Science.gov

Sample records for dangerous temperature change

  1. Avoiding dangerous climate change

    SciTech Connect

    Hans Joachim Schellnhuber; Wolfgang Cramer; Nebojsa Nakicenovic; Tom Wigley; Gary Yohe

    2006-02-15

    In 2005 the UK Government hosted the Avoiding Dangerous Climate Change conference to take an in-depth look at the scientific issues associated with climate change. This volume presents the most recent findings from the leading international scientists that attended the conference. The topics addressed include critical thresholds and key vulnerabilities of the climate system, impacts on human and natural systems, socioeconomic costs and benefits of emissions pathways, and technological options for meeting different stabilisation levels of greenhouse gases in the atmosphere. Contents are: Foreword from Prime Minister Tony Blair; Introduction from Rajendra Pachauri, Chairman of the IPCC; followed by 41 papers arranged in seven sections entitled: Key Vulnerabilities of the Climate System and Critical Thresholds; General Perspectives on Dangerous Impacts; Key Vulnerabilities for Ecosystems and Biodiversity; Socio-Economic Effects; Regional Perspectives; Emission Pathways; and Technological Options. Four papers have been abstracted separately for the Coal Abstracts database.

  2. Beyond 'dangerous' climate change: emission scenarios for a new world.

    PubMed

    Anderson, Kevin; Bows, Alice

    2011-01-13

    The Copenhagen Accord reiterates the international community's commitment to 'hold the increase in global temperature below 2 degrees Celsius'. Yet its preferred focus on global emission peak dates and longer-term reduction targets, without recourse to cumulative emission budgets, belies seriously the scale and scope of mitigation necessary to meet such a commitment. Moreover, the pivotal importance of emissions from non-Annex 1 nations in shaping available space for Annex 1 emission pathways received, and continues to receive, little attention. Building on previous studies, this paper uses a cumulative emissions framing, broken down to Annex 1 and non-Annex 1 nations, to understand the implications of rapid emission growth in nations such as China and India, for mitigation rates elsewhere. The analysis suggests that despite high-level statements to the contrary, there is now little to no chance of maintaining the global mean surface temperature at or below 2°C. Moreover, the impacts associated with 2°C have been revised upwards, sufficiently so that 2°C now more appropriately represents the threshold between 'dangerous' and 'extremely dangerous' climate change. Ultimately, the science of climate change allied with the emission scenarios for Annex 1 and non-Annex 1 nations suggests a radically different framing of the mitigation and adaptation challenge from that accompanying many other analyses, particularly those directly informing policy. PMID:21115511

  3. Our contaminated atmosphere: The danger of climate change, phases 1 and 2. [effect of atmospheric particulate matter on surface temperature and earth's radiation budget

    NASA Technical Reports Server (NTRS)

    Cimorelli, A. J.; House, F. B.

    1974-01-01

    The effects of increased concentrations of atmospheric particulate matter on average surface temperature and on the components of the earth's radiation budget are studied. An atmospheric model which couples particulate loading to surface temperature and to changes in the earth's radiation budget was used. A determination of the feasibility of using satellites to monitor the effect of increased atmospheric particulate concentrations is performed. It was found that: (1) a change in man-made particulate loading of a factor of 4 is sufficient to initiate an ice age; (2) variations in the global and hemispheric weighted averages of surface temperature, reflected radiant fluz and emitted radiant flux are nonlinear functions of particulate loading; and (3) a black satellite sphere meets the requirement of night time measurement sensitivity, but not the required day time sensitivity. A nonblack, spherical radiometer whose external optical properties are sensitive to either the reflected radiant fluz or the emitted radiant flux meets the observational sensitivity requirements.

  4. Global atmospheric methane: budget, changes and dangers.

    PubMed

    Dlugokencky, Edward J; Nisbet, Euan G; Fisher, Rebecca; Lowry, David

    2011-05-28

    A factor of 2.5 increase in the global abundance of atmospheric methane (CH(4)) since 1750 contributes 0.5 Wm(-2) to total direct radiative forcing by long-lived greenhouse gases (2.77 Wm(-2) in 2009), while its role in atmospheric chemistry adds another approximately 0.2 Wm(-2) of indirect forcing. Since CH(4) has a relatively short lifetime and it is very close to a steady state, reductions in its emissions would quickly benefit climate. Sensible emission mitigation strategies require quantitative understanding of CH(4)'s budget of emissions and sinks. Atmospheric observations of CH(4) abundance and its rate of increase, combined with an estimate of the CH(4) lifetime, constrain total global CH(4) emissions to between 500 and 600 Tg CH(4) yr(-1). While total global emissions are constrained reasonably well, estimates of emissions by source sector vary by up to a factor of 2. Current observation networks are suitable to constrain emissions at large scales (e.g. global) but not at the regional to national scales necessary to verify emission reductions under emissions trading schemes. Improved constraints on the global CH(4) budget and its break down of emissions by source sector and country will come from an enhanced observation network for CH(4) abundance and its isotopic composition (δ(13)C, δD(D=(2)H) and δ(14)C). Isotopic measurements are a valuable tool in distinguishing among various sources that contribute emissions to an air parcel, once fractionation by loss processes is accounted for. Isotopic measurements are especially useful at regional scales where signals are larger. Reducing emissions from many anthropogenic source sectors is cost-effective, but these gains may be cancelled, in part, by increasing emissions related to economic development in many parts of the world. An observation network that can quantitatively assess these changing emissions, both positive and negative, is required, especially in the context of emissions trading schemes. PMID

  5. Communicating the Need to Avoid Dangerous Climate Change (Invited)

    NASA Astrophysics Data System (ADS)

    Hansen, J. E.; Kharecha, P. A.; Sato, M.

    2013-12-01

    We describe our past, ongoing and planned efforts to communicate the need for humanity to avoid dangerous climate change. Communications with governments have been largely fruitless, with substantial indication that governments are more disposed to be responsive to financial interests rather than scientific information. Communication with the public is essential to create pressure on governments for appropriate policies, but it is made difficult by the massive resources of the fossil fuel industry. Communication with influential individuals can be effective in reaching both governments and the public.

  6. The 2003 heat wave in France: dangerous climate change here and now.

    PubMed

    Poumadère, Marc; Mays, Claire; Le Mer, Sophie; Blong, Russell

    2005-12-01

    In an analysis of the French episode of heat wave in 2003, this article highlights how heat wave dangers result from the intricate association of natural and social factors. Unusually high temperatures, as well as socioeconomic vulnerability, along with social attenuation of hazards, in a general context where the anthropogenic contribution to climate change is becoming more plausible, led to an excess of 14,947 deaths in France, between August 4 and 18, 2003. The greatest increase in mortality was due to causes directly attributable to heat: dehydration, hyperthermia, heat stroke. In addition to age and gender, combinatorial factors included preexisting disease, medication, urban residence, isolation, poverty, and, probably, air pollution. Although diversely impacted or reported, many parts of Europe suffered human and other losses, such as farming and forestry through drought and fires. Summer 2003 was the hottest in Europe since 1500, very likely due in part to anthropogenic climate change. The French experience confirms research establishing that heat waves are a major mortal risk, number one among so-called natural hazards in postindustrial societies. Yet France had no policy in place, as if dangerous climate were restricted to a distant or uncertain future of climate change, or to preindustrial countries. We analyze the heat wave's profile as a strongly attenuated risk in the French context, as well as the causes and the effects of its sudden shift into amplification. Research and preparedness needs are highlighted. PMID:16506977

  7. Climate-society feedbacks and the avoidance of dangerous climate change

    NASA Astrophysics Data System (ADS)

    Jarvis, A. J.; Leedal, D. T.; Hewitt, C. N.

    2012-09-01

    The growth in anthropogenic CO2 emissions experienced since the onset of the Industrial Revolution is the most important disturbance operating on the Earth's climate system. To avoid dangerous climate change, future greenhouse-gas emissions will have to deviate from business-as-usual trajectories. This implies that feedback links need to exist between climate change and societal actions. Here, we show that, consciously or otherwise, these feedbacks can be represented by linking global mean temperature change to the growth dynamics of CO2 emissions. We show that the global growth of new renewable sources of energy post-1990 represents a climate-society feedback of ~0.25%yr-1 per degree increase in global mean temperature. We also show that to fulfil the outcomes negotiated in Durban in 2011, society will have to become ~ 50 times more responsive to global mean temperature change than it has been since 1990. If global energy use continues to grow as it has done historically then this would result in amplification of the long-term endogenous rate of decarbonization from -0.6%yr-1 to ~-13%yr-1. It is apparent that modest levels of feedback sensitivity pay large dividends in avoiding climate change but that the marginal return on this effort diminishes rapidly as the required feedback strength increases.

  8. Potential forest fire danger over Northern Eurasia: Changes during the 20th century

    NASA Astrophysics Data System (ADS)

    Sherstyukov, B. G.; Razuvaev, V. N.; Groisman, P. Y.; Knight, R. W.; Enloe, J. G.

    2004-12-01

    Significant climatic changes over Northern Eurasia during the 20th century have been reflected in numerous variables of economic, social, and ecological interests, including the natural frequency of forest fires. For the former USSR, we are now using the Global Daily Climatology Network (Gleason et al. 2002) and a new Global Synoptic Data Network archive, GSDN, created jointly by NCDC an RIHMI. Data from these archives are employed to estimate systematic changes in indices used in the United States and Russia to assess potential forest fire danger. Within the boundaries of the former USSR, each of the archives, GHCN and GSDN, includes more than 2100 stations with only approximately 1500 of them having sufficiently long meteorological time series suitable for participation in our analyses. We use three indices: (1) Keetch-Byram Drought Index, (KBDI; this index uses only daily data on maximum temperature and precipitation and is developed and widely used in the United States); (2) Modified Nesterov, and (3) Zhdanko Indices (these indices are developed and widely used in Russia; their computation requires synoptic daytime data on temperature and humidity and daily precipitation and snow on the ground). Analyses show that after calibration, time series of the days with increased potential forest fire danger constructed using each of these three indices (a) are well correlated and (b) deliver similar conclusions about systematic changes in the weather conditions conducive to forest fires. Specifically, over the entire Eastern half of Northern Eurasia (Siberia and the Russian Far East) we found a statistically significant increase in indices that characterize the weather conditions conducive to forest fires. These areas coincide with the areas of most significant warming during the past several decades south of the Arctic Circle. West of the Ural Mountains, the same indices show a steady decrease in the frequency of the "dry weather summer days" during the past sixty

  9. Living Dangerously--Changing Press Law in India.

    ERIC Educational Resources Information Center

    Ryan, Timothy

    An examination of the changes in press laws after India gained its independence in 1947 shows how a free press is shaped mostly by the structure and evolution of the democratic society that it is intended to serve. The most salient features that have characterized the Indian press, from the early nineteenth century to the present day, are…

  10. Changing Horses in Midstream: The Dangers of Unplanned Head Transitions

    ERIC Educational Resources Information Center

    Quinby, Lee

    2015-01-01

    Quick leadership transitions may succeed in other industries, but they don't usually work in the "business of relationships" we call school. Boards that respond to a solvable problem by firing the head may believe that action is necessary and good for the school. In truth, these abrupt changes almost always hurt schools, with devastating…

  11. Temporal variations and change of forest fire danger in Europe in 1960-2012

    NASA Astrophysics Data System (ADS)

    Venäläinen, A.; Korhonen, N.; Koutsias, N.; Xystrakis, F.; Urbieta, I. R.; Moreno, J. M.

    2013-11-01

    Understanding how fire-weather danger indices changed in the past, and detecting how changes affected forest fire activity is important in changing climate. We used the Canadian Fire Weather Index (FWI), calculated from two reanalysis datasets, ERA 40 and ERA Interim, to examine the temporal variation of forest fire danger in Europe in 1960-2012. Additionally, we used national forest-fires statistical data from Greece and Spain to relate fire danger and fire activity. There is no obvious trend in fire danger for the time period covered by ERA 40 (1960-1999) whereas for the period 1980-2012 covered by ERA Interim, the mean FWI and the number of high fire risk days shows an increasing trend which is significant at the 99% confidence level for South and East Europe. The cross-correlation calculated at national level in Greece and Spain between mean yearly area burned and mean FWI of the current season is of the order 0.5-0.6, and demonstrates the importance of the fire-season weather on forest fires. Our results show that, fire risk is multifaceted, and factors like changes in fire fighting capacity, ignition patterns, or landscapes might have played a role in forest fires trends. However, weather trends remain as important determinants of forest fires.

  12. Enzymatic temperature change indicator

    DOEpatents

    Klibanov, Alexander M.; Dordick, Jonathan S.

    1989-01-21

    A temperature change indicator is described which is composed of an enzyme and a substrate for that enzyme suspended in a solid organic solvent or mixture of solvents as a support medium. The organic solvent or solvents are chosen so as to melt at a specific temperature or in a specific temperature range. When the temperature of the indicator is elevated above the chosen, or critical temperature, the solid organic solvent support will melt, and the enzymatic reaction will occur, producing a visually detectable product which is stable to further temperature variation.

  13. The collective-risk social dilemma and the prevention of simulated dangerous climate change.

    PubMed

    Milinski, Manfred; Sommerfeld, Ralf D; Krambeck, Hans-Jürgen; Reed, Floyd A; Marotzke, Jochem

    2008-02-19

    Will a group of people reach a collective target through individual contributions when everyone suffers individually if the target is missed? This "collective-risk social dilemma" exists in various social scenarios, the globally most challenging one being the prevention of dangerous climate change. Reaching the collective target requires individual sacrifice, with benefits to all but no guarantee that others will also contribute. It even seems tempting to contribute less and save money to induce others to contribute more, hence the dilemma and the risk of failure. Here, we introduce the collective-risk social dilemma and simulate it in a controlled experiment: Will a group of people reach a fixed target sum through successive monetary contributions, when they know they will lose all their remaining money with a certain probability if they fail to reach the target sum? We find that, under high risk of simulated dangerous climate change, half of the groups succeed in reaching the target sum, whereas the others only marginally fail. When the risk of loss is only as high as the necessary average investment or even lower, the groups generally fail to reach the target sum. We conclude that one possible strategy to relieve the collective-risk dilemma in high-risk situations is to convince people that failure to invest enough is very likely to cause grave financial loss to the individual. Our analysis describes the social window humankind has to prevent dangerous climate change. PMID:18287081

  14. Dangerous climate change and the importance of adaptation for the Arctic's Inuit population

    NASA Astrophysics Data System (ADS)

    Ford, James D.

    2009-04-01

    The Arctic's climate is changing rapidly, to the extent that 'dangerous' climate change as defined by the United Nations Framework on Climate Change might already be occurring. These changes are having implications for the Arctic's Inuit population and are being exacerbated by the dependence of Inuit on biophysical resources for livelihoods and the low socio-economic-health status of many northern communities. Given the nature of current climate change and projections of a rapidly warming Arctic, climate policy assumes a particular importance for Inuit regions. This paper argues that efforts to stabilize and reduce greenhouse gas emissions are urgent if we are to avoid runaway climate change in the Arctic, but unlikely to prevent changes which will be dangerous for Inuit. In this context, a new policy discourse on climate change is required for Arctic regions—one that focuses on adaptation. The paper demonstrates that states with Inuit populations and the international community in general has obligations to assist Inuit to adapt to climate change through international human rights and climate change treaties. However, the adaptation deficit, in terms of what we know and what we need to know to facilitate successful adaptation, is particularly large in an Arctic context and limiting the ability to develop response options. Moreover, adaptation as an option of response to climate change is still marginal in policy negotiations and Inuit political actors have been slow to argue the need for adaptation assistance. A new focus on adaptation in both policy negotiations and scientific research is needed to enhance Inuit resilience and reduce vulnerability in a rapidly changing climate.

  15. Dangerous drivers foster social dilemma structures hidden behind a traffic flow with lane changes

    NASA Astrophysics Data System (ADS)

    Tanimoto, Jun; Fujiki, Takuya; Wang, Zhen; Hagishima, Aya; Ikegaya, Naoki

    2014-11-01

    Motivated by the fact that there are quite a few ill-mannered drivers who disregard traffic rules concerning lane-changing and maximum speed, we investigated an interesting question: whether or not social dilemma structures can be formed from a frequent dangerous lane-changing attitude in a typical traffic flow without any explicit bottlenecks. In our model system, two classes of driver-agents coexist: C agents (cooperative strategy) always keep to traffic regulations with respect to lane-changing and speed, while D agents (defective strategy) disregard them to move ahead. In relatively high-density flows, such as the metastable and high-density phases, we found structures that correspond to either n-person Prisoner's Dilemma (n-PD) games or to quasi-PD games. In these situations, existing ill-mannered drivers create heavy traffic jams that reduce social efficiency.

  16. Global temperature change

    PubMed Central

    Hansen, James; Sato, Makiko; Ruedy, Reto; Lo, Ken; Lea, David W.; Medina-Elizade, Martin

    2006-01-01

    Global surface temperature has increased ≈0.2°C per decade in the past 30 years, similar to the warming rate predicted in the 1980s in initial global climate model simulations with transient greenhouse gas changes. Warming is larger in the Western Equatorial Pacific than in the Eastern Equatorial Pacific over the past century, and we suggest that the increased West–East temperature gradient may have increased the likelihood of strong El Niños, such as those of 1983 and 1998. Comparison of measured sea surface temperatures in the Western Pacific with paleoclimate data suggests that this critical ocean region, and probably the planet as a whole, is approximately as warm now as at the Holocene maximum and within ≈1°C of the maximum temperature of the past million years. We conclude that global warming of more than ≈1°C, relative to 2000, will constitute “dangerous” climate change as judged from likely effects on sea level and extermination of species. PMID:17001018

  17. Potential forest fire danger over Northern Eurasia: Changes during the 20th century

    NASA Astrophysics Data System (ADS)

    Groisman, Pavel Ya.; Sherstyukov, Boris G.; Razuvaev, Vyacheslav N.; Knight, Richard W.; Enloe, Jesse G.; Stroumentova, Nina S.; Whitfield, Paul H.; Førland, Eirik; Hannsen-Bauer, Inger; Tuomenvirta, Heikki; Aleksandersson, Hans; Mescherskaya, Anna V.; Karl, Thomas R.

    2007-04-01

    Significant climatic changes over Northern Eurasia during the 20th century have been reflected in numerous variables of economic, social, and ecological interest, including the natural frequency of forest fires. For the former USSR, we are now using the Global Daily Climatology Network and a new Global Synoptic Data Network archive, GSDN, created jointly by U.S. National Climatic Data Center and Russian Research Institute for Hydrometeorological Information. Data from these archives (approximately 1500 of them having sufficiently long meteorological time series suitable for participation in our analyses) are employed to estimate systematic changes in indices used in the United States and Russia to assess potential forest fire danger. We use four indices: (1) Keetch-Byram Drought Index, (KBDI; this index was developed and widely used in the United States); (2) Nesterov, (3) Modified Nesterov, and (4) Zhdanko Indices (these indices were developed and widely used in Russia). Analyses show that after calibration, time series of the days with increased potential forest fire danger constructed using each of these three indices (a) are well correlated and (b) deliver similar conclusions about systematic changes in the weather conditions conducive to forest fires. Specifically, over the Eastern half of Northern Eurasia (Siberia and the Russian Far East) statistically significant increases in indices that characterize the weather conditions conducive to forest fires were found. These areas coincide with the areas of most significant warming during the past several decades south of the Arctic Circle. West of the Ural Mountains, the same indices show a steady decrease in the frequency of "dry weather summer days" during the past 60 yr. This study is corroborated with available statistics of forest fires and with observed changes in drought statistics in agricultural regions of Northern Eurasia.

  18. Embedded Temperature-Change Sensors

    NASA Technical Reports Server (NTRS)

    Thakoor, Sarita; Thakoor, Anil; Karmon, Dan

    1995-01-01

    Transducers sensitive to rates of change of temperature embedded in integrated circuits and discrete electronic components damaged by overheating, according to proposal. Used to detect onset of rapid heating and to trigger shutoffs of power or other corrective actions before temperatures rise beyond safe limits. Sensors respond fast and reliably to incipient overheating because they are in direct thermal contact with vulnerable circuit elements.

  19. Phase Change Fabrics Control Temperature

    NASA Technical Reports Server (NTRS)

    2009-01-01

    Originally featured in Spinoff in 1997, Outlast Technologies Inc. (formerly Gateway Technologies Inc.) has built its entire product line on microencapsulated phase change materials, developed in Small Business Innovation Research (SBIR) contracts with Johnson Space Center after initial development for the U.S. Air Force. The Boulder, Colorado-based company acquired the exclusive patent rights and now integrates these materials into textiles or onto finished apparel, providing temperature regulation in bedding materials and a full line of apparel for both ordinary and extreme conditions.

  20. The Danger of Selectively Changing the Rules in Youth Sport: The Case of the Strike Zone

    ERIC Educational Resources Information Center

    Torres, Cesar R.

    2010-01-01

    Albeit well-intentioned, the practice of selectively changing the strike zone to promote young players' welfare is critically flawed. After discussing the central purpose of competitive sport, the duty of officials, and the significance of impartiality in officiating, this article demonstrates that this practice presents numerous practical…

  1. [Dangerous aquaria].

    PubMed

    Satora, Leszek; Morawska, Jowanka; Szkolnicka, Beata; Mitrus, Małgorzata; Targosz, Dorota; Gwiazdowski, Andrzej

    2005-01-01

    World trends for a home breeding of exotic freshwater and marine fishes did not miss Poland. There are almost all species of aquarium fishes available in Polish pet shops, but there is not enough information about threat given to customers. In some fish, there are masses of one-cell glands, mainly serous, in the proximity of the spines. In others, those one-cell glands may be grouped in larger aggregates of cells called venom glands, that may form organs resembling multicellular glands of terrestrial animals. They are usually located around the spines or hard rays of the fins. Even if covered with a connective tissue sheath, the aggregates of the venom cells do not have any common outlet; they are not, therefore, proper multicellular glands. The venom glands of the catfish are covered with a thin sheath and they release their contents when the fin ray is pressed. Spines are derived from fin rays. When the spine penetrates the body of its prey, it presses its base against the cells, squashes them and squeezes the venomous contents into the wound. Catfish, lionfish and stonefish have the venom glands producing secretion which could be dangerous. The eels and morays blood is also dangerous, as well as slime of reduced squamae. Poison information centers noted several cases of fishes' stings in Poland. PMID:16225137

  2. Headaches - danger signs

    MedlinePlus

    Migraine headache - danger signs; Tension headache - danger signs; Cluster headache - danger signs; Vascular headache - danger signs ... and bleeding in the brain can cause a headache. These problems include: Abnormal connection between the arteries ...

  3. [Dangerous animals].

    PubMed

    Hasle, Gunnar

    2002-06-30

    As travellers seek ever more exotic destinations they are more likely to encounter dangerous animals. Compared to risks such as AIDS, traffic accidents and malaria, the risk is not so great; many travellers are, however, concerned about this and those who give pre-travel vaccines and advice should know something about it. This article is mainly based on medical and zoological textbooks. Venomous stings and bites may be prevented by adequate clothing and by keeping safe distance to the animals. Listening to those who live in the area is of course important. Travellers should not carry antisera with them, but antisera should be available at local hospitals. It should be borne in mind that plant eaters cause just as many deaths as large predators. In some cases it is necessary to carry a sufficiently powerful firearm. PMID:12555616

  4. Undulator Changes Due To Temperature Excursions

    SciTech Connect

    Wolf, Zachary; Levashov, Yurii; Reese, Ed; /SLAC

    2010-11-17

    The temperature of the LCLS undulators has not been controlled during storage. The effects of the temperature excursions are documented in this note. After a number of LCLS undulators were tuned, fiducialized, and placed in storage anticipating their use, a test was made to ensure that their properties had not changed. The test revealed, however, that indeed the undulators had changed. Detailed study of this problem followed. We now believe that the gap of the undulators changes permanently when the undulators go through temperature excursions. We have tested the other possible cause, transportation, and do not see gap changes. In this note, we document how the undulators have changed since they were originally tuned. The undulators were tuned and fiducialized in the Magnetic Measurement Facility (MMF). Afterward, many of them (approximately 18) were taken to building 750 for storage during summer and fall 2007. Building 750 had no temperature control. The undulator temperatures went from 20 C, used for tuning, down to approximately 11 C during the winter. In January 2008, three of the undulators were brought back to the MMF for a check. All three undulators showed similar changes. Trajectories, phases, and most undulator properties stayed the same, but the fiducialization (beam axis position relative to tooling balls on the undulator) had changed. Further investigation showed that the undulator gap was altered in a periodic way along the magnetic axis with a net average gap change causing the fiducialization change. A new storage location in building 33 was found and future undulators were placed there. A failure in the temperature control, however, caused the undulators to get too hot. Again the gap changed, but with a different periodic pattern. This note documents the measured changes in the undulators. In particular, it shows the detailed history of undulator 39 which went through both negative and positive temperature excursions.

  5. GISS Analysis of Surface Temperature Changes

    NASA Technical Reports Server (NTRS)

    Hansen, J.; Ruedy, R.; Glascoe, J.; Sato, M.

    1999-01-01

    We describe the current GISS analysis of surface temperature change based primarily on meteorological station measurements. The global surface temperature in 1998 was the warmest in the period of instrumental data. The rate of temperature change is higher in the past 25 years than at any previous time in the period of instrumental data. The warmth of 1998 is too large and pervasive to be fully accounted for by the recent El Nino, suggesting that global temperature may have moved to a higher level, analogous to the increase that occurred in the late 1970s. The warming in the United States over the past 50 years is smaller than in most of the world, and over that period there is a slight cooling trend in the Eastern United States and the neighboring Atlantic ocean. The spatial and temporal patterns of the temperature change suggest that more than one mechanism is involved in this regional cooling.

  6. GISS Analysis of Surface Temperature Change

    NASA Technical Reports Server (NTRS)

    Hansen, J.; Ruedy, R.; Glascoe, J.; Sato, M.

    1999-01-01

    We describe the current GISS analysis of surface temperature change for the period 1880-1999 based primarily on meteorological station measurements. The global surface temperature in 1998 was the warmest in the period of instrumental data. The rate of temperature change was higher in the past 25 years than at any previous time in the period of instrumental data. The warmth of 1998 was too large and pervasive to be fully accounted for by the recent El Nino. Despite cooling in the first half of 1999, we suggest that the mean global temperature, averaged over 2-3 years, has moved to a higher level, analogous to the increase that occurred in the late 1970s. Warming in the United States over the past 50 years has been smaller than in most of the world, and over that period there was a slight cooling trend in the Eastern United States and the neighboring Atlantic Ocean. The spatial and temporal patterns of the temperature change suggest that more than one mechanism was involved in this regional cooling. The cooling trend in the United States, which began after the 1930s and is associated with ocean temperature change patterns, began to reverse after 1979. We suggest that further warming in the United States to a level rivaling the 1930s is likely in the next decade, but reliable prediction requires better understanding of decadal oscillations of ocean temperature.

  7. [Dangerous games in schoolchildren].

    PubMed

    Le Heuzey, M-F

    2011-02-01

    Dangerous games inside or outside school are a serious social phenomenon, but unfortunately underrecognized. Aggressive games are a part of school bullying, which is in expansion. Choking games are very dangerous, with many deaths or serious neurologic complications. Pediatricians should be knowledgeable about risky behaviors encountered by their patients, and provide guidance about its dangers. PMID:21146376

  8. Wildfire Danger Potential in California

    NASA Astrophysics Data System (ADS)

    Kafatos, M.; Myoung, B.; Kim, S. H.; Fujioka, F. M.; Kim, J.

    2015-12-01

    Wildfires are an important concern in California (CA) which is characterized by the semi-arid to arid climate and vegetation types. Highly variable winter precipitation and extended hot and dry warm season in the region challenge an effective strategic fire management. Climatologically, the fire season which is based on live fuel moisture (LFM) of generally below 80% in Los Angeles County spans 4 months from mid-July to mid-November, but it has lasted over 7 months in the past several years. This behavior is primarily due to the ongoing drought in CA during the last decade, which is responsible for frequent outbreaks of severe wildfires in the region. Despite their importance, scientific advances for the recent changes in wildfire risk and effective assessments of wildfire risk are lacking. In the present study, we show impacts of large-scale atmospheric circulations on an early start and then extended length of fire seasons. For example, the strong relationships of North Atlantic Oscillation (NAO) with springtime temperature and precipitation in the SWUS that was recently revealed by our team members have led to an examination of the possible impact of NAO on wildfire danger in the spring. Our results show that the abnormally warm and dry spring conditions associated with positive NAO phases can cause an early start of a fire season and high fire risks throughout the summer and fall. For an effective fire danger assessment, we have tested the capability of satellite vegetation indices (VIs) in replicating in situ LFM of Southern CA chaparral ecosystems by 1) comparing seasonal/interannual characteristics of in-situ LFM with VIs and 2) developing an empirical model function of LFM. Unlike previous studies attempting a point-to-point comparison, we attempt to examine the LFM relationship with VIs averaged over different areal coverage with chamise-dominant grids (i.e., 0.5 km to 25 km radius circles). Lastly, we discuss implications of the results for fire danger

  9. Changes in Soil Temperature Regimes under Regional Climate Change

    NASA Astrophysics Data System (ADS)

    Millar, S. W.

    2013-12-01

    Soil temperatures can provide a smoothed record of regional changes in atmospheric conditions due to soil thermal properties that reduce the annual air and surface temperature amplitude. In areas with seasonal snow cover, however, its insulating effect isolates the soil thermal regime from winter air temperatures. Under changing regional climate patterns, snow cover extent, depth and duration are decreasing. The net effect is thus an expected winter cooling of soil temperature. However, the extent to which this might be mitigated by warmer summer conditions, and changing soil moisture remains to be seen. To examine the relative strength of a cold-season cooling signal versus enhanced summer warming, a network of soil temperature loggers has recorded hourly soil temperatures over the period 2005-2013 within a single watershed experiencing 'lake effect snow'. Elevations range from 168 m to 612 m, on Silurian and Ordovician shale, limestone, and sandstone that have been heavily glaciated. Most of the sites are located on NY Department of Environmental Conservation land in mixed, hardwood and spruce forests. At six sites in varied topographic and land-use setting, two ONSET HOBO Outdoor 4 channel soil temperature loggers are deployed in order to reduce concerns of data reliability and systematic logger drift. Five sites also record air temperature using HOBO Pro Series Temperature loggers at three sites and HOBO Weather Stations at two. Soil temperature data are recorded at hourly intervals at depths of 2-, 5-, 10-, and 25-cm. Several other sites have been operationalized over the 8 year period, but have been tampered with, damaged, stolen, or have failed. These partial records are included to provide greater geographic representation of changing conditions where possible. Data indicate decreasing winter soil temperatures in specific land-use and topographic settings. Only one site, located in a dense spruce plantation, experiences soil freezing within the top 5 cm

  10. Seasonal Changes in Surface Temperatures on Titan

    NASA Technical Reports Server (NTRS)

    Jennings, D. E.; Cottini, V.; Nixon, C. A.

    2010-01-01

    The surface brightness temperatures on Titan have been measured by the Composite Infrared Spectrometer (CIRS) aboard Cassini during the period spanning late northern winter through vernal equinox. CIRS observes radiance from the surface through a spectral window at 19 microns where the atmosphere has an opacity minimum [I]. CIRS is now seeing a shift in the latitudinal distribution of temperatures froth a distinctly warmer south to a more symmetrical north -south pattern, similar to that found by Voyager IRIS [2,3] at the time of the previous vernal equinox. Near the equator the temperatures remain close to the 93.7 K value found at the surface by Huygens [4]. From the equator to the poles the temperature gradients are 2-3 K. When compared with predictions froth general circulation models [5] the measured temperatures and their seasonal changes constrain the possible types of surface material. As Cassini continues through Titan's northern spring CiRS will extend its, global coverage to took for correlations between surface temperatures and albedo and to search for diurnal temperature variations

  11. Effects of temperature changes on groundwater ecosystems

    NASA Astrophysics Data System (ADS)

    Griebler, Christian; Kellermann, Claudia; Schreglmann, Kathrin; Lueders, Tillmann; Brielmann, Heike; Schmidt, Susanne; Kuntz, David; Walker-Hertkorn, Simone

    2014-05-01

    The use of groundwater as a carrier of thermal energy is becoming more and more important as a sustainable source of heating and cooling. At the same time, the present understanding of the effects of aquifer thermal usage on geochemical and biological aquifer ecosystem functions is extremely limited. Recently we started to assess the effects of temperature changes in groundwater on the ecological integrity of aquifers. In a field study, we have monitored hydrogeochemical, microbial, and faunal parameters in groundwater of an oligotrophic aquifer in the vicinity of an active thermal discharge facility. The observed seasonal variability of abiotic and biotic parameters between wells was considerable. Yet, due to the energy-limited conditions no significant temperature impacts on bacterial or faunal abundances and on bacterial productivity were observed. In contrast, the diversity of aquifer bacterial communities and invertebrate fauna was either positively or negatively affected by temperature, respectively. In follow-up laboratory experiments temperature effects were systematically evaluated with respect to energy limitation (e.g. establishment of unlimited growth conditions), geochemistry (e.g. dynamics of DOC and nutrients), microbiology (e.g. survival of pathogens), and fauna (temperature preference and tolerance). First, with increased nutrient and organic carbon concentrations even small temperature changes revealed microbiological dynamics. Second, considerable amounts of adsorbed DOC were mobilized from sediments of different origin with an increase in temperatures. No evidence was obtained for growth of pathogenic bacteria and extended survival of viruses at elevated temperatures. Invertebrates clearly preferred natural thermal conditions (10-12°C), where their highest frequency of appearance was measured in a temperature gradient. Short-term incubations (48h) of invertebrates in temperature dose-response tests resulted in LT50 (lethal temperature) values

  12. Changes in Concurrent Precipitation and Temperature Extremes

    SciTech Connect

    Hao, Zengchao; AghaKouchak, Amir; Phillips, Thomas J.

    2013-08-01

    While numerous studies have addressed changes in climate extremes, analyses of concurrence of climate extremes are scarce, and climate change effects on joint extremes are rarely considered. This study assesses the occurrence of joint (concurrent) monthly continental precipitation and temperature extremes in Climate Research Unit (CRU) and University of Delaware (UD) observations, and in 13 Coupled Model Intercomparison Project Phase 5 (CMIP5) global climate simulations. Moreover, the joint occurrences of precipitation and temperature extremes simulated by CMIP5 climate models are compared with those derived from the CRU and UD observations for warm/wet, warm/dry, cold/wet, and cold/dry combinations of joint extremes. The number of occurrences of these four combinations during the second half of the 20th century (1951–2004) is assessed on a common global grid. CRU and UD observations show substantial increases in the occurrence of joint warm/dry and warm/wet combinations for the period 1978–2004 relative to 1951–1977. The results show that with respect to the sign of change in the concurrent extremes, the CMIP5 climate model simulations are in reasonable overall agreement with observations. The results reveal notable discrepancies between regional patterns and the magnitude of change in individual climate model simulations relative to the observations of precipitation and temperature.

  13. Changes in Concurrent Precipitation and Temperature Extremes

    DOE PAGESBeta

    Hao, Zengchao; AghaKouchak, Amir; Phillips, Thomas J.

    2013-08-01

    While numerous studies have addressed changes in climate extremes, analyses of concurrence of climate extremes are scarce, and climate change effects on joint extremes are rarely considered. This study assesses the occurrence of joint (concurrent) monthly continental precipitation and temperature extremes in Climate Research Unit (CRU) and University of Delaware (UD) observations, and in 13 Coupled Model Intercomparison Project Phase 5 (CMIP5) global climate simulations. Moreover, the joint occurrences of precipitation and temperature extremes simulated by CMIP5 climate models are compared with those derived from the CRU and UD observations for warm/wet, warm/dry, cold/wet, and cold/dry combinations of joint extremes.more » The number of occurrences of these four combinations during the second half of the 20th century (1951–2004) is assessed on a common global grid. CRU and UD observations show substantial increases in the occurrence of joint warm/dry and warm/wet combinations for the period 1978–2004 relative to 1951–1977. The results show that with respect to the sign of change in the concurrent extremes, the CMIP5 climate model simulations are in reasonable overall agreement with observations. The results reveal notable discrepancies between regional patterns and the magnitude of change in individual climate model simulations relative to the observations of precipitation and temperature.« less

  14. SEASONAL CHANGES IN TITAN'S SURFACE TEMPERATURES

    SciTech Connect

    Jennings, D. E.; Cottini, V.; Nixon, C. A.; Flasar, F. M.; Kunde, V. G.; Samuelson, R. E.; Romani, P. N.; Hesman, B. E.; Carlson, R. C.; Gorius, N. J. P.; Coustenis, A.; Tokano, T.

    2011-08-10

    Seasonal changes in Titan's surface brightness temperatures have been observed by Cassini in the thermal infrared. The Composite Infrared Spectrometer measured surface radiances at 19 {mu}m in two time periods: one in late northern winter (LNW; L{sub s} = 335 deg.) and another centered on northern spring equinox (NSE; L{sub s} = 0 deg.). In both periods we constructed pole-to-pole maps of zonally averaged brightness temperatures corrected for effects of the atmosphere. Between LNW and NSE a shift occurred in the temperature distribution, characterized by a warming of {approx}0.5 K in the north and a cooling by about the same amount in the south. At equinox the polar surface temperatures were both near 91 K and the equator was at 93.4 K. We measured a seasonal lag of {Delta}L{sub S} {approx} 9{sup 0} in the meridional surface temperature distribution, consistent with the post-equinox results of Voyager 1 as well as with predictions from general circulation modeling. A slightly elevated temperature is observed at 65{sup 0} S in the relatively cloud-free zone between the mid-latitude and southern cloud regions.

  15. Seasonal Changes in Titan's Surface Temperatures

    NASA Technical Reports Server (NTRS)

    Jennins, Donald E.; Cottini, V.; Nixon, C. A.; Flasar, F. M.; Kunde, V. G.; Samuelson, R. E.; Romani, P. N.; Hesman, B. E.; Carlson, R. C.; Gorius, N. J. P.; Coustenis, A.; Tokano, T.

    2011-01-01

    Seasonal changes in Titan's surface brightness temperatures have been observed by Cassini in the thermal infrared. The Composite Infrared Spectrometer (CIRS) measured surface radiances at 19 micron in two time periods: one in late northern winter (Ls = 335d eg) and another centered on northern spring equinox (Ls = 0 deg). In both periods we constructed pole-to-pole maps of zonally averaged brightness temperatures corrected for effects of the atmosphere. Between late northern winter and northern spring equinox a shift occurred in the temperature distribution, characterized by a warming of approximately 0.5 K in the north and a cooling by about the same amount in the south. At equinox the polar surface temperatures were both near 91 K and the equator was 93.4 K. We measured a seasonal lag of delta Ls approximately 9 in the meridional surface temperature distribution, consistent with the post-equinox results of Voyager 1 as well as with predictions from general circulation modeling. A slightly elevated temperature is observed at 65 deg S in the relatively cloud-free zone between the mid-latitude and southern cloud regions.

  16. Dangerous marine life.

    PubMed

    Harrison, L J

    1992-09-01

    All physicians must be educated in treating injuries incurred when a diver comes into contact with any dangerous marine life. Stinging invertebrates are the most commonly encountered dangerous marine animals. Venomous vertebrate marine animals are less common than stinging invertebrates and easier to recognize. However, they may be much more deadly. Sharks pose the greatest danger to divers. However, bites from other marine animals can be painful, become infected and require extensive medical treatment. PMID:1358999

  17. Fitting the observed changes of global surface temperatures

    NASA Astrophysics Data System (ADS)

    Courtillot, V.; Le Mouël, J.; Kossobokov, V. G.; Gibert, D.; Lopes, F.

    2012-12-01

    The quality of the fit of a trivial or, conversely, delicately-designed model to the observed natural phenomena is the fundamental pillar stone of any forecasting, including forecasting of the Earth's Climate. Using precise mathematical and logical systems outside their range of applicability can be scientifically groundless, unwise, and even dangerous. The temperature data sets are naturally in the basis of any hypothesizing on variability and forecasting the Earth's Climate. Leaving open the question of the global temperature definitions and their determination (T), we have analyzed hemispheric and global monthly temperature anomaly series produced by the Climate Research Unit of the University of East Anglia (CRUTEM4 database) and more recently by the Berkeley Earth Surface Temperature consortium (BEST database). We first fit the data in 1850-2010 with polynomials of degrees 1 to 9 and compare it with exponential fit by the adjusted R-squared criterion that takes into consideration the number of free parameters of the model. In all the cases considered, the adjusted R-squared values for polynomials are larger than for the exponential as soon as the degree exceeds 1 or 2. The polynomial fits become even more satisfactory as soon as degree 5 or 6 is reached. Extrapolations of these trends outside of the data domain show quick divergence. For example, the CRUTEM4vNH fit in the decade 2010-2020, for degrees 2 to 5, rises steeply then, for degrees 6 to 9, reverses to steep decreasing: the reversal in extrapolated trends arises from improved ability to fit the observed "~60-yr" wave in 150 years of data prior to 2010. The extrapolations prior to 1850 are even more erratic, linked with the increased dispersion of the early data. When focusing the analysis of fits on 1900-2010 we find that the apparent oscillations of T can be modeled by a series of linear segments: An optimal fit suggests 4 slope breaks indicating two clear transitions in 1940 and 1975, and two that

  18. Seasonal Changes in Titan's Surface Temperatures

    NASA Technical Reports Server (NTRS)

    Jennings, Donald E.; Nixon, Conor A.; Cottini, Valeria

    2011-01-01

    Cassini's extended mission has provided the opportunity to search for seasonal variations on Titan. In particular, surface temperatures are expected to have shifted significantly in latitude during the completed portion of the mission. Spectra recorded by the Composite Infrared Spectrometer (CIRS) during the nominal mission (2004-08) and the Equinox mission. (2008-10) have already shown changes in temperature. CIRS has detected a seasonal shift in the latitudinal distribution of surface brightness temperatures by comparing zonal averages from two time segments, one period in late northern winter centered on L(sub s) approximately 335 deg and a second period centered on the equinox (L(sub s) approximately 0 deg.). The earlier period had a meridional distribution similar to that previously reported: 93.5 K at the equator, 91.7 K at 85 S and 899 K at 85 N. The newly measured distribution near equinox shows a cooling in the south and a warming in the north, both by about 0.5 K. We estimate that. the centroid of the distribution moved from approximately 16 S to 7 S between the two periods. This gives a seasonal lag behind insolation of delta L(sub s) approximately 13 deg. The CIRS equinox results are consistent with those of Voyager IRIS, which encountered Titan in November 1980, just following the previous northern equinox (L(sub s) = 10 deg.). When compared with predictions from general circulation models, seasonal variations of surface temperature can help constrain the identification of surface materials. Our measurements most closely match the case of a porous ice regolith treated by Tokano, but with some apparent differences between the northern and southern hemispheres. CIRS will extend its study of seasonal variations in surface temperature on Titan as Cassini continues through northern spring.

  19. Assessing 'Dangerous Climate Change': Required Reduction of Carbon Emissions to Protect Young People, Future Generations and Nature

    NASA Technical Reports Server (NTRS)

    Hansen, James; Kharecha, Pushker; Sato, Makiko; Masson-Demotte, Valerie; Ackerman, Frank; Beerling, David J.; Hearty, Paul J.; Hoegh-Guldberg, Ove; Hsu, Shi-Ling; Parmesan, Camille; Rockstrum, Johan; Rohling, Eelco J.; Sachs, Jeffrey; Smith, Pete; Steffen, Conrad; VanSusteren, Lise; VonShuckmann, Karina; Zachos, James C.

    2013-01-01

    We assess climate impacts of global warming using ongoing observations and paleoclimate data. We use Earth's measured energy imbalance, paleoclimate data, and simple representations of the global carbon cycle and temperature to define emission reductions needed to stabilize climate and avoid potentially disastrous impacts on today's young people, future generations, and nature. A cumulative industrial-era limit of approx.500 GtC fossil fuel emissions and 100 GtC storage in the biosphere and soil would keep climate close to the Holocene range to which humanity and other species are adapted. Cumulative emissions of approx.1000 GtC, sometimes associated with 2 C global warming, would spur "slow" feedbacks and eventual warming of 3-4 C with disastrous consequences. Rapid emissions reduction is required to restore Earth's energy balance and avoid ocean heat uptake that would practically guarantee irreversible effects. Continuation of high fossil fuel emissions, given current knowledge of the consequences, would be an act of extraordinary witting intergenerational injustice. Responsible policymaking requires a rising price on carbon emissions that would preclude emissions from most remaining coal and unconventional fossil fuels and phase down emissions from conventional fossil fuels.

  20. Assessing "dangerous climate change": required reduction of carbon emissions to protect young people, future generations and nature.

    PubMed

    Hansen, James; Kharecha, Pushker; Sato, Makiko; Masson-Delmotte, Valerie; Ackerman, Frank; Beerling, David J; Hearty, Paul J; Hoegh-Guldberg, Ove; Hsu, Shi-Ling; Parmesan, Camille; Rockstrom, Johan; Rohling, Eelco J; Sachs, Jeffrey; Smith, Pete; Steffen, Konrad; Van Susteren, Lise; von Schuckmann, Karina; Zachos, James C

    2013-01-01

    We assess climate impacts of global warming using ongoing observations and paleoclimate data. We use Earth's measured energy imbalance, paleoclimate data, and simple representations of the global carbon cycle and temperature to define emission reductions needed to stabilize climate and avoid potentially disastrous impacts on today's young people, future generations, and nature. A cumulative industrial-era limit of ∼500 GtC fossil fuel emissions and 100 GtC storage in the biosphere and soil would keep climate close to the Holocene range to which humanity and other species are adapted. Cumulative emissions of ∼1000 GtC, sometimes associated with 2°C global warming, would spur "slow" feedbacks and eventual warming of 3-4°C with disastrous consequences. Rapid emissions reduction is required to restore Earth's energy balance and avoid ocean heat uptake that would practically guarantee irreversible effects. Continuation of high fossil fuel emissions, given current knowledge of the consequences, would be an act of extraordinary witting intergenerational injustice. Responsible policymaking requires a rising price on carbon emissions that would preclude emissions from most remaining coal and unconventional fossil fuels and phase down emissions from conventional fossil fuels. PMID:24312568

  1. Stratospheric Temperature Changes: Observations and Model Simulations

    NASA Technical Reports Server (NTRS)

    Ramaswamy, V.; Chanin, M.-L.; Angell, J.; Barnett, J.; Gaffen, D.; Gelman, M.; Keckhut, P.; Koshelkov, Y.; Labitzke, K.; Lin, J.-J. R.

    1999-01-01

    This paper reviews observations of stratospheric temperatures that have been made over a period of several decades. Those observed temperatures have been used to assess variations and trends in stratospheric temperatures. A wide range of observation datasets have been used, comprising measurements by radiosonde (1940s to the present), satellite (1979 - present), lidar (1979 - present) and rocketsonde (periods varying with location, but most terminating by about the mid-1990s). In addition, trends have also been assessed from meteorological analyses, based on radiosonde and/or satellite data, and products based on assimilating observations into a general circulation model. Radiosonde and satellite data indicate a cooling trend of the annual-mean lower stratosphere since about 1980. Over the period 1979-1994, the trend is 0.6K/decade. For the period prior to 1980, the radiosonde data exhibit a substantially weaker long-term cooling trend. In the northern hemisphere, the cooling trend is about 0.75K/decade in the lower stratosphere, with a reduction in the cooling in mid-stratosphere (near 35 km), and increased cooling in the upper stratosphere (approximately 2 K per decade at 50 km). Model simulations indicate that the depletion of lower stratospheric ozone is the dominant factor in the observed lower stratospheric cooling. In the middle and upper stratosphere both the well-mixed greenhouse gases (such as CO) and ozone changes contribute in an important manner to the cooling.

  2. Relative outcomes of climate change mitigation related to global temperature versus sea-level rise

    NASA Astrophysics Data System (ADS)

    Meehl, Gerald A.; Hu, Aixue; Tebaldi, Claudia; Arblaster, Julie M.; Washington, Warren M.; Teng, Haiyan; Sanderson, Benjamin M.; Ault, Toby; Strand, Warren G.; White, James B.

    2012-08-01

    There is a common perception that, if human societies make the significant adjustments necessary to substantively cut emissions of greenhouse gases, global temperature increases could be stabilized, and the most dangerous consequences of climate change could be avoided. Here we show results from global coupled climate model simulations with the new representative concentration pathway mitigation scenarios to 2300 to illustrate that, with aggressive mitigation in two of the scenarios, globally averaged temperature increase indeed could be stabilized either below 2 °C or near 3 °C above pre-industrial values. However, even as temperatures stabilize, sea level would continue to rise. With little mitigation, future sea-level rise would be large and continue unabated for centuries. Though sea-level rise cannot be stopped for at least the next several hundred years, with aggressive mitigation it can be slowed down, and this would buy time for adaptation measures to be adopted.

  3. Colored Contact Lens Dangers

    MedlinePlus

    ... Halloween Hazard: The Hidden Dangers of Buying Decorative Contact Lenses Without a Prescription Sep. 26, 2013 It ... she first put in a pair of colored contact lenses, Laura Butler of Parkersburg, W.Va., had " ...

  4. Beyond the Mean: Biological Impacts of Cryptic Temperature Change.

    PubMed

    Sheldon, Kimberly S; Dillon, Michael E

    2016-07-01

    Studies have typically used shifts in mean temperatures to make predictions about the biotic impacts of climate change. Though shifts in mean temperatures correlate with changes in phenology and distributions, other hidden, or cryptic, changes in temperature, such as temperature variation and extreme temperatures, could pose greater risks to species and ecological communities. Yet, these cryptic temperature changes have received relatively little attention because mean temperatures are readily available and the organism-appropriate temperature response is often elusive. An alternative to using mean temperatures is to view organisms as physiological filters of hourly temperature data. We explored three classes of physiological filters: (1) nonlinear thermal responses using performance curves of insect fitness, (2) cumulative thermal effects using degree-day models for corn emergence, and (3) threshold temperature effects using critical thermal maxima and minima for diverse ectotherms. For all three physiological filters, we determined the change in biological impacts of hourly temperature data from a standard reference period (1961-90) to a current period (2005-10). We then examined how well mean temperature changes during the same time period predicted the biotic impacts we determined from hourly temperature data. In all cases, mean temperature alone provided poor predictions of the impacts of climate change. These results suggest that incorporating high frequency temperature data can provide better predictions for how species will respond to temperature change. PMID:27081192

  5. A Danger-Theory-Based Immune Network Optimization Algorithm

    PubMed Central

    Li, Tao; Xiao, Xin; Shi, Yuanquan

    2013-01-01

    Existing artificial immune optimization algorithms reflect a number of shortcomings, such as premature convergence and poor local search ability. This paper proposes a danger-theory-based immune network optimization algorithm, named dt-aiNet. The danger theory emphasizes that danger signals generated from changes of environments will guide different levels of immune responses, and the areas around danger signals are called danger zones. By defining the danger zone to calculate danger signals for each antibody, the algorithm adjusts antibodies' concentrations through its own danger signals and then triggers immune responses of self-regulation. So the population diversity can be maintained. Experimental results show that the algorithm has more advantages in the solution quality and diversity of the population. Compared with influential optimization algorithms, CLONALG, opt-aiNet, and dopt-aiNet, the algorithm has smaller error values and higher success rates and can find solutions to meet the accuracies within the specified function evaluation times. PMID:23483853

  6. Temperature Trapping: Energy-Free Maintenance of Constant Temperatures as Ambient Temperature Gradients Change

    NASA Astrophysics Data System (ADS)

    Shen, Xiangying; Li, Ying; Jiang, Chaoran; Huang, Jiping

    2016-07-01

    It is crucial to maintain constant temperatures in an energy-efficient way. Here we establish a temperature-trapping theory for asymmetric phase-transition materials with thermally responsive thermal conductivities. Then we theoretically introduce and experimentally demonstrate a concept of an energy-free thermostat within ambient temperature gradients. The thermostat is capable of self-maintaining a desired constant temperature without the need of consuming energy even though the environmental temperature gradient varies in a large range. As a model application of the concept, we design and show a different type of thermal cloak that has a constant temperature inside its central region in spite of the changing ambient temperature gradient, which is in sharp contrast to all the existing thermal cloaks. This work has relevance to energy-saving heat preservation, and it provides guidance both for manipulating heat flow without energy consumption and for designing new metamaterials with temperature-responsive or field-responsive parameters in many disciplines such as thermotics, optics, electromagnetics, acoustics, mechanics, electrics, and magnetism.

  7. Temperature Trapping: Energy-Free Maintenance of Constant Temperatures as Ambient Temperature Gradients Change.

    PubMed

    Shen, Xiangying; Li, Ying; Jiang, Chaoran; Huang, Jiping

    2016-07-29

    It is crucial to maintain constant temperatures in an energy-efficient way. Here we establish a temperature-trapping theory for asymmetric phase-transition materials with thermally responsive thermal conductivities. Then we theoretically introduce and experimentally demonstrate a concept of an energy-free thermostat within ambient temperature gradients. The thermostat is capable of self-maintaining a desired constant temperature without the need of consuming energy even though the environmental temperature gradient varies in a large range. As a model application of the concept, we design and show a different type of thermal cloak that has a constant temperature inside its central region in spite of the changing ambient temperature gradient, which is in sharp contrast to all the existing thermal cloaks. This work has relevance to energy-saving heat preservation, and it provides guidance both for manipulating heat flow without energy consumption and for designing new metamaterials with temperature-responsive or field-responsive parameters in many disciplines such as thermotics, optics, electromagnetics, acoustics, mechanics, electrics, and magnetism. PMID:27517778

  8. [Dangerous, illegal captivities].

    PubMed

    Winnik, Lidia; Lis, Leszek

    2005-01-01

    On the 21st of August 1997 the Polish legislature introduced the first animal protection law nr 724. This act however failed to specify in a clear and proper manner the problem of possession and maintenance of dangerous animals, which allows its multiple interpretations. Poland ratified the Washington Convention in 1990 restricting the trade of animals classified as endangered species. The present regulations enable illegal purchase and trade of those animals. According to the available data illegal trade of such animals, as well as the trade of products obtained from them, ranks in the third position in terms of crime generated income, only after the trade of drugs and weapons. In our country the sales of such animals have been growing at an alarming rate. The animals often get out of the control of their owners, or are abandoned by them. The presented work describes cases of reptiles being found in public places in our region. It also mentions the problem of possible dangers associated with intentional letting out of such animals in public places. The aim of the following paper is the analysis of the problem of raising of exotic animals, in particular venomous snakes and other animals, the possession of which may be dangerous not only for the owner but also for the people around. The existing laws and executive procedures have been discussed. Both, the family doctors as well as toxicologists have little knowledge as far as diagnosis and treatment of cases of stinging and biting by exotic animals is concerned. The authors suggest providing medical emergency doctors, family doctors and surgeons, with clinic toxicology programs, as well as introduction of special courses for middle medical personnel. Establishment of a central database and a database concerned with basic polyvalent serums are crucial in our country in order have the Toxicology Centers ready to face possible dangers associated with dangerous animals, and to prepare emergency solutions in cases of

  9. Dangers of the vagina.

    PubMed

    Beit-Hallahmi, B

    1985-12-01

    Beliefs, myths, and literary expressions of men's fear of female genitals are reviewed. Both clinical evidence and folklore provide evidence that men imagine female genitals not only as a source of pleasure and attraction, but also as a source of danger in a very physical sense. The vagina dentata myth has many versions, including some modern ones, and its message is always the same: an awesome danger emanating from a woman's body. The prevalence of such feelings in folklore and in literature is noted. PMID:3841494

  10. A Danger to Ourselves

    ERIC Educational Resources Information Center

    Barbieri, Richard

    2013-01-01

    In this article Richard Barbieri asserts that the biggest danger to our own safety and well-being, and that of our children, comes not from adult predators, environmental hazards, or the class bully, but from traits common to us all. The enemy is us, and not least because we too often jump to such strategies as clobbering. Writers from such varied…

  11. Reflections on Dangerous Fieldwork.

    ERIC Educational Resources Information Center

    Peritore, N. Patrick

    1990-01-01

    Stresses the danger of sociological fieldwork in Latin America for researcher and subject. Recommends that the researcher build a network of contacts for support and protection. Discusses the interpersonal relations, problems of security, and field entry techniques involved in sensitive research situations. Suggests unobtrusive methods of research…

  12. Radon: The Silent Danger.

    ERIC Educational Resources Information Center

    Stoffel, Jennifer

    1989-01-01

    This article discusses the public health dangers associated with radon exposure in homes and schools. In addition, testing and corrective efforts by federal and state agencies are discussed. A map indicating areas in the U.S. with potentially high radon levels is included. (IAH)

  13. Noble Gas Temperature Proxy for Climate Change

    EPA Science Inventory

    Noble gases in groundwater appear to offer a practical approach for quantitatively determining past surface air temperatures over recharge areas for any watershed. The noble gas temperature (NGT) proxy should then permit a paleothermometry of a region over time. This terrestria...

  14. Sensitivity of flowering phenology to changing temperature in China

    NASA Astrophysics Data System (ADS)

    Zhang, Haicheng; Yuan, Wenping; Liu, Shuguang; Dong, Wenjie; Fu, Yang

    2015-08-01

    Plant phenology is one of the preferred indicators of climate change, and its variation potentially impacts community dynamics and ecosystem functions. To better understand the responses of plants' flowering phenology to rising temperatures, we investigated the temperature sensitivity (expressed as the date of changes in phenology per change in temperature in degree Celsius, d °C-1) of flowering phenology for more than 220 plant species at 59 sites in China during the period 1963-1988. Our results indicated that most flowerings in China were significantly sensitive to the temperature in the 2 months (60 days) prior to the flowering dates. Plants in warmer regions showed larger sensitivities to increased temperatures. Species flowering in the late spring and early summer were generally less sensitive to changing temperature than species flowering at other times of the year. For plants flowering in the spring, species that flower earlier showed higher temperature sensitivity; however, for plants flowering in the summer and autumn, species that flower earlier showed lower temperature sensitivity. The responses of the first and last flowering times to changing temperature were mostly consistent, so flowering durations were rarely (6.1%) sensitive to changing temperature. We hypothesize that plants in cold regions may have adapted to the more variable temperatures and thus showed lower temperature sensitivities than plants in warm regions. Overall, the responses of flowering phenology to temperature varied significantly among temperature zones and plant species, so it should be considered carefully when estimating the impacts of climate warming on the terrestrial biosphere.

  15. Assessing stream temperature response to environmental change

    NASA Astrophysics Data System (ADS)

    MacDonald, R. J.; Boon, S.; Byrne, J. M.

    2010-12-01

    Stream temperature controls aquatic ecosystem function by directly influencing water quality, ecosystem productivity, and the physiological functioning of aquatic organisms. To date, there are limited studies of the impacts of environmental disturbance on stream temperature, particularly on the eastern slopes of the Rocky Mountains. This region provides key habitat for native salmonid species such as westslope cutthroat trout (Oncorhynchus clarkii lewisi) and bull trout (Salvelinus confluentus), which are listed as ‘threatened’ and ‘species of special concern’, respectively. Increases in stream temperature could limit habitat availability, reduce competitive advantage, and potentially increase mortality rates for these native species. This study uses field data collected at high spatiotemporal resolution to develop a spatial stream temperature model that simulates the mass and energy balance of the stream system. Preliminary field results demonstrate the high spatial and temporal variability in processes governing stream temperature in three study stream reaches. Groundwater/surface water interactions, topographic setting, and local meteorological conditions all contribute in determining stream thermal regimes. This work discusses how these primary drivers of stream temperature can be incorporated into a physically based spatial model, and demonstrates how depending on the scale of interest, the temperature of a stream can be governed by very different contributing factors.

  16. Seasonal Surface Temperature Changes on Titan

    NASA Astrophysics Data System (ADS)

    Jennings, Donald E.; Cottini, Valeria; Nixon, Conor A.; Coustenis, Athena; Tokano, Tetsuya

    2015-11-01

    The Composite Infrared Spectrometer (CIRS) on Cassini has been measuring surface brightness temperatures on Titan since 2004 (Jennings et al. 2011; Cottini et al. 2012; Tan et al. 2015). Radiation from the surface reaches space through a window of minimum opacity in Titan’s atmosphere near 19 microns wavelength. We mapped surface temperatures in five time periods, each about 2 years, centered on solar longitudes Ls = 313°, 335°, 0°, 28° and 53° degrees. Using zonally-averaged spectra binned in 10-degree latitude intervals, we clearly see the seasonal progression of the pole-to-pole temperature distribution. Whereas peak temperatures in the vicinity of the Equator have been close to 94 K throughout the Cassini mission, early in the mission temperatures at the North Pole were as low as 90 K and at the South Pole were 92 K. Late in the mission the pattern has reversed: 92 K in the north and 90 K in the south. Over 2005 to 2014 the peak temperature moved in latitude from about 15 S to 15 N. We estimate a seasonal lag of 0.2 Titan month. In 2010 the temperature distribution was approximately symmetric north and south, agreeing with Voyager 1 from one Titan year earlier. The surface temperatures follow closely the predictions of Tokano (2005). Our measurements may indicate a lower thermal inertia in the south than in the north.Jennings, D.E. et al., ApJ Lett. 737, L15 (2011)Cottini, V. et al., 2012. Planet. Space Sci. 60, 62 (2012)Tan, S. P. et al., Icarus 250, 64 (2015)Tokano, T., Icarus 204, 619 (2005)

  17. Effect of temperature change on anammox activity.

    PubMed

    Lotti, T; Kleerebezem, R; van Loosdrecht, M C M

    2015-01-01

    Autotrophic nitrogen removal appears as a prerequisite for the implementation of energy autarchic municipal wastewater treatment plants. Whilst the application of anammox-related technologies in the side-stream is at present state of the art, the feasibility of this energy-efficient process in main-stream conditions is still under investigation. Lower operating temperatures and ammonium concentrations, together with a demand for high and stable nitrogen removal efficiency, represent the main challenges to overcome for this appealing new frontier of the wastewater treatment field. In this study, we report the short-term effect of temperature on the maximum biomass specific activity of anaerobic ammonium oxidizing (anammox) bacteria as evaluated by means of batch tests. The experiments were performed on anammox biomass sampled from two full-scale reactors and two lab-scale reactors, all characterized by different reactor configurations and operating conditions. The results indicate that for the anammox conversion, the temperature dependency cannot be accurately modeled by one single Arrhenius coefficient (i.e., θ) as typically applied for other biological processes. The temperature effect is increasing at lower temperatures. Adaptation of anammox bacteria after long-term cultivation at 20 and 10°C was observed. Implications for modeling and process design are finally discussed. PMID:25042674

  18. Recording Rapidly Changing Cylinder-wall Temperatures

    NASA Technical Reports Server (NTRS)

    Meier, Adolph

    1942-01-01

    The present report deals with the design and testing of a measuring plug suggested by H. Pfriem for recording quasi-stationary cylinder wall temperatures. The new device is a resistance thermometer, the temperature-susceptible part of which consists of a gold coating applied by evaporation under high vacuum and electrolytically strengthened. After overcoming initial difficulties, calibration of plugs up to and beyond 400 degrees C was possible. The measurements were made on high-speed internal combustion engines. The increasing effect of carbon deposit at the wall surface with increasing operating period is indicated by means of charts.

  19. Potential dangers of cannabis.

    PubMed

    Kaymakçalan, S

    1975-01-01

    Cannabis is not a harmless drug. The potential dangers of cannabis are briefly reviewed in this report. The above-mentioned observations on cannabis users should be kept in mind and carefully examined by all physicians. One could expect that as more potent cannabis preparations become available, some of the toxic manifestations which now seem rare might become more frequent. Some of the remarks about the dangers of cannabis may not be proved in future studies, and they may represent only our anxiety. However, prior to the elimination of these fears, no steps should be taken toward the legalizing of marijuana. At present there is no scientific evidence that cannabis is less harmful than either tobacco or alcohol. The opposite may be true. The analogy can be drawn between opium and cannabis. The permissive attitude toward the use of opium can easily lead to the use of morphine and other opiates. If we legalize the use of marijuana, we cannot prevent the use of more dangerous derivatives of cannabis; namely, hashish, cannabis oil and THC, itself. In my opinion, in the light of our present knowledge, legalizing of marijuana could be hazardous both for the individual and for society. PMID:1181294

  20. Perceived temperature in the course of climate change: an analysis of global heat index from 1979-2013

    NASA Astrophysics Data System (ADS)

    Lee, D.; Brenner, T.

    2015-03-01

    The increase in global mean temperatures resulting from climate change has wide reaching consequences for the earth's ecosystems and other natural systems. Many studies have been devoted to evaluating the distribution and effects of these changes. We go a step further and evaluate global changes to the heat index, a measure of temperature as perceived by humans. Heat index, which is computed from temperature and relative humidity, is more important than temperature for the health of humans and other animals. Even in cases where the heat index does not reach dangerous levels from a health perspective, it has been shown to be an important factor in worker productivity and thus in economic productivity. We compute heat index from dewpoint temperature and absolute temperature 2 m above ground from the ERA-Interim reanalysis dataset for the years 1979-2013. The data is provided aggregated to daily minima, means and maxima (doi:10.1594/PANGAEA.841057). Furthermore, the data is temporally aggregated to monthly and yearly values and spatially aggregated to the level of countries after being weighted by population density in order to demonstrate its usefulness for the analysis of its impact on human health and productivity. The resulting data deliver insights into the spatiotemporal development of near-ground heat index during the course of the past 3 decades. It is shown that the impact of changing heat index is unevenly distributed through space and time, affecting some areas differently than others. The likelihood of dangerous heat index events has increased globally. Also, heat index climate groups that would formerly be expected closer to the tropics have spread latitudinally to include areas closer to the poles. The data can serve in future studies as a basis for evaluating and understanding the evolution of heat index in the course of climate change, as well as its impact on human health and productivity.

  1. Temperature, global climate change and food security

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Accelerated climate change is expected to have a significant, but variable impact on the world’s major cropping zones. Crops will experience increasingly warmer, drier and more variable growing conditions in the temperate to subtropical latitudes towards 2050 and beyond. Short-term (1-5 day) spikes ...

  2. The Effect of Temperature Changes in Vitreoretinal Surgery

    PubMed Central

    Romano, Mario R.; Romano, Vito; Mauro, Alessandro; Angi, Martina; Costagliola, Ciro; Ambrosone, Luigi

    2016-01-01

    Purpose Recent studies on temperature control in biology and medicine have found the temperature as a new instrument in healthcare. In this manuscript, we reviewed the effects of temperature and its potential role in pars plana vitrectomy. We also examined the relationship between intraocular pressure, viscosity, and temperature in order to determine the best balance to manipulate the tamponades during the surgery. Methods A literature review was performed to identify potentially relevant studies on intraocular temperature. Physics equations were applied to explain the described effects of temperature changes on the behavior of the endotamponades commonly used during vitreoretinal surgery. We also generated an operating diagram on the pressure–temperature plane for the values of both vapor–liquid equilibrium and intraocular pressure. Results The rapid circulation of fluid in the vitreous cavity reduces the heat produced by the retinal and choroidal surface, bringing the temperature toward room temperature (22°C, deep hypothermia). Temperature increases with endolaser treatment, air infusion, and the presence of silicone oil. The variations in temperature during vitreoretinal surgery are clinically significant, as the rheology of tamponades can be better manipulated by modulating intraocular pressure and temperature. Conclusions During vitreoretinal surgery, the intraocular temperature showed rapid and significant fluctuations at different steps of the surgical procedure inside the vitreous cavity. Temperature control can modulate the rheology of tamponades. Translational Relevance Intraoperative temperature control can improve neuroprotection during vitreoretinal surgery, induce the vaporization of perfluorcarbon liquid, and change the shear viscosity of silicone oil. PMID:26929884

  3. Correlation of hippocampal theta rhythm with changes in cutaneous temperature

    NASA Technical Reports Server (NTRS)

    Horowitz, J. M.; Saleh, M. A.; Karem, R. D.

    1974-01-01

    Investigation of the possibility that the hippocampus performs the function of alerting an animal to changes in cutaneous temperature, using unanesthetized, loosely restrained rabbits. The results indicate that the hippocampal theta rhythm, which appears to be evoked by changes in cutaneous temperature, can be related to a specific type of hyppocampal neuron which is, in turn, connected with other areas of the brain involved in temperature regulation.

  4. Stratospheric temperature changes during the satellite era

    NASA Astrophysics Data System (ADS)

    Seidel, Dian J.; Li, Jian; Mears, Carl; Moradi, Isaac; Nash, John; Randel, William J.; Saunders, Roger; Thompson, David W. J.; Zou, Cheng-Zhi

    2016-01-01

    Satellite-based layer average stratospheric temperature (T) climate data records (CDRs) now span more than three decades and so can elucidate climate variability associated with processes on multiple time scales. We intercompare and analyze available published T CDRs covering at least two decades, with a focus on Stratospheric Sounding Unit (SSU) and Microwave Sounding Unit (MSU) CDRs. Recent research has reduced but not eliminated discrepancies between SSU CDRs developed by NOAA and the UK Meteorological Office. The MSU CDRs from NOAA and Remote Sensing Systems are in closer agreement than the CDR from the University of Alabama in Huntsville. The latter has a previously unreported inhomogeneity in 2005, revealed by an abrupt increase in the magnitude and spatial variability of T anomaly differences between CDRs. Although time-varying biases remain in both SSU and MSU CDRs, multiple linear regression analyses reveal consistent solar, El Niño-Southern Oscillation (ENSO), quasi-biennial oscillation, aerosol, and piecewise-linear trend signals. Together, these predictors explain 80 to 90% of the variance in the near-global-average T CDRs. The most important predictor variables (in terms of percent explained variance in near-global-average T) for lower stratospheric T measured by MSU are aerosols, solar variability, and ENSO. Trends explain the largest percentage of variance in observations from all three SSU channels. In MSU and SSU CDRs, piecewise-linear trends, with a 1995 break point, indicate cooling during 1979-1994 but no trend during 1995-2013 for MSU and during 1995-2005 for SSU. These observational findings provide a basis for evaluating climate model simulations of stratospheric temperature during the past 35 years.

  5. Temperature variation makes ectotherms more sensitive to climate change.

    PubMed

    Paaijmans, Krijn P; Heinig, Rebecca L; Seliga, Rebecca A; Blanford, Justine I; Blanford, Simon; Murdock, Courtney C; Thomas, Matthew B

    2013-08-01

    Ectotherms are considered to be particularly vulnerable to climate warming. Descriptions of habitat temperatures and predicted changes in climate usually consider mean monthly, seasonal or annual conditions. Ectotherms, however, do not simply experience mean conditions, but are exposed to daily fluctuations in habitat temperatures. Here, we highlight how temperature fluctuation can generate 'realized' thermal reaction (fitness) norms that differ from the 'fundamental' norms derived under standard constant temperatures. Using a mosquito as a model organism, we find that temperature fluctuation reduces rate processes such as development under warm conditions, increases processes under cool conditions, and reduces both the optimum and the critical maximum temperature. Generalizing these effects for a range of terrestrial insects reveals that prevailing daily fluctuations in temperature should alter the sensitivity of species to climate warming by reducing 'thermal safety margins'. Such effects of daily temperature dynamics have generally been ignored in the climate change literature. PMID:23630036

  6. Temperature variation makes ectotherms more sensitive to climate change

    PubMed Central

    Paaijmans, Krijn P; Heinig, Rebecca L; Seliga, Rebecca A; Blanford, Justine I; Blanford, Simon; Murdock, Courtney C; Thomas, Matthew B

    2013-01-01

    Ectotherms are considered to be particularly vulnerable to climate warming. Descriptions of habitat temperatures and predicted changes in climate usually consider mean monthly, seasonal or annual conditions. Ectotherms, however, do not simply experience mean conditions, but are exposed to daily fluctuations in habitat temperatures. Here, we highlight how temperature fluctuation can generate ‘realized’ thermal reaction (fitness) norms that differ from the ‘fundamental’ norms derived under standard constant temperatures. Using a mosquito as a model organism, we find that temperature fluctuation reduces rate processes such as development under warm conditions, increases processes under cool conditions, and reduces both the optimum and the critical maximum temperature. Generalizing these effects for a range of terrestrial insects reveals that prevailing daily fluctuations in temperature should alter the sensitivity of species to climate warming by reducing ‘thermal safety margins’. Such effects of daily temperature dynamics have generally been ignored in the climate change literature. PMID:23630036

  7. Seasonal mean temperature changes control future heat waves

    NASA Astrophysics Data System (ADS)

    Argüeso, Daniel; Di Luca, Alejandro; Perkins-Kirkpatrick, Sarah E.; Evans, Jason P.

    2016-07-01

    Increased temperature will result in longer, more frequent, and more intense heat waves. Changes in temperature variability have been deemed necessary to account for future heat wave characteristics. However, this has been quantified only in Europe and North America, while the rest of the globe remains unexplored. Using late century global climate projections, we show that annual mean temperature increases is the key factor defining heat wave changes in most regions. We find that commonly studied areas are an exception rather than the standard and the mean climate change signal generally outweighs any influence from variability changes. More importantly, differences in warming across seasons are responsible for most of the heat wave changes and their consideration relegates the contribution of variability to a marginal role. This reveals that accurately capturing mean seasonal changes is crucial to estimate future heat waves and reframes our interpretation of future temperature extremes.

  8. Modeling Climate Change Effects on Stream Temperatures in Regulated Rivers

    NASA Astrophysics Data System (ADS)

    Null, S. E.; Akhbari, M.; Ligare, S. T.; Rheinheimer, D. E.; Peek, R.; Yarnell, S. M.; Viers, J. H.

    2013-12-01

    We provide a method for examining mesoscale stream temperature objectives downstream of dams with anticipated climate change using an integrated multi-model approach. Changing hydroclimatic conditions will likely impact stream temperatures within reservoirs and below dams, and affect downstream ecology. We model hydrology and water temperature using a series of linked models that includes a hydrology model to predict natural unimpaired flows in upstream reaches, a reservoir temperature simulation model , an operations model to simulate reservoir releases, and a stream temperature simulation model to simulate downstream conditions . All models are 1-dimensional and operate on either a weekly or daily timestep. First, we model reservoir thermal dynamics and release operations of hypothetical reservoirs of different sizes, elevations, and latitudes with climate-forced inflow hydrologies to examine the potential to manage stream temperatures for coldwater habitat. Results are presented as stream temperature change from the historical time period and indicate that reservoir releases are cooler than upstream conditions, although the absolute temperatures of reaches below dams warm with climate change. We also apply our method to a case study in California's Yuba River watershed to evaluate water regulation and hydropower operation effects on stream temperatures with climate change. Catchments of the upper Yuba River are highly-engineered, with multiple, interconnected infrastructure to provide hydropower, water supply, flood control, environmental flows, and recreation. Results illustrate climate-driven versus operations-driven changes to stream temperatures. This work highlights the need for methods to consider reservoir regulation effects on stream temperatures with climate change, particularly for hydropower relicensing (which currently ignores climate change) such that impacts to other beneficial uses like coldwater habitat and instream ecosystems can be

  9. Phase change based cooling for high burst mode heat loads with temperature regulation above the phase change temperature

    SciTech Connect

    The United States of America as represented by the United States Department of Energy

    2009-12-15

    An apparatus and method for transferring thermal energy from a heat load is disclosed. In particular, use of a phase change material and specific flow designs enables cooling with temperature regulation well above the fusion temperature of the phase change material for medium and high heat loads from devices operated intermittently (in burst mode). Exemplary heat loads include burst mode lasers and laser diodes, flight avionics, and high power space instruments. Thermal energy is transferred from the heat load to liquid phase change material from a phase change material reservoir. The liquid phase change material is split into two flows. Thermal energy is transferred from the first flow via a phase change material heat sink. The second flow bypasses the phase change material heat sink and joins with liquid phase change material exiting from the phase change material heat sink. The combined liquid phase change material is returned to the liquid phase change material reservoir. The ratio of bypass flow to flow into the phase change material heat sink can be varied to adjust the temperature of the liquid phase change material returned to the liquid phase change material reservoir. Varying the flowrate and temperature of the liquid phase change material presented to the heat load determines the magnitude of thermal energy transferred from the heat load.

  10. Influence of temperature changes on migraine occurrence in Germany

    NASA Astrophysics Data System (ADS)

    Scheidt, Jörg; Koppe, Christina; Rill, Sven; Reinel, Dirk; Wogenstein, Florian; Drescher, Johannes

    2013-07-01

    Many factors trigger migraine attacks. Weather is often reported to be one of the most common migraine triggers. However, there is little scientific evidence about the underlying mechanisms and causes. In our pilot study, we used smartphone apps and a web form to collect around 4,700 migraine messages in Germany between June 2011 and February 2012. Taking interdiurnal temperature changes as an indicator for changes in the prevailing meteorological conditions, our analyses were focused on the relationship between temperature changes and the frequency of occurrence of migraine attacks. Linear trends were fitted to the total number of migraine messages with respect to temperature changes. Statistical and systematic errors were estimated. Both increases and decreases in temperature lead to a significant increase in the number of migraine messages. A temperature increase (decrease) of 5 °C resulted in an increase of 19 ± 7 % (24 ± 8 %) in the number of migraine messages.

  11. Influence of temperature changes on migraine occurrence in Germany.

    PubMed

    Scheidt, Jörg; Koppe, Christina; Rill, Sven; Reinel, Dirk; Wogenstein, Florian; Drescher, Johannes

    2013-07-01

    Many factors trigger migraine attacks. Weather is often reported to be one of the most common migraine triggers. However, there is little scientific evidence about the underlying mechanisms and causes. In our pilot study, we used smartphone apps and a web form to collect around 4,700 migraine messages in Germany between June 2011 and February 2012. Taking interdiurnal temperature changes as an indicator for changes in the prevailing meteorological conditions, our analyses were focused on the relationship between temperature changes and the frequency of occurrence of migraine attacks. Linear trends were fitted to the total number of migraine messages with respect to temperature changes. Statistical and systematic errors were estimated. Both increases and decreases in temperature lead to a significant increase in the number of migraine messages. A temperature increase (decrease) of 5 °C resulted in an increase of 19 ± 7 % (24 ± 8 %) in the number of migraine messages. PMID:22895651

  12. Photovoltage response to temperature change at oxide semiconductor electrodes

    NASA Technical Reports Server (NTRS)

    Reichman, B.; Byvik, C. E.

    1981-01-01

    A study has been carried out on single crystal electrodes of TiO2, SrTiO3, and alpha-Fe2O3 and polycrystalline WO3 to investigate the effect of cell temperature on the onset potential of n-type oxide semiconductor electrodes. It is found that the change of the onset potential with temperature is due to the potential change across the Helmholtz layer. The amount of this change depends on the point of zero zeta potential (pzzp) of the semiconductor electrode. The possibility of increasing the solar-to-chemical energy conversion efficiency of a photochemical cell by increasing the cell temperature is discussed.

  13. Observation of temperature trace, induced by changing of temperature inside the human body, on the human body skin using commercially available IR camera

    NASA Astrophysics Data System (ADS)

    Trofimov, Vyacheslav A.; Trofimov, Vladislav V.

    2015-05-01

    As it is well-known, application of the passive THz camera for the security problems is very promising way. It allows seeing concealed object without contact with a person and this camera is non-dangerous for a person. In previous papers, we demonstrate new possibility of the passive THz camera using for a temperature difference observing on the human skin if this difference is caused by different temperatures inside the body. For proof of validity of our statement we make the similar physical experiment using the IR camera. We show a possibility of temperature trace on human body skin, caused by changing of temperature inside the human body due to water drinking. We use as a computer code that is available for treatment of images captured by commercially available IR camera, manufactured by Flir Corp., as well as our developed computer code for computer processing of these images. Using both codes we demonstrate clearly changing of human body skin temperature induced by water drinking. Shown phenomena are very important for the detection of forbidden samples and substances concealed inside the human body using non-destructive control without X-rays using. Early we have demonstrated such possibility using THz radiation. Carried out experiments can be used for counter-terrorism problem solving. We developed original filters for computer processing of images captured by IR cameras. Their applications for computer processing of images results in a temperature resolution enhancing of cameras.

  14. Compensating temperature-induced ultrasonic phase and amplitude changes

    NASA Astrophysics Data System (ADS)

    Gong, Peng; Hay, Thomas R.; Greve, David W.; Junker, Warren R.; Oppenheim, Irving J.

    2016-04-01

    In ultrasonic structural health monitoring (SHM), environmental and operational conditions, especially temperature, can significantly affect the propagation of ultrasonic waves and thus degrade damage detection. Typically, temperature effects are compensated using optimal baseline selection (OBS) or optimal signal stretch (OSS). The OSS method achieves compensation by adjusting phase shifts caused by temperature, but it does not fully compensate phase shifts and it does not compensate for accompanying signal amplitude changes. In this paper, we develop a new temperature compensation strategy to address both phase shifts and amplitude changes. In this strategy, OSS is first used to compensate some of the phase shifts and to quantify the temperature effects by stretching factors. Based on stretching factors, empirical adjusting factors for a damage indicator are then applied to compensate for the temperature induced remaining phase shifts and amplitude changes. The empirical adjusting factors can be trained from baseline data with temperature variations in the absence of incremental damage. We applied this temperature compensation approach to detect volume loss in a thick wall aluminum tube with multiple damage levels and temperature variations. Our specimen is a thick-walled short tube, with dimensions closely comparable to the outlet region of a frac iron elbow where flow-induced erosion produces the volume loss that governs the service life of that component, and our experimental sequence simulates the erosion process by removing material in small damage steps. Our results show that damage detection is greatly improved when this new temperature compensation strategy, termed modified-OSS, is implemented.

  15. Is Brain Emulation Dangerous?

    NASA Astrophysics Data System (ADS)

    Eckersley, Peter; Sandberg, Anders

    2013-12-01

    Brain emulation is a hypothetical but extremely transformative technology which has a non-zero chance of appearing during the next century. This paper investigates whether such a technology would also have any predictable characteristics that give it a chance of being catastrophically dangerous, and whether there are any policy levers which might be used to make it safer. We conclude that the riskiness of brain emulation probably depends on the order of the preceding research trajectory. Broadly speaking, it appears safer for brain emulation to happen sooner, because slower CPUs would make the technology`s impact more gradual. It may also be safer if brains are scanned before they are fully understood from a neuroscience perspective, thereby increasing the initial population of emulations, although this prediction is weaker and more scenario-dependent. The risks posed by brain emulation also seem strongly connected to questions about the balance of power between attackers and defenders in computer security contests. If economic property rights in CPU cycles1 are essentially enforceable, emulation appears to be comparatively safe; if CPU cycles are ultimately easy to steal, the appearance of brain emulation is more likely to be a destabilizing development for human geopolitics. Furthermore, if the computers used to run emulations can be kept secure, then it appears that making brain emulation technologies ―open‖ would make them safer. If, however, computer insecurity is deep and unavoidable, openness may actually be more dangerous. We point to some arguments that suggest the former may be true, tentatively implying that it would be good policy to work towards brain emulation using open scientific methodology and free/open source software codebases

  16. The Trends of Soil Temperature Change Associated with Air Temperature Change in Korea from 1973 to 2012

    NASA Astrophysics Data System (ADS)

    Lee, Bo-Hyun; Park, Byeong-Hak; Koh, Eun-Hee; Lee, Kang-Kun

    2015-04-01

    Examining long-term trends of the soil temperature can contribute to assessing subsurface thermal environment. The recent 40-year (1973-2012) meteorological data from 14 Korea Meteorological Administration (KMA) stations was analyzed in this study to estimate the temporal variations of air and soil temperatures (at depths 0.5 and 1.0m) in Korea and their relations. The information on regional characteristics of study sites was also collected to investigate the local and regional features influencing the soil temperature. The long-term increasing trends of both air and soil temperatures were estimated by using simple linear regression analysis. The air temperature rise and soil temperature rise were compared for every site to reveal the relation between air and soil temperature changes. In most sites, the proportion of soil temperature rise to air temperature rise was nearly one to one except a few sites. The difference between the air and soil temperature trends at those sites may be attributed to the combined effect of soil properties such as thermal diffusivity and soil moisture content. The impact of urbanization on the air and soil temperature was also investigated in this study. Establishment of the relationship between the air and soil temperatures can help predicting the soil temperature change in a region where no soil temperature data is obtained by using air temperature data. For rigorous establishment of the relationship between soil and air temperatures, more thorough investigation on the soil thermal properties is necessary through additional monitoring and accompanied validation of the proposed relations. Keywords : Soil temperature, Air temperature, Cross-correlation analysis, Soil thermal diffusivity, Urbanization effect Acknowledgement This work was supported by the research project of "Advanced Technology for Groundwater Development and Application in Riversides (Geowater+)" in "Water Resources Management Program (code 11 Technology Innovation C05

  17. Climate change signal analysis for Northeast Asian surface temperature

    NASA Astrophysics Data System (ADS)

    Lee, Jeong-Hyeong; Kim, Byungsoo; Sohn, Keon-Tae; Kown, Won-Tae; Min, Seung-Ki

    2005-03-01

    Climate change detection, attribution, and prediction were studied for the surface temperature in the Northeast Asian region using NCEP/NCAR reanalysis data and three coupled-model simulations from ECHAM4/OPYC3, HadCM3, and CCCma GCMs (Canadian Centre for Climate Modeling and Analysis general circulation model). The Bayesian fingerprint approach was used to perform the detection and attribution test for the anthropogenic climate change signal associated with changes in anthropogenic carbon dioxide (CO2) and sulfate aerosol (SO{4/2-}) concentrations for the Northeast Asian temperature. It was shown that there was a weak anthropogenic climate change signal in the Northeast Asian temperature change. The relative contribution of CO2 and SO{4/2-} effects to total temperature change in Northeast Asia was quantified from ECHAM4/OPYC3 and CCCma GCM simulations using analysis of variance. For the observed temperature change for the period of 1959 1998, the CO2 effect contributed 10% 21% of the total variance and the direct cooling effect of SO{4/2-} played a less important role (0% 7%) than the CO2 effect. The prediction of surface temperature change was estimated from the second CO2+SO{4/2-} scenario run of ECHAM4/OPYC3 which has the least error in the simulation of the present-day temperature field near the Korean Peninsula. The result shows that the area-mean surface temperature near the Korean Peninsula will increase by about 1.1° by the 2040s relative to the 1990s.

  18. The Climate Policy Narrative for a Dangerously Warming World

    SciTech Connect

    Sanford, Todd; Frumhoff, Peter; Luers, Amy; Gulledge, Jay

    2014-01-01

    It is time to acknowledge that global average temperatures will likely rise above the 2 C policy target and consider how that deeply troubling prospect should affect priorities for communicating and managing the risks of a dangerously warming climate.

  19. Behavioral responses of Atlantic cod to sea temperature changes

    PubMed Central

    Freitas, Carla; Olsen, Esben Moland; Moland, Even; Ciannelli, Lorenzo; Knutsen, Halvor

    2015-01-01

    Understanding responses of marine species to temperature variability is essential to predict impacts of future climate change in the oceans. Most ectotherms are expected to adjust their behavior to avoid extreme temperatures and minimize acute changes in body temperature. However, measuring such behavioral plasticity in the wild is challenging. Combining 4 years of telemetry-derived behavioral data on juvenile and adult (30–80 cm) Atlantic cod (Gadus morhua), and in situ ocean temperature measurements, we found a significant effect of sea temperature on cod depth use and activity level in coastal Skagerrak. During summer, cod were found in deeper waters when sea surface temperature increased. Further, this effect of temperature was stronger on larger cod. Diel vertical migration, which consists in a nighttime rise to shallow feeding habitats, was stronger among smaller cod. As surface temperature increased beyond ∼15°C, their vertical migration was limited to deeper waters. In addition to larger diel vertical migrations, smaller cod were more active and travelled larger distances compared to larger specimens. Cold temperatures during winter tended, however, to reduce the magnitude of diel vertical migrations, as well as the activity level and distance moved by those smaller individuals. Our findings suggest that future and ongoing rises in sea surface temperature may increasingly deprive cod in this region from shallow feeding areas during summer, which may be detrimental for local populations of the species. PMID:26045957

  20. Phase Change Material Systems for High Temperature Heat Storage.

    PubMed

    Perraudin, David Y S; Binder, Selmar R; Rezaei, Ehsan; Ortonaa, Alberto; Haussener, Sophia

    2015-01-01

    Efficient, cost effective, and stable high-temperature heat storage material systems are important in applications such as high-temperature industrial processes (metal processing, cement and glass manufacturing, etc.), or electricity storage using advanced adiabatic compressed air energy storage. Incorporating phase change media into heat storage systems provides an advantage of storing and releasing heat at nearly constant temperature, allowing steady and optimized operation of the downstream processes. The choice of, and compatibility of materials and encapsulation for the phase change section is crucial, as these must guarantee good and stable performance and long lifetime at low cost. Detailed knowledge of the material properties and stability, and the coupled heat transfer, phase change, and fluid flow are required to allow for performance and lifetime predictions. We present coupled experimental-numerical techniques allowing prediction of the long-term performance of a phase change material-based high-temperature heat storage system. The experimental investigations focus on determination of material properties (melting temperature, heat of fusion, etc.) and phase change material and encapsulation interaction (stability, interface reactions, etc.). The computational investigations focus on an understanding of the multi-mode heat transfer, fluid flow, and phase change processes in order to design the material system for enhanced performance. The importance of both the experimental and numerical approaches is highlighted and we give an example of how both approaches can be complementarily used for the investigation of long-term performance. PMID:26842330

  1. Snow and the ground temperature record of climate change

    NASA Astrophysics Data System (ADS)

    Bartlett, Marshall G.; Chapman, David S.; Harris, Robert N.

    2004-12-01

    Borehole temperature-depth profiles contain a record of surface ground temperature (SGT) changes with time and complement surface air temperature (SAT) analysis to infer climate change over multiple centuries. Ground temperatures are generally warmer than air temperatures due to solar radiation effects in the summer and the insulating effect of snow cover during the winter. The low thermal diffusivity of snow damps surface temperature variations; snow effectively acts as an insulator of the ground during the coldest part of the year. A numerical model of snow-ground thermal interactions is developed to investigate the effect of seasonal snow cover on annual ground temperatures. The model is parameterized in terms of three snow event parameters: onset time of the annual snow event, duration of the event, and depth of snow during the event. These parameters are commonly available from meteorological and remotely sensed data making the model broadly applicable. The model is validated using SAT, subsurface temperature from a depth of 10 cm, and snow depth data from the 6 years of observations at Emigrant Pass climate observatory in northwestern Utah and 217 station years of National Weather Service data from sites across North America. Measured subsurface temperature-time series are compared to changes predicted by the model. The model consistently predicts ground temperature changes that compare well with those observed. Sensitivity analysis of the model leads to a nonlinear relationship between the three snow event parameters (onset, duration, and depth of the annual snow event) and the influence snow has on mean annual SGT.

  2. Dangers of limited SDI

    SciTech Connect

    Marsh, G.E.

    1987-03-01

    Recent efforts to redefine the Strategic Defense Initiative (SDI) are mostly aimed at building support for a system to defend US land-based missiles. This is thought to be a more feasible goal than President Reagan's dream of an impregnable shield to defend the US population against ballistic missiles. But a feasible idea is not necessarily a good one. While chasing the population-defense fantasy would destroy the existing arms control regime and waste the national treasure of money and talent, defending land-based missiles would be dangerous and destabilizing. Defense Secretary Caspar Weinberger held fast to the idea of population defense in January, when he told the Senate Armed Services Committee that even early deployments of SDI systems that could be developed in the near future should be the first phase of a system that would protect the continent. But such statements may reflect the administration's determination to do away with the 1972 Anti-Ballistic Missile Treaty more than its belief that population defense is a reasonable goal. The author notes that, to those longstanding problems of defense decision making, they must now add the pressures of SDI. Furthermore, whatever the motives of those who advocate redirecting SDI, it is clear that concerns about the vulnerability of land-based missiles could be addressed in more sensible ways. 5 references.

  3. Historical changes in air temperature are evident in temperature fluxes measured in the sub-soil.

    NASA Astrophysics Data System (ADS)

    Fraser, Fiona; McCormick, Benjamin; Hallett, Paul; Wookey, Philip; Hopkins, David

    2013-04-01

    Warming trends in soil temperature have implications for a plethora of soil processes, including exacerbated climate change through the net release of greenhouse gases. Whereas long-term datasets of air temperature changes are abundant, a search of scientific literature reveals a lack of information on soil temperature changes and their specific consequences. We analysed five long-term data series collected in the UK (Dundee and Armagh) and Canada (Charlottetown, Ottawa and Swift Current). They show that the temperatures of soils at 5 - 20 cm depth, and sub-soils at 30 - 150 cm depth, increased in line with air temperature changes over the period 1958 - 2003. Differences were found, however, between soil and air temperatures when data were sub-divided into seasons. In spring, soil temperature warming ranged from 0.19°C at 30 cm in Armagh to 4.30°C at 50 cm in Charlottetown. In summer, however, the difference was smaller and ranged from 0.21°C at 10 cm in Ottawa to 3.70°C at 50 cm in Charlottetown. Winter temperatures were warmer in soil and ranged from 0.45°C at 5 cm in Charlottetown to 3.76°C at 150 cm in Charlottetown. There were significant trends in changes to soil temperature over time, whereas air temperature trends tended only to be significant in winter (changes range from 1.27°C in Armagh to 3.35°C in Swift Current). Differences in the seasonal warming patterns between air and soil temperatures have potential implications for the parameterization of models of biogeochemical cycling.

  4. Changes in precipitation and temperature in Xiangjiang River Basin, China

    NASA Astrophysics Data System (ADS)

    Ma, Chong; Pan, Suli; Wang, Guoqing; Liao, Yufang; Xu, Yue-Ping

    2016-02-01

    Global warming brings a huge challenge to society and human being. Understanding historic and future potential climate change will be beneficial to regional crop, forest, and water management. This study aims to analyze the precipitation and temperature changes in the historic period and future period 2021-2050 in the Xiangjiang River Basin, China. The Mann-Kendall rank test for trend and change point analysis was used to analyze the changes in trend and magnitude based on historic precipitation and temperature time series. Four global climate models (GCMs) and a statistical downscaling approach, LARS-WG, were used to estimate future precipitation and temperature under RCP4.5. The results show that annual precipitation in the basin is increasing, although not significant, and will probably continue to increase in the future on the basis of ensemble projections of four GCMs. Temperature is increasing in a significant way and all GCMs projected continuous temperature increase in the future. There will be more extreme events in the future, including both extreme precipitation and temperature.

  5. Mitigating Climate Change with Ocean Pipes: Influencing Land Temperature and Hydrology and Termination Overshoot Risk

    NASA Astrophysics Data System (ADS)

    Kwiatkowski, L.; Caldeira, K.; Ricke, K.

    2014-12-01

    With increasing risk of dangerous climate change geoengineering solutions to Earth's climate problems have attracted much attention. One proposed geoengineering approach considers the use of ocean pipes as a means to increase ocean carbon uptake and the storage of thermal energy in the deep ocean. We use a latest generation Earth System Model (ESM) to perform simulations of idealised extreme implementations of ocean pipes. In our simulations, downward transport of thermal energy by ocean pipes strongly cools the near surface atmosphere - by up to 11°C on a global mean. The ocean pipes cause net thermal energy to be transported from the terrestrial environment to the deep ocean while increasing the global net transport of water to land. By cooling the ocean surface more than the land, ocean pipes tend to promote a monsoonal-type circulation, resulting in increased water vapour transport to land. Throughout their implementation, ocean pipes prevent energy from escaping to space, increasing the amount of energy stored in Earth's climate system despite reductions in surface temperature. As a consequence, our results indicate that an abrupt termination of ocean pipes could cause dramatic increases in surface temperatures beyond that which would have been obtained had ocean pipes not been implemented.

  6. Geothermics of Climate Change: Linking Ground and Air Temperature Change Through Repeat Temperature Measurements in Boreholes From Northwest Utah

    NASA Astrophysics Data System (ADS)

    Davis, M. G.; Harris, R. N.; Chapman, D. S.

    2007-12-01

    Temperature-depth profiles measured in boreholes contain important information about the Earth's changing surface temperature and provide a direct method for reconstructing surface temperature variations over the past several centuries. Differences between temperature-depth logs, on annual to decadal timescales, provide an important test of borehole thermometry. Twelve temperature-depth logs at the northwestern Utah Emigrant Pass Observatory (EPO) borehole, GC-1, seven at borehole SI-1 and five at borehole DM-1, were acquired between the years 1978 and 2007. Differences in temperature logs extend to about 100 m. Below 100 m, differences between temperature logs are effectively zero. SAT data from the meteorological station at EPO and nearby Historical Climatology Network stations are used as a forcing function at the Earth's surface and diffused into the subsurface. These transients reproduce observed subsurface temperature variations reasonably well at each borehole. Comparisons between repeated temperature-depth profiles and diffused SAT transients over the same time period offer strong support for using GST histories to complement SAT data and multi-proxy reconstructions in climate change studies.

  7. Change point analysis of mean annual air temperature in Iran

    NASA Astrophysics Data System (ADS)

    Shirvani, A.

    2015-06-01

    The existence of change point in the mean of air temperature is an important indicator of climate change. In this study, Student's t parametric and Mann-Whitney nonparametric Change Point Models (CPMs) were applied to test whether a change point has occurred in the mean of annual Air Temperature Anomalies Time Series (ATATS) of 27 synoptic stations in different regions of Iran for the period 1956-2010. The Likelihood Ratio Test (LRT) was also applied to evaluate the detected change points. The ATATS of all stations except Bandar Anzali and Gorgan stations, which were serially correlated, were transformed to produce an uncorrelated pre-whitened time series as an input file for the CPMs and LRT. Both the Student's t and Mann-Whitney CPMs detected the change point in the ATATS of (a) Tehran Mehrabad, Abadan, Kermanshah, Khoramabad and Yazd in 1992, (b) Mashhad and Tabriz in 1993, (c) Bandar Anzali, Babolsar and Ramsar in 1994, (d) Kerman and Zahedan in 1996 at 5% significance level. The likelihood ratio test shows that the ATATS before and after detected change points in these 12 stations are normally distributed with different means. The Student's t and Mann-Whitney CPMs suggested different change points for individual stations in Bushehr, Bam, Shahroud, and Gorgan. However, the LRT confirmed the change points in these four stations as 1997, 1996, 1993, and 1996, respectively. No change points were detected in the remaining 11 stations.

  8. Associations of Inter- and Intraday Temperature Change With Mortality.

    PubMed

    Vicedo-Cabrera, Ana M; Forsberg, Bertil; Tobias, Aurelio; Zanobetti, Antonella; Schwartz, Joel; Armstrong, Ben; Gasparrini, Antonio

    2016-02-15

    In this study we evaluated the association between temperature variation and mortality and compared it with the contribution due to mean daily temperature in 6 cities with different climates. Quasi-Poisson time series regression models were applied to estimate the associations (relative risk and 95% confidence interval) of mean daily temperature (99th and 1st percentiles, with temperature of minimum mortality as the reference category), interday temperature variation (difference between the mean temperatures of 2 neighboring days) and intraday temperature variation (diurnal temperature range (DTR)) (referred to as median variation) with mortality in 6 cities: London, United Kingdom; Madrid, Spain; Stockholm, Sweden; New York, New York; Miami, Florida; and Houston, Texas (date range, 1985-2010). All cities showed a substantial increase in mortality risk associated with mean daily temperature, with relative risks reaching 1.428 (95% confidence interval (CI): 1.329, 1.533) for heat in Madrid and 1.467 (95% CI: 1.385, 1.555) for cold in London. Inconsistent results for inter-/intraday change were obtained, except for some evidence of protective associations on hot and cold days (relative risk (RR) = 0.977 (95% CI: 0.955, 0.999) and RR = 0.981 (95% CI: 0.971, 0.991), respectively) in Madrid and on cold days in Stockholm (RR = 0.989, 95% CI: 0.980, 0.998). Our results indicate that the association between mortality and temperature variation is generally minimal compared with mean daily temperatures, although further research on intraday changes is needed. PMID:26811244

  9. Changes in exposure temperature lead to changes in pesticide toxicity to earthworms: A preliminary study.

    PubMed

    Velki, Mirna; Ečimović, Sandra

    2015-11-01

    The occurring climate changes will have direct consequences to all ecosystems, including the soil ecosystems. The effects of climate change include, among other, the changes in temperature and greater frequency and intensity of extreme weather conditions. Temperature is an important factor in ecotoxicological investigations since it can act as a stressor and influence the physiological status of organisms, as well as affect the fate and transport of pollutants present in the environment. However, most of so far conducted (eco)toxicological investigations neglected the possible effects of temperature and focused solely on the effects of toxicants on organisms. Considering that temperature can contribute to the toxicity of pollutants, it is of immense importance to investigate whether the change in the exposure temperature will impact the strength of the toxic effects of pollutants present in soil ecosystems. Therefore, in the present study the toxicity of several commonly used pesticides to earthworms was assessed under different exposure temperatures (15, 20 and 25°C). The results showed that changes in exposure temperature lead to changes in susceptibility of earthworms to particular pesticides. Namely, exposures to the same pesticide concentration at different temperatures lead to different toxicity responses. Increase in exposure temperature in most cases caused increase in toxicity, whereas decrease in temperature mostly caused decrease in toxicity. This preliminary study points to need for an in-depth investigation of mechanisms by which temperature affects the toxicity of pesticides and also provides important data for future research on the effects of temperature change on the soil ecosystems. PMID:26436694

  10. Cryosurgery: ultrastructural changes in pancreas tissue after low temperature exposure.

    PubMed

    Korpan, N N

    2007-04-01

    A number of theoretical and experimental studies, both in vitro and in vivo, have been performed to explain the action of low temperatures on tissue. It is now evident that the thermal parameters used in the past for freezing during cryosurgery were not precise; this may have resulted in the failure of treatment. For the first time, this report describes the early ultrastructural features of pancreatic parenchyma after low temperature exposure, i.e., cryosurgery, in vivo. We demonstrate the effect of freeze-thawing processes using temperatures of various intensities. The cryosurgical response of pancreas parenchyma, i.e., ultrastructural cellular changes in pancreas tissue, was investigated. The electronic microscopic analysis showed that, after local cryodestruction at temperatures of -80 degrees C and -180 degrees C, similar processes occurred within the pancreas tissue in the early postcryosurgical phase -- immediately and up to 24 hours after low temperature exposure on tissue. The exocrine pancreatic cells in the center of the cryozone changed upon thawing. Ultrastructural changes in the exocrine pancreatic cells, where the first signs of dystrophic processes had been noticed, were increased. These ultrastructural changes in the pancreatic cells provide a platform to better understand the mechanisms of damage and the pathogenesis of frostbite after cryosurgery. The properties of the pancreas parenchyma response after low temperature exposure provide important insights into the mechanisms of damage and the cryogenic lesion immediately after thawing in cryosurgery. Our new insights prove on the cell level that suddenly and progressively damaged pancreatic cells in the postcryosurgical zone lead to aseptic cryonecrosis and then to aseptic cryoapoptosis of vital normal tissue. The vascular capillary changes and circulatory stagnation demonstrate the anti-angiogenesis mechanism, which, together with cryoaponecrosis and cryoapoptosis, are some of the main mechanisms

  11. Rearing Temperature Influences Adult Response to Changes in Mating Status.

    PubMed

    Westerman, Erica; Monteiro, Antónia

    2016-01-01

    Rearing environment can have an impact on adult behavior, but it is less clear how rearing environment influences adult behavior plasticity. Here we explore the effect of rearing temperature on adult mating behavior plasticity in the butterfly Bicyclus anynana, a species that has evolved two seasonal forms in response to seasonal changes in temperature. These seasonal forms differ in both morphology and behavior. Females are the choosy sex in cohorts reared at warm temperatures (WS butterflies), and males are the choosy sex in cohorts reared at cooler temperatures (DS butterflies). Rearing temperature also influences mating benefits and costs. In DS butterflies, mated females live longer than virgin females, and mated males live shorter than virgin males. No such benefits or costs to mating are present in WS butterflies. Given that choosiness and mating costs are rearing temperature dependent in B. anynana, we hypothesized that temperature may also impact male and female incentives to remate in the event that benefits and costs of second matings are similar to those of first matings. We first examined whether lifespan was affected by number of matings. We found that two matings did not significantly increase lifespan for either WS or DS butterflies relative to single matings. However, both sexes of WS but not DS butterflies experienced decreased longevity when mated to a non-virgin relative to a virgin. We next observed pairs of WS and DS butterflies and documented changes in mating behavior in response to changes in the mating status of their partner. WS but not DS butterflies changed their mating behavior in response to the mating status of their partner. These results suggest that rearing temperature influences adult mating behavior plasticity in B. anynana. This developmentally controlled behavioral plasticity may be adaptive, as lifespan depends on the partner's mating status in one seasonal form, but not in the other. PMID:26863319

  12. Rearing Temperature Influences Adult Response to Changes in Mating Status

    PubMed Central

    Westerman, Erica; Monteiro, Antónia

    2016-01-01

    Rearing environment can have an impact on adult behavior, but it is less clear how rearing environment influences adult behavior plasticity. Here we explore the effect of rearing temperature on adult mating behavior plasticity in the butterfly Bicyclus anynana, a species that has evolved two seasonal forms in response to seasonal changes in temperature. These seasonal forms differ in both morphology and behavior. Females are the choosy sex in cohorts reared at warm temperatures (WS butterflies), and males are the choosy sex in cohorts reared at cooler temperatures (DS butterflies). Rearing temperature also influences mating benefits and costs. In DS butterflies, mated females live longer than virgin females, and mated males live shorter than virgin males. No such benefits or costs to mating are present in WS butterflies. Given that choosiness and mating costs are rearing temperature dependent in B. anynana, we hypothesized that temperature may also impact male and female incentives to remate in the event that benefits and costs of second matings are similar to those of first matings. We first examined whether lifespan was affected by number of matings. We found that two matings did not significantly increase lifespan for either WS or DS butterflies relative to single matings. However, both sexes of WS but not DS butterflies experienced decreased longevity when mated to a non-virgin relative to a virgin. We next observed pairs of WS and DS butterflies and documented changes in mating behavior in response to changes in the mating status of their partner. WS but not DS butterflies changed their mating behavior in response to the mating status of their partner. These results suggest that rearing temperature influences adult mating behavior plasticity in B. anynana. This developmentally controlled behavioral plasticity may be adaptive, as lifespan depends on the partner’s mating status in one seasonal form, but not in the other. PMID:26863319

  13. Laser-tissue photothermal interaction and tissue temperature change

    NASA Astrophysics Data System (ADS)

    Ives, Andrea K.; Chen, Wei R.; Jassemnejad, Baha; Bartels, Kenneth E.; Liu, Hong; Nordquist, John A.; Nordquist, Robert E.

    2000-06-01

    Responses of tissue to laser stimulation are crucial in both disease diagnostics and treatment. In general, when tissue absorbs laser energy photothermal interaction occurs. The most important signature of the photothermal reaction is the tissue temperature change during and after the laser irradiation. Experimentally, the tissue reaction to laser irradiation can be measured by numerous methods including direct temperature measurement and measurement of perfusion change. In this study, a multiple-channel temperature probe was used to measure tissue temperature change during irradiation of lasers with different wavelengths at different power settings. Tissue temperature in chicken breast tissue as well as skin and breast tumor of rats was measured during irradiation of an 805-nm diode laser. The vertical profiles of temperature were obtained using simultaneous measurement at several different locations. The absorption of laser energy by tissue was enhanced by injecting laser-absorbing dye into the tissue. A Nd:YAG laser of 1064-nm wavelength was also used to irradiate turkey breast tissue. Our results showed that both laser penetration ability and photothermal reaction depended on the wavelength of lasers. In the case of 805-nm laser, the temperature increased rapidly only in the region close to the laser source and the thermal equilibrium could be reached within a short time period. The laser absorbing dye drastically enhanced the thermal reaction, resulting in approximately 4-fold temperature increase. On the contrary, the laser beam with 1064-nm wavelength penetrated deeply into tissue and the tissue temperature continued increasing even after a 10-minute laser irradiation.

  14. Exploring Terrestrial Temperature Changes during the Early Eocene Hyperthermals

    NASA Astrophysics Data System (ADS)

    Snell, K. E.; Clyde, W. C.; Fricke, H. C.; Eiler, J. M.

    2012-12-01

    The Early Eocene is marked by a number of rapid global warming events called hyperthermals. These hyperthermals are associated with negative carbon isotope excursions (CIE) in both marine and terrestrial records. Multiple theories exist to explain the connection of these hyperthermals with the CIEs and each theory predicts different responses by the climate system. Characterizing the timing, duration and magnitude of temperature change that is associated with these hyperthermals is important for determining whether the hyperthermals are all driven by the same underlying climate dynamics or perhaps differ from one another in cause and climatic consequences. In the simplest case, all share a common underlying mechanism; this predicts that the associated temperature changes scale in a predictable way with the magnitude of the CIE (and perhaps exhibit other similarities, such as the relative amplitudes of marine and terrestrial temperature change). To our knowledge, however, the only hyperthermal with paleotemperature data from land is the Paleocene-Eocene Thermal Maximum (PETM). Here we present preliminary carbonate clumped isotope paleotemperature estimates for Early Eocene hyperthermal ETM2/H2 from paleosol carbonates from the Bighorn Basin in Wyoming, USA. We compare the results to existing clumped isotope paleotemperature estimates for the PETM in the Bighorn Basin. Temperatures recorded by paleosol carbonates (which likely reflect near-peak summer ground temperatures) prior to each CIE are ~30°C and increase to ~40-43°C during the apex of each CIE. Following both CIEs, temperatures drop back to pre-CIE values. In the case of ETM2/H2, temperatures begin to rise again immediately, possibly in association with a later hyperthermal, though further work needs to be done to establish this with certainty. These preliminary data suggest that both the absolute values and the magnitudes of temperature changes associated with the PETM and ETM2/H2 are similar; the

  15. Global Surface Temperature Change and Uncertainties Since 1861

    NASA Technical Reports Server (NTRS)

    Shen, Samuel S. P.; Lau, William K. M. (Technical Monitor)

    2002-01-01

    The objective of this talk is to analyze the warming trend and its uncertainties of the global and hemi-spheric surface temperatures. By the method of statistical optimal averaging scheme, the land surface air temperature and sea surface temperature observational data are used to compute the spatial average annual mean surface air temperature. The optimal averaging method is derived from the minimization of the mean square error between the true and estimated averages and uses the empirical orthogonal functions. The method can accurately estimate the errors of the spatial average due to observational gaps and random measurement errors. In addition, quantified are three independent uncertainty factors: urbanization, change of the in situ observational practices and sea surface temperature data corrections. Based on these uncertainties, the best linear fit to annual global surface temperature gives an increase of 0.61 +/- 0.16 C between 1861 and 2000. This lecture will also touch the topics on the impact of global change on nature and environment. as well as the latest assessment methods for the attributions of global change.

  16. Summer hot temperature Return Levels in the climate change context

    NASA Astrophysics Data System (ADS)

    Parey, Sylvie; Thu Huong Hoang, Thi

    2015-04-01

    Climate change and the role of human activities are now attested, and IPCC stated in its last assessment report issued in 2013-2014 that "continued emissions of greenhouse gases will cause further warming and changes in all components of the climate system". In such a context, it is now impossible to consider temperature time series as stationary to estimate extreme values like Return Levels (RL) of hot summer temperature. The first approach, used to estimate near future RLs, consists in identifying and extrapolating trends in the parameters of the classical extreme value distributions. For the design of new installations and a farther time scale, a new methodology has been proposed in order to take climate model results into account. This methodology is based on the link between trends in mean and variance and trends in extremes. Climate model results allow inferring far future mean and variance of temperature, which are more robust outputs than the changes in extreme events, and then future extremes can be estimated through the extremes of the stationary residuals obtained when mean and variance trends have been removed and these future mean and variance. Both approaches will be illustrated using an observed temperature time series and different climate models as in Parey et al. 2010. Parey, S., T. T. H. Hoang, and D. Dacunha-Castelle (2010b), Different ways to compute temperature return levels in the climate change context, Environmetrics, 21, 698-718.

  17. Climate change and the impact of extreme temperatures on aviation

    NASA Astrophysics Data System (ADS)

    Coffel, E.; Horton, R.

    2014-12-01

    Weather is the most significant factor affecting aircraft operations, accounting for 70-80% of passenger delays and costing airlines hundreds of millions of dollars per year in lost revenue. Temperature and airport elevation significantly influence the maximum allowable takeoff weight of an aircraft by changing the surface air density and thus the lift produced at a given speed. For a given runway length, airport elevation, and aircraft type there is a temperature threshold above which the airplane cannot take off at its maximum weight and thus must be weight restricted. The number of summer days necessitating weight restriction has increased since 1980 along with the observed increase in surface temperature. Climate change is projected to increase mean temperatures at all airports and significantly increase the frequency and severity of extreme heat events at some. These changes will negatively affect aircraft performance, leading to increased weight restrictions especially at airports with short runways and little room to expand. For a Boeing 737-800 aircraft, we find that the number of weight restriction days between May and September will increase by 50-100% at four major airports in the United States by 2050-2070 under the RCP8.5 high emissions scenario. These performance reductions may have a significant economic effect on the airline industry, leading to lower profits and higher passenger fares. Increased weight restrictions have previously been identified as potential impacts of climate change, but this study is the first to quantify the effect of higher temperatures on commercial aviation.

  18. Scaling law for electrocaloric temperature change in antiferroelectrics

    PubMed Central

    Lisenkov, S.; Mani, B. K.; Glazkova, E.; Miller, C. W.; Ponomareva, I.

    2016-01-01

    A combination of theoretical and first-principles computational methods, along with experimental evidence from the literature, were used to predict the existence of a scaling law for the electrocaloric temperature change in antiferroelectric materials. We show that the temperature change scales quadratically with electric field, allowing a simple transformation to collapse the set of ΔT(E) onto a single curve. This offers a unique method that can be used to predict electrocaloric behavior beyond the limits of present measurement ranges or in regions where data are not yet available. PMID:26796343

  19. Phase change material for temperature control and material storage

    NASA Technical Reports Server (NTRS)

    Wessling, Jr., Francis C. (Inventor); Blackwood, James M. (Inventor)

    2011-01-01

    A phase change material comprising a mixture of water and deuterium oxide is described, wherein the mole fraction of deuterium oxide is selected so that the mixture has a selected phase change temperature within a range between 0.degree. C. and 4.degree. C. The mixture is placed in a container and used for passive storage and transport of biomaterials and other temperature sensitive materials. Gels, nucleating agents, freezing point depression materials and colorants may be added to enhance the characteristics of the mixture.

  20. Thermally chargeable supercapacitor working in a homogeneous, changing temperature field

    NASA Astrophysics Data System (ADS)

    Lim, Hyuck; Shi, Yang; Qiao, Yu

    2016-04-01

    A thermally chargeable supercapacitor (TCS) system is developed to harvest electrical energy from a uniform temperature field of a changing low-grade heat source. Without any temperature gradient, the TCS absorbs heat when temperature rises and releases electricity during discharging. As temperature decreases, the system configuration returns to the initial condition, so that the thermal-to-electrical energy conversion can be continuously conducted. With a nickel-coated carbon nanotube or nanoporous carbon-based electrode, the thermal sensitivity and the electrode surface area are enhanced simultaneously, leading to a high output voltage around 100-160 mV and a high specific energy of 600-1800 mJ per gram of electrode material in each thermal cycle, with a mild temperature range of ~50 °C.

  1. Ambient Temperature Changes and the Impact to Time Measurement Error

    NASA Astrophysics Data System (ADS)

    Ogrizovic, V.; Gucevic, J.; Delcev, S.

    2012-12-01

    Measurements in Geodetic Astronomy are mainly outdoors and performed during a night, when the temperature often decreases very quickly. The time-keeping during a measuring session is provided by collecting UTC time ticks from a GPS receiver and transferring them to a laptop computer. An interrupt handler routine processes received UTC impulses in real-time and calculates the clock parameters. The characteristics of the computer quartz clock are influenced by temperature changes of the environment. We exposed the laptop to different environmental temperature conditions, and calculate the clock parameters for each environmental model. The results show that the laptop used for time-keeping in outdoor measurements should be kept in a stable temperature environment, at temperatures near 20° C.

  2. Global Stream Temperatures and Flows under Climate Change

    NASA Astrophysics Data System (ADS)

    van Vliet, M. T.; Yearsley, J. R.; Franssen, W. H.; Ludwig, F.; Haddeland, I.; Lettenmaier, D. P.; Kabat, P.

    2012-12-01

    Climate change will affect thermal and hydrologic regimes of rivers, having a direct impact on human water use and freshwater ecosystems. Here we assess the impact of climate change on stream temperature and streamflow globally. We used a physically-based stream temperature river basin model (RBM) linked to the Variable Infiltration Capacity (VIC) model. The modelling framework was adapted for global application including impacts of reservoirs and thermal heat discharges, and was validated using observed water temperature and river discharge records in large river basins globally. VIC-RBM was forced with an ensemble of bias-corrected Global Climate Model (GCM) output resulting in global projections of daily streamflow and water temperature for the 21st century. Global mean and high (95th percentile) stream temperatures are projected to increase on average by 0.8-1.6 (1.0-2.2)°C for the SRES B1-A2 scenario for 2071-2100 relative to 1971-2000. The largest water temperature increases are projected for Europe, North America, Southeast Asia, South Africa and parts of Australia. In these regions, the sensitivities for warming are exacerbated by projected decreases in summer low flows. Large increases in water temperature combined with decreases in low flows are found for the southeastern U.S., Europe and eastern China. These regions could potentially be affected by increased deterioration of water quality and freshwater habitats, and reduced water available for beneficial uses such as thermoelectric power production.

  3. Can air temperature be used to project influences of climate change on stream temperature?

    USGS Publications Warehouse

    Arismendi, Ivan; Safeeq, Mohammad; Dunham, Jason B.; Johnson, Sherri L.

    2014-01-01

    Worldwide, lack of data on stream temperature has motivated the use of regression-based statistical models to predict stream temperatures based on more widely available data on air temperatures. Such models have been widely applied to project responses of stream temperatures under climate change, but the performance of these models has not been fully evaluated. To address this knowledge gap, we examined the performance of two widely used linear and nonlinear regression models that predict stream temperatures based on air temperatures. We evaluated model performance and temporal stability of model parameters in a suite of regulated and unregulated streams with 11–44 years of stream temperature data. Although such models may have validity when predicting stream temperatures within the span of time that corresponds to the data used to develop them, model predictions did not transfer well to other time periods. Validation of model predictions of most recent stream temperatures, based on air temperature–stream temperature relationships from previous time periods often showed poor performance when compared with observed stream temperatures. Overall, model predictions were less robust in regulated streams and they frequently failed in detecting the coldest and warmest temperatures within all sites. In many cases, the magnitude of errors in these predictions falls within a range that equals or exceeds the magnitude of future projections of climate-related changes in stream temperatures reported for the region we studied (between 0.5 and 3.0 °C by 2080). The limited ability of regression-based statistical models to accurately project stream temperatures over time likely stems from the fact that underlying processes at play, namely the heat budgets of air and water, are distinctive in each medium and vary among localities and through time.

  4. Temporal changes and variability in temperature series over Peninsular Malaysia

    NASA Astrophysics Data System (ADS)

    Suhaila, Jamaludin

    2015-02-01

    With the current concern over climate change, the descriptions on how temperature series changed over time are very useful. Annual mean temperature has been analyzed for several stations over Peninsular Malaysia. Non-parametric statistical techniques such as Mann-Kendall test and Theil-Sen slope estimation are used primarily for assessing the significance and detection of trends, while a nonparametric Pettitt's test and sequential Mann-Kendall test are adopted to detect any abrupt climate change. Statistically significance increasing trends for annual mean temperature are detected for almost all studied stations with the magnitude of significant trend varied from 0.02°C to 0.05°C per year. The results shows that climate over Peninsular Malaysia is getting warmer than before. In addition, the results of the abrupt changes in temperature using Pettitt's and sequential Mann-Kendall test reveal the beginning of trends which can be related to El Nino episodes that occur in Malaysia. In general, the analysis results can help local stakeholders and water managers to understand the risks and vulnerabilities related to climate change in terms of mean events in the region.

  5. Climate Change Effects on Soil Water and Temperature

    NASA Astrophysics Data System (ADS)

    Seyfried, M. S.; Chandler, D. G.; Marks, D. G.

    2011-12-01

    Soil serves as the critical interface between physical changes in climate and the biological impacts of those changes. While there is general agreement among Global Climate Models concerning the amount and trend of world air temperature change in the upcoming decades, there is less agreement regarding precipitation trends and much less agreement with respect to trends in the "soil climate" (soil water content and temperature). The difficulties with soil are probably related to variable and poorly tested land surface parameterizations. Working at sites spanning a 1000 m elevation gradient in the Reynolds Creek Experimental Watershed (RCEW) in Idaho, we showed that, over a 45 year period, the annual air temperature increased about 2° C. During that time, the amount of precipitation remained constant, but the precipitation phase shifted considerably from snow to rain depending on site elevation. Most predictions for this environment are for drier, warmer soils. We used soil water and temperature data collected at the same sites for the past 30 years in the RCEW to determine if those trends occurred. We found no significant trend in either soil water content or temperature at any site over the 30 year period. The lack of a soil water trend is related to the vegetation dynamics in this semiarid environment, where very low leaf are index values, and very dry soils much of the year, serve to restrict the impact of increased evaporative demand on transpiration. The lack of soil temperature trends is related to interactions with vegetative and snow cover, especially snow cover, which can effectively modulate exceptionally cold air temperatures. In both cases, it is clear that climate change is not directly imprinted on the soil, but affected by interactions with what is growing in, or laying on the soil.

  6. Long-term changes in sea surface temperatures

    SciTech Connect

    Parker, D.E.

    1994-12-31

    Historical observations of sea surface temperature since 1856 have been improved by applying corrections to compensate for the predominant use of uninsulated or partly insulated buckets until the Second World War. There are large gaps in coverage in the late nineteenth century and around the two world wars, but a range of statistical techniques suggest that these gaps do not severely prejudice estimates of global and regional climatic change. Nonetheless, to improve the analysis on smaller scales, many unused historical data are to be digitized and incorporated. For recent years, satellite-based sea surface temperatures have improved the coverage, after adjustments for their biases relative to in situ data. An initial version of a nominally globally complete sea ice and interpolated sea surface temperature data set, beginning in 1871, has been created for use in numerical simulations of recent climate. Long time series of corrected regional, hemispheric, and global sea surface temperatures are mostly consistent with corresponding night marine air temperature series, and confirm the regionally specific climatic changes portrayed in the Scientific Assessments of the intergovernmental Panel on Climate Change. The observations also show an El Nino-like oscillation on bidecadal and longer time scales.

  7. Changes of temperature-related agroclimatic indices in Poland

    NASA Astrophysics Data System (ADS)

    Graczyk, D.; Kundzewicz, Z. W.

    2016-04-01

    The agricultural sector in Poland is of considerable social and economic importance for the nation. Climate variability and change are of primary relevance to this largely climate-dependent sector. Changes in seven temperature-related agroclimatic indices (lengths of the growing season and of the frost-free season, days of occurrence of the last spring frost and of the first autumn frost; and annual sums of growing degree-days for three values of temperature threshold) in Poland in 1951-2010 are examined. As expected, they generally correspond to the overwhelming and ubiquitous warming. Many, but not all, detected trends are statistically significant. However, for some indices, strong natural variability overshadows eventual trends. Projections of temperature-related agroclimatic indices for the future, based on regional climate models, are also discussed.

  8. Near-Term Acceleration In The Rate of Temperature Change

    SciTech Connect

    Smith, Steven J.; Edmonds, James A.; Hartin, Corinne A.; Mundra, Anupriya; Calvin, Katherine V.

    2015-03-09

    Anthropogenically-driven climate changes, which are expected to impact human and natural systems, are often expressed in terms of global-mean temperature . The rate of climate change over multi-decadal scales is also important, with faster rates of change resulting in less time for human and natural systems to adapt . We find that current trends in greenhouse gas and aerosol emissions are now moving the Earth system into a regime in terms of multi-decadal rates of change that are unprecedented for at least the last 1000 years. The rate of global-mean temperature increase in the CMIP5 archive over 40-year periods increases to 0.25±0.05 (1σ) °C per decade by 2020, an average greater than peak rates of change during the previous 1-2 millennia. Regional rates of change in Europe, North America and the Arctic are higher than the global average. Research on the impacts of such near-term rates of change is urgently needed.

  9. Near-term acceleration in the rate of temperature change

    NASA Astrophysics Data System (ADS)

    Smith, Steven J.; Edmonds, James; Hartin, Corinne A.; Mundra, Anupriya; Calvin, Katherine

    2015-04-01

    Anthropogenically driven climate changes, which are expected to impact human and natural systems, are often expressed in terms of global-mean temperature. The rate of climate change over multi-decadal scales is also important, with faster rates of change resulting in less time for human and natural systems to adapt. We find that present trends in greenhouse-gas and aerosol emissions are now moving the Earth system into a regime in terms of multi-decadal rates of change that are unprecedented for at least the past 1,000 years. The rate of global-mean temperature increase in the CMIP5 (ref. ) archive over 40-year periods increases to 0.25 +/- 0.05 °C (1σ) per decade by 2020, an average greater than peak rates of change during the previous one to two millennia. Regional rates of change in Europe, North America and the Arctic are higher than the global average. Research on the impacts of such near-term rates of change is urgently needed.

  10. Pain Measurement through Temperature Changes in Children Undergoing Dental Extractions

    PubMed Central

    Kolosovas-Machuca, Eleazar S.; Martínez-Jiménez, Mario A.; Ramírez-GarcíaLuna, José L.; González, Francisco J.; Campos-Lara, Nadia P.; Pierdant-Perez, Mauricio

    2016-01-01

    Background and Objective. Pain evaluation in children can be a difficult task, since it possesses sensory and affective components that are often hard to discriminate. Infrared thermography has previously been used as a diagnostic tool for pain detection in animals; therefore, the aim of this study was to assess the presence of temperature changes during dental extractions and to evaluate its correlation with heart rate changes as markers of pain and discomfort. Methods. Thermographic changes in the lacrimal caruncle and heart rate measurements were recorded in healthy children scheduled for dental extraction before and during the procedure and compared. Afterwards, correlation between temperature and heart rate was assessed. Results. We found significant differences in temperature and heart rate before the procedure and during the dental extraction (mean difference 4.07°C, p < 0.001, and 18.11 beats per minute, p < 0.001) and no evidence of correlation between both measurements. Conclusion. Thermographic changes in the lacrimal caruncle can be detected in patients who undergo dental extractions. These changes appear to be stable throughout time and to possess very little intersubject variation, thus making them a candidate for a surrogate marker of pain and discomfort. Future studies should be performed to confirm this claim. PMID:27445611

  11. Pain Measurement through Temperature Changes in Children Undergoing Dental Extractions.

    PubMed

    Kolosovas-Machuca, Eleazar S; Martínez-Jiménez, Mario A; Ramírez-GarcíaLuna, José L; González, Francisco J; Pozos-Guillen, Amaury J; Campos-Lara, Nadia P; Pierdant-Perez, Mauricio

    2016-01-01

    Background and Objective. Pain evaluation in children can be a difficult task, since it possesses sensory and affective components that are often hard to discriminate. Infrared thermography has previously been used as a diagnostic tool for pain detection in animals; therefore, the aim of this study was to assess the presence of temperature changes during dental extractions and to evaluate its correlation with heart rate changes as markers of pain and discomfort. Methods. Thermographic changes in the lacrimal caruncle and heart rate measurements were recorded in healthy children scheduled for dental extraction before and during the procedure and compared. Afterwards, correlation between temperature and heart rate was assessed. Results. We found significant differences in temperature and heart rate before the procedure and during the dental extraction (mean difference 4.07°C, p < 0.001, and 18.11 beats per minute, p < 0.001) and no evidence of correlation between both measurements. Conclusion. Thermographic changes in the lacrimal caruncle can be detected in patients who undergo dental extractions. These changes appear to be stable throughout time and to possess very little intersubject variation, thus making them a candidate for a surrogate marker of pain and discomfort. Future studies should be performed to confirm this claim. PMID:27445611

  12. Enhanced temperature variability in high-altitude climate change

    NASA Astrophysics Data System (ADS)

    Ohmura, Atsumu

    2012-12-01

    In the present article, monthly mean temperature at 56 stations assembled in 18 regional groups in 10 major mountain ranges of the world were investigated. The periods of the analysis covered the last 50 to 110 years. The author found that the variability of temperature in climatic time scale tends to increase with altitude in about 65 % of the regional groups. A smaller number of groups, 20 %, showed the fastest change at an intermediate altitude between the peaks (or ridges) and their foot, while the remaining small number of sites, 15 %, showed the largest trends at the foot of mountains. This tendency provides a useful base for considering and planning the climate impact evaluations. The reason for the amplification of temperature variation at high altitudes is traced back to the increasing diabatic processes in the mid- and high troposphere as a result of the cloud condensation. This situation results from the fact that the radiation balance at the earth's surface is transformed more efficiently into latent heat of evaporation rather than sensible heat, the ratio between them being 4 to 1. Variation in the surface evaporation is converted into heat upon condensation into cloud particles and ice crystals in the mid- and high troposphere. Therefore, this is the altitude where the result of the surface radiation change is effectively transferred. Further, the low temperature of the environment amplifies the effect of the energy balance variation on the surface temperature, as a result of the functional shape of Stefan-Boltzmann law. These processes altogether contribute to enhancing temperature variability at high altitudes. The altitude play s an important role in determining the temperature variability, besides other important factors such as topography, surface characteristics, cryosphere/temperature feedback and the frequency and intensity of an inversion. These processes have a profound effect not only on the ecosystem but also on glaciers and permafrost.

  13. Effect of microorganism on Greenland ice sheet surface temperature change

    NASA Astrophysics Data System (ADS)

    Shimada, R.; Takeuchi, N.; Aoki, T.

    2012-12-01

    Greenland ice sheet holds approximately 10% of the fresh water on earth. If it melts all, sea level rises about 7.2meter. It is reported that mass of Greenland ice sheet is decreasing with temperature rising of climate change. Melting of the coastal area is particularly noticeable. It is established that 4 to 23% of the sea level rising from 1993 to 2005 is caused by the melting of Greenland ice sheet. In 2010, amount of melting per year became the largest than the past. However many climate models aren't able to simulate the recent melting of snow and ice in the Arctic including Greenland. One of the possible causes is albedo reduction of snow and ice surface by light absorbing snow impurities such as black carbon and dust and by glacial microorganisms. But there are few researches for effect of glacial microorganism in wide area. So it is important to clarify the impact of glacial microorganisms in wide area. The purpose of this study is to clarify the effect of microorganism on Greenland ice sheet surface temperature change using satellite images of visible, near infrared and thermal infrared wavelength range and observation carried out in northwestern Greenland. We use MODIS Land Surface Temperature Product as ice sheet surface temperature. It estimates land surface temperature based on split window method using thermal infrared bands. MODIS data is bound to cover the whole of Greenland, and calculated the ratio of the temperature change per year. Analysis period is from December 2002 to November 2010. Results of calculating Greenland ice sheet surface temperature change using the MODIS data, our analysis shows that it is upward trend in the whole region. We find a striking upward trend in northern and western part of Greenland. The rate is 0.33±0.03 degree Celsius per a year from 47.5°W to 49°W. While in the coastal area from 49°W to 50.7°W, the rate is 0.26±0.06 degree Celsius per a year. This large upward trend area is the same area as dark region

  14. Surface Temperatures on Titan; Changes During the Cassini Mission

    NASA Technical Reports Server (NTRS)

    Jennings, Donald E.; Cottini, Valeria; Nixon, Conor A.

    2010-01-01

    Surface brightness temperatures on Titan measured by the Composite Infrared Spectrometer (CIRS) aboard Cassini span the period from late northern winter to early spring. The CIRS observations cover all latitudes and can be used to study meridional changes with season. CIRS previously reported surface temperatures from 2004-2008 which were 93.7 K at the equator with decreases of 2 K toward the south pole and 3 K toward the north pole'. From a comparison of the equinox period with the earlier data, CIRS can now detect a seasonal shift in the latitudinal distribution of temperatures. Around the time of the equinox the meridional distribution was more symmetric about the equator than had been found earlier in the mission. The equatorial surface temperatures remained close to 94 K, but in the south the temperatures had decreased by about 0.5 K and in the north had increased by about 0.5 K. The CIRS equinox results are similar to what was seen near the previous vernal equinox by Voyager IRIS Z. The observed surface temperatures can help constrain the type of surface material by comparison with predictions from general circulation models. Of the three cases treated by Tokano t , our measurements most closely match a porous-ice regolith. As Cassini continues through Titan's northern spring CIRS will extend its temporal and spatial coverage and will continue to search for seasonal variations in surface temperature.

  15. Perceived temperature in the course of climate change: an analysis of global heat index from 1979 to 2013

    NASA Astrophysics Data System (ADS)

    Lee, D.; Brenner, T.

    2015-08-01

    The increase in global mean temperatures resulting from climate change has wide reaching consequences for the earth's ecosystems and other natural systems. Many studies have been devoted to evaluating the distribution and effects of these changes. We go a step further and propose the use of the heat index, a measure of the temperature as perceived by humans, to evaluate global changes. The heat index, which is computed from temperature and relative humidity, is more important than temperature for the health of humans and animals. Even in cases where the heat index does not reach dangerous levels from a health perspective, it has been shown to be an important factor in worker productivity and thus in economic productivity. We compute the heat index from dew point temperature and absolute temperature 2 m above ground from the ERA-Interim reanalysis data set for the years 1979-2013. The described data set provides global heat index aggregated to daily minima, means and maxima per day (doi:10.1594/PANGAEA.841057). This paper examines these data, as well as showing aggregations to monthly and yearly values. Furthermore, the data are spatially aggregated to the level of countries after being weighted by population density in order to facilitate the analysis of its impact on human health and productivity. The resulting data deliver insights into the spatiotemporal development of near-ground heat index during the course of the past three decades. It is shown that the impact of changing heat index is unevenly distributed through space and time, affecting some areas differently than others. The data can serve as a basis for evaluating and understanding the evolution of heat index in the course of climate change, as well as its impact on human health and productivity.

  16. Attribution of extreme temperature changes during 1951-2010

    NASA Astrophysics Data System (ADS)

    Kim, Yeon-Hee; Min, Seung-Ki; Zhang, Xuebin; Zwiers, Francis; Alexander, Lisa V.; Donat, Markus G.; Tung, Yu-Shiang

    2016-03-01

    An attribution analysis of extreme temperature changes is conducted using updated observations (HadEX2) and multi-model climate simulation (CMIP5) datasets for an extended period of 1951-2010. Compared to previous HadEX/CMIP3-based results, which identified human contributions to the observed warming of extreme temperatures on global and regional scales, the current results provide better agreement with observations, particularly for the intensification of warm extremes. Removing the influence of two major modes of natural internal variability (the Arctic Oscillation and Pacific Decadal Oscillation) from observations further improves attribution results, reducing the model-observation discrepancy in cold extremes. An optimal fingerprinting technique is used to compare observed changes in annual extreme temperature indices of coldest night and day (TNn, TXn) and warmest night and day (TNx, TXx) with multi-model simulated changes that were simulated under natural-plus-anthropogenic and natural-only (NAT) forcings. Extreme indices are standardized for better intercomparisons between datasets and locations prior to analysis and averaged over spatial domains from global to continental regions following a previous study. Results confirm previous HadEX/CMIP3-based results in which anthropogenic (ANT) signals are robustly detected in the increase in global mean and northern continental regional means of the four indices of extreme temperatures. The detected ANT signals are also clearly separable from the response to NAT forcing, and results are generally insensitive to the use of different model samples as well as different data availability.

  17. Small lakes show muted climate change signal in deepwater temperatures

    USGS Publications Warehouse

    Winslow, Luke A.; Read, Jordan S.; Hansen, Gretchen J. A.; Hanson, Paul C.

    2015-01-01

    Water temperature observations were collected from 142 lakes across Wisconsin, USA, to examine variation in temperature of lakes exposed to similar regional climate. Whole lake water temperatures increased across the state from 1990 to 2012, with an average trend of 0.042°C yr−1 ± 0.01°C yr−1. In large (>0.5 km2) lakes, the positive temperature trend was similar across all depths. In small lakes (<0.5 km2), the warming trend was restricted to shallow waters, with no significant temperature trend observed in water >0.5 times the maximum lake depth. The differing response of small versus large lakes is potentially a result of wind-sheltering reducing turbulent mixing magnitude in small lakes. These results demonstrate that small lakes respond differently to climate change than large lakes, suggesting that current predictions of impacts to lakes from climate change may require modification.

  18. Bhutan Rivers Runoff Sensitivity to Changes in Precipitation and Temperature

    NASA Astrophysics Data System (ADS)

    Sonessa, M. Y.; Richey, J. E.; Lettenmaier, D. P.

    2012-12-01

    The Kingdom of Bhutan harnesses its water resources mostly for hydropower generation. Hydroelectricity represents 96% of the country's electricity generating capacity and 99.9% of its electricity generation. About 87% of the electricity generated within Bhutan is exported to India. Assessment of this crucial resource is vital for its proper usage and management especially in the light of potential land use and climate changes. A land surface hydrologic model, Variable Infiltration Capacity (VIC), was used to assess the hydrology of the country. The model was forced using data obtained from three sources: NCEP/NCAR, Weather Research and Forecasting (WRF) and ERA Interim. The NCEP/NCAR forcing resulted in better flow simulation for most of the stations than WRF and ERA forcings. Thus, NCEP/NCAR forcing data was used to evaluate the runoff sensitivity to temperature and precipitation changes. In both steps, VIC was run at 1/24° latitude-longitude resolution. The modeled mean annual runoff elasticity which measures fractional change in annual runoff divided by fractional change in annual precipitation ranges from 1.08 to 2.16. The elasticity value is lower for higher reference precipitations and vice versa. The runoff sensitivity to temperature change computed as percentage change in annual runoff per 1°C change in temperature are all declines and ranges from -1.38 to -1.54. Spatially, both higher elasticity and sensitivity (big negatives) are towards the northern part the country where elevation is more than 5000 m above sea level.

  19. Phasic temperature change patterns affect growth and tuberization in potatoes

    SciTech Connect

    Cao, W.; Tibbitts, T.W. . Dept. of Horticulture)

    1994-07-01

    This study determined the response of potato (Solanum tuberosum L., cv. Norland) plants to various patterns of air temperature changes over different growth periods. In each of two experiments under controlled environments, eight treatments of temperature changes were carried out in two growth rooms maintained at 17 and 22 C and a constant vapor pressure deficit of 0.60 kPa and 14-hour photoperiod. Plants were grown for 63 days after transplanting of tissue culture plantlets in 20-liter pots containing peat-vermiculite mix. Temperature changes were imposed on days 21 and 42, which were essentially at the beginning of tuber initiation and tuber enlargement, respectively, for this cultivar. Plants were moved between two temperature rooms to obtain eight temperature change patterns: 17-17-17, 17-17-22, 17-22-17, 22-17-17, 17-22-22, 22-17-22, 22-22-17, and 22-22-22C over three 21-day growth periods. At harvest on day 63, total plant dry weight was higher for the treatments beginning with 22 C than for those beginning with 17C, with highest biomass obtained at 22-22-17 and 22-17-17C. Shoot dry weight increased with temperature increased from 17-17-17 to 22-22-22C during the three growth periods. Tuber dry weight was highest with 22-17-17C, and lowest with 17-17-22 and 17-22-22C. With 22-17-17C, both dry weights of stolons and roots were lowest. Total tuber number and number of small tubers were highest with 17-17-17 and 17-17-22C, and lowest with 17-22-22 and 22-22-22C, whereas number of medium tubers was highest with 22-17-22C, and number of large tubers was highest with 22-17-17C. This study indicates that tuber development of potatoes is optimized with a phasic pattern of high temperature during early growth and low temperature during later growth.

  20. Negativity Bias in Dangerous Drivers

    PubMed Central

    Chai, Jing; Qu, Weina; Sun, Xianghong; Zhang, Kan; Ge, Yan

    2016-01-01

    The behavioral and cognitive characteristics of dangerous drivers differ significantly from those of safe drivers. However, differences in emotional information processing have seldom been investigated. Previous studies have revealed that drivers with higher anger/anxiety trait scores are more likely to be involved in crashes and that individuals with higher anger traits exhibit stronger negativity biases when processing emotions compared with control groups. However, researchers have not explored the relationship between emotional information processing and driving behavior. In this study, we examined the emotional information processing differences between dangerous drivers and safe drivers. Thirty-eight non-professional drivers were divided into two groups according to the penalty points that they had accrued for traffic violations: 15 drivers with 6 or more points were included in the dangerous driver group, and 23 drivers with 3 or fewer points were included in the safe driver group. The emotional Stroop task was used to measure negativity biases, and both behavioral and electroencephalograph data were recorded. The behavioral results revealed stronger negativity biases in the dangerous drivers than in the safe drivers. The bias score was correlated with self-reported dangerous driving behavior. Drivers with strong negativity biases reported having been involved in mores crashes compared with the less-biased drivers. The event-related potentials (ERPs) revealed that the dangerous drivers exhibited reduced P3 components when responding to negative stimuli, suggesting decreased inhibitory control of information that is task-irrelevant but emotionally salient. The influence of negativity bias provides one possible explanation of the effects of individual differences on dangerous driving behavior and traffic crashes. PMID:26765225

  1. Changes in diurnal temperature range and national cereal yields

    SciTech Connect

    Lobell, D

    2007-04-26

    Models of yield responses to temperature change have often considered only changes in average temperature (Tavg), with the implicit assumption that changes in the diurnal temperature range (DTR) can safely be ignored. The goal of this study was to evaluate this assumption using a combination of historical datasets and climate model projections. Data on national crop yields for 1961-2002 in the 10 leading producers of wheat, rice, and maize were combined with datasets on climate and crop locations to evaluate the empirical relationships between Tavg, DTR, and crop yields. In several rice and maize growing regions, including the two major nations for each crop, there was a clear negative response of yields to increased DTR. This finding reflects a nonlinear response of yields to temperature, which likely results from greater water and heat stress during hot days. In many other cases, the effects of DTR were not statistically significant, in part because correlations of DTR with other climate variables and the relatively short length of the time series resulted in wide confidence intervals for the estimates. To evaluate whether future changes in DTR are relevant to crop impact assessments, yield responses to projected changes in Tavg and DTR by 2046-2065 from 11 climate models were estimated. The mean climate model projections indicated an increase in DTR in most seasons and locations where wheat is grown, mixed projections for maize, and a general decrease in DTR for rice. These mean projections were associated with wide ranges that included zero in nearly all cases. The estimated impacts of DTR changes on yields were generally small (<5% change in yields) relative to the consistently negative impact of projected warming of Tavg. However, DTR changes did significantly affect yield responses in several cases, such as in reducing US maize yields and increasing India rice yields. Because DTR projections tend to be positively correlated with Tavg, estimates of yields

  2. Skin temperature changes induced by strong static magnetic field exposure.

    PubMed

    Ichioka, Shigeru; Minegishi, Masayuki; Iwasaka, Masakazu; Shibata, Masahiro; Nakatsuka, Takashi; Ando, Joji; Ueno, Shoogo

    2003-09-01

    High intensity static magnetic fields, when applied to the whole body of the anesthetized rat, have previously been reported to decrease skin temperature. The hypothesis of the present study was that in diamagnetic water, molecules in the air play significant roles in the mechanism of skin temperature decrease. We used a horizontal cylindrical superconducting magnet. The magnet produced 8 T at its center. A thermistor probe was inserted in a subcutaneous pocket of the anesthetized rats to measure skin temperature. Animals (n=10) were placed in an open plastic holder in which the ambient air was free to move in any direction (group I). Animals (n=10) were placed in a closed holder in which the air circulation toward the direction of weak magnetic field was restricted (group II). Each holder was connected to a hydrometer to measure humidity around the animal in the holder. The data acquisition phase consisted of a 5 min baseline interval, followed by inserting the animal together with the holder into the center of the magnet bore for a 5 min exposure and a 5 min postexposure period outside the bore. In group I, skin temperature and humidity around the animal significantly decreased during exposure, followed by recovery after exposure. In group II, skin temperature and humidity did not decrease during the measurement. The skin temperature decrease was closely related to the decrease in humidity around the body of the animal in the holder, and the changes were completely blocked by restricting the air circulation in the direction of the bore entrance. Possible mechanisms responsible for the decrease in skin temperature may be associated with magnetically induced movement of water vapor at the skin surface, leading to skin temperature decrease. PMID:12929156

  3. Main Dangers of Our Times.

    NASA Astrophysics Data System (ADS)

    Synek, Miroslav

    2003-03-01

    Terrorism and threatening dictatorships are the main, man-made, dangers of our times. They are run by master demagogues, or, brain-washing manipulators. ----- Our next step in coping with terrorism is to counter master demagoguery. Therefore, supporting EDUCATION that would emphasize the most unifying (and the least controversial), yet, BASIC CIVIC RESPECT for lives of people in a civilian human society, is a priority everywhere on our planet. ----- At the same time we start facing mostly small, threatening, dictatorships, capable of producing weapons of mass destruction. Therefore, we have to try to contribute to developing systems of FREE ELECTIONS, controlling weapons of mass destruction, wherever such dangers exist. ----- In a foreseeable future, unfortunately, we are facing a danger even by orders of magnitude greater. We are facing a possibility of a mass-produced heavy accumulation of inter-continental nuclear missiles, on a computerized "push-button" control, by a very powerful (and, quite possibly, miscalculating, or, suicidal) dictator, dangerous to the very existence of humanity on our planet. Therefore, it is a historical urgency that such a technological power be under the control by a government of the people, by the people and for the people, based on a sufficiently reliable system of FREE ELECTIONS, wherever, on our planet, such a potential danger may originate.

  4. Reconciling anthropogenic climate change with observed temperature 1998–2008

    PubMed Central

    Kaufmann, Robert K.; Kauppi, Heikki; Mann, Michael L.; Stock, James H.

    2011-01-01

    Given the widely noted increase in the warming effects of rising greenhouse gas concentrations, it has been unclear why global surface temperatures did not rise between 1998 and 2008. We find that this hiatus in warming coincides with a period of little increase in the sum of anthropogenic and natural forcings. Declining solar insolation as part of a normal eleven-year cycle, and a cyclical change from an El Nino to a La Nina dominate our measure of anthropogenic effects because rapid growth in short-lived sulfur emissions partially offsets rising greenhouse gas concentrations. As such, we find that recent global temperature records are consistent with the existing understanding of the relationship among global surface temperature, internal variability, and radiative forcing, which includes anthropogenic factors with well known warming and cooling effects. PMID:21730180

  5. Reconciling anthropogenic climate change with observed temperature 1998-2008.

    PubMed

    Kaufmann, Robert K; Kauppi, Heikki; Mann, Michael L; Stock, James H

    2011-07-19

    Given the widely noted increase in the warming effects of rising greenhouse gas concentrations, it has been unclear why global surface temperatures did not rise between 1998 and 2008. We find that this hiatus in warming coincides with a period of little increase in the sum of anthropogenic and natural forcings. Declining solar insolation as part of a normal eleven-year cycle, and a cyclical change from an El Nino to a La Nina dominate our measure of anthropogenic effects because rapid growth in short-lived sulfur emissions partially offsets rising greenhouse gas concentrations. As such, we find that recent global temperature records are consistent with the existing understanding of the relationship among global surface temperature, internal variability, and radiative forcing, which includes anthropogenic factors with well known warming and cooling effects. PMID:21730180

  6. Generating a wave from a wall with changing temperature

    NASA Astrophysics Data System (ADS)

    Sakurai, A.; Tsukamoto, M.; Takahashi, S.

    2012-11-01

    Under the purpose to provide a foundation for the numerical approach, the problem of wave generation from a wall with changing temperature is considered to analytically solve the linear Boltzmann-BGK equation with diffuse reflection at a wall by successive approximation. Convergence is verified, and approximate solutions used in its proof are utilized to demonstrate its wave-like features observed in the numerical solution.

  7. Danger warrants rescuing data

    NASA Astrophysics Data System (ADS)

    Shaw, George H.

    A plea as plaintive as that of Marcia Neugebauer should not go unheeded. The problem she cites presents potentially serious problems for science and deserves further thought and discussion. Linguists will tell us that the inevitable evolution of language results from modifications of meaning and usage in response to changing aspects of the human condition. Nevertheless, in the misappropriation of “data” there is enough at stake to warrant strong efforts to oppose the trend.

  8. Effects of temperature changes on maize production in Mozambique

    USGS Publications Warehouse

    Harrison, L.; Michaelsen, J.; Funk, C.; Husak, G.

    2011-01-01

    We examined intraseasonal changes in maize phenology and heat stress exposure over the 1979-2008 period, using Mozambique meteorological station data and maize growth requirements in a growing degree-day model. Identifying historical effects of warming on maize growth is particularly important in Mozambique because national food security is highly dependent on domestic food production, most of which is grown in already warm to hot environments. Warming temperatures speed plant development, shortening the length of growth periods necessary for optimum plant and grain size. This faster phenological development also alters the timing of maximum plant water demand. In hot growing environments, temperature increases during maize pollination threaten to make midseason crop failure the norm. In addition to creating a harsher thermal environment, we find that early season temperature increases have caused the maize reproductive period to start earlier, increasing the risk of heat and water stress. Declines in time to maize maturation suggest that, independent of effects to water availability, yield potential is becoming increasingly limited by warming itself. Regional variations in effects are a function of the timing and magnitude of temperature increases and growing season characteristics. Continuation of current climatic trends could induce substantial yield losses in some locations. Farmers could avoid some losses through simple changes to planting dates and maize varietal types.

  9. Power change in amorphous silicon technology by low temperature annealing

    NASA Astrophysics Data System (ADS)

    Mittal, Ankit; Rennhofer, Marcus; Dangel, Angelika; Duman, Bogdan; Schlosser, Victor

    2015-07-01

    Amorphous silicon (a-Si) is one of the best established thin-film solar-cell technologies. Despite its long history of research, it still has many critical issues because of its defect rich material and its susceptibility to degrade under light also called as Staebler-Wronski effect (SWE). This leads to an increase in the defect density of a-Si, but as a metastable effect it can be completely healed at temperatures above 170 °C. Our study is focused on investigating the behavior of annealing of different a-Si modules under low temperature conditions below 80 °C indicated by successive change of module power. These conditions reflect the environmental temperature impact of the modules in the field, or integrated in buildings as well. The power changes were followed by STC power rating and investigation of module-power evolution under low irradiance conditions at 50 W/m2. Our samples were recovered close to their initial state of power, reaching as high as 99% from its degraded value. This shows the influence of low temperature annealing and light on metastable module behavior in a-Si thin-film modules.

  10. What matters most: Are summer stream temperatures more sensitive to changing air temperature, changing discharge, or changing riparian vegetation under future climates?

    NASA Astrophysics Data System (ADS)

    Diabat, M.; Haggerty, R.; Wondzell, S. M.

    2012-12-01

    We investigated stream temperature responses to changes in both air temperature and stream discharge projected for 2040-2060 from downscaled GCMs and changes in the height and canopy density of streamside vegetation. We used Heat Source© calibrated for a 37 km section of the Middle Fork John Day River located in Oregon, USA. The analysis used the multiple-variable-at-a-time (MVAT) approach to simulate various combinations of changes: 3 levels of air warming, 5 levels of stream flow (higher and lower discharges), and 6 types of streamside vegetation. Preliminary results show that, under current discharge and riparian vegetation conditions, projected 2 to 4 °C increase in air temperature will increase the 7-day Average Daily Maximum Temperature (7dADM) by 1 to 2 °C. Changing stream discharge by ±30% changes stream temperature by ±0.5 °C, and the influence of changing discharge is greatest when the stream is poorly shaded. In contrast, the 7dADM could change by as much as 11°C with changes in riparian vegetation from unshaded conditions to heavily shaded conditions along the study section. The most heavily shaded simulations used uniformly dense riparian vegetation over the full 37-km reach, and this vegetation was composed of the tallest trees and densest canopies that can currently occur within the study reach. While this simulation represents an extreme case, it does suggest that managing riparian vegetation to substantially increase stream shade could decrease 7dADM temperatures relative to current temperatures, even under future climates when mean air temperatures have increased from 2 to 4 °C.

  11. Temperature Changes in Brown Adipocytes Detected with a Bimaterial Microcantilever

    PubMed Central

    Sato, Masaaki K.; Toda, Masaya; Inomata, Naoki; Maruyama, Hisataka; Okamatsu-Ogura, Yuko; Arai, Fumihito; Ono, Takahito; Ishijima, Akihiko; Inoue, Yuichi

    2014-01-01

    Mammalian cells must produce heat to maintain body temperature and support other biological activities. Methods to measure a cell’s thermogenic ability by inserting a thermometer into the cell or measuring the rate of oxygen consumption in a closed vessel can disturb its natural state. Here, we developed a noninvasive system for measuring a cell’s heat production with a bimaterial microcantilever. This method is suitable for investigating the heat-generating properties of cells in their native state, because changes in cell temperature can be measured from the bending of the microcantilever, without damaging the cell and restricting its supply of dissolved oxygen. Thus, we were able to measure increases in cell temperature of <1 K in a small number of murine brown adipocytes (n = 4–7 cells) stimulated with norepinephrine, and observed a slow increase in temperature over several hours. This long-term heat production suggests that, in addition to converting fatty acids into heat energy, brown adipocytes may also adjust protein expression to raise their own temperature, to generate more heat. We expect this bimaterial microcantilever system to prove useful for determining a cell’s state by measuring thermal characteristics. PMID:24896125

  12. Large diurnal temperature range increases bird sensitivity to climate change

    PubMed Central

    Briga, Michael; Verhulst, Simon

    2015-01-01

    Climate variability is changing on multiple temporal scales, and little is known of the consequences of increases in short-term variability, particularly in endotherms. Using mortality data with high temporal resolution of zebra finches living in large outdoor aviaries (5 years, 359.220 bird-days), we show that mortality rate increases almost two-fold per 1°C increase in diurnal temperature range (DTR). Interestingly, the DTR effect differed between two groups with low versus high experimentally manipulated foraging costs, reflecting a typical laboratory ‘easy’ foraging environment and a ‘hard’ semi-natural environment respectively. DTR increased mortality on days with low minimum temperature in the easy foraging environment, but on days with high minimum temperature in the semi-natural environment. Thus, in a natural environment DTR effects will become increasingly important in a warming world, something not detectable in an ‘easy’ laboratory environment. These effects were particularly apparent at young ages. Critical time window analyses showed that the effect of DTR on mortality is delayed up to three months, while effects of minimum temperature occurred within a week. These results show that daily temperature variability can substantially impact the population viability of endothermic species. PMID:26563993

  13. LED Curing Lights and Temperature Changes in Different Tooth Sites

    PubMed Central

    Armellin, E.; Bovesecchi, G.; Coppa, P.; Pasquantonio, G.; Cerroni, L.

    2016-01-01

    Objectives. The aim of this in vitro study was to assess thermal changes on tooth tissues during light exposure using two different LED curing units. The hypothesis was that no temperature increase could be detected within the dental pulp during polymerization irrespective of the use of a composite resin or a light-curing unit. Methods. Caries-free human first molars were selected, pulp residues were removed after root resection, and four calibrated type-J thermocouples were positioned. Two LED lamps were tested; temperature measurements were made on intact teeth and on the same tooth during curing of composite restorations. The data was analyzed by one-way analysis of variance (ANOVA), Wilcoxon test, Kruskal-Wallis test, and Pearson's χ2. After ANOVA, the Bonferroni multiple comparison test was performed. Results. Polymerization data analysis showed that in the pulp chamber temperature increase was higher than that without resin. Starlight PRO, in the same condition of Valo lamp, showed a lower temperature increase in pre- and intrapolymerization. A control group (without composite resin) was evaluated. Significance. Temperature increase during resin curing is a function of the rate of polymerization, due to the exothermic polymerization reaction, the energy from the light unit, and time of exposure. PMID:27195282

  14. Rapid Middle Eocene temperature change in western North America

    NASA Astrophysics Data System (ADS)

    Methner, Katharina; Mulch, Andreas; Fiebig, Jens; Wacker, Ulrike; Gerdes, Axel; Graham, Stephan A.; Chamberlain, C. Page

    2016-09-01

    Eocene hyperthermals are among the most enigmatic phenomena of Cenozoic climate dynamics. These hyperthermals represent temperature extremes superimposed on an already warm Eocene climate and dramatically affected the marine and terrestrial biosphere, yet our knowledge of temperature and rainfall in continental interiors is still rather limited. We present stable isotope (δ18O) and clumped isotope temperature (Δ47) records from a middle Eocene (41 to 40 Ma) high-elevation mammal fossil locality in the North American continental interior (Montana, USA). Δ47 paleotemperatures of soil carbonates delineate a rapid +9/-11 °C temperature excursion in the paleosol record. Δ47 temperatures progressively increase from 23 °C ± 3 °C to peak temperatures of 32 °C ± 3 °C and subsequently drop by 11 °C. This hyperthermal event in the middle Eocene is accompanied by low δ18O values and reduced pedogenic carbonate concentrations in paleosols. Based on laser ablation U/Pb geochronology of paleosol carbonates in combination with magnetostratigraphy, biostratigraphy, stable isotope, and Δ47 evidence, we suggest that this pronounced warming event reflects the Middle Eocene Climatic Optimum (MECO) in western North America. The terrestrial expression of northern hemisphere MECO in western North America appears to be characterized by warmer and wetter (sub-humid) conditions, compared to the post-MECO phase. Large and rapid shifts in δ18O values of precipitation and pedogenic CaCO3 contents parallel temperature changes, indicating the profound impact of the MECO on atmospheric circulation and rainfall patterns in the western North American continental interior during this transient warming event.

  15. Changing fitness of a necrotrophic plant pathogen under increasing temperature.

    PubMed

    Sabburg, Rosalie; Obanor, Friday; Aitken, Elizabeth; Chakraborty, Sukumar

    2015-08-01

    Warmer temperatures associated with climate change are expected to have a direct impact on plant pathogens, challenging crops and altering plant disease profiles in the future. In this study, we have investigated the effect of increasing temperature on the pathogenic fitness of Fusarium pseudograminearum, an important necrotrophic plant pathogen associated with crown rot disease of wheat in Australia. Eleven wheat lines with different levels of crown rot resistance were artificially inoculated with F. pseudograminearum and maintained at four diurnal temperatures 15/15°C, 20/15°C, 25/15°C and 28/15°C in a controlled glasshouse. To quantify the success of F. pseudograminearum three fitness measures, these being disease severity, pathogen biomass in stem base and flag leaf node, and deoxynivalenol (DON) in stem base and flag leaf node of mature plants were used. F. pseudograminearum showed superior overall fitness at 15/15°C, and this was reduced with increasing temperature. Pathogen fitness was significantly influenced by the level of crown rot resistance of wheat lines, but the influence of line declined with increasing temperature. Lines that exhibited superior crown rot resistance in the field were generally associated with reduced overall pathogen fitness. However, the relative performance of the wheat lines was dependent on the measure of pathogen fitness, and lines that were associated with one reduced measure of pathogen fitness did not always reduce another. There was a strong correlation between DON in stem base tissue and disease severity, but length of browning was not a good predictor of Fusarium biomass in the stem base. We report that a combination of host resistance and rising temperature will reduce pathogen fitness under increasing temperature, but further studies combining the effect of rising CO2 are essential for more realistic assessments. PMID:25767051

  16. Carbon dioxide dangers demonstration model

    USGS Publications Warehouse

    Venezky, Dina; Wessells, Stephen

    2010-01-01

    Carbon dioxide is a dangerous volcanic gas. When carbon dioxide seeps from the ground, it normally mixes with the air and dissipates rapidly. However, because carbon dioxide gas is heavier than air, it can collect in snowbanks, depressions, and poorly ventilated enclosures posing a potential danger to people and other living things. In this experiment we show how carbon dioxide gas displaces oxygen as it collects in low-lying areas. When carbon dioxide, created by mixing vinegar and baking soda, is added to a bowl with candles of different heights, the flames are extinguished as if by magic.

  17. Interdecadal changes of surface temperature since the late nineteenth century

    SciTech Connect

    Parker, D.E.; Folland, C.K.; Bevan, A.; Jones, P.D.

    1994-07-20

    The authors present global fields of decadal annual surface temperature anomalies, referred to the period 1951-1980, for each decade from 1881-1890 to 1981-1990 and for 1984-1993. In addition, they show decadal calendar-seasonal anomaly fields for the warm decades 1936-1945 and 1981-1990. The fields are based on sea surface temperature (SST) and land surface air temperature data. The SSTs are corrected for the pre-World War II use of uninsulated sea temperature buckets and incorporate adjusted satellite-based SSTs from 1982 onward. These results extend those published in the 1990 Intergovernmental Panel on Climate Change Scientific Assessment. Despite poor data coverage initially and around the two World Wars the generally cold end of the nineteenth century and start to the twentieth century are confirmed, together with the substantial warming between about 1920 and 1940. Slight cooling of the northern hemisphere took place between the 1950s and the mid-1970s, although slight warming continued south of the equator. Recent warmth has been most marked over the northern continents in winter and spring, but the 1980s were warm almost everywhere apart from Greenland, the northwestern Atlantic and the midlatitude North Pacific. Parts of the middle- to high-latitude southern ocean may also have been cool in the 1980s, but in this area the 1951-1980 climatology is unreliable. The impact of the satellite data is reduced because the record of blended satellite and in situ SST is still too short to yield a climatology from which to calculate representative anomalies reflecting climatic change in the southern ocean. However, the authors propose a method of using existing satellite data in a step toward this target. The maps are condensed into global and hemispheric decadal surface temperature anomalies. The authors show the sensitivity of these estimated anomalies to alternative methods of compositing the spatially incomplete fields. 58 refs., 17 figs., 3 tabs.

  18. Temperature changes across CO2-lased dentin during multiple exposures

    NASA Astrophysics Data System (ADS)

    Zakariasen, Kenneth L.; Barron, Joseph R.; Boran, Thomas L.

    1990-06-01

    The literature increasingly indicates that lasers will have a multitude of applications for dental hard tissue procedures, e.g. preventive therapy, caries removal, laser etching and endodontic therapy. However, it is critical that such laser therapies avoid the production of heat levels which will be damaging to the surrounding vital tissues, such as the dental pulp and periodontal tissues. Our preliminary research on temperature changes across C02 lased dentin indicated that for single preventive therapeutic exposures (1.2 W., 0. 1 sec., 1.0 mm focal spot) the mean temperature rise across 350 j.tm of dentin was 0.57 0C while across 1000 .tm of dentin the mean rise was only 0.18 °C. Further research utilizing multiple preventive therapeutic exposures (1.2 W., 0. 1 sec., 1.0 mm focal spot, 3 x 1.0 sec. intervals) showed mean temperature elevations of 1.56 0C across 350 m of dentin and 0.66 O across 1000 xm of dentin. While these temperature elevations, which would be associated with preventive therapy, are very low and would be biologically acceptable, it must be noted that exposures of higher intensities are required to fuse enamel and porcelain, or remove decay. This current research investigates temperature elevations which occuT during C02 lasing utilizing the following exposure parameters: 8.0 W., 1.0 mm focal spot, 0.1 sec. exposures, 2 or 4 exposures per site pulsed 1.0 sec. apart. Three dentin thicknesses were utilized, i.e. 1000 jim, 1500 p.tm and 2000 .tm. Four sections of each thickness were utilized with four exposure sites per specimen (2 with 2 exposures, 2 with 4 exposures). All dentin sections were prepared from non-carious third molars using a hard tissue microtome. A thermistor was placed on the dentin surface opposite each lased site and temperature changes were recorded for approximately 50 sec. following lasing. Mean temperature elevations ranged from a high of 3.07 C for the 1000 xm section utilizing four exposures to a low of 0.37 0C for the

  19. Improving the estimation of historical marine surface temperature changes

    NASA Astrophysics Data System (ADS)

    Carella, Giulia; Kent, Elizabeth C.; Berry, David I.

    2015-04-01

    Global Surface Temperature (GST) is one of the main indicators of climate change and Sea Surface Temperature (SST) forms its marine component. Historical SST observations extend back more than 150 years and are used for monitoring climate change and variability over the oceans, for validation of climate models and to provide boundary conditions for atmospheric models. SST observations from ships form our longest instrumental record of surface marine temperature change, but over the years different methods of measuring SST have been used, each of which potentially has different biases. Changes in technology and observational practice can be rapid and undocumented: generally, it is assumed that almost all SST data collected before the 1940s were derived from bucket samples although the measurement practice is almost never known in detail. Especially prior to the 1940s where buckets measurements prevailed, SST biases are expected to be large, namely comparable to the climatic increase in the GST over the past two centuries. Currently, SST datasets use bias models representing only large-scale effects, based on 5˚ area average monthly climatological environmental conditions or on large-scale variations in air-sea temperature difference, which is also uncertain. There are major differences between the bias adjustment fields used to date, which limits our confidence in global and regional estimates of historical SST as well as in long term trends, which are expected to be controlled by uncertainty in systematic biases. The main barrier to finer-scale adjustments of SST is that information about measurement methods and ambient environmental conditions is usually insufficient. As a result, many reports cannot be confidently assigned to a particular vessel and hence, cautiously, to the same measurement methodology. Here we present a new approach to the quantification of SST biases that can be applied on a ship-by-ship basis. These ship dependent adjustments are expected to

  20. Piglets’ Surface Temperature Change at Different Weights at Birth

    PubMed Central

    Caldara, Fabiana Ribeiro; dos Santos, Luan Sousa; Machado, Sivanilza Teixeira; Moi, Marta; de Alencar Nääs, Irenilza; Foppa, Luciana; Garcia, Rodrigo Garófallo; de Kássia Silva dos Santos, Rita

    2014-01-01

    The study was carried out in order to verify the effects of piglets’ weight at birth on their surface temperature change (ST) after birth, and its relationship with ingestion time of colostrum. Piglets from four different sows were weighed at birth and divided into a totally randomized design with three treatments according to birth weight (PBW): T1 - less than 1.00 kg, T2 - 1.00 to 1.39 kg, and T3 - higher than or equal to 1.40 kg. The time spent for the first colostrum ingestion was recorded (TFS). Images of piglets’ surface by thermal imaging camera were recorded at birth (STB) and 15, 30, 45, 60, and 120 min after birth. The air temperature and relative humidity were recorded every 30 min and the indexes of temperature and humidity (THI) were calculated. A ST drop after 15 min from birth was observed, increasing again after sixty minutes. Positive correlations were found between the PBW and the ST at 30 and 45 min after birth. The PBW was negatively correlated with the TFS. The THI showed high negative correlations (−0.824 and −0.815) with STB and after 15 min from birth. The piglet’s surface temperature at birth was positively correlated with temperature thereof to 15 min, influencing therefore the temperatures in the interval of 45 to 120 min. The birth weight contributes significantly to postnatal hypothermia and consequently to the time it takes for piglets ingest colostrum, requiring special attention to those of low birth weight. PMID:25049971

  1. Method for Measuring Collimator-Pointing Sensitivity to Temperature Changes

    NASA Technical Reports Server (NTRS)

    Abramovici, Alex; Cox, Timothy E.; Hein, Randall C.; MacDonald, Daniel R.

    2011-01-01

    For a variety of applications, it is important to measure the sensitivity of the pointing of a beam emerging from a collimator, as a function of temperature changes. A straightforward method for carrying out this measurement is based on using interferometry for monitoring the changes in beam pointing, which presents its own problems. The added temperature dependence and complexity issues relating to using an interferometer are addressed by not using an interferometer in the first place. Instead, the collimator is made part of an arrangement that uses a minimum number of low-cost, off-the-shelf materials and by using a quad diode to measure changes in beam pointing. In order to minimize the influence of the test arrangement on the outcome of the measurement, several steps are taken. The collimator assembly is placed on top of a vertical, 1-m-long, fused silica tube. The quad diode is bonded to a fused silica bar, which, in turn, is bonded to the lower end of the fused silica tube. The lower end of the tube rests on a self-aligning support piece, while the upper end of the tube is kept against two rounded setscrew tips, using a soft rubber string. This ensures that very little stress is applied to the tube as the support structure changes dimensions due to thermal expansion. Light is delivered to the collimator through a bare fiber in order to minimize variable bending torque caused by a randomly relaxing, rigid fiber jacket. In order to separate the effect of temperature on the collimator assembly from the effect temperature has on the rest of the setup, multiple measurements are taken with the collimator assembly rotated from measurement to measurement. Laboratory testing, with 1-m spacing between the collimator and the quad diode, has shown that the sensitivity of the arrangement is better than 100 nm rms, over time spans of at least one hour, if the beam path is protected from atmospheric turbulence by a tube. The equivalent sensitivity to detecting changes in

  2. Temperature changes along the Spanish Mediterranean shelf waters

    NASA Astrophysics Data System (ADS)

    Vargas-Yanez, M.; Lopez-Jurado, J. L.; Salat, J.; Pascual, J.

    2003-04-01

    Temperature and salinity of intermediate and deep waters of the western Mediterranean have rised during the XX century. These changes are well documented in the specialised literature (Bethoux et al., 1998, Rholing and Bryden, 1992, Tsimplis and Baker, 2000). Nevertheless it is not yet clear whether these changes are due to global warming and a change in the deep water formation conditions in the western Mediterranean or if it is imported from the eastern basin. In the second case, an increase of salinity of the eastern basin due to damming of the main rivers would be the main cause. Trend detection in coastal waters where intermediate waters influence is negligible, would help to clarify this problem. Nevertheless, it is more difficult to detect significant trends in coastal waters due to the intense noise and seasonal cycles superimposed to these trends (if existing). The number of degrees of freedom needed for the significant detection is higher and regular sampling programs are needed. Unfortunately, standard stations periodically sampled are scarce. Here we present results from two of these periodic programs conducted by IEO and ICM along the Spanish Mediterranean shelf (RADIALES project and L'startit coastal station). This work is divided into two parts. The first one is devoted to the revision of the main hypothesis involved in the statistic treatment of time series, such as normal distribution, independence of residuals, seasonal cycles removing, etc...., while the second part will focus on the comparison of time series along the Spanish coast, the study of temperature trends and its possible relation with NAO index. The most striking result is the detection of a intense warming trend which is common to the north-western and south-western stations for the last part of the XX century. Bibliography. Bethoux, J.P., B. Gentili, D. Taillez, warming and freshwater budget change in the Mediterranean since the 1940s, their possible relation to the greenhouse effect

  3. Students' Ideas about Dangerous Animals

    ERIC Educational Resources Information Center

    Cardak, Osman

    2009-01-01

    The aim of this article was to study the concepts and thoughts of primary education students about dangerous animals. A total of 316 primary education students attending a primary school in Turkey participated in the study. The research data was obtained through open-ended questions and word association tests. Data obtained from the questions…

  4. Northwestern Pacific typhoon intensity controlled by changes in ocean temperatures.

    PubMed

    Mei, Wei; Xie, Shang-Ping; Primeau, François; McWilliams, James C; Pasquero, Claudia

    2015-05-01

    Dominant climatic factors controlling the lifetime peak intensity of typhoons are determined from six decades of Pacific typhoon data. We find that upper ocean temperatures in the low-latitude northwestern Pacific (LLNWP) and sea surface temperatures in the central equatorial Pacific control the seasonal average lifetime peak intensity by setting the rate and duration of typhoon intensification, respectively. An anomalously strong LLNWP upper ocean warming has favored increased intensification rates and led to unprecedentedly high average typhoon intensity during the recent global warming hiatus period, despite a reduction in intensification duration tied to the central equatorial Pacific surface cooling. Continued LLNWP upper ocean warming as predicted under a moderate [that is, Representative Concentration Pathway (RCP) 4.5] climate change scenario is expected to further increase the average typhoon intensity by an additional 14% by 2100. PMID:26601179

  5. Northwestern Pacific Typhoon Intensity Controlled by Changes in Ocean Temperatures

    NASA Astrophysics Data System (ADS)

    Mei, W.; Xie, S. P.; Primeau, F.; McWilliams, J. C.; Pasquero, C.

    2015-12-01

    Dominant climatic factors controlling the lifetime peak intensity of typhoons are determined from six decades of Pacific typhoon data. We find that upper ocean temperatures in the low-latitude northwestern Pacific (LLNWP) and sea surface temperatures in the central equatorial Pacific control the seasonal average lifetime peak intensity by setting the rate and duration of typhoon intensification, respectively. An anomalously strong LLNWP upper ocean warming has favored increased intensification rates and led to unprecedentedly high average typhoon intensity during the recent global warming hiatus period, despite a reduction in intensification duration tied to the central equatorial Pacific surface cooling. Continued LLNWP upper ocean warming as predicted under a moderate (i.e., RCP 4.5) climate change scenario is expected to further increase the average typhoon intensity by an additional 14% by 2100.

  6. Northwestern Pacific typhoon intensity controlled by changes in ocean temperatures

    PubMed Central

    Mei, Wei; Xie, Shang-Ping; Primeau, François; McWilliams, James C.; Pasquero, Claudia

    2015-01-01

    Dominant climatic factors controlling the lifetime peak intensity of typhoons are determined from six decades of Pacific typhoon data. We find that upper ocean temperatures in the low-latitude northwestern Pacific (LLNWP) and sea surface temperatures in the central equatorial Pacific control the seasonal average lifetime peak intensity by setting the rate and duration of typhoon intensification, respectively. An anomalously strong LLNWP upper ocean warming has favored increased intensification rates and led to unprecedentedly high average typhoon intensity during the recent global warming hiatus period, despite a reduction in intensification duration tied to the central equatorial Pacific surface cooling. Continued LLNWP upper ocean warming as predicted under a moderate [that is, Representative Concentration Pathway (RCP) 4.5] climate change scenario is expected to further increase the average typhoon intensity by an additional 14% by 2100. PMID:26601179

  7. Repeat temperature measurements in borehole GC-1, northwestern Utah - Towards isolating a climate-change signal in borehole temperature profiles

    SciTech Connect

    Chapman, D.S.; Harris, R.N. )

    1993-09-01

    Temperature-depth profiles in borehole GC-1, northwestern Utah, were measured in 1978, 1990, and 1992. Borehole temperatures below 80 m depth are highly reproducible over the 14 year period indicating long term thermal stability. A slowly changing temperature field above 80 m depth has similiar characteristics to synthetic temperature profiles computed from a 100 year record of air temperature changes at Park Valley weather station 50 km northeast of the borehole site. 6 refs.

  8. Temperature changes in spectral characteristics of electrons in metallic lithium

    SciTech Connect

    Popov, V.A.

    1995-12-01

    Self-consistent calculations of the electron energy structure in metallic lithium are performed taking into account atomic vibrations in the crystal lattice. A satisfactory agreement between the results of calculations and experimental data is achieved. The most significant changes in the electron spectrum of lithium revealed with rising temperature are as follows: (1) shift and broadening of core states of the 1s-asymmetry and (2) transition of outer electrons of the 2s-symmetry to the states of the 2p-symmetry leading to strengthening of the directional bonds. 10 refs., 1 fig., 1 tab.

  9. Repeat temperature measurements in boreholes from northwestern Utah link ground and air temperature changes at the decadal time scale

    NASA Astrophysics Data System (ADS)

    Davis, Michael G.; Harris, Robert N.; Chapman, David S.

    2010-05-01

    Borehole temperature profiles provide a record of ground surface temperature (GST) change at the decadal to centennial time scale. GST histories reconstructed from boreholes are particularly useful in climate reconstruction if changes in GST and surface air temperature (SAT) are effectively coupled at decadal and longer time periods and it can be shown that borehole temperatures respond faithfully to surface temperature changes. We test these assumptions using three boreholes in northwestern Utah that have been repeatedly logged for temperature over a time span of 29 years. We report 13 temperature-depth logs at the Emigrant Pass Observatory borehole GC-1, eight at borehole SI-1 and five at borehole DM-1, acquired between 1978 and 2007. Systematic subsurface temperature changes of up to 0.6°C are observed over this time span in the upper sections of the boreholes; below approximately 100 m any temperature transients are within observational noise. We difference the temperature logs to highlight subsurface transients and to remove any ambiguity resulting from steady state source of curvature. Synthetic temperature profiles computed from SAT data at nearby meteorological stations reproduce both the amplitude and pattern of the transient temperature observations, fitting the observations to within 0.03°C or better. This observational confirmation of the strong coupling between surface temperature change and borehole temperature transients lends further support to the use of borehole temperatures to complement SAT and multiproxy reconstructions of climate change.

  10. Sudden change of geometric quantum discord in finite temperature reservoirs

    SciTech Connect

    Hu, Ming-Liang Sun, Jian

    2015-03-15

    We investigate sudden change (SC) behaviors of the distance-based measures of geometric quantum discords (GQDs) for two non-interacting qubits subject to the two-sided and the one-sided thermal reservoirs. We found that the GQDs defined by different distances exhibit different SCs, and thus the SCs are the combined result of the chosen discord measure and the property of a state. We also found that the thermal reservoir may generate states having different orderings related to different GQDs. These inherent differences of the GQDs reveal that they are incompatible in characterizing quantum correlations both quantitatively and qualitatively. - Highlights: • Comparable study of different distance-based geometric quantum discords. • Evolution of the geometric quantum discords in finite temperature reservoirs. • Different geometric quantum discords exhibit distinct sudden changes. • Nonunique states ordering imposed by different geometric quantum discords.

  11. Stress-induced core temperature changes in pigeons (Columba livia).

    PubMed

    Bittencourt, Myla de Aguiar; Melleu, Fernando Falkenburger; Marino-Neto, José

    2015-02-01

    Changes in body temperature are significant physiological consequences of stressful stimuli in mammals and birds. Pigeons (Columba livia) prosper in (potentially) stressful urban environments and are common subjects in neurobehavioral studies; however, the thermal responses to stress stimuli by pigeons are poorly known. Here, we describe acute changes in the telemetrically recorded celomatic (core) temperature (Tc) in pigeons given a variety of potentially stressful stimuli, including transfer to a novel cage (ExC) leading to visual isolation from conspecifics, the presence of the experimenter (ExpR), gentle handling (H), sham intracelomatic injections (SI), and the induction of the tonic immobility (TI) response. Transfer to the ExC cage provoked short-lived hyperthermia (10-20 min) followed by a long-lasting and substantial decrease in Tc, which returned to baseline levels 2 h after the start of the test. After a 2-hour stay in the ExC, the other potentially stressful stimuli evoked only weak, marginally significant hyperthermic (ExpR, IT) or hypothermic (SI) responses. Stimuli delivered 26 h after transfer to the ExC induced definite and intense increases in Tc (ExpR, H) or hypothermic responses (SI). These Tc changes appear to be unrelated to modifications in general activity (as measured via telemetrically recorded actimetric data). Repeated testing failed to affect the hypothermic responses to the transference to the ExC, even after nine trials and at 1- or 8-day intervals, suggesting that the social (visual) isolation from conspecifics may be a strong and poorly controllable stimulus in this species. The present data indicated that stress-induced changes in Tc may be a consistent and reliable physiological parameter of stress but that they may also show stressor type-, direction- and species-specific attributes. PMID:25479572

  12. Sensitivity of Local Temperature CDFs to Global Climate Change

    NASA Astrophysics Data System (ADS)

    Stainforth, D.; Chapman, S. C.; Watkins, N. W.

    2011-12-01

    The sensitivity of climate to increasing atmospheric greenhouse gases at the global scale has been much studied [Knutti and Hegerl 2008, and references therein]. Scientific information to support climate change adaptation activities, however, is often sought at regional or local scales; the scales on which most adaptation decisions are made. Information on these scales is most often based on simulations of complex climate models [Murphy et al. 2009, Tebaldi et al. 2005] and have questionable reliability [Stainforth et al., 2007]. Rather than using data derived or obtained from models we focus on observational timeseries to evaluate the sensitivity of different parts of the local climatic distribution. Such an approach has many advantages: it avoids issues relating to model imperfections [Stainforth et al. 2007], it can be focused on decision relevant thresholds [e.g. Porter and Semenov, 2005], and it inherently integrates information relating to local climatic influences. Taking a timeseries of local daily temperatures for various locations across the United Kingdom we extract the changing cumulative distribution functions over time. We present a simple mathematical deconstruction of how two different observations from two different time periods can be assigned to the combination of natural variability and/or the consequences of climate change. Using this deconstruction we analyse the changing shape of the distributions and thus the sensitivity of different quartiles of the distribution. These sensitivities are found to be both regionally consistent and geographically varying across the United Kingdom; as one would expect given the different influences on local climate between, say, Western Scotland and South East England. We nevertheless find a common pattern of increased sensitivity in the 60th to 80th percentiles; above the mean but below the greatest extremes. The method has the potential to be applied to many other variables in addition to temperature and to

  13. A new approach to quantifying soil temperature responses to changing air temperature and snow cover

    NASA Astrophysics Data System (ADS)

    Mackiewicz, Michael C.

    2012-08-01

    Seasonal snow cover provides an effective insulating barrier, separating shallow soil (0.25 m) from direct localized meteorological conditions. The effectiveness of this barrier is evident in a lag in the soil temperature response to changing air temperature. The causal relationship between air and soil temperatures is largely because of the presence or absence of snow cover, and is frequently characterized using linear regression analysis. However, the magnitude of the dampening effect of snow cover on the temperature response in shallow soils is obscured in linear regressions. In this study the author used multiple linear regression (MLR) with dummy predictor variables to quantify the degree of dampening between air and shallow soil temperatures in the presence and absence of snow cover at four Greenland sites. The dummy variables defining snow cover conditions were z = 0 for the absence of snow and z = 1 for the presence of snow cover. The MLR was reduced to two simple linear equations that were analyzed relative to z = 0 and z = 1 to enable validation of the selected equations. Compared with ordinary linear regression of the datasets, the MLR analysis yielded stronger coefficients of multiple determination and less variation in the estimated regression variables.

  14. Cholera toxin effects on body temperature changes induced by morphine.

    PubMed

    Basilico, L; Parenti, M; Fumagalli, A; Parolaro, D; Giagnoni, G

    1997-03-01

    The present study evaluates the influence of cholera toxin and its B-subunit on thermic responses to morphine in the rats. The holotoxin (1 microg/rat) and the B-subunit (5 microg) were administered ICV and three days later rats were challenged ICV with morphine and tested for changes of body temperature. Cholera toxin, but not its B-subunit, modified the time course of the hyperthermic response induced by a low dose of morphine (2.5 microg), converted the hypothermia due to a higher dose of morphine (18 microg) to a consistent hyperthermia and only partially reduced the greater hypothermia induced by 36 microg of morphine. Cholera toxin-induced modifications of thermic responses to morphine were paralleled with a decreased Gs(alpha) immunoreactivity and a reduced ability for the toxin to catalyse the "in vitro" ADP-ribosylation of Gs(alpha) in hypothalamic membranes. In contrast, at the same time when morphine-induced effects on body temperature were assessed, no changes in pertussis toxin-mediated ADP-ribosylation of Gi(alpha)/Go(alpha), or basal adenylate cyclase activity, or binding of mu-opioid receptor selective ligand [3H]-DAMGO were observed in hypothalamic areas from rats treated with cholera toxin. These findings suggest that adaptative events secondary to prolonged activation of Gs(alpha) play a role in the modifications of thermic responses to morphine induced by CTX. PMID:9077589

  15. Changes in temperature and precipitation extremes observed in Modena, Italy

    NASA Astrophysics Data System (ADS)

    Boccolari, M.; Malmusi, S.

    2013-03-01

    Climate changes has become one of the most analysed subjects from researchers community, mainly because of the numerous extreme events that hit the globe. To have a better view of climate changes and trends, long observations time series are needed. During last decade a lot of Italian time series, concerning several surface meteorological variables, have been analysed and published. No one of them includes one of the longest record in Italy, the time series of the Geophysical Observatory of the University of Modena and Reggio Emilia. Measurements, collected since early 19th century, always in the same position, except for some months during the second world war, embrace daily temperature, precipitation amount, relative humidity, pressure, cloudiness and other variables. In this work we concentrated on the analysis of yearly and seasonal trends and climate extremes of temperature, both minimum and maximum, and precipitation time series, for the periods 1861-2010 and 1831-2010 respectively, in which continuous measurements are available. In general, our results confirm quite well those reported by IPCC and in many other studies over Mediterranean area. In particular, we found that minimum temperature has a non significant positive trend of + 0.1 °C per decade considering all the period, the value increases to 0.9 °C per decade for 1981-2010. For maximum temperature we observed a non significant + 0.1 °C trend for all the period, while + 0.8 °C for the last thirty years. On the other hand precipitation is decreasing, -6.3 mm per decade, considering all the analysed period, while the last thirty years are characterised by a great increment of 74.8 mm per decade. For both variables several climate indices have been analysed and they confirm what has been found for minimum and maximum temperatures and precipitation. In particular, during last 30 years frost days and ice days are decreasing, whereas summer days are increasing. During the last 30-year tropical nights

  16. Dangerous Near-Earth Asteroids and Meteorites

    NASA Astrophysics Data System (ADS)

    Mickaelian, A. M.; Grigoryan, A. E.

    2015-07-01

    The problem of Near-Earth Objects (NEOs; Astreoids and Meteorites) is discussed. To have an understanding on the probablity of encounters with such objects, one may use two different approaches: 1) historical, based on the statistics of existing large meteorite craters on the Earth, estimation of the source meteorites size and the age of these craters to derive the frequency of encounters with a given size of meteorites and 2) astronomical, based on the study and cataloging of all medium-size and large bodies in the Earth's neighbourhood and their orbits to estimate the probability, angles and other parameters of encounters. Therefore, we discuss both aspects and give our present knowledge on both phenomena. Though dangerous NEOs are one of the main source for cosmic catastrophes, we also focus on other possible dangers, such as even slight changes of Solar irradiance or Earth's orbit, change of Moon's impact on Earth, Solar flares or other manifestations of Solar activity, transit of comets (with impact on Earth's atmosphere), global climate change, dilution of Earth's atmosphere, damage of ozone layer, explosion of nearby Supernovae, and even an attack by extraterrestrial intelligence.

  17. Low temperature induced changes in gene expression in low temperature-sensitive and -tolerant tomatoes

    SciTech Connect

    Vallejos, C.E.; Camp, S.F. )

    1989-04-01

    The objective of this project is to identify genes that control low temperature (LT) tolerance/acclimation in a high altitude ecotype of the wild tomato L. hirsutum. LT induced changes in gene expression were monitored via 2-D gel electrophoresis and fluorography of radiolabeled in vitro translation products. Two types of changes were detected when both LT-sensitive (L. esculentum, L. hirsutum 100m) and LT-tolerant (L. hirsutum 3100m) genotypes were exposed to 6{degrees}C for 12 h in the dark: (a) specific LT induction or up-regulation or up-regulation of some genes; and (b) changes in the turnover rate of day specific mRNA's. Increased exposure lead to the disappearance of some mRNA's. These comparisons will lead to the identification of mRNA's involved in acclimation, and those involved in stress response.

  18. Rice and Climate Change: Danger, or Opportunity?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Carbon dioxide (CO2), the principle gas associated with global warming, is also one of four resources needed for plants to complete their life cycle (i.e. water, light, nutrients, CO2). The ongoing increase in its concentration may allow rice breeders to begin selecting for optimal varieties among ...

  19. Perceiving object dangerousness: an escape from pain?

    PubMed

    Anelli, Filomena; Ranzini, Mariagrazia; Nicoletti, Roberto; Borghi, Anna M

    2013-08-01

    A variety of studies showed that participants are facilitated when responding to graspable objects, while it has not been fully investigated what happens during interactions with graspable objects that are potentially dangerous. The present study focuses on the mechanisms underlying the processing of dangerous objects. In two experiments, we adopted a paradigm that has never been employed in this context, a bisection task. The line was flanked by objects belonging to different categories. We explored the sensitivity to the distinction between neutral and dangerous objects, by measuring whether the performance was biased toward a specific object category. In Experiment 1 both teenagers and adults bisected lines flanked by dangerous and neutral graspable objects, and they misperceived the line midpoint toward the neutral graspable object or, stated differently, on the opposite side of the dangerous graspable object. In Experiment 2 adults bisected lines flanked by dangerous and neutral objects matched on graspability (both graspable and ungraspable, Experiment 2a), or by graspable and ungraspable objects matched on dangerousness (both neutral and dangerous, Experiment 2b). Results confirmed the finding of Experiment 1, but also indicated that participants misperceived the line midpoint toward the ungraspable object when it was presented, being it dangerous or not. This evidence demonstrated sensitivity to object dangerousness maintained across lifespan. The emergence of aversive affordances evoked by dangerous graspable objects strenghtens the importance to consider graspability in the investigation of dangerous objects. Possible neural mechanisms involved in the processing of dangerous graspable objects are discussed. PMID:23743714

  20. Projected changes in precipitation extremes linked to temperature over Japan

    NASA Astrophysics Data System (ADS)

    Nayak, S.; Dairaku, K.; Takayabu, I.; Suzuki-Parker, A.

    2015-12-01

    Recent studies have argued that the extreme precipitation intensities are increasing in many regions across the globe due to atmospheric warming. This argument is based on the principle of Clausius-Clapeyron relationship which states that the atmosphere can hold more moisture in warmer air temperature (~7%/°C). In our study, we have investigated the precipitation extremes linked to temperature in current climate (1981-2000) and their projected changes in late 21st century (2081-2100, RCP4.5) over Japan from multi-model ensemble downscaling experiments by three RCMs (NHRCM, NRAMS, WRF) forced by JRA25 as well as three GCMs (CCSM4, MIROC5, MRI-GCM3). To do this, the precipitation intensities of wet days (defined as ≥ 0.05 mm/d) are stratified to different bins with 1°C temperature interval. We have also identified the occurrences of precipitation extremes in different spell durations and associated peak intensities exceeding various thresholds in two climate periods. We found that extreme precipitation intensities are increased by 5 mm/d in future climate for temperatures above 21°C (Fig. 1). Precipitation extremes of higher percentiles are projected to have larger increase rates in future climate scenarios (3-5%/°C in the current climate and 4-6%/°C in the future climate scenarios). The joint probability distribution of wet hours (≥1mm/h) with various peak intensities under future climate scenarios (RCP4.5) of the late 21st century suggests an increase of long-lived (>10hr) and short-lived (1-2hr) events. On the other hand, a relatively decrease of medium-lived events (3-10hr) are noticed in future climate scenario. The increase of extreme precipitation intensities in future climate is due to the increase in temperature under RCP4.5 (~2°C). Increase in temperature causes more evapotranspiration and subsequently increases the water vapor in the atmosphere.

  1. Surface roughness change on sandstone induced by temperature increase

    NASA Astrophysics Data System (ADS)

    Vlcko, J.; Kompanikova, Z.; Gomez-Heras, M.; Greif, V.; Durmekova, T.; Brcek, M.

    2012-04-01

    Optical surface profilometer allows capturing the information necessary to provide 3D surface measurements in a single image acquisition with a vertical micrometric resolution. The surface topography can be used for analyses, such as roughness evaluation. In this research, roughness changes of two types of sandstone samples were studied before and after heating to 60, 200, 400, 600 and 800 °C. Measurements obtained were converted into 3D 5 mm x 5 mm (25 mm2) topographic maps with a resolution of 2.5 µm. Surface roughness parameter Sq represents quantifies roughness from the maximum deviation along a mean surface and it is calculated as the root mean squared of five peaks and valleys of the specimen using Gaussian filter and 0.80 mm cut-off. The high spatial resolution obtained from visible-light optical surface profilometer is an ideal tool for observing rock surface alterations caused by decay factors. The authors present complete original process of surface roughness determination on rock samples adopting the portable profilometer using free accessible software packages. The different stability of the fabric of sandstones from Králiky and Oravská Jasenica after heating is due to their different mineral composition and different ratio of minerals that are more or less chemically stable at high temperatures, their resistance to thermal stress and other textural factors related to the distribution of grains and matrix. Percentage of minerals chemically stable at higher temperature, such as quartz, calcite, illite and muscovite, in fresh sandstone samples from Králiky is approximately 48%. Conversely, sandstones from Oravská Jasenica have significantly greater percentage of minerals stable at higher temperatures, such as quartz, albite, orthoclase, muscovite, illite and calcite than of other, less stable, minerals such as chlorite, biotite and kaolinite. Hence, percentage of minerals stable at higher temperatures was approximately 81 %. The results show how the

  2. Xylitol and Your Dog: Danger, Paws Off

    MedlinePlus

    ... Home For Consumers Consumer Updates Xylitol and Your Dog: Danger, Paws Off Share Tweet Linkedin Pin it ... back to top Why is Xylitol Dangerous to Dogs, but Not People? In both people and dogs, ...

  3. Long-term change in thermospheric temperature above Saint Santin

    NASA Astrophysics Data System (ADS)

    Donaldson, J. K.; Wellman, T. J.; Oliver, W. L.

    2010-11-01

    The 1966-1987 Saint Santin/Nançay incoherent scatter radar database is analyzed to determine long-term trends beyond those associated with the "natural" variations of solar and magnetic activity, season, and time of day. Trends averaging some -3 K/yr are found in the F region. Positive trends in the E region may be explained by the subsidence of an overlying warmer regime of air. The trend line seems to change slope around the "breakpoint" year 1979, with the cooling changing from -0.8 K/yr before that time to -5.5 K/yr afterward at 350 km altitude. These trends greatly exceed those predicted by model simulations for increases in greenhouse gas concentrations. Further, carbon dioxide shows no such breakpoint year, but ozone does, near the time of the change in thermospheric trend, and a surface climatic regime shift has also been reported near this time. It is not clear that greenhouse gases are driving the long-term trend in thermospheric temperature. Restriction of analysis to a particular time of day results in greatly different trends, from near zero at midnight to -6 K/yr at noon at 350 km altitude. A separate analysis to determine the long-term trend in the amplitude of the 24 h tide at 350 km altitude shows a large change, with the amplitude diminishing from 136 K in 1966 to 89 K in 1988. Our results show the great need to remove all other natural variations from long-term data sets in determining long-term trends to avoid great ambiguity in trend interpretation.

  4. Decadal Changes in the World's Coastal Latitudinal Temperature Gradients

    PubMed Central

    Baumann, Hannes; Doherty, Owen

    2013-01-01

    Most of the world's living marine resources inhabit coastal environments, where average thermal conditions change predictably with latitude. These coastal latitudinal temperature gradients (CLTG) coincide with important ecological clines,e.g., in marine species diversity or adaptive genetic variations, but how tightly thermal and ecological gradients are linked remains unclear. A first step is to consistently characterize the world's CLTGs. We extracted coastal cells from a global 1°×1° dataset of weekly sea surface temperatures (SST, 1982–2012) to quantify spatial and temporal variability of the world's 11 major CLTGs. Gradient strength, i.e., the slope of the linear mean-SST/latitude relationship, varied 3-fold between the steepest (North-American Atlantic and Asian Pacific gradients: −0.91°C and −0.68°C lat−1, respectively) and weakest CLTGs (African Indian Ocean and the South- and North-American Pacific gradients: −0.28, −0.29, −0.32°C lat−1, respectively). Analyzing CLTG strength by year revealed that seven gradients have weakened by 3–10% over the past three decades due to increased warming at high compared to low latitudes. Almost the entire South-American Pacific gradient (6–47°S), however, has considerably cooled over the study period (−0.3 to −1.7°C, 31 years), and the substantial weakening of the North-American Atlantic gradient (−10%) was due to warming at high latitudes (42–60°N, +0.8 to +1.6°C,31 years) and significant mid-latitude cooling (Florida to Cape Hatteras 26–35°N, −0.5 to −2.2°C, 31 years). Average SST trends rarely resulted from uniform shifts throughout the year; instead individual seasonal warming or cooling patterns elicited the observed changes in annual means. This is consistent with our finding of increased seasonality (i.e., summer-winter SST amplitude) in three quarters of all coastal cells (331 of 433). Our study highlights the regionally variable footprint of global climate change

  5. 30 CFR 57.12021 - Danger signs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Danger signs. 57.12021 Section 57.12021 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Underground § 57.12021 Danger signs. Suitable danger signs shall be posted at all major...

  6. 30 CFR 57.12021 - Danger signs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Danger signs. 57.12021 Section 57.12021 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Underground § 57.12021 Danger signs. Suitable danger signs shall be posted at all major...

  7. 30 CFR 57.12021 - Danger signs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Danger signs. 57.12021 Section 57.12021 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Underground § 57.12021 Danger signs. Suitable danger signs shall be posted at all major...

  8. 30 CFR 57.12021 - Danger signs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Danger signs. 57.12021 Section 57.12021 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Underground § 57.12021 Danger signs. Suitable danger signs shall be posted at all major...

  9. 30 CFR 57.12021 - Danger signs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Danger signs. 57.12021 Section 57.12021 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Underground § 57.12021 Danger signs. Suitable danger signs shall be posted at all major...

  10. Change In Minimum Temperature As A Response To Land Cover Change In South Florida

    NASA Astrophysics Data System (ADS)

    Kandel, H. P.; Melesse, A. M.

    2012-12-01

    Replacement of higher evapotranspirative surface materials such as water and vegetation cover by other materials such as buildings, roads, and pavements increases the Bowen's ratio from about 0.5-2.0 in rural to about ≈ 5.0 in urban areas resulting in higher surface and near surface atmospheric temperatures in the urban areas (Taha, 1997). This effect is intensified by low emissivity surfaces of the urban covers storing more heat energy during day time, but emitting less during night compared to the energy emitted by rural covers causing higher night time temperatures in urban centers, an effect called Urban Heat Island (UHI). South Florida has undergone tremendous land cover change from its pre-drainage vegetated and wetlands to post drainage agricultural and urban lands, especially after late 20th century. The objective of this study was to simultaneously analyze the land use/ land cover change and the rural/ urban minimum temperatures in south Florida for the period representing pre and post drainage states. The result shows urban sprawl increased from 8% at the beginning of the analysis period to about 14% at the end. Green vegetated areas, shrubs, and forests are found to be declined. The minimum temperature is found increased as maximum as 2°F in the urbanized stations, which remained constant or shows negligible increase in rural stations. The study dictates further micro level scrutiny in order to reach a conclusion on the development of UHI in south Florida. Key words: Bowen's ratio, emissivity, urban heat island

  11. Global Changes in the Sea Ice Cover and Associated Surface Temperature Changes

    NASA Astrophysics Data System (ADS)

    Comiso, Josefino C.

    2016-06-01

    The trends in the sea ice cover in the two hemispheres have been observed to be asymmetric with the rate of change in the Arctic being negative at -3.8 % per decade while that of the Antarctic is positive at 1.7 % per decade. These observations are confirmed in this study through analyses of a more robust data set that has been enhanced for better consistency and updated for improved statistics. With reports of anthropogenic global warming such phenomenon appears physically counter intuitive but trend studies of surface temperature over the same time period show the occurrence of a similar asymmetry. Satellite surface temperature data show that while global warming is strong and dominant in the Arctic, it is relatively minor in the Antarctic with the trends in sea ice covered areas and surrounding ice free regions observed to be even negative. A strong correlation of ice extent with surface temperature is observed, especially during the growth season, and the observed trends in the sea ice cover are coherent with the trends in surface temperature. The trend of global averages of the ice cover is negative but modest and is consistent and compatible with the positive but modest trend in global surface temperature. A continuation of the trend would mean the disappearance of summer ice by the end of the century but modelling projections indicate that the summer ice could be salvaged if anthropogenic greenhouse gases in the atmosphere are kept constant at the current level.

  12. A linear regression model for predicting PNW estuarine temperatures in a changing climate

    EPA Science Inventory

    Pacific Northwest coastal regions, estuaries, and associated ecosystems are vulnerable to the potential effects of climate change, especially to changes in nearshore water temperature. While predictive climate models simulate future air temperatures, no such projections exist for...

  13. Simulated Climate Change Effects of Snowpack Manipulations on Soil Temperature and Moisture in the Sierra Nevada Mountains

    NASA Astrophysics Data System (ADS)

    Johnson, B. G.; Jasoni, R. L.; Arnone, J.

    2012-12-01

    Future changes in climate are predicted to significantly affect the type and amount of precipitation in the Sierra Nevada Mountains of California and Nevada. Because most of the yearly precipitation in this region falls as snow, changes in snowfall amount, snowfall timing, and duration of the snowpack may dramatically affect the timing and persistence of soil temperature and moisture, and biological processes dependent on these soil factors. The objective of our study was to quantify the effects of manipulating snowpack amounts on soil temperature and moisture over a two year period, including both the addition and removal of snow in a Pinus jeffreii (Jeffrey Pine) forest located northeast of Lake Tahoe, Nevada. Soil temperatures measured during the first winter (above average snow year) remained higher in control plots when snow was present, and in snow-addition plots, than in snow-removal plots. However, these effects did not persist in the second year when total snowfall amounted to only 20% of that occurring in the first year. Surprisingly, the effects on soil moisture persisted through the summer of year two with soil VWC in snow removal plots averaging approximately 50% drier than the snow addition plots (6.5% average VWC in snow removal and 13.2% in snow addition plots) and 13% drier on average than the control plots (7.5% average VWC in control plots).These results suggest the possibility of prolonged reductions in soil moisture, soil microbial activity, plant growth, and even increased danger of wildfires if anthropogenic climate change reduces snowfall amount and snowpack duration.

  14. Pretest Caluculations of Temperature Changes for Field Thermal Conductivity Tests

    SciTech Connect

    N.S. Brodsky

    2002-07-17

    A large volume fraction of the potential monitored geologic repository at Yucca Mountain may reside in the Tptpll (Tertiary, Paintbrush Group, Topopah Spring Tuff, crystal poor, lower lithophysal) lithostratigraphic unit. This unit is characterized by voids, or lithophysae, which range in size from centimeters to meters. A series of thermal conductivity field tests are planned in the Enhanced Characterization of the Repository Block (ECRB) Cross Drift. The objective of the pretest calculation described in this document is to predict changes in temperatures in the surrounding rock for these tests for a given heater power and a set of thermal transport properties. The calculation can be extended, as described in this document, to obtain thermal conductivity, thermal capacitance (density x heat capacity, J {center_dot} m{sup -3} {center_dot} K{sup -1}), and thermal diffusivity from the field data. The work has been conducted under the ''Technical Work Plan For: Testing and Monitoring'' (BSC 2001). One of the outcomes of this analysis is to determine the initial output of the heater. This heater output must be sufficiently high that it will provide results in a reasonably short period of time (within several weeks or a month) and be sufficiently high that the heat increase is detectable by the instruments employed in the test. The test will be conducted in stages and heater output will be step increased as the test progresses. If the initial temperature is set too high, the experiment will not have as many steps and thus fewer thermal conductivity data points will result.

  15. Visual Aid to Demonstrate Change of State and Gas Pressure with Temperature

    ERIC Educational Resources Information Center

    Ghaffari, Shahrokh

    2011-01-01

    Demonstrations are used in chemistry lectures to improve conceptual understanding by direct observation. The visual aid described here is designed to demonstrate the change in state of matter with the change of temperature and the change of pressure with temperature. Temperature is presented by the rate of airflow and pressure is presented by…

  16. Response of California temperature to regional anthropogenic aerosol changes

    SciTech Connect

    Kirchstetter, Thomas; Novakov, T.; Kirchstetter, T.W.; Menon, S.; Aguiar, J.

    2008-05-12

    In this paper, we compare constructed records of concentrations of black carbon (BC)--an indicator of anthropogenic aerosols--with observed surface temperature trends in California. Annual average BC concentrations in major air basins in California significantly decreased after about 1990, coincident with an observed statewide surface temperature increase. Seasonal aerosol concentration trends are consistent with observed seasonal temperature trends. These data suggest that the reduction in anthropogenic aerosol concentrations contributed to the observed surface temperature increase. Conversely, high aerosol concentrations may lower surface temperature and partially offset the temperature increase of greenhouse gases.

  17. Atmospheric temperature changes over the 20th century at very high elevations in the European Alps from englacial temperatures

    NASA Astrophysics Data System (ADS)

    Gilbert, A.; Vincent, C.

    2013-05-01

    the paucity of observations, a great deal of uncertainty remains concerning temperature changes at very high altitudes over the last century. Englacial temperature measurements performed in boreholes provide a very good indicator of atmospheric temperatures for very high elevations although they are not directly related to air temperatures. Temperature profiles from seven deep boreholes drilled at three different sites between 4240 and 4300 m above sea level in the Mont Blanc area (French Alps) have been analyzed using a heat flow model and a Bayesian inverse modeling approach. Atmospheric temperature changes over the last century were estimated by simultaneous inversion of these temperature profiles. A mean warming rate of 0.14°C/decade between 1900 and 2004 was found. This is similar to the observed regional low altitude trend in the northwestern Alps, suggesting that air temperature trends are not altitude dependent.

  18. Dangerousness and mental health policy.

    PubMed

    Hewitt, J L

    2008-04-01

    Mental health policy development in the UK has become increasingly dominated by the assumed need to prevent violence and alleviate public concerns about the dangers of the mentally ill living in the community. Risk management has become the expected focus of contemporary mental health services, and responsibility has increasingly been devolved to individual service professionals when systems fail to prevent violence. This paper analyses the development of mental health legislation and its impact on services users and mental health professionals at the micro level of service delivery. Historical precedence, media influence and public opinion are explored, and the reification of risk is questioned in practical and ethical terms. The government's newest proposals for compulsory treatment in the community are discussed in terms of practical efficacy and therapeutic impact. Dangerousness is far from being an objectively observable phenomenon arising from clinical pathology, but is a formulation of what is partially knowable through social analysis and unknowable by virtue of its situation in individual psychic motivation. Risk assessment can therefore never be completely accurate, and the solution of a 'better safe than sorry' approach to mental health policy is ethically and pragmatically flawed. PMID:18307647

  19. A study on the measurement of the core body temperature change after radiofrequency ablation (RFA) through MR temperature mapping

    NASA Astrophysics Data System (ADS)

    Kim, Chang-Bok; Dong, Kyung-Rae; Yu, Young; Chung, Woon-Kwan; Cho, Jae-Hwan; Joo, Kyu-Ji

    2013-09-01

    This study examined the change in the heat generated during radiofrequency ablation (RFA) using a self-manufactured phantom and used magnetic resonance imaging (MRI) to analyze the change in the temperature of the core body and the tissues surrounding the phantom. In this experiment, the image and the phase image were obtained simultaneously from a gradient echo-based sequence using 1.5-Tesla MRI equipment and a 12-channel head coil. The temperature mapping technique was used to calculate the change in temperature. The regions of interest (ROIs) (ROI 1 - ROI 6) were set with a focus on the area where the RFA was performed, according to the temperature distribution, before monitoring the temperature change for one hour in time intervals of five minutes. The results showed that the temperature change in the ROI with time was largest in the ROI 1 and smallest in the ROI 5. In addition, after the RFA procedure, the temperature decreased from the initial value to 0 °C in one hour. The temperature changes in the core body and the surrounding tissues were confirmed by MRI temperature mapping, which is a noninvasive method.

  20. Dangerous people or dangerous situations? Some further thoughts.

    PubMed

    Prins, H

    1991-01-01

    The author enlarges upon and develops some observations upon the assessment of dangerousness which appeared in this journal a decade ago. In the present contribution, particular attention is paid to identifying the type of person at risk of committing further acts of serious personal harm to persons and or property and to the factors or circumstances that may be conducive to this. Finally, the author puts forward some views on why cues and clues may be missed and how these omissions might be overcome. 'Between the acting of a dreadful thing And the first motion, all the interim is Like a phantasma, or a hideous dream' Julius Caesar, Act II Scene 1. PMID:2005765

  1. Volume and density changes of biological fluids with temperature

    NASA Technical Reports Server (NTRS)

    Hinghofer-Szalkay, H.

    1985-01-01

    The thermal expansion of human blood, plasma, ultrafiltrate, and erythrocycte concentration at temperatures in the range of 4-48 C is studied. The mechanical oscillator technique which has an accuracy of 1 x 10 to the -5 th g/ml is utilized to measure fluid density. The relationship between thermal expansion, density, and temperature is analyzed. The study reveals that: (1) thermal expansion increases with increasing temperature; (2) the magnitude of the increase declines with increasing temperature; (3) thermal expansion increases with density at temperatures below 40 C; and (4) the thermal expansion of intracellular fluid is greater than that of extracellular fluid in the temperature range of 4-10 C, but it is equal at temperatures greater than or equal to 40 C.

  2. Seasonal Change Detection and Attribution of Surface Temperature changes over Interior Peninsular Region of India

    NASA Astrophysics Data System (ADS)

    Pattanayak, Sonali; Nagesh Kumar, Dasika

    2015-04-01

    A good number of studies have investigated recent trends in the observed and simulated hydrometeorological variables across the world. It has been challenging for the research community to address whether the significant change in climate over the course of 2nd half of 20th century is caused either due to natural or manmade effects. Although evidences for an anthropogenic contribution to climatic trends have been accumulated rapidly worldwide, for India these are scarce. Hence the formal efforts have been undertaken to distinguish whether the recent changes in seasonal temperature over India occurred due to natural internal variation of climate system or human influence using rigorous detection and attribution (D&A) procedure. The surface temperature is the most widely cited indicator of climate fluctuation. Hence maximum and minimum temperatures (Tmax & Tmin) which are among the six most commonly used variables for impact assessment studies are analyzed here. Seasonal divisions are based on conventional meteorological seasons: January-February (winter); March-May (pre monsoon); June-September (monsoon); October-December (post monsoon). Time span considered for this study is 1950-2005. Climate Research Unit (Version 3.21) gridded monthly temperature datasets are considered as observed data. Initially TFPW-MK (Trend Free Pre Whitening Mann Kendall) test is used to search the significant trends in the four seasons over all India. Temporal change detection analysis in evapotranspiration (which is one of the key processes in hydrological cycle) is essential for progress in water resources planning and management. Hence along with Tmax and Tmin, potential evapotranspiration (PET) has also been analyzed for the similar conditions. Significant upward trends in Tmax, Tmin and PET are observed over most of the grid points in Interior Peninsula (IP) region over India. Significant correlation was obtained between PET and Tmax compared to PET and Tmin. Trends in Tmin clearly

  3. Low Temperature Adaptation Is Not the Opposite Process of High Temperature Adaptation in Terms of Changes in Amino Acid Composition

    PubMed Central

    Yang, Ling-Ling; Tang, Shu-Kun; Huang, Ying; Zhi, Xiao-Yang

    2015-01-01

    Previous studies focused on psychrophilic adaptation generally have demonstrated that multiple mechanisms work together to increase protein flexibility and activity, as well as to decrease the thermostability of proteins. However, the relationship between high and low temperature adaptations remains unclear. To investigate this issue, we collected the available predicted whole proteome sequences of species with different optimal growth temperatures, and analyzed amino acid variations and substitutional asymmetry in pairs of homologous proteins from related species. We found that changes in amino acid composition associated with low temperature adaptation did not exhibit a coherent opposite trend when compared with changes in amino acid composition associated with high temperature adaptation. This result indicates that during their evolutionary histories the proteome-scale evolutionary patterns associated with prokaryotes exposed to low temperature environments were distinct from the proteome-scale evolutionary patterns associated with prokaryotes exposed to high temperature environments in terms of changes in amino acid composition of the proteins. PMID:26614525

  4. Soil erosion under climate change: simulatingthe response of temperature and rainfall changes in three UK catchments

    NASA Astrophysics Data System (ADS)

    Ciampalini, Rossano; Walker-Springett, Kate J.; Constantine, José Antonio; Hales, Tristram C.

    2015-04-01

    Soil erosion by water cost in environmental damages across the Great Britain is estimated in over £200m (2014 GBP) each year and could increase for the effect of climate change. Assessing the potential for increased climate-driven soil erosion, due to the several water processes involved (e.g., infiltration excess, return flow, direct precipitation onto saturated soil),is recognizedas a complex task. Climate change can have a positive and direct effect on soil erosionsuch the case of increasing rainfall in amount and intensity, or an indirect effect through the variation of the atmospheric CO2 level, which can improve plant productivityandwater infiltration capacity of soil reducing the likelihood of soil erosion. Changes in vegetation patterns and typologies with a different protection effect can lead also the soil system to dramatic changes in soil erosion rates, potentially amplifying or ameliorating the direct effects of climate change.Climate, vegetation and soil erosion are thus connected and several feedback effects could be accounted in the study of global change. Understanding these interactions may be a primary goal for clarifying the impact of global change on soil erosion and its consequences on related soil functions such as water and organic carbon storage support to vegetation and agricultural production. In this research, focused on three UK catchments (i.e. Conwy, 627 km2, Wales; Ehen, 225 km2, England; and Dee, 2100 km2, Scotland), we simulated soil erosionapplying SRES climatic scenarios(IPCC, 2000) for different CO2 emission levels. We modelled using Pesera "The Pan European Soil Erosion Risk Assessment" (Kirkby et al., 2004), a model for vegetation growing and soil erosion evaluation at regional scale. For each catchment,we realised a sensitivity - analysis - like test investigating different increments in temperature and rainfall, then, we compared the results of the SRES scenarios with the issues of the parametric sensitivity analysis. The

  5. Complex coupled metabolic and prokaryotic community responses to increasing temperatures in anaerobic marine sediments: critical temperatures and substrate changes.

    PubMed

    Roussel, Erwan G; Cragg, Barry A; Webster, Gordon; Sass, Henrik; Tang, Xiaohong; Williams, Angharad S; Gorra, Roberta; Weightman, Andrew J; Parkes, R John

    2015-08-01

    The impact of temperature (0-80°C) on anaerobic biogeochemical processes and prokaryotic communities in marine sediments (tidal flat) was investigated in slurries for up to 100 days. Temperature had a non-linear effect on biogeochemistry and prokaryotes with rapid changes over small temperature intervals. Some activities (e.g. methanogenesis) had multiple 'windows' within a large temperature range (∼10 to 80°C). Others, including acetate oxidation, had maximum activities within a temperature zone, which varied with electron acceptor [metal oxide (up to ∼34°C) and sulphate (up to ∼50°C)]. Substrates for sulphate reduction changed from predominantly acetate below, and H2 above, a 43°C critical temperature, along with changes in activation energies and types of sulphate-reducing Bacteria. Above ∼43°C, methylamine metabolism ceased with changes in methanogen types and increased acetate concentrations (>1 mM). Abundances of uncultured Archaea, characteristic of deep marine sediments (e.g. MBGD Euryarchaeota, 'Bathyarchaeota') changed, indicating their possible metabolic activity and temperature range. Bacterial cell numbers were consistently higher than archaeal cells and both decreased above ∼15°C. Substrate addition stimulated activities, widened some activity temperature ranges (methanogenesis) and increased bacterial (×10) more than archaeal cell numbers. Hence, additional organic matter input from climate-related eutrophication may amplify the impact of temperature increases on sedimentary biogeochemistry. PMID:26207045

  6. Complex coupled metabolic and prokaryotic community responses to increasing temperatures in anaerobic marine sediments: critical temperatures and substrate changes

    PubMed Central

    Roussel, Erwan G.; Cragg, Barry A.; Webster, Gordon; Sass, Henrik; Tang, Xiaohong; Williams, Angharad S.; Gorra, Roberta; Weightman, Andrew J.; Parkes, R. John

    2015-01-01

    The impact of temperature (0–80°C) on anaerobic biogeochemical processes and prokaryotic communities in marine sediments (tidal flat) was investigated in slurries for up to 100 days. Temperature had a non-linear effect on biogeochemistry and prokaryotes with rapid changes over small temperature intervals. Some activities (e.g. methanogenesis) had multiple ‘windows’ within a large temperature range (∼10 to 80°C). Others, including acetate oxidation, had maximum activities within a temperature zone, which varied with electron acceptor [metal oxide (up to ∼34°C) and sulphate (up to ∼50°C)]. Substrates for sulphate reduction changed from predominantly acetate below, and H2 above, a 43°C critical temperature, along with changes in activation energies and types of sulphate-reducing Bacteria. Above ∼43°C, methylamine metabolism ceased with changes in methanogen types and increased acetate concentrations (>1 mM). Abundances of uncultured Archaea, characteristic of deep marine sediments (e.g. MBGD Euryarchaeota, ‘Bathyarchaeota’) changed, indicating their possible metabolic activity and temperature range. Bacterial cell numbers were consistently higher than archaeal cells and both decreased above ∼15°C. Substrate addition stimulated activities, widened some activity temperature ranges (methanogenesis) and increased bacterial (×10) more than archaeal cell numbers. Hence, additional organic matter input from climate-related eutrophication may amplify the impact of temperature increases on sedimentary biogeochemistry. PMID:26207045

  7. The uncertainties of the net primary production due to regional and seasonal temperature changes in China

    NASA Astrophysics Data System (ADS)

    Sun, Guodong

    2015-04-01

    A kind of temperature change scenario is supplied by the approach of conditional nonlinear optimal perturbation related to parameter (CNOP-P) to estimate the variation of the net primary production (NPP)in North-South transect of eastern China within a state-of-the-art Lund-Potsdam-Jena dynamical global vegetation model (LPJ DGVM). There are two traits for the kind of temperature change scenario. Firstly, the kind of temperature change scenario considers the regional and seasonal differences in North-South transect of eastern China. The character of the temperature change is similar to the observation data due to the observational constraint. Secondly, the kind of temperature change scenario causes the maximal possible impact on the simulated NPP to discuss the maximal uncertainty in the simulated NPP to the temperature change in North-South transect of eastern China. Other two kinds of temperature change scenarios are also applied to explain the above two traits and to analyze variations due to different kinds of temperature change scenarios. It is shown that the kind of temperature change scenario resulted of the CNOP-P approach, which is called as the CNOP-P-type temperature change scenario, exhibits the regional and seasonal temperature differences in North-South transect of eastern China. The NPP decreases by 1.84% in northern China, and respectively increases by 4.09% and 18.99% in northeastern and southern China as the results of the CNOP-P-type temperature change scenario, though the NPP increases in small part of northern China and decreases in part of northeastern China. The variations in the NPP caused by the CNOP-P-type temperature change scenario are different to those by the other two types of temperature change scenarios in northern, northeastern China and southern China. The impact of the CNOP-P-type temperature change scenario on the NPP is intenser than that of the other two types of temperature change scenarios. The seasonal analyses demonstrate

  8. Personal Safety in Dangerous Places

    PubMed Central

    Williams, Terry; Dunlap, Eloise; Johnson, Bruce D.; Hamid, Ansley

    2009-01-01

    Personal safety during fieldwork is seldom addressed directly in the literature. Drawing from many prior years of ethnographic research and from field experience while studying crack distributors in New York City, the authors provide a variety of strategies by which ethnographic research can be safely conducted in dangerous settings. By projecting an appropriate demeanor, ethnographers can seek others for protector and locator roles, routinely create a safety zone in the field, and establish compatible field roles with potential subjects. The article also provides strategies for avoiding or handling sexual approaches, common law crimes, fights, drive-by shootings, and contacts with the police. When integrated with other standard qualitative methods, ethnographic strategies help to ensure that no physical harm comes to the field-worker and other staff members. Moreover, the presence of researchers may actually reduce (and not increase) potential and actual violence among crack distributors/abusers or others present in the field setting. PMID:19809525

  9. Assessing the Influence of Precipitation on Diurnal Temperature Range Changes: Implications for Climate Change Projection

    NASA Astrophysics Data System (ADS)

    Van den Hoof, C.; Garreaud, R.

    2014-12-01

    . Braganza, D.J. Karoly, and J.M. Arblaster. Diurnal temperature range as an index of global climate change during the twentieth century. Geophysical Research Letters, 31:1-4, 2004. [2] A. Dai, A.D. Del Genio, and I.Y. Fung. Clouds, precipitation and temperature range. Nature, 386:665-666, 1997.

  10. The danger theory: 20 years later.

    PubMed

    Pradeu, Thomas; Cooper, Edwin L

    2012-01-01

    The self-non-self theory has dominated immunology since the 1950s. In the 1990s, Matzinger and her colleagues suggested a new, competing theory, called the "danger theory." This theory has provoked mixed acclaim: enthusiasm and criticism. Here we assess the danger theory vis-à-vis recent experimental data on innate immunity, transplantation, cancers and tolerance to foreign entities, and try to elucidate more clearly whether danger is well defined. PMID:23060876

  11. The danger theory: 20 years later

    PubMed Central

    Pradeu, Thomas; Cooper, Edwin L.

    2012-01-01

    The self–non-self theory has dominated immunology since the 1950s. In the 1990s, Matzinger and her colleagues suggested a new, competing theory, called the “danger theory.” This theory has provoked mixed acclaim: enthusiasm and criticism. Here we assess the danger theory vis-à-vis recent experimental data on innate immunity, transplantation, cancers and tolerance to foreign entities, and try to elucidate more clearly whether danger is well defined. PMID:23060876

  12. Skin sites to predict deep-body temperature while wearing firefighters' personal protective equipment during periodical changes in air temperature.

    PubMed

    Kim, Siyeon; Lee, Joo-Young

    2016-04-01

    The aim of this study was to investigate stable and valid measurement sites of skin temperatures as a non-invasive variable to predict deep-body temperature while wearing firefighters' personal protective equipment (PPE) during air temperature changes. Eight male firefighters participated in an experiment which consisted of 60-min exercise and 10-min recovery while wearing PPE without self-contained breathing apparatus (7.75 kg in total PPE mass). Air temperature was periodically fluctuated from 29.5 to 35.5 °C with an amplitude of 6 °C. Rectal temperature was chosen as a deep-body temperature, and 12 skin temperatures were recorded. The results showed that the forehead and chest were identified as the most valid sites to predict rectal temperature (R(2) = 0.826 and 0.824, respectively) in an environment with periodically fluctuated air temperatures. This study suggests that particular skin temperatures are valid as a non-invasive variable when predicting rectal temperature of an individual wearing PPE in changing ambient temperatures. Practitioner Summary: This study should offer assistance for developing a more reliable indirect indicating system of individual heat strain for firefighters in real time, which can be used practically as a precaution of firefighters' heat-related illness and utilised along with physiological monitoring. PMID:26214379

  13. Corrosion fatigue behavior and life prediction method under changing temperature condition

    SciTech Connect

    Kanasaki, Hiroshi; Hirano, Akihiko; Iida, Kunihiro; Asada, Yasuhide

    1997-12-01

    Axially strain controlled low cycle fatigue tests of a carbon steel in oxygenated high temperature water were carried out under changing temperature conditions. Two patterns of triangular wave were selected for temperature cycling. One was in-phase pattern synchronizing with strain cycling and the other was an out-of-phase pattern in which temperature was changed in anti-phase to the strain cycling. The fatigue life under changing temperature condition was in the range of the fatigue life under various constant temperature within the range of the changing temperature. The fatigue life of in-phase pattern was equivalent to that of out-of-phase pattern. The corrosion fatigue life prediction method was proposed for changing temperature condition, and was based on the assumption that the fatigue damage increased in linear proportion to increment of strain during cycling. The fatigue life predicted by this method was in good agreement with the test results.

  14. Dangerous Spaces, Dangerous Memories, Dangerous Emotions: Informal Education and Heteronormativity--A Manchester UK Youth Work Vignette

    ERIC Educational Resources Information Center

    Batsleer, Janet

    2012-01-01

    This article makes a connection between youth work spaces, emotions and some elements of memory, exploring the construction of spaces dangerous for social justice in both meanings of the term "dangerous for". It investigates the contribution to social justice of lesbian and gay youth work and other non-heteronormative youth work in a British…

  15. Distributional changes in gene-specific methylation associated with temperature.

    PubMed

    Bind, Marie-Abele C; Coull, Brent A; Baccarelli, Andrea; Tarantini, Letizia; Cantone, Laura; Vokonas, Pantel; Schwartz, Joel

    2016-10-01

    Temperature has been related to mean differences in DNA methylation. However, heterogeneity in these associations may exist across the distribution of methylation outcomes. This study examined whether the association between three-week averaged of temperature and methylation differs across quantiles of the methylation distributions in nine candidate genes. We measured gene-specific blood methylation repeatedly in 777 elderly men participating in the Normative Aging Study (1999-2010). We fit quantile regressions for longitudinal data to investigate whether the associations of temperature on methylation (expressed as %5mC) varied across the distribution of the methylation outcomes. We observed heterogeneity in the associations of temperature across percentiles of methylation in F3, TLR-2, CRAT, iNOS, and ICAM-1 genes. For instance, an increase in three-week temperature exposure was associated with a longer left-tail of the F3 methylation distribution. A 5°C increase in temperature was associated with a 0.15%5mC (95% confidence interval (CI): -0.27,-0.04) decrease on the 20th quantile of F3 methylation, but was not significantly related to the 80th quantile of this distribution (Estimate:0.06%5mC, 95%CI: -0.22, 0.35). Individuals with low values of F3, TLR-2, CRAT, and iNOS methylation, as well as a high value of ICAM-1 methylation, may be more susceptible to temperature effects on systemic inflammation. PMID:27236570

  16. Global surface temperature changes since the 1850s

    SciTech Connect

    Jones, P.D.

    1996-12-31

    Temperature data from land and marine areas form the basis for many studies of climatic variations on local, regional and hemispheric scales, and the global mean temperature is a fundamental measure of the state of the climate system. In this paper it is shown that the surface temperature of the globe has warmed by about 0.5{degrees}C since the mid-nineteenth century. This is an important part of the evidence in the {open_quote}global warming{close_quote} debate. How certain are we about the magnitude of the warming? Where has it been greatest? In this paper, these and related issues will be addressed.

  17. Temperature changes across porcelain during multiple exposure CO2 lasing

    NASA Astrophysics Data System (ADS)

    Barron, Joseph R.; Zakariasen, Kenneth L.; Peacocke, Larry

    1990-06-01

    Research indicates that laser energy may provide a useful method for glazing and fusing porcelain for intraoral prosthetic purposes. However, it is not known whether such lasing will result in the production of heat levels that may be damaging to adjacent vital tissues such as the dental pulp and periodontal tissues. This research is designed to measure the magnitude of temperature rise across porcelain observed during multiple exposure C02 lasing. Fifteen porcelain examples of 1000 jim (5), 1500 pm (5) and 2000 tm (5) x each received five C02 laser exposures on the same exposure site at 1.0 sec. intervals at 8.0 watts (0.2 sec. per exposure with a 1 mm focal spot). A YSI 144201 thermilinear precision thermistor was placed on the porcelain surface opposite each laser exposure site. Temperature rise above ambient was recorded by an HP3421A data acquisition unit and HP9816 technical microcomputer. Recording continued for sufficient time to allow temperatures to return to ambient. The mean temperature elevations ranged from a low of 2.97 0C (2000 pm) to a high of 7.77 °C (1000 μm). ANOVA and Duncan's Multiple Range Test indicated significant differences in temperature rise by porcelain thickness. It would appear from the results of this research that temperature elevations adjacent to lased porcelain may be sufficiently controllable that safe intraoral porcelain lasing will be possible.

  18. Climate Change: A New Metric to Measure Changes in the Frequency of Extreme Temperatures using Record Data

    NASA Technical Reports Server (NTRS)

    Munasinghe, L.; Jun, T.; Rind, D. H.

    2012-01-01

    Consensus on global warming is the result of multiple and varying lines of evidence, and one key ramification is the increase in frequency of extreme climate events including record high temperatures. Here we develop a metric- called "record equivalent draws" (RED)-based on record high (low) temperature observations, and show that changes in RED approximate changes in the likelihood of extreme high (low) temperatures. Since we also show that this metric is independent of the specifics of the underlying temperature distributions, RED estimates can be aggregated across different climates to provide a genuinely global assessment of climate change. Using data on monthly average temperatures across the global landmass we find that the frequency of extreme high temperatures increased 10-fold between the first three decades of the last century (1900-1929) and the most recent decade (1999-2008). A more disaggregated analysis shows that the increase in frequency of extreme high temperatures is greater in the tropics than in higher latitudes, a pattern that is not indicated by changes in mean temperature. Our RED estimates also suggest concurrent increases in the frequency of both extreme high and extreme low temperatures during 2002-2008, a period when we observe a plateauing of global mean temperature. Using daily extreme temperature observations, we find that the frequency of extreme high temperatures is greater in the daily minimum temperature time-series compared to the daily maximum temperature time-series. There is no such observable difference in the frequency of extreme low temperatures between the daily minimum and daily maximum.

  19. 49 CFR 172.521 - DANGEROUS placard.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... area and 1/2-inch (12.7 mm.) border must be white. The inscription must be black with the 1/8-inch (3.2 mm.) border marker in the white area at each end of the inscription red. ... SECURITY PLANS Placarding § 172.521 DANGEROUS placard. (a) Except for size and color, the DANGEROUS...

  20. 49 CFR 172.521 - DANGEROUS placard.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... area and 1/2-inch (12.7 mm.) border must be white. The inscription must be black with the 1/8-inch (3.2 mm.) border marker in the white area at each end of the inscription red. ... SECURITY PLANS Placarding § 172.521 DANGEROUS placard. (a) Except for size and color, the DANGEROUS...

  1. The Dangers of Educated Girls and Women

    ERIC Educational Resources Information Center

    John, Vaughn M.

    2016-01-01

    Why do educated girls and women constitute a danger in some societies and for this face extreme danger in their educational endeavours? This article argues that historical and contemporary educational discrimination of girls and women is the hallmark of a violently patriarchal society, and this stubborn injustice is exacerbated under conditions of…

  2. 30 CFR 56.12021 - Danger signs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Danger signs. 56.12021 Section 56.12021 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12021 Danger...

  3. 30 CFR 56.12021 - Danger signs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Danger signs. 56.12021 Section 56.12021 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12021 Danger...

  4. 30 CFR 56.12021 - Danger signs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Danger signs. 56.12021 Section 56.12021 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12021 Danger...

  5. 30 CFR 56.12021 - Danger signs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Danger signs. 56.12021 Section 56.12021 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12021 Danger...

  6. 30 CFR 56.12021 - Danger signs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Danger signs. 56.12021 Section 56.12021 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12021 Danger...

  7. Tennessee Killing Underscores Job Dangers for Leaders

    ERIC Educational Resources Information Center

    Tonn, Jessica L.

    2005-01-01

    In this article, the author stresses the dangers facing school leaders on the job. The school shooting at Campbell County Comprehensive High School in Jacksboro, Tennessee, on November 8, 2005, which left one assistant principal dead and the principal and another assistant principal seriously wounded, is an extreme example of dangers school…

  8. Effect of climate change on water temperature and attainment of water temperature criteria in the Yaquina Estuary, Oregon (USA)

    NASA Astrophysics Data System (ADS)

    Brown, Cheryl A.; Sharp, Darrin; Mochon Collura, T. Chris

    2016-02-01

    There is increasing evidence that our planet is warming and this warming is also resulting in rising sea levels. Estuaries which are located at the interface between land and ocean are impacted by these changes. We used CE-QUAL-W2 water quality model to predict changes in water temperature as a function of increasing air temperatures and rising sea level for the Yaquina Estuary, Oregon (USA). Annual average air temperature in the Yaquina watershed is expected to increase about 0.3 °C per decade by 2040-2069. An air temperature increase of 3 °C in the Yaquina watershed is likely to result in estuarine water temperature increasing by 0.7-1.6 °C. Largest water temperature increases are expected in the upper portion of the estuary, while sea level rise may mitigate some of the warming in the lower portion of the estuary. Smallest changes in water temperature are predicted to occur in the summer, and maximum changes during the winter and spring. Increases in air temperature may result in an increase in the number of days per year that the 7-day maximum average temperature exceeds 18 °C (criterion for protection of rearing and migration of salmonids and trout) as well as other water quality concerns. In the upstream portion of the estuary, a 4 °C increase in air temperature is predicted to cause an increase of 40 days not meeting the temperature criterion, while in the lower estuary the increase will depend upon rate of sea level rise (ranging from 31 to 19 days).

  9. Trends and Patterns of Change in Temperature and Evaporation

    NASA Astrophysics Data System (ADS)

    Ragno, E.; AghaKouchak, A.

    2014-12-01

    Global mean monthly temperature has increased substantially in the past decades. On the other hand, there are contradictory reports on the response of the potential evaporation to a warming climate. In this study, ground based observations of temperature, and direct measurements of pan potential evaporation are evaluated across the United States. Furthermore, empirical simulations of the potential evaporation have been evaluated against observations. The results show that empirical (e.g., Thornthwaite method) estimates of the potential evapotranspiration show trends inconsistent with the ground-based observations. In fact, while temperature data show a significant upward trend across most of the United States, ground-based evaporation data in most locations do not exhibit a statistically significant trend. Empirical methods of potential evaporation estimation, including the Thornthwaite method, show trends similar to temperature. The primary reason is that many of the empirical approaches are dominated by temperature. Currently, empirical estimates of potential evaporation are widely used for numerous applications including water stress analysis. This indicates that using empirical estimates of potential estimation for irrigation water demand estimation and also drought assessment could lead to unrealistic results.

  10. [The temperature and temperature gradient distribution in the thermophysical model of the rabbit body subjected internal and external changes of temperature].

    PubMed

    Rumiantsev, G V

    2002-03-01

    In a laboratory heat-physical model of the rabbit reflecting basic heat-physical parameters of animal body (weight, heat absorption and heat production, size of a relative surface, capacity heat-production etc.), the changes of radial distribution of temperature and size of a cross superficial temperature gradient of the body were investigated with various parities (ratio) of environmental temperature and size of capacity heat production imitated by an electrical heater. Superficial layer of the body dependent from capacity heat production and environmental temperature can serve for definition of general heat content changes in the body for maintaining its thermal balance within the environment. PMID:12013736

  11. Dynamics of cell membrane permeability changes at supraphysiological temperatures.

    PubMed Central

    Bischof, J C; Padanilam, J; Holmes, W H; Ezzell, R M; Lee, R C; Tompkins, R G; Yarmush, M L; Toner, M

    1995-01-01

    A quantitative fluorescent microscopy system was developed to characterize, in real time, the effects of supraphysiological temperatures between 37 degrees and 70 degrees C on the plasma membrane of mouse 3T3 fibroblasts and isolated rat skeletal muscle cells. Membrane permeability was assessed by monitoring the leakage as a function of time of the fluorescent membrane integrity probe calcein. The kinetics of dye leakage increased with increasing temperature in both the 3T3 fibroblasts and the skeletal muscle cells. Analytical solutions derived from a two-compartment transport model showed that, for both cell types, a time-dependent permeability assumption provided a statistically better fit of the model predictions to the data than a constant permeability assumption. This finding suggests that the plasma membrane integrity is continuously being compromised while cells are subjected to supraphysiological temperatures. Images FIGURE 1 FIGURE 2 FIGURE 3 PMID:7647264

  12. A simplified physically-based model to calculate surface water temperature of lakes from air temperature in climate change scenarios

    NASA Astrophysics Data System (ADS)

    Piccolroaz, S.; Toffolon, M.

    2012-12-01

    Modifications of water temperature are crucial for the ecology of lakes, but long-term analyses are not usually able to provide reliable estimations. This is particularly true for climate change studies based on Global Circulation Models, whose mesh size is normally too coarse for explicitly including even some of the biggest lakes on Earth. On the other hand, modeled predictions of air temperature changes are more reliable, and long-term, high-resolution air temperature observational datasets are more available than water temperature measurements. For these reasons, air temperature series are often used to obtain some information about the surface temperature of water bodies. In order to do that, it is common to exploit regression models, but they are questionable especially when it is necessary to extrapolate current trends beyond maximum (or minimum) measured temperatures. Moreover, water temperature is influenced by a variety of processes of heat exchange across the lake surface and by the thermal inertia of the water mass, which also causes an annual hysteresis cycle between air and water temperatures that is hard to consider in regressions. In this work we propose a simplified, physically-based model for the estimation of the epilimnetic temperature in lakes. Starting from the zero-dimensional heat budget, we derive a simplified first-order differential equation for water temperature, primarily forced by a seasonally varying external term (mainly related to solar radiation) and an exchange term explicitly depending on the difference between air and water temperatures. Assuming annual sinusoidal cycles of the main heat flux components at the atmosphere-lake interface, eight parameters (some of them can be disregarded, though) are identified, which can be calibrated if two temporal series of air and water temperature are available. We note that such a calibration is supported by the physical interpretation of the parameters, which provide good initial

  13. Potential climate change effects on rice: Carbon dioxide and temperature

    SciTech Connect

    Baker, J.T.; Boote, K.J.; Allen, L.H. Jr. |

    1995-12-31

    The projected doubling of current levels of atmospheric CO{sub 2} concentration [CO{sub 2}] during the next century, along with increases in other radiatively active gases, has led to predictions of increases in global air temperature and shifts in precipitation patterns. Since 1987, several [CO{sub 2}] and temperature experiments have been conducted on rice (Oryza sativa L., cv. IR-30) in outdoor, naturally-sunlit, environmentally-controlled, plant growth chambers. The objectives of this chapter are to summarize some of the major findings of these experiments. In these experiments, season-long [CO{sub 2}] treatments ranged from 160 to 900 {micro}mol CO{sub 2} mol{sup {minus}1} air, while temperature treatments ranged from 25/18/21 to 40/33/37 C (daytime dry bulb air temperature/nighttime dry bulb air temperature/constant paddy water temperature). Total growth duration was shortened by 10 to 12 d as [CO{sub 2}] increased across a [CO{sub 2}] range from 160 to 500 {micro}mol mol{sup {minus}1}, due mainly to a shortened vegetative phase of development and a reduction in the number of mainstem leaves formed prior to panicle initiation. Photosynthesis, growth, and final grain yield increased with [CO{sub 2}] from 160 to 500 {micro}mol mol{sup {minus}1}, but were very similar from 500 to 900 {micro}mol mol{sup {minus}1}. Carbon dioxide enrichment from 330 to 660 {micro}mol mol{sup {minus}1} increased grain yield mainly by increasing the number of panicles per plant, and increasing temperature treatment above 28/21/25 C resulted in decreased grain yield, due largely to a decline in the number of filled grain per panicle. Evapotranspiration decreased and water-use efficiency increased with increasing [CO{sub 2}] treatment, while the reverse trends were found with increasing temperature treatment. 60 refs., 7 figs., 2 tabs.

  14. Assessing Climate Change: Temperatures, Solar Radiation and Heat Balance

    NASA Astrophysics Data System (ADS)

    Geller, Marvin

    2008-08-01

    The science of climate change is being investigated by thousands of scientists, is constantly in the news, and is discussed in the political arena worldwide. My Internet search on the words ``climate change'' produced about 40,600,000 hits. The 2007 Nobel Peace Prize was awarded to former U.S. vice president Al Gore and the United Nations' Intergovernmental Panel on Climate Change (IPCC). Of course, the subject goes beyond the science. The debate on what, if anything, should be done about humankind's influence on climate is the subject of U.S. and international political debate.

  15. Involvement of GABA in environmental temperature-induced change in body temperature.

    PubMed

    Biswas, S; Poddar, M K

    1988-12-01

    Acute exposure of adult male albino rats (110-120 g) to higher environmental temperature (40 +/- 1 degrees C) increased body temperature (BT). This increase of BT was also dependent on the duration of exposure. Treatment with muscimol (1 mg/kg, i.p.), a GABA agonist, produced hypothermia at room temperature (28 +/- 1 degree C) and resistance to increase the body temperature when exposed to higher temperature (40 +/- 1 degree C). Administration of bicuculline (1 mg/kg, i.p.), a GABA antagonist, on the other hand, enhanced BT more than that observed in control (normal) rat exposed to higher temperature (40 +/- 1 degree C), although at room temperature bicuculline treatment did not show any effect on BT. Pretreatment with ethanolamine-O-sulfate (EOS) (2 g/kg, s.c.), a GABA transaminase inhibitor, to rats exposed to higher temperature increased BT as in control (normal) rat. Inhibition of central GAD activity with mercaptopropionic acid (MPA) (70 mg/kg, i.p.) produced resistance to increase BT during its period of action when rats were exposed to higher environmental temperature (28 +/- 1 degree C). These results thus suggest that central inhibitory neuron, GABA, plays a regulatory role in thermoregulation. PMID:3236943

  16. Volcanic Contribution to Decadal Changes in Tropospheric Temperature

    NASA Technical Reports Server (NTRS)

    Santer, Benjamin D.; Bonfils, Celine; Painter, Jeffrey F.; Zelinka, Mark D.; Mears, Carl; Solomon, Susan; Schmidt, Gavin A.; Fyfe, John C.; Cole, Jason N.S.; Nazarenko, Larissa; Taylor, Karl E.; Wentz, Frank J.

    2014-01-01

    Despite continued growth in atmospheric levels of greenhouse gases, global mean surface and tropospheric temperatures have shown slower warming since 1998 than previously. Possible explanations for the slow-down include internal climate variability, external cooling influences and observational errors. Several recent modelling studies have examined the contribution of early twenty-first-century volcanic eruptions to the muted surface warming. Here we present a detailed analysis of the impact of recent volcanic forcing on tropospheric temperature, based on observations as well as climate model simulations. We identify statistically significant correlations between observations of stratospheric aerosol optical depth and satellite-based estimates of both tropospheric temperature and short-wave fluxes at the top of the atmosphere. We show that climate model simulations without the effects of early twenty-first-century volcanic eruptions overestimate the tropospheric warming observed since 1998. In two simulations with more realistic volcanic influences following the 1991 Pinatubo eruption, differences between simulated and observed tropospheric temperature trends over the period 1998 to 2012 are up to 15% smaller, with large uncertainties in the magnitude of the effect. To reduce these uncertainties, better observations of eruption-specific properties of volcanic aerosols are needed, as well as improved representation of these eruption-specific properties in climate model simulations.

  17. Instrument accurately measures small temperature changes on test surface

    NASA Technical Reports Server (NTRS)

    Harvey, W. D.; Miller, H. B.

    1966-01-01

    Calorimeter apparatus accurately measures very small temperature rises on a test surface subjected to aerodynamic heating. A continuous thin sheet of a sensing material is attached to a base support plate through which a series of holes of known diameter have been drilled for attaching thermocouples to the material.

  18. Water Temperature changes in the Mississippi River Basin

    EPA Science Inventory

    In this study, we demonstrate the transfer of a physically based semi-Lagrangian water temperature model (RBM) to EPA, its linkage with the Variable Infiltration Capacity (VIC) hydrology model, and its calibration to and demonstration for the Mississippi River Basin (MRB). The r...

  19. Changes in Population Occupancy of Bradyrhizobia under Diffrent Temperature Regimes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cultivation of Bradyrhizobium japonicum strains (USDA 6T, 38, and 123) and Bradyrhizobium elkanii strain (USDA 76T) were conducted to compare their respective proliferation traits under different cultivation temperature conditions with yeast-extract mannitol broth medium and to estimate the strain p...

  20. Spring temperature change and its implication in the change of vegetation growth in North America from 1982 to 2006

    PubMed Central

    Wang, Xuhui; Piao, Shilong; Ciais, Philippe; Li, Junsheng; Friedlingstein, Pierre; Koven, Charlie; Chen, Anping

    2011-01-01

    Understanding how vegetation growth responds to climate change is a critical requirement for projecting future ecosystem dynamics. Parts of North America (NA) have experienced a spring cooling trend over the last three decades, but little is known about the response of vegetation growth to this change. Using observed climate data and satellite-derived Normalized Difference Vegetation Index (NDVI) data from 1982 to 2006, we investigated changes in spring (April–May) temperature trends and their impact on vegetation growth in NA. A piecewise linear regression approach shows that the trend in spring temperature is not continuous through the 25-year period. In the northwestern region of NA, spring temperature increased until the late 1980s or early 1990s, and stalled or decreased afterwards. In response, a spring vegetation greening trend, which was evident in this region during the 1980s, stalled or reversed recently. Conversely, an opposite phenomenon occurred in the northeastern region of NA due to different spring temperature trends. Additionally, the trends of summer vegetation growth vary between the periods before and after the turning point (TP) of spring temperature trends. This change cannot be fully explained by summer drought stress change alone and is partly explained by changes in the trends of spring temperature as well as those of summer temperature. As reported in previous studies, summer vegetation browning trends have occurred in the northwestern region of NA since the early 1990s, which is consistent with the spring and summer cooling trends in this region during this period. PMID:21220297

  1. A closer look at temperature changes with remote sensing

    NASA Astrophysics Data System (ADS)

    Metz, Markus; Rocchini, Duccio; Neteler, Markus

    2014-05-01

    Temperature is a main driver for important ecological processes. Time series temperature data provide key environmental indicators for various applications and research fields. High spatial and temporal resolution is crucial in order to perform detailed analyses in various fields of research. While meteorological station data are commonly used, they often lack completeness or are not distributed in a representative way. Remotely sensed thermal images from polar orbiting satellites are considered to be a good alternative to the scarce meteorological data as they offer almost continuous coverage of the Earth with very high temporal resolution. A drawback of temperature data obtained by satellites is the occurrence of gaps (due to clouds, aerosols) that must be filled. We have reconstructed a seamless and gap-free time series for land surface temperature (LST) at continental scale for Europe from MODIS LST products (Moderate Resolution Imaging Sensor instruments onboard the Terra and Aqua satellites), keeping the temporal resolution of four records per day and enhancing the spatial resolution from 1 km to 250 m. Here we present a new procedure to reconstruct MODIS LST time series with unprecedented detail in space and time, at the same time providing continental coverage. Our method constitutes a unique new combination of weighted temporal averaging with statistical modeling and spatial interpolation. We selected as auxiliary variables datasets which are globally available in order to propose a worldwide reproducible method. Compared to existing similar datasets, the substantial quantitative difference translates to a qualitative difference in applications and results. We consider both our dataset and the new procedure for its creation to be of utmost interest to a broad interdisciplinary audience. Moreover, we provide examples for its implications and applications, such as disease risk assessment, epidemiology, environmental monitoring, and temperature anomalies. In

  2. Can air temperatures be used to project influences of climate change on stream temperatures?

    NASA Astrophysics Data System (ADS)

    Arismendi, I.; Safeeq, M.; Dunham, J.; Johnson, S. L.

    2013-12-01

    The lack of available in situ stream temperature records at broad spatiotemporal scales have been recognized as a major limiting factor in the understanding of thermal behavior of stream and river systems. This has motivated the promotion of a wide variety of models that use surrogates for stream temperatures including a regression approach that uses air temperature as the predictor variable. We investigate the long-term performance of widely used linear and non-linear regression models between air and stream temperatures to project the latter in future climate scenarios. Specifically, we examine the temporal variability of the parameters that define each of these models in long-term stream and air temperature datasets representing relatively natural and highly human-influenced streams. We selected 25 sites with long-term records that monitored year-round daily measurements of stream temperature (daily mean) in the western United States (California, Oregon, Idaho, Washington, and Alaska). Surface air temperature data from each site was not available. Therefore, we calculated daily mean surface air temperature for each site in contiguous US from a 1/16-degree resolution gridded surface temperature data. Our findings highlight several limitations that are endemic to linear or nonlinear regressions that have been applied in many recent attempts to project future stream temperatures based on air temperature. Our results also show that applications over longer time periods, as well as extrapolation of model predictions to project future stream temperatures are unlikely to be reliable. Although we did not analyze a broad range of stream types at a continental or global extent, our analysis of stream temperatures within the set of streams considered herein was more than sufficient to illustrate a number of specific limitations associated with statistical projections of stream temperature based on air temperature. Radar plots of Nash-Sutcliffe efficiency (NSE) values for

  3. Metastable Changes to the Temperature Coefficients of Thin-Film Photovoltaic Modules

    SciTech Connect

    Deceglie, M. G.; Silverman, T. J.; Marion, B.; Kurtz, S. R.

    2014-07-01

    Transient changes in the performance of thin-film modules with light exposure are a well-known and widely reported phenomenon. These changes are often the result of reversible metastabilities rather than irreversible changes. Here we consider how these metastable changes affect the temperature dependence of photovoltaic performance. We find that in CIGS modules exhibiting a metastable increase in performance with light exposure, the light exposure also induces an increase in the magnitude of the temperature coefficient. It is important to understand such changes when characterizing temperature coefficients and when analyzing the outdoor performance of newly installed modules.

  4. Forest fire danger rating in complex topography - results from a case study in the Bavarian Alps in autumn 2011

    NASA Astrophysics Data System (ADS)

    Schunk, C.; Wastl, C.; Leuchner, M.; Schuster, C.; Menzel, A.

    2013-09-01

    Forest fire danger rating based on sparse meteorological stations is known to be potentially misleading when assigned to larger areas of complex topography. This case study examines several fire danger indices based on data from two meteorological stations at different elevations during a major drought period. This drought was caused by a persistent high pressure system, inducing a pronounced temperature inversion and its associated thermal belt with much warmer, dryer conditions in intermediate elevations. Thus, a massive drying of fuels, leading to higher fire danger levels, and multiple fire occurrences at mid-slope positions were contrasted by moderate fire danger especially in the valleys. The ability of fire danger indices to resolve this situation was studied based on a comparison with the actual fire danger as determined from expert observations, fire occurrences and fuel moisture measurements. The results revealed that, during temperature inversion, differences in daily cycles of meteorological parameters influence fire danger and that these are not resolved by standard meteorological stations and fire danger indices (calculated on a once-a-day basis). Additional stations in higher locations or high-resolution meteorological models combined with fire danger indices accepting at least hourly input data may allow reasonable fire danger calculations under these circumstances.

  5. Forest fire danger rating in complex topography - results from a case study in the Bavarian Alps in autumn 2011

    NASA Astrophysics Data System (ADS)

    Schunk, C.; Wastl, C.; Leuchner, M.; Schuster, C.; Menzel, A.

    2013-04-01

    Forest fire danger rating based on sparse meteorological stations is known to be potentially misleading when assigned to larger areas with a complex topography. This case study examines outputs of several fire danger rating systems based on data from two meteorological stations in different elevations during a major drought period. This drought was caused by a persistent high pressure system, inducing a pronounced temperature inversion with cool, humid conditions in the lower and warmer, dryer conditions in the upper layer. Thus, a massive drying of fuels, leading to a high fire danger level and multiple fire occurrences at higher elevations were contrasted by moderate fire danger in the valleys. The relative accuracy of fire danger rating indices was studied based on a comparison with the actual fire danger as determined from expert observations, fire occurrences and fuel moisture measurements. The results revealed that, during temperature inversion, differences in daily cycles of meteorological parameters influence fire danger and that these are not resolved by standard meteorological stations and fire danger indices. Additional stations in higher locations or high-resolution meteorological models in combination with fire danger indices that accept hourly input data may allow reasonable fire danger calculations under these circumstances.

  6. Amplification and dampening of soil respiration by changes in temperature variability

    USGS Publications Warehouse

    Sierra, C.A.; Harmon, M.E.; Thomann, E.; Perakis, S.S.; Loescher, H.W.

    2011-01-01

    Accelerated release of carbon from soils is one of the most important feed backs related to anthropogenically induced climate change. Studies addressing the mechanisms for soil carbon release through organic matter decomposition have focused on the effect of changes in the average temperature, with little attention to changes in temperature vari-ability. Anthropogenic activities are likely to modify both the average state and the variability of the climatic system; therefore, the effects of future warming on decomposition should not only focus on trends in the average temperature, but also variability expressed as a change of the probability distribution of temperature.Using analytical and numerical analyses we tested common relationships between temperature and respiration and found that the variability of temperature plays an important role determining respiration rates of soil organic matter. Changes in temperature variability, without changes in the average temperature, can affect the amount of carbon released through respiration over the long term. Furthermore, simultaneous changes in the average and variance of temperature can either amplify or dampen there release of carbon through soil respiration as climate regimes change. The effects depend on the degree of convexity of the relationship between temperature and respiration and the magnitude of the change in temperature variance. A potential consequence of this effect of variability would be higher respiration in regions where both the mean and variance of temperature are expected to increase, such as in some low latitude regions; and lower amounts of respiration where the average temperature is expected to increase and the variance to decrease, such as in northern high latitudes.

  7. Optical glass: refractive index change with wavelength and temperature

    NASA Astrophysics Data System (ADS)

    Englert, Marion; Hartmann, Peter; Reichel, Steffen

    2014-05-01

    With the catalog of 1992 SCHOTT introduced two formulae each with six parameters for a better representation of the refractive index of optical glasses. The Sellmeier-equation improved the characterization of dispersion at room temperature and the Hoffmann equation that of its temperature dependence. Better representation had been expected because both formulae were derived from general dispersion theory. The original publication of Hoffmann et al. from 1992 contains first results on the accuracy of the fits. The extended use of the formulae has led to a collection of data allowing reviewing the adequacy of the Sellmeier-equation approach on a much broader basis. We compare fitted refractive index values with measured values for all wavelengths used at our precision refractive index goniometer. Data sets are available for specific melts of the four representative glass types N-BK7, N-FK5, LF5 and IRG2. For some materials, the optical glass N-LAF21, the IR glass IRG2 and the crystal CaF2, several sets of data for the temperature dependence of the refractive index are available thus giving evidence for the variation of these properties among melts of the same material.

  8. Telemetry pill versus rectal and esophageal temperature during extreme rates of exercise-induced core temperature change.

    PubMed

    Teunissen, L P J; de Haan, A; de Koning, J J; Daanen, H A M

    2012-06-01

    Core temperature measurement with an ingestible telemetry pill has been scarcely investigated during extreme rates of temperature change, induced by short high-intensity exercise in the heat. Therefore, nine participants performed a protocol of rest, (sub)maximal cycling and recovery at 30 °C. The pill temperature (T(pill)) was compared with the rectal temperature (T(re)) and esophageal temperature (T(es)). T(pill) corresponded well to T(re) during the entire trial, but deviated considerably from T(es) during the exercise and recovery periods. During maximal exercise, the average ΔT(pill)-T(re) and ΔT(pill)-T(es) were 0.13 ± 0.26 and -0.57 ± 0.53 °C, respectively. The response time from the start of exercise, the rate of change during exercise and the peak temperature were similar for T(pill) and T(re.) T(es) responded 5 min earlier, increased more than twice as fast and its peak value was 0.42 ± 0.46 °C higher than T(pill). In conclusion, also during considerable temperature changes at a very high rate, T(pill) is still a representative of T(re). The extent of the deviation in the pattern and peak values between T(pill) and T(es) (up to >1 °C) strengthens the assumption that T(pill) is unsuited to evaluate central blood temperature when body temperatures change rapidly. PMID:22551669

  9. Parameterization of temperature sensitivity of spring phenology and its application in explaining diverse phenological responses to temperature change.

    PubMed

    Wang, Huanjiong; Ge, Quansheng; Rutishauser, This; Dai, Yuxiao; Dai, Junhu

    2015-01-01

    Existing evidence of plant phenological change to temperature increase demonstrates that the phenological responsiveness is greater at warmer locations and in early-season plant species. Explanations of these findings are scarce and not settled. Some studies suggest considering phenology as one functional trait within a plant's life history strategy. In this study, we adapt an existing phenological model to derive a generalized sensitivity in space (SpaceSens) model for calculating temperature sensitivity of spring plant phenophases across species and locations. The SpaceSens model have three parameters, including the temperature at the onset date of phenophases (Tp), base temperature threshold (Tb) and the length of period (L) used to calculate the mean temperature when performing regression analysis between phenology and temperature. A case study on first leaf date of 20 plant species from eastern China shows that the change of Tp and Tb among different species accounts for interspecific difference in temperature sensitivity. Moreover, lower Tp at lower latitude is the main reason why spring phenological responsiveness is greater there. These results suggest that spring phenophases of more responsive, early-season plants (especially in low latitude) will probably continue to diverge from the other late-season plants with temperatures warming in the future. PMID:25743934

  10. Parameterization of temperature sensitivity of spring phenology and its application in explaining diverse phenological responses to temperature change

    PubMed Central

    Wang, Huanjiong; Ge, Quansheng; Rutishauser, This; Dai, Yuxiao; Dai, Junhu

    2015-01-01

    Existing evidence of plant phenological change to temperature increase demonstrates that the phenological responsiveness is greater at warmer locations and in early-season plant species. Explanations of these findings are scarce and not settled. Some studies suggest considering phenology as one functional trait within a plant's life history strategy. In this study, we adapt an existing phenological model to derive a generalized sensitivity in space (SpaceSens) model for calculating temperature sensitivity of spring plant phenophases across species and locations. The SpaceSens model have three parameters, including the temperature at the onset date of phenophases (Tp), base temperature threshold (Tb) and the length of period (L) used to calculate the mean temperature when performing regression analysis between phenology and temperature. A case study on first leaf date of 20 plant species from eastern China shows that the change of Tp and Tb among different species accounts for interspecific difference in temperature sensitivity. Moreover, lower Tp at lower latitude is the main reason why spring phenological responsiveness is greater there. These results suggest that spring phenophases of more responsive, early-season plants (especially in low latitude) will probably continue to diverge from the other late-season plants with temperatures warming in the future. PMID:25743934

  11. Intruder-induced change in condensation temperature of granular gases

    NASA Astrophysics Data System (ADS)

    Chen, Kuo-Ching; Hsieh, Wan-Lin; Lin, Chi-Hao

    2011-02-01

    The process from a gaseous state to a clustering state for a compartmentalized monodisperse granular gas is accompanied by a drop in the granular temperature to a condensation point. We show experimentally that adding an intruder generally results in a decrease in the condensation point, and a heavier intruder makes this decrease more pronounced. However, once the Brazil nut effect (the intruder on the top of clustering grains) occurs, the condensation point will rise. Through the balance of particle fluxes and the hydrodynamic balance of driving forces, we analytically calculated the condensation point for the monodisperse gases and the intruder-fluid mixtures. The analytical results match the experimental data.

  12. Substrate temperature changes during molecular beam epitaxy growth of GaMnAs

    SciTech Connect

    Novak, V.; Olejnik, K.; Cukr, M.; Smrcka, L.; Remes, Z.; Oswald, J.

    2007-10-15

    Our band gap spectroscopy measurements reveal a remarkably big increase of the substrate temperature during the low-temperature molecular beam epitaxy growth of GaMnAs layers. With the help of numerical simulations we explain the effect as a consequence of changing absorption/emission characteristics of the growing epilayer. We discuss possibilities for reducing the substrate temperature variations during the growth.

  13. Evidence for changes in the microwave brightness temperature and spectrum of Uranus

    NASA Technical Reports Server (NTRS)

    Batty, M. J.; Jauncey, D. L.; Rayner, P. T.; Gulkis, S.

    1981-01-01

    A new measurement of the microwave brightness temperature of Uranus at 13.1 cm wavelength yields an effective disk temperature of 255 + or - 18 K. Comparison with earlier measurements at nearby wavelengths reveals a doubling in brightness temperature in 14 yr. Observations at shorter wavelengths show significant changes in the shape of the microwave spectrum of the planet over the last decade.

  14. REVIEW OF TERMS FOR REGULATED VERSUS FORCED, NEUROCHEMICAL-INDUCED CHANGES IN BODY TEMPERATURE

    EPA Science Inventory

    Deviations of the body temperature of homeothermic animals may be regulated or forced. A regulated change in core temperature is caused by a natural or synthetic compound that displaces the set-point temperature. A forced shift occurs when an excessive environmental or endogenous...

  15. Estimation of surface temperature variations due to changes in sky and solar flux with elevation.

    USGS Publications Warehouse

    Hummer-Miller, S.

    1981-01-01

    Sky and solar radiance are of major importance in determining the ground temperature. Knowledge of their behavior is a fundamental part of surface temperature models. These 2 fluxes vary with elevation and this variation produces temperature changes. Therefore, when using thermal-property differences to discriminate geologic materials, these flux variations with elevation need to be considered. -from Author

  16. Climate change implications of soil temperature in the Mojave Desert, USA

    NASA Astrophysics Data System (ADS)

    Bai, Yanying; Scott, Thomas A.; Min, Qingwen

    2014-06-01

    Soil temperature plays an important role in physical, biological, and microbiological processes occurring in the soil, but it is rarely reported as an indicator of climate change. A long-term soil temperature database, collected in the Mojave Desert region from 1982-2000, was used to examine the relationship between regional climate change and soil temperature. During this 19-year study period, there was a warming trend in the Mojave Desert region. The soil temperature in this region, measured at 50-cm deep, increased at an average rate of 0.79°C per decade. The temporal changes of soil temperature and those of air temperature were highly correlated. Elevation was the dominating factor that affected the spatiotemporal variations of soil and air temperature.

  17. Simulation of regional temperature change effect of land cover change in agroforestry ecotone of Nenjiang River Basin in China

    NASA Astrophysics Data System (ADS)

    Liu, Tingxiang; Zhang, Shuwen; Yu, Lingxue; Bu, Kun; Yang, Jiuchun; Chang, Liping

    2016-02-01

    The Northeast China is one of typical regions experiencing intensive human activities within short time worldwide. Particularly, as the significant changes of agriculture land and forest, typical characteristics of pattern and process of agroforestry ecotone change formed in recent decades. The intensive land use change of agroforestry ecotone has made significant change for regional land cover, which had significant impact on the regional climate system elements and the interactions among them. This paper took agroforestry ecotone of Nenjiang River Basin in China as study region and simulated temperature change based on land cover change from 1950s to 1978 and from 1978 to 2010. The analysis of temperature difference sensitivity to land cover change based on Weather Research and Forecasting (WRF) model showed that the land cover change from 1950s to 1978 induced warming effect over all the study area, including the change of grassland to agriculture land, grassland to deciduous broad-leaved forest, and deciduous broad-leaved forest to shrub land. The land cover change from 1978 to 2010 induced cooling effect over all the study area, including the change of deciduous broad-leaved forest to agriculture land, grassland to agriculture land, shrub land to agriculture land, and deciduous broad-leaved forest to grassland. In addition, the warming and cooling effect of land cover change was more significant in the region scale than specific land cover change area.

  18. Validation of climate model-inferred regional temperature change for late-glacial Europe

    PubMed Central

    Heiri, Oliver; Brooks, Stephen J.; Renssen, Hans; Bedford, Alan; Hazekamp, Marjolein; Ilyashuk, Boris; Jeffers, Elizabeth S.; Lang, Barbara; Kirilova, Emiliya; Kuiper, Saskia; Millet, Laurent; Samartin, Stéphanie; Toth, Monika; Verbruggen, Frederike; Watson, Jenny E.; van Asch, Nelleke; Lammertsma, Emmy; Amon, Leeli; Birks, Hilary H.; Birks, H. John B.; Mortensen, Morten F.; Hoek, Wim Z.; Magyari, Enikö; Sobrino, Castor Muñoz; Seppä, Heikki; Tinner, Willy; Tonkov, Spassimir; Veski, Siim; Lotter, André F.

    2014-01-01

    Comparisons of climate model hindcasts with independent proxy data are essential for assessing model performance in non-analogue situations. However, standardized paleoclimate datasets for assessing the spatial pattern of past climatic change across continents are lacking for some of the most dynamic episodes of Earth's recent past. Here we present a new chironomid-based paleotemperature dataset designed to assess climate model hindcasts of regional summer temperature change in Europe during the late-glacial and early Holocene. Latitudinal and longitudinal patterns of inferred temperature change are in excellent agreement with simulations by the ECHAM-4 model, implying that atmospheric general circulation models like ECHAM-4 can successfully predict regionally diverging temperature trends in Europe, even when conditions differ significantly from present. However, ECHAM-4 infers larger amplitudes of change and higher temperatures during warm phases than our paleotemperature estimates, suggesting that this and similar models may overestimate past and potentially also future summer temperature changes in Europe. PMID:25208610

  19. Validation of climate model-inferred regional temperature change for late-glacial Europe.

    PubMed

    Heiri, Oliver; Brooks, Stephen J; Renssen, Hans; Bedford, Alan; Hazekamp, Marjolein; Ilyashuk, Boris; Jeffers, Elizabeth S; Lang, Barbara; Kirilova, Emiliya; Kuiper, Saskia; Millet, Laurent; Samartin, Stéphanie; Toth, Monika; Verbruggen, Frederike; Watson, Jenny E; van Asch, Nelleke; Lammertsma, Emmy; Amon, Leeli; Birks, Hilary H; Birks, H John B; Mortensen, Morten F; Hoek, Wim Z; Magyari, Enikö; Muñoz Sobrino, Castor; Seppä, Heikki; Tinner, Willy; Tonkov, Spassimir; Veski, Siim; Lotter, André F

    2014-01-01

    Comparisons of climate model hindcasts with independent proxy data are essential for assessing model performance in non-analogue situations. However, standardized palaeoclimate data sets for assessing the spatial pattern of past climatic change across continents are lacking for some of the most dynamic episodes of Earth's recent past. Here we present a new chironomid-based palaeotemperature dataset designed to assess climate model hindcasts of regional summer temperature change in Europe during the late-glacial and early Holocene. Latitudinal and longitudinal patterns of inferred temperature change are in excellent agreement with simulations by the ECHAM-4 model, implying that atmospheric general circulation models like ECHAM-4 can successfully predict regionally diverging temperature trends in Europe, even when conditions differ significantly from present. However, ECHAM-4 infers larger amplitudes of change and higher temperatures during warm phases than our palaeotemperature estimates, suggesting that this and similar models may overestimate past and potentially also future summer temperature changes in Europe. PMID:25208610

  20. Is there really an upper limit to river water temperatures in a changing climate?

    NASA Astrophysics Data System (ADS)

    Shaw, S. B.

    2011-12-01

    In recent efforts to model river temperatures in a changing climate, investigators have frequently applied an s-shaped logistic equation to relate water temperatures to air temperatures. This s-shaped model has been justified by the presence of the freezing point at low temperatures and supposed enhanced evapotranspiration (ET) at high temperatures. Looking at large river systems (> 5000 km2) where mean air and water temperatures are in relative equilibrium, we analyze the 5-day mean air/water temperature relationship of 12 river systems located in different climatological regions of the US to reassess whether there is actually an upper limit to maximum river temperatures. For all 12 systems, a logistic regression model performs better than a linear regression model in relating river water temperatures to air temperature. However, direct examination of the air/water relationship indicates that the improvement in fit often originates only at low temperatures. Of the five systems where an improvement occurs at high temperatures, they are either located in arid regions, have mountain snowmelt extending into the early summer, or exhibit strong hysteresis. An assessment of hourly energy balance data for varying geographic regions suggests that arid regions are the only locales where energy losses at high temperatures due to ET may exceed energy inputs, thus leading to a plateau in water temperatures. This research suggests that logistic regression equations should be applied only after carefully considering the processes that may control temperature in a changing climate on the river of interest.

  1. The Temperature Changes of Refractive Indices and Thickness of Doped Triglycine Sulfate Crystals

    NASA Astrophysics Data System (ADS)

    Kurlyak, V. Yu.; Stadnyk, V. Y.; Gaba, V. M.; Kohut, Z. O.; Matviishyn, I. M.

    2016-07-01

    The temperature dependences of the optical path difference δΔi and the relative changes in the thickness δli/l of TGS crystals doped with L-threonine are studied. The temperature dependences of the relative changes in the refractive indices δni/(n - 1), coefficients of anisotropy for refractive indices, and linear expansion have been calculated. Characteristic minimum has been detected on these curves near the phase transition temperature.

  2. AO/NAO response to climate change: 2. Relative importance of low- and high-latitude temperature changes

    NASA Astrophysics Data System (ADS)

    Rind, D.; Perlwitz, J.; Lonergan, P.; Lerner, J.

    2005-06-01

    We address the issue of why different models may be getting different responses of the AO/NAO in climate change experiments. The results from part 1 (Rind et al., 2005) suggest that for substantive climate changes, the differences are likely to be found in the patterns of tropospheric climate change, rather than from the stratosphere. We assess the various tropospheric forcings through a variety of experiments. We first use extreme paleoclimate experiments (Ice Age, Paleocene) which feature large variations in the low level latitudinal temperature gradient; the results show that under these circumstances, changes in the eddy transport of sensible heat, and in situ high latitude forcing, dominate the AO response. We next test the effect of more modest SST temperature gradient changes in the current climate, and find a similar result with a model configuration that does not easily transport the low level temperature changes into the upper troposphere. We then reanalyze the results from different 2 × CO2 experiments with the GISS model and find that they can be understood by assessing: (1) the magnitude of tropical SST warming; (2) the translations of that warming into the upper troposphere; (3) the change in the extratropical low altitude temperature gradient; and (4) the change in the high latitude SST/sea ice response. We suggest that these features might explain the varying results among modeling groups, and that forecasts will not converge until these features do.

  3. Investigation of medium and high temperature phase change materials

    NASA Technical Reports Server (NTRS)

    Heine, D.; Kraehling, H.

    1979-01-01

    A detailed description of the programs for acquisition and analysis of the test results is given. Basically it concerns three programs. The TEST program controls the recording of the test data. With the THELLI program it is possible to follow the temperature curve recorded for each individual thermoelement during the test. With the AUSW program the test data can be analyzed, to determine, for example, the melting point and the start of melting. The first results of the service life tests are discussed. From these it is attempted to draw inferences for the subsequent tests. An attempt is made to focus on the determination of the area-related mass loss, the reduction in thickness and the corrosion rate as well as optical and scanning electron microscope evaluation.

  4. Impacts of Low-Flow and Stream-Temperature Changes on Endangered Atlantic Salmon - Current Research

    USGS Publications Warehouse

    Dudley, Robert W.; Hodgkins, Glenn A.; Letcher, Benjamin H.

    2008-01-01

    Recent climate studies in New England and the northeastern United States have shown evidence of physical changes over time, including trends toward earlier snowmelt runoff, decreasing river ice, and increasing spring water temperatures. A U.S. Geological Survey (USGS) study funded by the National Global Warming and Wildlife Science Center will be investigating changes in summer low streamflows and stream temperatures and the potential effects of those changes on endangered Atlantic salmon populations. The study also will evaluate management options that would be most likely to mitigate the effects of any changes in streamflow and temperature.

  5. While Travelers Sleep, Brain Patrols for Danger

    MedlinePlus

    ... medlineplus.gov/news/fullstory_158440.html While Travelers Sleep, Brain Patrols for Danger Study findings may explain ... THURSDAY, April 21, 2016 (HealthDay News) -- When you sleep in a new place, a part of your ...

  6. While Travelers Sleep, Brain Patrols for Danger

    MedlinePlus

    ... gov/medlineplus/news/fullstory_158440.html While Travelers Sleep, Brain Patrols for Danger Study findings may explain ... THURSDAY, April 21, 2016 (HealthDay News) -- When you sleep in a new place, a part of your ...

  7. Booze, High Blood Pressure a Dangerous Mix

    MedlinePlus

    ... nih.gov/medlineplus/news/fullstory_158828.html Booze, High Blood Pressure a Dangerous Mix Study links moderate drinking to heart damage in people with hypertension To use the sharing features on this page, ...

  8. Contrasting effects of temperature and precipitation change on amphibian phenology, abundance and performance.

    PubMed

    Ficetola, Gentile Francesco; Maiorano, Luigi

    2016-07-01

    Climate change is determining a generalized phenological advancement, and amphibians are among the taxa showing the strongest phenological responsiveness to warming temperatures. Amphibians are strongly influenced by climate change, but we do not have a clear picture of how climate influences important parameters of amphibian populations, such as abundance, survival, breeding success and morphology. Furthermore, the relative impact of temperature and precipitation change remains underappreciated. We used Bayesian meta-analysis and meta-regression to quantify the impact of temperature and precipitation change on amphibian phenology, abundance, individual features and performance. We obtained effect sizes from studies performed in five continents. Temperature increase was the major driver of phenological advancement, while the impact of precipitation on phenology was weak. Conversely, population dynamics was mostly determined by precipitation: negative trends were associated with drying regimes. The impact of precipitation on abundance was particularly strong in tropical areas, while the importance of temperature was feeble. Both temperature and precipitation influenced parameters representing breeding performance, morphology, developmental rate and survival, but the response was highly heterogeneous among species. For instance, warming temperature increased body size in some species, and decreased size in others. Similarly, rainy periods increased survival of some species and reduced the survival of others. Our study showed contrasting impacts of temperature and precipitation changes on amphibian populations. Both climatic parameters strongly influenced amphibian performance, but temperature was the major determinant of the phenological changes, while precipitation had the major role on population dynamics, with alarming declines associated with drying trends. PMID:27008454

  9. Effect of Climate Change on Soil Temperature in Swedish Boreal Forests

    PubMed Central

    Jungqvist, Gunnar; Oni, Stephen K.; Teutschbein, Claudia; Futter, Martyn N.

    2014-01-01

    Complex non-linear relationships exist between air and soil temperature responses to climate change. Despite its influence on hydrological and biogeochemical processes, soil temperature has received less attention in climate impact studies. Here we present and apply an empirical soil temperature model to four forest sites along a climatic gradient of Sweden. Future air and soil temperature were projected using an ensemble of regional climate models. Annual average air and soil temperatures were projected to increase, but complex dynamics were projected on a seasonal scale. Future changes in winter soil temperature were strongly dependent on projected snow cover. At the northernmost site, winter soil temperatures changed very little due to insulating effects of snow cover but southern sites with little or no snow cover showed the largest projected winter soil warming. Projected soil warming was greatest in the spring (up to 4°C) in the north, suggesting earlier snowmelt, extension of growing season length and possible northward shifts in the boreal biome. This showed that the projected effects of climate change on soil temperature in snow dominated regions are complex and general assumptions of future soil temperature responses to climate change based on air temperature alone are inadequate and should be avoided in boreal regions. PMID:24747938

  10. Temperature regulation and metabolism in rats exposed perinatally to dioxin: permanent change in regulated body temperature?

    PubMed

    Gordon, C J; Gray, L E; Monteiro-Riviere, N A; Miller, D B

    1995-07-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has been shown to lower thyroxine levels and cause hypothermia in the adult rat; however, there is little known regarding the perinatal effects of TCDD on metabolism and temperature regulation of the offspring. To address this issue, thermoregulatory responses were assessed in adult male rat offspring exposed perinatally to 1.0 micrograms TCDD/kg body wt by gavage on Gestational Day 15. Individual castrated offspring were placed in a gradient-layer calorimeter for 5 hr during their nocturnal period while ambient temperature (Ta) was maintained at 10, 16, 24, or 28 degrees C. Metabolic rate (M), as measured from the total heat loss in the calorimeter, was determined along with evaporative heat loss (EHL), dry thermal conductance, and body core temperature (Tc). Animals exposed to TCDD had a significantly lower body temperature at TaS of 10, 16, and 24 degrees C and a higher thermal conductance. M was unaffected by TCDD, indicating that TCDD did not impair the effector to regulate Tc during cold exposure. EHL was also unaffected by TCDD. Skin blood flow of the interscapular area was measured in anesthetized rats with laser Doppler velocimetry and found to be the same in control and TCDD groups. The reduction in body temperature over a wide range of TaS concomitant with normal thermoregulatory effector function suggests that perinatal exposure to TCDD results in a reduction in the regulated body temperature (i.e., decrease in set-point). PMID:7597705