronick-Jackson M. J. Kim

2003-01-01

61

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.

62

Total Ozone Mapping Spectrometer (TOMS) observations of increases in Asian aerosol in winter from 1979 to 2000  

SciTech Connect

Emission inventories indicate that the largest increases in SO{sub 2} emissions have occurred in Asia during the last 20 years. By inference, largest increases in aerosol, produced primarily by the conversion of SO{sub 2} to sulfate, should have occurred in Asia during the same time period. Decadal changes in regional aerosol optical depths are calculated by analyzing Total Ozone Mapping Spectrometer (TOMS) vertical aerosol optical depths (converted to 550 nm) from 1979 to 2000 on a 1{sup o} by 1{sup o} global grid. The anthropogenic component of the TOMS aerosol record is maximized by examining the seasonal cycles of desert dust and Boreal fire smoke, and identifying the months of the year for which the desert dust and Boreal fire smoke are least conspicuous. Gobi and Taklimakan desert dust in Asia is prevalent in the TOMS record during spring, and eastern Siberian smoke from Boreal forest fires is prevalent during summer. Aerosol trends are calculated on a regional basis during winter (November-February) to maximize the anthropogenic component of the aerosol record. Large increases in aerosol optical depths between 1979 and 2000 are present over the China coastal plain and the Ganges river basin in India. Aerosol increased by 17% per decade during winter over the China coastal plain, while SO{sub 2} emissions over the same geographical region increased by 33% per decade.

Massie, Steven T.; Torres, O.; Smith, Steven J.

2004-12-01

63

Potential role of winter rainfall in explaining increased moisture in the Mediterranean and Middle East during periods of maximum orbitally-forced insolation seasonality  

NASA Astrophysics Data System (ADS)

Precession-related forcing of seasonal insolation changes in the northern hemisphere (NH) alternates between maximum NH seasonality (summer perihelion-increased insolation; winter aphelion-decreased insolation) and minimum NH seasonality (summer aphelion, and winter perihelion). With maximum NH seasonality, climate models simulate stronger NH summer monsoons that bring increased precipitation to North Africa and South and East Asia, in agreement with the in-phase relation of precipitation and NH summer insolation found in many paleoclimatic records. However paleoclimatic records in parts of the Mediterranean, the Middle East, and the interior of Asia also indicate increased moisture at times of maximum NH seasonality, a change not always clearly linked to stronger summer monsoons—either because these regions are at or beyond the boundaries of the present-day monsoon or because the observations allow multiple causal interpretations, or both. This study focuses on the possible role of changes in NH winter climate in explaining these wetter episodes. Using climate model simulations, we show that the `NH winter aphelion-decreased NH winter insolation' orbital configuration is linked to the Mediterranean storm track and increased winter rains in the Mediterranean, the Middle East, and interior Asia. We conclude that wetter periods at precession time scales in these particular regions may have resulted either from increased wintertime storm track precipitation, or from a combination of increased winter and summer rainfall. Given this seasonal ambiguity, both possibilities need to be considered.

Kutzbach, J. E.; Chen, G.; Cheng, H.; Edwards, R. L.; Liu, Z.

2013-03-01

64

Coupled Model Simulation of Snowfall Events over the Black Hills.  

NASA Astrophysics Data System (ADS)

Numerical simulations of two snowfall events over the Black Hills of South Dakota are made to demonstrate the use and potential of a coupled atmospheric and land surface model. The Coupled Atmospheric-Hydrologic Model System was used to simulate a moderate topographic snowfall event of 10-11 April 1999 and a blizzard event of 18-23 April 2000. These two cases were chosen to provide a contrast of snowfall amounts, locations, and storm dynamics. The model configuration utilized a nested grid with an outer grid of 16-km spacing driven by numerical forecast model data and an inner grid of 4 km centered over the Black Hills region. Simulations for the first case were made with the atmospheric model, the Advanced Regional Prediction System (ARPS) alone, and with ARPS coupled with the National Center for Atmospheric Research Land Surface Model (LSM). Results indicated that the main features of the precipitation pattern were captured by ARPS alone. However, precipitation amounts were greatly overpredicted. ARPS coupled with LSM produced a very similar precipitation pattern, but with precipitation amounts much closer to those observed. The coupled model also permits simulation of the resulting snow cover and snowmelt. Simulated percentage snow melting occurred somewhat more rapidly than that of the observed. Snow-rain discrimination may be taken from the precipitation type falling out of the atmospheric model based on the microphysical parameterization, or by the use of a surface temperature criteria, as used in most large-scale models. The resulting snow accumulation patterns and amounts were nearly identical. The coupled model configuration was used to simulate the second case. In this case the simulated precipitation and snow depth maximum over the eastern Black Hills were biased to the east and north by about 24 km. The resulting spatial correlation of the simulated snowfall and observations was only 0.37. If this bias is removed, the shifted pattern over the Black Hills region has a correlation of 0.68. Snow-melting patterns for 21 and 22 April appeared reasonable, given the spatial bias in the snowfall simulation.

Wang, J.; Hjelmfelt, M. R.; Capehart, W. J.; Farley, R. D.

2003-06-01

65

Nutrition for winter sports  

Microsoft Academic Search

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

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

2011-01-01

66

Effect of Reduced Winter Precipitation and Increased Temperature on Watershed Solute Flux, 1988–2002, Northern Michigan  

Microsoft Academic Search

Since 1987 we have studied weekly change in winter (December–April) precipitation, snowpack, snowmelt, soil water, and stream\\u000a water solute flux in a small (176-ha) Northern Michigan watershed vegetated by 65–85 year-old northern hardwoods. Our primary\\u000a study objective was to quantify the effect of change in winter temperature and precipitation on watershed hydrology and solute\\u000a flux. During the study winter runoff was

R. Stottlemyer; D. Toczydlowski

2006-01-01

67

INCIDENCE OF PLAGUE ASSOCIATED WITH INCREASED WINTER-SPRING PRECIPITATION IN NEW MEXICO  

Microsoft Academic Search

Plague occurs episodically in many parts of the world, and some outbreaks appear to be related to increased abundance of rodents and other mammals that serve as hosts for vector fleas. Climate dynamics may influence the abundance of both fleas and mammals, thereby having an indirect effect on human plague incidence. An understanding of the relationship between climate and plague

ROBERT R. PARMENTER; EKTA PRATAP YADAV; CHERYL A. PARMENTER; PAUL ETTESTAD; KENNETH L. GAGE

68

On the characteristics of atmospheric circulation associated with snowfall in NW Greece  

Microsoft Academic Search

In this work the main atmospheric circulation types, associated with snowfall events in NW Greece, are examined. Also, a validation procedure is followed in order to investigate to what extent the circulation types revealed are related with snowfall in NW Greece. For this purpose, two datasets are used. The first one consists of 6-hourly values of mean sea level pressure,

E. E. Houssos; C. J. Lolis; A. Bartzokas

2009-01-01

69

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

70

Body mass loss during adaptation to short winter-like days increases food foraging, but not food hoarding.  

PubMed

Siberian hamsters markedly reduce their body/lipid mass ( approximately 20-45%) in short 'winter-like' days (SD). Decreases in body/lipid mass associated with food deprivation or lipectomy result in increases in foraging and food hoarding. When at their SD-induced body/lipid mass nadir, food hoarding is not increased despite their decreases in body/lipid mass, but hoarding was not tested during the dynamic period of body/lipid mass loss (first 5-6 weeks of SDs). Therefore, we tested for changes in foraging/hoarding during this initial period in Siberian hamsters housed in a simulated burrow with a wheel running-based foraging system and exposed to either long 'summer-like' days (LD) or SDs. Two foraging effort conditions were used: 10 Revolutions/Pellet (pellet delivered after running 10 revolutions) and a Free Wheel/Free Food condition (wheel available, food pellets non-contingently available). Regardless of the foraging condition, body mass was significantly reduced across 8 weeks of SDs ( approximately 15%). Foraging increased after 7 weeks in SDs, but food hoarding did not increase compared to LDs. Instead food hoarding significantly decreased in SDs at Weeks 2-5 compared with Week 0 values, with the 10 Revolutions/Pellet foraging group returning to LD levels thereafter and the Free Wheel/Free Food group remaining reduced from Weeks 2-7. Collectively, we found that SDs decreased body mass, increased foraging after 7 weeks, and increased food hoarding, but only after an initial decrease and not above that seen in LDs. These data suggest that SD-induced body/lipid mass losses do not engender similar behavioral responses as seen with food deprivation or lipectomy. PMID:19224707

Teubner, Brett J W; Bartness, Timothy J

2009-02-15

71

Annual CO2 Flux in Dry and Moist Arctic Tundra: Field Responses to Increases in Summer Temperatures and Winter Snow Depth  

Microsoft Academic Search

We examined the annual exchange of CO2 between the atmosphere and moist tussock and dry heath tundra ecosystems (which together account for over one-third of the low arctic land area) under ambient field conditions and under increased winter snow deposition, increased summer temperatures, or both. Our results indicate that these two arctic tundra ecosystems were net annual sources of CO2

J. M. Welker; J. T. Fahnestock; M. H. Jones

2000-01-01

72

The Mobility and Safety Impacts of Winter Storm Events in a Freeway Environment  

Microsoft Academic Search

This paper describes how data from several Iowa information management systems were used to analyze the mobility and safety impacts of winter storm events. Roadway and weather data were acquired from the roadway weather information system (RWIS), hourly traffic volumes from automatic traffic recorders (ATRs), and crash information from the accident location and analysis system (ALAS). Daily snowfalls were acquired

KEITH K. KNAPP; LELAND D. SMITHSON; AEMAL J. KHATTAK

73

The relationship between winter lake cover, radiation receipts and the oxygen deficit in temperate lakes  

Microsoft Academic Search

The composition, timing and duration of winter lake cover are shown to produce significant spatial and temporal variations in the radiation received at the surface of the water column, and are linked to the timing and rate of oxygen depletion of a temperate lake. In particular, the first snowfall to accumulate on the ice cover reduces radiation input to nearly

Terry D. Prowse; Robert L. Stephenson

1986-01-01

74

Major Winter Snow Storm Development: A Comparison of Two Case Studies.  

National Technical Information Service (NTIS)

The Storm of the Century is a prime example of a major East Coast winter storm. This storm devastated the East Coast from 12-15 March 1993, dumping record amounts of snowfall as well as setting record low pressure readings all along the coast. In addition...

B. L. Artery

1995-01-01

75

Exploring Alternative Parameterizations for Snowfall with Validation from Satellite and Terrestrial Radars  

NASA Astrophysics Data System (ADS)

Increases in computational resources have allowed operational forecast centers to pursue experimental, high resolution simulations that resolve the microphysical characteristics of clouds and precipitation. These experiments are motivated by a desire to improve the representation of weather and climate, but will also benefit current and future satellite campaigns, which often use forecast model output to guide the retrieval process. The combination of reliable cloud microphysics and radar reflectivity may constrain radiative transfer models used in satellite simulators during future missions, including EarthCARE and the NASA Global Precipitation Measurement. Aircraft, surface and radar data from the Canadian CloudSat/CALIPSO Validation Project are used to check the validity of size distribution and density characteristics for snowfall simulated by the NASA Goddard six-class, single-moment bulk water microphysics scheme, currently available within the Weather Research and Forecast (WRF) Model. Widespread snowfall developed across the region on January 22, 2007, forced by the passing of a midlatitude cyclone, and was observed by the dual-polarimetric, C-band radar King City, Ontario, as well as the NASA 94 GHz CloudSat Cloud Profiling Radar. Combined, these data sets provide key metrics for validating model output: estimates of size distribution parameters fit to the inverse-exponential equations prescribed within the model, bulk density and crystal habit characteristics sampled by the aircraft, and representation of size characteristics as inferred by the radar reflectivity at C- and W-band. Specified constants for distribution intercept and density differ significantly from observations throughout much of the cloud depth. Alternate parameterizations are explored, using column-integrated values of vapor excess to avoid problems encountered with temperature-based parameterizations in an environment where inversions and isothermal layers are present. Simulation of CloudSat reflectivity is performed by adopting the discrete-dipole parameterizations and databases provided in literature, and demonstrate an improved capability in simulating radar reflectivity at W-band versus Mie scattering assumptions.

Molthan, A.; Petersen, W. A.; Case, J.; Dembek, S.

2009-12-01

76

Increasing influence of ENSO and decreasing influence of AO/NAO in the recent decades over northwest India winter precipitation  

NASA Astrophysics Data System (ADS)

The interannual variability of northwest India winter precipitation (NWIWP) is examined in association with the variability of surface temperature, mean sea level pressure, tropospheric geopotential height, and wind patterns over the globe to study the changes in the large-scale circulation features associated with NWIWP. The data for the study have been considered from 1950 to 2008 (for a period of 59 years). The analysis is based on correlations and composites performed using India Meteorological Department records based on station data. We find that the interannual variability of NWIWP is influenced by Arctic Oscillation/North Atlantic Oscillation (AO/NAO) and El Niño-Southern Oscillation (ENSO) phenomena. Above-normal NWIWP is associated with the positive phase of AO/NAO and the warm phase of ENSO, but showing strong secular variations. During the recent decades, the influence of ENSO over NWIWP has increased while the influence of AO/NAO has decreased. This conclusion is supported by a consistency across the different observation data sets employed in the study. A physical mechanism for such effect is proposed, by which western disturbances are intensified over NW India by the intensification of Asian westerly jet stream over Middle East during positive phase of AO/NAO and shift and intensification of Asian jet to the lower latitudes during the warm phase of ENSO.

Yadav, R. K.; Rupa Kumar, K.; Rajeevan, M.

2009-06-01

77

Damage and compensatory effects of winter drought on winter wheat  

Microsoft Academic Search

Field experiments were carried out to investigate the damage and compensatory effects of winter drought on winter wheat. The results of the study show that, after winter drought, the growth and development of winter wheat, display obviously dual effects of damage and compensatory. The productive tiller percentage increases while spike number per hectare reduces. Plant height does not change significantly,

Xiu-Shan Tan; Bao-Xing Ye; Jian-Jie Bi

2011-01-01

78

Early stage de-etiolation increases the ferulic acid content in winter triticale seedlings under full sunlight conditions  

Microsoft Academic Search

In the presented work an attempt has been made to estimate the phenolics content and its implication for the protection of the photosynthetic apparatus in course of a plant’s de-etiolation. The experiments were carried out on two genotypes of winter triticale varying in their resistance to drought. The activity of the photosynthetic apparatus was monitored by taking measurements of chlorophyll

Tomasz Hura; Katarzyna Hura; Maciej Grzesiak

2010-01-01

79

Increasing the interval between winter outdoor exercise aggravates agonistic interactions in Hérens cows kept in tie-stalls  

Microsoft Academic Search

Cows of the dual-purpose Hérens breed are highly motivated to engage in dominance interactions and thus famous for the cow fights traditionally organised by Swiss breeders. However, this characteristic may result in excessively aggressive behaviour when cows kept in tie-stalls meet during winter outdoor exercise. This can be dangerous for both animals and breeders in terms of likelihood of injury.

Isabelle M. L. Castro; Lorenz Gygax; Beat Wechsler; Rudolf Hauser

2011-01-01

80

THE INFLUENCE ON EMERGENCY VEHICLE CAUSED BY THE GUERRILLA HEAVY SNOWFALL AND CONSIDERATION ABOUT MEASURES  

NASA Astrophysics Data System (ADS)

In Nanao City, Ishikawa, it was a sudden snowfall (the following, "guerrilla heavy snowfall") in a short time in January, 2009, and a traffic jam occurred in the various places in city. Therefore, the snow removing was late, and the emergency transportation was late, too. So, Ishikawa Prefecture performed the review of the snow removing system with this guerrilla heavy snowfall as a lesson in the next year. As a result, in January, 2011, similar guerrilla heavy snowfall was generated, but the traffic jam in the city didn't occur that much, and the big hindrance didn't produce the delay of the emergency transportation either. Therefore, in this study, I analyzed the snowfall situation of the year before and after the snow removing system improvement, the traffic jam situation and snow removing dispatch data and compared the difference quantitatively. In addition, after guerrilla heavy snowfall, the study meeting the study meeting was held by prefecture, country, city, town and association of construction industry, and they built the area snow removing cooperation system, so I carried out an interview investigation about the real enforcement situation and progress.

Takahashi, Masanori; Takayama, Jun-Ichi; Nakayama, Shoichiro

81

Supercooled Liquid Water Clouds in Utah Winter Mountain Storms: Cloud-seeding Implications of a Remote-Sensing Dataset.  

NASA Astrophysics Data System (ADS)

A polarization lidar, dual-wavelength microwave radiometer, and radiosonde dataset from 19 winter storms studied over the Tushar Mountains in the 1985 and 1987 Utah NOAA cooperative weather modification field campaigns are used to characterize embedded supercooled liquid water (SLW) clouds. The findings show the dominance of barrier-level. mildly supercooled (0° to 10°C) orographic clouds, as identified by the lidar from a midbarrier field site. The combined lidar and radiometer (with liquid water depths greater than or equal to 0.05 mm) data sample indicates an SLW cloud frequency of occurrence of about 73% of the time the lidar was operating, although only 51% of the lidar shots detected SLW clouds because of the frequent presence of range-limiting attenuation from snowfall. A significant development from this study is the application of a new autonomous computer algorithm for identifying SLW clouds store single normalized lidar shots, using only the height derivative of the returned signal and the minimum linear depolarization ratio. In terms of operational AgI cloud-seeding practices, we conclude that it is mainly the upper portions of SLW clouds with relatively warm cloud-base temperatures ( 7°C) that display potential for yielding increased snowfall, since only these clouds regularly produced significant (0.15 mm) radiometric liquid water depths.

Sassen, Kenneth; Zhao, Hongjie

1993-09-01

82

A new look at lake-effect snowfall trends in the Laurentian Great Lakes using a temporally homogeneous data set  

Microsoft Academic Search

Snowfall data are subject to quality issues that affect their usefulness for detection of climate trends. A new analysis of lake-effect snowfall trends utilizes a restricted set of stations identified as suitable for trends analysis based on a careful quality assessment of long-term observation stations in the lake-effect snowbelts of the Laurentian Great Lakes. An upward trend in snowfall was

Kenneth E. Kunkel; Leslie Ensor; Michael Palecki; David Easterling; David Robinson; Kenneth G. Hubbard; Kelly Redmond

2009-01-01

83

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 teachers 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

84

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

85

Winter Forest Processes: Measurements and Modeling  

NASA Astrophysics Data System (ADS)

Winter-forest processes affect global and local climates.Weather-forecast, climate and hydrological modelers incorporate increasingly realistic surface schemes into their models, and algorithms describing snow accumulation and snow-interception sublimation are now finding their way into these schemes. Both point and spatially variable data for calibration and verification of wintertime dynamics are therefore needed for such modeling schemes. Snow forest atmosphere interaction studies at Luleå University of Technology (in co-operation with researchers in Sweden, Finland, UK and Japan) show that seasonal sublimation fraction of snow precipitation in confined coniferous forests range about 0.35 and single events with sublimation rates of up to 3.9 mm in 7 h were observed. The most important factors for calculating the sublimation were: the relative humidity, the aerodynamic resistance, the wind speed and the intercepted mass. The techniques used to study processes and rates were weighing cut tree and weighing througfall (in Sweden) ?-ray attenuation and tree weighing systems, combined with plastic sheet net rainfall gauges for throughfall (in UK) and snow course measurements in combination with forest density measurements (in Finland) and with sky view fraction (SVF) measurements (fish eyed camera)(in Japan). For the last study forest snow accumulation (SF) could be estimated from snowfall in open fields (SO) and from SVF according to: SF = SO (0.56 + 0.6 × SVF) for SVF < 0.72 and SF = SO for SVF > 0.72 (R2 = 0.86) as well as from leaf area index (LAI). For observation plots exceeding 1 ha the SVF was correlated to the normalized difference snow index (NDSI) using a Landsat-TM image and SF was related to SO and NDSI according to SF = SO (0.81 - 0.37 × NDSI). Plot-size limitations allowed inclusion of only one sparse forest observation so the relationship is somewhat hypothetical and further studies are required to confirm it.

Angela, L.

2006-12-01

86

Litter decomposition and soil respiration in response to increased rainfall variability, winter warming and altered cutting frequency in a temperate grassland  

NASA Astrophysics Data System (ADS)

Climate change is likely to alter decomposition rates through direct effects on soil biotic activity and indirect effects on litter quality with possible impacts on the global carbon budget and nutrient cycling. Currently, there is an urgent need to study combined effects of various climatic drivers and of agricultural practise on decomposition. In an in-situ litter bag experiment, we studied effects of rainfall variability (including drought plus heavy rain pulses and regular irrigation) interacting with winter warming and increased winter precipitation and with changes in cutting frequency, on decomposition in a temperate grassland. Litter bags contained mixed and species-specific litter out of all different climate and land-use manipulations and were placed within the plots of litter origin. Moreover, we aimed to disentangle causes for altered decomposition by following two further approaches: To study effects of changed leaf chemicals due to the manipulations we placed litter out of the experiment that has been pre-exposed to the manipulations before on an untreated standard plot outside the experiment. To assess effects of changed soil faunal activity, we investigated decomposition of standard material under differing rainfall variability. We further compare the observed decomposition results with soil respiration data. Decomposition was reduced when litter bags were exposed to drought for six weeks within an 11 months period. Neither additional winter rain nor winter warming had an effect on decomposition, probably because winter warming reduced snow cover and increased variability of surface temperatures. Climate manipulations did not change litter quality. Further, decomposition on the untreated standard plot was not affected by the climate manipulations that the litter previously was exposed to. Thus, reduced decomposition under extreme rainfall variability and drought may be mainly caused by a decrease in soil biotic activity, as indicated by reduced decomposition of standard material during drought. More frequent cutting strongly stimulated decomposition, however, this stimulating effect was absent under extreme rainfall variability including drought. The stimulation of decomposition under more frequent cutting was attributed to changes in litter quality, namely a decrease in C/N ratio. Accordingly, litter from more frequently cut communities decomposed faster on the untreated control plot outside the experiment. Projected increases in drought frequency and increased rainfall variability under climate change may inhibit decomposition and alter nutrient and carbon cycling along with soil quality. Especially decomposition in frequently cut grassland appears vulnerable towards drought.

Kreyling, Juergen; Walter, Julia; Grant, Kerstin; Beierkuhnlein, Carl; Jentsch, Anke

2013-04-01

87

The Value of Snowfall to Skiers and Boarders  

Microsoft Academic Search

An interesting winter sport phenomenon inrecent years has been the growth ofsnowboarding. Snowboarding has outpaced skiingat many resorts and has become the snow ridingactivity of choice for many young people. Thisstudy develops an empirical demand model forwinter sport trips amongst college studentsfrom both camps and estimates economic welfareassociated with the two different activities. The results show that both trip demand

Jeffrey Englin; Klaus Moeltner

2004-01-01

88

Why Does Rhinopithecus bieti Prefer the Highest Elevation Range in Winter? A Test of the Sunshine Hypothesis  

PubMed Central

Environmental factors that affect spatiotemporal distribution patterns of animals usually include resource availability, temperature, and the risk of predation. However, they do not explain the counterintuitive preference of high elevation range in winter by the black-and-white snub-nosed monkey (Rhinopithecus bieti). We asked whether variation of sunshine along with elevations is the key driving force. To test this hypothesis, we conducted field surveys to demonstrate that there was a statistically significant pattern of high elevation use during winter. We then asked whether this pattern can be explained by certain environmental factors, namely temperature, sunshine duration and solar radiation. Finally, we concluded with a possible ecological mechanism for this pattern. In this study, we employed GIS technology to quantify solar radiation and sunshine duration across the monkey's range. Our results showed that: 1) R. bieti used the high altitude range between 4100–4400 m in winter although the yearly home range spanned from 3500–4500 m; 2) both solar radiation and sunshine duration increased with elevation while temperature decreased with elevation; 3) within the winter range, the use of range was significantly correlated with solar radiation and sunshine duration; 4) monkeys moved to the areas with high solar radiation and duration following a snowfall, where the snow melts faster and food is exposed earlier. We concluded that sunshine was the main factor that influences selection of high elevation habitat for R. bieti in winter. Since some other endotherms in the area exhibit similar winter distributional patterns, we developed a sunshine hypothesis to explain this phenomenon. In addition, our work also represented a new method of integrating GIS models into traditional field ecology research to study spatiotemporal distribution pattern of wildlife. We suggest that further theoretical and empirical studies are necessary for better understanding of sunshine influence on wildlife range use.

Behm, Jocelyn E.; Wang, Lin; Huang, Yong; Long, Yongcheng; Zhu, Jianguo

2011-01-01

89

Winter Festival.  

ERIC Educational Resources Information Center

This is one of a series of elementary readers written in Cantonese and English and designed to familiarize children with the traditional major Chinese festivals celebrated by the Chinese in America. This booklet describes the occasion for the Winter Festival (the beginning of winter) and follows a Chinese-American family in its preparation for and…

Lew, Gordon

90

Winter Festival.  

ERIC Educational Resources Information Center

|This is one of a series of elementary readers written in Cantonese and English and designed to familiarize children with the traditional major Chinese festivals celebrated by the Chinese in America. This booklet describes the occasion for the Winter Festival (the beginning of winter) and follows a Chinese-American family in its preparation for…

Lew, Gordon

91

Estimation of snow microphysical properties with application to millimeter-wavelength radar retrievals for snowfall rate  

NASA Astrophysics Data System (ADS)

The need for measuring snowfall is driven by the roles snow plays providing freshwater resources and affecting climate. Snow accumulations are an important resource for ecological and human needs and in many areas appear vulnerable to climate change. Snow cover modifies surface heat fluxes over areas extensive enough to influence climate at regional and perhaps global scales. Seasonal runoff from snowmelt, along with over-ocean snowfall, contributes to freshening in the Arctic and high-latitude North Atlantic oceans. Yet much of the Earth's area for which snowfall plays such significant roles is not well-monitored by observations. Radar reflectivity at 94 GHz is sensitive to scattering by snow particles and CloudSat, in a near-polar orbit, provides vertically resolved measurements of 94 GHz reflectivity at latitudes from 82 N to 82 S. While not global in areal coverage, CloudSat does provide observations sampled from regions where snowfall is the dominant form of precipitation and an important component of hydrologic processes. The work presented in this study seeks to exploit these observations by developing and assessing a physically-base snowfall retrieval which uses an explicit representation of snow microphysical properties. As the reflectivity-based snowfall retrieval problem is significantly underconstrained, a priori information about snow microphysical properties is required. The approaches typically used to develop relations between reflectivity and snowfall rate, so-called Ze-S relations, require assumptions about particle properties such as mass, area, fallspeed, and shape. Limited information about the distributions of these properties makes difficult the characterization of how uncertainties in the properties influence uncertainties in the Ze-S relations. To address this, the study proceeded in two parts. In the first, probability distributions for snow particle microphysical properties were assessed using optimal estimation applied to multi-sensor surface-based snow observations from a field campaign. Mass properties were moderately well determined by the observations, the area properties less so. The retrieval revealed nontrivial correlations between mass and area parameters not apparent in prior studies. Synthetic testing showed that the performance of the retrieval was hampered by uncertainties in the fallspeed forward model. The mass and area properties obtained from this retrieval were used to construct particle models including 94 GHz scattering properties for dry snow. These properties were insufficient to constrain scattering properties to match observed 94 GHz reflectivities. Vertical aspect ratio supplied a sufficient additional constraint. In the second part, the CloudSat retrieval, designed to estimate vertical profiles of snow size distribution parameters from reflectivity profiles, was applied to measurements from the field campaign and from an orbit of CloudSat observations. Uncertainties in the mass and area microphysical properties, obtained from the first part of this study, were substantial contributors to the uncertainties in the retrieved snowfall rates. Snowfall rate fractional uncertainties were typically 140% to 200%. Accumulations of snowfall calculated from the retrieval results matched observed accumulations to within 13%, however, when allowances were made for snowfall with properties likely inconsistent with the snow particle model. Information content metrics showed that the size distribution slope parameters were moderately to strongly constrained by the reflectivity observations, while the intercept parameters were determined primarily by the a priori constraints. Results from the CloudSat orbit demonstrated the ability of the CloudSat retrieval to represent a range of scene-dependent Ze-S relations.

Wood, Norman Bryce

92

Weather Support to Deicing Decision Making (WSDDM): A Winter Weather Nowcasting System.  

NASA Astrophysics Data System (ADS)

This paper describes a winter weather nowcasting system called Weather Support to Deicing Decision Making (WSDDM), designed to provide airline, airport, and air traffic users with winter weather information relevant to their operations. The information is provided on an easy to use graphical display and characterizes airport icing conditions for nonmeteorologists. The system has been developed and refined over a series of winter-long airport demonstrations at Denver's Stapleton International Airport, Chicago's O'Hare International Airport, and New York's LaGuardia Airport. The WSDDM system utilizes commercially available weather information in the form of Next Generation Weather Radar WSR-88D radar reflectivity data depicted as color coded images on a window of the display and Aviation Routine Weather Report (METAR) surface weather reports from Automated Surface Observating System stations and observers. METAR information includes wind speed and direction, air temperature, and precipitation type/rate, which are routinely updated on an hourly basis or more frequently if conditions are changing. Recent studies have shown that the liquid equivalent snowfall rate is the most important factor in determining the holdover time of a deicing fluid. However, the current operational snowfall intensity reported in METARs is based on visibility, which has been shown to give misleading information on liquid equivalent rates in many cases due to the wide variation in density and shape of snow. The particular hazard has been identified as high visibility-high snowfall conditions. The WSDDM system addresses this potentially hazardous condition through the deployment of snow gauges at an airport. These snow gauges report real-time estimates of the liquid equivalent snowfall rate once every minute to WSDDM users. The WSDDM system also provides 30-min nowcasts of liquid equivalent snowfall rate through the use of a real-time calibration of radar reflectivity and snow gauge snowfall rate. This paper discusses the development of the system, including the development of new wind shields for snow gauges to improve catch efficiency, as well as the development of the above mentioned real-time method to convert radar reflectivity to snowfall rate on the ground using snow gauges. In addition, we discuss results from a user evaluation of the system, as well as results from an efficiency and safety benefits study of the system.

Rasmussen, Roy; Dixon, Mike; Hage, Frank; Cole, Jeff; Wade, Chuck; Tuttle, John; McGettigan, Starr; Carty, Thomas; Stevenson, Lloyd; Fellner, Warren; Knight, Shelly; Karplus, Eli; Rehak, Nancy

2001-04-01

93

A new snowfall detection algorithm over land using measurements from the Advanced Microwave Sounding Unit (AMSU)  

Microsoft Academic Search

This study introduces a new snowfall detection algorithm over land using AMSU measurements. The algorithm utilizes a combination of channels in the microwave window, water vapor and oxygen absorption regions. The new algorithm is combined with the current NOAA operational AMSU rain rate product for falling snow and rain areal extent retrievals over the U.S. These retrievals are compared with

Cezar Kongoli; Paul Pellegrino; Ralph R. Ferraro; Norman C. Grody; Huan Meng

2003-01-01

94

A neural netwotk based approach for multi-spectral snowfall detection and estimation  

Microsoft Academic Search

The principal intent of this research is to: (a) investigate the potential of passive microwave data from AMSU in detecting snowfall events and in measuring their intensity, and (b) evaluate the effect of both land cover and atmospheric conditions on the retrieval accuracy. Additional information such as cloud cover and air temperature were added to the process to reduce misidentified

Yajaira Mejia; Hosni Ghedira; Shayesteh Mahani; Reza Khanbilvardi

2007-01-01

95

CO 2Snowfall on Mars: Simulation with a General Circulation Model  

Microsoft Academic Search

Although CO2snowfall has never been directly observed on Mars, it has been suggested that such precipitation may explain the puzzling infrared measurements obtained by Mariner 9 and Viking during the polar night in each hemisphere. The radiative effect of the snow would strongly alter the radiative balance of the condensing polar caps and thus the CO2cycle and the global climate.

Francois Forget; Frederic Hourdin; Olivier Talagrand

1998-01-01

96

Effect of storm trajectories on snowfall chemistry in Rocky Mountain National Park, Colorado  

USGS Publications Warehouse

Snowfall samples from snowstorms lasting 1 to 4 days were collected near the Bear Lake snow telemetry (SnoTel) site in Rocky Mountain National Park, Colorado (ROMO), during the 1998-99 snowfall season to determine if storms moving in from different directions affect the chemistry of precipitation in the park. Storm pathways to Bear Lake during snowfall events were estimated using the HYSPLIT4 backward-trajectory model developed by the National Oceanic and Atmospheric Administration. Deposition of acidic ions of nitrate and sulfate in snowfall during the study varied substantially (two- to threefold) depending on storm trajectory because air masses traversing the park originated from different surrounding areas, including some having large sources of emissions of nitrate and sulfate. Concentrations of nitrate and sulfate in samples were lowest when storms reached ROMO from north and east of the park and were elevated when air masses traveled from the west where a number of power plants are located. Concentrations were highest in storms reaching ROMO from the south, a region with urban areas including Metropolitan Denver.

Ingersoll, G. P.; Tonnessen, K. A.; Campbell, D. H.; Glass, B. R.; Torizzo, A. O.

2001-01-01

97

The 8th-10 th January 2009 snowfalls: a case of Mediterranean warm advection event  

Microsoft Academic Search

From 8 th to 10 th of January 2009, significant snowfalls were reported in many areas of the Iberian Peninsula and the Balearic Islands. This relevant event was very important from the meteorological and social impact point of views. The snow affected many zones, especially the regions of Madrid, Castilla & León and Castilla-La Mancha (Spanish central plateau) with the

F. Aguado; E. Ayensa; M. Barriga; J. Del Hoyo; A. Fernández; N. Garrido; A. Martín; F. Martín; I. Martínez Roa A; R. Pascual

2009-01-01

98

A physical model to estimate snowfall over land using AMSU-B observations  

NASA Astrophysics Data System (ADS)

In this study, we present a physical model to retrieve snowfall rate over land using brightness temperature observations from NOAA's Advanced Microwave Sounder Unit-B (AMSU-B) at 89 GHz, 150 GHz, 183.3 ± 1 GHz, 183.3 ± 3 GHz, and 183.3 ± 7 GHz. The retrieval model is applied to the New England blizzard of 5 March 2001 which deposited about 75 cm of snow over much of Vermont, New Hampshire, and northern New York. In this physical model, prior retrieval assumptions about snowflake shape, particle size distributions, environmental conditions, and optimization methodology have been updated. Here, single scattering parameters for snow particles are calculated with the discrete-dipole approximation (DDA) method instead of assuming spherical shapes. Five different snow particle models are considered. Snow particle size distributions are assumed to vary with air temperature and to follow aircraft measurements described by previous studies. Brightness temperatures at AMSU-B frequencies for the New England blizzard are calculated using these DDA calculated single scattering parameters and particle size distributions. The vertical profiles of pressure, temperature, relative humidity and hydrometeors are provided by MM5 model simulations. These profiles are treated as the a priori database in the Bayesian retrieval algorithm. In algorithm applications to the blizzard data, calculated brightness temperatures associated with selected database profiles agree with AMSU-B observations to within about ±5 K at all five frequencies. Retrieved snowfall rates compare favorably with the near-concurrent National Weather Service (NWS) radar reflectivity measurements. The relationships between the NWS radar measured reflectivities Ze and retrieved snowfall rate R for a given snow particle model are derived by a histogram matching technique. All of these Ze-R relationships fall in the range of previously established Ze-R relationships for snowfall. This suggests that the current physical model developed in this study can reliably estimate the snowfall rate over land using the AMSU-B measured brightness temperatures.

Kim, Min-Jeong; Weinman, J. A.; Olson, W. S.; Chang, D.-E.; Skofronick-Jackson, G.; Wang, J. R.

2008-05-01

99

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.

Foundation, Wgbh E.

2010-12-13

100

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

101

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. 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. ...

Brieanne

2011-02-14

102

Total Ozone Mapping Spectrometer (TOMS) observations of increases in Asian aerosol in winter from 1979 to 2000  

Microsoft Academic Search

Emission inventories indicate that the largest increases in SO emissions have occurred in Asia during the last 20 years. By inference, largest increases in aerosol, produced primarily by the conversion of SO to sulfate, should have occurred in Asia during the same time period. Decadal changes in regional aerosol optical depths are calculated by analyzing Total Ozone Mapping Spectrometer (TOMS)

Steven T. Massie; Omar Torres; Steven J. Smith

2004-01-01

103

Lessons learnt from the snow emergency management of winter season 2008-2009 in Piemonte  

NASA Astrophysics Data System (ADS)

The winter season 2008-2009 has been characterized by heavy snowfalls over the western Alps. The snowfalls have been exceptional because of their earliness, persistence, intensity and territorial spread. The impact on the regional environment and territory has been relevant, also from the economical point of view, as well as the effort of the people involved in the forecasting, prevention and fighting actions. The environmental induced effects have been shown until late spring. Several snowfall events affected also the plains and the main towns, causing social impacts. The purpose of this work is to describe the overall effects of the anomalous snowfalls and the emergency response by the local government and institutions to face the hazard scenario and mitigate the risk for people, properties and environment. Arpa Piemonte (Regional Agency for Environmental Protection) gave the technical support to the snow emergency management borrowing the expertise acquired during the heavy hydrological events occurred in the Piemonte region and contributing to minimize losses. A short list of recommendations came out from the experience, as well as the technical tools and products, all highlighting the emergency preparedness relevance.

Pelosini, R.; Bovo, S.; Cordola, M.

2011-02-01

104

Correcting basin-scale snowfall in a mountainous basin using a distributed snowmelt model and remote sensing data  

NASA Astrophysics Data System (ADS)

Adequate estimation of the spatial distribution of snowfall is critical in hydrologic modeling. However, this is a well-known problem in estimating basin-scale snowfall, especially in mountainous basins with data scarcity. This study focuses on correction and estimation of this spatial distribution, which considers topographic effects within the basin. A method is proposed that optimizes an altitude-based snowfall correction factor (Cfsnow). This is done through multi-objective calibration of a spatially distributed, multilayer energy and water balance-based snowmelt model (WEB-DHM-S) with observed discharge and remotely sensed snow cover data from the Moderate Resolution Imaging Spectroradiometer (MODIS). The Shuffled Complex Evolution - University of Arizona automatic search algorithm is used to obtain the optimal value of Cfsnow for minimum cumulative error in discharge and snow cover simulations. Discharge error is quantified by Nash-Sutcliffe efficiency and relative volume deviation, and snow cover error was estimated by pixel-by-pixel analysis. The study region is the heavily snow-fed Yagisawa Basin of the Upper Tone River in northeast Japan. First, the system was applied to one snow season (2002-2003), obtaining an optimized Cfsnow of 0.0007 m-1. For validation purposes, the optimized Cfsnow was implemented to correct snowfall in 2004, 2002 and 2001. Overall, the system was effective, implying improvements in correlation of simulated vs. observed discharge and snow cover. The 4 yr mean of basin-average snowfall for the corrected spatial snowfall distribution was 1160 mm (780 mm before correction). Execution of sensitivity runs against other model input and parameters indicated that Cfsnow could be affected by uncertainty in shortwave radiation and setting of the threshold air temperature parameter. Our approach is suitable to correct snowfall and estimate its distribution in poorly-gauged basins, where elevation dependence of snowfall amount is strong.

Shrestha, M.; Wang, L.; Koike, T.; Tsutsui, H.; Xue, Y.; Hirabayashi, Y.

2013-09-01

105

Nuclear winter  

Microsoft Academic Search

The 13 speakers at the October 1983 Conference on the World After Nuclear War each contributed specialized knowledge to the climatic and biological effects of nuclear war. The author highlights the findings of the TTAPS (named for its authors) study and confirmation by Soviet scientists on the nuclear winter. Atmospheric consequences would come from debris blocking sunlight and creating conditions

Ehrlich

1984-01-01

106

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.

107

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…

Coy, Mary

2011-01-01

108

Winter's Tale  

NSDL National Science Digital Library

This resource explores winter weather and frozen precipitation. Precipitation (in the form of snow, sleet and freezing rain) is explained, as are a variety of cloud types and generation, the nature and generation of the jet stream, and the aesthetic wonders of frozen water. A bibliography is also provided.

109

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.

110

Effects of climate change on the intensity and frequency of heavy snowfall events in the Pyrenees  

Microsoft Academic Search

The intensity and frequency of heavy snowfall events in the Pyrenees were simulated using data from the HIRHAM regional climate\\u000a model for a control period (1960–1990) and two greenhouse emission scenarios (SRES B2 and A2) for the end of the twenty-first\\u000a century (2070–2100). Comparisons between future and control simulations enabled a quantification of the expected change in\\u000a the intensity and

Juan Ignacio López-Moreno; S. Goyette; S. M. Vicente-Serrano; M. Beniston

2011-01-01

111

Total lightning within electrified snowfall using LMA, NLDN and WTLN measurements  

NASA Astrophysics Data System (ADS)

Three electrified snowfall cases are examined using total lightning measurements from lightning mapping arrays (LMAs), the National Lightning Detection Network (NLDN) and the WeatherBug Total Lightning Network (WTLN). Two events are from the Mid-Atlantic region of the US, while the third is from a heavy snowfall event in the Southeast US. In each of these events, electrical activity was in conjunction with heavy snowfall rates, sometimes exceeding 5-8 cm per hour. A combination of LMA, NLDN and WTLN data indicate that many of these flashes initiated from tall communications towers and traveled over large horizontal distances, consistent with flashes in the trailing stratiform regions of mature MCSs. Sequencing of leader development and discharge episodes, and their polarities, are inferred by combining WTLN and LMA. In one extensive tower strike, alternating ground and cloud discharge components stimulated further leader development and ground strikes. During the Southeast US event, the Advanced Radar for Meteorological and Operational Research (ARMOR) C-band dual polarimetric radar was collecting range height indicators (RHIs). The combination of ARMOR dual polarimetric radar and VHF LMA observations suggested contiguous layer changes in height between sloping aggregate-dominated layers and horizontally-oriented crystals. These layers may have provided ideal conditions for the development of extensive regions of charge and resultant horizontal propagation of the lightning flashes over large distances.

Schultz, C. J.; Bruning, E. C.; Carey, L. D.; Petersen, W. A.; Heckman, S.

2011-12-01

112

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 ...

Sappa, Mr.

2010-05-26

113

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? ...

Smith, Miss

2010-09-27

114

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 ...

Liz, Miss

2010-05-26

115

Winter Operations-Abrasives and Salt Brine.  

National Technical Information Service (NTIS)

The primary objective of winter maintenance operations is to improve traffic safety and efficiency during winter storm periods. Abrasives and salt brines have been successfully applied to increase traction and prevent snow and ice from bonding to road sur...

G. Pesti Y. Liu

2003-01-01

116

Thresholds of Passive Microwave Snowfall Detection Determined Using A-Train Observations  

NASA Astrophysics Data System (ADS)

In this study we explore a database of CloudSat+AMSU-B coincident overpasses to determine the minimum threshold of passive microwave detection of snowfall using the high-frequency channels available on GMI. Using the Advanced Infrared Sounder (AIRS) temperature and water vapor profiles along with a surface emissivity database developed from AMSU-B and MHS observations, clear-sky radiances are simulated and compared to AMSU-B observed radiances for all profiles with a maximum temperature less than 271 K. The ability of a scattering signal (observed brightness tempertaure colder than clear-sky brightness temperature by a threshold T) to detect snowfall (CloudSat reflectivity greater than threshold Z) is quantified using the Heidke Skill Score. The 183+/-1 and 183+/-3 GHz channels have the highest skill scores, while those channels that are sensitive to the surface (89, 150 and 183+/-7 GHz) have zero or even negative skill (depending on Z and T), implying that an emission signal (presumably from cloud water) is as good or better for detecting precipitation than a scattering signal. These results emphasize the need for proper characterization of surface emissivity and adequate representation of cloud water in cold season precipitation profiles that form the databases used for Bayesian retrievals from GMI and other GPM constellation radiometers.

Munchak, S. J.; Skofronick Jackson, G.; Johnson, B. T.

2011-12-01

117

Observed changes in extreme winter events in Europe with implication for transport system  

NASA Astrophysics Data System (ADS)

Extreme weather events, such as heavy rain and snow events, storms, strong winds, low visibility, hail and extreme temperatures can have negative impact on transport sector, causing severe damages and large economic losses. Weather and climate extremes have been changed over the last few decades and are likely to continue to change in the future due to the projected climate change. Consequences of changes may be both negative and positive for transportation. Extreme winter conditions have implications for the mobility and safety of operations, leading to significant transport disruptions, increased accident risk and costs of damage. In the present study we provide a comprehensive climatology of extreme winter weather events over the European continent relevant to the transport system with primary focus on recent decades (1971-2000). Individual phenomena, such as heavy snowfall, freezing temperatures, strong winds and wind gust and also their combinations, blizzard, freezing rain are considered. The estimation of the recent and past severe events is based on the observed data available from the meteorological services, from the E-OBS dataset and the ERA40 re-analysis dataset. The analysis of the relevant hazardous weather phenomena takes into account the ranking and impact threshold values defined from the viewpoint of different transport modes, such as road, rail, aviation, waterways and light, and infrastructure. A range of statistical methods are applied to define the features of these extremes, such as their probability, changes in the spatial extension, intensity and temporal duration. In order to assess the changes in regional extremes and their effects, a European regionalization regarding similar impacts on transport network is performed. The results of extreme weather and climate events classification are also shown through a set of geographical maps.

Vajda, A.; Tuomenvirta, H.

2010-09-01

118

Experimental Increases in Snow Alter Physical, Chemical and Feedback Processes in the High Arctic.  

NASA Astrophysics Data System (ADS)

Winter climate conditions are changing throughout the Arctic. In Greenland, there are observed increases in snowfall across portions of the island while the margins of the Greenland Ice Sheet are thinning. However, these changes and the consequences of altered meteorological surface dynamics on High Arctic terrestrial ecosystems and their potential feedbacks are unclear. Increases in winter snow cover may cause warmer soils in winter, greater rates of winter C losses, increases in winter N mineralization, shorter growing seasons and reduced net C gain in summer due to either reduced gross photosynthesis or increases in ecosystem respiration. In our study, we have constructed replicated snow fences in prostrate dwarf shrub tundra (polar desert and semi- desert) ecosystems in NW Greenland. Our measurements were taken at the deep (1.0 m snow depth) and intermediate (0.35 m snow depth) points along the drift to address these questions: a) how do increases in snow depth alter the surface and subsurface physical and chemical processes of these ecosystems?, and b) to what extent do increases in snow depth alter net CO2 exchange, gross ecosystem photosynthesis and ecosystem respiration? After three years of treatment we have found that in winter, deep snow results in warmer soil temperatures and in the subsequent summer, areas with deep winter snow have colder soil temperatures. This effect is most pronounced immediately following snowmelt and temperatures slowly return to ambient conditions near the end of summer. Deeper snow results in higher soil water contents in early summer, but by mid-July soil water contents have returned to ambient levels. Net ecosystem CO2 exchange rates are consistently negative (CO2 source to the atmosphere) through most of the growing season and vary in their magnitude by snow depth and ecosystem type. Areas with the deepest snow during winter consistently have the largest rates of CO2 loss to the atmosphere. The middle snow depth treatment showed lower rates of respiration than the deep treatment in both ecosystem types and greater photosynthetic gains at the semi-desert site. Our study indicates that surface processes in the High Arctic are sensitive to winter snow depth and that the resultant changes in physical, chemical and biological processes alter the magnitude and patterns of feedbacks between High Arctic landscapes and the arctic atmosphere.

Rogers, M.; Welker, J.; Sullivan, P.; Sletten, R.; Arens, S.; Kristenson, H.

2007-12-01

119

Experimental Increases in Snow Alter Physical, Chemical and Feedback Processes in the High Arctic.  

NASA Astrophysics Data System (ADS)

Winter conditions are changing throughout the Arctic. There are observed increases in snowfall across portions of Greenland while the margins of the Greenland Ice Sheet are thinning. However, these changes and the consequences of altered surface dynamics on High Arctic terrestrial ecosystems and their potential feedbacks are unclear. Increases in snow may cause warmer soils in winter, greater rates of winter C losses, increases in winter N mineralization, shorter growing seasons and reduced net C gain in summer due to either reduced gross photosynthesis or increases in ecosystem respiration. In this study, we have constructed replicated snow fences in polar desert and semi-desert (prostrate dwarf shrub) ecosystems in NW Greenland. Our measurements were taken at the deep (1.0 m snow depth) and intermediate (0.35 m snow depth) points along the drift to address these questions: a) how do increases in snow depth alter the surface and subsurface physical and chemical processes of these ecosystems?, and b) to what extent do increases in snow depth alter net CO2 exchange, gross ecosystem photosynthesis and ecosystem respiration? After three years of treatment we have found that in winter, deep snow results in warmer soil temperatures and in the subsequent summer, areas with deep winter snow have colder soil temperatures. This effect is most pronounced immediately following snowmelt and temperatures slowly return to ambient conditions near the end of summer. Deeper snow results in higher soil water contents in early summer but by mid-July soil water contents are the same, regardless of previous winter snow conditions. Net ecosystem CO2 exchange rates are consistently negative (C source to the atmosphere) through most of the growing season and vary in their magnitude by snow depth and ecosystem type. Areas with the deepest snow during winter consistently have the largest losses of CO2 to the atmosphere. The middle snow depth treatment showed lower rates of respiration than the deep treatment in both ecosystem types and greater photosynthetic gains at the semi-desert site. The CO2 fluxes were smaller and less consistent at the polar desert. Our study indicates that surface processes in the High Arctic are sensitive to winter snow depth and that the resultant changes in physical, chemical and biological processes alter the magnitude and patterns of feedbacks between High Arctic landscapes and the arctic atmosphere.

Rogers, M.; Welker, J.; Arens, S.; Hagedorn, B.; Sletten, R.; Persson, K.

2006-12-01

120

Single-dose cholecalciferol suppresses the winter increase in parathyroid hormone concentrations in healthy older men and women: a randomized triaI?3  

Microsoft Academic Search

A randomized double-blind controlled trial of a single oral dose of 2.5 mg(100 000 IU) cholecalciferol (vitamin D3) was conducted in the winter in 189 healthy free-living men and women aged 63-76 y. The mean baseline serum concentra- tion for 25-hydroxyvitamin D was 34.5 nmolfL and for parathy- roid hormone 3.18 pmolIL. After 5 wk, mean serum 25-hydroxy- vitamin D

Kay-Tee Khaw; Robert Scragg; Sean Murphy

121

The economic and social disruption arising from the snowfall hazard in Scotland—The example of January 1978  

Microsoft Academic Search

Disruption to the economy is caused by snowfall according to its physical nature and the state of preparedness of the community. The blizzards in N.E. Scotland in 1978 resulted in significant disruption and high costs. A major deployment of helicopters was a feature of the measures taken to deal with the situation, but preparations to meet such conditions on the

A. H. Perry; L. Symons

1980-01-01

122

A robust neural network system ensemble approach for detecting and estimating snowfall from the advanced microwave sounding unit  

Microsoft Academic Search

The principal intent of this research is to: (a) investigate the potential of passive microwave data from AMSU in detecting snowfall events and in measuring their intensity, and (b) evaluate the effect of both land cover and atmospheric conditions on the retrieval accuracy. A neural-network-based model has been developed and has shown a great potential in detecting and estimating the

Yajaira Mejia

2008-01-01

123

Observation of snowfall with a low-power FM-CW K-band radar (Micro Rain Radar)  

NASA Astrophysics Data System (ADS)

Quantifying snowfall intensity especially under arctic conditions is a challenge because wind and snow drift deteriorate estimates obtained from both ground-based gauges and disdrometers. Ground-based remote sensing with active instruments might be a solution because they can measure well above drifting snow and do not suffer from flow distortions by the instrument. Clear disadvantages are, however, the dependency of e.g. radar returns on snow habit which might lead to similar large uncertainties. Moreover, high sensitivity radars are still far too costly to operate in a network and under harsh conditions. In this paper we compare returns from a low-cost, low-power vertically pointing FM-CW radar (Micro Rain Radar, MRR) operating at 24.1 GHz with returns from a 35.5 GHz cloud radar (MIRA36) for dry snowfall during a 6-month observation period at an Alpine station (Environmental Research Station Schneefernerhaus, UFS) at 2,650 m height above sea level. The goal was to quantify the potential and limitations of the MRR in relation to what is achievable by a cloud radar. The operational MRR procedures to derive standard radar variables like effective reflectivity factor ( Z e) or the mean Doppler velocity ( W) had to be modified for snowfall since the MRR was originally designed for rain observations. Since the radar returns from snowfall are weaker than from comparable rainfall, the behavior of the MRR close to its detection threshold has been analyzed and a method is proposed to quantify the noise level of the MRR based on clear sky observations. By converting the resulting MRR- Z e into 35.5 GHz equivalent Z e values, a remaining difference below 1 dBz with slightly higher values close to the noise threshold could be obtained. Due to the much higher sensitivity of MIRA36, the transition of the MRR from the true signal to noise can be observed, which agrees well with the independent clear sky noise estimate. The mean Doppler velocity differences between both radars are below 0.3 ms-1. The distribution of Z e values from MIRA36 are finally used to estimate the uncertainty of retrieved snowfall and snow accumulation with the MRR. At UFS low snowfall rates missed by the MRR are negligible when comparing snow accumulation, which were mainly caused by intensities between 0.1 and 0.8 mm h-1. The MRR overestimates the total snow accumulation by about 7%. This error is much smaller than the error caused by uncertain Z e-snowfall rate relations, which would affect the MIRA36 estimated to a similar degree.

Kneifel, Stefan; Maahn, Maximilian; Peters, Gerhard; Simmer, Clemens

2011-06-01

124

Effects of volcanic eruption and global warming on snowfall patterns in the Pacific Northwest: Survey of climate data from 36 stations  

SciTech Connect

Patterns in short term annual snowfall totals and long term glacial mass-balance of glaciers in the Pacific Northwest are affected by episodic global volcanic eruptions and the cyclic appearances of the El Nino oceanic current. A comprehensive analysis of climatic data such as snowfall, snow depth, maximum and minimum temperatures, and total precipitation was undertaken for 18 stations in Oregon and Washington between 1948-1995, and for snow-water data from 18 other stations from 1980-1995. These data were also compared to demonstrate regional variations within a given year. Snowfall maxima and Temperature minima recorded in this period closely followed major volcanic events, whereas Snowfall minima and Temperature maxima recorded in the same period coincided with periodic El Nino patterns. Snowfall totals in El Nino years were uniformly sparse region wide, whereas snowfall patterns in other years displayed some regional variation. Of special interest is the cross-correlation of snow-water and snowfall depth/totals data for the period 1980-1995, which records the patterns before and after the eruptions of Mt. Pinatubo (1991-92).

Chatelain, E.E. [Valdosta State Univ., GA (United States)

1996-09-01

125

Evidence of nonspheroidal behavior in millimeter-wavelength radar observations of snowfall  

NASA Astrophysics Data System (ADS)

Recent modeling results have indicated that, in general, idealized homogeneous spheroidal models of ice crystals and snowflakes cannot consistently describe radar backscattering from snowfall when the radar wavelengths are on the order of the snowflake size. In this paper, we provide empirical evidence supporting this prediction by analyzing collocated airborne radar measurements at 13.4 GHz, 35.6 GHz and 94 GHz. The analysis is performed by applying a recently developed method making use of two simultaneously measured dual-frequency ratios, allowing one to distinguish between the multifrequency backscattering behavior of detailed aggregate snow models and that of homogeneous spheroids. We demonstrate that in some naturally occurring cases, detailed snowflake models, which account for their complex structure, are required to describe backscattering by these particles in a manner that is consistent over multiple wavelengths. This implies that the spheroidal approximation is not always adequate as a snowflake shape model in radar retrievals at this wavelength range.

Leinonen, J.; Kneifel, S.; Moisseev, D.; Tyynelä, J.; Tanelli, S.; Nousiainen, T.

2012-09-01

126

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

127

A Winter Survival Unit.  

ERIC Educational Resources Information Center

|The article is a condensation of materials from the winter survival unit of a Canadian snow ecology course. The unit covers: cold physiology, frostbite, snowblindness, hypothermia, winter campout, and survival strategies. (SB)|

Phillips, Ronald E.

1979-01-01

128

Science of Winter  

NSDL National Science Digital Library

Science of Winter is a collection of activities, lessons, interactives, images, or other content illustrating or demonstrating scientific aspects of winter weather, conditions, processes, or phenomena, appropriate for middle school, informal education, and general audiences.

2009-07-30

129

A Winter Survival Unit.  

ERIC Educational Resources Information Center

The article is a condensation of materials from the winter survival unit of a Canadian snow ecology course. The unit covers: cold physiology, frostbite, snowblindness, hypothermia, winter campout, and survival strategies. (SB)

Phillips, Ronald E.

1979-01-01

130

A physical model to estimate snowfall over land using microwave measurements  

NASA Astrophysics Data System (ADS)

Falling snow is an important component of global precipitation in extratropical regions. This study describes the methodology and results of physically based retrievals of snow falling over land surfaces. Because microwave emitted by snow-covered surfaces are highly variable, precipitating snow above such surfaces is difficult to observe using window channels that occur at low frequencies (nu < 100 GHz). Furthermore, at frequencies nu < 37 GHz, sensitivity to liquid hydrometeors is dominant. These problems are mitigated at high frequencies (nu > 100 GHz) where water vapor screens the surface emission, and sensitivity to frozen hydrometeors is significant. However, the scattering effect of snowfall in the atmosphere at those higher frequencies is also impacted by water vapor and supercooled water in the upper atmosphere. The Discrete Dipole Approximation (DDA) method was employed to generate the single scattering parameters for nonspherical snow crystals. Comparisons show that neither equivalent spheres nor dielectric mixing theories could account for all measurements. Therefore, this study builds a look up table of the DDA calculated single scattering parameters and employs it in calculations directly. Comparisons show that DDA results calculated in this study were compatible with radar and radiometer measurements for the limited number of examples. The retrieval algorithm relied on a multi-parameter cloud model to generate the vertical structure of a snow cloud, including snow water content, snow particle effective diameter, supercooled water, and water vapor. A MM5 cloud simulation was used to provide useful statistics for generating those cloud characteristics. The snow cloud profiles and surface emissivities were then used in radiative transfer calculations that were optimized against AMSU-B observations at 89, 150, and 183.3 +/- 7, +/- 3, and +/- 1 GHz. Four variables used to adjust the snow water content, relative humidity, cloud liquid water content, and surface emissivity were sufficient to estimate snowfall rates consistent with NWS radar reflectivity measurements during the New England blizzard on March 5, 2001 and to yield a Ze-M relationship that was consistent with others reported in the literature.

Kim, Min-Jeong

131

Impact of land-use changes on snow in a forested region with heavy snowfall in Hokkaido, Japan  

Microsoft Academic Search

We simulated snow processes in a forested region with heavy snowfall in Japan, and evaluated both the regional-scale snow distribution and the potential impact of land-use changes on the snow cover and water balances over the entire domain. SnowModel reproduced the snow processes at open and forested sites, which were confirmed by snow water equivalent (SWE) measurements at two intensive

Kazuyoshi Suzuki; Yuji Kodama; Taro Nakai; Glen E. Liston; Kazukiyo Yamamoto; Tetsuo Ohata; Yoshiyuki Ishii; Akihiro Sumida; Toshihiko Hara; Takeshi Ohta

2011-01-01

132

Selection through predation, snowfall and microclimate on nest-site preferences in the Water Pipit Anthus spinoletta  

Microsoft Academic Search

Nest-site characteristics can have a strong impact on reproductive success in birds. Nest sites should simultaneously protect from predators, offer shelter and provide a favourable micro- climate. We studied the relationship between three agents of natural selection (predators (i.e. Adders and birds\\/mammals), snowfall and microclimate), nest-site characteristics and reproductive success to determine whether these influenced preference for specific nest-site characteristics

Claudia M. Rauter; Heinz-Ulrich Reyer; Kurt Bollmann

2002-01-01

133

Catastrophic winter storms: An escalating problem  

Microsoft Academic Search

Winter storms are a major weather problem in the USA and their losses have been rapidly increasing. A total of 202 catastrophic\\u000a winter storms, each causing more than $1 million in damages, occurred during 1949–2003, and their losses totaled $35.2 billion\\u000a (2003 dollars). Catastrophic winter storms occurred in most parts of the contiguous USA, but were concentrated in the eastern

2007-01-01

134

WINTER COVER CROPS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Winter cover crops (WCC) are important universal tools that can be used to conserve environmental sustainability. In general, the term 'winter cover crop' is used to describe a cover crop grown to protect the soil during the winter fallow period. A cover crop can be used even during summer, especial...

135

Winter temperature variations over the middle and lower reaches of the Yangtze River since 1736 AD  

NASA Astrophysics Data System (ADS)

We present statistically reconstructed mean annual winter (December-February) temperatures from the middle and lower reaches of the Yangtze River (24° N-34° N, 108° E-123° E within mainland China) extending back to 1736. The reconstructions are based on information regarding snowfall days from historical documents of the Yu-Xue-Fen-Cun archive recorded during the Qing Dynasty (1644-1911). This information is calibrated with regional winter temperature series spanning the period from 1951 to 2007. The gap from 1912 to 1950 is filled using early instrumental observations. With the reference period of 1951-2007, the 18th century was 0.76 °C colder, and the 19th century was 1.18 °C colder. However, since the 20th century, the climate has been in a warming phase, particularly in the last 30 yr, and the mean temperature from 1981 to 2007 was 0.25 °C higher than that of the reference period of 1951-2007, representing the highest temperatures of the past 300 yr. Uncertainty existed for the period prior to 1900, and possible causes of this uncertainty, such as physical processes involved in the interaction between temperature and snowfall days and changing of observers, are discussed herein.

Hao, Z.-X.; Zheng, J.-Y.; Ge, Q.-S.; Wang, W.-C.

2012-06-01

136

Winter World Explorations  

NSDL National Science Digital Library

Cold winter weather can cause us to retreat into our indoor shells biding our time until the warmer days return. However, there is much to explore outside during the wintertime and the following sites share some important reasons and cautionary tips for Winter World Explorations. The first website, Princeton University's Outdoor Action Guide to Winter Camping by Rick Curtis, provides a thorough overview of Winter Camping including sections on Winter Travel, Snowshoeing Basics, Winter Water, and more. This site also provides links to OA Guides for Winter Shelters, and Hypothermia and Cold Injuries (1). The second site, from the Search and Rescue Society of British Columbia deals specifically with Hypothermia including useful information on Physiology, Signs, Symptoms, and Treatment Considerations (2). The third website, SnowSchool, is an innovative educational field program designed for 4th and 5th graders where "kids venture out into America's winter wildlands to discover all the living creatures under the snow." SnowSchool is a program of Winter Wildlands Alliance and "the nation's largest on-snow winter ecology education program" with 27 sites across the United States (3). The fourth website from the Minnesota DNR is a feature on Winter Bird Feeding which includes specific information about Winter Foods, Seeds and Mixes, Suet, Feeders, and Winter Feeder Layout (4). The fifth website, The Native Conifers of North America, is an excellent and very comprehensive online introduction and field guide to conifer species native to North America. The site includes A Key to the Genera and Species, sections on Selected Conifers from Different Parts of North America, and many beautiful photographs and line drawings (5). The sixth website (6) hosts an article on Winter Nutrition: Tips for people who exercise in the cold by nutrition counselor Nancy Clark, MS, RD. In her article, Ms. Clark answers common winter exercise questions like Why do I shiver when I get cold?, and Why do I feel hungrier in the winter than in the summer? Speaking of being hungrier in the winter, the final two websites offer recipes for winter stews and soups, a perfect way to end a day of winter exploring. One website offers a Hearty Winter Stew recipe from the University of Michigan Health System-Nutrition Services (7}. The other website, from The Ohio State University Extension -- Family Nutrition Program Newsletter tells us that January is National Soup Month, and offers recipes for stews, soups, and even instructions for bread soup bowls (8).

137

Determination of Winter Habitat of Large Brown Trout in Southeast Minnesota Streams Using Radiotelemetry. Study 656.  

National Technical Information Service (NTIS)

Availability of suitable winter habitat can limit abundance of large brown trout Salmo trutta in streams, making it vital to determine winter habitat requirements when managing to increase abundance of these fish. We used radiotelemetry to identify winter...

T. D. Marwitz W. C. Thorn C. S. Anderson

2002-01-01

138

Winter leaf reddening in 'evergreen' species.  

PubMed

Leaf reddening during autumn in senescing, deciduous tree species has received widespread attention from the public and in the scientific literature, whereas leaf reddening in evergreen species during winter remains largely ignored. Winter reddening can be observed in evergreen herbs, shrubs, vines and trees in Mediterranean, temperate, alpine, and arctic regions, and can persist for several months before dissipating with springtime warming. Yet, little is known about the functional significance of this colour change, or why it occurs in some species but not others. Here, the biochemistry, physiology and ecology associated with winter leaf reddening are reviewed, with special focus on its possible adaptive function. Photoprotection is currently the favoured hypothesis for winter reddening, but alternative explanations have scarcely been explored. Intraspecific reddening generally increases with sunlight incidence, and may also accompany photosynthetic inferiority in photosynthetically 'weak' (e.g. low-nitrogen) individuals. Red leaves tend to show symptoms of shade acclimation relative to green, consistent with a photoprotective function. However, winter-red and winter-green species often cohabitate the same high-light environments, and exhibit similar photosynthetic capacities. The factors dictating interspecific winter leaf colouration therefore remain unclear. Additional outstanding questions and future directions are also highlighted, and possible alternative functions of winter reddening discussed. PMID:21375534

Hughes, Nicole M

2011-03-04

139

Early Childhood: The World in Winter.  

ERIC Educational Resources Information Center

Various winter activities and experiences for young children are suggested. These include a getting ready for winter walk in the fall, winter birds, winter clothing, traveling in winter, winter sky watch, and others. (JN)

McIntyre, Margaret, Ed.

1983-01-01

140

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 ...

Keller, Mrs.

2010-01-23

141

Winter Vehicle Traction and Controllability Performance.  

National Technical Information Service (NTIS)

Snow and ice conditions have been considered the main factors that contribute to reduced vehicle traction forces and potential traffic accidents during winter seasons. To increase a vehicle's traction forces on snow and icy surfaces, studded and non-studd...

J. J. Lu

1995-01-01

142

Tree-ring-based snowfall record for cold arid western Himalaya, India since A.D. 1460  

NASA Astrophysics Data System (ADS)

Understanding snowfall variations in high-elevation cold arid regions of the western Himalaya is important as snowmelt water is the main source of water to meet the scores of socioeconomic needs. The ground-based observational data, though limited to the last two decades, show decreasing snowfall, raising the concern of looming water scarcity in the region. The tree-ring data of Himalayan cedar from a network of six moisture-stressed sites, where snowmelt water is the sole source of soil moisture for tree growth, were used to develop the November-April snow water equivalent (SWE) extending back to A.D. 1460. The reconstruction revealed persistent severe droughts in the 1780s followed by the 1480s and relatively lesser magnitude droughts in the 1540s-1560s, 1740s, and early twentieth century. The pluvial conditions observed in 1948-1958 and 1986-1996 stand out over any other period of such duration. The SWE reconstruction revealed large-scale spatial coherence with the corresponding month's Palmer Drought Severity Index over the western Himalayan region. Significant relationship observed between SWE reconstruction and January-March Chenab River flow revealed its potential utility in understanding water resource availability in the long-term perspective.

Yadav, Ram R.; Bhutiyani, Mahendra R.

2013-07-01

143

Lakota Winter Counts  

NSDL National Science Digital Library

Different human societies across the millennia have sought to record their histories in a multitude of ways, and the Lakota people of the Northern Plains elected to record their experiences through what are known as winter counts. These winter counts are essentially histories or calendars in which events are recorded by pictures, with one picture for each year. These rather fascinating documents were used in conjunction with extensive oral histories, and as such, most of these events were widely known and recognized by a majority of the Lakota. This particular website from the National Anthropological Archives at the Smithsonian National Museum of Natural History allows visitors to view these winter counts, learn more about the Lakota, and view interviews with contemporary Lakota people about the winter counts. The site also contains an audio glossary and a number of helpful resources for educators.

144

Yuma Winter Microclimate.  

National Technical Information Service (NTIS)

This study consists of an analysis of winter temperatures at and near the ground and wind velocities at standard heights, at three sites within Yuma Proving Ground. Two of the sites were selected for their representativeness of surface types characterizin...

H. L. Ohman R. L. Pratt

1966-01-01

145

Concussion in Winter Sports  

MedlinePLUS

... to... Añadir en... Favorites Delicious Digg Google Bookmarks Concussion in Winter Sports Get prepared for concussions on and off the ... professionals Learn more about CDC's Heads Up initiatives . Concussion in Sports NFL/CDC Poster for Professional Players and Young ...

146

Winter Weather Emergencies  

MedlinePLUS

... there are no guarantees of safety during winter weather emergencies, you can take actions to protect yourself. You should have a disaster plan. Being prepared can help reduce fear, anxiety and losses. Centers for Disease Control and Prevention

147

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 ...

Haight, Jennifer

2010-02-22

148

Simulation of Annual Snowfall over Colorado using a High Resolution Mesoscale Model and some Impacts of Climate Change using the Pseudo Climate Simulation Method  

NASA Astrophysics Data System (ADS)

Snowpack is the most important water resource in the Western United States, and widely regarded as the most vulnerable. It is thus critical to provide water managers the most accurate estimate of how that resource will evolve as the climate changes, including its societal impact. The headwaters region of Colorado that includes, among others, the Colorado, Platte, Rio Grande and Arkansas Rivers, is one of the key source regions for water in the Southwest as ~85% of the streamflow for the Colorado River comes from snowmelt in this region. This region is a particularly difficult area for global climate models to properly handle, with inconsistent snowpack trends in this region from different models despite consistent predictions of temperature increases in this region from all climate models from both the 3rd and 4th IPCC reports (2001, 2007). Observations over the past 50 years in the upper Colorado River basin also reflect the same increasing temperature trend but show no identifiable trends in snowpack (Edwards and Redmond, 2005, Colorado and California Water Users Conference publication). A recent analysis of the 2007 IPCC 4th Assessment global models by Hoerling and Eischeid (2006,Southwest Hydrology) indicates that the combination of increased temperature and weak to no trends in snowfall will produce unprecedented drought conditions over the next 50 years in the Southwest due to a strong increase in evapotranspiration associated with the increased temperature. While the above predictions based on global models indicate dire consequences for the Southwest, it should also be noted that the AR4 indicates that global models typically perform poorly in mountainous regions due to the poor depiction of terrain as well as significant uncertainty in detailed hydrometeorological processes (i.e. cloud/precipitation microphysics, embedded convection and cloud-scale circulations, snowpack and snow ablation, and runoff generation in complex terrain) that currently limit model simulation skill. Colorado's headwaters region is dominated by high altitude snow melt, so climate assessments in this region using global models are particularly uncertain. However, simple increases in model resolution without clearer understanding and representation of hydroclimatic processes controlling water resources will not be sufficient for improving model performance. It is therefore critical to examine climate impacts in this region using detailed coupled atmosphere-hydrology models in order to more realistically simulate precipitation, sublimation, and runoff processes, as well as their impact on managed water systems. This paper will present results of annual snowfall, snow/rain fraction, and snowpack over Colorado based on high resolution simulations of the Weather Research and Forecast (WRF) model running at 2 km horizontal resolution using the North American Regional Reanalysis (NARR) as initial and lateral boundary conditions. Four retrospective years will be shown. Results from four Pseudo Climate simulations (Hara et al. 2008) using the four retrospective runs as the baseline will also be presented. These simulations will be forced by the mean monthly climate signal difference between current (1995 - 2004) and 2045-2055 mean conditions. The NCAR CCSM3 A1B AR4 climate runs with 6 hourly output will be used for the current and future climate model forcings.

Rasmussen, R.; Grubisic, V.

2010-09-01

149

Warmest winter in history  

NSDL National Science Digital Library

For four days last week, the daily temperatures outside the Internet Scout Project office here in Wisconsin soared above 60 F (and on one day, above 75 F), and the lakes that surround Madison melted in one fell swoop, bringing winter to a lurching halt and restless thoughts of summer to the forefront. While such local temperature anomalies are not surprising (nor did other cities experience the same highs), in this case, they fit in with a global trend that continues to raise -- in some cases, anxious -- eyebrows. On Friday, the National Oceanic and Atmospheric Administration (NOAA) announced that this winter is the warmest on record. Surpassing recent warm winter records of 1997-1998, the winter of 1999-2000 has now clinched the somewhat dubious title of warmest winter in history. This news release comes on the coat tails of a January report from the National Academy of Sciences confirming what is already accepted among most scientists -- that global warming is real (see the January 14, 2000 Scout Report). For news and information on this warmest of winters, this week's In The News features seven sites, listed above.

Payne, Laura X.

150

Lessons learned from the snow emergency management of winter season 2008-2009 in Piemonte  

NASA Astrophysics Data System (ADS)

The winter season 2008-2009 has been characterized by heavy snowfalls over the whole Piemonte, in the Western Alps region. The snowfalls have been exceptional because of their earliness, persistence and intensity. The impact on the regional environment and territory has been relevant, also from the economical point of view, as well as the effort of the people involved in the forecasting, prevention and fighting actions. The environmental induced effects have been shown until late spring. The main critical situations have been arisen from the snowfalls earliness in season, the several snow precipitation events over the plains, the big amount of snow accumulation on the ground, as well as the anomaly with respect to the last 30 years climatic trend of snow conditions in Piemonte. The damage costs to the public property caused by the snowfalls have been estimated by the Regione Piemonte to be 470 million euros, giving evidence of the real emergency dimension of the event, never occurred during the last 20 years. The technical support from the Regional Agency for Environmental Protection of Regione Piemonte (Arpa Piemonte) to the emergency management allowed to analyse and highlight the direct and induced effects of the heavy snowfalls, outlining risk scenarios characterized by different space and time scales. The risk scenarios deployment provided a prompt recommendation list, both for the emergency management and for the natural phenomena evolution surveillance planning to assure the people and property safety. The risk scenarios related to the snow emergency are different according to the geographical and anthropic territory aspects. In the mountains, several natural avalanche releases, characterized frequently by a large size, may affect villages, but they may also interrupt the main and secondary roads both down in the valleys and small villages road access, requiring a long time for the complete and safe snow removal and road re-opening. The avalanches often cause the service breakdowns and damage the infrastructures in the built-up areas and the forest heritage. Critical situations due to the snow loading and the snow removal necessity involve all the mountain people directly. Over the plain and the hill country, where the new snow density is generally high giving rise to effects related to its load capacity, to the isolation of little residential and rural settlements, several damages on the secondary road system due to the tree and tree branch falls comes up , together with many public services interruptions (electric power and telephone), warehouse and barn collapses, determining a widespread critical situation. The urban and commuting traffic during the snow emergency enhances the difficulties related to the road management and traffic control over the whole road system in the plains, even with little snow accumulation on the ground. Critical situations may also arise from road frost and intense freezing spells. The operational implementation of the technical rules for the snow emergency management, tested the first time during the event in a dynamic way, pointed out its drawbacks and potentiality, highlighting the "emergency preparedness" importance at different institutional levels, with the population and stakeholder involvement. Some measures have to be especially underlined: the coordination of the snow monitoring over the territory performed by the local operators (avalanche activity and linked damages reporting) and the steps taken locally; the improvement of the tools for the snow pack evaluation to drive the avalanche artificial triggering off, in case of snow mass hazard assessment, and their regional coordination. Moreover it is important to define the standard, acknowledged and accepted prevention actions suited to minimize the heavy snowfall effects, with particular attention to the viableness,to the school systemopening/closing and to the preventive information care in order to avoid the missing perception of the risk. Special attention must be paid to the hydrogeological risk condition ass

Bovo, Dr.; Pelosini, Dr.; Cordola, Dr.

2009-09-01

151

The effect of topography and sea surface temperature on heavy snowfall in the Yeongdong region: A case study with high resolution WRF simulation  

NASA Astrophysics Data System (ADS)

An analysis of the heavy snowfall that occurred on 11-14 February 2011 in the Yeongdong region along the eastern coast is presented. Relevant characteristics based on observation and model simulations are discussed with a focus on the times of maximum snowfall in Gangneung (GN) and Daegwallyong (DG). This event was considered part of the typical snowfall pattern that frequently occurs in the Yeongdong region due to the prevailing northeasterly flow. The control simulation using the high resolution Weather Research and Forecasting (WRF) model (1 km × 1 km) showed reasonable performance in capturing the spatial distribution and temporal evolution of precipitation. The area of precipitation maxima appeared to propagate from the plain coastal region further into the inland mountainous region, in relation to the location of convergence zone. In addition, a series of sensitivity experiments were performed to investigate the effect of topography and sea surface temperature (SST) on the formation of heavy snowfall. The change of topography tended to modulate the topographically induced mechanical flow, and thereby modify the precipitation distribution, which highlights the importance of an elaborate representation of the topography. On the other hand, the sensitivity experiment to prescribe positive (negative) SST forcing shows the enhanced (suppressed) precipitation amount due to the change of the sensible and latent heat fluxes.

Jung, Sun-Hee; Im, Eun-Soon; Han, Sang-Ok

2012-08-01

152

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

153

Mountaintop and radar measurements of anthropogenic aerosol effects on snow growth and snowfall rate  

NASA Astrophysics Data System (ADS)

A field campaign designed to investigate the second indirect aerosol effect (reduction of precipitation by anthropogenic aerosols which produce more numerous and smaller cloud droplets) was conducted during winter in the northern Rocky Mountains of Colorado. Combining remote sensing and in-situ mountain-top measurements it was possible to show higher concentrations of anthropogenic aerosols (~1 ?g m-3) altered the microphysics of the lower orographic feeder cloud to the extent that the snow particle rime growth process was inhibited, or completely shut off, resulting in lower snow water equivalent precipitation rates.

Borys, Randolph D.; Lowenthal, Douglas H.; Cohn, Stephen A.; Brown, William O. J.

2003-05-01

154

High Resolution Simulation of Annual Snowfall and Snowpack over Colorado and some Impacts of Climate Change using the Pseudo Climate Simulation Method  

NASA Astrophysics Data System (ADS)

Snowpack is the most important water resource in the Western United States, and widely regarded as the most vulnerable. It is thus critical to provide water managers the most accurate estimate of how that resource will evolve as the climate changes, including its societal impact. The headwaters region of Colorado that includes, among others, the Colorado, Platte, Rio Grande and Arkansas Rivers, is one of the key source regions for water in the Southwest as ~85% of the streamflow for the Colorado River comes from snowmelt in this region. This region is a particularly difficult area for global climate models to properly handle, with inconsistent snowpack trends in this region from different models despite consistent predictions of temperature increases in this region from all climate models from both the 3rd and 4th IPCC reports (2001, 2007). A recent analysis of the 2007 IPCC 4th Assessment global models by Hoerling and Eischeid (2006,Southwest Hydrology) indicates that the combination of increased temperature and weak to no trends in snowfall will produce unprecedented drought conditions over the next 50 years in the Southwest due to a strong increase in evapotranspiration associated with the increased temperature. While the above predictions based on global models indicate dire consequences for the Southwest, it should also be noted that the AR4 indicates that global models typically perform poorly in mountainous regions due to the poor depiction of terrain as well as significant uncertainty in detailed hydrometeorological processes (i.e. cloud/precipitation microphysics, embedded convection and cloud-scale circulations, snowpack and snow ablation, and runoff generation in complex terrain) that currently limit model simulation skill. Colorado’s headwaters region is dominated by high altitude snow melt, so climate assessments in this region using global models are particularly uncertain. It is therefore critical to examine climate impacts in this region using detailed coupled atmosphere-hydrology models in order to more realistically simulate precipitation, sublimation, and runoff processes, as well as their impact on managed water systems. This paper will present results of annual snowfall, snow/rain fraction, and snowpack over Colorado based on high resolution simulations of the Weather Research and Forecast (WRF) model running at 2 km horizontal resolution using the North American Regional Reanalysis (NARR) as initial and lateral boundary conditions. Four retrospective years will be shown. Results from four Pseudo Climate simulations (Hara et al. 2008) using the four retrospective runs as the baseline will also be presented. These simulations will be forced by the mean monthly climate signal difference between current (1995 - 2004) and 2045-2055 mean conditions. The NCAR CCSM3 A1B AR4 climate runs with 6 hourly output will be used for the current and future climate model forcings.

Rasmussen, R.; Ikeda, K.; Liu, C.; Gochis, D.; Chen, F.; Tewari, M.; Dudhia, J.; Thompson, G.; Barlage, M. J.; Miller, K.; Yates, D.; Grubisic, V.; Arsenault, K.

2009-12-01

155

Winter mortality and its causes.  

PubMed

In the 1970s scientific research focussed for the first time on dramatic rises in mortality every winter, and on smaller rises in unusually hot weather. Following the recent decline in influenza epidemics, approximately half of excess winter deaths are due to coronary thrombosis. These peak about two days after the peak of a cold spell. Approximately half the remaining winter deaths are caused by respiratory disease, and these peak about 12 days after peak cold. The rapid coronary deaths are due mainly to haemoconcentration resulting from fluid shifts during cold exposure; some later coronary deaths are secondary to respiratory disease. Heat related deaths often result from haemoconcentration resulting from loss of salt and water in sweat. With the possible exception of some tropical countries, global warming can be expected to reduce cold related deaths more than it increases the rarer heat related deaths, but statistics on populations in different climates suggest that, given time, people will adjust to global warming with little change in either mortality. Some measures may be needed to control insect borne diseases during global warming, but current indications are that cold will remain the main environmental cause of illness and death. Air pollution in cities may also still be causing some deaths, but these are hard to differentiate from the more numerous deaths due to associated cold weather, and clear identification of pollution deaths may need more extensive data than is currently available. PMID:12546188

Keatinge, W R

2002-11-01

156

Greenland Ice Sheet: Increased coastal thinning  

Microsoft Academic Search

Repeated laser-altimeter surveys and modelled snowfall\\/summer melt show average ice loss from Greenland between 1997 and 2003 was 80 +\\/- 12 km3 yr-1, compared to about 60 km3 yr-1 for 1993\\/4-1998\\/9. Half of the increase was from higher summer melting, with the rest caused by velocities of some glaciers exceeding those needed to balance upstream snow accumulation. Velocities of one

W. Krabill; E. Hanna; P. Huybrechts; W. Abdalati; J. Cappelen; B. Csatho; E. Frederick; S. Manizade; C. Martin; J. Sonntag; R. Swift; R. Thomas; J. Yungel

2004-01-01

157

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 ...

S., Tasia

2010-09-23

158

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.

159

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 ...

Miller, Aubree

2009-09-28

160

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

161

The News. Winter 2007  

ERIC Educational Resources Information Center

|This Winter 2007 quarterly newsletter from the Community College League of California includes: (1) Incumbents: Some Win, Some Lose in November Trustee Elections; (2) Voters Approve $2 Billion in Bonds; (3) Photos from the "Together We Can" conference; (4) Report, Media Criticize Transfer, Completion Rates and Colleges; (5) District Leader…

Giles, Ray, Ed.

2007-01-01

162

Teaching Ecology in Winter.  

ERIC Educational Resources Information Center

|Presents ideas for teaching ecology in the winter. Suggested topic areas or units include snow insulation and density, snowflakes and snow crystals, goldenrod galls, bird behavior, survival techniques, bacteriology and decomposition, trees and keying, biomass and productivity, pollution, and soil organisms. A sample student activity sheet is…

Clearing: Nature and Learning in the Pacific Northwest, 1984

1984-01-01

163

Unusual Winter Storm, Hawaii.  

National Technical Information Service (NTIS)

From January 8 to 11, 1980, the Hawaiian Islands experienced some of the most severe weather from a winter storm in recent years. Even though rainfall was over 20 inches in some places, the most noteworthy and damaging aspects of this storm episode were t...

H. E. Rosendal

1980-01-01

164

Winter storms over Canada  

Microsoft Academic Search

Various type of winter storms occur over Canada and produce major impacts on society. Canada is subjected to extra?tropical cyclones with all their embedded structures, as well as blizzards, mountain?induced storms, lake effect storms and polar lows. Many of these storms are accompanied by heavy precipitation in the form of snow or freezing precipitation, bitterly cold conditions, strong winds, and

R. E. Stewart; D. Bachand; R. R. Dunkley; A. C. Giles; B. Lawson; L. Legal; S. T. Miller; B. P. Murphy; M. N. Parker; B. J. Paruk; M. K. Yau

1995-01-01

165

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

166

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.

167

The History of Winter: A Professional Development "Teacher as Scientist" Experiential Learning Field Experience.  

NASA Astrophysics Data System (ADS)

Each year since 2000, the NASA Goddard History of Winter (HOW) program has allowed teachers to develop an understanding of the consequences of one segment of the orbit of the tilted Earth in its path around the sun. Scientists from NASA, CRREL, and Michigan Tech, supported by the Whiteface Observatory, and the science program at Northwood School in Lake Placid, New York, use the weather and the stratigraphy in the ice and snow, consequences of the weather changes, as "teachers" in a team study of the winter record. Snow in the air and on the ground, ice, its crystal structure and axial orientation, and the ecosystem consequences of snow and ice constitute the weeklong content package. Teacher Professional Development Standards A, B, C, and D were the guiding principles in developing HOW with a content structure formulated as protocols to serve as inserts into lesson plans and inquiry guides. The concept of HOW within NASA is to provide understanding of the WHY? and WHAT? of satellite remote sensing. The content is appropriate ground validation in that techniques presented in protocols are identical to those used by professionals who study snow pits, evaluate features in snow metamorphism, and study thin sections of ice cores drilled in ice caps and glaciers. The HOW Teacher as scientist (TAS) model is a flexible model. HOW enables teachers who are required to use inquiry-based facilitation in the classroom to experience inquiry themselves. Teachers with little science content background as well as those with Science degrees have participated in HOW working alongside of the science team. Accommodations are made through differentiation of instruction so that each group leaves with a mastery of the content that is appropriate for the transition to presentation in the classroom. Each year builds on the previous year ensuring a time series record of the history of winter-by itself a learning experience. An offshoot of the NASA Goddard Center History of Winter (HOW) Program, the Global Snowflake Network (GSN) launched in the winter of 2006 engages an international audience including both formal and informal education groups. The goal is to provide an interactive online data resource in science and education for the characterization of snowfall and related weather systems. The Global Snowflake Network has been accepted as an education outreach proposal for the International Polar Year. Collaborations with other agencies and universities also with IPY-accepted proposals are now underway. HOW and the GSN are endorsed by the NASA Goddard Education Office and many of the Goddard Snow and Ice Team scientists. Together these programs offer a unique, sustainable, and proven outreach for the Cryosphere research program. Snowflakes are like frozen data points, their shape is a record of atmospheric conditions at the time of their formation. The shapes of snowflakes vary over the winter season, with the source of a weather system and over the course of a given snowfall. The objective of the Global Snowflake Network (GSN) is to create a global ground team of teachers, students, families, and researchers worldwide to identify snowflake types during the progress of snowfalls. The result is a unique and scientifically valid resource useful to meteorology and scientific modeling of Earth's Hydrosphere. The Global Snowflake Network (GSN), simultaneously a science program and an education program is presented as a simple, scientifically valid project that has the potential to spread the IPY message and produce a lasting resource to further scientific understanding of Earth's hydrology through the study of snow.

Gabrys, R. E.

2007-12-01

168

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

2011-09-01

169

Russian winter wheat mosaic virus  

Technology Transfer Automated Retrieval System (TEKTRAN)

The chapter contains a description of the Winter wheat (Russian) mosaic disease symptoms, transmission and occurrence. Characteristics of the disease agent, Winter wheat (Russian) mosaic virus are outlined, as are control measures....

170

WINTERING BALD EAGLE TRENDS IN NORTHERN ARIZONA, 1975–2000  

Microsoft Academic Search

Between 1975 and 2000, 4,525 sightings of wintering bald eagles (Haliaeetus leucoce- phalus) were recorded at Mormon Lake in northern Arizona. Numbers of wintering eagles fluc- tuated little in the 20 years from 1975 through 1994 (5.5 6 3.0 mean sightings per day). However, during the winters of 1995 through 1997 local record highs of 59 to 118 eagles increased

Teryl G. Grubb; William H. Baltosser

2003-01-01

171

Winter Cardiovascular Diseases Phenomenon  

PubMed Central

This paper review seasonal patterns across twelve cardiovascular diseases: Deep venous thrombosis, pulmonary embolism, aortic dissection and rupture, stroke, intracerebral hemorrhage, hypertension, heart failure, angina pectoris, myocardial infarction, sudden cardiac death, venricular arrythmia and atrial fibrillation, and discuss a possible cause of the occurrence of these diseases. There is a clear seasonal trend of cardiovascular diseases, with the highest incidence occurring during the colder winter months, which have been described in many countries. This phenomenon likely contributes to the numbers of deaths occurring in winter. The implications of this finding are important for testing the relative importance of the proposed mechanisms. Understanding the influence of season and other factors is essential when seeking to implement effective public health measures.

Fares, Auda

2013-01-01

172

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 ...

Butcher, Kirsten

2008-09-26

173

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

174

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

175

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

176

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

177

Winter 1994 Weather and Ice Conditions for the Laurentian Great Lakes.  

NASA Astrophysics Data System (ADS)

The Laurentian Great Lakes developed their most extensive ice cover in over a decade during winter 1994 [December-February 1993/94 (DJF 94)]. Extensive midlake ice formation started the second half of January, about 2 weeks earlier than normal. Seasonal maximal ice extent occurred in early February, again about 2 weeks earlier than normal. Winter 1994 maximum (normal) ice coverages on the Great Lakes are Lake Superior 96% (75%), Lake Michigan 78% (45%), Lake Huron 95% (68%), Lake Erie 97% (90%), and Lake Ontario 67% (24%). Relative to the prior 31 winters (1963-93), the extent of seasonal maximal ice cover for winter 1994 for the Great Lakes taken as a unit is exceeded by only one other winter (1979); however, other winters for individual Great Lakes had similar maximal ice covers.Anomalously strong anticyclonic circulation over the central North Pacific (extending to the North Pole) and an abnormally strong polar vortex centered over northern Hudson Bay combined to produce a circulation pattern that brought frequent air masses of Arctic and polar origin to the eastern third of North America. New records were set for minimum temperatures on 19 January 1994 at many locations in the Great Lakes region. A winter severity index consisting of the average November-February air temperatures averaged over four sites on the perimeter of the Great Lakes (Duluth, Minnesota; Sault Ste. Marie, Michigan; Detroit, Michigan; and Buffalo, New York) indicates that winter 1994 was the 21st coldest since 1779. The unseasonably cold air temperatures produced much-above-normal ice cover over the Great Lakes and created problems for lake shipping. Numerous fatalities and injuries were attributed to the winter weather, which included several ice and snow storms. The much-below-normal air temperatures resulted in enhanced lake-effect snowfall along downwind lake shores, particularly during early to midwinter, prior to extensive ice formation in deeper lake areas. The low air temperatures were also responsible for record 1-day electrical usage and multimillion dollar costs associated with snow removal, U.S. and Canadian Coast Guard operational assistance to ships beset in ice, damage to ships by ice, damage to public and private property by river ice jams and associated flooding, frozen underground water pipes, and damage to fruit trees.

Assel, Raymond A.; Janowiak, John E.; Young, Sharolyn; Boyce, Daron

1996-01-01

178

Winter Biological Processes Could Help Convert Arctic Tundra to Shrubland  

Microsoft Academic Search

In arctic Alaska, air temperatures have warmed 0.5 degrees Celsius (?C) per decade for the past 30 years, with most of the warming coming in winter. Over the same period, shrub abundance has increased, perhaps a harbinger of a conversion of tundra to shrubland. Evidence suggests that winter biological processes are contributing to this conversion through a positive feedback that

MATTHEW STURM; JOSH SCHIMEL; GARY MICHAELSON; JEFFREY M. WELKER; STEVEN F. OBERBAUER; GLEN E. LISTON; JACE FAHNESTOCK; VLADIMIR E. ROMANOVSKY

2005-01-01

179

Variation In Winter Hardiness Among Safflower Accessions  

Technology Transfer Automated Retrieval System (TEKTRAN)

Fall planted safflower (Carthamus tinctorius L.) would provide management alternatives in crop rotations and potentially increase yield. Our objective was to relate several fall growth factors to winter survival in a diverse set of 11 safflower accessions grown at Central Ferry and Pullman WA, USA....

180

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 ...

Prested, Miss

2010-05-26

181

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 ...

Cook, Mrs.

2010-11-05

182

Duration of prepupal summer dormancy regulates synchronization of adult diapause with winter temperatures in bees of the genus Osmia  

Technology Transfer Automated Retrieval System (TEKTRAN)

Osmia (Osmia) bees are strictly univoltine and winter as diapausing adults. In these species, the timing of adult eclosion with the onset of wintering conditions is critical, because adults exposed to long pre-wintering periods show increased lipid loss and winter mortality. Populations from warm ar...

183

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

184

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

185

Changes in Soil Water Storage in Winter Fallowed and Cover Cropped Soils  

Microsoft Academic Search

The use of winter cover crops to improve the productivity and sustainability of agroecosystems in California has increased during the last decade. Little information exists however, on water use by winter cover crops. This 3-year study was conducted in the Central Valley of California to quantify changes in water storage in winter fallowed and cover cropped soils. Soil water depletions

J. P. Mitchell; D. W. Peters; C. Shennan

1999-01-01

186

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

187

Perspectives in winter limnology: closing the annual cycle of freezing lakes  

Microsoft Academic Search

Winter has traditionally been considered as an ecologically insignificant season and, together with technical difficulties,\\u000a this has led winter limnology to lag behind summer limnology. Recently, rapidly expanding interest in climate warming has\\u000a increased water research in winter. It has also become clear that neither winter conditions of lakes nor under-ice communities\\u000a are as static as often supposed. Although interannual

K. Salonen; M. Leppäranta; M. Viljanen; R. D. Gulati

2009-01-01

188

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

189

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

190

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

191

Lemming winter habitat choice: a snow-fencing experiment.  

PubMed

The insulative value of early and deep winter snow is thought to enhance winter reproduction and survival by arctic lemmings (Lemmus and Dicrostonyx spp). This leads to the general hypothesis that landscapes with persistently low lemming population densities, or low amplitude population fluctuations, have a low proportion of the land base with deep snow. We experimentally tested a component of this hypothesis, that snow depth influences habitat choice, at three Canadian Arctic sites: Bylot Island, Nunavut; Herschel Island, Yukon; Komakuk Beach, Yukon. We used snow fencing to enhance snow depth on 9-ha tundra habitats, and measured the intensity of winter use of these and control areas by counting rodent winter nests in spring. At all three sites, the density of winter nests increased in treated areas compared to control areas after the treatment, and remained higher on treated areas during the treatment. The treatment was relaxed at one site, and winter nest density returned to pre-treatment levels. The rodents' proportional use of treated areas compared to adjacent control areas increased and remained higher during the treatment. At two of three sites, lemmings and voles showed significant attraction to the areas of deepest snow accumulation closest to the fences. The strength of the treatment effect appeared to depend on how quickly the ground level temperature regime became stable in autumn, coincident with snow depths near the hiemal threshold. Our results provide strong support for the hypothesis that snow depth is a primary determinant of winter habitat choice by tundra lemmings and voles. PMID:22042523

Reid, Donald G; Bilodeau, Frédéric; Krebs, Charles J; Gauthier, Gilles; Kenney, Alice J; Gilbert, B Scott; Leung, Maria C-Y; Duchesne, David; Hofer, Elizabeth

2011-10-29

192

Winter Cooling of Arctic Fields.  

National Technical Information Service (NTIS)

The crystallization heat given off by the ice to the atmosphere and its effect on meteorological conditions in the Arctic is analyzed on the basis of observational data and theoretical computations. In connection with this, the interrelation of winter coo...

A. A. Drogaitsev

1971-01-01

193

Survival in the Winter Storm.  

National Technical Information Service (NTIS)

Deals with the dangers inherent in winter weather. Gives advice to the average citizen on how to prepare for severe weather conditions, explains the meaning of specific forecasts, and pints up the necessity for emergency planning by local governments.

1994-01-01

194

Survival in the Winter Storm.  

National Technical Information Service (NTIS)

Deals with the dangers inherent in winter weather. Gives advice to the average citizen on how to prepare for severe weather conditions, explains the meanings of specific forecasts, and points up the necessity for emergency planning by local governments.

1994-01-01

195

The Challenge of Winter Backpacking.  

ERIC Educational Resources Information Center

Tips and techniques for safe and enjoyable winter backpacking are offered. Topics covered include cross county skis, snowshoes, clothing, footwear, shelter, sleeping bags, food, hypothermia prevention, as well as general rules and requirements. (CO)

Cavanaugh, Michael; Mapes, Alan

1981-01-01

196

Community Ordination Utilizing Winter Stoneflies  

NSDL National Science Digital Library

This exercise in community ecology can be carried out in mid-winter and introduces participants to useful taxonomic and statistical procedures. Species determinations of winter stoneflies are facilitated by a computerized key featuring color illustrations. Taxonomic data are used to construct a two-dimensional ordination of the communities from which specimens were collected. Correlations are then sought between differences exhibited by communities and gradients of environmental conditions.

Vinnedge M. Lawrence (Washington and Jefferson College;)

2008-04-11

197

A comparison of winter mercury accumulation at forested and no-canopy sites measured with different snow sampling techniques  

USGS Publications Warehouse

Atmospheric mercury (Hg) is delivered to ecosystems via rain, snow, cloud/fog, and dry deposition. The importance of snow, especially snow that has passed through the forest canopy (throughfall), in delivering Hg to terrestrial ecosystems has received little attention in the literature. The snowpack is a dynamic system that links atmospheric deposition and ecosystem cycling through deposition and emission of deposited Hg. To examine the magnitude of Hg delivery via snowfall, and to illuminate processes affecting Hg flux to catchments during winter (cold season), Hg in snow in no-canopy areas and under forest canopies measured with four collection methods were compared: (1) Hg in wet precipitation as measured by the Mercury Deposition Network (MDN) for the site in Acadia National Park, Maine, USA, (2) event throughfall (collected after snowfall cessation for accumulations of >8 cm), (3) season-long throughfall collected using the same apparatus for event sampling but deployed for the entire cold season, and (4) snowpack sampling. Estimates (mean ?? SE) of Hg deposition using these methods during the 91-day cold season in 2004-2005 at conifer sites showed that season-long throughfall Hg flux (1.80 ??g/m2) < snowpack Hg (2.38 ?? 0.68 ??g/m2) < event throughfall flux (5.63 ?? 0.38 ??g/m2). Mercury deposition at the MDN site (0.91 ??g/m2) was similar to that measured at other no-canopy sites in the area using the other methods, but was 3.4 times less than was measured under conifer canopies using the event sampling regime. This indicates that snow accumulated under the forest canopy received Hg from the overstory or exhibited less re-emission of Hg deposited in snow relative to open areas. The soil surface of field-scale plots were sprayed with a natural rain water sample that contained an Hg tracer (202Hg) just prior to the first snowfall to explore whether some snowpack Hg might be explained from soil emissions. The appearance of the 202Hg tracer in the snowpack (0-64% of the total Hg mass in the snowpack) suggests that movement of Hg from the soil into the snowpack is possible. However, as with any tracer study the 202Hg tracer may not precisely represent the reactivity and mobility of natural Hg in soils. ?? 2007 Elsevier Ltd. All rights reserved.

Nelson, S. J.; Johnson, K. B.; Weathers, K. C.; Loftin, C. S.; Fernandez, I. J.; Kahl, J. S.; Krabbenhoft, D. P.

2008-01-01

198

Nuclear winter attracts additional scrutiny  

SciTech Connect

Prodded by the Natural Resources Defense Council, Congress has asked the Pentagon to provide what amounts to an environmental impact statement on the potential for nuclear weapons explosions to create enough soot and dust to cause a nuclear winter. The request has implications for arms control and civil defense as well as for weapons procurement and deployment. Little attention was given to the atmospheric and climatic effects of nuclear war until the nuclear winter concept was introduced in October of 1983. Only the Navy and the DOE took steps to follow up until pressure was put on Congress and the Pentagon for further study. Pentagon criticism of the nuclear winter presentation argues that the scenario assumptions that cities will be targeted and that a conflict will involve 5000-6500 megatons are incorrect.

Smith, R.J.

1984-07-06

199

RESPONSE OF NO-TILL WINTER WHEAT TO PLANT DENSITY  

Technology Transfer Automated Retrieval System (TEKTRAN)

Because no-till has increased the amount of soil water available, producers are asking if seeding rates for winter wheat should be increased to improve grain yields. The conventional seeding rate has been 45 lbs/ac. With no-till, seeding rate studies indicate that increasing the seeding rate to 65...

200

Distribution patterns during winter and fidelity to wintering areas of American black ducks  

USGS Publications Warehouse

The distribution patterns during winter of American black ducks were compared among age-sex classes using band recivery data. In addition, fidelity to wintering areas was compared between sexes and between coastal and inland wintering sites.

Diefenbach, D.R.; Nichols, J.D.; Hines, J.E.

1988-01-01

201

Hatchling turtles survive freezing during winter hibernation.  

PubMed Central

Hatchlings of the painted turtle (Chrysemys picta marginata) are unique as the only reptile and highest vertebrate life form known to tolerate the natural freezing of extracellular body fluids during winter hibernation. Turtles survived frequent exposures to temperatures as low as -6 degrees C to -8 degrees C in their shallow terrestrial nests over the 1987-1988 winter. Hatchlings collected in April 1988 had a mean supercooling point of -3.28 +/- 0.24 degrees C and survived 24 hr of freezing at -4 degrees C with 53.4% +/- 1.98% of total body water as ice. Recovery appeared complete after 20 hr of thawing at 3 degrees C. However, freezing at -10.9 degrees C, resulting in 67% ice, was lethal. A survey of possible cryoprotectants revealed a 2- to 3-fold increase in glucose content of liver and blood and a 3-fold increase in blood glycerol in response to freezing. Although quantitatively low, these responses by spring turtles strongly indicate that these may be the winter-active cryoprotectants. The total amino acid pool of blood also increased 2.25-fold in freezing-exposed turtles, and taurine accounted for 52% of the increase. Most organs accumulated high concentrations of lactate during freezing, a response to the ischemic state imposed by extracellular freezing. Changes in glycogen phosphorylase activity and levels of glucose 6-phosphate and fructose 2,6-bisphosphate were also consistent with a dependence on anaerobic glycolysis during freezing. Studies of the molecular mechanisms of natural freeze tolerance in these turtles may identify protective strategies that can be used in mammalian organ cryopreservation technology.

Storey, K B; Storey, J M; Brooks, S P; Churchill, T A; Brooks, R J

1988-01-01

202

High nitrous oxide emissions during winter from boreal agricultural soils  

NASA Astrophysics Data System (ADS)

The concern of nitrous oxide (N_2O) emissions during winter has recently arisen. Winter N_2O emissions in the boreal region accounting 10 to 90% of the annual emissions have been reported. High N_2O emissions during winter have been related to the freezing-thawing cycles. We measured the annual N_2O emissions, including winter, from different agricultural soils (pasture on mineral soil, organic agricultural soil, afforested organic agricultural soils and uncultivated organic agricultural soils) in Finland. N_2O fluxes were determined with chamber method during the snow-free period and by measuring the N_2O concentration gradients in the snowpack during the winter. The gas samples were analysed with a gas chromatograph (EC detector). N_2O emissions were at their lowest in the autumn and increased after the topsoil was frozen. The results show high N_2O emissions during periods with a permanent snow cover and when the air temperature is below 0^oC. The wintertime emissions were even larger than those during non-frozen season. Surprisingly, when the air temperature was three weeks between 20 and 35^oC, N_2O emissions remained at constantly high level. Therefore, we suggest that these high N_2O winter emissions are not strictly connected to the freezing-thawing cycles or changes in the air temperature below 0^oC.

Maljanen, M.; Hytönen, J.; Yli-Petäys, M.; Laine, J.; Virkajärvi, P.; Järvenranta, K.; Martikainen, P. J.

2003-04-01

203

Reducing winter injury in blackberries  

Technology Transfer Automated Retrieval System (TEKTRAN)

We evaluated the combination of primocane training and cane positioning techniques using a rotatable cross-arm (RCA) trellis system and covering plants in winter to protect buds and canes from freezing temperatures in ‘Apache’, ‘Boysenberry’, ‘Siskiyou’, and ‘Triple Crown’ blackberry. After tying p...

204

International scientists on nuclear winter  

Microsoft Academic Search

A report by the International Council of Scientific Unions (ICSU) leads new support to the warning of extreme climatic disruptions that would follow a nuclear war. The two-volume report does not deal explicitly with public policy questions, but focuses on scientific knowledge of physical effects and biological responses. The author reviews studies made since the warning of a nuclear winter

Malone

1985-01-01

205

EPS Workshop on Nuclear Winters  

Microsoft Academic Search

This workshop was held in Geneva in October 1986 and was attended by invited delegates from both East (14) and West (13), members of the ACPS (5) and the President. Relevant disciplines as well as Physics were represented which lead to comprehensive discussions.The factors which have a bearing on the probabilities of a nuclear winter were reviewed using the SCOPE-ENUWAR

D H Parkinson

1988-01-01

206

Select bibliography on nuclear winter  

Microsoft Academic Search

A 1982 article by P.J. Crutzen and J.W. Birks first suggested that smoke from wildland and urban fires could have a significant impact on the atmosphere. The theory of nuclear winter was first presented at the World after Nuclear War conference held in 1983. Following the conference, articles describing the potential climatic and biological consequences of a global nuclear exchange

1987-01-01

207

EPS Workshop on Nuclear Winters  

Microsoft Academic Search

This workshop was held in Geneva in October 1986 and was attended by invited delegates from both East (14) and West (13), members of the ACPS (5) and the President. Relevant disciplines as well as Physics were represented which lead to comprehensive discussions. The factors which have a bearing on the probabilities of a nuclear winter were reviewed using the

D. H. Parkinson

1988-01-01

208

Learning through a Winter's Tale  

ERIC Educational Resources Information Center

|In this article, the author shares her experience during the final semester of Year 11 Theatre Studies when she performed a monologue about Hermione from "The Winter's Tale". This experience was extremely significant to her because it nearly made her lose faith in one of the most important parts of her life, drama. She believes this experience,…

Vidotto, Kristie

2010-01-01

209

Nuclear Winter Attracts Additional Scrutiny  

Microsoft Academic Search

Prodded by the Natural Resources Defense Council, Congress has asked the Pentagon to provide what amounts to an environmental impact statement on the potential for nuclear weapons explosions to create enough soot and dust to cause a nuclear winter. The request has implications for arms control and civil defense as well as for weapons procurement and deployment. Little attention was

R. Jeffrey Smith

1984-01-01

210

Nuclear Winter: The Continuing Debate.  

National Technical Information Service (NTIS)

This essay examines the debate over the climatic consequences of global nuclear war as related in the so-called Nuclear Winter hypothesis. the review examines the major components of the theory and traces development of the scientific knowledge leading to...

A. V. Nida

1987-01-01

211

Research and accountability in the 2010 Olympic and Paralympic Winter Games  

Microsoft Academic Search

The 2010 Olympic and Paralympic Winter Games are becoming a turning point in both the Canadian sport system (e.g., increased focus on amateur (winter) sports, increased cooperation between actors in the system) and the Olympic Movement (e.g., presentation of the Games' Multi Party Agreement, MPA, signed in the Bid phase, as a good tool for focusing and coordinating government involvement

Milena Parent; Rod Windover

2008-01-01

212

Movements of wintering Dunlin Calidris alpina and changing habitat availability in an agricultural wetland landscape  

USGS Publications Warehouse

Few studies have assessed how the dynamics of wetland bird movements relate to changing resource availability, particularly at more than one spatial scale. Within western Oregon's Williamette Valley, we examined winter resident Dunlin Calidris alpina movements in relation to a decrease in availability of preferred shorebird foraging habitat from early to late winter of 1999-2000. By tracking movements of 15 (early winter) and 12 (late winter) radiomarked individuals, we calculated home ranges and characterized presence/absence of a preference for shorebird foraging habitat during each winter period. Between periods, we compared: (1) percentage of shorebird habitat in home ranges to its availability in the landscape (regional preference), (2) percentage of radio locations in shorebird habitat to its availability within home ranges (local preference) and (3) relative use of roost sites. Concurrent with a 75% decrease in available shorebird habitat from early to late winter, average home range sizes increased by a factor of 3.8. At a regional scale, home ranges in early winter included a significantly greater percentage of shorebird foraging habitat than was available in the wider landscape. However, by late winter, the percent of shorebird habitat in home ranges did not match availability in the landscape. At the local scale, for both winter periods Dunlin were located in shorebird foraging habitat more often than expected given availability of habitat within home ranges [Correction added after online pub-lication 23 May 2008: sentence amended]. An increase in the number of roosts used from early to late winter implies possible reliance on additional sites in late winter for foraging opportunities. Results suggest that wet, unvegetated habitat is sought by Dunlin throughout winter, but individuals could not select home ranges in late winter that fully compensated for seasonal loss of habitat. ?? 2008 The Authors.

Taft, O. W.; Sanzenbacher, P. M.; Haig, S. M.

2008-01-01

213

Unusual Southern Hemisphere Stratosphere Winter of 2002.  

National Technical Information Service (NTIS)

The southern hemisphere stratospheric winter of 2002 was the most unusual winter yet observed in the southern hemisphere climate record. Temperatures near the edge of the Antarctic polar vortex were considerably warmer than normal over the entire course o...

P. A. Newman E. R. Nash

2003-01-01

214

RETRACTED ARTICLE: Space and time distributions of major winter storms in the United States  

Microsoft Academic Search

Winter storms are a major weather problem in the United States and their losses have been rapidly increasing. A total of 202\\u000a catastrophic winter storms involving ice storms, blizzards, and snowstorms, each causing >$5 million in damages, occurred\\u000a during 1949–2003, and their losses totaled $35.2 billion (2003 dollars). Catastrophic winter storms occurred in most parts\\u000a of the contiguous United States, but were

2008-01-01

215

Winter in a Svalbard Fiord Ecosystem  

Microsoft Academic Search

Data pertaining to the characteristics of an arctic fiord in winter were collected at the Polish Arctic Station situated in Hornsund at 77ON, 15OE on Svalbard. Winter in the fiord was defined in terms of climate (November-May), hydrology (January-March) and biology (November-March). The characteristic phenomena of winter in the fiord include a winter drop in the yearly biomass maximum to

J. M. WESLAWSKI; S. KWASNIEWSKI; J. WIKTOR

1991-01-01

216

Britannica Sporting Record: The Winter Games  

NSDL National Science Digital Library

Encyclopaedia Britannica's Olympic Winter Games site offers detailed Olympic information and history. Offerings include an overview of the Olympic movement, histories of each of the past seventeen Olympic Winter Games, articles about the events included in the Winter Games, biographies of past competitors, and a searchable Olympic Record database. This well-researched site provides an interesting backdrop for this year's Winter Games in Nagano, Japan.

Encyclopaedia Britannica, Inc.

1998-01-01

217

On the simulation of winter precipitation types  

Microsoft Academic Search

Winter storms produce major problems for society, and the key responsible factor is often the varying types of precipitation. The objective of this study is to better understand the formation of different types of winter precipitation (freezing rain, ice pellets, snow, slush, wet snow and refrozen wet snow) within the varying and interacting environmental conditions in many winter storms. To

J. M. Thériault; R. E. Stewart; J. A Milbrandt; M. K. Yau

2006-01-01

218

Glycogen, not dehydration or lipids, limits winter survival of side-blotched lizards (Uta stansburiana).  

PubMed

Climate change is causing winters to become milder (less cold and shorter). Recent studies of overwintering ectotherms have suggested that warmer winters increase metabolism and decrease winter survival and subsequent fecundity. Energetic constraints (insufficient energy stores) have been hypothesized as the cause of winter mortality but have not been tested explicitly. Thus, alternative sources of mortality, such as winter dehydration, cannot be ruled out. By employing an experimental design that compared the energetics and water content of lizards that died naturally during laboratory winter with those that survived up to the same point but were then sacrificed, we attempt to distinguish among multiple possible causes of mortality. We test the hypothesis that mortality is caused by insufficient energy stores in the liver, abdominal fat bodies, tail or carcass or through excessive water loss. We found that lizards that died naturally had marginally greater mass loss, lower water content, and less liver glycogen remaining than living animals sampled at the same time. Periodically moistening air during winter reduced water loss, but this did not affect survival, calling into question dehydration as a cause of death. Rather, our results implicate energy limitations in the form of liver glycogen, but not lipids, as the primary cause of mortality in overwintering lizards. When viewed through a lens of changing climates, our results suggest that if milder winters increase the metabolic rate of overwintering ectotherms, individuals may experience greater energetic demands. Increased energy use during winter may subsequently limit individual survival and possibly even impact population persistence. PMID:22875774

Zani, Peter A; Irwin, Jason T; Rollyson, Mary E; Counihan, Jessica L; Healas, Sara D; Lloyd, Emily K; Kojanis, Lee C; Fried, Bernard; Sherma, Joseph

2012-09-01

219

Nuclear Winter PowerPoint  

NSDL National Science Digital Library

This one-hour slide presentation on the theory of nuclear winter discusses the potentially catastrophic effects that large-scale nuclear warfare might have on Earth's atmosphere and climate. Topics include the nature of the world's current nuclear arsenal, climate model results, phenomena that might produce analogous impacts (forest fires, city fires, volcanic eruptions, extinction of the dinosaurs), impacts on humans, and policy implications.

Robock, Alan

2005-07-04

220

Inverse simulation of snowmelt runoff and snow cover area using the energy balance-based distributed snowmelt model (WEB-DHM-S) for the correction of basin-scale snowfall  

NASA Astrophysics Data System (ADS)

In this study, a method has been established that explicitly corrects the basin-scale snowfall amount through the inverse simulation of snowmelt runoff and snow cover area (SCA) with the use of the multilayer energy balance based distributed snowmelt model (WEB-DHM-S). The evaluation indices, obtained from the pixel-to-pixel analysis between the simulated SCA and the SCA derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard the Terra Satellite, and from the statistical analysis between the simulated and observed snowmelt runoff, were used to define the threshold criteria for the minimization of bias/maximization of accuracy following the calibration of the orography-dependent snowfall correction factor (SCF). The method was applied at Yagisawa basin (167 km2) of the Upper Tone River of Japan. The model was run at hourly time step at 500 m grid from November 2000 to November 2004. Two types of precipitation (observed rain gauge, called AMeDAS and Radar data adjusted with rain gauge observations, called Radar-AMeDAS) inputs were corrected with this approach since both dataset highly underestimated the snowmelt runoff due to large underestimation of snowfall. The basin average SCF was estimated at 1.87 times for AMeDAS and at 3.77 times for Radar-AMeDAS precipitation, for which Nash Efficiency was greater than 0.80, and the overall accuracy of SCA simulation between the MODIS and the model was about 91%. The method established in this study is simple and robust, and can be applied to any snow-fed river basin to obtain a reliable SCF. Furthermore, this approach could be applicable in correcting the snowfall from reanalysis products and atmospheric model outputs which could be very supportive in the climate and land surface hydrological researches.

Shrestha, M.; Wang, L.; Koike, T.; Tsutsui, H.; Xue, Y.; Hirabayashi, Y.

2012-04-01

221

Daily movements of female mallards wintering in Southwestern Louisiana  

USGS Publications Warehouse

Understanding daily movements of waterfowl is crucial to management of winter habitats, especially along the Gulf Coast where hunting pressure is high. Radio-telemetry was used to investigate movements of female Mallards (Anas platyrchychos) wintering in southwestern Louisiana. Movement distances were analyzed from 2,455 paired locations (diurnal and nocturnal) of 126 Mallards during winters 2004-2005 and 2005-2006 to assess effects of winter, female age, areas closed (Lacassine National Wildlife Refuge [LAC], Cameron Prairie National Wildlife Refuge [CAM], Amoco Pool [AMOCO] or open to hunting [OPEN]), and habitat type, including all interactions. Movement distances from the various land management categories were not consistent by age, date, or by winter. Flight distances from LAC increased with date, whereas those from CAM and OPEN did not vary significantly by date. Female Mallards moved short distances between diurnal and nocturnal sites (ranging from 3.1 to 15.0 km by land management category), suggesting that they are able to meet their daily energy requirements within a smaller area than Northern Pintails (Anas acuta, hereafter Pintails), and thus minimize transit energy costs.

Link, P. T.; Afton, A. D.; Cox, Jr. , R. R.; Davis, B. E.

2011-01-01

222

Winter pairs of ruddy shelducks at Lashihai Lake, southwest China.  

PubMed

It has been suggested that pairing behavior during winter in migratory ducks represents a trade-off between costs (defense of the female) and benefits (early access to females). To investigate the benefits and costs for both sexes in wintering pairs of ruddy shelducks (Tadorna ferruginea), we compared time budgets for paired males and females, and surveyed the sex ratio of the birds wintering at Lashihai Lake, southwest China. The behavior of the paired ruddy shelducks was monitored for 5 activity types: feeding, resting (including sleeping), preening, drinking and warning. Feeding was the most dominant activity. The feeding time of both sexes increased as the winter season progressed. However, the paired females always spent significantly more time feeding and less time warning than the paired males. Paired ruddy shelducks had access to better feeding grounds than unpaired individuals, resulting in a food benefit for paired individuals over single individuals. Because the sex ratio of the wintering population was strongly male biased (M:F = 1.44:1.00), the paired male also gained the benefit of accessing a female in advance of the breeding season. PMID:23621471

Quan, Ruichang; Cui, Liangwei

2012-10-31

223

Quantifying production potentials of winter wheat in the North China Plain  

Microsoft Academic Search

The North China Plain (NCP) is one of the major winter wheat (Triticum aestivum L.) producing areas in China. Current wheat yields in the NCP stabilize around 5Mgha?1 while the demand for wheat in China is growing due to the increase in population and the change in diet. Since options for area expansion of winter wheat are limited, the production

Dingrong Wu; Qiang Yu; Changhe Lu; Huib Hengsdijk

2006-01-01

224

Quantifying production potential of winter wheat in the North China Plain  

Microsoft Academic Search

The North China Plain (NCP) is one of the major winter wheat (Triticum aestivum L.) producing areas in China. Current wheat yields in the NCP stabilize around 5 Mg ha¿1 while the demand for wheat in China is growing due to the increase in population and the change in diet. Since options for area expansion of winter wheat are limited,

D. Wu; Q. Yu; C. Lu; H. Hengsdijk

2006-01-01

225

Winter climate change: Ice encapsulation at mild subfreezing temperatures kills freeze-tolerant lichens  

Microsoft Academic Search

While it has been widely proven that many lichens are extremely freeze-tolerant in the dry state, little is known about how moist lichens respond to freezing under oxic and anoxic conditions. In circumpolar areas where lichens are an important component of boreal and Arctic ecosystems, winter climate is changing, leading to increased frequency of winter thaw and ground-icing events. It

Jarle W. Bjerke

2011-01-01

226

Plasticity in body temperature and metabolic capacity sustains winter activity in a small endotherm ( Rattus fuscipes)  

Microsoft Academic Search

Small mammals that remain active throughout the year at a constant body temperature have a much greater energy and food requirement in winter. Lower body temperatures in winter may offset the increased energetic cost of remaining active in the cold, if cellular metabolism is not constrained by a negative thermodynamic effect. We aimed to determine whether variable body temperatures can

Elsa J. Glanville; Frank Seebacher

2010-01-01

227

A description of water types on the Mackenzie shelf of the Beaufort Sea during winter  

Microsoft Academic Search

For a number of years during the 1980s, observations of the physical and chemical properties of seawater in the southeastern Beaufort Sea have been acquired in late winter. The most complete data set, from 1987, has been used in a comparison of winter and summer [Macdonald et al., 1989] water properties in the area. Most obvious is an increase in

R. M. Moore; H. Melling; K. R. Thompson

1992-01-01

228

Evidence of a Causal Role of Winter Virus Infection during Infancy in Early Childhood Asthma  

Microsoft Academic Search

Rationale: Bronchiolitis during infancy is associated with an increased risk of childhood asthma. Whether winter viral infections cause asthma or are a manifestation of a predisposition to asthma de- velopment is unknown. Objectives: To study the relationship of winter virus infection during infancy and the development of childhood asthma. Methods: We studied over 95,000 infants born between 1995 and 2000

Pingsheng Wu; William D. Dupont; Marie R. Griffin; Kecia N. Carroll; Edward F. Mitchel; Tebeb Gebretsadik; Tina V. Hartert

2008-01-01

229

Prickly Pear Cactus Responses to Summer and Winter Fires  

Microsoft Academic Search

Prescribed fire is used to reduce size and density of prickly pear cactus (Opuntia spp.) in many rangeland ecosystems. However, effects of dormant season fires (i.e., winter fires) are inconsistent. Thus, there is increasing interest in use of growing season (summer) fires. Our objective was to evaluate effects of fire season and fire intensity on mortality and individual plant (i.e.,

R. James Ansley; Michael J. Castellano

2007-01-01

230

Impacts of climate change on winter wheat production in China  

Microsoft Academic Search

Climate is changing due to increasing concentration of greenhouse gases, affecting many economic sectors, e.g. agriculture and forestry. Agriculture is a basic sector, especially to China with the most population. Wheat is the second most important staple crops in China. Therefore, assessment of the impacts of climate change on winter wheat is essential for policy maker and wheat producers for

Zhan Tian; Zhiqiang Gao; Yinlong Xu; Hua Chen

2005-01-01

231

Registration of 'NI04421' hard red winter wheat  

Technology Transfer Automated Retrieval System (TEKTRAN)

Water for irrigation is a major constraint in the Great Plains and it is expected that the proportion of irrigated crop land to grow irrigated wheat will increase to conserve irrigation water. 'NI04421' (Reg. No. PI 659690) hard red winter wheat (Triticum aestivum L.) was developed cooperatively by...

232

Record of winter monsoon strength.  

PubMed

The Asian summer monsoon has been precisely reconstructed from the high-resolution record from the speleothem, but reconstruction of the Asian winter monsoon is less satisfactory. Yancheva et al. provide such a reconstruction for the last 16,000 years from the titanium (Ti) content of the sediments of Lake Huguang Maar in coastal South China. However, we argue that the Ti is likely to have come mainly from the catchment and so the Ti content may instead be related to the hydrology of the lake. PMID:18004318

Zhou, Houyun; Guan, Huazheng; Chi, Baoquan

2007-11-15

233

The influence of the Arctic Oscillation on winter temperatures in Iran  

NASA Astrophysics Data System (ADS)

The impact of the Arctic Oscillation (AO) on the winter surface air temperature (SAT) over Iran is demonstrated. Winter SAT data for 50 years (1951 2000) are analyzed for the negative and the positive AO phases. Using the Median Sequential Correlation Analysis (MSCA) technique it is shown that the winter SAT is negatively correlated to the winter AO index for most parts of Iran. The winter AO index accounts for about 14% to 46% of the winter SAT variance. The positive (negative) SAT anomaly is found to be associated with the onset of the negative (positive) phase. The overall probability of below long-term mean temperature during the positive and the negative phases are estimated to be around 70% and 25%, respectively. For the negative phase, westerly winds that originate from the warm Atlantic regions increase over Iran and consequently positive temperature anomalies are found across the country. The positive AO phase is accompanied by northerly winds that allow continental polar and arctic air masses to move into Iran, producing below normal temperatures. The summer AO is found to explain about 25 32% of the winter SAT variance in Iran. The reason for this is explained by the significant correlation (+0.38) between the summer and the following winter AO indices. These results indicate that the summer climate is linked to changes in atmospheric circulation which persist through to the following autumn and winter.

Ghasemi, A. R.; Khalili, D.

2006-07-01

234

Controls on winter ecosystem respiration at mid- and high-latitudes  

NASA Astrophysics Data System (ADS)

Winter CO2 fluxes represent an important component of the annual carbon budget in northern ecosystems. Understanding winter respiration processes and their responses to climate change is also central to our ability to assess terrestrial carbon cycle and climate feedbacks in the future. The factors influencing the spatial and temporal pattern of winter respiration (RECO) of northern ecosystems are poorly understood. For this reason, we analyzed eddy covariance flux data sets from 57 ecosystem sites ranging from ~35° N to ~70° N. Deciduous forests carry the highest winter RECO ratios (9.7-10.5 g C m-2 d-1), when winter is defined as the period during which air temperature remained below 0 °C. By contrast, wetland ecosystems had the lowest winter RECO (2.1-2.3 g C m-2 d-1). Evergreen needle-leaved forests, grasslands and croplands were characterized by intermediate winter RECO values of 7.4-7.9 g C m-2 d-1, 5.8-6.0 g C m-2 d-1, and 5.2-5.3 g C m-2 d-1, respectively. Cross site analysis showed that winter air or soil temperature, and the seasonal amplitude of the leaf area index inferred from satellite observation, which is a proxy for the amount of litter available for RECO in the subsequent winter, are the two main factors determining spatial pattern of daily mean winter RECO. Together, these two factors can explain 71% (Tair, ?LAI) or 69% (Tsoil, ?LAI) of the spatial variance of winter RECO across the 57 sites. The spatial temperature sensitivity of daily winter RECO was determined empirically by fitting an Arrhenius relationship to the data. The activation energy parameter of this relationship was found to decrease at increasing soil temperature at a rate of 83.1 KJ ° C-1 (r = -0.32, p < 0.05), which implies a possible dampening of the increase in winter RECO due to global warming. The interannual variability of winter RECO is better explained by soil temperature than by air temperature, likely due to the insulating effects of snow cover. The increase in winter RECO with a 1 °C warming based calculated from the spatial analysis was almost that double that calculated from the temporal analysis. Thus, models that calculate the effects of warming on RECO based only on spatial analyses could be over-estimating the impact.

Wang, T.; Ciais, P.; Piao, S.; Ottle, C.; Brender, P.; Maignan, F.; Arain, A.; Gianelle, D.; Gu, L.; Lafleur, P.; Laurila, T.; Margolis, H.; Montagnani, L.; Moors, E.; Nobuko, S.; Vesala, T.; Wohlfahrt, G.; Reichstein, M.; Migliavacca, M.; Ammann, C.; Aubinet, M.; Barr, A.; Bernacchi, C.; Bernhofer, C.; Black, T.; Davis, K.; Dellwik, E.; Dragoni, D.; Don, A.; Flanagan, L.; Foken, T.; Granier, A.; Hadley, J.; Hirata, R.; Hollinger, D.; Kato, T.; Kutsch, W.; Marek, M.; Matamala, R.; Matteucci, G.; Meyers, T.; Monson, R.; Munger, J.; Oechel, W.; Paw U, K. T.; Rebmann, C.; Tuba, Z.; Valentini, R.; Varlagin, A.; Verma, S.

2010-09-01

235

Winter warming from large volcanic eruptions  

SciTech Connect

An examination of the Northern Hemisphere winter surface temperature patterns after the 12 largest volcanic eruptions from 1883-1992 shows warming over Eurasia and North America and cooling over the Middle East which are significant at the 95 percent level. This pattern is found in the first winter after tropical eruptions, in the first or second winter after midlatitude eruptions, and in the second winter after high latitude eruptions. The effects are independent of the hemisphere of the volcanoes. An enhanced zonal wind driven by heating of the tropical stratosphere by the volcanic aerosols is responsible for the regions of warming, while the cooling is caused by blocking of incoming sunlight.

Robock, A.; Mao, J.

1992-01-01

236

An assessment of the potential and impacts of winter water banking in the Sokh aquifer, Central Asia  

Microsoft Academic Search

The dynamics of artificial recharge of winter surface flows coupled with increased summer groundwater use for irrigation in\\u000a the Sokh aquifer (Central Asia) have been investigated. Water release patterns from the giant Toktogul reservoir have changed,\\u000a as priority is now given to hydropower generation in winter in Kyrgyzstan. Winter flows have increased and summer releases\\u000a have declined, but the Syr

Inna Gracheva; Akmal Karimov; Hugh Turral; F. Miryusupov

2009-01-01

237

The History of Winter and the Global Snowflake Network, Engaging Teachers and Students in Science Field Research in Snow and Ice  

NASA Astrophysics Data System (ADS)

A weeklong Professional development/"Teacher as scientist" Cryosphere science training camp held annually in February in Lake Placid, NY, the History of Winter program (HOW) has been serving teachers in the NASA Goddard Space Flight Center service area since 2000. Currently, HOW participants include university faculty interested in enhancing their pre-service science education programs, in-service teachers and pre-service education students. HOW utilizes a stratified professional development approach to science content mastery and delivery while involving participants in scientific field research. Each year program components and resources are added to HOW to provide continued, sustainable interest in the program and to support participants as they continue their HOW experience. An offshoot of the HOW Program, the Global Snowflake Network (GSN) launched in the winter of 2006 engages an international audience including both formal and informal education groups. The goal is to provide an interactive online data resource in science and education for the characterization of snowfall and related weather systems. The Global Snowflake Network has been accepted as an education outreach proposal for the International Polar Year. Collaborations with other agencies and universities also with IPY-accepted proposals are now underway. HOW and the GSN are endorsed by the NASA Goddard Education Office and many of the Goddard Snow and Ice scientists. Together these programs offer a unique, sustainable, and proven outreach for the Cryosphere research program.

Bender, K. J.; Wasilewski, P. J.; Gabrys, R. E.

2006-05-01

238

Mass dynamics of wintering Pacific Black Brant: Body, adipose tissue, organ, and muscle masses vary with location  

USGS Publications Warehouse

We compared body size and mass of the whole body, organs, adipose tissue, and muscles of adult Pacific Black Brant (Branta bernicla nigricans (Lawrence, 1846)) collected concurrently in Alaska and Baja California during the fall, winter, and spring of 2002-2003. Head and tarsal lengths of males were similar between sites and slightly larger for females in Alaska than in Baja California. Brant appear to operate under similar physiological bounds, but patterns of nutrient allocation differ between sites. Birds wintering in Alaska lost similar amounts of adipose tissue during early winter as birds in Baja California gained during late winter before migration. Masses of the body, adipose tissue, and flight muscles during mid-winter were similar between sites. Seasonal adipose tissue deposition may, therefore, equally favor winter residency or long-distance migration. Gonad and liver masses increased in late winter for birds in Alaska but not for those in Baja California, suggesting birds wintering in Baja may delay reproductive development in favor of allocating reserves needed for migration. Phenotypic flexibility allows Brant to use widely divergent wintering sites. The wintering location of Brant likely depends more upon changes in environmental conditions and food availability, than upon physiological differences between the two wintering populations. ?? 2007 NRC.

Mason, D. D.; Barboza, P. S.; Ward, D. H.

2007-01-01

239

Winter Biological Processes Could Help Convert Arctic Tundra to Shrubland  

NSDL National Science Digital Library

This peer-reviewed article from BioScience investigates the change from tundra to shrubland in the arctic. In arctic Alaska, air temperatures have warmed 0.5 degrees Celsius (C) per decade for the past 30 years, with most of the warming coming in winter. Over the same period, shrub abundance has increased, perhaps a harbinger of a conversion of tundra to shrubland. Evidence suggests that winter biological processes are contributing to this conversion through a positive feedback that involves the snow-holding capacity of shrubs, the insulating properties of snow, a soil layer that has a high water content because it overlies nearly impermeable permafrost, and hardy microbes that can maintain metabolic activity at temperatures of −6C or lower. Increasing shrub abundance leads to deeper snow, which promotes higher winter soil temperatures, greater microbial activity, and more plant-available nitrogen. High levels of soil nitrogen favor shrub growth the following summer. With climate models predicting continued warming, large areas of tundra could become converted to shrubland, with winter processes like those described here possibly playing a critical role.

MATTHEW STURM, JOSH SCHIMEL, GARY MICHAELSON, JEFFREY M. WELKER, STEVEN F. OBERBAUER, GLEN E. LISTON, JACE FAHNESTOCK, and VLADIMIR E. ROMANOVSKY (;)

2005-01-01

240

Winter Olympics Physics and Biomechanics  

NSDL National Science Digital Library

Many Winter Olympic sports are greatly dependent on technique, engineering, and/or gravity. For example, during luge, while gravity is accelerating the sled up to 80 mph down the track, the slider must use good technique to steer the sled and minimize air resistance. To excel in these type of sports, it is helpful to have a full appreciation of physics and biomechanics. Physics is a broad field which includes mechanics, electricity, magnetism, optics, etc., and biomechanics is the study of the mechanics of living systems. In the module we will use the sports of luge and figure skating to teach you four basic mechanical concepts: linear kinematics, linear dynamics, projectile motion, and conservation of angular momentum. In addition, we have developed a glossary which defines and illustrates all the physics terminology you will need to complete this module.

241

International scientists on nuclear winter  

SciTech Connect

A report by the International Council of Scientific Unions (ICSU) leads new support to the warning of extreme climatic disruptions that would follow a nuclear war. The two-volume report does not deal explicitly with public policy questions, but focuses on scientific knowledge of physical effects and biological responses. The author reviews studies made since the warning of a nuclear winter began in 1982, and evaluates the new report. He finds the message of the report to be a clear warning that a major nuclear war would threaten the entire world. He hopes it will be a catalyst to world opinion in the same way that the public responded to the incident of radioactive fallout striking a Japanese fishing vessel in 1954.

Malone, T.F.

1985-12-01

242

PLCO News, Fall/Winter 1998  

Cancer.gov

PLCO News, Fall/Winter 1998 Volume 1, Number 2 ----- Fall/Winter 1998 TABLE OF CONTENTS Notes from theNCI's PLCO Project Office Meet John GohaganMeet Phil Prorok From Lab to Life Possible prostate cancer prevention with vitamin E and selenium

243

Does cold winter weather produce depressive symptoms?  

NASA Astrophysics Data System (ADS)

To examine whether harsh winter weather is associated with depressive symptoms, 45 healthy subjects from Minnesota were compared to 42 subjects from California near the end of the winter season. No differences in the prevalence of depressive symptoms were found between the two groups.

Garvey, Michael J.; Goodes, Mike; Furlong, Candy; Tollefson, Gary D.

1988-06-01

244

Nuclear winter: The evidence and the risks  

Microsoft Academic Search

Global concern over nuclear extinction, centered on the holocaust itself, now has turned to the more terrifying consequences of a post-war nuclear winter: ''the long-term effects - destruction of the environment, spread of epidemic diseases, contamination by radioactivity, and ... collapse of agriculture-(that) would spread famine and death to every country.'' Nuclear Winter, the latest in a series of studies

Greene

1985-01-01

245

The Wintering of Uredomycelia of Wheat Rust.  

National Technical Information Service (NTIS)

Mycelia of the causative agent of stem rust in wheat are not killed by low air temperatures in the winter, except when there is no snow covering. With a snow covering of 17-20 cm, mycelia in the plants can pass the winter and create local, early sources o...

L. A. Smirnova Z. I. Bessneltsev Z. P. Shinkarev

1969-01-01

246

Disturbance to wintering western snowy plovers  

Microsoft Academic Search

In order to better understand the nature of disturbances to wintering snowy plovers, I observed snowy plovers and activities that might disturb them at a beach near Devereux Slough in Santa Barbara, California, USA. Disturbance (activity that caused plovers to move or fly) to wintering populations of threatened western snowy plovers was 16 times higher at a public beach than

Kevin D. Lafferty

2001-01-01

247

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

248

Mars Odyssey: Water Ice-Winter Observations  

NSDL National Science Digital Library

NASAs Mars Odyssey detected water ice in the northern hemisphere. During the winter months, the icy soil is covered by a thick layer of carbon dioxide (dry ice) frost obscuring the water ice signature.This animation is match-framed to #2778 and #2780. It shows the areas of ice during a martian winter.

Kekesi, Alex; Shirah, Greg; Zuber, Maria; Smith, David; Neumann, Gregory

2003-07-03

249

Winter huddling groups in the striped mouse  

Microsoft Academic Search

Huddling is a strategy to avoid heat loss and thus save energy and is often observed in birds and rodents, which, because of their small body size, are prone to relatively high heat loss. Huddling might thus explain group-living in some cases, such as the winter huddling groups described for several northern hemisphere rodents. Here we describe winter hud- dling

C. Schradin; M. Schubert; N. Pillay

2006-01-01

250

Nuclear Winter: Scientists in the Political Arena  

NASA Astrophysics Data System (ADS)

The nuclear winter phenomenon is used to illustrate the many paths by which scientific advice reaches decision makers in the United States government. Because the Reagan administration was hostile to the strategic policy that the scientific discovery seemed to demand, the leading proponent of nuclear winter, Carl Sagan, used his formidable talent for popularization to reach a larger audience.

Badash, Lawrence

2001-03-01

251

Nuclear winter: Asymmetrical problems and unilateral solutions  

Microsoft Academic Search

Nuclear winter creates a dilemma for policymakers. Awareness of that dilemma may not be new, however. Long before the phrase nuclear winter became popular, policymakers may well have been aware of the possibility that the indirect effects of a nuclear exchange could be more damaging than the direct effects. Nevertheless, the more widespread public awareness of such a possibility deepens

Reule

1986-01-01

252

Nuclear Winter: Scientists in the Political Arena  

Microsoft Academic Search

The nuclear winter phenomenon is used to illustrate the many paths by which scientific advice reaches decision makers in the United States government. Because the Reagan administration was hostile to the strategic policy that the scientific discovery seemed to demand, the leading proponent of nuclear winter, Carl Sagan, used his formidable talent for popularization to reach a larger audience.

Lawrence Badash

2001-01-01

253

PLCO News, Fall/Winter 1998  

Cancer.gov

PLCO News, Fall/Winter 1998 Volume 1, Number 2 ----- Fall/Winter 1998 Cancer Information Center If you have a question about cancer you can call and speak with a trained specialist at NCI's Cancer Information Service (CIS). The CIS operates a toll-free,

254

PLCO News, Fall/Winter 1998  

Cancer.gov

PLCO News, Fall/Winter 1998 Volume 1, Number 2 ----- Fall/Winter 1998 Trial Update Enrollment goal: 148,000 Total enrollment (as of September 30, 1998): 111,515 Men enrolled: 58,283 Women enrolled: 53,232 Number of people enrolled

255

What do we know about winter active ground beetles (Coleoptera, Carabidae) in Central and Northern Europe?  

PubMed Central

Abstract This paper summarizes the current knowledge on winter active Carabidae in Central and Northern Europe. In total 73 winter active species are listed, based on literature and own observations. Ground beetles are among the three most numerous Coleoptera families active during the autumn to spring period. The winter community of Carabidae is composed both of larvae (mainly autumn breeding species) and adults, as well as of epigeic species and those inhabiting tree trunks. Supranivean fauna is characterized by lower species diversity than the subnivean fauna. The activity of ground beetles decreases in late autumn, is lowest during mid-winter and increases in early spring. Carabidae are noted as an important food source in the diet of insectivorous mammals. They are also predators, hunting small winter active invertebrates.

Jaskula, Radomir; Soszynska-Maj, Agnieszka

2011-01-01

256

Density- and Size-Dependent Winter Mortality and Growth of Late Chaoborus flavicans Larvae  

PubMed Central

Winter processes such as overwinter survival and growth of individuals can have wide-ranging consequences for population dynamics and communities within and across seasons. In freshwater organisms winter processes have been mainly studied in fish despite that invertebrates also have substantial impacts on lake and pond food webs. One of the major invertebrate consumers in lake and ponds is the planktonic larvae of the dipteran insect Chaoborus spec. However, while much is known about Chaoborus feeding ecology, behaviour and structuring role in food webs, its winter ecology and how it affects its populations are poorly understood. Here size- and density-dependent winter mortality and body growth of late Chaoborus flavicans larvae were quantified over naturally occurring size and density ranges in autumn and under natural winter conditions using two field enclosure experiments. Winter mortality increased with autumn density but decreased with autumn body size while winter growth rates decreased with autumn density and body sizes. There was also a density- and size-independent background mortality component. The proportion of pupae found in spring decreased strongly and exponentially with autumn density. These results may explain the commonly observed univoltine life cycle and multi-annual density fluctuations in northern Chaoborus populations. They further demonstrate the relevance of winter processes and conditions for freshwater invertebrates and ecosystems.

Schroder, Arne

2013-01-01

257

Density- and Size-Dependent Winter Mortality and Growth of Late Chaoborus flavicans Larvae.  

PubMed

Winter processes such as overwinter survival and growth of individuals can have wide-ranging consequences for population dynamics and communities within and across seasons. In freshwater organisms winter processes have been mainly studied in fish despite that invertebrates also have substantial impacts on lake and pond food webs. One of the major invertebrate consumers in lake and ponds is the planktonic larvae of the dipteran insect Chaoborus spec. However, while much is known about Chaoborus feeding ecology, behaviour and structuring role in food webs, its winter ecology and how it affects its populations are poorly understood. Here size- and density-dependent winter mortality and body growth of late Chaoborus flavicans larvae were quantified over naturally occurring size and density ranges in autumn and under natural winter conditions using two field enclosure experiments. Winter mortality increased with autumn density but decreased with autumn body size while winter growth rates decreased with autumn density and body sizes. There was also a density- and size-independent background mortality component. The proportion of pupae found in spring decreased strongly and exponentially with autumn density. These results may explain the commonly observed univoltine life cycle and multi-annual density fluctuations in northern Chaoborus populations. They further demonstrate the relevance of winter processes and conditions for freshwater invertebrates and ecosystems. PMID:24124517

Schröder, Arne

2013-10-04

258

Antifreeze Proteins in Winter Rye Leaves Form Oligomeric Complexes1  

PubMed Central

Antifreeze proteins (AFPs) similar to three pathogenesis-related proteins, a glucanase-like protein (GLP), a chitinase-like protein (CLP), and a thaumatin-like protein (TLP), accumulate during cold acclimation in winter rye (Secale cereale) leaves, where they are thought to modify the growth of intercellular ice during freezing. The objective of this study was to characterize the rye AFPs in their native forms, and our results show that these proteins form oligomeric complexes in vivo. Nine proteins were separated by native-polyacrylamide gel electrophoresis from apoplastic extracts of cold-acclimated winter rye leaves. Seven of these proteins exhibited multiple polypeptides when denatured and separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. After isolation of the individual proteins, six were shown by immunoblotting to contain various combinations of GLP, CLP, and TLP in addition to other unidentified proteins. Antisera produced against individual cold-induced winter rye GLP, CLP, and TLP all dramatically inhibited glucanase activity in apoplastic extracts from cold-acclimated winter rye leaves, and each antiserum precipitated all three proteins. These results indicate that each of the polypeptides may be exposed on the surface of the protein complexes. By forming oligomeric complexes, AFPs may form larger surfaces to interact with ice, or they may simply increase the mass of the protein bound to ice. In either case, the complexes of AFPs may inhibit ice growth and recrystallization more effectively than the individual polypeptides.

Yu, Xiao-Ming; Griffith, Marilyn

1999-01-01

259

Winter ecology of the Arunachal macaque Macaca munzala in Pangchen Valley, western Arunachal Pradesh, northeastern India.  

PubMed

The newly described Arunachal macaque Macaca munzala occurs largely in sub-tropical to temperate environments at elevations of c. 1,800-3,000 m in Arunachal Pradesh, northeastern India. We studied its over-wintering strategy by comparing the diet, ranging, and behavior of a troop of 24 individuals during winter and spring (December 2005 to May 2006) through instantaneous scan sampling (3,002 records, 448 scans, 112 hr of observation). We also monitored the phenology of food plants. The macaques spent more time (41-66%) feeding in the winter than in spring (33-51%), whereas time spent moving and resting was greater in spring. The diet composed largely of plants, with animal matter being eaten rarely. The number of plant species in the diet increased from 18 to 25 whereas food types rose from 18 to 36 from winter to spring, respectively. Although only two species formed 75% of the winter diet, seven species comprised this proportion in spring. Availability of fruits and young leaves increased in spring; the troop moved more and utilized a larger part of its range during this time. Seasonal changes in behavior could be explained by the scarcity of food and the costs of thermoregulation in winter. Our study suggests that the Arunachal macaque inhabits a highly seasonal environment and has an over-wintering strategy that includes subsisting on a high-fiber diet by increasing the time spent feeding, and minimizing energy expenditure by reducing the time spent moving. PMID:19655365

Mendiratta, Uttara; Kumar, Ajith; Mishra, Charudutt; Sinha, Anindya

2009-11-01

260

Hibernation in an antarctic fish: on ice for winter.  

PubMed

Active metabolic suppression in anticipation of winter conditions has been demonstrated in species of mammals, birds, reptiles and amphibians, but not fish. This is because the reduction in metabolic rate in fish is directly proportional to the decrease in water temperature and they appear to be incapable of further suppressing their metabolic rate independently of temperature. However, the Antarctic fish (Notothenia coriiceps) is unusual because it undergoes winter metabolic suppression irrespective of water temperature. We assessed the seasonal ecological strategy by monitoring swimming activity, growth, feeding and heart rate (f(H)) in N. coriiceps as they free-ranged within sub-zero waters. The metabolic rate of wild fish was extrapolated from f(H )recordings, from oxygen consumption calibrations established in the laboratory prior to fish release. Throughout the summer months N. coriiceps spent a considerable proportion of its time foraging, resulting in a growth rate (G(w)) of 0.18 +/- 0.2% day(-1). In contrast, during winter much of the time was spent sedentary within a refuge and fish showed a net loss in G(w) (-0.05 +/- 0.05% day(-1)). Whilst inactive during winter, N. coriiceps displayed a very low f(H), reduced sensory and motor capabilities, and standard metabolic rate was one third lower than in summer. In a similar manner to other hibernating species, dormancy was interrupted with periodic arousals. These arousals, which lasted a few hours, occurred every 4-12 days. During arousal activity, f(H) and metabolism increased to summer levels. This endogenous suppression and activation of metabolic processes, independent of body temperature, demonstrates that N. coriiceps were effectively 'putting themselves on ice' during winter months until food resources improved. This study demonstrates that at least some fish species can enter a dormant state similar to hibernation that is not temperature driven and presumably provides seasonal energetic benefits. PMID:18320061

Campbell, Hamish A; Fraser, Keiron P P; Bishop, Charles M; Peck, Lloyd S; Egginton, Stuart

2008-03-05

261

Hibernation in an Antarctic Fish: On Ice for Winter  

PubMed Central

Active metabolic suppression in anticipation of winter conditions has been demonstrated in species of mammals, birds, reptiles and amphibians, but not fish. This is because the reduction in metabolic rate in fish is directly proportional to the decrease in water temperature and they appear to be incapable of further suppressing their metabolic rate independently of temperature. However, the Antarctic fish (Notothenia coriiceps) is unusual because it undergoes winter metabolic suppression irrespective of water temperature. We assessed the seasonal ecological strategy by monitoring swimming activity, growth, feeding and heart rate (fH) in N. coriiceps as they free-ranged within sub-zero waters. The metabolic rate of wild fish was extrapolated from fH recordings, from oxygen consumption calibrations established in the laboratory prior to fish release. Throughout the summer months N. coriiceps spent a considerable proportion of its time foraging, resulting in a growth rate (Gw) of 0.18±0.2% day?1. In contrast, during winter much of the time was spent sedentary within a refuge and fish showed a net loss in Gw (?0.05±0.05% day?1). Whilst inactive during winter, N. coriiceps displayed a very low fH, reduced sensory and motor capabilities, and standard metabolic rate was one third lower than in summer. In a similar manner to other hibernating species, dormancy was interrupted with periodic arousals. These arousals, which lasted a few hours, occurred every 4–12 days. During arousal activity, fH and metabolism increased to summer levels. This endogenous suppression and activation of metabolic processes, independent of body temperature, demonstrates that N. coriiceps were effectively ‘putting themselves on ice’ during winter months until food resources improved. This study demonstrates that at least some fish species can enter a dormant state similar to hibernation that is not temperature driven and presumably provides seasonal energetic benefits.

Campbell, Hamish A.; Fraser, Keiron P. P.; Bishop, Charles M.; Peck, Lloyd S.; Egginton, Stuart

2008-01-01

262

Comparison of camel tear proteins between summer and winter  

PubMed Central

Purpose Proteins in the tear fluid have positive effects on maintaining the integrity and stabilization of the tear film, which is affected by several environmental factors. The aim of this study is to investigate seasonal variation of protein patterns in camel tears collected during the summer and winter season. Methods Tears from both eyes of 50 clinically normal camels (Camelus dromedarius) were collected in the summer (June – July) and in the winter (December – January) respectively. Pooled tear protein samples from two seasons were separated by SDS–PAGE and two-dimensional electrophoresis (2-DE). Protein spots of differential expression in two season gels were excised and subjected to in-gel digestion and identification by matrix assisted laser desorption/ionization-time of flight/time of flight-mass spectrum (MALDI-TOF/TOF-MS) analysis. Two differentially expressed proteins, lactoferrin (LF) and vitelline membrane outer layer protein 1 homolog (VMO1 homolog), were validated by western blotting. Results Thirteen well resolved bands were detected in SDS–PAGE gels of both summer and winter camel tears. By band densitometry, significantly higher intensities of band 6, 7, 11, and lower intensity of band 13 were observed in the summer group compared to the winter group. In 2-DE profiles of camel tears, four protein spots were found expressed differentially in two seasons. Further protein identification by MALDI-TOF/TOF-MS and confirmation by western blotting indicated that there was a significant decrease in LF (p=0.002) and an increase in VMO1 homolog (p=0.042) in tears in the summer compared to the winter. Conclusions The seasonal variation of camel tear fluids has been found in the composition of proteins, including LF and VMO1 homolog. This result will expand our knowledge of physiologic characteristics of tear fluids and establish a foundation for the mechanistic studies and clinical practices on ocular surface disorders.

Chen, Ziyan; Shamsi, Farrukh A.; Li, Kaijun; Huang, Qiang; Al-Rajhi, Ali A.; Chaudhry, Imtiaz A.

2011-01-01

263

Diagnostics of Winter Precipitation Over the Western Himalayas  

NASA Astrophysics Data System (ADS)

The Indian subcontinent is surrounded by the mighty Himalayas in the north. It is characterized by heterogeneous topography and landuse variability from west to east. Apart from these, due to seasonal changes western, central and eastern Himalayas are having different precipitation patterns. In the present study winter (Dec, Jan, Feb - DJF) precipitation over the western Himalayas (WH) is analyzed. The WH receives almost one third of annual precipitation due to eastward moving cyclonic storms, Western Disturbance, during winter. Wet and dry winter precipitation years' composites show strengthening of westerly at 200 and 500 hPa and southerly at 850hPa during wet winters. Also, at 200hPa higher westerly with significant region from Saudi Arabia to Indian subcontinent and at 850hPa higher southerly with significant region from Afghanistan and adjoining Pakistan is discernible. Large scale wind field shows existence of wavelike pattern during wet years. Higher water vapor flux and outgoing longwave radiation corroborate with wet winter conditions. Further analysis based on composite years' daily pentad climatology illustrates spells of higher precipitation in wet year than that in dry year. Analysis of some individual composite peak precipitation days show formation of cyclonic flow west of 80oE at 500hPa in large scale westerly than that in the seasonal average. In addition distinct lower geopotential field difference between 500 to 925hPa is seen over Saudi Arabia to north of India. Increased convergence of water vapor flux over Arabian Sea is observed during wet precipitation years. Such changes in large scale fields suggest that during wet period flow patterns become conducive for higher precipitation over the WH. The mechanism responsible for these circulation patterns for wet (or dry) spells and years will also be discussed at the session.

Dimri, A. P.; Yasunari, T.

2011-12-01

264

Chemical depletion of Arctic ozone in winter 1999/2000  

NASA Astrophysics Data System (ADS)

During Arctic winters with a cold, stable stratospheric circulation, reactions on the surface of polar stratospheric clouds (PSCs) lead to elevated abundances of chlorine monoxide (ClO) that, in the presence of sunlight, destroy ozone. Here we show that PSCs were more widespread during the 1999/2000 Arctic winter than for any other Arctic winter in the past two decades. We have used three fundamentally different approaches to derive the degree of chemical ozone loss from ozonesonde, balloon, aircraft, and satellite instruments. We show that the ozone losses derived from these different instruments and approaches agree very well, resulting in a high level of confidence in the results. Chemical processes led to a 70% reduction of ozone for a region ˜1 km thick of the lower stratosphere, the largest degree of local loss ever reported for the Arctic. The Match analysis of ozonesonde data shows that the accumulated chemical loss of ozone inside the Arctic vortex totaled 117 ± 14 Dobson units (DU) by the end of winter. This loss, combined with dynamical redistribution of air parcels, resulted in a 88 ± 13 DU reduction in total column ozone compared to the amount that would have been present in the absence of any chemical loss. The chemical loss of ozone throughout the winter was nearly balanced by dynamical resupply of ozone to the vortex, resulting in a relatively constant value of total ozone of 340 ± 50 DU between early January and late March. This observation of nearly constant total ozone in the Arctic vortex is in contrast to the increase of total column ozone between January and March that is observed during most years.

Rex, M.; Salawitch, R. J.; Harris, N. R. P.; von der Gathen, P.; Braathen, G. O.; Schulz, A.; Deckelmann, H.; Chipperfield, M.; Sinnhuber, B.-M.; Reimer, E.; Alfier, R.; Bevilacqua, R.; Hoppel, K.; Fromm, M.; Lumpe, J.; Küllmann, H.; KleinböHl, A.; Bremer, H.; von KöNig, M.; Künzi, K.; Toohey, D.; VöMel, H.; Richard, E.; Aikin, K.; Jost, H.; Greenblatt, J. B.; Loewenstein, M.; Podolske, J. R.; Webster, C. R.; Flesch, G. J.; Scott, D. C.; Herman, R. L.; Elkins, J. W.; Ray, E. A.; Moore, F. L.; Hurst, D. F.; Romashkin, P.; Toon, G. C.; Sen, B.; Margitan, J. J.; Wennberg, P.; Neuber, R.; Allart, M.; Bojkov, B. R.; Claude, H.; Davies, J.; Davies, W.; de Backer, H.; Dier, H.; Dorokhov, V.; Fast, H.; Kondo, Y.; Kyrö, E.; Litynska, Z.; Mikkelsen, I. S.; Molyneux, M. J.; Moran, E.; Nagai, T.; Nakane, H.; Parrondo, C.; Ravegnani, F.; Skrivankova, P.; Viatte, P.; Yushkov, V.

2002-10-01

265

Selenium accumulation in sea ducks wintering at Lake Ontario.  

PubMed

Numbers of wintering sea ducks, including buffleheads (Bucephala albeola; BUFF), common goldeneyes (Bucephala clangula; COGO), and long-tailed ducks (Clangula hyemalis; LTDU), increased substantially at Lake Ontario after Dreissenid mussels (Dreissena bugensis and D. polymorpha) colonized the Great Lakes. Invertebrates, including Dreissenid mussels, are major diving duck prey items that can transfer some trace elements, such as selenium (Se) to higher trophic levels. Se can be problematic for waterfowl and it often has been detected at elevated levels in organisms using the Great Lakes. There are, however, few data on hepatic Se concentrations in sea ducks, particularly during the winter at Lake Ontario. In this study, we evaluated interspecific differences and temporal trends in hepatic Se concentrations among BUFF (n = 77), COGO (n = 77), and LTDU (n = 79) wintering at Lake Ontario. All three species accumulated Se throughout winter, but COGO did so at a higher rate than did BUFF and LTDU. Overall, Se concentrations were higher in LTDU [mean = 22.7; 95% CI = 20.8-24.8 microg/g dry weight (dw)] than in BUFF ([mean = 12.3; 95% CI = 11.6-13.1 microg/g dw) and COGO ([mean = 12.0; 95% CI = 10.7-3.5 microg/g dw) throughout the winter. Se concentrations were deemed elevated (>33 microg/g dw) in 0%, 5%, and 19% of BUFF, COGO, and LTDU, respectively. Presently there are no data on Se toxicity end points for these species, so it is unclear how acquiring concentrations of these magnitudes affect their short- and long-term health or reproduction. PMID:19653029

Schummer, Michael L; Badzinski, Shannon S; Petrie, Scott A; Chen, Yu-Wei; Belzile, Nelson

2009-08-04

266

An analysis of US propane markets, winter 1996-1997  

SciTech Connect

In late summer 1996, in response to relatively low inventory levels and tight world oil markets, prices for crude oil, natural gas, and products derived from both began to increase rapidly ahead of the winter heating season. Various government and private sector forecasts indicated the potential for supply shortfalls and sharp price increases, especially in the event of unusually severe winter weather. Following a rapid runup in gasoline prices in the spring of 1996, public concerns were mounting about a possibly similar situation in heating fuels, with potentially more serious consequences. In response to these concerns, the Energy Information Administration (EIA) participated in numerous briefings and meetings with Executive Branch officials, Congressional committee members and staff, State Energy Offices, and consumers. EIA instituted a coordinated series of actions to closely monitor the situation and inform the public. This study constitutes one of those actions: an examination of propane supply, demand, and price developments and trends.

NONE

1997-06-01

267

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.

Chawade, Aakash; Linden, Pernilla; Brautigam, Marcus; Jonsson, Rickard; Jonsson, Anders; Moritz, Thomas; Olsson, Olof

2012-01-01

268

Observed and predicted Great Lakes winter circulations  

SciTech Connect

Observed mean winter currents in Lakes Ontario and Huron are compared to predictions from a homogeneous, vertically integrated, steady-state model. If specific wind directions are selected to drive this model, the observed and predicted current patterns agree. The specific wind directions were chosen to maximize each lake's wind response. The agreement suggests that there is a mean wind-driven winter circulation in the Great Lakes, and that its pattern depends upon these specific wind directions. Based on these factors, winter circulations for Lakes Erie, Huron and Superior are predicted.

Pickett, R.L.

1980-07-01

269

Impacts of extreme winter warming events on plant physiology in a sub-Arctic heath community.  

PubMed

Insulation provided by snow cover and tolerance of freezing by physiological acclimation allows Arctic plants to survive cold winter temperatures. However, both the protection mechanisms may be lost with winter climate change, especially during extreme winter warming events where loss of snow cover from snow melt results in exposure of plants to warm temperatures and then returning extreme cold in the absence of insulating snow. These events cause considerable damage to Arctic plants, but physiological responses behind such damage remain unknown. Here, we report simulations of extreme winter warming events using infrared heating lamps and soil warming cables in a sub-Arctic heathland. During these events, we measured maximum quantum yield of photosystem II (PSII), photosynthesis, respiration, bud swelling and associated bud carbohydrate changes and lipid peroxidation to identify physiological responses during and after the winter warming events in three dwarf shrub species: Empetrum hermaphroditum, Vaccinium vitis-idaea and Vaccinium myrtillus. Winter warming increased maximum quantum yield of PSII, and photosynthesis was initiated for E. hermaphroditum and V. vitis-idaea. Bud swelling, bud carbohydrate decreases and lipid peroxidation were largest for E. hermaphroditum, whereas V. myrtillus and V. vitis-idaea showed no or less strong responses. Increased physiological activity and bud swelling suggest that sub-Arctic plants can initiate spring-like development in response to a short winter warming event. Lipid peroxidation suggests that plants experience increased winter stress. The observed differences between species in physiological responses are broadly consistent with interspecific differences in damage seen in previous studies, with E. hermaphroditum and V. myrtillus tending to be most sensitive. This suggests that initiation of spring-like development may be a major driver in the damage caused by winter warming events that are predicted to become more frequent in some regions of the Arctic and that may ultimately drive plant community shifts. PMID:20497369

Bokhorst, Stef; Bjerke, Jarle W; Davey, Matthew P; Taulavuori, Kari; Taulavuori, Erja; Laine, Kari; Callaghan, Terry V; Phoenix, Gareth K

2010-10-01

270

Winter wheat quantity or quality? Assessing food security in Uzbekistan  

Microsoft Academic Search

Winter wheat is the most important cereal in Uzbekistan. Although the processing industry recognizes the low quality of local\\u000a wheat, the present land use policy prioritizes production quantity, and wheat of better quality is imported to improve local\\u000a flour. Yet, with increasing world market prices, Uzbekistan has to decide whether to continue allocating considerable resources\\u000a for imports or to start

Kirsten Maren Kienzler; Inna Rudenko; Jumanazar Ruzimov; Nazar Ibragimov; John P. A Lamers

2011-01-01

271

The urban heat island in winter at Barrow, Alaska  

NASA Astrophysics Data System (ADS)

The village of Barrow, Alaska, is the northernmost settlement in the USA and the largest native community in the Arctic. The population has grown from about 300 residents in 1900 to more than 4600 in 2000. In recent decades, a general increase of mean annual and mean winter air temperature has been recorded near the centre of the village, and a concurrent trend of progressively earlier snowmelt in the village has been documented. Satellite observations and data from a nearby climate observatory indicate a corresponding but much weaker snowmelt trend in the surrounding regions of relatively undisturbed tundra. Because the region is underlain by ice-rich permafrost, there is concern that early snowmelt will increase the thickness of the thawed layer in summer and threaten the structural stability of roads, buildings, and pipelines. Here, we demonstrate the existence of a strong urban heat island (UHI) during winter. Data loggers (54) were installed in the 150 km2 study area to monitor hourly air and soil temperature, and daily spatial averages were calculated using the six or seven warmest and coldest sites. During winter (December 2001-March 2002), the urban area averaged 2.2 °C warmer than the hinterland. The strength of the UHI increased as the wind velocity decreased, reaching an average value of 3.2 °C under calm (<2 m s-1) conditions and maximum single-day magnitude of 6 °C. UHI magnitude generally increased with decreasing air temperature in winter, reflecting the input of anthropogenic heat to maintain interior building temperatures. On a daily basis, the UHI reached its peak intensity in the late evening and early morning. There was a strong positive relation between monthly UHI magnitude and natural gas production/use. Integrated over the period September-May, there was a 9% reduction in accumulated freezing degree days in the urban area. The evidence suggests that urbanization has contributed to early snowmelt in the village.

Hinkel, Kenneth M.; Nelson, Frederick E.; Klene, Anna E.; Bell, Julianne H.

2003-12-01

272

Winter Polyculture of Channel Catfish and Rainbow Trout in Cages  

Microsoft Academic Search

Under winter conditions in Oklahoma (1.0–20.0°C; average, 7.0°C), polyculture of caged channel catfish (Ictalurus punctatus) and rainbow trout (Salmo gairdneri) resulted in a significantly higher channel catfish weight gain (about 6.5%; P < 0.05) than that observed in channel catfish monoculture (–3.8% gain). Channel catfish also experienced increased growth as a function of proximity to rainbow trout in neighboring cages.

Marley D. Beem; Glen E. Gebhart; O. Eugene Maughan

1988-01-01

273

In situ measurements of midlatitude ClO in winter  

Microsoft Academic Search

In situ measurements of ClO in the winter lower stratosphere are presented for six flights of the NASA ER-2 aircraft from 38°N to 61°N. Enhanced abundances, increasing in severity with data, were observed below 20 km, where HCl and ClONOâ dominate the inorganic chlorine budget. The greatest mixing ratios, over 150 pptv, were encountered on February 20 and 21, 1989,

D. W. Toohey; J. G. Anderson; W. H. Brune; K. R. Chan

1991-01-01

274

Winter Survival of Transgenic Alfalfa Overexpressing Superoxide Dismutase  

Microsoft Academic Search

To test the hypothesis that enhanced tolerance of oxidative stress would improve winter survival, two clones of alfalfa (Medicago sativa) were transformed with a Mn-superoxide dismutase (Mn- SOD) targeted to the mitochondria or to the chloroplast. Although Mn-SOD activity increased in most primary transgenic plants, both cytosolic and chloroplastic forms of Cu\\/Zn-SOD had lower activity in the chloroplast SOD transgenic

Bryan D. McKersie; Stephen R. Bowley; Kim S. Jones

1999-01-01

275

Selenium Accumulation in Sea Ducks Wintering at Lake Ontario  

Microsoft Academic Search

Numbers of wintering sea ducks, including buffleheads (Bucephala albeola; BUFF), common goldeneyes (Bucephala clangula; COGO), and long-tailed ducks (Clangula hyemalis; LTDU), increased substantially at Lake Ontario after Dreissenid mussels (Dreissena bugensis and D. polymorpha) colonized the Great Lakes. Invertebrates, including Dreissenid mussels, are major diving duck prey items that can transfer\\u000a some trace elements, such as selenium (Se) to higher

Michael L. Schummer; Shannon S. Badzinski; Scott A. Petrie; Yu-Wei Chen; Nelson Belzile

2010-01-01

276

Winter warming from large volcanic eruptions  

SciTech Connect

An examination of the Northern Hemisphere winter surface temperature patterns after the 12 largest volcanic eruptions from 1883-1992 shows warming over Eurasia and North America and cooling over the Middle East which are significant at the 95% level. This pattern is found in the first winter after tropical eruptions, in the first or second winter after midlatitude eruptions, and in the second winter after high latitude eruptions. The effects are independent of the hemisphere of the volcanoes. An enhanced zonal wind driven by heating of the tropical stratosphere by the volcanic aerosols is responsible for the regions of warming, while the cooling is caused by blocking of incoming sunlight. 21 refs., 2 figs., 1 tab.

Robock, A.; Jianping Mao (Univ. of Maryland, College Park (United States))

1992-12-24

277

Nuclear Winter: The Implications for Civil Defense.  

National Technical Information Service (NTIS)

''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 ...

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

1987-01-01

278

Implications of the 'Nuclear Winter' Thesis.  

National Technical Information Service (NTIS)

This report assesses the potential policy implications of new findings concerning the long-term atmospheric, climatic and biological effects of nuclear war, commonly referred to as nuclear winter. A summary of the prominent study of these effects, The Glo...

C. B. Feldbaum R. J. Bee B. N. Garrett B. S. Glasner

1985-01-01

279

Three Approaches to Winter Traction Testing.  

National Technical Information Service (NTIS)

Traction on winter surfaces was measured using three test vehicles, each designed to measure traction for a different purpose: vehicle mobility research (CRREL Instrumented Vehicle), commercial tire testing (Uniroyal-Goodrich traction tester), and airport...

S. A. Shoop

1993-01-01

280

Mesoscale Precipitation Systems in Winter Storms.  

National Technical Information Service (NTIS)

Heavy frozen precipitation produced by complex mesoscale patterns embedded within winter extratropical cyclones (ETCs) adversely affect many areas of the United States each year. The initiation, organization, and movement of these mesoscale precipitation ...

M. A. Kaster

1993-01-01

281

Earth-Sun Geometry: Winter Solstice Animation  

NSDL National Science Digital Library

The representation depicts the position of the Earth relative to the Sun during the southern hemisphere's winter solstice and includes line of latitude and the angle of the Sun's rays at the Tropic of Capricorn.

Pidwirny, Michael; Okanagan, Scott J.

282

Winter Ice Jams on the Gunnison River.  

National Technical Information Service (NTIS)

The formation, transport, and accumulation of ice is an annual occurrence on many rivers. This report summarizes winter observations conducted on a mountain river in the State of Colorado. The Gunnison River observations were conducted along the 14-km rea...

P. H. Burgi

1979-01-01

283

Mojave sandy desert habitat in Winter (February)  

NSDL National Science Digital Library

By winter in non-drought years, the Mojave has received several inches of rain and healthy vegetation will begin to break ground by February. However, during drought years, vegetation will not experience its rapid growth season until spring.

Katie Hale (California State University, Fullerton;Student, Biological Sciences)

2007-01-06

284

How to Find Insects Weathering the Winter.  

ERIC Educational Resources Information Center

|Discusses how and where to find insects and other invertebrates in winter, as well as how to collect samples in order to watch those animals reappear in spring. Includes crickets, honey bees, mosquitoes, house flies, and butterflies and moths. (MA)|

Brody, Jane

1979-01-01

285

Spike Differentiation in Winter Wheat (Triticum aestivum L.) Mulched with Plastic Films During OverWintering Period  

Microsoft Academic Search

To determine the effects of plastic film mulching on spike differentiation in winter wheat, two varieties (3291 and XZ25) and seven mulching treatments consisting of three mulching dates and two film removal dates and a non-mulched control (CK) were used. In the film-mulched treatments, the increase in weekly minimum soil surface temperature due to mulching was 4.1°C (P < 0.01)

Jianmin Li; Hongxia Liu; Liusheng Duan; A. Egrinya Eneji; Zhaohu Li

2008-01-01

286

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

287

Winter Survival of Individual Honey Bees and Honey Bee Colonies Depends on Level of Varroa destructor Infestation  

PubMed Central

Background Recent elevated winter loss of honey bee colonies is a major concern. The presence of the mite Varroa destructor in colonies places an important pressure on bee health. V. destructor shortens the lifespan of individual bees, while long lifespan during winter is a primary requirement to survive until the next spring. We investigated in two subsequent years the effects of different levels of V. destructor infestation during the transition from short-lived summer bees to long-lived winter bees on the lifespan of individual bees and the survival of bee colonies during winter. Colonies treated earlier in the season to reduce V. destructor infestation during the development of winter bees were expected to have longer bee lifespan and higher colony survival after winter. Methodology/Principal Findings Mite infestation was reduced using acaricide treatments during different months (July, August, September, or not treated). We found that the number of capped brood cells decreased drastically between August and November, while at the same time, the lifespan of the bees (marked cohorts) increased indicating the transition to winter bees. Low V. destructor infestation levels before and during the transition to winter bees resulted in an increase in lifespan of bees and higher colony survival compared to colonies that were not treated and that had higher infestation levels. A variety of stress-related factors could have contributed to the variation in longevity and winter survival that we found between years. Conclusions/Significance This study contributes to theory about the multiple causes for the recent elevated colony losses in honey bees. Our study shows the correlation between long lifespan of winter bees and colony loss in spring. Moreover, we show that colonies treated earlier in the season had reduced V. destructor infestation during the development of winter bees resulting in longer bee lifespan and higher colony survival after winter.

van Dooremalen, Coby; Gerritsen, Lonne; Cornelissen, Bram; van der Steen, Jozef J. M.; van Langevelde, Frank; Blacquiere, Tjeerd

2012-01-01

288

ENSO and winter storms in California  

USGS Publications Warehouse

The frequency and intensity of North Pacific winter storms that penetrate the California coast drives the winds, sea level, precipitation and streamflow that are crucial influences on coastal processes. There is considerable variability of these storm characteristics, in large part owing to the El Nino/Southern Oscillation (ENSO} phenomenon. There is a great contrast of the storm characteristics during the El Nino phase vs. the La Nina phase, with the largest scale, southerly extensive winter storms generated during El Nino.

Cayan, D. R.; Bromirski, P.

2003-01-01

289

Solvent winterization of sunflower seed oil  

Microsoft Academic Search

Samples of oil from whole and dehulled sunflower seed were solvent winterized. The solvent mixture, 85% acetone, 15% hexane\\u000a (v\\/v), was used at solvent-in-oil concentrations of 20, 40, and 70% by wt and the samples winterized at 0, ?5, ?10, and ?15\\u000a .01 C for 4 hr. Generally, sunflower oils from whole seed remained free from cloud formation longer on

W. Herbert Morrison; James A. Robertson

1975-01-01

290

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.

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

2013-01-01

291

Some policy implications of nuclear winter  

SciTech Connect

The theory of nuclear winter has had as checkered a history as any new idea since Darwin published The Origin of Species. There have been questions of its scientific validity, reviews both laudatory and damning, pleas for arms reductions, hosannahs for a newfound hope that nuclear war has at least been rendered completely unthinkable, and frustration that two generations of human toil in weapons laboratories and think tanks have been rendered by a natural doomsday machine. Some have even suggested that nuclear winter might be used as an offensive weapon. Disturbingly, a substantial number of commentators have concluded that nuclear winter carries no immediate implications for policy, because to their way of thinking, nuclear winter is a (a) just one more of the many undesirable effects of nuclear war; (b) the ulimate deterrent to nuclear use, and therefore should be welcomed rather than compensated for; or (c) an unproven theory, meaning that consideration of policy questions is premature. Those who overlook the policy questions are following a dangerous path. The nuclear winter theory contains serious short- and long-term implications for United States foreign and strategic policy. Although the theory may never be confirmed or refuted, discussion of these policy questions should begin now because many of the potential effects of nuclear winter - particularly in foreign policy - will come about regardless of whether or not the phenomenon can actually exist.

Gertler, J.J.

1985-01-01

292

A metagenomic assessment of winter and summer bacterioplankton from Antarctica Peninsula coastal surface waters.  

PubMed

Antarctic surface oceans are well-studied during summer when irradiance levels are high, sea ice is melting and primary productivity is at a maximum. Coincident with this timing, the bacterioplankton respond with significant increases in secondary productivity. Little is known about bacterioplankton in winter when darkness and sea-ice cover inhibit photoautotrophic primary production. We report here an environmental genomic and small subunit ribosomal RNA (SSU rRNA) analysis of winter and summer Antarctic Peninsula coastal seawater bacterioplankton. Intense inter-seasonal differences were reflected through shifts in community composition and functional capacities encoded in winter and summer environmental genomes with significantly higher phylogenetic and functional diversity in winter. In general, inferred metabolisms of summer bacterioplankton were characterized by chemoheterotrophy, photoheterotrophy and aerobic anoxygenic photosynthesis while the winter community included the capacity for bacterial and archaeal chemolithoautotrophy. Chemolithoautotrophic pathways were dominant in winter and were similar to those recently reported in global 'dark ocean' mesopelagic waters. If chemolithoautotrophy is widespread in the Southern Ocean in winter, this process may be a previously unaccounted carbon sink and may help account for the unexplained anomalies in surface inorganic nitrogen content. PMID:22534611

Grzymski, Joseph J; Riesenfeld, Christian S; Williams, Timothy J; Dussaq, Alex M; Ducklow, Hugh; Erickson, Matthew; Cavicchioli, Ricardo; Murray, Alison E

2012-04-26

293

A metagenomic assessment of winter and summer bacterioplankton from Antarctica Peninsula coastal surface waters  

PubMed Central

Antarctic surface oceans are well-studied during summer when irradiance levels are high, sea ice is melting and primary productivity is at a maximum. Coincident with this timing, the bacterioplankton respond with significant increases in secondary productivity. Little is known about bacterioplankton in winter when darkness and sea-ice cover inhibit photoautotrophic primary production. We report here an environmental genomic and small subunit ribosomal RNA (SSU rRNA) analysis of winter and summer Antarctic Peninsula coastal seawater bacterioplankton. Intense inter-seasonal differences were reflected through shifts in community composition and functional capacities encoded in winter and summer environmental genomes with significantly higher phylogenetic and functional diversity in winter. In general, inferred metabolisms of summer bacterioplankton were characterized by chemoheterotrophy, photoheterotrophy and aerobic anoxygenic photosynthesis while the winter community included the capacity for bacterial and archaeal chemolithoautotrophy. Chemolithoautotrophic pathways were dominant in winter and were similar to those recently reported in global ‘dark ocean' mesopelagic waters. If chemolithoautotrophy is widespread in the Southern Ocean in winter, this process may be a previously unaccounted carbon sink and may help account for the unexplained anomalies in surface inorganic nitrogen content.

Grzymski, Joseph J; Riesenfeld, Christian S; Williams, Timothy J; Dussaq, Alex M; Ducklow, Hugh; Erickson, Matthew; Cavicchioli, Ricardo; Murray, Alison E

2012-01-01

294

El Niño-Southern Oscillation Impacts on Winter Vegetable Production in Florida*.  

NASA Astrophysics Data System (ADS)

Florida's mild winters allow the state to play a vital role in supplying fresh vegetables for U.S. consumers. Producers also benefit from premium prices when low temperatures prevent production in most of the country. This study characterizes the influence of the El Niño-Southern Oscillation (ENSO) on the Florida vegetable industry using statistical analysis of the response of historical crop (yield, prices, production, and value) and weather variables (freeze hazard, temperatures, rainfall, and solar radiation) to ENSO phase and its interaction with location and time of year. Annual mean yields showed little evidence of response to ENSO phase and its interaction with location. ENSO phase and season interacted to influence quarterly yields, prices, production, and value. Yields (tomato, bell pepper, sweet corn, and snap bean) were lower and prices (bell pepper and snap bean) were higher in El Niño than in neutral or La Niña winters. Production and value of tomatoes were higher in La Niña winters. The yield response can be explained by increased rainfall, reduced daily maximum temperatures, and reduced solar radiation in El Niño winters. Yield and production of winter vegetables appeared to be less responsive to ENSO phase after 1980; for tomato and bell pepper, this may be due to improvements in production technology that mitigate problems associated with excess rainfall. Winter yield and price responses to El Niño events have important implications for both producers and consumers of winter vegetables, and suggest opportunities for further research.

Hansen, James W.; Jones, James W.; Kiker, Clyde F.; Hodges, Alan W.

1999-01-01

295

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

PubMed

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. PMID:23423627

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

2013-02-20

296

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

2013-02-01

297

In situ measurements of midlatitude ClO in winter  

SciTech Connect

In situ measurements of ClO in the winter lower stratosphere are presented for six flights of the NASA ER-2 aircraft from 38{degree}N to 61{degree}N. Enhanced abundances, increasing in severity with data, were observed below 20 km, where HCl and ClONO{sub 2} dominate the inorganic chlorine budget. The greatest mixing ratios, over 150 pptv, were encountered on February 20 and 21, 1989, as the vortex experienced a major warming. Although the timing of these ClO enhancements and the evidence that vortex air can reach midlatitudes, the enhancements observed early in the winter could have been caused by unknown chemistry occurring outside the vortex. In either case, photochemical loss of ozone due to catalytic reactions involving ClO at these mixing ratios may be responsible in part for the ozone decreases observed at high latitudes in the northern hemisphere.

Toohey, D.W.; Anderson, J.G. (Harvard Univ., Cambridge, MA (USA)); Brune, W.H. (Pennsylvania State Univ., University Park (USA)); Chan, K.R. (NASA Ames Research Center, Moffett Field, CA (USA))

1991-01-01

298

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

299

Dissolved oxygen in the Tualatin River, Oregon, during winter flow conditions, 1991 and 1992  

USGS Publications Warehouse

Throughout the winter period, November through April, wastewater treatment plants in the Tualatin River Basin discharge from 10,000 to 15,000 pounds per day of biochemical oxygen demand to the river. These loads often increase substantially during storms when streamflow is high. During the early winter season, when streamflow is frequently less than the average winter flow, the treatment plants discharge about 2,000 pounds per day of ammonia. This study focused on the capacity of the Tualatin River to assimilat oxygen-demanding loads under winter streamflow conditions during the 1992 water year, with an emphasis on peak-flow conditions in the river, and winter-base-flow conditions during November 1992. Concentrations of dissolved oxygen throughout the main stem of the river during the winter remained generally high relative to the State standard for Oregon of 6 milligrams per liter. The most important factors controlling oxygen consumption during winter-low-flow conditions were carbonaceous biochemical oxygen demand and input of oxygen-depleted waters from tributaries. During peak-flow conditions, reduced travel time and increased dilution associated with the increased streamflow minimized the effect of increased oxygen-demanding loads. During the base-flow period in November 1992, concentrations of dissolved oxygen were consistently below 6 milligrams per liter. A hydrodynamic water-quality model was used to identify the processes depleting dissolved oxygen, including sediment oxygen demand, nitrification, and carbonaceous biochemical oxygen demand. Sediment oxygen demand was the most significant factor; nitrification was also important. Hypothetical scenarios were posed to evaluate the effect of different wastewater treatment plant loads during winter-base-flow conditions. Streamflow and temperature were significant factors governing concentrations of dissolved oxygen in the main-stem river.

Kelly, V. J.

1996-01-01

300

A Rocky Mountain Storm. Part I: The Blizzard—Kinematic Evolution and the Potential for High-Resolution Numerical Forecasting of Snowfall  

Microsoft Academic Search

Over the 3-day period of 24-26 October 1997, a powerful winter storm was the cause of two exceptional weather phenomena: 1) blizzard conditions from Wyoming to southern New Mexico along the Front Range of the Rocky Mountains and 2) hurricane-force winds at the surface near Steamboat Springs, Colorado, with the destruction of about 5300 ha of old-growth forest. This rare

Gregory S. Poulos; Douglas A. Wesley; John S. Snook; Michael P. Meyers

2002-01-01

301

An adaptable urban house designed for the southern Brazilian climate - emphasis on summer and winter thermal comfort  

Microsoft Academic Search

SUMMARY The climate in southern Brazil is characterised by mild winters and hot-humid summers which requires the design to be adaptable to the often conflicting summer and winter requirements. In the residential sector, air conditioning consumption is still low, but it has been growing significantly along with an increase in people's purchasing power which emphasizes the importance of encouraging a

Marianne Costella

302

Soil aggregates and their associated carbon and nitrogen content in winter annual pastures using different tillage management options  

Technology Transfer Automated Retrieval System (TEKTRAN)

Traditionally, winter annual pastures are established on grazing areas that are steeply sloping and not regarded as suitable for row-crop production. Using conventional (CT) tillage methods to prepare these fragile lands for winter annual pastures leads to increased erosion and rapid soil degradatio...

303

Impact of elevated temperature on the growth, survival, and trophic dynamics of winter flounder larvae: a mesocosm study  

Microsoft Academic Search

Winter flounder (Pseudopleuronectes americanus ) is a dominant commercial fish in Narragansett Bay, Rhode Island, and yet factors controlling its recruitment remain unclear. An experiment was conducted with six 13-m 3 land- based mesocosms (5 m deep) from February to April 1997 to address the impact of increased temperature (+3°C) on growth, survival, and trophic dynamics of winter flounder larvae.

Aimee A. Keller; Grace Klein-MacPhee

2000-01-01

304

Cadmium in Soil and Winter Wheat Grain in Southern Sweden: I. Factors Influencing Cd Levels in Soils and Grain  

Microsoft Academic Search

The guideline level for Cd contents in cereals of 100 ?g kg proposed by the Codex Committee on Cereals, Pulses and Legumes has increased concern regarding Cd levels in Swedish winter wheat. In this study, Cd levels in soil and grain and factors influencing these variables were investigated in Skåne, the southernmost province in Sweden. In 1992, soils and winter

Jan. E. Eriksson; Mats Söderström

1996-01-01

305

Multistate proteomics analysis reveals novel strategies used by a hibernator to precondition the heart and conserve ATP for winter heterothermy  

PubMed Central

The hibernator's heart functions continuously and avoids damage across the wide temperature range of winter heterothermy. To define the molecular basis of this phenotype, we quantified proteomic changes in the 13-lined ground squirrel heart among eight distinct physiological states encompassing the hibernator's year. Unsupervised clustering revealed a prominent seasonal separation between the summer homeotherms and winter heterotherms, whereas within-season state separation was limited. Further, animals torpid in the fall were intermediate to summer and winter, consistent with the transitional nature of this phase. A seasonal analysis revealed that the relative abundances of protein spots were mainly winter-increased. The winter-elevated proteins were involved in fatty acid catabolism and protein folding, whereas the winter-depleted proteins included those that degrade branched-chain amino acids. To identify further state-dependent changes, protein spots were re-evaluated with respect to specific physiological state, confirming the predominance of seasonal differences. Additionally, chaperone and heat shock proteins increased in winter, including HSPA4, HSPB6, and HSP90AB1, which have known roles in protecting against ischemia-reperfusion injury and apoptosis. The most significant and greatest fold change observed was a disappearance of phospho-cofilin 2 at low body temperature, likely a strategy to preserve ATP. The robust summer-to-winter seasonal proteomic shift implies that a winter-protected state is orchestrated before prolonged torpor ensues. Additionally, the general preservation of the proteome during winter hibernation and an increase of stress response proteins, together with dephosphorylation of cofilin 2, highlight the importance of ATP-conserving mechanisms for winter cardioprotection.

Grabek, Katharine R.; Karimpour-Fard, Anis; Epperson, L. Elaine; Hindle, Allyson; Hunter, Lawrence E.

2011-01-01

306

Multistate proteomics analysis reveals novel strategies used by a hibernator to precondition the heart and conserve ATP for winter heterothermy.  

PubMed

The hibernator's heart functions continuously and avoids damage across the wide temperature range of winter heterothermy. To define the molecular basis of this phenotype, we quantified proteomic changes in the 13-lined ground squirrel heart among eight distinct physiological states encompassing the hibernator's year. Unsupervised clustering revealed a prominent seasonal separation between the summer homeotherms and winter heterotherms, whereas within-season state separation was limited. Further, animals torpid in the fall were intermediate to summer and winter, consistent with the transitional nature of this phase. A seasonal analysis revealed that the relative abundances of protein spots were mainly winter-increased. The winter-elevated proteins were involved in fatty acid catabolism and protein folding, whereas the winter-depleted proteins included those that degrade branched-chain amino acids. To identify further state-dependent changes, protein spots were re-evaluated with respect to specific physiological state, confirming the predominance of seasonal differences. Additionally, chaperone and heat shock proteins increased in winter, including HSPA4, HSPB6, and HSP90AB1, which have known roles in protecting against ischemia-reperfusion injury and apoptosis. The most significant and greatest fold change observed was a disappearance of phospho-cofilin 2 at low body temperature, likely a strategy to preserve ATP. The robust summer-to-winter seasonal proteomic shift implies that a winter-protected state is orchestrated before prolonged torpor ensues. Additionally, the general preservation of the proteome during winter hibernation and an increase of stress response proteins, together with dephosphorylation of cofilin 2, highlight the importance of ATP-conserving mechanisms for winter cardioprotection. PMID:21914784

Grabek, Katharine R; Karimpour-Fard, Anis; Epperson, L Elaine; Hindle, Allyson; Hunter, Lawrence E; Martin, Sandra L

2011-09-13

307

Summer Hot Snaps and Winter Conditions: Modelling White Syndrome Outbreaks on Great Barrier Reef Corals  

PubMed Central

Coral reefs are under increasing pressure in a changing climate, one such threat being more frequent and destructive outbreaks of coral diseases. Thermal stress from rising temperatures has been implicated as a causal factor in disease outbreaks observed on the Great Barrier Reef, Australia, and elsewhere in the world. Here, we examine seasonal effects of satellite-derived temperature on the abundance of coral diseases known as white syndromes on the Great Barrier Reef, considering both warm stress during summer and deviations from mean temperatures during the preceding winter. We found a high correlation (r2?=?0.953) between summer warm thermal anomalies (Hot Snap) and disease abundance during outbreak events. Inclusion of thermal conditions during the preceding winter revealed that a significant reduction in disease outbreaks occurred following especially cold winters (Cold Snap), potentially related to a reduction in pathogen loading. Furthermore, mild winters (i.e., neither excessively cool nor warm) frequently preceded disease outbreaks. In contrast, disease outbreaks did not typically occur following warm winters, potentially because of increased disease resistance of the coral host. Understanding the balance between the effects of warm and cold winters on disease outbreak will be important in a warming climate. Combining the influence of winter and summer thermal effects resulted in an algorithm that yields both a Seasonal Outlook of disease risk at the conclusion of winter and near real-time monitoring of Outbreak Risk during summer. This satellite-derived system can provide coral reef managers with an assessment of risk three-to-six months in advance of the summer season that can then be refined using near-real-time summer observations. This system can enhance the capacity of managers to prepare for and respond to possible disease outbreaks and focus research efforts to increase understanding of environmental impacts on coral disease in this era of rapidly changing climate.

Heron, Scott F.; Willis, Bette L.; Skirving, William J.; Eakin, C. Mark; Page, Cathie A.; Miller, Ian R.

2010-01-01

308

Small rodent winter survival: snow conditions limit access to food resources.  

PubMed

1. In Fennoscandia during winter small rodents spend most of their time in the subnivean space, between the snow cover and the ground. The subnivean space is probably not a uniform habitat, but broken into accessible and inaccessible patches by ice covering the vegetation. This might reduce access to otherwise available food resources. 2. To test whether ice formations reduce access to food and thus limit winter survival of small rodents, we conducted an experiment where we increased subnivean space by adding corrugated aluminium sheets on the ground before onset of winter. The sheets prevented ice formation, thus mimicking natural occurring subnivean space, and providing more room for animals living in the subnivean space to forage. 3. During the experiment 142 Microtus oeconomus were passive induced transponder (PIT)-tagged, and a system consisting of fixed tube-shaped antennas and PIT-tag readers were used to provide data to analyse winter survival and individual subnivean space use. The extent of winter grazing was measured after snow melt by examining percentage area grazed. 4. The treatment resulted in increased survival which corresponded well with significantly higher space use and more grazing under the sheets. 5. Females showed a positive correlation between probability of survival and body mass while no such effect was observed in males. 6. The results suggest that the snow cover reduces survival in winter by physically enclosing the vegetation in ice and thus reducing access to otherwise available food resources. The amount of ice and its configuration might vary between years due to changing weather patterns. Our results offer a mechanistic explanation for variations in winter survival and suggest incorporating climate variables in future small rodent models. 7. Directional and long-term changes in climate might result in increased ice formation in the subnivean system. Such deterioration may lead to reduced winter survival and act by stabilizing population dynamics and dampening vole cyclicity. PMID:16903053

Korslund, Lars; Steen, Harald

2006-01-01

309

Winter climate change effects on soil C and N cycles in urban grasslands.  

PubMed

Despite growing recognition of the role that cities have in global biogeochemical cycles, urban systems are among the least understood of all ecosystems. Urban grasslands are expanding rapidly along with urbanization, which is expected to increase at unprecedented rates in upcoming decades. The large and increasing area of urban grasslands and their impact on water and air quality justify the need for a better understanding of their biogeochemical cycles. There is also great uncertainty about the effect that climate change, especially changes in winter snow cover, will have on nutrient cycles in urban grasslands. We aimed to evaluate how reduced snow accumulation directly affects winter soil frost dynamics, and indirectly greenhouse gas fluxes and the processing of carbon (C) and nitrogen (N) during the subsequent growing season in northern urban grasslands. Both artificial and natural snow reduction increased winter soil frost, affecting winter microbial C and N processing, accelerating C and N cycles and increasing soil : atmosphere greenhouse gas exchange during the subsequent growing season. With lower snow accumulations that are predicted with climate change, we found decreases in N retention in these ecosystems, and increases in N2 O and CO2 flux to the atmosphere, significantly increasing the global warming potential of urban grasslands. Our results suggest that the environmental impacts of these rapidly expanding ecosystems are likely to increase as climate change brings milder winters and more extensive soil frost. PMID:23630015

Durán, Jorge; Rodríguez, Alexandra; Morse, Jennifer L; Groffman, Peter M

2013-05-29

310

No difference found between winter- and non-winter-born schizophrenic cases  

Microsoft Academic Search

The distinction between winter-born (WBS) and non-winter born (NWBS) schizophrenic cases has been proposed as a strategy to identify distinct etiologic subtypes within schizophrenia, the WBS subgroup being a predominantly environmental subtype. The goal of this paper is to empirically test the validity of this strategy by comparing WBS and NWBS groups on a broad array of clinical and biological

Marc-André Roy; Michael Flaum; Nancy C. Andreasen

1995-01-01

311

Record low total ozone during northern winters of 1992 and 1993  

SciTech Connect

The authors look at recorded ozone data over the northern hemisphere during the winters of 1992 and 1993. They use data from the World Meteorological Organization data base. During both of these winter, there have been marked decreases in the column ozone levels over North America, Europe, and Siberia, in the latitude belt from 45[degrees]N to 65[degrees]N. During these winters there have been ten times as many days with ozone levels deviated more than 2[sigma] below the 35 year average. They seek explanations for these observations by looking at meterological information. Evidences indicate that there was transport of ozone deficient air masses during these winters. In addition cold air masses with excess ClO show evidence of having transported into the more southern latitudes. The authors conclude there is evidence for both displacement of large air masses, and increased chemical destruction potential, to have contributed to these observed decreases.

Bojkov, R.D. (World Meteorological Organization, Geneva (Switzerland))

1993-07-09

312

Ethylene Induces Antifreeze Activity in Winter Rye Leaves1  

PubMed Central

Antifreeze activity is induced by cold temperatures in winter rye (Secale cereale) leaves. The activity arises from six antifreeze proteins that accumulate in the apoplast of winter rye leaves during cold acclimation. The individual antifreeze proteins are similar to pathogenesis-related proteins, including glucanases, chitinases, and thaumatin-like proteins. The objective of this study was to study the regulation of antifreeze activity in response to ethylene and salicyclic acid, which are known regulators of pathogenesis-related proteins induced by pathogens. Nonacclimated plants treated with salicylic acid accumulated apoplastic proteins with no antifreeze activity. In contrast, when nonacclimated plants were exposed to ethylene, both antifreeze activity and the concentration of apoplastic protein increased in rye leaves. Immunoblotting revealed that six of the seven accumulated apoplastic proteins consisted of two glucanases, two chitinases, and two thaumatin-like proteins. The ethylene-releasing agent ethephon and the ethylene precursor 1-aminocyclopropane-1-carboxylate also induced high levels of antifreeze activity at 20°C, and this effect could be blocked by the ethylene inhibitor AgNO3. When intact rye plants were exposed to 5°C, endogenous ethylene production and antifreeze activity were detected within 12 and 48 h of exposure to cold, respectively. Rye plants exposed to drought produced both ethylene and antifreeze activity within 24 h. We conclude that ethylene is involved in regulating antifreeze activity in winter rye in response to cold and drought.

Yu, Xiao-Ming; Griffith, Marilyn; Wiseman, Steven B.

2001-01-01

313

An anthropogenic signal in Phoenix, Arizona winter precipitation  

NASA Astrophysics Data System (ADS)

Many other investigators have shown pronounced weekly cycles in atmospheric composition, particularly in large urban settings. A substantial body of literature shows that the varying concentrations of fine atmospheric aerosols (particulate matter (PM)2.5) impact precipitation processes; generally, higher concentrations of these aerosols tend to depress winter precipitation especially in short-lived, shallow, and orographic clouds. Phoenix, Arizona has a large population relying heavily on motor vehicles as the primary means of transportation. This results in a strong weekly cycle of PM2.5 concentrations with a maximum on Wednesday and Thursday and a distinctive minimum on the weekend. To determine any influence on rainfall, we analyze daily precipitation records from 291 stations in the Phoenix area and find a strong weekly cycle in winter precipitation frequencies with maximum values on Sunday and minimum values on Thursday. The weekly cycle in precipitation frequency strengthens slightly moving eastward (downwind) across the metropolitan area as well as with increasing proximity to the metropolitan area. These results strongly suggest that human activity is influencing winter precipitation primarily by the suppressing effect of PM2.5.

Svoma, Bohumil M.; Balling, Robert C.

2009-10-01

314

Winter survival of Eurasian woodcock Scolopax rusticola in central Italy  

USGS Publications Warehouse

The Eurasian woodcock Scolopax rusticola is a popular game bird in much of Europe. However, little is known about its population dynamics. We estimated winter survival of woodcock in a protected area with no hunting in central Italy. We radio-tagged 68 woodcocks with battery-powered radio-transmitters during 2001-2005. Woodcocks were captured in fields at night from November through February and fitted with radios. Birds were classified on capture as juveniles or adults using plumage characteristics. Woodcocks were relocated daily through March of each year or until they died, disappeared from the study area, or until their radio failed. We constructed a set of eight competing models of daily survival for the period 1 December - 28 February. Estimates of survival were obtained using the program SURVIV and Akaike's Information Criteria. The best model suggested daily survival was a constant 0.9985 (95% CI = 0.9972-0.9998), corresponding to a survival rate of 0.88 (SE = 0.05) for the 90-day winter study period. Our estimate of juvenile survival is higher than previously reported, and may reflect the protected status of the study area. Our estimates of winter survival may be helpful in managing harvested woodcock populations as well as in conserving populations in an increasingly urbanised environment. ?? Wildlife Biology (2008).

Aradis, A.; Miller, M. W.; Landucci, G.; Ruda, P.; Taddei, S.; Spina, F.

2008-01-01

315

Nuclear winter: the implications for civil defense  

SciTech Connect

It is generally believed possible for some range of heavy nuclear attacks directed against cities that significant but not lethal climate alteration will ensue for at least a few weeks. Three-dimensional global circulation models being developed and used at Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), and the National Center for Atmospheric Research for a reasonable attack size seem to be converging on a temperature depression of the order of 10 to 15/degree/C, averaged over all land areas of the temperate region of the northern hemisphere. Temperature depressions as large as 25/degree/C are predicted in the interiors of continents for attacks in the summertime. Winter wars produce temperature depressions of only a few degrees. The authors have drawn the following implications for civil defense of the possibility of nuclear winter: (1) Neither cold nor drought is likely to be a direct threat to human survival. (2) The principal threat of nuclear winter is to agriculture. (3) Nuclear winter does not present an entirely new threat from nuclear war to the United States or the Soviet Union. (4) The consequences of nuclear winter would fall more heavily on the Soviet Union.

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

1987-01-01

316

Frequency of Upward Lightning Hits to Wind Turbines in Winter  

NASA Astrophysics Data System (ADS)

In recent years, frequent damages of wind turbines by winter lightning have been reported in the region along the Sea of Japan. It is a serious finding that lightning hits concentrate on wind turbines in this region. The authors investigated the rate of increased frequency of lightning hits on wind turbines due to its construction by using LLS (Lightning Location System) data. As a result, an experimental formula to estimate the increase rate of the frequency of lightning hits on wind turbines as a function of parameters related to the construction condition, namely the height of wind turbines, the height above the sea level and the latitude, is proposed.

Saito, Mikihisa; Ishii, Masaru; Ohnishi, Atsushi; Fujii, Fumiyuki; Matsui, Michihiro; Natsuno, Daisuke

317

Lesser scaup winter foraging and nutrient reserve acquisition in east-central Florida  

USGS Publications Warehouse

Lesser scaup (Aythya affinis) populations have been declining since the late 1970s. One of the explanations to account for this decline, the spring-condition hypothesis (SCH), is based on the premise that scaup are limited by their ability to acquire or maintain nutrient reserves during migration to the breeding grounds, leading to an impairment of their reproductive potential. Available evidence suggests that endogenous reserves required for reproduction are obtained at a later stage of migration or after arrival at the breeding grounds, not wintering sites. However, only one study has addressed body-condition levels on a southern wintering site in the last decade, with results limited to the wintering grounds on the Mississippi Flyway. We documented foraging behavior, nutrient levels, and body mass of lesser scaup in east-central Florida, USA, where 62% of the Atlantic Flyway population overwinters, during the winters of 2002 and 2003. Diurnal foraging did not increase seasonally. Nocturnal foraging increased seasonally by 76% or 43 minutes per night in females and by 478% or 1.9 hours per night in males. Measures of body condition did not change seasonally during 2002 for either sex. Between early and later winter in 2003 corrected body mass (CBM) and lipid reserves of male scaup increased 77 g and 39 g, respectively. Our results suggest that lesser scaup maintain or may slightly improve their physiological condition in east-central Florida during winter. Lower body mass and differences in nutrient levels in east-central Florida, compared to a wintering site in Louisiana, likely stem from geographic variation and lower thermal requirements associated with the warmer Florida environment. Lesser scaup depart Florida with sufficient reserves to initiate spring migration, but they maximize nutrient reserves used during reproduction elsewhere during migration or on the breeding grounds. These results suggest that maintaining the ecological integrity of this wintering ground is critical in minimizing winter mortality and preventing it from becoming an ancillary factor in current declines. Future research should address understanding survival rates during spring migration and at critical staging areas to provide new insight into the ramifications of scaup leaving wintering habitats such as MINWR with lower body condition than at other wintering sites in other flyways.

Herring, G.; Collazo, J. A.

2006-01-01

318

Rapid climate driven shifts in wintering distributions of three common waterbird species.  

PubMed

Climate change is predicted to cause changes in species distributions and several studies report margin range shifts in some species. However, the reported changes rarely concern a species' entire distribution and are not always linked to climate change. Here, we demonstrate strong north-eastwards shifts in the centres of gravity of the entire wintering range of three common waterbird species along the North-West Europe flyway during the past three decades. These shifts correlate with an increase of 3.8 °C in early winter temperature in the north-eastern part of the wintering areas, where bird abundance increased exponentially, corresponding with decreases in abundance at the south-western margin of the wintering ranges. This confirms the need to re-evaluate conservation site safeguard networks and associated biodiversity monitoring along the flyway, as new important wintering areas are established further north and east, and highlights the general urgency of conservation planning in a changing world. Range shifts in wintering waterbirds may also affect hunting pressure, which may alter bag sizes and lead to population-level consequences. PMID:23509023

Lehikoinen, Aleksi; Jaatinen, Kim; Vähätalo, Anssi V; Clausen, Preben; Crowe, Olivia; Deceuninck, Bernard; Hearn, Richard; Holt, Chas A; Hornman, Menno; Keller, Verena; Nilsson, Leif; Langendoen, Tom; Tománková, Irena; Wahl, Johannes; Fox, Anthony D

2013-04-18

319

Winter weather versus group thermoregulation: what determines survival in hibernating mammals?  

PubMed

For socially hibernating mammals, the effectiveness of huddling as a means of energy conservation should increase with group size. However, group size has only been linked to increased survival in a few hibernating species, and the relative importance of social structure versus winter conditions during hibernation remains uncertain. We studied the influence of winter weather conditions, social group composition, age-structure, and other environmental factors and individual attributes on the overwinter survival of hoary marmots (Marmota caligata) in the Yukon Territory, Canada. Juvenile hoary marmot survival was negatively correlated with the mean winter (November to May) Pacific Decadal Oscillation (PDO) index. Survival in older age-classes was negatively correlated with PDO lagged by 1 year. Social group size and structure were weakly correlated with survival in comparison to PDO. The relationship between winter PDO and survival was most likely due to the importance of snowpack as insulation during hibernation. The apparent response of hoary marmots to changing winter conditions contrasted sharply with those of other marmot species and other mammalian alpine herbivores. In conclusion, the severity of winter weather may constrain the effectiveness of group thermoregulation in socially hibernating mammals. PMID:23456241

Patil, V P; Morrison, S F; Karels, T J; Hik, D S

2013-03-03

320

Nuclear winter: the continuing debate. Student essay  

SciTech Connect

This essay examines the debate over the climatic consequences of global nuclear war as related in the so-called Nuclear Winter hypothesis. This review examines the major components of the theory and traces development of the scientific knowledge leading to a second phase of the controversy two years after the first hypothesis. The conclusions of the essay are that the original nuclear winter findings have been altered by later scientific study and, therefore, the political conclusions drawn by Carl Sagan in 1983 can no longer be supported by theory or facts. Continued use of the Crutzen-Birks (Ambio, 1982) and TTAPS (Science, December 1983) studies worst-case evidence from NCAR (Foreign Affairs, Summer 86) represents selective science. Arguing for strategic policy changes based on nuclear winter risks constitutes anti-nuclear rhetoric and not scientific reasoning.

Nida, A.V.

1987-03-23

321

Climate Change Impacts on Winter and Spring Runoff and Recharge in Wisconsin  

NASA Astrophysics Data System (ADS)

Our research seeks to quantify the impacts of warming winter temperatures and increased winter precipitation on water resources in Wisconsin. We are currently working to calibrate a Precipitation-Runoff Modeling System (PRMS) model of the Black Earth Creek Watershed, and will be using a newly-created frost module to examine the impacts of warming winter temperatures on winter and spring infiltration. As a class 1 trout stream, Black Earth Creek is of particular interest as a sensitive and economically important natural resource. Research carried out over 2010 utilized a one-dimensional soil model (Simultaneous Heat and Water, or SHAW) that simulates heat and water fluxes as well as frost processes. This model was driven by climate data obtained from a set of statistically-downscaled and de-biased General Circulation Model (GCM) data for historic and projected future for the years 2046-2065 and 2081-2100 under the SRES A1B emissions scenario. This research suggested that warming temperatures and reduced snow cover, along with a projected increase in winter precipitation, would lead to decreased soil frost formation and a commensurate increase in winter and spring infiltration and recharge. The one-dimensional structure of the model, however, made it difficult to calibrate at the landscape scale, as it is fundamentally unable to replicate the complex spatial processes that are critically important to hydrologic response. We hope that the PRMS model, driven with the same modeled climatic data, will be able to confirm the results of our SHAW modeling; namely that winter and spring recharge will increase significantly in a warming climate. Such an increase in recharge could have profound impacts on Wisconsin fisheries, agriculture, and development.

Murdock, E. A.; Potter, K. W.

2011-12-01

322

Harsh European winters linked to sunspot minima  

NASA Astrophysics Data System (ADS)

The Rhine, one of central Europe's largest rivers, freezes only during the coldest winters. Between 1780 and 1963, the Rhine froze over in several places 14 times; 10 of those occurred when the number of sunspots was at a minimum, a new study finds. Combining historical records, primarily annual dock accounts that documented instances when icy waters hampered shipping along the Rhine during the nineteenth and twentieth centuries, Sirocko et al. determined that freezing episodes—a proxy for the harshest central European winters over the past 263 years—are statistically tied to the minima of the 11-year cycles in sunspot activity.

Bhattacharya, Atreyee

2012-11-01

323

Metabolic and Ultrastructural Changes in Winter Wheat during Ice Encasement Under Field Conditions 1  

PubMed Central

The effect of ice encasement on the physiological, metabolic, and ultrastructural properties of winter wheat (Triticum aestivum L.) grown under field conditions was examined by artificially encasing winter wheat in ice during early winter. Cold hardiness and survival of ice-encased seedlings declined less rapidly in Kharkov, a cold-hardy cultivar than in Fredrick, a less hardy cultivar. Ethanol did not accumulate in non-iced seedlings, but increased rapidly upon application of an ice sheet. Lactic acid accumulated in both cultivars during late autumn, prior to ice encasement, and elevated levels of lactic acid were maintained throughout the winter in seedlings from both iced and non-iced plots. The rate of O2 consumption of shoot tissue of seedlings from non-iced plots remained relatively constant throughout the winter, but declined rapidly in seedlings from ice encased plots. Major ultrastructural changes did not occur in shoot apex cells of non-iced winter wheat seedlings during cold hardening under field conditions. However, the imposition of an ice cover in early January resulted in a proliferation of the endoplasmic reticulum membrane system of the cells, frequently resulting in the formation of concentric whorls of membranes, often enclosing cytoplasmic organelles. Electrondense areas within the cytoplasm which appeared to be associated with the expanded endoplasmic reticulum were also frequently observed. ImagesFIG. 3FIG. 4FIG. 5FIG. 6FIG. 7FIG. 8

Pomeroy, M. Keith; Andrews, Christopher J.

1978-01-01

324

Does Day Length Affect Winter Bird Distribution? Testing the Role of an Elusive Variable  

PubMed Central

Differences in day length may act as a critical factor in bird biology by introducing time constraints in energy acquisition during winter. Thus, differences in day length might operate as a main determinant of bird abundance along latitudinal gradients. This work examines the influence of day length on the abundance of wintering crested tits (Lophophanes cristatus) in 26 localities of Spanish juniper (Juniperus thurifera) dwarf woodlands (average height of 5 m) located along a latitudinal gradient in the Spanish highlands, while controlling for the influence of food availability, minimum night temperature, habitat structure and landscape characteristics. Top regression models in the AIC framework explained 56% of variance in bird numbers. All models incorporated day length as the variable with the highest magnitude effect. Food availability also played an important role, although only the crop of ripe juniper fruits, but not arthropods, positively affected crested tit abundance. Differences in vegetation structure across localities had also a strong positive effect (average tree height and juniper tree density). Geographical variation in night temperature had no influence on crested tit distribution, despite the low winter temperatures reached in these dwarf forests. This paper demonstrates for the first time that winter bird abundance increases with day length after controlling for the effect of other environmental variables. Winter average difference in day length was only 10.5 minutes per day along the 1°47? latitudinal interval (190 km) included in this study. This amount of time, which reaches 13.5 h accumulated throughout the winter season, appears to be large enough to affect the long-term energy budget of small passerines during winter and to shape the distribution of winter bird abundance under restrictive environmental conditions.

Carrascal, Luis M.; Santos, Tomas; Telleria, Jose L.

2012-01-01

325

Simulating the influences of various fire regimes on caribou winter habitat  

USGS Publications Warehouse

Caribou are an integral component of high-latitude ecosystems and represent a major subsistence food source for many northern people. The availability and quality of winter habitat is critical to sustain these caribou populations. Caribou commonly use older spruce woodlands with adequate terrestrial lichen, a preferred winter forage, in the understory. Changes in climate and fire regime pose a significant threat to the long-term sustainability of this important winter habitat. Computer simulations performed with a spatially explicit vegetation succession model (ALFRESCO) indicate that changes in the frequency and extent of fire in interior Alaska may substantially impact the abundance and quality of winter habitat for caribou. We modeled four different fire scenarios and tracked the frequency, extent, and spatial distribution of the simulated fires and associated changes to vegetation composition and distribution. Our results suggest that shorter fire frequencies (i.e., less time between recurring fires) on the winter range of the Nelchina caribou herd in eastern interior Alaska will result in large decreases of available winter habitat, relative to that currently available, in both the short and long term. A 30% shortening of the fire frequency resulted in a 3.5-fold increase in the area burned annually and an associated 41% decrease in the amount of spruce-lichen forest found on the landscape. More importantly, simulations with more frequent fires produced a relatively immature forest age structure, compared to that which currently exists, with few stands older than 100 years. This age structure is at the lower limits of stand age classes preferred by caribou from the Nelchina herd. Projected changes in fire regime due to climate warming and/or additional prescribed burning could substantially alter the winter habitat of caribou in interior Alaska and lead to changes in winter range use and/or population dynamics. ?? 2006 by the Ecological Society of America.

Rupp, T. S.; Olson, M.; Adams, L. G.; Dale, B. W.; Joly, K.; Henkelman, J.; Collins, W. B.; Starfield, A. M.

2006-01-01

326

The Colgate University Winter Wilderness Survival Program.  

ERIC Educational Resources Information Center

|In January 1976, Colgate University offered its first Winter Wilderness Survival Program in conjunction with the North American Wilderness Survival School (NAWSS). This post-program evaluation summarizes background of the three-week program, with attention to the leadership, program aims, how the course was publicized, and how it developed month…

Haskell, Peter C.; Milner, Robert

327

Nuclear winter from gulf war discounted  

Microsoft Academic Search

Would a major conflagration in Kuwait's oil fields trigger a climate catastrophe akin to the 'nuclear winter' that got so much attention in the 1980s This question prompted a variety of opinions. The British Meteorological Office and researchers at Lawrence Livermore National Laboratory concluded that the effect of smoke from major oil fires in Kuwait on global temperatures is likely

E. MARSHALL

1991-01-01

328

Overview of Climatic Effects of Nuclear Winter.  

National Technical Information Service (NTIS)

A general description of the climatic effects of a nuclear war are presented. This paper offers a short history of the subject, a discussion of relevant parameters and physical processes, and a description of plausible nuclear winter scenario. 9 refs. (ER...

E. M. Jones R. C. Malone

1985-01-01

329

Coming to grips with nuclear winter  

Microsoft Academic Search

This editorial examines the politics related to the concept of nuclear winter which is a term used to describe temperature changes brought on by the injection of smoke into the atmosphere by the massive fires set off by nuclear explosions. The climate change alone could cause crop failures and lead to massive starvation. The author suggests that the prospect of

Scherr

1985-01-01

330

Nuclear winter: the continuing debate. Student essay  

Microsoft Academic Search

This essay examines the debate over the climatic consequences of global nuclear war as related in the so-called Nuclear Winter hypothesis. This review examines the major components of the theory and traces development of the scientific knowledge leading to a second phase of the controversy two years after the first hypothesis. The conclusions of the essay are that the original

Nida

1987-01-01

331

HARVESTING WINTER FORAGES TO EXTRACT MANURE NUTRIENTS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Harvested hay captures soil manure nutrients which, if not utilized, could cause pollution of surface water or aquifer. This study determined yields of hay and N,P,K,Mg,Mn,Ca,Fe,Zn, and Cu of three winter forages in five harvesting systems. Dormant bermudagrass [Cynodon dactylon (L.)Pers.] sod regul...

332

IMPACT OF OZONE ON WINTER WHEAT YIELD  

EPA Science Inventory

Wheat is one of the more important agricultural crops in the USA, and the major production areas may be subjected to potentially damaging concentrations of ozone (O3). Since no information was available regarding the O3 sensitivity of winter wheat cultivars grown in the Midwest, ...

333

INTERCROPPING WINTER CEREAL GRAINS AND RED CLOVER  

Technology Transfer Automated Retrieval System (TEKTRAN)

Energy, economic, environmental, and pest issues are leading some crop producers to diversity beyond the corn/soybean rotation dominant in Iowa. Research by Iowa State University and the United States Department of Agriculture’s National Soil Tilth Laboratory indicates intercropping of winter cereal...

334

Lake Erie Ice: Winter 1975-76.  

National Technical Information Service (NTIS)

Ice conditions on Lake Erie depicted mainly from satellite imagery were observed during the winter of 1975-76. The formation, movement, and decay of lake ice were traced at intervals of about 3 days from December 28, 1975, to April 19, 1976. Wind speeds a...

J. H. Wartha

1977-01-01

335

CBS Sportsline: The XVII Winter Olympic Games  

NSDL National Science Digital Library

The 18th Winter Olympic Games will be held at Nagano, Japan from February 7 to February 22, 1998. CBS TV is the American network broadcasting the games and its site is highlighted by feature stories about each sport, a schedule of events, rules, and brief individual profiles.

1998-01-01

336

Hulless winter barley for ethanol production  

Technology Transfer Automated Retrieval System (TEKTRAN)

Hulless barley is viable feedstock alternative to corn for ethanol production in areas where small grains are produced. The first barley-based ethanol plant in the US is currently under construction by Osage BioEnergy LLC in Hopewell, VA. New hulless winter barley varieties developed by Virginia T...

337

Registration of Anton Hard White Winter Wheat  

Technology Transfer Automated Retrieval System (TEKTRAN)

‘Anton’ (Reg. No. CV PI 651043) hard white winter wheat (Triticum aestivum L.) was developed by the USDA-ARS and the Nebraska Agricultural Experiment Station and released in December, 2007. "Anton" was selected from the cross WA691213-27/N86L177//‘Platte’. Anton primarily was released for its lo...

338

Myths of mid-winter depression  

Microsoft Academic Search

An investigation was conducted into the effect of a major Alaskan annual winter festival upon the rates of crisis data. Analysis of rates of suicide, attempted suicide, family disturbance calls, crisis calls, and mental health admissions indicated no significant effect of the festival. Statewide statistics over several years indicate that demands for depression-related services appear to peak in either the

Russ Christensen; Peter W. Dowrick

1983-01-01

339

Outing Activities and Winter Sports Guide.  

ERIC Educational Resources Information Center

|This guide contains articles on outdoor recreational activities and official winter sports rules for girls and women. The articles on outdoor activities include the techniques, teaching, and organization of camping, canoeing, competitive cycling, and riflery. Four pages of references on nature and outdoor activities are presented along with two…

Knierim, Helen, Ed.; Hobson, Barbara B., Ed.

340

DEVELOPMENT AND CHARACTERIZATION OF WAXY WINTER WHEATS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Waxy grain crops produce endosperm starch lacking amylose and consisting only of amylopectin. Such starch is formed when mutations are present that eliminate the production, or function, of an enzyme known as the granule-bound starch synthase, (GBSS, or the “waxy protein”). Waxy winter wheat...

341

STORAGE PROTEINS IN WINTER HONEY BEES  

Microsoft Academic Search

Honey bee colonies in temperate climates begin brood rearing in late winter before floral resources are available. Protein required for brood rearing comes from pollen stored in combs as well as proteins stored internally in the bees' bodies. We studied the changes in amounts of several proteins that could serve as internal storage compounds in fall-emerging bees that contributed to

G. W. Otis; D. E. Wheeler; N. Buck; H. R. Mattila

2004-01-01

342

Registration of 'Windham' Winter Feed Pea.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Winter legumes offer a unique opportunity for producers to establish a legume crop in the fall and transfer a significant portion of field preparation to the fall avoiding undesirable field conditions in the spring, and yet maintain the benefits of including a legume in the crop rotation. ‘Windham’ ...

343

PPMCSA Presentation on Winter Distillate Outlook  

NSDL National Science Digital Library

This presentation on the Winter Distillate Outlook was created for the PPMCSA Meeting and Trade Show of this year. It gives basic information and forecasts on the prices of a variety of energy sources through a collection of slides and accompanying notes.

344

Appalachia's Winter Secret: Downhill on the Mountains.  

ERIC Educational Resources Information Center

Describes ski-industry and winter-tourism growth in Appalachia. Sketches ski-resort developments in Maryland, Pennsylvania, North Carolina, and West Virginia. Describes economic threats to industry, its economic impact on Appalachian states and region, resorts' general qualities, and ski industry's promotional efforts. (TES)

Johnson, Randy

1991-01-01

345

Soviet Exploitation of the 'Nuclear Winter' Hypothesis.  

National Technical Information Service (NTIS)

This study, which is based entirely on open Soviet sources, examines and analyzes Soviet views on and uses made by Soviet scientists of the so-called ''Nuclear Winter'' hypothesis. In particular, the study seeks to ascertain whether Soviet scientists have...

L. Goure

1985-01-01

346

Infrared issues for the nuclear winter phenomenon  

Microsoft Academic Search

Simple models of the nuclear winter phenomenon are used to study the possibility that the infrared radiators: hydrocarbons, carbon dioxide, nitrogen dioxide, H2O or condensed water (clouds), might have important effects. Most of these substances are found to be unimportant but water clouds, if they are present and it appears they might be, are found to be of great potential

G. McCartor; D. Archer; W. Wortman; T. Old

1985-01-01

347

Some policy implications of nuclear winter  

Microsoft Academic Search

The theory of nuclear winter has had as checkered a history as any new idea since Darwin published The Origin of Species. There have been questions of its scientific validity, reviews both laudatory and damning, pleas for arms reductions, hosannahs for a newfound hope that nuclear war has at least been rendered completely unthinkable, and frustration that two generations of

Gertler

1985-01-01

348

Mate loss in winter and mallard reproduction  

USGS Publications Warehouse

Mallards (Anas platyrhynchos) frequently pair during winter, and duck hunting seasons have been extended until the end of January in several southern states in the Mississippi Flyway. Therefore, we simulated dissolution of pair bonds from natural or hunting mortality by removing mates of wild-strain, captive, yearling female mallards in late January 1996 and early February 1997 to test if mate loss in winter would affect subsequent pair formation and reproductive performance. Most (97%) widowed females paired again. Nesting and incubation frequencies, nest-initiation date, days between first and second nests, and egg mass did not differ (P > 0.126) between widowed and control (i.e., no mate loss experienced) females in 1996 and 1997. In 1997, widowed females laid 1.91 fewer eggs in first nests (P = 0.014) and 3.75 fewer viable eggs in second nests (P = 0.056). Computer simulations with a mallard productivity model (incorporating default parameters [i.e., average environmental conditions]) indicated that the observed decreased clutch size of first nests, fewer viable eggs in second nests, and these factors combined had potential to decrease recruitment rates of yearling female mallards 9%, 12%, and 20%. Our results indicate that winter mate loss could reduce reproductive performance by yearling female mallards in some years. We suggest caution regarding extending duck hunting seasons in winter without concurrent evaluations of harvest and demographics of mallard and other duck populations.

Lercel, B. A.; Kaminski, R. M.; Cox, R. R., Jr.

1999-01-01

349

Registration of 'Dan' winter hulless barley  

Technology Transfer Automated Retrieval System (TEKTRAN)

Dan’ (Reg. No. CV- , PI 659066) six-rowed winter hulless barley (Hordeum vulgare L.) was developed and released by the Virginia Agricultural Experiment Station in March 2009. Dan was derived from the cross VA96-41-17 / SC872143. It was released for production in the eastern United States, as a poten...

350

Probabilistic Weather Forecasting for Winter Road Maintenance.  

National Technical Information Service (NTIS)

Road maintenance is one of the main problems Departments of Transportation face during winter time. Anti-icing, i.e. applying chemicals to the road to prevent ice formation, is often used to keep the roads free of ice. Given the preventive nature of anti-...

V. J. Berrocal A. Raftery T. Gneiting R. C. Steed

2007-01-01

351

PLCO News, Fall/Winter 1998  

Cancer.gov

PLCO News, Fall/Winter 1998 Volume 2, Number 1 ----- Spring/Summer 1999 Trial Update Enrollment goal: 148,000 Total enrollment (as of March 15, 1999): 121,027 Men enrolled: 62,409 Women enrolled: 58,618 Number of people enrolled

352

PLCO News, Fall/Winter 1998  

Cancer.gov

PLCO News, Fall/Winter 1998 Volume 3, Number 1 ----- Spring/Summer 2000 Trial Update Enrollment goal: 148,000 Total enrollment (as of December 29, 1999): 138,847 Men enrolled: 69,990 Women enrolled: 68,857 Number of people enrolled

353

Effects of winter atmospheric circulation on temporal and spatial variability in annual streamflow in the western United States  

USGS Publications Warehouse

Winter mean 700-hectoPascal (hPa) height anomalies, representing the average atmospheric circulation during the snow season, are compared with annual streamflow measured at 140 streamgauges in the western United States. Correlation and anomaly pattern analyses are used to identify relationships between winter mean atmospheric circulation and temporal and spatial variability in annual streamflow. Results indicate that variability in winter mean 700-Hpa height anomalies accounts for a statistically significant portion of the temporal variability in annual streamflow in the western United States. In general, above-average annual streamflow is associated with negative winter mean 700-Hpa height anomalies over the eastern North Pacific Ocean and/or the western United States. The anomalies produce an anomalous flow of moist air from the eastern North Pacific Ocean into the western United States that increases winter precipitation and snowpack accumulations, and subsequently streamflow. Winter mean 700-hPa height anomalies also account for statistically significant differences in spatial distributions of annual streamflow. As part of this study, winter mean atmospheric circulation patterns for the 40 years analysed were classified into five winter mean 700-hPa height anomaly patterns. These patterns are related to statistically significant and physically meaningful differences in spatial distributions of annual streamflow.

McCabe, Jr. , G. J.

1996-01-01

354

Nuclear Winter: Implications for civil defense  

SciTech Connect

''Nuclear Winter'' is the term given to the cooling hypothesized to occur in the Northern Hemisphere following a nuclear war as the result of the injection of smoke from burning cities into the atmosphere. The voluminous literature on this subject produced since the paper was published in 1983 by Turco, Toon, Ackerman, Pollack, and Sagen (TTAPS) has been reviewed. Three-dimensional global circulation models have resulted in reduced estimates of cooling---15 to 25/degree/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 is likely to be a direct threat to human survival for populations with the wherewithal to survive normal January temperatures. The principal threat from nuclear winter is to food production, and this could present problems to third parties who are without food reserves. Loss of a crop year is neither a new nor an unexpected threat from nuclear war to the United States 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 United States 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.

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

1988-05-01

355

Cryopreservation of winter-dormant apple buds: I -Variation in recovery with cultivar and winter conditions.  

PubMed

The widely-adopted protocol for the cryopreservation of winter buds of fruit trees, such as Malus and Pyrus, was developed in a region with a continental climate, that provides relatively hard winters with a consequent effect on adaptive plant hardiness. In this study the protocol was evaluated in a typical maritime climate (eastern Denmark) where milder winters can be expected. The survival over two winters was evaluated, looking at variation between seasons and cultivars together with the progressive reduction in survival due to individual steps in the protocol. The study confirms that under such conditions significant variation in survival can be expected and that an extended period of imposed dehydration at -4 degree C is critical for bud survival. The occurrence of freezing events during this treatment suggests that cryodehydration may be involved, as well as evaporative water loss. To optimize the protocol for maritime environments, further investigation into the water status of the explants during cryopreservation is proposed. PMID:22020415

Vogiatzi, C; Grout, B W W; Wetten, A; Toldam-Andersen, T B

356

Winter food availability limits winter survival of Mongolian gerbils ( Meriones unguiculatus )  

Microsoft Academic Search

Food availability is important to the dynamics of animal social organizations or populations. However, the role of winter\\u000a food availability in animal population dynamics is still controversial. We carried out an experimental study to test Lack’s\\u000a hypothesis that reduced food in winter limits survival and spring numbers of breeding individuals of social groups, using\\u000a the Mongolian gerbil (Meriones unguiculatus) as

Wei Liu; Guiming Wang; Xinrong Wan; Wenqin Zhong

2011-01-01

357

Beat the Winter Blues: Shedding Light on Seasonal Sadness  

MedlinePLUS

... Issue This Issue Features Beat the Winter Blues Radon Risk Health Capsules Trust Rises With Age Salivary ... select search option Features Beat the Winter Blues Radon Risk Wise Choices Links Lift Your Mood These “ ...

358

NEW RECORDS OF WINTER STONEFLIES (PLECOPTERA: CAPNIIDAE) IN MISSISSIPPI  

Microsoft Academic Search

New Mississippi distribution records, based on 2007-2008 and 2008-2009 winter collections are presented for seven of the eight species of winter stoneflies (Family Capniidae) known to occur in the state.

Bill P. Stark; Matthew B. Hicks

359

Chaperone proteins and winter survival by a freeze tolerant insect.  

PubMed

The role of chaperone proteins in the winter survival of insects was evaluated in freeze tolerant gall fly larvae, Eurosta solidaginis. Levels of four heat shock proteins (Hsp110, Hsp70, Hsp60, Hsp40), two glucose-regulated proteins (Grp75, Grp78) and three others (tailless complex polypeptide 1 [TCP-1], ?A-crystallin, ?B-crystallin) were tracked in outdoor larvae from September to April and, in addition, laboratory experiments assessed chilling, freezing, and anoxia effects on these proteins. Gall fly larvae showed consistent elevation of Hsp110, Hsp70, Hsp40, Grp78 and ?B-crystallin over the late autumn and winter months, generally 1.5-2.0-fold higher than September values. This suggests that these proteins contribute to cell preservation over the winter months via protection and stabilization of macromolecules. By contrast, levels of the mitochondrial Hsp60 fell to just 40% of September values by midwinter, paralleling the responses by numerous mitochondrial enzymes and consistent with a reduction in total mitochondria numbers over the winter. None of the proteins were altered when 15°C acclimated larvae were chilled to 3°C for 24h but Hsp70, Hsp40 and Grp75 increased during freezing at -16°C for 24h whereas others (Hsp110, TCP-1 and both crystallins) increased significantly after larvae thawed at 3°C. Anoxia exposure (24h under N2 gas at 15°C) elevated levels of Hsp70, Grp78 and the two crystallins. Levels of active hyperphosphorylated heat shock transcription factor (HSF1) were also analyzed, giving an indication of the state of hsp gene transcription in the larvae. HSF1 was high in September and October but fell to less than 40% of September values in midwinter consistent with suppression of gene transcription in diapause larvae. HSF1 levels responded positively to freezing and increased robustly by 4.9-fold under anoxia. Overall, the data provide strong evidence for the importance of protein chaperones as a mechanism of cell preservation in freeze tolerant insects. PMID:21382374

Zhang, Guijun; Storey, Janet M; Storey, Kenneth B

2011-03-04

360

Simulating the winter North Atlantic Oscillation: the roles of internal variability and greenhouse gas forcing  

Microsoft Academic Search

Analysis of simulations with seven coupled climate models demonstrates that the observed variations in the winter North Atlantic Oscillation (NAO), particularly the increase from the 1960s to the 1990s, are not compatible with either the internally generated variability nor the response to increasing greenhouse gas forcing simulated by these models. The observed NAO record can be explained by a combination

T. J. Osborn

2004-01-01

361

Impacts of Convective Gravity Wave Drag in the Southern Hemisphere Winter Stratosphere  

NASA Astrophysics Data System (ADS)

Excessive cold pole and stronger polar vortex in the southern hemisphere (SH) winter stratosphere are the long-lasting problem in most general circulation models (GCMs). Recent studies show that this problem is related to the underestimated model wave drag in the SH winter extratropical stratosphere, especially by underestimated or missing gravity wave drag (GWD) in the SH. Convective GWD is one of the major missing GWDs in most current GCMs that could significantly influence on the temperature and polar vortex in the SH winter stratosphere. Cumulus convection is strong in the storm track regions of the winter extratropics as well as in the tropics, and thus convectively induced gravity waves provide substantial wave drag in the SH winter stratosphere. The non-orographic GWD parameterizations that do not consider specific sources may not realistically represent the GWD in those specific regions. In this study, we use the Whole Atmosphere Community Climate Model (WACCM) and show that the temperature and wind biases in the SH winter stratosphere of the model in the June-August (JJA) climatology are significantly alleviated by including two convective gravity wave drag (GWDC) parameterizations (a columnar scheme and a ray-based scheme). The reduction in the wind biases is due to directly the addition of GWDC in the SH midlatitudes and indirectly the enhanced resolved wave drag in response to GWDC. The enhanced wave drag also improves the springtime breakdown of the SH vortex that delayed in the simulation without GWDC. The cold temperature biases are alleviated by increased downwelling in the SH winter polar regions, which stems from an increased poleward motion due to the enhanced wave drag in the midlatitudes.

Choi, H.-J.; Chun, H.-Y.

2012-04-01

362

LOW TEMPERATURE FEEDING BY WINTER-ACTIVE SPIDERS  

Microsoft Academic Search

Feeding by winter-active and winter-inactive species of spiders at low temperatures and the kinds of invertebrate prey eaten were determined. Winter-active spiders fed at 2*C, less often at -2eC and rarely at -5*C, whereas winter-inactive species displayed even more reduced feeding or none. All prey offered to the spiders were eaten except nabids, hymenopterans and the eollembolan Onyehiurus pseudoarmatus. In

C. W. Aitchison

1984-01-01

363

Invited Paper: WINTER FEEDING OF ELK IN WESTERN NORTH AMERICA  

Microsoft Academic Search

Winter feeding of elk (Cervus elaphus) is a topic that has engendered a great deal of debate among wildlife biologists, policy makers, and the general public. The first institutional feeding of elk in North America occurred inJackson Hole, Wyoming, where several thousand elk are still fed during most winters at the National Elk Refuge. Winter feeding of elk is employed

BRUCE L. SMITH

364

Livable Winter Cities--Leisure Attitudes and Activities.  

ERIC Educational Resources Information Center

|The nine articles included in this feature emphasize how leisure, recreation, health and physical activities make winter cities more livable. Specific topics include techniques for teaching about cold weather safety and cold related injuries, Arctic Winter Games, and results of a study on winter recreation in large North American communities.…

Neal, Larry; Coles, Roger, Ed.

1989-01-01

365

Chemical depletion of Arctic ozone in winter 1999\\/2000  

Microsoft Academic Search

During Arctic winters with a cold, stable stratospheric circulation, reactions on the surface of polar stratospheric clouds (PSCs) lead to elevated abundances of chlorine monoxide (ClO) that, in the presence of sunlight, destroy ozone. Here we show that PSCs were more widespread during the 1999\\/2000 Arctic winter than for any other Arctic winter in the past two decades. We have

M. Rex; R. J. Salawitch; N. R. P. Harris; P. von der Gathen; G. O. Braathen; A. Schulz; H. Deckelmann; M. Chipperfield; B.-M. Sinnhuber; E. Reimer; R. Alfier; R. Bevilacqua; K. Hoppel; M. Fromm; J. Lumpe; H. Küllmann; A. Kleinböhl; H. Bremer; M. von König; K. Künzi; D. Toohey; H. Vömel; E. Richard; K. Aikin; H. Jost; J. B. Greenblatt; M. Loewenstein; J. R. Podolske; C. R. Webster; G. J. Flesch; D. C. Scott; R. L. Herman; J. W. Elkins; E. A. Ray; F. L. Moore; D. F. Hurst; P. Romashkin; G. C. Toon; B. Sen; J. J. Margitan; P. Wennberg; R. Neuber; M. Allart; B. R. Bojkov; H. Claude; J. Davies; W. Davies; H. De Backer; H. Dier; V. Dorokhov; H. Fast; Y. Kondo; E. Kyrö; Z. Litynska; I. S. Mikkelsen; M. J. Molyneux; E. Moran; T. Nagai; H. Nakane; C. Parrondo; F. Ravegnani; P. Skrivankova; P. Viatte; V. Yushkov

2002-01-01

366

33 CFR 401.92 - Wintering and lying-up.  

Code of Federal Regulations, 2010 CFR

... 3 2010-07-01 2010-07-01 false Wintering and lying-up. 401.92 Section 401.92 Navigation and Navigable...AND RULES Regulations General § 401.92 Wintering and lying-up. No vessel shall winter within the Seaway or...

2010-07-01

367

33 CFR 401.92 - Wintering and lying-up.  

Code of Federal Regulations, 2010 CFR

... 3 2009-07-01 2009-07-01 false Wintering and lying-up. 401.92 Section 401.92 Navigation and Navigable...AND RULES Regulations General § 401.92 Wintering and lying-up. No vessel shall winter within the Seaway or...

2009-07-01

368

33 CFR 401.92 - Wintering and lying-up.  

Code of Federal Regulations, 2010 CFR

... 3 2005-07-01 2005-07-01 false Wintering and lying-up. 401.92 Section 401.92 Navigation and Navigable...AND RULES Regulations General § 401.92 Wintering and lying-up. No vessel shall winter within the Seaway or...

2005-07-01

369

33 CFR 401.92 - Wintering and lying-up.  

Code of Federal Regulations, 2010 CFR

... 3 2004-07-01 2004-07-01 false Wintering and lying-up. 401.92 Section 401.92 Navigation and Navigable...AND RULES Regulations General § 401.92 Wintering and lying-up. No vessel shall winter within the Seaway or...

2004-07-01

370

33 CFR 401.92 - Wintering and lying-up.  

Code of Federal Regulations, 2010 CFR

... 3 2001-07-01 2001-07-01 false Wintering and lying-up. 401.92 Section 401.92 Navigation and Navigable...AND RULES Regulations General § 401.92 Wintering and lying-up. No vessel shall winter within the Seaway or...

2001-07-01

371

The Science of Dystopia: A Retrospective on Nuclear Winter Modeling  

Microsoft Academic Search

This essay questions the effectiveness of nuclear winter modeling as a means of impacting nuclear policy and changing public attitudes about nuclear issues. In nuclear winter modeling, humanistic concern over the possibility of global environmental destruction is cloaked in the ostensibly neutral language of science. Nuclear winter modeling attempts to apply rational argument to an issue that is rooted instead

Howard Veregin

1994-01-01

372

Tillage Requirements for Vegetable following Winter Annual Grazing.  

National Technical Information Service (NTIS)

In Alabama, over 400,000 acres of winter annuals are grazed prior to planting summer row crops. Previous research indicates that cattle grazed on ryegrass (Lolium multiflorum L.) pastures over the winter months in Alabama can be profitable, but winter gra...

D. W. Reeves J. M. Keble K. S. Balkcom R. A. Dawkins

2009-01-01

373

Investigations of a Winter Mountain Storm in Utah. Part II: Mesoscale Structure, Supercooled Liquid Water Development, and Precipitation Processes.  

NASA Astrophysics Data System (ADS)

A comprehensive analysis of a deep winter storm system during its passage over the Tushar Mountains of southwestern Utah is reported. The case study, drawn from the 1985 Utah/NOAA cooperative weather modification experiment, is divided into descriptions of the synoptic and kinematic properties in Part I, and storm structure and composition here in Part II. In future parts of this series, the turbulence structure and indicated cloud seeding potential will be evaluated. The analysis presented here in Part II focuses on multiple remote sensor and surface microphysical observations collected from a midbarrier (2.57 km MSL) field site. The collocated remote sensors were a dual-channel microwave radiometer, a polarization lidar, and a Ka-band Doppler radar. These data are supplemented by upwind, valley-based C-band Doppler radar observations, which provided a considerably larger-scale view of the storm.In general, storm properties above the barrier were either dominated by barrier-level orographic clouds or propagating mesoscale cloud systems. The orographic cloud component consisted of weakly (3° to 10°C) supercooled liquid water (SLW) clouds in the form of an extended barrier-wide cap cloud that contained localized SLW concentrations. The spatial SLW distribution was linked to topographical features surrounding the midbarrier site, such as abrupt terrain rises and nearby ridges. This orographic cloud contributed to precipitation primarily through the riming of particles sedimenting from aloft, and also to some extent through an ice multiplication process involving graupel growth. In contrast, mesoscale precipitation bands associated with a slowly moving cold front generated much more significant amounts of snowfall. These precipitation bands periodically disrupted the shallow orographic SLW clouds. Mesoscale vertical circulations appear to have been particularly important in SLW and precipitation production along the leading edges of the bands. Since the SLW clouds during the latter part of the storm were based at the frontal boundary, SLW and precipitation gradually diminished as the barrier became submerged under the cold front.Based on a winter storm conceptual model, we conclude that low-level orographic SLW clouds, when decoupled from the overlying ice cloud layers of the storm, are generally inefficient producers of precipitation due to the typically warm temperatures at these altitudes in our region.

Sassen, Kenneth; Huggins, Arlen W.; Long, Alexis B.; Snider, Jack B.; Meitín, Rebecca J.

1990-06-01

374

Winter temperature affects the prevalence of ticks in an arctic seabird.  

PubMed

The Arctic is rapidly warming and host-parasite relationships may be modified by such environmental changes. Here, I showed that the average winter temperature in Svalbard, Arctic Norway, explained almost 90% of the average prevalence of ticks in an Arctic seabird, the Brünnich's guillemot Uria lomvia. An increase of 1°C in the average winter temperature at the nesting colony site was associated with a 5% increase in the number of birds infected by these ectoparasites in the subsequent breeding season. Guillemots were generally infested by only a few ticks (?5) and I found no direct effect of tick presence on their body condition and breeding success. However, the strong effect of average winter temperature described here clearly indicates that tick-seabird relationships in the Arctic may be strongly affected by ongoing climate warming. PMID:23750259

Descamps, Sébastien

2013-06-04

375

Winter motion mediates dynamic response of the Greenland Ice Sheet to warmer summers  

NASA Astrophysics Data System (ADS)

present ice velocities from a land-terminating transect extending >115 km into the western Greenland Ice Sheet during three contrasting melt years (2009-2011) to determine whether enhanced melting accelerates dynamic mass loss. We find no significant correlation between surface melt and annual ice flow. There is however a positive correlation between melt and summer ice displacement, but a negative correlation with winter displacement. This response is consistent with hydro-dynamic coupling; enhanced summer ice flow results from longer periods of increasing surface melting and greater duration ice surface to bed connections, while reduced winter motion is explicable by drainage of high basal water pressure regions by larger more extensive subglacial channels. Despite mean interannual surface melt variability of up to 70%, mean annual ice velocities changed by <7.5%. Increased summer melting thereby preconditions the ice-bed interface for reduced winter motion resulting in limited dynamic sensitivity to interannual variations in surface melting.

Sole, Andrew; Nienow, Peter; Bartholomew, Ian; Mair, Douglas; Cowton, Thomas; Tedstone, Andrew; King, Matt A.

2013-08-01

376

Effects of weather on habitat selection and behavior of mallards wintering in Nebraska  

USGS Publications Warehouse

Sex and age ratios, habitat selection, spatial characteristics, and time budgets of Mallards (Anas platyrhynchos) wintering on the Platte River in south central Nebraska were studied from mid-December to early April 1978-1980. The proportion of females and subadults in the population increased substantially from a cold to a mild winter. Radio-tagged Mallards shifted from riverine to canal roost sites during the coldest periods of the winter, seemingly because of more favorable microclimatic conditions there. Subadults ranged over larger areas during winter than did adults. Activity patterns varied with weather conditions, time of day, and habitat type. During cold periods, energetically costly activities such as aggression and courtship decreased at roost sites and the intensity of foraging activities in fields increased. Mallards were more active at riverine than canal sites during both years. High energy requirements and intense competition for scarce food appear to be primary factors limiting the northernmost distribution of Mallards in winter and causing their skewed sex and age ratios.

Jorde, D. G.; Krapu, G. L.; Crawford, R. D.; Hay, M. A.

1984-01-01

377

Ecology of Weddell seals during winter: Influence of environmental parameters on their foraging behaviour  

NASA Astrophysics Data System (ADS)

Studying the foraging strategies of top predators can provide information on both how animals interact with their environment and the distribution of their prey. We studied the winter foraging behaviour of Weddell seals in Adélie Land, East Antarctica, and the influence of abiotic parameters (bathymetry, hydrology, sea ice, light intensity) on their foraging behaviour. A total of six seals were fitted with Conductivity Temperature Depth Satellite Relayed Data Loggers (CTD-SRDL) at Dumont D'Urville (˜67°S, 140°E) during the austral winters in 2007 and 2008. The tags transmitted positions and dive information over 169±31 day, providing a total of 20,400 dive profiles and 2350 CTD profiles. Significant environmental influences on seal diving behaviour and habitat use were detected. Seals dived deeper, longer and increased their foraging effort during the day than at night with intermediate values for twilight. During the winter season the maximum dive depth decreased in association with an increase in dive duration, but foraging effort was unchanged. Seals spent more time at the bottom of their dives in shallow waters associated with relatively smooth bathymetry and dominated by Antarctic Surface Water. Considering the whole winter, Weddell seals tended to favour enriched, warmer and less dense water masses following their seasonal appearance on the shelf (Antarctic Surface Water and Modified Circumpolar Deep Water). Our results are consistent with seals feeding primarily on Pleuragramma antarcticum during winter, tracking their vertical diel migrations and foraging in areas associated with bathymetric and hydrographic features likely to concentrate prey patches.

Heerah, Karine; Andrews-Goff, Virginia; Williams, Guy; Sultan, Emanuelle; Hindell, Mark; Patterson, Toby; Charrassin, Jean-Benoît

2013-04-01

378

Condition of Euphausia crystallorophias off East Antarctica in winter in comparison to other seasons  

NASA Astrophysics Data System (ADS)

Antarctic coastal krill ( Euphausia crystallorophias) were collected in Austral winter (July/August) 1999 in the Mertz Glacier polynya off the coast of East Antarctica and were compared to krill collected off East Antarctica during summer in 1996 and 2001 and spring 1999. A range of experiments and measurements were conducted to assess their relative condition in winter and summer. Krill collected in winter had pale yellow-green digestive glands, indicating some recent feeding activity. The size of the digestive glands was small relative to those of krill caught in summer. This indicates that feeding had been occurring at low levels during the collection period. Growth rates, measured using the instantaneous growth rate methodology, were close to zero in winter (range -5% to 7% per moult). This was an indication that some food had been available during the period of the moult cycle. Growth rates in spring ranged from -0.5% to +8.7% per moult and from 4% to 12% per moult in the summer. The mean length of the winter moult cycle (68 days) was considerably greater than the measured intermoult period in summer and spring (24-33 days). Lipid levels were low in winter, less than 5% of body weight, compared to summer levels of ˜15% (dry weight). Winter krill were richer in wax esters and poorer in polar lipids than specimens collected in summer. Krill in winter were lacking in C16 PUFA that are markers of the phytoplankton diet common in summer krill. Krill caught in the winter had significantly higher levels of 20:1 and 22:1 fatty acids (2.3%) and alcohols (8.1%) than krill sampled in summer (0.2%, 0%), indicating a shift to a carnivorous diet. Results from this study suggest that E. crystallorophias respond to low food abundance during the winter through metabolic and physiological processes. These processes were reflected in a decrease in growth rate and a significant increase in the intermoult period. The process of lipid utilisation and switching to a carnivorous/detrital type diet are also overwintering strategies employed by this species.

Nicol, S.; Virtue, P.; King, R.; Davenport, S. R.; McGaffin, A. F.; Nichols, P.

2004-08-01

379

Winter indoor air pollution in Alaska: identifying a myth.  

PubMed

The benzene and toluene levels inside three homes with attached garages were measured for 12 consecutive weeks during the winter months in Fairbanks, Alaska (Latitude 64.5 degrees N). Results for air samples collected over 12 h for the homes showed indoor benzene mixing ratios ranging from 1.6 to 20.4 parts per billion of mixing ratio volume (ppbv), and toluene air mixing ratios ranging from 7.3 to 41.6 ppbv. A correlation between benzene and toluene levels in each home and similar regression lines suggested the same major emission source, car and small equipment gasoline, present in attached garages. In one home, there was a correlation between indoor benzene mixing ratios and the urinary biomarker, trans,trans-muconic acid. Inside, air mixing ratios of benzene and toluene decreased with decreasing outside temperature in all homes studied, even though homes were relatively tight to prevent heat loss during this period of low winter outdoor temperatures. It is suggested that buildup of these pollutants indoors is prevented by the influence of an increased indoor/outdoor temperature differential and an ensuing increase in home ventilation. PMID:11843539

Isbell, Maggie; Gordian, Mary Ellen; Duffy, Lawrence

2002-01-01

380

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

381

Impact of future warming on winter chilling in Australia  

NASA Astrophysics Data System (ADS)

Increases in temperature as a result of anthropogenically generated greenhouse gas (GHG) emissions are likely to impact key aspects of horticultural production. The potential effect of higher temperatures on fruit and nut trees' ability to break winter dormancy, which requires exposure to winter chilling temperatures, was considered. Three chill models (the 0-7.2°C, Modified Utah, and Dynamic models) were used to investigate changes in chill accumulation at 13 sites across Australia according to localised temperature change related to 1, 2 and 3°C increases in global average temperatures. This methodology avoids reliance on outcomes of future GHG emission pathways, which vary and are likely to change. Regional impacts and rates of decline in chilling differ among the chill models, with the 0-7.2°C model indicating the greatest reduction and the Dynamic model the slowest rate of decline. Elevated and high latitude eastern Australian sites were the least affected while the three more maritime, less elevated Western Australian locations were shown to bear the greatest impact from future warming.

Darbyshire, Rebecca; Webb, Leanne; Goodwin, Ian; Barlow, E. W. R.

2013-05-01

382

Observe Water in Winter and Summer  

NSDL National Science Digital Library

This short video segment depicts water in different seasons at the same location. On Earth, water can regularly be found in three different phases â liquid, solid, and gas â each of which has noticeably different properties. For example, a boat can glide through liquid water in summer, but it cannot do so when the water turns to solid ice in winter. Atmospheric conditions, specifically seasonal temperatures, can influence the phase in which water exists at a given time.

Foundation, Wgbh E.

2009-07-22

383

Tracking a Winter Storm Across the USA  

NSDL National Science Digital Library

In this activity, students track a real winter storm, collect imagery and data, perform an analysis, and make predictions on the storm's path. They will summarize their findings by writing a press release for their local radio station or by producing a report with visuals and graphics for a television broadcast. Instructions for downloading and processing data, images, and weather reports are presented along with ideas for graphing and viewing the material. Extension activities are also provided.

384

Patterns of leaf morphology and leaf N content in relation to winter temperatures in three evergreen tree species.  

PubMed

The competitive equilibrium between deciduous and perennial species in a new scenario of climate change may depend closely on the productivity of leaves along the different seasons of the year and on the morphological and chemical adaptations required for leaf survival during the different seasons. The aim of the present work was to analyze such adaptations in the leaves of three evergreen species (Quercus ilex, Q. suber and Pinus pinaster) and their responses to between-site differences in the intensity of winter harshness. We explore the hypothesis that the harshness of winter would contribute to enhancing the leaf traits that allow them to persist under conditions of stress. The results revealed that as winter harshness increases a decrease in leaf size occurs in all three species, together with an increase in the content of nitrogen per unit leaf area and a greater leaf mass per unit area, which seems to be achieved only through increased thickness, with no associated changes in density. P. pinaster was the species with the most intense response to the harshening of winter conditions, undergoing a more marked thickening of its needles than the two Quercus species. Our findings thus suggest that lower winter temperatures involve an increase in the cost of leaf production of evergreen species, which must be taken into account in the estimation of the final cost and benefit balance of evergreens. Such cost increases would be more pronounced for those species that, like P. pinaster, show a stronger response to the winter cold. PMID:21969112

Mediavilla, Sonia; Gallardo-López, Victoria; González-Zurdo, Patricia; Escudero, Alfonso

2011-10-04

385

Excess winter mortality in Europe: a cross country analysis identifying key risk factors  

PubMed Central

Objective: Much debate remains regarding why certain countries experience dramatically higher winter mortality. Potential causative factors other than cold exposure have rarely been analysed. Comparatively less research exists on excess winter deaths in southern Europe. Multiple time series data on a variety of risk factors are analysed against seasonal-mortality patterns in 14 European countries to identify key relations Subjects and setting: Excess winter deaths (all causes), 1988–97, EU-14. Design: Coefficients of seasonal variation in mortality are calculated for EU-14 using monthly mortality data. Comparable, longitudinal datasets on risk factors pertaining to climate, macroeconomy, health care, lifestyle, socioeconomics, and housing were also obtained. Poisson regression identifies seasonality relations over time. Results: Portugal suffers from the highest rates of excess winter mortality (28%, CI=25% to 31%) followed jointly by Spain (21%, CI=19% to 23%), and Ireland (21%, CI=18% to 24%). Cross country variations in mean winter environmental temperature (regression coefficient (ß)=0.27), mean winter relative humidity (ß=0.54), parity adjusted per capita national income (ß=1.08), per capita health expenditure (ß=-1.19), rates of income poverty (ß=-0.47), inequality (ß=0.97), deprivation (ß=0.11), and fuel poverty (ß=0.44), and several indicators of residential thermal standards are found to be significantly related to variations in relative excess winter mortality at the 5% level. The strong, positive relation with environmental temperature and strong negative relation with thermal efficiency indicate that housing standards in southern and western Europe play strong parts in such seasonality. Conclusions: High seasonal mortality in southern and western Europe could be reduced through improved protection from the cold indoors, increased public spending on health care, and improved socioeconomic circumstances resulting in more equitable income distribution.

Healy, J

2003-01-01

386

Effects of elevated O? exposure on nutrient elements and quality of winter wheat and rice grain in Yangtze River Delta, China.  

PubMed

With the open-top chambers (OTCs) in situ in Yangtze River Delta, China in 2007 and 2008, the effects of elevated O? exposure on nutrient elements and quality of winter wheat and rice grain were investigated. Grain yield per plant of winter wheat and rice declined in both years. The N and S concentrations increased under elevated O? exposure in both years and C-N ratios decreased significantly. The concentrations of K, Ca, Mg, P, Mn, Cu and Zn in winter wheat and the concentrations of Mg, K, Mn and Cu in rice increased. The concentrations of protein, amino acid and lysine in winter wheat and rice increased and the concentration of amylose decreased. The increase in the nutrient concentration was less than the reduction of grain yield in both winter wheat and rice, and, hence, the absolute amount of the nutrients was reduced by elevated O?. PMID:23639743

Zheng, Feixiang; Wang, Xiaoke; Zhang, Weiwei; Hou, Peiqiang; Lu, Fei; Du, Keming; Sun, Zhongfu

2013-04-29

387

Effect of canopy removal on snowpack quantity and quality, fraser experimental forest, Colorado  

USGS Publications Warehouse

Snowpack peak water equivalent (PWE), ion concentration, content, and spatial distribution of ion load data from spring 1987-1996 in a 1 ha clearcut and adjacent forested plots vegetated by mature Picea engelmannii and Abies lasiocarpa in the Fraser experimental forest (FEF), Colorado are presented. Our objectives were: (1) to see if a forest opening might redistribute snowfall, snowpack moisture, and snowpack chemical content, and (2) to examine the importance of canopy interception on snowpack quantity and chemistry. On an average, the canopy intercepted 36% of snowfall. Interception was correlated with snowfall amount, snowpack PWE beneath the canopy, and air temperature. Canopy removal increased snowpack PWE to >90% cumulative snowfall inputs. Snowpack K-, H-, and NH4+ concentrations on the clearcut were lower and NO3- higher than in the snowpack beneath the forested plots. Cu mulative snowfall K+ input was less than in the clearcut snowpack; H+ inputs were greater in snowfall than in the snowpack of any plot; and inorganic N (NO3- and NH4+) inputs from snowfall to the clearcut were greater than to the forested plots. Processes accounting for the differences between snowfall inputs and snowpack ion content were leaching of organic debris in the snowpack, differential elution of the snowpack, and canopy retention. There were significant trends by year in snowpack ion content at PWE without similar trends in snowfall inputs. This finding coupled with snowpack ion elution bring into question the use of snowpack chemistry as an indicator of winter atmospheric inputs in short-term studies. ?? 2001 Elsevier Science B.V.

Stottlemyer, R.; Troendle, C. A.

2001-01-01

388

Winter risk estimations through infrared cameras an principal component analysis  

NASA Astrophysics Data System (ADS)

Thermal mapping has been implemented since the late eighties to measure road pavement temperature along with some other atmospheric parameters to establish a winter risk describing the susceptibility of road network to ice occurrence. Measurements are done using a vehicle circulating on the road network in various road weather conditions. When the dew point temperature drops below road surface temperature a risk of ice occurs and therefore a loss of grip risk for circulating vehicles. To avoid too much influence of the sun, and to see the thermal behavior of the pavement enhanced, thermal mapping is usually done before dawn during winter time. That is when the energy accumulated by the road during daytime is mainly dissipated (by radiation, by conduction and by convection) and before the road structure starts a new cycle. This analysis is mainly done when a new road network is built, or when some major pavement changes are made, or when modifications in the road surroundings took place that might affect the thermal heat balance. This helps road managers to install sensors to monitor road status on specific locations identified as dangerous, or simply to install specific road signs. Measurements are anyhow time-consuming. Indeed, a whole road network can hardly be analysed at once, and has to be partitioned in stretches that could be done in the open time window to avoid temperature artefacts due to a rising sun. The LRPC Nancy has been using a thermal mapping vehicle with now two infrared cameras. Road events were collected by the operator to help the analysis of the network thermal response. A conventional radiometer with appropriate performances was used as a reference. The objective of the work was to compare results from the radiometer and the cameras. All the atmospheric parameters measured by the different sensors such as air temperature and relative humidity were used as input parameters for the infrared camera when recording thermal images. Road thermal heterogeneities were clearly identified, while usually missed by a conventional radiometer. In the case presented here, the two lanes of the road could be properly observed. Promising perspectives appeared to increase the measurement rate. Furthermore, to cope with the climatic constraints of the winter measurements as to build a dynamic winter risk, a multivariate data analysis approach was implemented. Principal component analysis was performed and enabled to set up of dynamic thermal signature with a great agreement between statistical results and field measurements.

Marchetti, M.; Dumoulin, J.; Ibos, L.

2012-04-01

389

Long-term variability in Northern Hemisphere snow cover and associations with warmer winters  

USGS Publications Warehouse

A monthly snow accumulation and melt model is used with gridded monthly temperature and precipitation data for the Northern Hemisphere to generate time series of March snow-covered area (SCA) for the period 1905 through 2002. The time series of estimated SCA for March is verified by comparison with previously published time series of SCA for the Northern Hemisphere. The time series of estimated Northern Hemisphere March SCA shows a substantial decrease since about 1970, and this decrease corresponds to an increase in mean winter Northern Hemisphere temperature. The increase in winter temperature has caused a decrease in the fraction of precipitation that occurs as snow and an increase in snowmelt for some parts of the Northern Hemisphere, particularly the mid-latitudes, thus reducing snow packs and March SCA. In addition, the increase in winter temperature and the decreases in SCA appear to be associated with a contraction of the circumpolar vortex and a poleward movement of storm tracks, resulting in decreased precipitation (and snow) in the low- to mid-latitudes and an increase in precipitation (and snow) in high latitudes. If Northern Hemisphere winter temperatures continue to warm as they have since the 1970s, then March SCA will likely continue to decrease. ?? 2009 Springer Science+Business Media B.V.

McCabe, G. J.; Wolock, D. M.

2010-01-01

390

Long-term variability in Northern Hemisphere snow cover and associations with warmer winters  

USGS Publications Warehouse

A monthly snow accumulation and melt model is used with gridded monthly temperature and precipitation data for the Northern Hemisphere to generate time series of March snow-covered area (SCA) for the period 1905 through 2002. The time series of estimated SCA for March is verified by comparison with previously published time series of SCA for the Northern Hemisphere. The time series of estimated Northern Hemisphere March SCA shows a substantial decrease since about 1970, and this decrease corresponds to an increase in mean winter Northern Hemisphere temperature. The increase in winter temperature has caused a decrease in the fraction of precipitation that occurs as snow and an increase in snowmelt for some parts of the Northern Hemisphere, particularly the mid-latitudes, thus reducing snow packs and March SCA. In addition, the increase in winter temperature and the decreases in SCA appear to be associated with a contraction of the circumpolar vortex and a poleward movement of storm tracks, resulting in decreased precipitation (and snow) in the low- to mid-latitudes and an increase in precipitation (and snow) in high latitudes. If Northern Hemisphere winter temperatures continue to warm as they have since the 1970s, then March SCA will likely continue to decrease.

Gregory J Mccabe;David M Wolock

2010-01-01

391

Seasonal habitat selection by lake trout (Salvelinus namaycush) in a small Canadian shield lake: Constraints imposed by winter conditions  

USGS Publications Warehouse

The need for cold, well-oxygenated waters significantly reduces the habitat available for lake trout (Salvelinus namaycush) during stratification of small temperate lakes. We examined the spatial and pelagic distribution of lake trout over two consecutive summers and winters and tested whether winter increased habitat availability and access to littoral regions in a boreal shield lake in which pelagic prey fish are absent. In winter, lake trout had a narrowly defined pelagic distribution that was skewed to the upper 3 m of the water column and spatially situated in the central region of the lake. Individual core areas of use (50% Kernel utilization distributions) in winter were much reduced (75%) and spatially non-overlapping compared to summer areas, but activity levels were similar between seasons. Winter habitat selection is in contrast to observations from the stratified season, when lake trout were consistently located in much deeper waters (>6 m) and widely distributed throughout the lake. Winter distribution of lake trout appeared to be strongly influenced by ambient light levels; snow depth and day length accounted for up to 69% of the variation in daily median fish depth. More restricted habitat use during winter than summer was in contrast to our original prediction and illustrates that a different suite of factors influence lake trout distribution between these seasons. ?? Springer Science+Business Media B.V. 2009.

Blanchfield, P. J.; Tate, L. S.; Plumb, J. M.; Acolas, M. -L.; Beaty, K. G.

2009-01-01

392

The Effects of Winter Recreation on Alpine and Subalpine Fauna: A Systematic Review and Meta-Analysis  

PubMed Central

The ski industry is often perceived as having a negative impact on sensitive alpine and subalpine communities. However, empirical evidence of such impacts is lacking. We reviewed the available literature from the last 35 years to quantify the reported effects of winter recreation on faunal communities. Overall, using one-sample binomial tests (‘sign tests’) we found that the effects of all types of winter recreation-related disturbances (i.e. ski runs, resort infrastructure and winter tourism) were more likely to be negative or have no effect, than be positive for wildlife. More specifically, in Europe, where the majority of the available research was conducted, the impacts of winter recreation were most often negative for fauna. In terms of specific taxa, birds and to a lesser extent mammals and arthropods, responded negatively to disturbance. Results from our meta-analysis confirmed the results from our binomial tests. Richness, abundance and diversity of fauna were lower in areas affected by winter recreation when compared with undisturbed areas. For most regions and taxa, however, empirical evidence remains too limited to identify clear impacts of winter recreation. We therefore conclude that the majority of ski resorts are operating in the absence of knowledge needed to inform effective strategies for biodiversity conservation and ecologically-sound management. Thus, there is an urgent need for more empirical research to be conducted throughout this increasingly threatened ecological community, especially given the indication from the available literature that fauna often respond negatively to winter recreation.

Sato, Chloe F.; Wood, Jeff T.; Lindenmayer, David B.

2013-01-01

393

Habitat selection, reproduction and predation of wintering lemmings in the Arctic.  

PubMed

Snow cover has dramatic effects on the structure and functioning of Arctic ecosystems in winter. In the tundra, the subnivean space is the primary habitat of wintering small mammals and may be critical for their survival and reproduction. We have investigated the effects of snow cover and habitat features on the distributions of collared lemming (Dicrostonyx groenlandicus) and brown lemming (Lemmus trimucronatus) winter nests, as well as on their probabilities of reproduction and predation by stoats (Mustela erminea) and arctic foxes (Vulpes lagopus). We sampled 193 lemming winter nests and measured habitat features at all of these nests and at random sites at two spatial scales. We also monitored overwinter ground temperature at a subsample of nest and random sites. Our results demonstrate that nests were primarily located in areas with high micro-topography heterogeneity, steep slopes, deep snow cover providing thermal protection (reduced daily temperature fluctuations) and a high abundance of mosses. The probability of reproduction increased in collared lemming nests at low elevation and in brown lemming nests with high availability of some graminoid species. The probability of predation by stoats was density dependent and was higher in nests used by collared lemmings. Snow cover did not affect the probability of predation of lemming nests by stoats, but deep snow cover limited predation attempts by arctic foxes. We conclude that snow cover plays a key role in the spatial structure of wintering lemming populations and potentially in their population dynamics in the Arctic. PMID:21701915

Duchesne, David; Gauthier, Gilles; Berteaux, Dominique

2011-06-24

394

The early twentieth century warming and winter Arctic sea ice  

NASA Astrophysics Data System (ADS)

The Arctic featured the strongest surface warming over the globe during the recent decades, and the temperature increase was accompanied by a rapid decline in sea ice extent. However, little is known about Arctic sea ice change during the Early Twentieth Century Warming (ETCW) during 1920-1940, also a period of a strong surface warming, both globally and in the Arctic. Here, we investigate the sensitivity of Arctic winter surface air temperature (SAT) to sea ice during 1875-2008 by means of simulations with an atmospheric general circulation model (AGCM) forced by estimates of the observed sea surface temperature (SST) and sea ice concentration. The Arctic warming trend since the 1960s is very well reproduced by the model. In contrast, ETCW in the Arctic is hardly captured. This is consistent with the fact that the sea ice extent in the forcing data does not strongly vary during ETCW. AGCM simulations with observed SST but fixed sea ice reveal a strong dependence of winter SAT on sea ice extent. In particular, the warming during the recent decades is strongly underestimated by the model, if the sea ice extent does not decline and varies only seasonally. This suggests that a significant reduction of Arctic sea ice extent may have also accompanied the Early Twentieth Century Warming, pointing toward an important link between anomalous sea ice extent and Arctic surface temperature variability.

Semenov, V. A.; Latif, M.

2012-06-01

395

Effects of dirty snow in nuclear winter simulations  

SciTech Connect

A large-scale nuclear war would inject smoke into the atmosphere from burning forests, cities, and industries in targeted areas. This smoke could fall out onto snow and ice and would lower cryospheric albedos by as much as 50%. A global energy balance climate model is used to investigate the maximum effect these ''dirty snow'' albedos have on the surface temperature in nuclear winter simulations which span several years. These effects are investigated for different nuclear winter scenarios, snow precipitation rates, latitudinal distributions of smoke, and seasonal timings. We find that dirty snow, in general, would have a small temperature effect at mid- and low latitudes but could have a large temperature effect at polar latitudes, particularly if the soot is able to reappear significantly in later summers. Factors which limit the climatic importance of the dirty snow are (1) the dirty snow albedo is lowest when the atmosphere still contains a large amount of light-absorbing smoke; (2) even with dirty snow, sea ice areas can still increase, which helps maintain colder temperatures through the sea ice thermal inertial feedback; (3) the snow and ice areas affected by the dirty snow albedos are largest when there is little seasonal solar insolation; and (4) the area affected by the dirty snow is relatively small under all circumstances. copyright American Geophysical Union 1988

Vogelmann, A.M.; Robock, A.; Ellingson, R.G.

1988-05-20

396

76 FR 46251 - Endangered and Threatened Wildlife and Plants; 12-Month Finding on a Petition To List the Redrock...  

Federal Register 2010, 2011, 2012, 2013

...replace snowfall. Snowfall is more conducive to groundwater recharge because water from melting snow has a longer time...would be expected to decline later in the summer if groundwater recharge is decreased during future warmer winters...

2011-08-02

397

An analysis of long-term winter data on phytoplankton and zooplankton in Neusiedler See, a shallow temperate lake, Austria  

Microsoft Academic Search

In the last 40 years, the shallow steppe lake, Neusiedler See, was ice covered between 0 and 97 days. The North Atlantic Oscillation\\u000a (NAO) as well as the Mediterranean Oscillation affected the lake and its conditions during winter. Both climate indices correlated\\u000a negatively with the duration of ice cover and the timing of ice-out. Average winter phytoplankton biomass increased from less\\u000a than

Martin T. Dokulil; Alois Herzig

2009-01-01

398

Peripheral Bone Mass is Not Affected by Winter Vitamin D Deficiency in Children and Young Adults from Ushuaia  

Microsoft Academic Search

.   Low vitamin D levels in elderly people are associated with reduced bone mass, secondary hyperparathyroidism, and increased\\u000a fracture risk. Its effect on the growing skeleton is not well known. The aim of this study was to evaluate the possible influence\\u000a of chronic winter vitamin D deficiency and higher winter parathyroid hormone (PTH) levels on bone mass in prepubertal children

M. B. Oliveri; A. Wittich; C. Mautalen; A. Chaperon; A. Kizlansky

2000-01-01

399

Commitment and Compassion: Boston's Comprehensive Policy for the Homeless. Winter Report, December 1989.  

ERIC Educational Resources Information Center

|The people of Boston made a commitment that no homeless person will be denied a bed, a meal, quality health care, and transportation to shelter during the winter of 1989-90. This commitment was difficult to fulfill due to a decline in services for the mentally ill, federal housing cutbacks, and an increase in the number of families living in…

Emergency Shelter Commission, Boston, MA.

400

Carbon fluxes in the rhizosphere of winter wheat and spring barley with conventional vs integrated farming  

Microsoft Academic Search

Estimates of rhizosphere C budgets for winter wheat and spring barley under conventional (CONV) or integrated (INT) management were obtained using a combination of crop growth measurements, 14C pulse-labelling and a model rhizodeposition technique. In both crops the proportion of 14C allocated to shoots 3 wk after labelling increased with the developmental stage, which resulted in maximum belowground C fluxes

J. Swinnen; J. A. Van Veen; R. Merckx

1995-01-01

401

Effects of weather on daily body mass regulation in wintering dunlin  

Microsoft Academic Search

We investigated the influence of changes in weather associated with winter storms on mass balance, activity and food consumption in captive dunlin (Calidris alpina) held in outdoor aviaries, and compared the aviary results with weather-related body mass differences in free-living dunlin collected at Bolinas Lagoon, California. Captive birds fed ad libitum increased their body mass at higher wind speeds and

John P. Kelly; Nils Warnock; Gary W. Page; Wesley W. Weathers

402

Winter Habitat Selection of Mule Deer Before and During Development of a Natural Gas Field  

Microsoft Academic Search

Increased levels of natural gas exploration, development, and production across the Intermountain West have created a variety of concerns for mule deer (Odocoileus hemionus) populations, including direct habitat loss to road and well-pad construction and indirect habitat losses that may occur if deer use declines near roads or well pads. We examined winter habitat selection patterns of adult female mule

HALL SAWYER; RYAN M. NIELSON; FRED LINDZEY; LYMAN L. McDONALD

2006-01-01

403

The winter anomally in ionospheric absorption and the D-region ion chemistry  

Microsoft Academic Search

Interactive mesosphere-D-region processes occurring during a winter day of high ionospheric absorption were investigated. Two NO (+) loss regimes were identified; a temperature profile indicating a strong inversion above 76 km altitude was obtained from the ion composition data. A thermal mesosphere-D-region interaction, in addition to increases in the production of NO (+) and O2 (+), seems required to explain

M. A. Hidalgo

1977-01-01

404

Interaction between Macroinvertebrate Abundance and Habitat Use by Diving Ducks during Winter on Northeastern Lake Ontario  

Microsoft Academic Search

Although numbers of buffleheads (Bucephala albeola), common goldeneyes (Bucephala clangula) and long-tailed ducks (Clangula hyemalis) over-wintering on Lake Ontario have increased substantially over the past two decades, factors influencing habitat use and the potential for competition have not been investigated. The purpose of this study was to determine the relationship between prey availability and community structure of diving ducks during

Michael L. Schummer; Scott A. Petrie; Robert C. Bailey

2008-01-01

405

Spectral Reflectance Properties of Winter Cover Crops in the Southeastern Coastal Plain  

Microsoft Academic Search

Conservation tillage is a commonly adopted best management prac­ tice for reducing runoff and erosion, and increasing infiltration. Yet current methodologies in place to monitor conservation tillage adop­ tion are largely inappropriate for regional or national assessments. A major goal of this study was to evaluate the spectral response proper­ ties of four alternative winter cover crops using remotely derived

D. G. Sullivan; J. N. Shaw; A. Price; E. van Santen

2007-01-01

406

CONTROLLING CHEATGRASS IN WINTER RANGE TO RESTORE HABITAT AND ENDEMIC FIRE  

Microsoft Academic Search

Cheatgrass (Bromus spp.), an introduced, invasive, annual grass of the Western rangelands, increases both fire frequency and intensity, competes with native species for water, space and nutrients, and is a primary cause for loss of habitat quality on elk and deer winter ranges. Studies indicate that rangeland with a 5% cheatgrass composition can become dominated by cheatgrass after a fire.

JOSEPH G. VOLLMER; JENNIFER L. VOLLMER; RYAN AMUNDSON

407

Biology of Young Winter Flounder 'Pseudopleuronectes americanus' (Walbaum); Metabolism Under Simulated Estuarine Conditions.  

National Technical Information Service (NTIS)

Metabolism based on laboratory studies of young winter flounder acclimated to estuarine like conditions show that rates of oxygen uptake (ml O2/hr/g), as a function in increasing temperature, do not differ significantly between salinities of 10 and 20 par...

D. W. Frame

1973-01-01

408

Potential bioethanol and biogas production using lignocellulosic biomass from winter rye, oilseed rape and faba bean  

Microsoft Academic Search

To meet the increasing need for bioenergy several raw materials have to be considered for the production of e.g. bioethanol and biogas. In this study, three lignocellulosic raw materials were studied, i.e. (1) winter rye straw (Secale cereale L), (2) oilseed rape straw (Brassica napus L.) and (3) faba bean straw (Viciafaba L.). Their composition with regard to cellulose, hemicellulose,

Anneli Petersson; Mette H. Thomsen; Henrik Hauggaard-Nielsen; Anne-Belinda Thomsen

2007-01-01

409

Impact of outdoor winter sports on the abundance of a key indicator species of alpine ecosystems  

Microsoft Academic Search

Summary 1. Tourism and leisure activities have increased continuously all over the world during the past decades, exerting a growing pressure upon naturally fragile ecosystems, such as mountainous habitats. Recent studies have established that disturbance by outdoor winter sports (e.g. skiing, snowboarding and snowshoeing) is a source of stress for wildlife. This may in turn affect its abundance, but we

Patrick Patthey; Sven Wirthner; Natalina Signorell; Raphaël Arlettaz

2008-01-01

410

Winter Storms over the San Juan Mountains. Part I: Dynamical Processes  

Microsoft Academic Search

The Colorado River Basin Pilot Project was conducted over the San Juan Mountains in southwestern Colorado and ran for five winter seasons, terminating in 1974-75. The objective of the project was to demonstrate the feasibility of increasing the amount of snowpack and, therefore, the amount of available runoff. The Bureau of Reclamation, through its contractors, conducted the project. A number

John D. Marwitz

1980-01-01

411

The importance of freshwater flows over estuarine mudflats for wintering waders and wildfowl  

Microsoft Academic Search

The attraction of wintering waterbirds to freshwater flowing over intertidal mudflats of estuaries was studied between 1996 and 1998. This was a response to the increasing levels of freshwater abstraction around internationally protected estuaries in the UK, as its relevance to waterbirds was largely undocumented. The numbers and densities of waterbirds in corridors around freshwater flows were consistently greater than

N. O. M Ravenscroft; C. H Beardall

2003-01-01

412

Trends In Wintertime Climate Variability In The Northeastern United States: 1970- 2004  

NASA Astrophysics Data System (ADS)

Humans experience climate variability and climate change primarily through changes in weather at a local and regional scale. One of the most effective means to track these changes is through detailed analysis of meteorological data. In this work, changes in the winter climate of the northeastern United States are documented. Snow on the ground and snowfall are important components in water management, travel safety, and winter tourism and recreation. Trends in Temperature, snowfall, and snow depth data were collected from the United States Historical Climate Network (USHCN). The months of December through March are selected for winter climate analysis. Monthly and seasonal time series of the number of days with snow on the ground greater than 1, 3, and 5 inches are constructed from snow depth data. The National Climatic Data Center and Carbon Dioxide Information Analysis Center perform extensive quality assurance and quality control measures for monthly temperature data. However, daily snowfall and snow depth data have not been adjusted for station relocations, instrument changes, or time of observation biases. To address these data quality issues, we evaluate daily data for spatial coherence with nearest neighbors, and remove stations with non-climatic influences from regional analysis. Monthly and seasonal trends in mean, minimum and maximum temperature, total snowfall, and days with snow on the ground are estimated using linear regression and robust spline analysis. Northeastern United States winter temperatures are warming at a rate significantly greater than the global average. At stations located north of 44oN, December snowfall exhibits a decreasing trend (-3.5 inches/decade), whereas March snowfall is increasing (+1.3 inches/decade) over the period 1970-2004. Across the northeastern United States, the number of days with snow on the ground has also decreased substantially. The results hold important implications for the winter economy and recreation in the region.

Burakowski, E. A.; Wake, C. P.; Braswell, B.

2007-12-01

413

Global climate change and reindeer: effects of winter weather on the autumn weight and growth of calves.  

PubMed

Reindeer/caribou (Rangifer tarandus), which constitute a biological resource of vital importance for the physical and cultural survival of Arctic residents, and inhabit extremely seasonal environments, have received little attention in the global change debate. We investigated how body weight and growth rate of reindeer calves were affected by large-scale climatic variability [measured by the North Atlantic Oscillation (NAO) winter index] and density in one population in central Norway. Body weights of calves in summer and early winter, as well as their growth rate (summer to early winter), were significantly influenced by density and the NAO index when cohorts were in utero. Males were heavier and had higher absolute growth than females, but there was no evidence that preweaning condition of male and female calves were influenced differently by the NAO winter index. Increasing NAO index had a negative effect on calves' body weight and growth rate. Increasing density significantly reduced body weight and growth rate of calves, and accentuated the effect of the NAO winter index. Winters with a higher NAO index are thus severe for reindeer calves in this area and their effects are associated with nutritional stress experienced by the dams during pregnancy or immediately after calving. Moreover, increased density may enhance intra-specific competition and limits food available at the individual level within cohorts. We conclude that if the current pattern of global warming continues, with greater change occurring in northern latitudes and during winter as is predicted, reduced body weight of reindeer calves may be a consequence in areas where winters with a high NAO index are severe. This will likely have an effect on the livelihood of many northern indigenous peoples, both economically and culturally. PMID:12707839

Weladji, Robert B; Holand, Øystein

2003-04-18

414

Factors affecting outdoor exposure in winter: population-based study.  

PubMed

The extent of outdoor exposure during winter and factors affecting it were examined in a cross-sectional population study in Finland. Men and women aged 25-74 years from the National FINRISK 2002 sub-study (n=6,591) were queried about their average weekly occupational, leisure-time and total cold exposure during the past winter. The effects of gender, age, area of residence, occupation, ambient temperature, self-rated health, physical activity and education on cold exposure were analysed. The self-reported median total cold exposure time was 7 h/week (8 h men, 6 h women),<1 h/week (2 h men, 0 h women) at work, 4 h/week (5 h men, 4 h women) during leisure time and 1 h/week (1 h men, 1.5 h women) while commuting to work. Factors associated with increased occupational cold exposure among men were: being employed in agriculture, forestry and industry/mining/construction or related occupations, being less educated and being aged 55-64 years. Factors associated with increased leisure-time cold exposure among men were: employment in industry/mining/construction or related occupations, being a pensioner or unemployed, reporting at least average health, being physically active and having college or vocational education. Among women, being a housewife, pensioner or unemployed and engaged in physical activity increased leisure-time cold exposure, and young women were more exposed than older ones. Self-rated health was positively associated with leisure time cold exposure in men and only to a minor extent in women. In conclusion, the subjects reported spending 4% of their total time under cold exposure, most of it (71%) during leisure time. Both occupational and leisure-time cold exposure is greater among men than women. PMID:16788837

Mäkinen, Tiina M; Raatikka, Veli-Pekka; Rytkönen, Mika; Jokelainen, Jari; Rintamäki, Hannu; Ruuhela, Reija; Näyhä, Simo; Hassi, Juhani

2006-06-21

415

Grass pea as a nitrogen source for no-till winter wheat and tilled winter wheat  

Technology Transfer Automated Retrieval System (TEKTRAN)

We examined how grass pea (GP), a cool-season pulse, might function as a pre-plant N source for continuous, no-till winter wheat. We planted grass pea into 3 experimental plots during mid-August 2005 through 2008 and allowed it to grow until mid-October when the plots were shredded, sprayed with he...

416

Atmospheric Climatology and Its Effect on Sea Surface Temperature-Winter 1977 to Winter 1978.  

National Technical Information Service (NTIS)

Figures summarize the anomalous tendencies of atmosphere and ocean for the year 1977 as a whole. As expected the mean annual distribution of 700 bm height anomaly is mainly a reflection of the extreme developments of the winter season, with its polar ridg...

R. R. Dickson J. Namias

1979-01-01

417

Winter Extremes Temperature on the Iberian Peninsula  

NASA Astrophysics Data System (ADS)

Extreme temperatures in winter for the period from 1948 to 2008 on The Iberian Peninsula have been analyzed in order to study the connection between temperatures and the large scale atmospheric circulation. The analysis was made using the same method used by Yiou et al. (2007). However, we center our study on the Iberian Peninsula using a daily maximum and minimum temperature data from the Agencia Estatal de Meteorologia's (AEMET) 45 different stations distributed around the Peninsula. In order to characterize the North-Atlantic atmospheric flow we used the geopotential height at 500 mb from the National Centers for Environmental Prediction (NCEP) reanalysis for the 1948-2008 period, over the (80W; 50E; 25N; 70N) area. The connection between the large scale flow and extreme temperatures, is investigated by statistically reconstructing the temperature starting from of analogues of the circulation. External forcings that can also contribute to the development of temperature extremes are also analysed. References P. Yiou, R. Vautard, P. Naveau, and C. Cassou, 2007, Inconsistency between atmospheric dynamics and temperatures during the exceptional 2006/2007 fall/winter and recent warming in Europe, Geophysical Research Letters, Vol. 34, L21808, doi:10.1029/2007GL031981.

Aizpurua, P.; D'Andrea, F.; García-Herrera, R.

2009-04-01

418

Gravity wave activity during winter above Esrange  

NASA Astrophysics Data System (ADS)

This study of mountain wave propagation over northern Sweden makes use of data from radiosondes, launched at Esrange (67.6°N, 21.0°E), and from the ESRAD, the Esrange VHF Doppler radar, which have been recorded during winter 1996/97 to 2000/01. As the predominant low-level wind direction with high wind speeds above Esrange is from the north-west, and the upper tropospheric winds are most frequently westerly, one might expect critical level filtering to be relatively unimportant in this region. Despite this, it turned out that radar data as well as the radiosonde data show clear evidence of inhibited wave activity due to critical level filtering. Enhanced wave activity is found mainly in cases where no critical level filtering has occurred. Further, an indication for lower temperatures in the stratosphere during enhanced wave activity has been seen. The observed inter-annual variation in wave activity can be explained by differences in the wave generation due to differences in the mean wind speeds during the winters. The ratio of wave activity in the upper troposphere compared to the wave activity in the lower troposphere is clearly influenced by the amount of critical level filtering.

Stebel, K.; Hooper, D. A.; Kirkwood, S.

2001-08-01

419

Personality disorders in patients with winter depression.  

PubMed

Sixty-six patients satisfying the criteria for seasonal affective disorder (SAD) winter depression type (n = 57) or subsyndromal SAD (n = 9), were interviewed in a nondepressed state with the Structured Interview for DSM-III-R Personality Disorders (SIDP-R). Twenty-three percent of the patients in the SAD sample met DSM-III-R criteria for one or more categorical diagnosis of personality disorder (PD). Disorders in cluster C occurred in 18% of the sample, while 12% had cluster B PDs and 5% a cluster A disorder. The relative number of positive criteria, as a dimensional measure of PD, were higher for all cluster C disorders than for any PD in the other clusters. Our data indicate that the pattern of personality disorders in patients with winter SAD are similar to that previously reported for outpatients with non-SAD major depression. We explored the relationship between lifetime severity and clinical manifestation of SAD and dimensional measures of PD with multiple regression analyses. No significant association was found. This is in accordance with the hypothesis that the two disorders are distinct conditions with independent causes. PMID:7892772

Reichborn-Kjennerud, T; Lingjaerde, O; Dahl, A A

1994-12-01

420

Aspen Winter Conferences on High Energy  

SciTech Connect

The 2011 Aspen Winter Conference on Particle Physics was held at the Aspen Center for Physics from February 12 to February 18, 2011. Ninety-four participants from ten countries, and several universities and national labs attended the workshop titled, ?New Data From the Energy Frontier.? There were 54 formal talks, and a considerable number of informal discussions held during the week. The week?s events included a public lecture (?The Hunt for the Elusive Higgs Boson? given by Ben Kilminster from Ohio State University) and attended by 119 members of the public, and a physics caf? geared for high schoolers that is a discussion with physicists. The 2011 Aspen Winter Conference on Astroparticle physics held at the Aspen Center for Physics was ?Indirect and Direct Detection of Dark Matter.? It was held from February 6 to February 12, 2011. The 70 participants came from 7 countries and attended 53 talks over five days. Late mornings through the afternoon are reserved for informal discussions. In feedback received from participants, it is often these unplanned chats that produce the most excitement due to working through problems with fellow physicists from other institutions and countries or due to incipient collaborations. In addition, Blas Cabrera of Stanford University gave a public lecture titled ?What Makes Up Dark Matter.? There were 183 members of the general public in attendance. Before the lecture, 45 people attended the physics caf? to discuss dark matter. This report provides the attendee lists, programs, and announcement posters for each event.

multiple speakers, presenters listed on link below

2011-02-12

421

Echo Meadows Project Winter Artificial Recharge.  

SciTech Connect

This report discusses the findings of the Echo Meadows Project (BPA Project 2001-015-00). The main purpose of this project is to artificially recharge an alluvial aquifer, WITH water from Umatilla River during the winter high flow period. In turn, this recharged aquifer will discharge an increased flow of cool groundwater back to the river, thereby improving Umatilla River water quality and temperature. A considerable side benefit is that the Umatilla River should improve as a habitat for migration, spanning, and rearing of anadromous and resident fish. The scope of this project is to provide critical baseline information about the Echo Meadows and the associated reach of the Umatilla River. Key elements of information that has been gathered include: (1) Annual and seasonal groundwater levels in the aquifer with an emphasis on the irrigation season, (2) Groundwater hydraulic properties, particularly hydraulic conductivity and specific yield, and (3) Groundwater and Umatilla River water quality including temperature, nutrients and other indicator parameters. One of the major purposes of this data gathering was to develop input to a groundwater model of the area. The purpose of the model is to estimate our ability to recharge this aquifer using water that is only available outside of the irrigation season (December through the end of February) and to estimate the timing of groundwater return flow back to the river. We have found through the data collection and modeling efforts that this reach of the river had historically returned as much as 45 cubic feet per second (cfs) of water to the Umatilla River during the summer and early fall. However, this return flow was reduced to as low as 10 cfs primarily due to reduced quantities of irrigation application, gain in irrigation efficiencies and increased groundwater pumping. Our modeling indicated that it is possible to restore these critical return flows using applied water outside of the irrigation season. We further found that this water can be timed to return to the river during the desired time of the year (summer to early fall). This is because the river stage, which remains relatively high until this time, drops during the irrigation season-thereby releasing the stored groundwater and increasing river flows. A significant side benefit is that these enhanced groundwater return flows will be clean and cold, particularly as compared to the Umatilla River. We also believe that this same type of application of water could be done and the resulting stream flows could be realized in other watersheds throughout the Pacific Northwest. This means that it is critical to compare the results from this baseline report to the full implementation of the project in the next phase. As previously stated, this report only discusses the results of data gathered during the baseline phase of this project. We have attempted to make the data that has been gathered accessible with the enclosed databases and spreadsheets. We provide computer links in this report to the databases so that interested parties can fully evaluate the data that has been gathered. However, we cannot emphasize too strongly that the real value of this project is to implement the phases to come, compare the results of these future phases to this baseline and develop the science and strategies to successfully implement this concept to other rivers in the Pacific Northwest. The results from our verified and calibrated groundwater model matches the observed groundwater data and trends collected during the baseline phase. The modeling results indicate that the return flows may increase to their historic values with the addition of 1 acre-ft/acre of recharge water to the groundwater system (about 9,600 acre-feet total). What this means is that through continued recharge project, you can double to quadruple the annual baseflow of the Umatilla River during the low summer and fall flow periods as compared to the present base-flow. The cool and high quality recharge water is a significant beneficial impact to the river system.

Ziari, Fred

2002-12-19

422

A comparative study of the major sudden stratospheric warmings in the Arctic winters 2003/2004-2009/2010  

NASA Astrophysics Data System (ADS)

We present an analysis of the major sudden stratospheric warmings (SSWs) in the Arctic winters 2003/04-2009/10. There were 6 major SSWs (major warmings [MWs]) in 6 out of the 7 winters, in which the MWs of 2003/04, 2005/06, and 2008/09 were in January and those of 2006/07, 2007/08, and 2009/10 were in February. Although the winter 2009/10 was relatively cold from mid-December to mid-January, strong wave 1 activity led to a MW in early February, for which the largest momentum flux among the winters was estimated at 60° N/10 hPa, about 450 m2 s-2. The strongest MW, however, was observed in 2008/09 and the weakest in 2006/07. The MW in 2008/09 was triggered by intense wave 2 activity and was a vortex split event. In contrast, strong wave 1 activity led to the MWs of other winters and were vortex displacement events. Large amounts of Eliassen-Palm (EP) and wave 1/2 EP fluxes (about 2-4 ×105 kg s-2) are estimated shortly before the MWs at 100 hPa averaged over 45-75° N in all winters, suggesting profound tropospheric forcing for the MWs. We observe an increase in the occurrence of MWs (~1.1 MWs/winter) in recent years (1998/99-2009/10), as there were 13 MWs in the 12 Arctic winters, although the long-term average (1957/58-2009/10) of the frequency stays around its historical value (~0.7 MWs/winter), consistent with the findings of previous studies. An analysis of the chemical ozone loss in the past 17 Arctic winters (1993/94-2009/10) suggests that the loss is inversely proportional to the intensity and timing of MWs in each winter, where early (December-January) MWs lead to minimal ozone loss. Therefore, this high frequency of MWs in recent Arctic winters has significant implications for stratospheric ozone trends in the northern hemisphere.

Kuttippurath, J.; Nikulin, G.

2012-09-01

423

The 'Winter' Analogy Fallacy: From superbombs to supervolcanoes  

Microsoft Academic Search

In the late 1980s, a few volcanologists created an ill-founded analogy. Drawing upon the then-fashionable 'nuclear winter' theory, they claimed that certain explosive eruptions in historic times might have led to 'volcanic winters.' The nuclear winter debate of the 1980s was about the possibly disastrous effects of a nuclear war on the Earth's atmosphere and climate, thus on agriculture, and

Matthias Dörries

424

Changes in winter precipitation extremes for the western United States under a warmer climate as simulated by regional climate models  

NASA Astrophysics Data System (ADS)

We find a consistent and statistically significant increase in the intensity of future extreme winter precipitation events over the western United States, as simulated by an ensemble of regional climate models (RCMs) driven by IPCC AR4 global climate models (GCMs). All eight simulations analyzed in this work consistently show an increase in the intensity of extreme winter precipitation with the multi-model mean projecting an area-averaged 12.6% increase in 20-year return period and 14.4% increase in 50-year return period daily precipitation. In contrast with extreme precipitation, the multi-model ensemble shows a decrease in mean winter precipitation of approximately 7.5% in the southwestern US, while the interior west shows less statistically robust increases.

Dominguez, F.; Rivera, E.; Lettenmaier, D. P.; Castro, C. L.

2012-03-01

425

The Indian Ocean Atmosphere During Boreal Winter: A "melting Pot"  

NASA Astrophysics Data System (ADS)

In recent years our knowledge about the Indian Ocean region during the winter mon- soon period has increased considerably, largely due to the INDOEX campaigns. First results and analyses show a variety of processes occuring that are important for the chemical composition of the Indian Ocean atmosphere. They also make analyses more difficult because it is often hard to distinguish between the different processes, giving the impression of this region being a "melting pot" of different airmasses from differ- ent source regions around the globe. In this presentation I will try to summarize the important processes in the Indian Ocean atmosphere, their main mechanisms, their effects on the chemical composition and their temporal and spatial variability.

de Laat, A. T. J.

426

Biogeochemical plant site conditions in stream valleys after winter flooding: a phytometer approach  

NASA Astrophysics Data System (ADS)

Reintroduction of winter flooding events will have strong effects on the plant growth conditions in the parts of stream valleys that have not been accustomed to flooding in recent years. The major goal of this research is, firstly, to investigate the plant growth conditions in floodplain soils in the period after a winter flood and, secondly, to assess whether a phytometer setup is suitable for the evaluation of winter flooding on plant growth conditions. Soil cores of three agricultural and three semi-natural grassland sites have been exposed to a simulated winter flooding event. Then, cores were subjected to spring conditions in a growth chamber and were planted with seedlings of Anthoxantum odoratum and Lythrum salicaria. The growth conditions changed in opposite directions for our two phytometer species, expressed as biomass and nutrient changes. We discuss possible causes of an increase or decrease in biomass, such as (1) soil nutrient effects (N, P and K), (2) toxic effects of NH4, Fe and Al, and (3) possible shortage of other macro- and micronutrients. The conclusions are that plant growth after winter flooding was affected by enhanced nutrient and toxicant availabilities in agricultural sites and mainly by soil nutrients in the semi-natural sites. The use of the two species selected had clear advantages: Lythrum salicaria is well-suited to assess the nutrient status in previously flooded soils, because it is a well-known invader of wetlands and not easily hampered by potentially toxic compounds, while A. odoratum is less frequently found at wetland soils and more sensitive to toxic compounds and, therefore, a better indicator of possible toxic effects as a result of winter flooding than L. salicaria.

Beumer, V.; Ohm, J. N.; van Wirdum, G.; Beltman, B.; Griffioen, J.; Verhoeven, J. T. A.

2008-12-01

427

On interannual variations of the winter temperature at Faraday/Vernadsky Antarctic Station  

NASA Astrophysics Data System (ADS)

The interannual variations of the winter temperature at Faraday/Vernadsky Station, West Antarctic Peninsula are investigated. The meteorological READER surface air temperature and wind velocity/direction data for 1947-2007 period as well as the temperature and zonal/meridional wind distribution at 1000 hPa from the NCEP-NCAR reanalysis data (1979-2007) were used. The possible reasons of observed winter warming are discussed. The winter warming is accompanied by narrowing of the temperature variation range between -14°C and -4°C during 1950s to -8°C and -4°C in last decade. Positive trend in annual mean and winter mean temperature corresponds to lowering of the "depth" of cold winter anomalies, which can relate to the area located to the east of Antarctic Peninsula. The indications are seen from agreement between the interannual variations in winter temperature at Faraday/Vernadsky and the east-west migrations of quasistationary distribution of surface air temperature and zonal/meridional wind in Antarctic Peninsula region. The meteorological observations at Faraday/Vernadsky station display long-term changes in the wind distribution pattern: the appearance frequency of the "continental" wind (0°E±45° azimuth) observation has been reduced but the appearance frequency of the "ocean" wind (180°E±45° azimuth) has been increased threefold in the last two decades in comparison to 1950s-1970s. That is evidence of the structural change-over of circulation pattern in the region which is advantageous for warming. Results show that the changes in the quasistationary pattern in Antarctic troposphere contribute to the local climate change in Antarctic Peninsula region. The research was partly supported by National Taras Shevchenko University of Kyiv, project 06BF051-12.

Evtushevsky, A.; Kravchenko, V.; Grytsai, A.; Milinevsky, G.

2009-04-01

428

Physical properties of normal grade biodiesel and winter grade biodiesel.  

PubMed

In this study, optical and thermal properties of normal grade and winter grade palm oil biodiesel were investigated. Surface Plasmon Resonance and Photopyroelectric technique were used to evaluate the samples. The dispersion curve and thermal diffusivity were obtained. Consequently, the variation of refractive index, as a function of wavelength in normal grade biodiesel is faster than winter grade palm oil biodiesel, and the thermal diffusivity of winter grade biodiesel is higher than the thermal diffusivity of normal grade biodiesel. This is attributed to the higher palmitic acid C(16:0) content in normal grade than in winter grade palm oil biodiesel. PMID:21731429

Sadrolhosseini, Amir Reza; Moksin, Mohd Maarof; Nang, Harrison Lau Lik; Norozi, Monir; Yunus, W Mahmood Mat; Zakaria, Azmi

2011-03-25

429

Elevated Blood Lead Concentrations and Vitamin D Deficiency in Winter and Summer in Young Urban Children  

PubMed Central

Background It is widely recognized that blood lead concentrations are higher in the summer than in winter. Although the effects of some environmental factors such as lead in dust on this phenomenon have been studied, relationships to sunlight-induced vitamin D synthesis have not been adequately investigated. Vitamin D status is influenced by the diet, sunlight exposure, age, skin pigmentation, and other factors, and may modify gastrointestinal lead absorption or release of lead stored in bones into the bloodstream. Objective and Methods We collected paired blood samples from 142 young, urban African-American and Hispanic children in the winter and summer to study the seasonal increase in blood lead and its relationships to vitamin D nutrition, age, and race. Results A winter/summer (W/S) increase in blood lead concentrations of 32.4% was found for children 1–3 years of age. There was a smaller W/S increase of 13.0% in children 4–8 years of age. None of the 51 Hispanic children had an elevated blood lead concentration (? 10 ?g/dL) during the winter, and only one had an elevated summertime concentration. In contrast, elevated blood lead concentrations were frequent in the 91 African-American children, especially those 1–3 years of age. For the latter, the percentage with elevated blood lead levels increased from 12.2% in winter to 22.5% in summer. A 1.2% W/S increase in serum 25-hydroxy-vitamin D (serum 25-OH-D) concentrations was found for children 1–3 years of age. However, in children 4–8 years of age the W/S increase in serum 25-OH-D was much larger—33.6%. The percentages of children with low (< 16 ?g/L) serum 25-OH-D concentrations were 12.0% in winter and 0.7% in summer and were consistently greater in African-American than in Hispanic children. The seasonal increases in blood lead and serum 25-OH-D in children 4–8 years of age were significantly associated. Conclusion The higher summertime serum 25-OH-D concentrations for the 4- to 8-year-old children are likely caused by increased sunlight-induced vitamin D synthesis and may contribute to the seasonal increase in blood lead. Age and race are key factors that affect blood lead and vitamin D nutrition, as well as their interactions, in young urban children.

Kemp, Francis W.; Neti, Prasad V.S.V.; Howell, Roger W.; Wenger, Peter; Louria, Donald B.; Bogden, John D.

2007-01-01

430

Estimating flow rates to optimize winter habitat for centrarchid fish in mississippi river (USA) backwaters  

USGS Publications Warehouse

The backwaters of large rivers provide winter refuge for many riverine fish, but they often exhibit low dissolved oxygen levels due to high biological oxygen demand and low flows. Introducing water from the main channel can increase oxygen levels in backwaters, but can also increase current velocity and reduce temperature during winter, which may reduce habitat suitability for fish. In 1993, culverts were installed to introduce flow to the Finger Lakes, a system of six backwater lakes on the Mississippi River, about 160 km downstream from Minneapolis, Minnesota. The goal was to improve habitat for bluegills and black crappies during winter by providing dissolved oxygen concentrations > 3 mg/L, current velocities < 1 cm/s, and temperatures < 1??C. To achieve these conditions, we used data on lake volume and oxygen demand to estimate the minimum flow required to maintain 3 mg/L of dissolved oxygen in each lake. Estimated flows ranged from 0.02 to 0.14 m3/s among lakes. Data gathered in winter 1994 after the culverts were opened, indicated that the estimated flows met habitat goals, but that thermal stratification and lake morphometry can reduce the volume of optimal habitat created.

Johnson, B. L.; Knights, B. C.; Barko, J. W.; Gaugush, R. F.; Soballe, D. M.; James, W. F.

1998-01-01

431

Metabolic response to lipid infusion in fasting winter-acclimatized king penguin chicks (Aptenodytes patagonicus).  

PubMed

During the cold austral winter, king penguin chicks are infrequently fed by their parents and thus experience severe nutritional deprivation under harsh environmental conditions. These energetic constraints lead to a range of energy sparing mechanisms balanced by the maintenance of efficient thermogenic processes. The present work investigated whether the high thermogenic capacities exhibited by winter-acclimatized king penguin chicks could be related to an increase in lipid substrate supply and oxidation in skeletal muscle, the main site of thermogenesis in birds. To test this hypothesis, we examined i) the effect of an experimental rise in plasma triglyceride on the whole metabolic rate in winter-acclimatized (WA) and de-acclimatized king penguin chicks kept at thermoneutrality (TN), and ii) investigated the fuel preference of muscle mitochondria. In vivo, a perfusion of a lipid emulsion induced a small 10% increase of metabolic rate in WA chicks but not in TN group. In vitro, the oxidation rate of muscle mitochondria respiring on lipid-derived substrate was +40% higher in WA chicks than in TN, while no differences were found between groups when mitochondria oxidized carbohydrate-derived substrate or succinate. Despite an enhanced fuel selection towards lipid oxidation in skeletal muscle, a rise of circulating lipids per se was not sufficient to fully unravel the thermogenic capacity of winter-acclimatized king penguin chicks. PMID:23428720

Teulier, Loïc; Tornos, Jérémy; Rouanet, Jean-Louis; Rey, Benjamin; Roussel, Damien

2013-02-18

432

Winter precipitation change in South China in recent decades  

NASA Astrophysics Data System (ADS)

Precipitation change is one of important climate researches in China, but winter precipitation variation in South China has not been studied so frequently. In China, it is rainy when hot; so summer precipitation is usually one focus in research, esp. in South China. However, winter precipitation and its change influence people profoundly in South China, also. The most recent example is what happened over South China in winter 2008. In this winter, millions of people suffered from the unusual cold and snowy winter. It led to huge loss in economy and traffic as well. Roads closed and railway stations were jammed and crowded with people; many planes were grounded for heavy snow and bad weather. Transmission lines faulted in the mountains. The ommunication signals were affected. Everyday food supply including vegetables and meats had to be delayed or interrupted. In some city even water supply was interrupted. And garbage in the city was piled up. Just in this winter the snow depth and coverage area in many places in South China broke or equaled the historical records. In fact, it isn't the only one unusual winter precipitation event in South China. Since 1950s, several freezing and snowy winters struck the South in China. In this research, winter precipitation change in recent years in South China has been discussed based on the precipitation observations. The associated large scale atmospheric circulation change is also analyzed. It is found that snowy winter in South China hardly comes in most periods of 2000s, but in recent decades this heavy snow in winter has appeared several times as observations shows. This phenomenon could be related to the large scale atmospheric circulation change.

Cai, Jingning

2013-04-01

433

Linking summer foraging to winter survival in yellow pine chipmunks (Tamias amoenus).  

PubMed

This study links summer foraging and scatter-hoarding to winter larder-hoarding and winter survival in yellow pine chipmunks (Tamias amoenus) by comparing patterns of time allocation and winter larder contents in 2 years with very different levels of resource availability. In 2003, seed production and the number of trees and shrubs producing seeds were high. In 2004 seed crops were small. Chipmunks allocated more time to foraging when food resources were scarce (66% in 2004) compared to when they were abundant (39% in 2003). Increased time allocated to foraging in 2004 corresponded to significant decreases in time allocated to vigilance, resting, and social interactions. When seeds were scarce (i.e., in autumn 2004), chipmunks spent more time searching for cached food items than gathering seeds from plants or the ground surface. Despite the increase in foraging effort, the edible mass and caloric contents of larders were significantly smaller in 2004. In the year with low seed production, the diversity of seed species found in larders increased, and many of these seeds were of species that ripened in summer. When autumnal seed production by Jeffrey pine seeds was high, Jeffrey pine seeds were nearly the exclusive food item found in larders. Larder contents would have provisioned chipmunks for an estimated 116-257 days in 2003 and but only 6-111 days in 2004. It is likely that all chipmunks would have survived the winter of 2003 (duration approximately 110-120 days). However, none of the larders recovered in 2004 contained enough food to have provisioned the inhabitant for the approximately148-158 days of winter. PMID:18560900

Kuhn, Kellie M; Vander Wall, Stephen B

2008-06-17