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Sample records for erisma uncinatum warm

  1. Enhanced resistance to four species of Clypeorrhynchan pests in Neotyphodium uncinatum infected Italian ryegrass.

    PubMed

    Matsukura, Keiichiro; Shiba, Takuya; Sasaki, Tohru; Matsumura, Masaya

    2012-02-01

    Particular alkaloids produced by Neotyphodium endophytes show toxicity to invertebrates. Italian ryegrass (Lolium multiflorum Lamarck) cultivars and strains that are symbiotic with Neotyphodium endophytes have been recently established in Japan. N. uncinatum-infected Italian ryegrass lines accumulate N-formylloline, a type of loline alkaloid (1-aminopyrrolizidine) showing neurotoxicity to herbivorous insects. This study investigated the toxicity of N-formylloline and resistance of N. uncinatum-infected Italian ryegrass to vascular-sap feeding Clypeorrhynchan pests. When four vascular-sap feeding insects: Laodelphax striatellus (Fallén) (Homoptera: Delphacidae), Sogatella furcifera (Horváth) (Homoptera: Delphacidae), Cicadulina bipunctata (Melichar) (Homoptera: Cicadellidae), and Nephotettix cincticeps (Uhler) (Homoptera: Cicadellidae) fed on N. uncinatum-infected Italian ryegrass, significant decreases in survival rate were observed for three phloem-sap feeders but not for a xylem-sap feeder, N. cincticeps. This result suggests an uneven distribution of N-formylloline among plant tissues. A potency assay for N-formylloline using a Parafilm feeding sachet and a quantitative analysis of N-formylloline in plant showed a concentration-dependent lethal effect of N-formylloline on all four tested vascular-sap feeders. Our results strongly suggest that N. uncinatum-infected plants can control some Clypeorrhynchan pests in crop fields.

  2. Gene clusters for insecticidal loline alkaloids in the grass-endophytic fungus Neotyphodium uncinatum.

    PubMed

    Spiering, Martin J; Moon, Christina D; Wilkinson, Heather H; Schardl, Christopher L

    2005-03-01

    Loline alkaloids are produced by mutualistic fungi symbiotic with grasses, and they protect the host plants from insects. Here we identify in the fungal symbiont, Neotyphodium uncinatum, two homologous gene clusters (LOL-1 and LOL-2) associated with loline-alkaloid production. Nine genes were identified in a 25-kb region of LOL-1 and designated (in order) lolF-1, lolC-1, lolD-1, lolO-1, lolA-1, lolU-1, lolP-1, lolT-1, and lolE-1. LOL-2 contained the homologs lolC-2 through lolE-2 in the same order and orientation. Also identified was lolF-2, but its possible linkage with either cluster was undetermined. Most lol genes were regulated in N. uncinatum and N. coenophialum, and all were expressed concomitantly with loline-alkaloid biosynthesis. A lolC-2 RNA-interference (RNAi) construct was introduced into N. uncinatum, and in two independent transformants, RNAi significantly decreased lolC expression (P < 0.01) and loline-alkaloid accumulation in culture (P < 0.001) compared to vector-only controls, indicating involvement of lolC in biosynthesis of lolines. The predicted LolU protein has a DNA-binding site signature, and the relationships of other lol-gene products indicate that the pathway has evolved from various different primary and secondary biosynthesis pathways.

  3. Gene Clusters for Insecticidal Loline Alkaloids in the Grass-Endophytic Fungus Neotyphodium uncinatum

    PubMed Central

    Spiering, Martin J.; Moon, Christina D.; Wilkinson, Heather H.; Schardl, Christopher L.

    2005-01-01

    Loline alkaloids are produced by mutualistic fungi symbiotic with grasses, and they protect the host plants from insects. Here we identify in the fungal symbiont, Neotyphodium uncinatum, two homologous gene clusters (LOL-1 and LOL-2) associated with loline-alkaloid production. Nine genes were identified in a 25-kb region of LOL-1 and designated (in order) lolF-1, lolC-1, lolD-1, lolO-1, lolA-1, lolU-1, lolP-1, lolT-1, and lolE-1. LOL-2 contained the homologs lolC-2 through lolE-2 in the same order and orientation. Also identified was lolF-2, but its possible linkage with either cluster was undetermined. Most lol genes were regulated in N. uncinatum and N. coenophialum, and all were expressed concomitantly with loline-alkaloid biosynthesis. A lolC-2 RNA-interference (RNAi) construct was introduced into N. uncinatum, and in two independent transformants, RNAi significantly decreased lolC expression (P < 0.01) and loline-alkaloid accumulation in culture (P < 0.001) compared to vector-only controls, indicating involvement of lolC in biosynthesis of lolines. The predicted LolU protein has a DNA-binding site signature, and the relationships of other lol-gene products indicate that the pathway has evolved from various different primary and secondary biosynthesis pathways. PMID:15654104

  4. Coregulated expression of loline alkaloid-biosynthesis genes in Neotyphodium uncinatum cultures.

    PubMed

    Zhang, Dong-Xiu; Stromberg, Arnold J; Spiering, Martin J; Schardl, Christopher L

    2009-08-01

    Epichloë endophytes (holomorphic Epichloë spp. and anamorphic Neotyphodium spp.) are systemic, often heritable symbionts of cool-season grasses (subfamily Pooideae). Many epichloae provide protection to their hosts by producing anti-insect compounds. Among these are the loline alkaloids (LA), which are toxic and deterrent to a broad range of herbivorous insects but not to mammalian herbivores. LOL, a gene cluster containing nine genes, is associated with LA biosynthesis. We investigated coordinate regulation between LOL-gene expression and LA production in minimal medium (MM) cultures of Neotyphodium uncinatum. Expression of all LOL genes significantly fit temporal quadratic patterns during LA production. LOL-gene expression started before LA were detectable, and increased while LA accumulated. The highest gene expression level was reached at close to the time of most rapid LA accumulation, and gene expression declined to a very low level as amounts of LA plateaued. Temporal expression profiles of the nine LOL genes were tightly correlated with each other, but not as tightly correlated with proC and metE (genes for biosynthesis of precursor amino acids). Furthermore, the start days and peak days of expression significantly correlated with the order of the LOL-cluster genes in the genome. Hierarchical cluster analysis indicated three pairs of genes-lolA and lolC, lolO and lolD, and lolT and lolE-expression of which was especially tightly correlated. Of these, lolA and lolC tended to be expressed early, and lolT and lolE tended to be expressed late, in keeping with the putative roles of the respective gene products in the LA-biosynthesis pathway. Several common transcriptional binding sites were discovered in the LOL upstream regions. However, low expression of P(lolC2)uidA and P(lolA2)uidA in N. uncinatum transformants suggested induced expression of LOL genes might be subject to position effect at the LOL locus.

  5. Condensed tannin and saponin content of Vigna unguiculata (L.) Walp, Desmodium uncinatum, Stylosanthes guianensis and Stylosanthes scabra grown in Zimbabwe.

    PubMed

    Baloyi, J J; Ngongoni, N T; Topps, J H; Acamovic, T; Hamudikuwanda, H

    2001-02-01

    Samples of the tropical forage legumes Vigna unguiculata (L.) Walp (cowpea), Desmodium uncinatum (silverleaf desmodium), Stylosanthes guianensis (oxley fine stem stylo) and Stylosanthes scabra (fitzroy) and of natural pasture (veld) hay were analysed and ranked according to their proanthocyanidin (PA) and saponin content. Silverleaf desmodium and fitzroy leaf and stem samples of different ages were also separately analysed for the PA contents. All the samples analysed contained some PA but no saponins. High levels of PA were detected in silverleaf desmodium and very low levels in veld hay and cowpea. In all samples, more of the tannins were bound to protein or neutral detergent fibre (NDF) than were extractable, most being bound to proteins. The proportion of the unextractable PA was greater in younger than in mature materials.

  6. Characterization of the Key Aroma Compounds in White Alba Truffle (Tuber magnatum pico) and Burgundy Truffle (Tuber uncinatum) by Means of the Sensomics Approach.

    PubMed

    Schmidberger, Philipp C; Schieberle, Peter

    2017-10-11

    Aroma extract dilution analysis of distillates prepared by solvent extraction and solvent-assisted flavor evaporation distillation from white Alba truffle (WAT; Tuber magnatum pico) and Burgundy truffle (BT; Tuber uncinatum) revealed 20 odor-active regions in the flavor dilution (FD) factor range of 16-4096 in WAT and 25 in BT. The identification experiments in combination with the FD factors showed clear differences in the overall set of key odorants of both fungi. While 3-(methylthio)propanal (potato-like) followed by 2- and 3-methylbutanal (malty), 2,3-butanedione (buttery), and bis(methylthio)methane (garlic-like) showed the highest FD factors in WAT, 2,3-butanedione, phenylacetic acid (honey-like), and vanillin (vanilla-like) had the highest FD factors in BT. Odor activity values (OAVs, ratio of concentration to odor thresholds), which were calculated on the basis of quantitative data obtained by stable isotope dilution assays, of >1000 for bis(methylthio)methane, 3-methylbutanal, and 3,4-dihydro-2-(H)pyrrol (1-pyrroline) revealed they are key contributors to the aroma of WAT. In BT, 1-pyrroline and 2,3-butanedione showed the highest OAVs of 1530 and 1130, respectively. Aroma recombination experiments successfully mimicked the overall aroma profiles of both fungi when all odorants showing OAVs of >1 were combined. Omission experiments confirmed the amine-like and sperm-like smell of 1-pyrroline, identified for the first time as a key odorant in both truffle species.

  7. [Electron microscope study of spermatogenesis in two cestodes acanthobothrium filicolle benedenii Loennberg, 1889 and Onchobothrium uncinatum (Rud., 1819) (Tetraphyllidea, Onchobothriidae) (author's transl)].

    PubMed

    Maamouri, F M; Swiderski, Z

    1975-10-31

    The spermatogenesis, spermatozoon differentiation and fine structure of Acanthobothrium filicolle benedenii Loennberg, 1889 and Onchobothrium uncinatum (Rud., 1819) were studied by means of light and electron microscopy. Spermatogenesis in both species is of the rosette type. During sperm differentiation, the five following stages have been distinguished: (1) formation of arching membranes and differentiation zone; (2) nuclear elongation; (3) formation of two flagella with a median cytoplasmic process; (4) flagellar rotation; (5) fusion of two flagella with the median cytoplasmic process induced by the migration of nucleus into the latter. The mature spermatozoa of both species are threadlike structures about 250 mum long. They consist of two axonemes of the platyhelminth type (9+1 pattern), elongated nucleus and cortical microtubules embedded in a cytoplasmic matrix containing numerus beta-glycogen particles. The body which appears on cross-sections as crest, lateral with respect to the axoneme, is present in both species. Such a body is reported for the first time in Cestode spermatozoa. There is no mitochondrion in the two Onchobothriidae sperms studied.

  8. Global Warming.

    ERIC Educational Resources Information Center

    Hileman, Bette

    1989-01-01

    States the foundations of the theory of global warming. Describes methodologies used to measure the changes in the atmosphere. Discusses steps currently being taken in the United States and the world to slow the warming trend. Recognizes many sources for the warming and the possible effects on the earth. (MVL)

  9. Global Warming.

    ERIC Educational Resources Information Center

    Hileman, Bette

    1989-01-01

    States the foundations of the theory of global warming. Describes methodologies used to measure the changes in the atmosphere. Discusses steps currently being taken in the United States and the world to slow the warming trend. Recognizes many sources for the warming and the possible effects on the earth. (MVL)

  10. Global Warming?

    ERIC Educational Resources Information Center

    Eichman, Julia Christensen; Brown, Jeff A.

    1994-01-01

    Presents information and data on an experiment designed to test whether different atmosphere compositions are affected by light and temperature during both cooling and heating. Although flawed, the experiment should help students appreciate the difficulties that researchers face when trying to find evidence of global warming. (PR)

  11. Global Warming?

    ERIC Educational Resources Information Center

    Eichman, Julia Christensen; Brown, Jeff A.

    1994-01-01

    Presents information and data on an experiment designed to test whether different atmosphere compositions are affected by light and temperature during both cooling and heating. Although flawed, the experiment should help students appreciate the difficulties that researchers face when trying to find evidence of global warming. (PR)

  12. Global warming

    NASA Astrophysics Data System (ADS)

    Houghton, John

    2005-06-01

    'Global warming' is a phrase that refers to the effect on the climate of human activities, in particular the burning of fossil fuels (coal, oil and gas) and large-scale deforestation, which cause emissions to the atmosphere of large amounts of 'greenhouse gases', of which the most important is carbon dioxide. Such gases absorb infrared radiation emitted by the Earth's surface and act as blankets over the surface keeping it warmer than it would otherwise be. Associated with this warming are changes of climate. The basic science of the 'greenhouse effect' that leads to the warming is well understood. More detailed understanding relies on numerical models of the climate that integrate the basic dynamical and physical equations describing the complete climate system. Many of the likely characteristics of the resulting changes in climate (such as more frequent heat waves, increases in rainfall, increase in frequency and intensity of many extreme climate events) can be identified. Substantial uncertainties remain in knowledge of some of the feedbacks within the climate system (that affect the overall magnitude of change) and in much of the detail of likely regional change. Because of its negative impacts on human communities (including for instance substantial sea-level rise) and on ecosystems, global warming is the most important environmental problem the world faces. Adaptation to the inevitable impacts and mitigation to reduce their magnitude are both necessary. International action is being taken by the world's scientific and political communities. Because of the need for urgent action, the greatest challenge is to move rapidly to much increased energy efficiency and to non-fossil-fuel energy sources.

  13. Warm Up with Skill.

    ERIC Educational Resources Information Center

    Hoyle, R. J.; Smith, Robert F.

    1989-01-01

    Too little time is often spent on warm-up activities in the school or recreation class. Warm-ups are often perfunctory and unimaginative. Several suggestions are made for warm-up activities that incorporate both previously learned and new skills, while preparing the body for more vigorous activity. (IAH)

  14. Global Warming Trends.

    ERIC Educational Resources Information Center

    Jones, Philip D.; Wigley, Tom M. L.

    1990-01-01

    Results from the analysis of land and marine records from the past century are presented. It is indicated that the planet earth has warmed about one-half of a degree celsius. The uncertainty of these measurements and future warming trends are discussed. (CW)

  15. Warm-Up Activities.

    ERIC Educational Resources Information Center

    Mingguang, Yang

    1999-01-01

    Discusses how warm-up activities can help to make the English-as-a-foreign-language classroom a lively and interesting place. Warm-up activities are games carried out at the beginning of each class to motivate students to make good use of class time. (Author/VWL)

  16. Global Warming Trends.

    ERIC Educational Resources Information Center

    Jones, Philip D.; Wigley, Tom M. L.

    1990-01-01

    Results from the analysis of land and marine records from the past century are presented. It is indicated that the planet earth has warmed about one-half of a degree celsius. The uncertainty of these measurements and future warming trends are discussed. (CW)

  17. Warm autoimmune hemolytic anemia.

    PubMed

    Naik, Rakhi

    2015-06-01

    Warm autoimmune hemolytic anemia (AIHA) is defined as the destruction of circulating red blood cells (RBCs) in the setting of anti-RBC autoantibodies that optimally react at 37°C. The pathophysiology of disease involves phagocytosis of autoantibody-coated RBCs in the spleen and complement-mediated hemolysis. Thus far, treatment is aimed at decreasing autoantibody production with immunosuppression or reducing phagocytosis of affected cells in the spleen. The role of complement inhibitors in warm AIHA has not been explored. This article addresses the diagnosis, etiology, and treatment of warm AIHA and highlights the role of complement in disease pathology.

  18. Reconciling Warming Trends

    NASA Technical Reports Server (NTRS)

    Schmidt, Gavin A.; Shindell, Drew T.; Tsigaridis, Konstantinos

    2014-01-01

    Climate models projected stronger warming over the past 15 years than has been seen in observations. Conspiring factors of errors in volcanic and solar inputs, representations of aerosols, and El NiNo evolution, may explain most of the discrepancy.

  19. Warm and Cool Dinosaurs.

    ERIC Educational Resources Information Center

    Mannlein, Sally

    2001-01-01

    Presents an art activity in which first grade students draw dinosaurs in order to learn about the concept of warm and cool colors. Explains how the activity also helped the students learn about the concept of distance when drawing. (CMK)

  20. Global warming elucidated

    SciTech Connect

    Shen, S.

    1995-03-01

    The meaning of global warming and its relevance to everyday life is explained. Simple thermodynamics is used to predict an oscillatory nature of the change in climate due to global warming. Global warming causes extreme events and bad weather in the near term. In the long term it may cause the earth to transition to another equilibrium state through many oscillation in climatic patterns. The magnitudes of these oscillations could easily exceed the difference between the end points. The author further explains why many no longer fully understands the nature and magnitudes of common phenomena such as storms and wind speeds because of these oscillations, and the absorptive properties of clouds. The author links the increase in duration of the El Nino to global warming, and further predicts public health risks as the earth transitions to another equilibrium state in its young history.

  1. Warm and Cool Dinosaurs.

    ERIC Educational Resources Information Center

    Mannlein, Sally

    2001-01-01

    Presents an art activity in which first grade students draw dinosaurs in order to learn about the concept of warm and cool colors. Explains how the activity also helped the students learn about the concept of distance when drawing. (CMK)

  2. Warm core rings

    NASA Astrophysics Data System (ADS)

    Bell, Peter M.

    Gulf stream phenomena have been the focus of numerous studies by U.S. and Canadian oceanographic laboratories. Two years ago, observations of warm core rings associated with the Gulf Stream were reported in The Oceanography Report, (November 2, 1982, p. 834). It was noted then that the structure of warm core rings can undergo rapid transformation. Recently, a multidisciplinary group of physical and biological oceanographic institutions has examined the evolution of warm core rings in detail [Nature, 308, pp. 837-840, 1984]. The study has involved research vessels Endeavor, Atlantis II, and Albatross IV for surface measurements of temperature, salinity, and for measurement surface pigments to assess the concentration of marine plants. The results are that even though warm core rings are often very stable, undergoing only slow changes, it turns out that major alterations in structure can and do occur in short periods of 2-5 days.

  3. Polar Warming Drivers

    NASA Astrophysics Data System (ADS)

    McDunn, T. L.; Bougher, S. W.; Mischna, M. A.; Murphy, J. R.

    2012-12-01

    Polar warming is a dynamically induced temperature enhancement over mid-to-high latitudes that results in a reversed (poleward) meridional temperature gradient. This phenomenon was recently characterized over the 40-90 km altitude region [1] based on nearly three martian years of Mars Climate Sounder observations [2, 3]. Here we investigate which forcing mechanisms affect the magnitude and distribution of the observed polar warming by conducting simulations with the Mars Weather Research and Forecasting General Circulation Model [4, 5]. We present simulations confirming the influence topography [6] and dust loading [e.g., 7] have upon polar warming. We then present simulations illustrating the modulating influence gravity wave momentum deposition exerts upon polar warming, consistent with previous modeling studies [e.g., 8]. The results of this investigation suggest the magnitude and distribution of polar warming in the martian middle atmosphere is modified by gravity wave activity and that the characteristics of the gravity waves that most significantly affect polar warming vary with season. References: [1] McDunn, et al., 2012 (JGR), [2]Kleinböhl, et al., 2009 (JGR), [3] Kleinböhl, et al., 2011 (JQSRT), [4] Richardson, et al., 2007 (JGR), [5] Mischna, et al., 2011 (Planet. Space Sci.), [6] Richardson and Wilson, 2002 (Nature), [7] Haberle, et al., 1982 (Icarus), [8] Barnes, 1990 (JGR).

  4. Warm up to the idea: Global warming is here

    SciTech Connect

    Lynch, C.F.

    1996-07-01

    This article summarizes recent information about global warming as well as the history of greenhouse gas emissions which have lead to more and more evidence of global warming. The primary source detailed is the second major study report on global warming by the Intergovernmental Panel on climate change. Along with comments about the environmental effects of global warming such as coastline submersion, the economic, social and political aspects of alleviating greenhouse emissions and the threat of global warming are discussed.

  5. Global warming on trial

    SciTech Connect

    Broeker, W.S.

    1992-04-01

    Jim Hansen, a climatologist at NASA's Goddard Space Institute, is convinced that the earth's temperature is rising and places the blame on the buildup of greenhouse gases in the atmosphere. Unconvinced, John Sununu, former White House chief of staff, doubts that the warming will be great enough to produce serious threat and fears that measures to reduce the emissions would throw a wrench into the gears that drive the Unites States' troubled economy. During his three years at the White House, Sununu's view prevailed, and although his role in the debate has diminished, others continue to cast doubt on the reality of global warming. A new lobbying group called the Climate Council has been created to do just this. Burning fossil fuels is not the only problem; a fifth of emissions of carbon dioxide now come from clearing and burning forests. Scientists are also tracking a host of other greenhouse gases that emanate from a variety of human activities; the warming effect of methane, chlorofluorocarbons and nitrous oxide combined equals that of carbon dioxide. Although the current warming from these gases may be difficult to detect against the background noise of natural climate variation, most climatologists are certain that as the gases continue to accumulate, increases in the earth's temperature will become evident even to skeptics. If the reality of global warming were put on trial, each side would have trouble making its case. Jim Hansen's side could not prove beyond a reasonable doubt that carbon dioxide and other greenhouse gases have warmed the planet. But neither could John Sununu's side prove beyond a reasonable doubt that the warming expected from greenhouse gases has not occurred. To see why each side would have difficulty proving its case, this article reviews the arguments that might be presented in such a hearing.

  6. G-warm inflation

    NASA Astrophysics Data System (ADS)

    Herrera, Ramón

    2017-05-01

    A warm inflationary universe in the context of Galileon model or G-model is studied. Under a general formalism we study the inflationary dynamics and the cosmological perturbations considering a coupling of the form G(phi,X)=g(phi) X. As a concrete example, we consider an exponential potential together with the cases in which the dissipation and Galilean coefficients are constants. Also, we study the weak regime given by the condition R<1+3gHdot phi, and the strong regime in which 1warm inflation, assuming the condition for warm inflation in which the temperature T>H, the conditions or the weak and strong regimes, together with the consistency relation r=r(ns) from Planck data.

  7. Warm and Cool Cityscapes

    ERIC Educational Resources Information Center

    Jubelirer, Shelly

    2012-01-01

    Painting cityscapes is a great way to teach first-grade students about warm and cool colors. Before the painting begins, the author and her class have an in-depth discussion about big cities and what types of buildings or structures that might be seen in them. They talk about large apartment and condo buildings, skyscrapers, art museums,…

  8. Warm and Cool Cityscapes

    ERIC Educational Resources Information Center

    Jubelirer, Shelly

    2012-01-01

    Painting cityscapes is a great way to teach first-grade students about warm and cool colors. Before the painting begins, the author and her class have an in-depth discussion about big cities and what types of buildings or structures that might be seen in them. They talk about large apartment and condo buildings, skyscrapers, art museums,…

  9. Warming Up to Communication.

    ERIC Educational Resources Information Center

    Garner, Lucia Caycedo; Rusch, Debbie

    Daily warm-up exercises are advocated as a means of bridging the gap between previously unrelated activities outside the classroom and immersion into the second language, relaxing the class, and establishing a mood for communication. Variety, careful preparation, assuring that the students understand the activity, feeling free to discontinue an…

  10. Global warming 'confirmed'

    NASA Astrophysics Data System (ADS)

    2011-12-01

    In October, the Berkeley Earth Surface Temperature project, funded in part by climate sceptics, concluded that the Earth is warming based on the most comprehensive review of the data yet. Nature Climate Change talks to the project's director, physicist Richard Muller.

  11. -induced continental warming

    NASA Astrophysics Data System (ADS)

    Kamae, Youichi; Watanabe, Masahiro; Kimoto, Masahide; Shiogama, Hideo

    2014-11-01

    In this the second of a two-part study, we examine the physical mechanisms responsible for the increasing contrast of the land-sea surface air temperature (SAT) in summertime over the Far East, as observed in recent decades and revealed in future climate projections obtained from a series of transient warming and sensitivity experiments conducted under the umbrella of the Coupled Model Intercomparison Project phase 5. On a global perspective, a strengthening of land-sea SAT contrast in the transient warming simulations of coupled atmosphere-ocean general circulation models is attributed to an increase in sea surface temperature (SST). However, in boreal summer, the strengthened contrast over the Far East is reproduced only by increasing atmospheric CO2 concentration. In response to SST increase alone, the tropospheric warming over the interior of the mid- to high-latitude continents including Eurasia are weaker than those over the surrounding oceans, leading to a weakening of the land-sea SAT contrast over the Far East. Thus, the increasing contrast and associated change in atmospheric circulation over East Asia is explained by CO2-induced continental warming. The degree of strengthening of the land-sea SAT contrast varies in different transient warming scenarios, but is reproduced through a combination of the CO2-induced positive and SST-induced negative contributions to the land-sea contrast. These results imply that changes of climate patterns over the land-ocean boundary regions are sensitive to future scenarios of CO2 concentration pathways including extreme cases.

  12. Warm Little Inflaton.

    PubMed

    Bastero-Gil, Mar; Berera, Arjun; Ramos, Rudnei O; Rosa, João G

    2016-10-07

    We show that inflation can naturally occur at a finite temperature T>H that is sustained by dissipative effects, when the inflaton field corresponds to a pseudo Nambu-Goldstone boson of a broken gauge symmetry. Similar to the Little Higgs scenarios for electroweak symmetry breaking, the flatness of the inflaton potential is protected against both quadratic divergences and the leading thermal corrections. We show that, nevertheless, nonlocal dissipative effects are naturally present and are able to sustain a nearly thermal bath of light particles despite the accelerated expansion of the Universe. As an example, we discuss the dynamics of chaotic warm inflation with a quartic potential and show that the associated observational predictions are in very good agreement with the latest Planck results. This model constitutes the first realization of warm inflation requiring only a small number of fields; in particular, the inflaton is directly coupled to just two light fields.

  13. Greenhouse warming still coming

    SciTech Connect

    Kerr, R.A.

    1986-05-02

    The growing store of carbon dioxide in the earth's atmosphere from the burning of fossil fuels and deforestation is a far larger and more pervasive problem than acid rain. The predictions of the latest models that have been applied to the problem, called GCM-mixed-layer ocean models, predict a global temperature increase between 3.5 and 4.2 degrees Celsius. They predict that the warming will be larger near the poles than near the equator. They also predict increases and decreases in precipitation depending on location, the largest changes being between 30/sup 0/N and 30/sup 0/S. If CO/sub 2/ and trace gas concentrations continue to rise as projected and model calculations are essentially correct, the increasing global scale warming should become much more evident over the next few decades. 1 figure.

  14. Warm Little Inflaton

    NASA Astrophysics Data System (ADS)

    Bastero-Gil, Mar; Berera, Arjun; Ramos, Rudnei O.; Rosa, João G.

    2016-10-01

    We show that inflation can naturally occur at a finite temperature T >H that is sustained by dissipative effects, when the inflaton field corresponds to a pseudo Nambu-Goldstone boson of a broken gauge symmetry. Similar to the Little Higgs scenarios for electroweak symmetry breaking, the flatness of the inflaton potential is protected against both quadratic divergences and the leading thermal corrections. We show that, nevertheless, nonlocal dissipative effects are naturally present and are able to sustain a nearly thermal bath of light particles despite the accelerated expansion of the Universe. As an example, we discuss the dynamics of chaotic warm inflation with a quartic potential and show that the associated observational predictions are in very good agreement with the latest Planck results. This model constitutes the first realization of warm inflation requiring only a small number of fields; in particular, the inflaton is directly coupled to just two light fields.

  15. Military Implications of Global Warming.

    DTIC Science & Technology

    2007-11-02

    U.S. environmental issues also have important global implications. This paper analyzes current U.S. Policy as it pertains to global warming and climate...for military involvement to reduce global warming . Global warming and other environmental issues are important to the U.S. military. As the United

  16. Global Warming And Meltwater

    NASA Astrophysics Data System (ADS)

    Bratu, S.

    2012-04-01

    In order to find new approaches and new ideas for my students to appreciate the importance of science in their daily life, I proposed a theme for them to debate. They had to search for global warming information and illustrations in the media, and discuss the articles they found in the classroom. This task inspired them to search for new information about this important and timely theme in science. I informed my students that all the best information about global warming and meltwater they found would be used in a poster that would help us to update the knowledge base of the Physics laboratory. I guided them to choose the most eloquent images and significant information. Searching and working to create this poster, the students arrived to better appreciate the importance of science in their daily life and to critically evaluate scientific information transmitted via the media. In the poster we created, one can find images, photos and diagrams and some interesting information: Global warming refers to the rising average temperature of the Earth's atmosphere and oceans and its projected evolution. In the last 100 years, the Earth's average surface temperature increased by about 0.8 °C with about two thirds of the increase occurring over just the last three decades. Warming of the climate system is unequivocal, and scientists are more than 90% certain most of it is caused by increasing concentrations of greenhouse gases produced by human activities such as deforestation and burning fossil fuel. They indicate that during the 21st century the global surface temperature is likely to rise a further 1.1 to 2.9 °C for the lowest emissions scenario and 2.4 to 6.4 °C for the highest predictions. An increase in global temperature will cause sea levels to rise and will change the amount and pattern of precipitation, and potentially result in expansion of subtropical deserts. Warming is expected to be strongest in the Arctic and would be associated with continuing decrease of

  17. Global warming - A reduced threat

    SciTech Connect

    Michaels, P.J.; Stooksbury, D.E. )

    1992-10-01

    Issues associated with global warming are analyzed focusing on global and hemispheric temperature histories and trace gas concentrations; artificial warming from urban heat islands; high-latitude and diurnal temperatures; recent climate models; direct effects on vegetation of an increase in carbon dioxide; and compensatory cooling from other industrial products. Data obtained indicate that anthropogenerated sulfate emissions are mitigating some of the warming, and that increased cloudiness as a result of these emissions will further enhance night, rather than day, warming. It is noted that the sulfate emissions are not sufficient to explain all of the night warming. The sensitivity of climate to anthropogenerated aerosols, and the general lack of previously predicted warming, could drastically alter the debate on global warming in favor of less expensive policies. 61 refs.

  18. Warm climate surprises

    SciTech Connect

    Overpeck, J.T.

    1996-03-29

    Over the last decade, paleoclimatic data from ice cores and sediments have shown that the climate system is capable of switching between significantly different modes, suggesting that climatic surprises may lie ahead. Most attention in the growing area of abrupt climatic change research continues to be focused on large changes observed during glacial periods. The weight of paleoclimatic evidence now suggests that conforting conclusions of benign warm climate variability may be incorrect. The article goes on to discuss the evidence for this. 17 refs.

  19. FLATs: Warming Up

    NASA Astrophysics Data System (ADS)

    Calzetti, Daniela

    1997-07-01

    The purpose of this proposal is to monitor the flat fields during the interval between the end of science observations and the exhaustion of cryogen and subsequent warming of the dewar to > 100K. These flats will provide a monitor for particulate comtamination {GROT} and detector lateral position {from the coronagraphic spot and FDA vignetting}. They will provide some measure of relative {flat field} and absolute QE variation as a function of temperature. When stars are visible they might provide a limited degree of focus determination.

  20. FLATs: Warming Up - continuation

    NASA Astrophysics Data System (ADS)

    Calzetti, Daniela

    1997-07-01

    The purpose of this proposal is to monitor the flat fields during the interval between the end of science observations and the exhaustion of cryogen and subsequent warming of the dewar to > 100K. These flats will provide a monitor for particulate comtamination {GROT} and detector lateral position {from the coronagraphic spot and FDA vignetting}. They will provide some measure of relative {flat field} and absolute QE variation as a function of temperature. When stars are visible they might provide a limited degree of focus determination.

  1. Is Global Warming Accelerating?

    NASA Astrophysics Data System (ADS)

    Shukla, J.; Delsole, T. M.; Tippett, M. K.

    2009-12-01

    A global pattern that fluctuates naturally on decadal time scales is identified in climate simulations and observations. This newly discovered component, called the Global Multidecadal Oscillation (GMO), is related to the Atlantic Meridional Oscillation and shown to account for a substantial fraction of decadal fluctuations in the observed global average sea surface temperature. IPCC-class climate models generally underestimate the variance of the GMO, and hence underestimate the decadal fluctuations due to this component of natural variability. Decomposing observed sea surface temperature into a component due to anthropogenic and natural radiative forcing plus the GMO, reveals that most multidecadal fluctuations in the observed global average sea surface temperature can be accounted for by these two components alone. The fact that the GMO varies naturally on multidecadal time scales implies that it can be predicted with some skill on decadal time scales, which provides a scientific rationale for decadal predictions. Furthermore, the GMO is shown to account for about half of the warming in the last 25 years and hence a substantial fraction of the recent acceleration in the rate of increase in global average sea surface temperature. Nevertheless, in terms of the global average “well-observed” sea surface temperature, the GMO can account for only about 0.1° C in transient, decadal-scale fluctuations, not the century-long 1° C warming that has been observed during the twentieth century.

  2. Warm up II: performance changes following active warm up and how to structure the warm up.

    PubMed

    Bishop, David

    2003-01-01

    While warm up is considered to be essential for optimum performance, there is little scientific evidence supporting its effectiveness in many situations. As a result, warm-up procedures are usually based on the trial and error experience of the athlete or coach, rather than on scientific study. Summarising the findings of the many warm-up studies conducted over the years is difficult. Many of the earlier studies were poorly controlled, contained few study participants and often omitted statistical analyses. Furthermore, over the years, warm up protocols consisting of different types (e.g. active, passive, specific) and structures (e.g. varied intensity, duration and recovery) have been used. Finally, while many studies have investigated the physiological responses to warm up, relatively few studies have reported changes in performance following warm up. The first part of this review critically analyses reported changes in performance following various active warm-up protocols. While there is a scarcity of well-controlled studies with large subject numbers and appropriate statistical analyses, a number of conclusions can be drawn regarding the effects of active warm up on performance. Active warm up tends to result in slightly larger improvements in short-term performance (<10 seconds) than those achieved by passive heating alone. However, short-term performance may be impaired if the warm-up protocol is too intense or does not allow sufficient recovery, and results in a decreased availability of high-energy phosphates before commencing the task. Active warm up appears to improve both long-term (>/=5 minutes) and intermediate performance (>10 seconds, but <5 minutes) if it allows the athlete to begin the subsequent task in a relatively non-fatigued state, but with an elevated baseline oxygen consumption (VO(2)). While active warm up has been reported to improve endurance performance, it may have a detrimental effect on endurance performance if it causes a

  3. Global Warming on Triton

    NASA Technical Reports Server (NTRS)

    Elliot, J. L.; Hammel, H. B.; Wasserman, L. H.; Franz, O. G.; McDonald, S. W.; Person, M. J.; Olkin, C. B.; Dunham, E. J.; Spencer, J. R.; Stansberry, J. A.; Buie, M. W.; Pasachoff, J. M.; Babcock, B. A.; McConnochie, T. H.

    1998-01-01

    Triton, Neptune's largest moon, has been predicted to undergo significant seasonal changes that would reveal themselves as changes in its mean frost temperature. But whether this temperature should at the present time be increasing, decreasing or constant depends on a number of parameters (such as the thermal properties of the surface, and frost migration patterns) that are unknown. Here we report observations of a recent stellar occultation by Triton which, when combined with earlier results, show that Triton has undergone a period of global warming since 1989. Our most conservative estimates of the rate of temperature and surface-pressure increase during this period imply that the atmosphere is doubling in bulk every 10 years, significantly faster than predicted by any published frost model for Triton. Our result suggests that permanent polar caps on Triton play a c dominant role in regulating seasonal atmospheric changes. Similar processes should also be active on Pluto.

  4. Warm waters, bleached corals

    SciTech Connect

    Roberts, L.

    1990-10-12

    Two researchers, Tom Goreau of the Discovery Laboratory in Jamaica and Raymond Hayes of Howard University, claim that they have evidence that nearly clinches the temperature connection to the bleached corals in the Caribbean and that the coral bleaching is an indication of Greenhouse warming. The incidents of scattered bleaching of corals, which have been reported for decades, are increasing in both intensity and frequency. The researchers based their theory on increased temperature of the seas measured by satellites. However, some other scientists feel that the satellites measure the temperature of only the top few millimeters of the water and that since corals lie on reefs perhaps 60 to 100 feet below the ocean surface, the elevated temperatures are not significant.

  5. Global warming challenge

    SciTech Connect

    Hengeveld, H. )

    1994-11-01

    Global warming will necessitate significant adjustments in Canadian society and its economy. In 1979, the Canadian federal government created its Canadian Climate Program (CCP) in collaboration with other agencies, institutions, and individuals. It sought to coordinate national efforts to understand global and regional climate, and to promote better use of the emerging knowledge. Much of the CCP-coordinated research into sources and sinks of greenhouse gases interfaces with other national and international programs. Other researchers have become involved in the Northern Wetlands Study, a cooperative United States-Canada initiative to understand the role of huge northern bogs and muskegs in the carbon cycle. Because of the need to understand how the whole, linked climate system works, climate modeling emerged as a key focus of current research. 35 refs., 4 figs.

  6. Warm dark matter

    SciTech Connect

    Horiuchi, Shunsaku

    2016-06-21

    The cold dark matter paradigm has been extremely successful in explaining the large-scale structure of the Universe. However, it continues to face issues when confronted by observations on sub-Galactic scales. A major caveat, now being addressed, has been the incomplete treatment of baryon physics. We first summarize the small-scale issues surrounding cold dark matter and discuss the solutions explored by modern state-of-the-art numerical simulations including treatment of baryonic physics. We identify the too big to fail in field galaxies as among the best targets to study modifications to dark matter, and discuss the particular connection with sterile neutrino warm dark matter. We also discuss how the recently detected anomalous 3.55 keV X-ray lines, when interpreted as sterile neutrino dark matter decay, provide a very good description of small-scale observations of the Local Group.

  7. Competent and Warm?

    PubMed

    Hansen, Karolina; Rakić, Tamara; Steffens, Melanie C

    2017-01-01

    Most research on ethnicity has focused on visual cues. However, accents are strong social cues that can match or contradict visual cues. We examined understudied reactions to people whose one cue suggests one ethnicity, whereas the other cue contradicts it. In an experiment conducted in Germany, job candidates spoke with an accent either congruent or incongruent with their (German or Turkish) appearance. Based on ethnolinguistic identity theory, we predicted that accents would be strong cues for categorization and evaluation. Based on expectancy violations theory we expected that incongruent targets would be evaluated more extremely than congruent targets. Both predictions were confirmed: accents strongly influenced perceptions and Turkish-looking German-accented targets were perceived as most competent of all targets (and additionally most warm). The findings show that bringing together visual and auditory information yields a more complete picture of the processes underlying impression formation.

  8. Interacting warm dark matter

    SciTech Connect

    Cruz, Norman; Palma, Guillermo; Zambrano, David; Avelino, Arturo E-mail: guillermo.palma@usach.cl E-mail: avelino@fisica.ugto.mx

    2013-05-01

    We explore a cosmological model composed by a dark matter fluid interacting with a dark energy fluid. The interaction term has the non-linear λρ{sub m}{sup α}ρ{sub e}{sup β} form, where ρ{sub m} and ρ{sub e} are the energy densities of the dark matter and dark energy, respectively. The parameters α and β are in principle not constrained to take any particular values, and were estimated from observations. We perform an analytical study of the evolution equations, finding the fixed points and their stability properties in order to characterize suitable physical regions in the phase space of the dark matter and dark energy densities. The constants (λ,α,β) as well as w{sub m} and w{sub e} of the EoS of dark matter and dark energy respectively, were estimated using the cosmological observations of the type Ia supernovae and the Hubble expansion rate H(z) data sets. We find that the best estimated values for the free parameters of the model correspond to a warm dark matter interacting with a phantom dark energy component, with a well goodness-of-fit to data. However, using the Bayesian Information Criterion (BIC) we find that this model is overcame by a warm dark matter – phantom dark energy model without interaction, as well as by the ΛCDM model. We find also a large dispersion on the best estimated values of the (λ,α,β) parameters, so even if we are not able to set strong constraints on their values, given the goodness-of-fit to data of the model, we find that a large variety of theirs values are well compatible with the observational data used.

  9. Local warming: daily temperature change influences belief in global warming.

    PubMed

    Li, Ye; Johnson, Eric J; Zaval, Lisa

    2011-04-01

    Although people are quite aware of global warming, their beliefs about it may be malleable; specifically, their beliefs may be constructed in response to questions about global warming. Beliefs may reflect irrelevant but salient information, such as the current day's temperature. This replacement of a more complex, less easily accessed judgment with a simple, more accessible one is known as attribute substitution. In three studies, we asked residents of the United States and Australia to report their opinions about global warming and whether the temperature on the day of the study was warmer or cooler than usual. Respondents who thought that day was warmer than usual believed more in and had greater concern about global warming than did respondents who thought that day was colder than usual. They also donated more money to a global-warming charity if they thought that day seemed warmer than usual. We used instrumental variable regression to rule out some alternative explanations.

  10. Committed warming inferred from observations

    NASA Astrophysics Data System (ADS)

    Mauritsen, Thorsten; Pincus, Robert

    2017-09-01

    Due to the lifetime of CO2, the thermal inertia of the oceans, and the temporary impacts of short-lived aerosols and reactive greenhouse gases, the Earth’s climate is not equilibrated with anthropogenic forcing. As a result, even if fossil-fuel emissions were to suddenly cease, some level of committed warming is expected due to past emissions as studied previously using climate models. Here, we provide an observational-based quantification of this committed warming using the instrument record of global-mean warming, recently improved estimates of Earth’s energy imbalance, and estimates of radiative forcing from the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Compared with pre-industrial levels, we find a committed warming of 1.5 K (0.9-3.6, 5th-95th percentile) at equilibrium, and of 1.3 K (0.9-2.3) within this century. However, when assuming that ocean carbon uptake cancels remnant greenhouse gas-induced warming on centennial timescales, committed warming is reduced to 1.1 K (0.7-1.8). In the latter case there is a 13% risk that committed warming already exceeds the 1.5 K target set in Paris. Regular updates of these observationally constrained committed warming estimates, although simplistic, can provide transparent guidance as uncertainty regarding transient climate sensitivity inevitably narrows and the understanding of the limitations of the framework is advanced.

  11. Blodgett Forest Warming Experiment 1

    DOE Data Explorer

    Pries, Caitlin Hicks (ORCID:0000000308132211); Castanha, Cristina; Porras, Rachel; Torn, Margaret

    2017-03-24

    Carbon stocks and density fractions from soil pits used to characterize soils of the Blodgett warming experiment as well as gas well CO2, 13C, and 14C data from experimental plots. The experiment consisted of 3 control and heated plot pairs. The heated plots are warmed +4°C above the control from 10 to 100 cm.

  12. Consistency of warm k -inflation

    NASA Astrophysics Data System (ADS)

    Peng, Zhi-Peng; Yu, Jia-Ning; Zhu, Jian-Yang; Zhang, Xiao-Min

    2016-11-01

    We extend k -inflation which is a type of kinetically driven inflationary model under the standard inflationary scenario to a possible warm inflationary scenario. The dynamical equations of this warm k -inflation model are obtained. We rewrite the slow-roll parameters which are different from the usual potential driven inflationary models and perform a linear stability analysis to give the proper slow-roll conditions in warm k -inflation. Two cases, a power-law kinetic function and an exponential kinetic function, are studied, when the dissipative coefficient Γ =Γ0 and Γ =Γ (ϕ ), respectively. A proper number of e-folds is obtained in both concrete cases of warm k -inflation. We find a constant dissipative coefficient (Γ =Γ0) is not a workable choice for these two cases while the two cases with Γ =Γ (ϕ ) are self-consistent warm inflationary models.

  13. Policy implications of greenhouse warming

    NASA Astrophysics Data System (ADS)

    Coppock, Rob

    1992-03-01

    A study panel of the National Academy of Sciences, National Academy of Engineering, and Institute of Medicine recently issued the report Policy Implications of Greenhouse Warming. That report examined relevant scientific knowldeg and evidence about the potential of greenhouse warming, and assayed actions that could slow the onset of warming (mitigation policies) or help human and natural systems of plants and animals adapt to climatic changes (adaptation policies). The panel found that, even given the considerable uncertainties knowledge of the relevant phenomena, greenhouse warming poses a threat sufficient to merit prompt action. People in this country could probably adapt to the changes likely to accompany greenhouse warming. The costs, however, could be substantial. Investment in mitigation acts as insurance protection against the great uncertainties and the possibility of dramatic surprises. The panel found mitigation options that could reduce U.S. emissions by an estimated 10 to 40 percent at modest cost.

  14. Explaining Warm Coronal Loops

    NASA Technical Reports Server (NTRS)

    Klimchuk, James A.; Karpen, Judy T.; Patsourakos, Spiros

    2008-01-01

    One of the great mysteries of coronal physics that has come to light in the last few years is the discovery that warn (- 1 INK) coronal loops are much denser than expected for quasi-static equilibrium. Both the excess densities and relatively long lifetimes of the loops can be explained with bundles of unresolved strands that are heated impulsively to very high temperatures. Since neighboring strands are at different stages of cooling, the composite loop bundle is multi-thermal, with the distribution of temperatures depending on the details of the "nanoflare storm." Emission hotter than 2 MK is predicted, but it is not clear that such emission is always observed. We consider two possible explanations for the existence of over-dense warm loops without corresponding hot emission: (1) loops are bundles of nanoflare heated strands, but a significant fraction of the nanoflare energy takes the form of a nonthermal electron beam rather then direct plasma heating; (2) loops are bundles of strands that undergo thermal nonequilibrium that results when steady heating is sufficiently concentrated near the footpoints. We present numerical hydro simulations of both of these possibilities and explore the observational consequences, including the production of hard X-ray emission and absorption by cool material in the corona.

  15. Defining Sudden Stratospheric Warmings

    NASA Astrophysics Data System (ADS)

    Butler, Amy; Seidel, Dian; Hardiman, Steven; Butchart, Neal; Birner, Thomas; Match, Aaron

    2015-04-01

    The general form of the definition for Sudden Stratospheric Warmings (SSWs) is largely agreed to be a reversal of the temperature gradient and of the zonal circulation polewards of 60° latitude at the 10 hPa level, as developed by the World Meteorological Organization (WMO) in the 1960s and 1970s. However, the details of the definition and its calculation are ambiguous, resulting in inconsistent classifications of SSW events. These discrepancies are problematic for understanding the observed frequency and statistical relationships with SSWs, and for maintaining a robust metric with which to assess wintertime stratospheric variability in observations and climate models. To provide a basis for community-wide discussion, we examine how the SSW definition has changed over time and how sensitive the detection of SSWs is to the definition used. We argue that the general form of the SSW definition should be clarified to ensure that it serves current research and forecasting purposes, and propose possible ways to update the definition.

  16. Explaining Warm Coronal Loops

    NASA Technical Reports Server (NTRS)

    Klimchuk, James A.; Karpen, Judy T.; Patsourakos, Spiros

    2008-01-01

    One of the great mysteries of coronal physics that has come to light in the last few years is the discovery that warn (- 1 INK) coronal loops are much denser than expected for quasi-static equilibrium. Both the excess densities and relatively long lifetimes of the loops can be explained with bundles of unresolved strands that are heated impulsively to very high temperatures. Since neighboring strands are at different stages of cooling, the composite loop bundle is multi-thermal, with the distribution of temperatures depending on the details of the "nanoflare storm." Emission hotter than 2 MK is predicted, but it is not clear that such emission is always observed. We consider two possible explanations for the existence of over-dense warm loops without corresponding hot emission: (1) loops are bundles of nanoflare heated strands, but a significant fraction of the nanoflare energy takes the form of a nonthermal electron beam rather then direct plasma heating; (2) loops are bundles of strands that undergo thermal nonequilibrium that results when steady heating is sufficiently concentrated near the footpoints. We present numerical hydro simulations of both of these possibilities and explore the observational consequences, including the production of hard X-ray emission and absorption by cool material in the corona.

  17. Warm dense crystallography

    NASA Astrophysics Data System (ADS)

    Valenza, Ryan A.; Seidler, Gerald T.

    2016-03-01

    The intense femtosecond-scale pulses from x-ray free electron lasers (XFELs) are able to create and interrogate interesting states of matter characterized by long-lived nonequilibrium semicore or core electron occupancies or by the heating of dense phases via the relaxation cascade initiated by the photoelectric effect. We address here the latter case of "warm dense matter" (WDM) and investigate the observable consequences of x-ray heating of the electronic degrees of freedom in crystalline systems. We report temperature-dependent density functional theory calculations for the x-ray diffraction from crystalline LiF, graphite, diamond, and Be. We find testable, strong signatures of condensed-phase effects that emphasize the importance of wide-angle scattering to study nonequilibrium states. These results also suggest that the reorganization of the valence electron density at eV-scale temperatures presents a confounding factor to achieving atomic resolution in macromolecular serial femtosecond crystallography (SFX) studies at XFELs, as performed under the "diffract before destroy" paradigm.

  18. Recent warming of lake Kivu.

    PubMed

    Katsev, Sergei; Aaberg, Arthur A; Crowe, Sean A; Hecky, Robert E

    2014-01-01

    Lake Kivu in East Africa has gained notoriety for its prodigious amounts of dissolved methane and dangers of limnic eruption. Being meromictic, it is also expected to accumulate heat due to rising regional air temperatures. To investigate the warming trend and distinguish between atmospheric and geothermal heating sources, we compiled historical temperature data, performed measurements with logging instruments, and simulated heat propagation. We also performed isotopic analyses of water from the lake's main basin and isolated Kabuno Bay. The results reveal that the lake surface is warming at the rate of 0.12°C per decade, which matches the warming rates in other East African lakes. Temperatures increase throughout the entire water column. Though warming is strongest near the surface, warming rates in the deep waters cannot be accounted for solely by propagation of atmospheric heat at presently assumed rates of vertical mixing. Unless the transport rates are significantly higher than presently believed, this indicates significant contributions from subterranean heat sources. Temperature time series in the deep monimolimnion suggest evidence of convection. The progressive deepening of the depth of temperature minimum in the water column is expected to accelerate the warming in deeper waters. The warming trend, however, is unlikely to strongly affect the physical stability of the lake, which depends primarily on salinity gradient.

  19. Recent Warming of Lake Kivu

    PubMed Central

    Katsev, Sergei; Aaberg, Arthur A.; Crowe, Sean A.; Hecky, Robert E.

    2014-01-01

    Lake Kivu in East Africa has gained notoriety for its prodigious amounts of dissolved methane and dangers of limnic eruption. Being meromictic, it is also expected to accumulate heat due to rising regional air temperatures. To investigate the warming trend and distinguish between atmospheric and geothermal heating sources, we compiled historical temperature data, performed measurements with logging instruments, and simulated heat propagation. We also performed isotopic analyses of water from the lake's main basin and isolated Kabuno Bay. The results reveal that the lake surface is warming at the rate of 0.12°C per decade, which matches the warming rates in other East African lakes. Temperatures increase throughout the entire water column. Though warming is strongest near the surface, warming rates in the deep waters cannot be accounted for solely by propagation of atmospheric heat at presently assumed rates of vertical mixing. Unless the transport rates are significantly higher than presently believed, this indicates significant contributions from subterranean heat sources. Temperature time series in the deep monimolimnion suggest evidence of convection. The progressive deepening of the depth of temperature minimum in the water column is expected to accelerate the warming in deeper waters. The warming trend, however, is unlikely to strongly affect the physical stability of the lake, which depends primarily on salinity gradient. PMID:25295730

  20. How the West Was Warmed

    NASA Astrophysics Data System (ADS)

    Hoerling, M.; Eischeid, J.

    2006-05-01

    Is the West getting warmer? To be sure, the summer of 2005 was one of record heat in the West, and recent period of western US drought during 1998-2004 was also accompanied by unusual warmth. But warm conditions accompanied the Dust Bowl era of the 1930s and the 1950s. The question remains open whether recent western warming has been part of a externally forced climate trend, or whether other processes have been at play like urbanization or the inherent natural fluctuations of climate paterns? We perform analysis of the Fourth Assessment coupled ocean-atmosphere models for the period 1895-2005, together with atmospheric general circulation model experiments. These reveal that the recent warming of the West has very likely been a consequence of increasing greenhouse gases. In fact, no single member of 40 availabl GHG-forced simulations failed to warm the West during the past century. We further show that a warming of the tropical oceanic warm pool regions, itself a greenhouse gas forced response, has been a major contributor to the warming of the West since 1970.

  1. Density fluctuations from warm inflation

    SciTech Connect

    Graham, Chris; Moss, Ian G. E-mail: ian.moss@ncl.ac.uk

    2009-07-01

    Thermal fluctuations provide the main source of large scale density perturbations in warm inflationary models of the early universe. For the first time, general results are obtained for the power spectrum in the case when the friction coefficient in the inflaton equation of motion depends on temperature. A large increase in the amplitude of perturbations occurs when the friction coefficient increases with temperature. This has to be taken into account when constructing models of warm inflation. New results are also given for the thermal fluctuations in the weak regime of warm inflation when the friction coefficient is relatively small.

  2. Amplified Arctic warming by phytoplankton under greenhouse warming.

    PubMed

    Park, Jong-Yeon; Kug, Jong-Seong; Bader, Jürgen; Rolph, Rebecca; Kwon, Minho

    2015-05-12

    Phytoplankton have attracted increasing attention in climate science due to their impacts on climate systems. A new generation of climate models can now provide estimates of future climate change, considering the biological feedbacks through the development of the coupled physical-ecosystem model. Here we present the geophysical impact of phytoplankton, which is often overlooked in future climate projections. A suite of future warming experiments using a fully coupled ocean-atmosphere model that interacts with a marine ecosystem model reveals that the future phytoplankton change influenced by greenhouse warming can amplify Arctic surface warming considerably. The warming-induced sea ice melting and the corresponding increase in shortwave radiation penetrating into the ocean both result in a longer phytoplankton growing season in the Arctic. In turn, the increase in Arctic phytoplankton warms the ocean surface layer through direct biological heating, triggering additional positive feedbacks in the Arctic, and consequently intensifying the Arctic warming further. Our results establish the presence of marine phytoplankton as an important potential driver of the future Arctic climate changes.

  3. Amplified Arctic warming by phytoplankton under greenhouse warming

    PubMed Central

    Park, Jong-Yeon; Kug, Jong-Seong; Bader, Jürgen; Rolph, Rebecca; Kwon, Minho

    2015-01-01

    Phytoplankton have attracted increasing attention in climate science due to their impacts on climate systems. A new generation of climate models can now provide estimates of future climate change, considering the biological feedbacks through the development of the coupled physical–ecosystem model. Here we present the geophysical impact of phytoplankton, which is often overlooked in future climate projections. A suite of future warming experiments using a fully coupled ocean−atmosphere model that interacts with a marine ecosystem model reveals that the future phytoplankton change influenced by greenhouse warming can amplify Arctic surface warming considerably. The warming-induced sea ice melting and the corresponding increase in shortwave radiation penetrating into the ocean both result in a longer phytoplankton growing season in the Arctic. In turn, the increase in Arctic phytoplankton warms the ocean surface layer through direct biological heating, triggering additional positive feedbacks in the Arctic, and consequently intensifying the Arctic warming further. Our results establish the presence of marine phytoplankton as an important potential driver of the future Arctic climate changes. PMID:25902494

  4. Weird Warm Spot on Exoplanet

    NASA Image and Video Library

    2010-10-19

    This frame from an animation based on NASA Spitzer Space Telescope data illustrates an unexpected warm spot on the surface of a gaseous exoplanet.The bright orange patches are the hottest part of the planet.

  5. Weird Warm Spot on Exoplanet

    NASA Image and Video Library

    This animation illustrates an unexpected warm spot on the surface of a gaseous exoplanet. NASA's Spitzer Space Telescope discovered that the hottest part of the planet, shown here as bright, orange...

  6. Global warming potentials of Hydrofluoroethers.

    PubMed

    Blowers, Paul; Moline, Dena Marie; Tetrault, Kyle Franklin; Wheeler, R'nld Ruth; Tuchawena, Shane Lee

    2008-02-15

    Global warming potentials are estimated for hydrofluoroethers, which are an emerging class of compounds for industrial use. Comparisons are made to the limited data previously available before observations about molecular design are discussed. We quantify how molecular structure can be manipulated to reduce environmental impacts due to global warming. We further highlight the need for additional research on this class of compounds so environmental performance can be assessed for green design.

  7. The Great Warming Brian Fagan

    NASA Astrophysics Data System (ADS)

    Fagan, B. M.

    2010-12-01

    The Great Warming is a journey back to the world of a thousand years ago, to the Medieval Warm Period. Five centuries of irregular warming from 800 to 1250 had beneficial effects in Europe and the North Atlantic, but brought prolonged droughts to much of the Americas and lands affected by the South Asian monsoon. The book describes these impacts of warming on medieval European societies, as well as the Norse and the Inuit of the far north, then analyzes the impact of harsh, lengthy droughts on hunting societies in western North America and the Ancestral Pueblo farmers of Chaco Canyon, New Mexico. These peoples reacted to drought by relocating entire communities. The Maya civilization was much more vulnerable that small-scale hunter-gatherer societies and subsistence farmers in North America. Maya rulers created huge water storage facilities, but their civilization partially collapsed under the stress of repeated multiyear droughts, while the Chimu lords of coastal Peru adapted with sophisticated irrigation works. The climatic villain was prolonged, cool La Niñalike conditions in the Pacific, which caused droughts from Venezuela to East Asia, and as far west as East Africa. The Great Warming argues that the warm centuries brought savage drought to much of humanity, from China to Peru. It also argues that drought is one of the most dangerous elements in today’s humanly created global warming, often ignored by preoccupied commentators, but with the potential to cause over a billion people to starve. Finally, I use the book to discuss the issues and problems of communicating multidisciplinary science to the general public.

  8. Active Movement Warm-Up Routines

    ERIC Educational Resources Information Center

    Walter, Teri; Quint, Ashleigh; Fischer, Kim; Kiger, Joy

    2011-01-01

    This article presents warm-ups that are designed to physiologically and psychologically prepare students for vigorous physical activity. An active movement warm-up routine is made up of three parts: (1) active warm-up movement exercises, (2) general preparation, and (3) the energy system. These warm-up routines can be used with all grade levels…

  9. Warm Up to a Good Sound

    ERIC Educational Resources Information Center

    Tovey, David C.

    1977-01-01

    Most choral directors in schools today have been exposed to a variety of warm-up procedures. Yet, many do not use the warm-up time effectively as possible. Considers the factors appropriate to a warm-up exercise and three basic warm-up categories. (Author/RK)

  10. Active Movement Warm-Up Routines

    ERIC Educational Resources Information Center

    Walter, Teri; Quint, Ashleigh; Fischer, Kim; Kiger, Joy

    2011-01-01

    This article presents warm-ups that are designed to physiologically and psychologically prepare students for vigorous physical activity. An active movement warm-up routine is made up of three parts: (1) active warm-up movement exercises, (2) general preparation, and (3) the energy system. These warm-up routines can be used with all grade levels…

  11. How warm days increase belief in global warming

    NASA Astrophysics Data System (ADS)

    Zaval, Lisa; Keenan, Elizabeth A.; Johnson, Eric J.; Weber, Elke U.

    2014-02-01

    Climate change judgements can depend on whether today seems warmer or colder than usual, termed the local warming effect. Although previous research has demonstrated that this effect occurs, studies have yet to explain why or how temperature abnormalities influence global warming attitudes. A better understanding of the underlying psychology of this effect can help explain the public's reaction to climate change and inform approaches used to communicate the phenomenon. Across five studies, we find evidence of attribute substitution, whereby individuals use less relevant but available information (for example, today's temperature) in place of more diagnostic but less accessible information (for example, global climate change patterns) when making judgements. Moreover, we rule out alternative hypotheses involving climate change labelling and lay mental models. Ultimately, we show that present temperature abnormalities are given undue weight and lead to an overestimation of the frequency of similar past events, thereby increasing belief in and concern for global warming.

  12. Distinguishing warming-induced drought from drought-induced warming

    NASA Astrophysics Data System (ADS)

    Roderick, M. L.; Yin, D.

    2015-12-01

    It is usually observed that temperatures, especially maximum temperatures are higher during drought. A very widely held public perception is that the increase in temperature is a cause of drought. This represents the warming-induced drought scenario. However, the agricultural and hydrologic scientific communities have a very different interpretation with drought being the cause of increasing temperature. In essence, those communities assume the warming is a surface feedback and their interpretation is for drought-induced warming. This is a classic cause-effect problem that has resisted definitive explanation due to the lack of radiative observations at suitable spatial and temporal scales. In this presentation we first summarise the observations and then use theory to untangle the cause-effect relationships that underlie the competing interpretations. We then show how satellite data (CERES, NASA) can be used to disentangle the cause-effect relations.

  13. Global warming and infectious disease.

    PubMed

    Khasnis, Atul A; Nettleman, Mary D

    2005-01-01

    Global warming has serious implications for all aspects of human life, including infectious diseases. The effect of global warming depends on the complex interaction between the human host population and the causative infectious agent. From the human standpoint, changes in the environment may trigger human migration, causing disease patterns to shift. Crop failures and famine may reduce host resistance to infections. Disease transmission may be enhanced through the scarcity and contamination of potable water sources. Importantly, significant economic and political stresses may damage the existing public health infrastructure, leaving mankind poorly prepared for unexpected epidemics. Global warming will certainly affect the abundance and distribution of disease vectors. Altitudes that are currently too cool to sustain vectors will become more conducive to them. Some vector populations may expand into new geographic areas, whereas others may disappear. Malaria, dengue, plague, and viruses causing encephalitic syndromes are among the many vector-borne diseases likely to be affected. Some models suggest that vector-borne diseases will become more common as the earth warms, although caution is needed in interpreting these predictions. Clearly, global warming will cause changes in the epidemiology of infectious diseases. The ability of mankind to react or adapt is dependent upon the magnitude and speed of the change. The outcome will also depend on our ability to recognize epidemics early, to contain them effectively, to provide appropriate treatment, and to commit resources to prevention and research.

  14. Cosmic Rays and Global Warming

    SciTech Connect

    Sloan, T.; Wolfendale, A. W.

    2008-01-24

    Some workers have claimed that the observed temporal correlations of (low level) terrestrial cloud cover with the cosmic ray intensity changes, due to solar modulation, are causal. The possibility arises, therefore, of a connection between cosmic rays and Global Warming. If true, the implications would be very great. We have examined this claim in some detail. So far, we have not found any evidence in support and so our conclusions are to doubt it. From the absence of corroborative evidence we estimate that less than 15% at the 95% confidence level, of the 11-year cycle warming variations are due to cosmic rays and less than 2% of the warming over the last 43 years is due to this cause. The origin of the correlation itself is probably the cycle of solar irradiance although there is, as yet, no certainty.

  15. Global warming: trends and effects.

    PubMed

    Tickell, C

    1993-01-01

    As animals we have been a remarkably successful species; but also as animals we are vulnerable to environmental, in particular climate change. Such change is accelerating as a result of human activity, and global warming may already be taking place. Although we can foresee the trends, we cannot yet be specific about the results. Change usually proceeds by steps rather than gradients. But warming would probably include new risks to human health and contribute to an increase in human displacement. Of course climate change is only one among other complex problems facing human society, but it is closely related to them all, including population increase, environmental degradation and loss of biodiversity. We cannot prevent global warming but we can anticipate and mitigate some of its worst effects. Peoples and governments still need persuading of the need for action and of the magnitude of the issue at stake.

  16. [Passive nighttime warming (PNW) system, its design and warming effect].

    PubMed

    Chen, Jin; Yang, Fei; Zhang, Bin; Tian, Yun-lu; Dong, Wen-jun; Zhang, Wei-jian

    2010-09-01

    Based on the technique of passive nighttime warming (PNW), a convenient and energy-saving PNW facility was designed for a rice-wheat cropping system in Danyang, Jiangsu Province. The facility could guarantee 15.75 m2 effective sampling area, with a homogeneous amplitude of increased temperature, and making the nighttime canopy temperature during whole rice growth season increased averagely by 1.1 degrees C and the nighttime canopy temperature and 5 cm soil temperature during whole winter wheat growth period increased averagely by 1.3 degrees C and 0.8 degrees C, respectively. During the operation period of the facility, the variation trends of the canopy temperature and 5 cm soil temperature during the whole growth periods of rice and winter wheat in the warming plots were similar to those of the control. Though the facility slightly decreased the soil moisture content during winter wheat growth period, wheat growth was less impacted. The application of this facility in our main production areas of rice and winter wheat showed that the facility could advance the initial blossoming stages of rice and winter wheat averagely by 3 d and 5 d, respectively. In despite of the discrepancy in the warming effect among different regions and seasons, this energy-saving facility was reliable for the field research on crop responses to climate warming, when the homogeneity of increased temperature, the effective area, and the effects on crop growth period were taken into comprehensive consideration.

  17. Global warming at the summit

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    During the recent summit meeting between Russian President Vladimir Putin and U.S. President Bill Clinton, the two leaders reaffirmed their concerns about global warming and the need to continue to take actions to try to reduce the threat.In a June 4 joint statement, they stressed the need to develop flexibility mechanisms, including international emissions trading, under the Kyoto Protocol to the United Nations Framework Convention on Climate Change. They also noted that initiatives to reduce the risk of greenhouse warming, including specific mechanisms of the Kyoto Protocol, could potentially promote economic growth.

  18. Global Warming: Physics and Facts

    SciTech Connect

    Levi, B.G. ); Hafemeister, D. , Washington, DC ); Scribner, R. )

    1992-01-01

    This report contains papers on: A tutorial on global atmospheric energetics and the greenhouse effect; global climate models: what and how; comparison of general circulation models; climate and the earth's radiation budget; temperature and sea level change; short-term climate variability and predictions; the great ocean conveyor; trace gases in the atmosphere: temporal and spatial trends; the geochemical carbon cycle and the uptake of fossil fuel CO{sub 2}; forestry and global warming; the physical and policy linkages; policy implications of greenhouse warming; options for lowering US carbon dioxide emissions; options for reducing carbon dioxide emissions; and science and diplomacy: a new partnership to protect the environment.

  19. Global Warming: Physics and Facts

    SciTech Connect

    Levi, B.G.; Hafemeister, D.; Scribner, R.

    1992-05-01

    This report contains papers on: A tutorial on global atmospheric energetics and the greenhouse effect; global climate models: what and how; comparison of general circulation models; climate and the earth`s radiation budget; temperature and sea level change; short-term climate variability and predictions; the great ocean conveyor; trace gases in the atmosphere: temporal and spatial trends; the geochemical carbon cycle and the uptake of fossil fuel CO{sub 2}; forestry and global warming; the physical and policy linkages; policy implications of greenhouse warming; options for lowering US carbon dioxide emissions; options for reducing carbon dioxide emissions; and science and diplomacy: a new partnership to protect the environment.

  20. Warming up to solar energy

    SciTech Connect

    Biondo, B.

    1996-07-01

    Increasingly alarmed by threats to their financial security posed by an escalating number of weather-related catastrophes, major insurance companaies, particularly those in Europe and Asia, are starting to support a variety of measures that would slowe the production of grenhouse gases worlwide. As the insurance and banking industries turn their attention to global warming, investments in solar energy take on growing appeal.

  1. Equatorial refuge amid tropical warming

    NASA Astrophysics Data System (ADS)

    Karnauskas, Kristopher B.; Cohen, Anne L.

    2012-07-01

    Upwelling across the tropical Pacific Ocean is projected to weaken in accordance with a reduction of the atmospheric overturning circulation, enhancing the increase in sea surface temperature relative to other regions in response to greenhouse-gas forcing. In the central Pacific, home to one of the largest marine protected areas and fishery regions in the global tropics, sea surface temperatures are projected to increase by 2.8°C by the end of this century. Of critical concern is that marine protected areas may not provide refuge from the anticipated rate of large-scale warming, which could exceed the evolutionary capacity of coral and their symbionts to adapt. Combining high-resolution satellite measurements, an ensemble of global climate models and an eddy-resolving regional ocean circulation model, we show that warming and productivity decline around select Pacific islands will be mitigated by enhanced upwelling associated with a strengthening of the equatorial undercurrent. Enhanced topographic upwelling will act as a negative feedback, locally mitigating the surface warming. At the Gilbert Islands, the rate of warming will be reduced by 0.7+/-0.3°C or 25+/-9% per century, or an overall cooling effect comparable to the local anomaly for a typical El Niño, by the end of this century. As the equatorial undercurrent is dynamically constrained to the Equator, only a handful of coral reefs stand to benefit from this equatorial island effect. Nevertheless, those that do face a lower rate of warming, conferring a significant advantage over neighbouring reef systems. If realized, these predictions help to identify potential refuges for coral reef communities from anticipated climate changes of the twenty-first century.

  2. Medical aspects of global warming.

    PubMed

    Yoganathan, D; Rom, W N

    2001-08-01

    Global warming is caused by increased carbon dioxide (CO2)resulting in a greenhouse effect with enhanced warming of the earth. Measurements of CO2 show a steady increase over the past 30 years caused by the burning of fossil fuels and from the loss of natural CO2 sinks. A 100-year increase in global temperature by 0.3 to 0.6 degrees C is reflected in atmospheric warming, glacier shrinkage, and rising sea levels. Planetary ecosystem dynamics are being altered, challenging public health. It is predicted that morbidity and mortality will increase as a result of heat stress, as seen in recent heat waves in the U.S. Weather disaster effects will increase in number and magnitude, and both noninfectious and infectious diseases may flourish. A significant challenge will be the changes in life cycles of microbial species due to the warmer environs. Specific increases in incidence have been noted for vector-borne diseases, in addition to pulmonary findings, cardiovascular morbidity, neurological diseases, and occupational diseases. Warming can be demonstrated by the observed changes that have already occurred in the environment, particularly the thinning of polar ice caps. The United States Global Research Program has been established to coordinate research activities, which responds to issues deemed important by the United Nations Framework Convention on Climate Change. Research issues pertain to the scientific uncertainties in the greenhouse effect, temperature measurements at various atmospheric levels and latitudes, and impact on biota redistribution. The Kyoto Protocol has mandated specific solutions, e.g., a 7% reduction in CO2 levels within 10 years. Future recommendations involve supporting new technologies that are available to decrease emissions as well as understanding the role that occupational and environmental specialists have in global warming recognition. Copyright 2001 Wiley-Liss, Inc.

  3. Separating warming-induced drought from drought-induced warming

    NASA Astrophysics Data System (ADS)

    Roderick, Michael; Wolf, Sebastian; Yin, Dongqin

    2017-04-01

    A very widely held public perception is that increasing temperature is a cause of "drying" and drought. The atmospheric-focused meteorologic community has often assumed that the warmer temperatures increase evaporation and that this contributes to worsening drought via atmospheric demand. On the other hand, the agricultural and hydrologic scientific communities have a very different interpretation linked to water supply, with the lack of available water leading to reduced evaporation and enhanced surface warming. This is a classic chicken-or-the-egg problem that has resisted definitive explanation probably due to the lack of radiative observations at suitable spatial and temporal scales. Here we use recently released NASA CERES satellite radiation data to study the 2013-2014 Californian drought. We evaluate whether the observed increase in near-surface air temperature should be considered a forcing (as per standard meteorological approaches) or a feedback (as per standard agricultural and hydrologic approaches). We find that the radiative perturbation associated with the drought has a distinct radiative signature for more incoming shortwave- and less incoming longwave-radiation. That result, coupled with estimates of decreased evapotranspiration show that around two-third of the warming has a radiative origin and the remaining one-third is the result of a surface feedback from reduced evaporative cooling. Hence, the radiative perturbation during the recent Californian drought was distinctly different from the projected radiative perturbation of the enhanced greenhouse effect. We conclude that the warming experienced during meteorological drought is very different from the warming projected as a consequence of the enhanced greenhouse effect.

  4. Trophic mismatch requires seasonal heterogeneity of warming.

    PubMed

    Straile, Dietmar; Kerimoglu, Onur; Peeters, Frank

    2015-10-01

    Climate warming has been shown to advance the phenology of species. Asynchronous changes in phenology between interacting species may disrupt feeding interactions (phenological mismatch), which could have tremendous consequences for ecosystem functioning. Long-term field observations have suggested asynchronous shifts in phenology with warming, whereas experimental studies have not been conclusive. Using proxy-based modeling of three trophic levels (algae, herbivores, and fish), we .show that asynchronous changes in phenology only occur if warming is seasonally heterogeneous, but not if warming is constant throughout the year. If warming is seasonally heterogeneous, the degree and even direction of asynchrony depends on the specific seasonality of the warming. Conclusions about phenological mismatches in food web interactions may therefore produce controversial results if the analyses do not distinguish between seasonally constant and seasonal specific warming. Furthermore, our results suggest that predicting asynchrony between interacting species requires reliable warming predictions that resolve sub-seasonal time scales.

  5. Documentation for the Waste Reduction Model (WARM)

    EPA Pesticide Factsheets

    This page describes the WARM documentation files and provides links to all documentation files associated with EPA’s Waste Reduction Model (WARM). The page includes a brief summary of the chapters documenting the greenhouse gas emission and energy factors.

  6. Global warming: Clouds cooled the Earth

    NASA Astrophysics Data System (ADS)

    Mauritsen, Thorsten

    2016-12-01

    The slow instrumental-record warming is consistent with lower-end climate sensitivity. Simulations and observations now show that changing sea surface temperature patterns could have affected cloudiness and thereby dampened the warming.

  7. Versions of the Waste Reduction Model (WARM)

    EPA Pesticide Factsheets

    This page provides a brief chronology of changes made to EPA’s Waste Reduction Model (WARM), organized by WARM version number. The page includes brief summaries of changes and updates since the previous version.

  8. Waste Reduction Model (WARM) Resources for Students

    EPA Pesticide Factsheets

    This page provides a brief overview of how EPA’s Waste Reduction Model (WARM) can be used by students. The page includes a brief summary of uses of WARM for the audience and links to other resources.

  9. Warming trends: Adapting to nonlinear change

    SciTech Connect

    Jonko, Alexandra K.

    2015-01-28

    As atmospheric carbon dioxide concentrations rise, some regions are expected to warm more than others. Research suggests that whether warming will intensify or slow down over time also depends on location.

  10. Arctic climate change: Greenhouse warming unleashed

    NASA Astrophysics Data System (ADS)

    Mauritsen, Thorsten

    2016-04-01

    Human activity alters the atmospheric composition, which leads to global warming. Model simulations suggest that reductions in emission of sulfur dioxide from Europe since the 1970s could have unveiled rapid Arctic greenhouse gas warming.

  11. Lagrangian description of warm plasmas

    NASA Technical Reports Server (NTRS)

    Kim, H.

    1970-01-01

    Efforts are described to extend the averaged Lagrangian method of describing small signal wave propagation and nonlinear wave interaction, developed by earlier workers for cold plasmas, to the more general conditions of warm collisionless plasmas, and to demonstrate particularly the effectiveness of the method in analyzing wave-wave interactions. The theory is developed for both the microscopic description and the hydrodynamic approximation to plasma behavior. First, a microscopic Lagrangian is formulated rigorously, and expanded in terms of perturbations about equilibrium. Two methods are then described for deriving a hydrodynamic Lagrangian. In the first of these, the Lagrangian is obtained by velocity integration of the exact microscopic Lagrangian. In the second, the expanded hydrodynamic Lagrangian is obtained directly from the expanded microscopic Lagrangian. As applications of the microscopic Lagrangian, the small-signal dispersion relations and the coupled mode equations are derived for all possible waves in a warm infinite, weakly inhomogeneous magnetoplasma, and their interactions are examined.

  12. Hydrological consequences of global warming

    SciTech Connect

    Miller, Norman L.

    2009-06-01

    The 2007 Intergovernmental Panel for Climate Change indicates there is strong evidence that the atmospheric concentration of carbon dioxide far exceeds the natural range over the last 650,000 years, and this recent warming of the climate system is unequivocal, resulting in more frequent extreme precipitation events, earlier snowmelt runoff, increased winter flood likelihoods, increased and widespread melting of snow and ice, longer and more widespread droughts, and rising sea level. The effects of recent warming has been well documented and climate model projections indicate a range of hydrological impacts with likely to very likely probabilities (67 to 99 percent) of occurring with significant to severe consequences in response to a warmer lower atmosphere with an accelerating hydrologic cycle.

  13. Multidecadal warming of Antarctic waters.

    PubMed

    Schmidtko, Sunke; Heywood, Karen J; Thompson, Andrew F; Aoki, Shigeru

    2014-12-05

    Decadal trends in the properties of seawater adjacent to Antarctica are poorly known, and the mechanisms responsible for such changes are uncertain. Antarctic ice sheet mass loss is largely driven by ice shelf basal melt, which is influenced by ocean-ice interactions and has been correlated with Antarctic Continental Shelf Bottom Water (ASBW) temperature. We document the spatial distribution of long-term large-scale trends in temperature, salinity, and core depth over the Antarctic continental shelf and slope. Warming at the seabed in the Bellingshausen and Amundsen seas is linked to increased heat content and to a shoaling of the mid-depth temperature maximum over the continental slope, allowing warmer, saltier water greater access to the shelf in recent years. Regions of ASBW warming are those exhibiting increased ice shelf melt. Copyright © 2014, American Association for the Advancement of Science.

  14. MCCB warm adjustment testing concept

    NASA Astrophysics Data System (ADS)

    Erdei, Z.; Horgos, M.; Grib, A.; Preradović, D. M.; Rodic, V.

    2016-08-01

    This paper presents an experimental investigation in to operating of thermal protection device behavior from an MCCB (Molded Case Circuit Breaker). One of the main functions of the circuit breaker is to assure protection for the circuits where mounted in for possible overloads of the circuit. The tripping mechanism for the overload protection is based on a bimetal movement during a specific time frame. This movement needs to be controlled and as a solution to control this movement we choose the warm adjustment concept. This concept is meant to improve process capability control and final output. The warm adjustment device design will create a unique adjustment of the bimetal position for each individual breaker, determined when the testing current will flow thru a phase which needs to trip in a certain amount of time. This time is predetermined due to scientific calculation for all standard types of amperages and complies with the IEC 60497 standard requirements.

  15. Analysis of data from spacecraft (stratospheric warmings)

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The details of the stratospheric warming processes as to time, area, and intensity were established, and the warmings with other terrestrial and solar phenomena occurring at satellite platform altitudes, or observable from satellite platforms, were correlated. Links were sought between the perturbed upper atmosphere (mesosphere and thermosphere) and the stratosphere that might explain stratospheric warmings.

  16. Economic Theory and Global Warming

    NASA Astrophysics Data System (ADS)

    Uzawa, Hirofumi

    2003-08-01

    Hirofumi Uzawa's theoretical framework addresses three major problems concerning global warming and other environmental hazards. First, it considers all phenomena involved with global environmental issues that exhibit externalities of one kind or another. Secondly, it covers global environmental issues involving international and intergenerational equity and justice. Lastly, it deals with global environmental issues concerning the management of the atmosphere, the oceans, water, soil, and other natural resources having to be decided by a consensus of affected countries.

  17. The heated debate. [Global warming

    SciTech Connect

    Balling, R.C. Jr.

    1992-01-01

    The Heated Debate challenges head on the popular vision' of anthropogenically-caused global warming as characterized by catastrophic sea level rise, drought-desiccated farmlands, and more frequent and intense hurricanes spinning up and out from warmer tropical seas. The message of this book is that apocalyptic devastation of natural ecosystems and human socio-economic systems will not necessarily follow from a mild warming of earth's climate. According to Balling, the specter of apocalypse is clearly the dominant view held by scientists, decisionmakers and the public specter of apocalypse is clearly the dominant view held by scientists, decisionmakers and the public at large, and, in his view, it is just as clearly incorrect based on a careful examination of the historical evidence. The Heated Debate present the other side' of global warming; a kinder, gentler greenhouse debate, the stated purpose of the book is to provide the reader with some background to the greenhouse issue, present an analysis of the certainties and uncertainties for future climate change, and examine the most probably changes in climate that may occur as the greenhouse gases increase in concentration. Ultimately the author hopes the book will more completely inform decisionmakers so that they do not commit money and resources to what may turn out to be a non-problem. Indeed, global warming may have many more benefits than costs, and, in any event, the (climate) penalty for postponing action a few years is potentially small, while our knowledge base will increase tremendously allowing society to make wiser and more informed decisions.

  18. The Discovery of Global Warming

    NASA Astrophysics Data System (ADS)

    MacCracken, Michael C.

    2004-07-01

    At the beginning of the twentieth century, the prospect of ``global warming'' as a result of human activities was thought to be far off, and in any case, likely to be beneficial. As we begin the twenty-first century, science adviser to the British government, Sir David King, has said that he considers global warming to be the world's most important problem, including terrorism. Yet, dealing with it has become the subject of a contentious international protocol, numerous conferences of international diplomats, and major scientific assessments and research programs. Spencer Weart, who is director of the Center for History of Physics of the American Institute of Physics, has taken on the challenge of explaining how this came to be. In the tradition of the Intergovernmental Panel on Climate Change (IPCC), which was established in 1988 to evaluate and assess the state of global warming science, this book is roughly equivalent to the Technical Summary, in terms of its technical level, being quite readable, but with substantive content about the main lines of evidence. Underpinning this relatively concise presentation, there is a well-developed-and still developing-Web site that, like the detailed chapters of the full IPCC assessment reports, provides vastly more information and linkages to a much wider set of reference materials (see http://www.aip.org/history/climate).

  19. The threat of global warming

    SciTech Connect

    1995-12-15

    If the scientific predictions of global warming hold true, there`s trouble ahead for much of the world`s fresh water - and for people living in low-lying areas. The phenomenon, first described in the 1980`s, attributes projected rises in global temperatures to the emission of carbon dioxide and other {open_quotes}greenhouse gases,{close_quotes} so called because they trap the sun`s solar energy close to the Earth`s surface, much as a glass roof helps keep a greenhouse warm. The overwhelming source of these emission is the burning of fossil fuels such as oil, gasoline, coal and natural gas, the principal power sources of modern industry and transportation. In 1988, the United Nations set up the Intergovernmental Panel on Climate Change (IPCC) to study the validity and potential effects of global warming. The panel, composed of an international group of climate scientists, issued a report in June 1990 predicting a nearly two-degree rise in the globe`s average temperature by 2020. At that unprecedented rate of increase, the panel found, humankind would be living in a hotter environment that ever before.

  20. Global warming: Economic policy responses

    SciTech Connect

    Dornbusch, R.; Poterba, J.M.

    1991-01-01

    This volume contains the proceedings of a conference that brought together economic experts from Europe, the US, Latin America, and Japan to evaluate key issues in the policy debate in global warming. The following issues are at the center of debates on alternative policies to address global warming: scientific evidence on the magnitude of global warming and the extent to which it is due to human activities; availability of economic tools to control the anthropogenic emissions of greenhouse gases, and how vigorously should they be applied; and political economy considerations which influence the design of an international program for controlling greenhouse gases. Many perspectives are offered on the approaches to remedying environmental problems that are currently being pursued in Europe and the Pacific Rim. Deforestation in the Amazon is discussed, as well as ways to slow it. Public finance assessments are presented of both the domestic and international policy issues raised by plans to levy a tax on the carbon emissions from various fossil fuels. Nine chapters have been processed separately for inclusion in the appropriate data bases.

  1. Warm Dense Matter: An Overview

    SciTech Connect

    Kalantar, D H; Lee, R W; Molitoris, J D

    2004-04-21

    This document provides a summary of the ''LLNL Workshop on Extreme States of Materials: Warm Dense Matter to NIF'' which was held on 20, 21, and 22 February 2002 at the Wente Conference Center in Livermore, CA. The warm dense matter regime, the transitional phase space region between cold material and hot plasma, is presently poorly understood. The drive to understand the nature of matter in this regime is sparking scientific activity worldwide. In addition to pure scientific interest, finite temperature dense matter occurs in the regimes of interest to the SSMP (Stockpile Stewardship Materials Program). So that obtaining a better understanding of WDM is important to performing effective experiments at, e.g., NIF, a primary mission of LLNL. At this workshop we examined current experimental and theoretical work performed at, and in conjunction with, LLNL to focus future activities and define our role in this rapidly emerging research area. On the experimental front LLNL plays a leading role in three of the five relevant areas and has the opportunity to become a major player in the other two. Discussion at the workshop indicated that the path forward for the experimental efforts at LLNL were two fold: First, we are doing reasonable baseline work at SPLs, HE, and High Energy Lasers with more effort encouraged. Second, we need to plan effectively for the next evolution in large scale facilities, both laser (NIF) and Light/Beam sources (LCLS/TESLA and GSI) Theoretically, LLNL has major research advantages in areas as diverse as the thermochemical approach to warm dense matter equations of state to first principles molecular dynamics simulations. However, it was clear that there is much work to be done theoretically to understand warm dense matter. Further, there is a need for a close collaboration between the generation of verifiable experimental data that can provide benchmarks of both the experimental techniques and the theoretical capabilities. The conclusion of this

  2. Global warming and obesity: a systematic review.

    PubMed

    An, R; Ji, M; Zhang, S

    2017-10-04

    Global warming and the obesity epidemic are two unprecedented challenges mankind faces today. A literature search was conducted in the PubMed, Web of Science, EBSCO and Scopus for articles published until July 2017 that reported findings on the relationship between global warming and the obesity epidemic. Fifty studies were identified. Topic-wise, articles were classified into four relationships - global warming and the obesity epidemic are correlated because of common drivers (n = 21); global warming influences the obesity epidemic (n = 13); the obesity epidemic influences global warming (n = 13); and global warming and the obesity epidemic influence each other (n = 3). We constructed a conceptual model linking global warming and the obesity epidemic - the fossil fuel economy, population growth and industrialization impact land use and urbanization, motorized transportation and agricultural productivity and consequently influences global warming by excess greenhouse gas emission and the obesity epidemic by nutrition transition and physical inactivity; global warming also directly impacts obesity by food supply/price shock and adaptive thermogenesis, and the obesity epidemic impacts global warming by the elevated energy consumption. Policies that endorse deployment of clean and sustainable energy sources, and urban designs that promote active lifestyles, are likely to alleviate the societal burden of global warming and obesity. © 2017 World Obesity Federation.

  3. Methods of Patient Warming during Abdominal Surgery

    PubMed Central

    Shao, Li; Zheng, Hong; Jia, Feng-Ju; Wang, Hui-Qin; Liu, Li; Sun, Qi; An, Meng-Ying; Zhang, Xiu-Hua; Wen, Hao

    2012-01-01

    Background Keeping abdominal surgery patients warm is common and warming methods are needed in power outages during natural disasters. We aimed to evaluate the efficacy of low-cost, low-power warming methods for maintaining normothermia in abdominal surgery patients. Methods Patients (n = 160) scheduled for elective abdominal surgery were included in this prospective clinical study. Five warming methods were applied: heated blood transfusion/fluid infusion vs. unheated; wrapping patients vs. not wrapping; applying moist dressings, heated or not; surgical field rinse heated or not; and applying heating blankets or not. Patients’ nasopharyngeal and rectal temperatures were recorded to evaluate warming efficacy. Significant differences were found in mean temperatures of warmed patients compared to those not warmed. Results When we compared temperatures of abdominal surgery patient groups receiving three specific warming methods with temperatures of control groups not receiving these methods, significant differences were revealed in temperatures maintained during the surgeries between the warmed groups and controls. Discussion The value of maintaining normothermia in patients undergoing abdominal surgery under general anesthesia is accepted. Three effective economical and practically applicable warming methods are combined body wrapping and heating blanket; combined body wrapping, heated moist dressings, and heating blanket; combined body wrapping, heated moist dressings, and warmed surgical rinse fluid, with or without heating blanket. These methods are practically applicable when low-cost method is indeed needed. PMID:22808045

  4. Methods of patient warming during abdominal surgery.

    PubMed

    Shao, Li; Zheng, Hong; Jia, Feng-Ju; Wang, Hui-Qin; Liu, Li; Sun, Qi; An, Meng-Ying; Zhang, Xiu-Hua; Wen, Hao

    2012-01-01

    Keeping abdominal surgery patients warm is common and warming methods are needed in power outages during natural disasters. We aimed to evaluate the efficacy of low-cost, low-power warming methods for maintaining normothermia in abdominal surgery patients. Patients (n = 160) scheduled for elective abdominal surgery were included in this prospective clinical study. Five warming methods were applied: heated blood transfusion/fluid infusion vs. unheated; wrapping patients vs. not wrapping; applying moist dressings, heated or not; surgical field rinse heated or not; and applying heating blankets or not. Patients' nasopharyngeal and rectal temperatures were recorded to evaluate warming efficacy. Significant differences were found in mean temperatures of warmed patients compared to those not warmed. When we compared temperatures of abdominal surgery patient groups receiving three specific warming methods with temperatures of control groups not receiving these methods, significant differences were revealed in temperatures maintained during the surgeries between the warmed groups and controls. The value of maintaining normothermia in patients undergoing abdominal surgery under general anesthesia is accepted. Three effective economical and practically applicable warming methods are combined body wrapping and heating blanket; combined body wrapping, heated moist dressings, and heating blanket; combined body wrapping, heated moist dressings, and warmed surgical rinse fluid, with or without heating blanket. These methods are practically applicable when low-cost method is indeed needed.

  5. Warm/cold cloud processes

    NASA Technical Reports Server (NTRS)

    Bowdle, D. A.

    1979-01-01

    Technical assistance continued in support of the Atmospheric Cloud Physics Laboratory is discussed. A study of factors affecting warm cloud formation showed that the time of formation during an arbitrary expansion is independent of carrier gas composition for ideal gases and independent of aerosol concentration for low concentrations of very small aerosols. Equipment and procedures for gravimetric evaluation of a precision saturator were laboratory tested. A numerical feasibility study was conducted for the stable levitation of charged solution droplets by an electric field in a one-g static diffusion chamber. The concept, operating principles, applications, limits, and sensitivity of the levitation technique are discussed.

  6. [Medical consequences of global warming].

    PubMed

    Swynghedauw, Bernard

    2009-04-01

    The global warming of the planet and its anthropogenic origin are no longer debatable. Nevertheless, from a medical point of view, while the epidemiological consequences of the warming are rather well-known, the biological consequences are still poorly documented. This is a good example of evolutionary (or darwinian) medicine. The research strategy of this systematic review is based on both PubMed during the period of 2000-2007 and several reviews articles for the period >2000. From a medical point of view, there are four types of consequences. 1-The simple elevation of the average external temperature is accompanied by an increased global mortality and morbidity, the mortality/external temperature is a J curve, with the warm branch more pronounced than the cold one. A recent study on 50 different cities had confirmed that global, and more specifically cardiovascular mortalities were enhanced at the two extreme of the temperatures. 2-The acute heatwaves, such as that which happened in France in August 2003, have been studied in detail by several groups. The mortality which was observed during the recent heatwaves was not compensated by harvesting, strongly suggesting that we were dealing with heat stroke, and that such an increased mortality was more reflecting the limits of our adaptational capacities than aggravation of a previously altered health status. 3-Climate changes have modified the repartition and virulence of pathogenic agents (dengue, malaria...) and above all their vectors. Such modifications were exponential and are likely to reflect the biological properties of parasites. 4-Indirect consequences of global warming include variations in the hydraulic cycle, the new form of tropical hurricanes and many different changes affecting both biodiversity and ecosystems. They will likely result in an increased level of poverty. These finding gave rise to several basic biological questions, rarely evoked, and that concern the limits of the adaptational

  7. Global warming and biological diversity

    SciTech Connect

    Peters, R.L.; Lovejoy, T.E.

    1992-01-01

    This book is based on presentations given at the World Wildlife Fund's Conference on Consequences of the Greenhouse Effect for Biological Diverisity in 1988, and includes updated literature citations. The general topics covered in the book include the following: overview; summary of past responses of plants to climatic change; general ecological and physiological responses; ecosystems in 4 specific regions (arctic marine, Alaskan North Slope, NW US forests, and Mediterranean); global warming's implications for conservation. Ideas and data from many ecosystems and information about the relationships between biodiversity and climatic change are brought together with a balance of factual information and defensible scientific prognostication.

  8. Simulated sudden stratospheric warming - Synoptic evolution

    NASA Technical Reports Server (NTRS)

    Blackshear, W. T.; Grose, W. L.; Turner, R. E.

    1987-01-01

    An analysis is presented of a sudden stratospheric warming event which occurred spontaneously during a general circulation model simulation of the global atmospheric circulation. Two separate warming pulses exhibit the same dynamical evolution with a 'cycle' of about two weeks. Two distinct phases of the warming cycle are apparent: (1) the generation of an intense localized warm cell in conjunction with significant adiabatic heating associated with cross-isobar flow which has been induced by vertically propagating long wave disturbances; and (2) the northward transport of that warm cell via advection by the essentially geostrophic windfield corresponding to an intense, offset polar cyclone, in conjunction with a strong Aleutian anticyclone. During the first warming pulse in January, a moderate Aleutian anticyclone was in place prior to the warming cycle and was intensified by interaction with an eastward traveling anticyclone induced by the differential advection of the warm cell. The second warming pulse occurred in early February with a strong Aleutian anticyclone already established. In contrast to the January event, the warming in February culminated with reversal of the zonal westerlies to easterlies over a significant depth of the stratosphere.

  9. Simulated sudden stratospheric warming - Synoptic evolution

    NASA Technical Reports Server (NTRS)

    Blackshear, W. T.; Grose, W. L.; Turner, R. E.

    1987-01-01

    An analysis is presented of a sudden stratospheric warming event which occurred spontaneously during a general circulation model simulation of the global atmospheric circulation. Two separate warming pulses exhibit the same dynamical evolution with a 'cycle' of about two weeks. Two distinct phases of the warming cycle are apparent: (1) the generation of an intense localized warm cell in conjunction with significant adiabatic heating associated with cross-isobar flow which has been induced by vertically propagating long wave disturbances; and (2) the northward transport of that warm cell via advection by the essentially geostrophic windfield corresponding to an intense, offset polar cyclone, in conjunction with a strong Aleutian anticyclone. During the first warming pulse in January, a moderate Aleutian anticyclone was in place prior to the warming cycle and was intensified by interaction with an eastward traveling anticyclone induced by the differential advection of the warm cell. The second warming pulse occurred in early February with a strong Aleutian anticyclone already established. In contrast to the January event, the warming in February culminated with reversal of the zonal westerlies to easterlies over a significant depth of the stratosphere.

  10. Population growth and global warming.

    PubMed

    Short, R V

    2009-01-01

    When I was born in 1930, the human population of the world was a mere 2 billion. Today, it has already reached 6.8 billion, and is projected to reach 9.1 billion by 2050. That is unsustainable. It is slowly beginning to dawn on us that Global Warming is the result of increasing human CO2 emissions, and the more people there are in the world, the worse it will become. Ultimately, it is the sky that will prove to be the limit to our numbers. The developed countries of the world are the most affluent, and also the most effluent, so we must lead by example and contain our own population growth and per capita emissions. We also have a big debt to repay to former colonial territories in Africa, Asia and South America, who desperately need our help to contain their excessive rates of population growth. Belgian and Dutch obstetricians and gynaecologists can play a critical role in this endeavour. After all, we already have a pill that will stop global warming - the oral contraceptive pill.

  11. Population growth and global warming

    PubMed Central

    Short, R.V.

    2009-01-01

    When I was born in 1930, the human population of the world was a mere 2 billion. Today, it has already reached 6.8 billion, and is projected to reach 9.1 billion by 2050. That is unsustainable. It is slowly beginning to dawn on us that Global Warming is the result of increasing human CO2 emissions, and the more people there are in the world, the worse it will become. Ultimately, it is the sky that will prove to be the limit to our numbers. The developed countries of the world are the most affluent, and also the most effluent, so we must lead by example and contain our own population growth and per capita emissions. We also have a big debt to repay to former colonial territories in Africa, Asia and South America, who desperately need our help to contain their excessive rates of population growth. Belgian and Dutch obstetricians and gynaecologists can play a critical role in this endeavour. After all, we already have a pill that will stop global warming – the oral contraceptive pill. PMID:25478068

  12. Warm gas TVC design study

    NASA Technical Reports Server (NTRS)

    Moorhead, S. B., Jr.

    1973-01-01

    A warm gas thrust vector control system was studied to optimize the injection geometry for a specific engine configuration, and an injection valve was designed capable of meeting the base line requirements. To optimize injection geometry, studies were made to determine the performance effects of varying injection location, angle, port size, and port configuration. Having minimized the injection flow rate required, a warm gas valve was designed to handle the required flow. A direct drive hydraulic servovalve capable of operating with highly contaminated hydraulic fluid was designed. The valve is sized to flow 15 gpm at 3000 psia and the direct drive feature is capable of applying a spool force of 200 pounds. The baseline requirements are the development of 6 deg of thrust vector control utilizing 2000 F (total temperature) gas for 180 seconds on a 1.37 million pound thrust engine burning LOX and RP-1 at a chamber pressure of 250 psia with a 155 inch long conical nozzle having a 68 inch diameter throat and a 153 inch diameter exit.

  13. Forecasting phenology under global warming

    PubMed Central

    Ibáñez, Inés; Primack, Richard B.; Miller-Rushing, Abraham J.; Ellwood, Elizabeth; Higuchi, Hiroyoshi; Lee, Sang Don; Kobori, Hiromi; Silander, John A.

    2010-01-01

    As a consequence of warming temperatures around the world, spring and autumn phenologies have been shifting, with corresponding changes in the length of the growing season. Our understanding of the spatial and interspecific variation of these changes, however, is limited. Not all species are responding similarly, and there is significant spatial variation in responses even within species. This spatial and interspecific variation complicates efforts to predict phenological responses to ongoing climate change, but must be incorporated in order to build reliable forecasts. Here, we use a long-term dataset (1953–2005) of plant phenological events in spring (flowering and leaf out) and autumn (leaf colouring and leaf fall) throughout Japan and South Korea to build forecasts that account for these sources of variability. Specifically, we used hierarchical models to incorporate the spatial variability in phenological responses to temperature to then forecast species' overall and site-specific responses to global warming. We found that for most species, spring phenology is advancing and autumn phenology is getting later, with the timing of events changing more quickly in autumn compared with the spring. Temporal trends and phenological responses to temperature in East Asia contrasted with results from comparable studies in Europe, where spring events are changing more rapidly than are autumn events. Our results emphasize the need to study multiple species at many sites to understand and forecast regional changes in phenology. PMID:20819816

  14. A sudden stratospheric warming compendium

    NASA Astrophysics Data System (ADS)

    Butler, Amy H.; Sjoberg, Jeremiah P.; Seidel, Dian J.; Rosenlof, Karen H.

    2017-02-01

    Major, sudden midwinter stratospheric warmings (SSWs) are large and rapid temperature increases in the winter polar stratosphere are associated with a complete reversal of the climatological westerly winds (i.e., the polar vortex). These extreme events can have substantial impacts on winter surface climate, including increased frequency of cold air outbreaks over North America and Eurasia and anomalous warming over Greenland and eastern Canada. Here we present a SSW Compendium (SSWC), a new database that documents the evolution of the stratosphere, troposphere, and surface conditions 60 days prior to and after SSWs for the period 1958-2014. The SSWC comprises data from six different reanalysis products: MERRA2 (1980-2014), JRA-55 (1958-2014), ERA-interim (1979-2014), ERA-40 (1958-2002), NOAA20CRv2c (1958-2011), and NCEP-NCAR I (1958-2014). Global gridded daily anomaly fields, full fields, and derived products are provided for each SSW event. The compendium will allow users to examine the structure and evolution of individual SSWs, and the variability among events and among reanalysis products. The SSWC is archived and maintained by NOAA's National Centers for Environmental Information (NCEI, doi:10.7289/V5NS0RWP).

  15. Daytime warming has stronger negative effects on soil nematodes than night-time warming.

    PubMed

    Yan, Xiumin; Wang, Kehong; Song, Lihong; Wang, Xuefeng; Wu, Donghui

    2017-03-07

    Warming of the climate system is unequivocal, that is, stronger warming during night-time than during daytime. Here we focus on how soil nematodes respond to the current asymmetric warming. A field infrared heating experiment was performed in the western of the Songnen Plain, Northeast China. Three warming modes, i.e. daytime warming, night-time warming and diurnal warming, were taken to perform the asymmetric warming condition. Our results showed that the daytime and diurnal warming treatment significantly decreased soil nematodes density, and night-time warming treatment marginally affected the density. The response of bacterivorous nematode and fungivorous nematode to experimental warming showed the same trend with the total density. Redundancy analysis revealed an opposite effect of soil moisture and soil temperature, and the most important of soil moisture and temperature in night-time among the measured environment factors, affecting soil nematode community. Our findings suggested that daily minimum temperature and warming induced drying are most important factors affecting soil nematode community under the current global asymmetric warming.

  16. Daytime warming has stronger negative effects on soil nematodes than night-time warming.

    PubMed

    Yan, Xiumin; Wang, Kehong; Song, Lihong; Wang, Xuefeng; Wu, Donghui

    2017-03-20

    Warming of the climate system is unequivocal, that is, stronger warming during night-time than during daytime. Here we focus on how soil nematodes respond to the current asymmetric warming. A field infrared heating experiment was performed in the western of the Songnen Plain, Northeast China. Three warming modes, i.e. daytime warming, night-time warming and diurnal warming, were taken to perform the asymmetric warming condition. Our results showed that the daytime and diurnal warming treatment significantly decreased soil nematodes density, and night-time warming treatment marginally affected the density. The response of bacterivorous nematode and fungivorous nematode to experimental warming showed the same trend with the total density. Redundancy analysis revealed an opposite effect of soil moisture and soil temperature, and the most important of soil moisture and temperature in night-time among the measured environment factors, affecting soil nematode community. Our findings suggested that daily minimum temperature and warming induced drying are most important factors affecting soil nematode community under the current global asymmetric warming.

  17. Daytime warming has stronger negative effects on soil nematodes than night-time warming

    NASA Astrophysics Data System (ADS)

    Yan, Xiumin; Wang, Kehong; Song, Lihong; Wang, Xuefeng; Wu, Donghui

    2017-03-01

    Warming of the climate system is unequivocal, that is, stronger warming during night-time than during daytime. Here we focus on how soil nematodes respond to the current asymmetric warming. A field infrared heating experiment was performed in the western of the Songnen Plain, Northeast China. Three warming modes, i.e. daytime warming, night-time warming and diurnal warming, were taken to perform the asymmetric warming condition. Our results showed that the daytime and diurnal warming treatment significantly decreased soil nematodes density, and night-time warming treatment marginally affected the density. The response of bacterivorous nematode and fungivorous nematode to experimental warming showed the same trend with the total density. Redundancy analysis revealed an opposite effect of soil moisture and soil temperature, and the most important of soil moisture and temperature in night-time among the measured environment factors, affecting soil nematode community. Our findings suggested that daily minimum temperature and warming induced drying are most important factors affecting soil nematode community under the current global asymmetric warming.

  18. Daytime warming has stronger negative effects on soil nematodes than night-time warming

    PubMed Central

    Yan, Xiumin; Wang, Kehong; Song, Lihong; Wang, Xuefeng; Wu, Donghui

    2017-01-01

    Warming of the climate system is unequivocal, that is, stronger warming during night-time than during daytime. Here we focus on how soil nematodes respond to the current asymmetric warming. A field infrared heating experiment was performed in the western of the Songnen Plain, Northeast China. Three warming modes, i.e. daytime warming, night-time warming and diurnal warming, were taken to perform the asymmetric warming condition. Our results showed that the daytime and diurnal warming treatment significantly decreased soil nematodes density, and night-time warming treatment marginally affected the density. The response of bacterivorous nematode and fungivorous nematode to experimental warming showed the same trend with the total density. Redundancy analysis revealed an opposite effect of soil moisture and soil temperature, and the most important of soil moisture and temperature in night-time among the measured environment factors, affecting soil nematode community. Our findings suggested that daily minimum temperature and warming induced drying are most important factors affecting soil nematode community under the current global asymmetric warming. PMID:28317914

  19. Warm-Ring Structures in Intense Hurricanes

    NASA Astrophysics Data System (ADS)

    Espinosa, F. I.; Gonzalez, A. O.; Slocum, C. J.; Schubert, W. H.

    2014-12-01

    Typical hurricanes have a warm-core structure such that the warmest temperatures occur in the center of the hurricane. However, weather reconnaissance aircraft data has observed warm-rings in intense hurricanes. A warm-ring structure results when the warmest temperature anomalies occur on the outer edge of the eye. Schubert et al. (2007) suggests the Eliassen transverse circulation equation can model intense hurricanes with a warm-core structure in the upper troposphere and also a warm-ring structure in the lower. Although the thermal wind equation was used in the derivation of the transverse circulation equation, the thermal wind equation has not been used explicitly in an attempt to create such a temperature field. This study derives the thermal wind equation from the hydrostatic and the gradient wind equations to analyze the temperature, tangential velocity, and the absolute vorticity fields. Using observed hurricanes, a warm-ring structure is simulated with the thermal wind equation as the basis. With a prescribed temperature profile, the calculated tangential velocity and absolute vorticity fields resemble those of a realistic hurricane. Thus, the thermal wind equation can be used to create a realistic, intense hurricane with a warm ring structure. Schubert et al. (2007) discusses subsidence as a mechanism that leads to the warm-ring but the tangential velocity and absolute vorticity fields suggest some influence of boundary layer processes that should be explored in future research for a further understanding of warm-rings.

  20. Global warming; What needs to be done

    SciTech Connect

    Not Available

    1991-04-01

    This paper names global warming as a high-level risk. However, global warming's risk status is a point of debate in some circles, reflecting one of the complexities of using risk-based criteria to establish priorities for action. The position that global warming is a long-term environmental trend that must be halted. In this paper, argument son both sides of the global warming issue are presented to illustrate the difficulties associated with establishing the existence and magnitude of environmental and health risks, an issue that must be faced if the SAB recommendations for EPA policy change are implemented.

  1. DPIS for warm dense matter

    SciTech Connect

    Kondo, K.; Kanesue, T.; Horioka, K.; Okamura, M.

    2010-05-23

    Warm Dense Matter (WDM) offers an challenging problem because WDM, which is beyond ideal plasma, is in a low temperature and high density state with partially degenerate electrons and coupled ions. WDM is a common state of matter in astrophysical objects such as cores of giant planets and white dwarfs. The WDM studies require large energy deposition into a small target volume in a shorter time than the hydrodynamical time and need uniformity across the full thickness of the target. Since moderate energy ion beams ({approx} 0.3 MeV/u) can be useful tool for WDM physics, we propose WDM generation using Direct Plasma Injection Scheme (DPIS). In the DPIS, laser ion source is connected to the Radio Frequency Quadrupole (RFQ) linear accelerator directly without the beam transport line. DPIS with a realistic final focus and a linear accelerator can produce WDM.

  2. End Calorimeter Warm Tube Heater

    SciTech Connect

    Primdahl, K.; /Fermilab

    1991-08-06

    The Tevatron accelerator beam tube must pass through the End Calorimeter cryostats of the D-Zero Collider Detector. Furthermore, the End Calorimeter cryostats must be allowed to roll back forty inches without interruption of the vacuum system; hence, the Tev tube must slide through the End Calorimeter cryostat as it is rolled back. The Tev pass through the End Calorimeter can actually be thought of as a cluster of concentric tubes: Tev tube, warm (vacuum vessel) tube, IS layers of superinsulation, cold tube (argon vessel), and Inner Hadronic center support tube. M. Foley generated an ANSYS model to study the heat load. to the cryostat. during collider physics studies; that is, without operation of the heater. A sketch of the model is included in the appendix. The vacuum space and superinsulation was modeled as a thermal solid, with conductivity derived from tests performed at Fermilab. An additional estimate was done. by this author, using data supplied by NR-2. a superinsulation manufacturer. The ANSYS result and hand calculation are in close agreement. The ANSYS model was modified. by this author. to incorporate the effect of the heater. Whereas the earlier model studied steady state operation only. the revised model considers the heater-off steady state mode as the initial condition. then performs a transient analysis with a final load step for time tending towards infinity. Results show the thermal gradient as a function of time and applied voltage. It should be noted that M. Foley's model was generated for one half the warm tube. implying the tube to be symmetric. In reality. the downstream connection (relative to the collision point) attachment to the vacuum shell is via several convolutions of a 0.020-inch wall bellows; hence. a nearly adiabatic boundary condition. Accordingly. the results reported in the table reflect extrapolation of the curves to the downstream end of the tube. Using results from the ANSYS analysis, that is, tube temperature and

  3. Meteorology: hurricanes and global warming.

    PubMed

    Landsea, Christopher W

    2005-12-22

    Anthropogenic climate change has the potential for slightly increasing the intensity of tropical cyclones through warming of sea surface temperatures. Emanuel has shown a striking and surprising association between sea surface temperatures and destructiveness by tropical cyclones in the Atlantic and western North Pacific basins. However, I question his analysis on the following grounds: it does not properly represent the observations described; the use of his Atlantic bias-removal scheme may not be warranted; and further investigation of a substantially longer time series for tropical cyclones affecting the continental United States does not show a tendency for increasing destructiveness. These factors indicate that instead of "unprecedented" tropical cyclone activity having occurred in recent years, hurricane intensity was equal or even greater during the last active period in the mid-twentieth century.

  4. Warm gas in protoplanetary disks

    NASA Astrophysics Data System (ADS)

    van der Plas, Gerrit

    2010-12-01

    This thesis presents a study of warm CO, [OI] and H2 gas coming from the disks around Herbig Ae/Be stars. These various gas tracers are each a proxy for a different radial and vertical region of the PP disk surface. Our sample consists of disks whose shape (based on modeling of the the disk dust emission) can be divided into flaring and self-shadowed (flat). We find [1] evidence for the vertical decoupling of gas and dust in one disks (Chapter 2); [2] That disk geometry has a large influence on the spatial distribution and excitation mechanism of the CO emission (chapters 3,4); [3] Near-IR H 2 emission around 2 (out of 14) HAEBE stars, probably originating from large (±50AU) radii of the disk (chapter 5). In chapter 6 we investigate the trends between CO emission and disk geometry as noted in Chapter 3 and 4.

  5. Liquid Cooling/Warming Garment

    NASA Technical Reports Server (NTRS)

    Koscheyev, Victor S.; Leon, Gloria R.; Dancisak, Michael J.

    2010-01-01

    The NASA liquid cooling/ventilating garment (LCVG) currently in use was developed over 40 years ago. With the commencement of a greater number of extra-vehicular activity (EVA) procedures with the construction of the International Space Station, problems of astronaut comfort, as well as the reduction of the consumption of energy, became more salient. A shortened liquid cooling/warming garment (SLCWG) has been developed based on physiological principles comparing the efficacy of heat transfer of different body zones; the capability of blood to deliver heat; individual muscle and fat body composition as a basis for individual thermal profiles to customize the zonal sections of the garment; and the development of shunts to minimize or redirect the cooling/warming loop for different environmental conditions, physical activity levels, and emergency situations. The SLCWG has been designed and completed, based on extensive testing in rest, exercise, and antiorthostatic conditions. It is more energy efficient than the LCVG currently used by NASA. The total length of tubing in the SLCWG is approximately 35 percent less and the weight decreased by 20 percent compared to the LCVG. The novel features of the innovation are: 1. The efficiency of the SLCWG to maintain thermal status under extreme changes in body surface temperatures while using significantly less tubing than the LCVG. 2. The construction of the garment based on physiological principles of heat transfer. 3. The identification of the body areas that are most efficient in heat transfer. 4. The inclusion of a hood as part of the garment. 5. The lesser consumption of energy.

  6. Design and performance of combined infrared canopy and belowground warming in the B4WarmED (Boreal Forest Warming at an Ecotone in Danger) experiment.

    PubMed

    Rich, Roy L; Stefanski, Artur; Montgomery, Rebecca A; Hobbie, Sarah E; Kimball, Bruce A; Reich, Peter B

    2015-06-01

    Conducting manipulative climate change experiments in complex vegetation is challenging, given considerable temporal and spatial heterogeneity. One specific challenge involves warming of both plants and soils to depth. We describe the design and performance of an open-air warming experiment called Boreal Forest Warming at an Ecotone in Danger (B4WarmED) that addresses the potential for projected climate warming to alter tree function, species composition, and ecosystem processes at the boreal-temperate ecotone. The experiment includes two forested sites in northern Minnesota, USA, with plots in both open (recently clear-cut) and closed canopy habitats, where seedlings of 11 tree species were planted into native ground vegetation. Treatments include three target levels of plant canopy and soil warming (ambient, +1.7°C, +3.4°C). Warming was achieved by independent feedback control of voltage input to aboveground infrared heaters and belowground buried resistance heating cables in each of 72-7.0 m(2) plots. The treatments emulated patterns of observed diurnal, seasonal, and annual temperatures but with superimposed warming. For the 2009 to 2011 field seasons, we achieved temperature elevations near our targets with growing season overall mean differences (∆Tbelow ) of +1.84°C and +3.66°C at 10 cm soil depth and (∆T(above) ) of +1.82°C and +3.45°C for the plant canopies. We also achieved measured soil warming to at least 1 m depth. Aboveground treatment stability and control were better during nighttime than daytime and in closed vs. open canopy sites in part due to calmer conditions. Heating efficacy in open canopy areas was reduced with increasing canopy complexity and size. Results of this study suggest the warming approach is scalable: it should work well in small-statured vegetation such as grasslands, desert, agricultural crops, and tree saplings (<5 m tall).

  7. Efficient Warm-ups: Creating a Warm-up That Works.

    ERIC Educational Resources Information Center

    Lauffenburger, Sandra Kay

    1992-01-01

    Proper warm-up is important for any activity, but designing an effective warm-up can be time consuming. An alternative approach is to take a cue from Laban Movement Analysis (LMA) and consider movement design from the perspective of space and planes of motion. Efficient warm-up exercises using LMA are described. (SM)

  8. Warming: mechanism and latitude dependence

    NASA Astrophysics Data System (ADS)

    Barkin, Yury

    2010-05-01

    Introduction. In the work it is shown, that in present warming of climate of the Earth and in style of its display a fundamental role the mechanism of the forced swing and relative oscillations of eccentric core of the Earth and its mantle plays. Relative displacements of the centers of mass of the core and the mantle are dictated by the features of orbital motions of bodies of solar system and nonineriality of the Earth reference frame (or ot the mantle) at the motion of the Earth with respect to a baricenter of solar system and at rotation of the planet. As a result in relative translational displacements of the core and the mantle the frequencies characteristic for orbital motion of all bodies of solar system, and also their combination are shown. Methods of a space geodesy, gravimetry, geophysics, etc. unequivocally and clearly confirm phenomenon of drift of the center of mass of the Earth in define northern direction. This drift is characterized by the significant velocity in about 5 mm/yr. The unique opportunity of its explanation consists in the natural assumption of existence of the unidirectional relative displacement (drift) the center of mass of the core and the center of mass of the mantle of the Earth. And this displacement (at superfluous mass of the core in 16.7 % from the mass of full the Earth) is characterized still more significant velocity in 2.6 cm/yr and occurs on our geodynamic studies in a direction to Taimyr peninsula. The dynamic explanation to century drift for today does not exist. It is possible to note, however, that data of observations of last years, indirectly testifying that similar drifts of the centers of mass in present epoch occur on other bodies of Solar system have been obtain: the Sun, Mars, the Titan, Enceladus, the Neptune, etc. We connect with mentioned phenomena the observed secular variations of natural processes on this celestial bodies. I.e. it is possible to assume, that observable eccentric positions of the centers

  9. Global Warming: Lessons from Ozone Depletion

    ERIC Educational Resources Information Center

    Hobson, Art

    2010-01-01

    My teaching and textbook have always covered many physics-related social issues, including stratospheric ozone depletion and global warming. The ozone saga is an inspiring good-news story that's instructive for solving the similar but bigger problem of global warming. Thus, as soon as students in my physics literacy course at the University of…

  10. Greenhouse warming and the tropical water budget

    NASA Technical Reports Server (NTRS)

    Betts, Alan K.

    1990-01-01

    The present work takes issue with some of the theses of Lindzen's (1990) work on global warming, arguing in particular that Lindzen's work is hampered by the use of oversimplified models. Lindzen then presents a detailed reply to these arguments, emphasizing the fundamental importance of the upper tropospheric water-vapor budget to the question of global warming.

  11. Global Warming: How Much and Why?

    ERIC Educational Resources Information Center

    Lanouette, William

    1990-01-01

    Summarizes the history of the study of global warming and includes a discussion of the role of gases, like carbon dioxide, methane, and chlorofluorocarbon (CFC). Discusses modern research on the global warming, including computer modelling and the super-greenhouse effect. (YP)

  12. Cryosphere: Warming ocean erodes ice sheets

    NASA Astrophysics Data System (ADS)

    Kusahara, Kazuya

    2016-01-01

    Antarctic ice sheets are a key player in sea-level rise in a warming climate. Now an ice-sheet modelling study clearly demonstrates that an Antarctic ice sheet/shelf system in the Atlantic Ocean will be regulated by the warming of the surrounding Southern Ocean, not by marine-ice-sheet instability.

  13. Global Warming: Lessons from Ozone Depletion

    ERIC Educational Resources Information Center

    Hobson, Art

    2010-01-01

    My teaching and textbook have always covered many physics-related social issues, including stratospheric ozone depletion and global warming. The ozone saga is an inspiring good-news story that's instructive for solving the similar but bigger problem of global warming. Thus, as soon as students in my physics literacy course at the University of…

  14. Turkish Students' Ideas about Global Warming

    ERIC Educational Resources Information Center

    Kilinc, Ahmet; Stanisstreet, Martin; Boyes, Edward

    2008-01-01

    A questionnaire was used to explore the prevalence of ideas about global warming in Year 10 (age 15-16 years) school students in Turkey. The frequencies of individual scientific ideas and misconceptions about the causes, consequences and "cures" of global warming were identified. In addition, several general findings emerged from this…

  15. Exploring the Sociopolitical Dimensions of Global Warming

    ERIC Educational Resources Information Center

    Sadler, Troy D.; Klosterman, Michelle L.

    2009-01-01

    The authors present an activity to help high school students conceptualize the sociopolitical complexity of global warming through an exploration of varied perspectives on the issue. They argue that socioscientific issues such as global warming present important contexts for learning science and that the social and political dimensions of these…

  16. Exploring the Sociopolitical Dimensions of Global Warming

    ERIC Educational Resources Information Center

    Sadler, Troy D.; Klosterman, Michelle L.

    2009-01-01

    The authors present an activity to help high school students conceptualize the sociopolitical complexity of global warming through an exploration of varied perspectives on the issue. They argue that socioscientific issues such as global warming present important contexts for learning science and that the social and political dimensions of these…

  17. Warming of Water in a Glass

    ERIC Educational Resources Information Center

    Paulins, Paulis; Krauze, Armands; Ozolinsh, Maris; Muiznieks, Andris

    2016-01-01

    The article focuses on the process of water warming from 0 °C in a glass. An experiment is performed that analyzes the temperature in the top and bottom layers of water during warming. The experimental equipment is very simple and can be easily set up using devices available in schools. The temperature curves obtained from the experiment help us…

  18. Warming of Water in a Glass

    ERIC Educational Resources Information Center

    Paulins, Paulis; Krauze, Armands; Ozolinsh, Maris; Muiznieks, Andris

    2016-01-01

    The article focuses on the process of water warming from 0 °C in a glass. An experiment is performed that analyzes the temperature in the top and bottom layers of water during warming. The experimental equipment is very simple and can be easily set up using devices available in schools. The temperature curves obtained from the experiment help us…

  19. Global Warming: How Much and Why?

    ERIC Educational Resources Information Center

    Lanouette, William

    1990-01-01

    Summarizes the history of the study of global warming and includes a discussion of the role of gases, like carbon dioxide, methane, and chlorofluorocarbon (CFC). Discusses modern research on the global warming, including computer modelling and the super-greenhouse effect. (YP)

  20. Global Warming: Understanding and Teaching the Forecast.

    ERIC Educational Resources Information Center

    Andrews, Bill

    1995-01-01

    A resource for teaching about the consequences of global warming. Discusses feedback from the temperature increase, changes in the global precipitation pattern, effects on agriculture, weather extremes, effects on forests, effects on biodiversity, effects on sea levels, and actions which will help the global community cope with global warming. (LZ)

  1. Greenhouse warming and the tropical water budget

    NASA Technical Reports Server (NTRS)

    Betts, Alan K.

    1990-01-01

    The present work takes issue with some of the theses of Lindzen's (1990) work on global warming, arguing in particular that Lindzen's work is hampered by the use of oversimplified models. Lindzen then presents a detailed reply to these arguments, emphasizing the fundamental importance of the upper tropospheric water-vapor budget to the question of global warming.

  2. Warm-up: A Psychophysiological Phenomenon.

    ERIC Educational Resources Information Center

    Lopez, Richard; Dausman, Cindy

    1981-01-01

    The effectiveness of warm-up as an aid to athletic performance is related to an interaction of both psychological and physiological factors. Benefits of warm-up include an increase in blood and muscle temperatures and an increased muscular endurance. (JN)

  3. Global Warming: Understanding and Teaching the Forecast.

    ERIC Educational Resources Information Center

    Andrews, Bill

    1994-01-01

    A resource for the teaching of the history and causes of climate change. Discusses evidence of climate change from the Viking era, early ice ages, the most recent ice age, natural causes of climate change, human-made causes of climate change, projections of global warming, and unequal warming. (LZ)

  4. Global Warming: Understanding and Teaching the Forecast.

    ERIC Educational Resources Information Center

    Andrews, Bill

    1995-01-01

    A resource for teaching about the consequences of global warming. Discusses feedback from the temperature increase, changes in the global precipitation pattern, effects on agriculture, weather extremes, effects on forests, effects on biodiversity, effects on sea levels, and actions which will help the global community cope with global warming. (LZ)

  5. Global Warming: Understanding and Teaching the Forecast.

    ERIC Educational Resources Information Center

    Andrews, Bill

    1994-01-01

    A resource for the teaching of the history and causes of climate change. Discusses evidence of climate change from the Viking era, early ice ages, the most recent ice age, natural causes of climate change, human-made causes of climate change, projections of global warming, and unequal warming. (LZ)

  6. Global warming, insurance losses and financial industry

    SciTech Connect

    Low, N.C.

    1996-12-31

    Global warming causes extremely bad weather in the near term. They have already caught the attention of the insurance industry, as they suffered massive losses in the last decade. Twenty-one out of the 25 largest catastrophes in the US, mainly in the form of hurricanes have occurred in the last decade. The insurance industry has reacted by taking the risk of global warming in decisions as to pricing and underwriting decisions. But they have yet to take a more active role in regulating the factors that contributes to global warming. How global warming can impact the financial industry and the modern economy is explored. Insurance and modern financial derivatives are key to the efficient functioning of the modern economy, without which the global economy can still function but will take a giant step backward. Any risk as global warming that causes economic surprises will hamper the efficient working of the financial market and the modern economy.

  7. Urban warming reduces aboveground carbon storage

    PubMed Central

    Youngsteadt, Elsa; Dunn, Robert R.; Frank, Steven D.

    2016-01-01

    A substantial amount of global carbon is stored in mature trees. However, no experiments to date test how warming affects mature tree carbon storage. Using a unique, citywide, factorial experiment, we investigated how warming and insect herbivory affected physiological function and carbon sequestration (carbon stored per year) of mature trees. Urban warming increased herbivorous arthropod abundance on trees, but these herbivores had negligible effects on tree carbon sequestration. Instead, urban warming was associated with an estimated 12% loss of carbon sequestration, in part because photosynthesis was reduced at hotter sites. Ecosystem service assessments that do not consider urban conditions may overestimate urban tree carbon storage. Because urban and global warming are becoming more intense, our results suggest that urban trees will sequester even less carbon in the future. PMID:27708149

  8. Global Warming: Lessons from Ozone Depletion

    NASA Astrophysics Data System (ADS)

    Hobson, Art

    2010-11-01

    My teaching and textbook have always covered many physics-related social issues, including stratospheric ozone depletion and global warming. The ozone saga is an inspiring good-news story that's instructive for solving the similar but bigger problem of global warming. Thus, as soon as students in my physics literacy course at the University of Arkansas have developed a conceptual understanding of energy and of electromagnetism, including the electromagnetic spectrum, I devote a lecture (and a textbook section) to ozone depletion and another lecture (and section) to global warming. Humankind came together in 1986 and quickly solved, to the extent that humans can solve it, ozone depletion. We could do the same with global warming, but we haven't and as yet there's no sign that we will. The parallel between the ozone and global warming cases, and the difference in outcomes, are striking and instructive.

  9. Urban warming reduces aboveground carbon storage.

    PubMed

    Meineke, Emily; Youngsteadt, Elsa; Dunn, Robert R; Frank, Steven D

    2016-10-12

    A substantial amount of global carbon is stored in mature trees. However, no experiments to date test how warming affects mature tree carbon storage. Using a unique, citywide, factorial experiment, we investigated how warming and insect herbivory affected physiological function and carbon sequestration (carbon stored per year) of mature trees. Urban warming increased herbivorous arthropod abundance on trees, but these herbivores had negligible effects on tree carbon sequestration. Instead, urban warming was associated with an estimated 12% loss of carbon sequestration, in part because photosynthesis was reduced at hotter sites. Ecosystem service assessments that do not consider urban conditions may overestimate urban tree carbon storage. Because urban and global warming are becoming more intense, our results suggest that urban trees will sequester even less carbon in the future.

  10. Warm Disks from Giant Impacts

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2015-10-01

    In the process of searching for exoplanetary systems, weve discovered tens of debris disks close around distant stars that are especially bright in infrared wavelengths. New research suggests that we might be looking at the late stages of terrestrial planet formation in these systems.Forming Terrestrial PlanetsAccording to the widely-accepted formation model for our solar-system, protoplanets the size of Mars formed within a protoplanetary disk around our Sun. Eventually, the depletion of the gas in the disk led the orbits of these protoplanets to become chaotically unstable. Finally, in the giant impact stage, many of the protoplanets collided with each other ultimately leading to the formation of the terrestrial planets and their moons as we know them today.If giant impact stages occur in exoplanetary systems, too leading to the formation of terrestrial exoplanets how would we detect this process? According to a study led by Hidenori Genda of the Tokyo Institute of Technology, we might be already be witnessing this stage in observations of warm debris disks around other stars. To test this, Genda and collaborators model giant impact stages and determine what we would expect to see from a system undergoing this violent evolution.Modeling CollisionsSnapshots of a giant impact in one of the authors simulations. The collision causes roughly 0.05 Earth masses of protoplanetary material to be ejected from the system. Click for a closer look! [Genda et al. 2015]The collaborators run a series of simulations evolving protoplanetary bodies in a solar system. The simulations begin 10 Myr into the lifetime of the solar system, i.e., after the gas from the protoplanetary disk has had time to be cleared and the protoplanetary orbits begin to destabilize. The simulations end when the protoplanets are done smashing into each other and have again settled into stable orbits, typically after ~100 Myr.The authors find that, over an average giant impact stage, the total amount of

  11. Predator contributions to belowground responses to warming

    DOE PAGES

    Maran, A. M.; Pelini, S. L.

    2016-09-26

    Identifying the factors that control soil CO2 emissions will improve our ability to predict the magnitude of climate change–soil ecosystem feedbacks. Despite the integral role of invertebrates in belowground systems, they are excluded from climate change models. Soil invertebrates have consumptive and nonconsumptive effects on microbes, whose respiration accounts for nearly half of soil CO2 emissions. By altering the behavior and abundance of invertebrates that interact with microbes, invertebrate predators may have indirect effects on soil respiration. We examined the effects of a generalist arthropod predator on belowground respiration under different warming scenarios. Based on research suggesting invertebrates may mediatemore » soil CO2 emission responses to warming, we predicted that predator presence would result in increased emissions by negatively affecting these invertebrates. We altered the presence of wolf spiders (Pardosa spp.) in mesocosms containing a forest floor community. To simulate warming, we placed mesocosms of each treatment in ten open-top warming chambers ranging from 1.5° to 5.5°C above ambient at Harvard Forest, Massachusetts, USA. As expected, CO2 emissions increased under warming and we found an interactive effect of predator presence and warming, although the effect was not consistent through time. The interaction between predator presence and warming was the inverse of our predictions: Mesocosms with predators had lower respiration at higher levels of warming than those without predators. Carbon dioxide emissions were not significantly associated with microbial biomass. Here, we did not find evidence of consumptive effects of predators on the invertebrate community, suggesting that predator presence mediates response of microbial respiration to warming through nonconsumptive means. In our system, we found a significant interaction between warming and predator presence that warrants further research into mechanism and generality

  12. Warm storage for arc magmas.

    PubMed

    Barboni, Mélanie; Boehnke, Patrick; Schmitt, Axel K; Harrison, T Mark; Shane, Phil; Bouvier, Anne-Sophie; Baumgartner, Lukas

    2016-12-06

    Felsic magmatic systems represent the vast majority of volcanic activity that poses a threat to human life. The tempo and magnitude of these eruptions depends on the physical conditions under which magmas are retained within the crust. Recently the case has been made that volcanic reservoirs are rarely molten and only capable of eruption for durations as brief as 1,000 years following magma recharge. If the "cold storage" model is generally applicable, then geophysical detection of melt beneath volcanoes is likely a sign of imminent eruption. However, some arc volcanic centers have been active for tens of thousands of years and show evidence for the continual presence of melt. To address this seeming paradox, zircon geochronology and geochemistry from both the frozen lava and the cogenetic enclaves they host from the Soufrière Volcanic Center (SVC), a long-lived volcanic complex in the Lesser Antilles arc, were integrated to track the preeruptive thermal and chemical history of the magma reservoir. Our results show that the SVC reservoir was likely eruptible for periods of several tens of thousands of years or more with punctuated eruptions during these periods. These conclusions are consistent with results from other arc volcanic reservoirs and suggest that arc magmas are generally stored warm. Thus, the presence of intracrustal melt alone is insufficient as an indicator of imminent eruption, but instead represents the normal state of magma storage underneath dormant volcanoes.

  13. Warm storage for arc magmas

    PubMed Central

    Barboni, Mélanie; Schmitt, Axel K.; Harrison, T. Mark; Shane, Phil; Bouvier, Anne-Sophie; Baumgartner, Lukas

    2016-01-01

    Felsic magmatic systems represent the vast majority of volcanic activity that poses a threat to human life. The tempo and magnitude of these eruptions depends on the physical conditions under which magmas are retained within the crust. Recently the case has been made that volcanic reservoirs are rarely molten and only capable of eruption for durations as brief as 1,000 years following magma recharge. If the “cold storage” model is generally applicable, then geophysical detection of melt beneath volcanoes is likely a sign of imminent eruption. However, some arc volcanic centers have been active for tens of thousands of years and show evidence for the continual presence of melt. To address this seeming paradox, zircon geochronology and geochemistry from both the frozen lava and the cogenetic enclaves they host from the Soufrière Volcanic Center (SVC), a long-lived volcanic complex in the Lesser Antilles arc, were integrated to track the preeruptive thermal and chemical history of the magma reservoir. Our results show that the SVC reservoir was likely eruptible for periods of several tens of thousands of years or more with punctuated eruptions during these periods. These conclusions are consistent with results from other arc volcanic reservoirs and suggest that arc magmas are generally stored warm. Thus, the presence of intracrustal melt alone is insufficient as an indicator of imminent eruption, but instead represents the normal state of magma storage underneath dormant volcanoes. PMID:27799558

  14. Global warming: The complete briefing

    SciTech Connect

    Houghton, J.

    1994-12-31

    John Houghton has drawn on the exhaustive efforts of the Intergovernmental Panel on Climate Change (IPCC) to produce a notably compact, impeccably complete and authoritative, meticulously balanced, and lucidly presented guide to the complex yet vital issue of global warming. Its subtitle is not mere hyperbole: this truly is a complete briefing. Certainly, one could not ask for a more authoritative brief: Houghton has led an imposing series of national and international efforts relating to climate, including the most recent scientific assessments of the IPCC. Citing many concrete examples, Houghton begins by convincing that climate truly is important to humankind and that climate is far from constant. He then elucidates the mechanisms that maintain the benign climate of our planet, providing in the process, for example, the most accurate explanation of the natural greenhouse effect that has yet appeared in print. He then treats the individual greenhouse gases responsible for maintaining the earth`s warmth and presents projections of their probable future concentrations as influenced by human activities. Further chapters deal with conclusions drawn from climate models, estimates of the impacts on human activities, and possible policies and actions to mitigate or alleviate the changes and their consequences.

  15. Global warming and reproductive health.

    PubMed

    Potts, Malcolm; Henderson, Courtney E

    2012-10-01

    The largest absolute numbers of maternal deaths occur among the 40-50 million women who deliver annually without a skilled birth attendant. Most of these deaths occur in countries with a total fertility rate of greater than 4. The combination of global warming and rapid population growth in the Sahel and parts of the Middle East poses a serious threat to reproductive health and to food security. Poverty, lack of resources, and rapid population growth make it unlikely that most women in these countries will have access to skilled birth attendants or emergency obstetric care in the foreseeable future. Three strategies can be implemented to improve women's health and reproductive rights in high-fertility, low-resource settings: (1) make family planning accessible and remove non-evidenced-based barriers to contraception; (2) scale up community distribution of misoprostol for prevention of postpartum hemorrhage and, where it is legal, for medical abortion; and (3) eliminate child marriage and invest in girls and young women, thereby reducing early childbearing.

  16. Warm storage for arc magmas

    NASA Astrophysics Data System (ADS)

    Barboni, Mélanie; Boehnke, Patrick; Schmitt, Axel K.; Harrison, T. Mark; Shane, Phil; Bouvier, Anne-Sophie; Baumgartner, Lukas

    2016-12-01

    Felsic magmatic systems represent the vast majority of volcanic activity that poses a threat to human life. The tempo and magnitude of these eruptions depends on the physical conditions under which magmas are retained within the crust. Recently the case has been made that volcanic reservoirs are rarely molten and only capable of eruption for durations as brief as 1,000 years following magma recharge. If the “cold storage” model is generally applicable, then geophysical detection of melt beneath volcanoes is likely a sign of imminent eruption. However, some arc volcanic centers have been active for tens of thousands of years and show evidence for the continual presence of melt. To address this seeming paradox, zircon geochronology and geochemistry from both the frozen lava and the cogenetic enclaves they host from the Soufrière Volcanic Center (SVC), a long-lived volcanic complex in the Lesser Antilles arc, were integrated to track the preeruptive thermal and chemical history of the magma reservoir. Our results show that the SVC reservoir was likely eruptible for periods of several tens of thousands of years or more with punctuated eruptions during these periods. These conclusions are consistent with results from other arc volcanic reservoirs and suggest that arc magmas are generally stored warm. Thus, the presence of intracrustal melt alone is insufficient as an indicator of imminent eruption, but instead represents the normal state of magma storage underneath dormant volcanoes.

  17. On the two tales of Warm Jupiters

    NASA Astrophysics Data System (ADS)

    Huang, Chelsea; Wu, Yanqin

    2017-06-01

    Warm Jupiters often refer to giant planets with intermediate orbit periods between 10-200 days. Their period range corresponds to the so-called "period valley", the observed dip in occupation in-between the hot Jupiters and cold Jupiters. Observational evidences suggest that they are a distinct population from the hot Jupiters and are likely to be formed from at least two different channels themselves. Earlier radial velocity surveys show that at least a fraction of the warm Jupiters have modest to high eccentricities, supporting these planets migrate to their current location through either secular perturbations or planet-planet scatterings. On the other hand, transiting warm Jupiters found in Kepler are likely to have close-by transiting low mass companions interior/exterior to the warm Jupiter orbits. The existence of the companions indicating the system needs to be near coplanar, and near circular, unlike their radial velocity counter parts. In this talk, I will review observational properties to date of the warm Jupiters, as well as recent advances in the theory of the warm Jupiter formation. I will then discuss how new discoveries from TESS can help with understanding the transition between the hot and warm Jupiter population, and distinguish the contribution from different formation channels.

  18. Global metabolic impacts of recent climate warming.

    PubMed

    Dillon, Michael E; Wang, George; Huey, Raymond B

    2010-10-07

    Documented shifts in geographical ranges, seasonal phenology, community interactions, genetics and extinctions have been attributed to recent global warming. Many such biotic shifts have been detected at mid- to high latitudes in the Northern Hemisphere-a latitudinal pattern that is expected because warming is fastest in these regions. In contrast, shifts in tropical regions are expected to be less marked because warming is less pronounced there. However, biotic impacts of warming are mediated through physiology, and metabolic rate, which is a fundamental measure of physiological activity and ecological impact, increases exponentially rather than linearly with temperature in ectotherms. Therefore, tropical ectotherms (with warm baseline temperatures) should experience larger absolute shifts in metabolic rate than the magnitude of tropical temperature change itself would suggest, but the impact of climate warming on metabolic rate has never been quantified on a global scale. Here we show that estimated changes in terrestrial metabolic rates in the tropics are large, are equivalent in magnitude to those in the north temperate-zone regions, and are in fact far greater than those in the Arctic, even though tropical temperature change has been relatively small. Because of temperature's nonlinear effects on metabolism, tropical organisms, which constitute much of Earth's biodiversity, should be profoundly affected by recent and projected climate warming.

  19. Relative roles of differential SST warming, uniform SST warming and land surface warming in determining the Walker circulation changes under global warming

    NASA Astrophysics Data System (ADS)

    Zhang, Lei; Li, Tim

    2017-02-01

    Most of CMIP5 models projected a weakened Walker circulation in tropical Pacific, but what causes such change is still an open question. By conducting idealized numerical simulations separating the effects of the spatially uniform sea surface temperature (SST) warming, extra land surface warming and differential SST warming, we demonstrate that the weakening of the Walker circulation is attributed to the western North Pacific (WNP) monsoon and South America land effects. The effect of the uniform SST warming is through so-called "richest-get-richer" mechanism. In response to a uniform surface warming, the WNP monsoon is enhanced by competing moisture with other large-scale convective branches. The strengthened WNP monsoon further induces surface westerlies in the equatorial western-central Pacific, weakening the Walker circulation. The increase of the greenhouse gases leads to a larger land surface warming than ocean surface. As a result, a greater thermal contrast occurs between American Continent and equatorial Pacific. The so-induced zonal pressure gradient anomaly forces low-level westerly anomalies over the equatorial eastern Pacific and weakens the Walker circulation. The differential SST warming also plays a role in driving low-level westerly anomalies over tropical Pacific. But such an effect involves a positive air-sea feedback that amplifies the weakening of both east-west SST gradient and Pacific trade winds.

  20. Climatic warming destabilizes forest ant communities

    PubMed Central

    Diamond, Sarah E.; Nichols, Lauren M.; Pelini, Shannon L.; Penick, Clint A.; Barber, Grace W.; Cahan, Sara Helms; Dunn, Robert R.; Ellison, Aaron M.; Sanders, Nathan J.; Gotelli, Nicholas J.

    2016-01-01

    How will ecological communities change in response to climate warming? Direct effects of temperature and indirect cascading effects of species interactions are already altering the structure of local communities, but the dynamics of community change are still poorly understood. We explore the cumulative effects of warming on the dynamics and turnover of forest ant communities that were warmed as part of a 5-year climate manipulation experiment at two sites in eastern North America. At the community level, warming consistently increased occupancy of nests and decreased extinction and nest abandonment. This consistency was largely driven by strong responses of a subset of thermophilic species at each site. As colonies of thermophilic species persisted in nests for longer periods of time under warmer temperatures, turnover was diminished, and species interactions were likely altered. We found that dynamical (Lyapunov) community stability decreased with warming both within and between sites. These results refute null expectations of simple temperature-driven increases in the activity and movement of thermophilic ectotherms. The reduction in stability under warming contrasts with the findings of previous studies that suggest resilience of species interactions to experimental and natural warming. In the face of warmer, no-analog climates, communities of the future may become increasingly fragile and unstable. PMID:27819044

  1. Relative roles of differential SST warming, uniform SST warming and land surface warming in determining the Walker circulation changes under global warming

    NASA Astrophysics Data System (ADS)

    Zhang, Lei; Li, Tim

    2016-04-01

    Most of CMIP5 models projected a weakened Walker circulation in tropical Pacific, but what causes such change is still an open question. By conducting idealized numerical simulations separating the effects of the spatially uniform sea surface temperature (SST) warming, extra land surface warming and differential SST warming, we demonstrate that the weakening of the Walker circulation is attributed to the western North Pacific (WNP) monsoon and South America land effects. The effect of the uniform SST warming is through so-called "richest-get-richer" mechanism. In response to a uniform surface warming, the WNP monsoon is enhanced by competing moisture with other large-scale convective branches. The strengthened WNP monsoon further induces surface westerlies in the equatorial western-central Pacific, weakening the Walker circulation. The increase of the greenhouse gases leads to a larger land surface warming than ocean surface. As a result, a greater thermal contrast occurs between American Continent and equatorial Pacific. The so-induced zonal pressure gradient anomaly forces low-level westerly anomalies over the equatorial eastern Pacific and weakens the Walker circulation. The differential SST warming also plays a role in driving low-level westerly anomalies over tropical Pacific. But such an effect involves a positive air-sea feedback that amplifies the weakening of both east-west SST gradient and Pacific trade winds.

  2. Significant warming of the Antarctic winter troposphere.

    PubMed

    Turner, J; Lachlan-Cope, T A; Colwell, S; Marshall, G J; Connolley, W M

    2006-03-31

    We report an undocumented major warming of the Antarctic winter troposphere that is larger than any previously identified regional tropospheric warming on Earth. This result has come to light through an analysis of recently digitized and rigorously quality controlled Antarctic radiosonde observations. The data show that regional midtropospheric temperatures have increased at a statistically significant rate of 0.5 degrees to 0.7 degrees Celsius per decade over the past 30 years. Analysis of the time series of radiosonde temperatures indicates that the data are temporally homogeneous. The available data do not allow us to unambiguously assign a cause to the tropospheric warming at this stage.

  3. Global Warming Estimation from MSU

    NASA Technical Reports Server (NTRS)

    Prabhakara, C.; Iacovazzi, Robert; Yoo, Jung-Moon

    1998-01-01

    Microwave Sounding Unit (MSU) radiometer observations in Ch 2 (53.74 GHz) from sequential, sun-synchronous, polar-orbiting NOAA satellites contain small systematic errors. Some of these errors are time-dependent and some are time-independent. Small errors in Ch 2 data of successive satellites arise from calibration differences. Also, successive NOAA satellites tend to have different Local Equatorial Crossing Times (LECT), which introduce differences in Ch 2 data due to the diurnal cycle. These two sources of systematic error are largely time independent. However, because of atmospheric drag, there can be a drift in the LECT of a given satellite, which introduces time-dependent systematic errors. One of these errors is due to the progressive chance in the diurnal cycle and the other is due to associated chances in instrument heating by the sun. In order to infer global temperature trend from the these MSU data, we have eliminated explicitly the time-independent systematic errors. Both of the time-dependent errors cannot be assessed from each satellite. For this reason, their cumulative effect on the global temperature trend is evaluated implicitly. Christy et al. (1998) (CSL). based on their method of analysis of the MSU Ch 2 data, infer a global temperature cooling trend (-0.046 K per decade) from 1979 to 1997, although their near nadir measurements yield near zero trend (0.003 K/decade). Utilising an independent method of analysis, we infer global temperature warmed by 0.12 +/- 0.06 C per decade from the observations of the MSU Ch 2 during the period 1980 to 1997.

  4. Global Warming Estimation from MSU

    NASA Technical Reports Server (NTRS)

    Prabhakara, C.; Iacovazzi, Robert; Yoo, Jung-Moon

    1998-01-01

    Microwave Sounding Unit (MSU) radiometer observations in Ch 2 (53.74 GHz) from sequential, sun-synchronous, polar-orbiting NOAA satellites contain small systematic errors. Some of these errors are time-dependent and some are time-independent. Small errors in Ch 2 data of successive satellites arise from calibration differences. Also, successive NOAA satellites tend to have different Local Equatorial Crossing Times (LECT), which introduce differences in Ch 2 data due to the diurnal cycle. These two sources of systematic error are largely time independent. However, because of atmospheric drag, there can be a drift in the LECT of a given satellite, which introduces time-dependent systematic errors. One of these errors is due to the progressive chance in the diurnal cycle and the other is due to associated chances in instrument heating by the sun. In order to infer global temperature trend from the these MSU data, we have eliminated explicitly the time-independent systematic errors. Both of the time-dependent errors cannot be assessed from each satellite. For this reason, their cumulative effect on the global temperature trend is evaluated implicitly. Christy et al. (1998) (CSL). based on their method of analysis of the MSU Ch 2 data, infer a global temperature cooling trend (-0.046 K per decade) from 1979 to 1997, although their near nadir measurements yield near zero trend (0.003 K/decade). Utilising an independent method of analysis, we infer global temperature warmed by 0.12 +/- 0.06 C per decade from the observations of the MSU Ch 2 during the period 1980 to 1997.

  5. Atmospheric science: Warming boosts air pollution

    NASA Astrophysics Data System (ADS)

    Zhang, Renhe

    2017-03-01

    Atmospheric conditions play an important role in driving severe air pollution events in Beijing, China. Now research finds that global warming will enhance weather conditions favouring such events, increasing the chances of severe winter-time haze in the future.

  6. Reconciling controversies about the 'global warming hiatus'.

    PubMed

    Medhaug, Iselin; Stolpe, Martin B; Fischer, Erich M; Knutti, Reto

    2017-05-03

    Between about 1998 and 2012, a time that coincided with political negotiations for preventing climate change, the surface of Earth seemed hardly to warm. This phenomenon, often termed the 'global warming hiatus', caused doubt in the public mind about how well anthropogenic climate change and natural variability are understood. Here we show that apparently contradictory conclusions stem from different definitions of 'hiatus' and from different datasets. A combination of changes in forcing, uptake of heat by the oceans, natural variability and incomplete observational coverage reconciles models and data. Combined with stronger recent warming trends in newer datasets, we are now more confident than ever that human influence is dominant in long-term warming.

  7. Chamberless residential warm air furnace design

    SciTech Connect

    Godfree, J.

    1996-07-01

    This brief paper is an introduction to the concept of designing residential warm air furnaces without combustion chambers. This is possible since some small burners do not require the thermal support of a combustion chamber to complete the combustion process.

  8. Palaeoclimate: Volcanism caused ancient global warming

    NASA Astrophysics Data System (ADS)

    Meissner, Katrin J.; Bralower, Timothy J.

    2017-08-01

    A study confirms that volcanism set off one of Earth's fastest global-warming events. But the release of greenhouse gases was slow enough for negative feedbacks to mitigate impacts such as ocean acidification. See Letter p.573

  9. Warming up and cooling down (image)

    MedlinePlus

    ... the exercise itself. By properly warming up the muscles and joints with low-level aerobic movement for 5 to 10 minutes, one may avoid injury and build endurance over time. Cooling down after exercise by walking ...

  10. Carbon cycle: Global warming then and now

    NASA Astrophysics Data System (ADS)

    Stassen, Peter

    2016-04-01

    A rapid warming event 55.8 million years ago was caused by extensive carbon emissions. The rate of change of carbon and oxygen isotopes in marine shelf sediments suggests that carbon emission rates were much slower than anthropogenic emissions.

  11. Global temperatures and the global warming ``debate''

    NASA Astrophysics Data System (ADS)

    Aubrecht, Gordon

    2009-04-01

    Many ordinary citizens listen to pronouncements on talk radio casting doubt on anthropogenic global warming. Some op-ed columnists likewise cast doubts, and are read by credulous citizens. For example, on 8 March 2009, the Boston Globe published a column by Jeff Jacoby, ``Where's global warming?'' According to Jacoby, ``But it isn't such hints of a planetary warming trend that have been piling up in profusion lately. Just the opposite.'' He goes on to write, ``the science of climate change is not nearly as important as the religion of climate change,'' and blamed Al Gore for getting his mistaken views accepted. George Will at the Washington Post also expressed denial. As a result, 44% of U.S. voters, according to the January 19 2009 Rasmussen Report, blame long-term planetary trends for global warming, not human beings. Is there global cooling, as skeptics claim? We examine the temperature record.

  12. Should we be concerned about global warming?

    PubMed

    Diaz, James H

    2006-01-01

    Accurate scientific predictions of the true human health outcomes of global climate change are significantly confounded by several effect modifiers that cannot be adjusted for analytically. Nevertheless, with the documented increase in average global surface temperature of 0.6 C. since 1975, there is uniform consensus in the international scientific community that the earth is warming from a variety of climatic effects, including cyclical re-warming and the cascading effects of greenhouse gas emissions to support human activities.

  13. Scaling Potential Evapotranspiration with Greenhouse Warming (Invited)

    NASA Astrophysics Data System (ADS)

    Scheff, J.; Frierson, D. M.

    2013-12-01

    Potential evapotranspiration (PET) is a supply-independent measure of the evaporative demand of a terrestrial climate, of basic importance in climatology, hydrology, and agriculture. Future increases in PET from greenhouse warming are often cited as key drivers of global trends toward drought and aridity. The present work computes recent and business-as-usual-future Penman-Monteith (i.e. physically-based) PET fields at 3-hourly resolution in 14 modern global climate models. The %-change in local annual-mean PET over the upcoming century is almost always positive, modally low double-digit in magnitude, usually increasing with latitude, yet quite divergent between models. These patterns are understood as follows. In every model, the global field of PET %-change is found to be dominated by the direct, positive effects of constant-relative-humidity warming (via increasing vapor pressure deficit and increasing Clausius-Clapeyron slope.) This direct-warming term very accurately scales as the PET-weighted (warm-season daytime) local warming, times 5-6% per degree (related to the Clausius-Clapeyron equation), times an analytic factor ranging from about 0.25 in warm climates to 0.75 in cold climates, plus a small correction. With warming of several degrees, this product is of low double-digit magnitude, and the strong temperature dependence gives the latitude dependence. Similarly, the inter-model spread in the amount of warming gives most of the spread in this term. Additional spread in the total change comes from strong disagreement on radiation, relative-humidity, and windspeed changes, which make smaller yet substantial contributions to the full PET %-change fields.

  14. The Tropical Western Hemisphere Warm Pool

    NASA Astrophysics Data System (ADS)

    Wang, C.; Enfield, D. B.

    2002-12-01

    The paper describes and examines variability of the tropical Western Hemisphere warm pool (WHWP) of water warmer than 28.5oC. The WHWP is the second-largest tropical warm pool on Earth. Unlike the Eastern Hemisphere warm pool in the western Pacific, which straddles the equator, the WHWP is entirely north of the equator. At various stages of development the WHWP extends over parts of the eastern North Pacific, the Gulf of Mexico, the Caribbean, and the western tropical North Atlantic. It has a large seasonal cycle and its interannual fluctuations of area and intensity are significant. Surface heat fluxes warm the WHWP through the boreal spring to an annual maximum of SST and WHWP area in the late summer/early fall, associated with eastern North Pacific and Atlantic hurricane activities and rainfall from northern South America to the southern tier of the United States. Observations suggest that a positive ocean-atmosphere feedback operating through longwave radiation and associated cloudiness seems to operate in the WHWP. During winter preceding large warm pool, there is an alteration of the Walker and Hadley circulation cells that serves as a "tropospheric bridge" for transferring Pacific ENSO effects to the Atlantic sector and inducing initial warming of warm pool. Associated with the warm SST anomalies is a decrease in sea level pressure anomalies and an anomalous increase in atmospheric convection and cloudiness. The increase in convective activity and cloudiness results in less net longwave radiation loss from the sea surface, which then reinforces SST anomalies.

  15. Analysis of warm prestress data

    SciTech Connect

    Macdonald, B.D.; Embley, G.T.; Irizarry-Quinones, H.; Smith, P.D.; Wuthrich, J.W.; McAfee, W.J.; McCabe, D.E.

    1995-06-01

    Loading a cracked structure at elevated temperature, or warm prestressing (WPS), enhances its fracture resistance at a lower temperature. Five data sets, comprising 119 unclad pressure vessel steel specimens, were combined to derive correlations for WPS-enhanced fracture toughness (K{sub Ifrac}) in the absence of ductile tearing. New WPS test results for 27 surface flawed specimens, eight subclad flawed specimens, and five strain-aged specimens are discussed. K{sub Ifrac} exceeded non-WPS fracture toughness, K{sub Ic}, for all experiments. The WPS data showed that no specimens failed while K was decreasing, and that at least an additional seven percent additional reloading from the minimum value of applied K{sub I} took place prior to final fracture. The data included complete and partial unloading after WPS prior to final fracture. Crack tip 3-dimensional elastic-plastic finite element (3DEPFE) analysis was performed to support statistical analysis of the data. Regression models were compared with the Chell WPS model. Crack tip 3DEPFE analysis indicated that partially unloaded and completely unloaded data should be treated separately, and that the amount of unloading is unimportant for partially unloaded data. The regression models, which use K{sub I} at WPS (K{sub Iwps}) and K{sub Ic} as independent variables, better represented the WPS benefit than did the more complicated Chell model. An adequate accounting was made for constraint in the WPS experiments. The subclad flaw data support the use of the partial unload regression model, provided that some care is taken to represent the effect of intact cladding if present. The effect of strain aging at or below 260 C (500 F) on WPS benefit was of no consequence for the pressure vessel steels and WPS temperatures used to derive the regression models. The presence of ductile tearing precludes the use of the regression models. The regression model for partial unloading accurately predicted the behavior of full scale

  16. Global warming and nuclear power

    SciTech Connect

    Wood, L., LLNL

    1998-07-10

    -fold reduction might be attained. Even the first such halving of carbon intensivity of stationary-source energy production world-wide might permit continued slow power-demand growth in the highly developed countries and rapid development of the other 80% of the world, both without active governmental suppression of fossil fuel usage - while also stabilizing carbon input-rates into the Earth`s atmosphere. The second two-fold reduction might obviate most global warming concerns.

  17. Global warming: a vicious circle.

    PubMed

    Sinclair, J

    1991-01-01

    The problem of global warming (GW) is larger than it was originally suspected. The release of carbon dioxide (CO2), methane (ME), and nitrous oxide (NO2) by the activities of humans will do more than simply raise the global temperature. It will also trigger a variety of feedback loops that will accelerate the GW process. The extent of these feedback loops is currently impossible to incorporate into the computer models because they are not fully understood. But, from what we do know, it is clear that reductions in greenhouse gas (GG) emissions must be halted immediately. We are already committed to regional droughts, storms, water shortages, fishery disruptions and plant and animal extinctions. But the response of the oceans, forest, and ice masses has not yet been incorporated into our predictions. Almost all the feedbacks identified promise to increase GG concentrations. The carbon cycle is going to be affected in a variety of ways. Plants and soil store almost 3 times the CO2 as found in the atmosphere. Increased temperatures will increase plant respiration, thus increasing CO2 emissions. Forests will die, permafrost will melt and the result will be increased releases of CO2 and ME. The oceans and plankton can not absorb as much CO2 as the water temperature rises. At present levels GG concentrations will double by 2025. Thus scientists are calling for an immediate 60-80% reduction in CO2 and other GG emissions. It is up to the industrialized nations to solve this problem since they are the ones who created it. 75% of all human made CO2 comes from these countries. They also have the ability to help developing nations to do the same. 20 nations have already announced plans to stabilize or reduce their GG emissions, but it is attitudes and lifestyles that must be changed. This is the largest problem to ever face the human race and never before have we acted as we now must act in order to avoid a worldwide catastrophe.

  18. Could cirrus clouds have warmed early Mars?

    NASA Astrophysics Data System (ADS)

    Ramirez, Ramses M.; Kasting, James F.

    2017-01-01

    The presence of the ancient valley networks on Mars indicates that the climate at 3.8 Ga was warm enough to allow substantial liquid water to flow on the martian surface for extended periods of time. However, the mechanism for producing this warming continues to be debated. One hypothesis is that Mars could have been kept warm by global cirrus cloud decks in a CO2sbnd H2O atmosphere containing at least 0.25 bar of CO2 (Urata and Toon, 2013). Initial warming from some other process, e.g., impacts, would be required to make this model work. Those results were generated using the CAM 3-D global climate model. Here, we use a single-column radioactive-convective climate model to further investigate the cirrus cloud warming hypothesis. Our calculations indicate that cirrus cloud decks could have produced global mean surface temperatures above freezing, but only if cirrus cloud cover approaches ∼75 - 100% and if other cloud properties (e.g., height, optical depth, particle size) are chosen favorably. However, at more realistic cirrus cloud fractions, or if cloud parameters are not optimal, cirrus clouds do not provide the necessary warming, suggesting that other greenhouse mechanisms are needed.

  19. Is global warming harmful to health?

    PubMed

    Epstein, P R

    2000-08-01

    Projections from computer models predict that global warming will expand the incidence and distribution of many serious medical disorders. Global warming, aside from indirectly causing death by drowning or starvation, promotes by various means the emergence, resurgence, and spread of infectious diseases. This article addresses the health effects of global warming and disrupted climate patterns in detail. Among the greatest health concerns are diseases transmitted by mosquitoes, such as malaria, dengue fever, yellow fever, and several kinds of encephalitis. Such disorders are projected to become increasingly prevalent because their insect carriers are very sensitive to meteorological conditions. In addition, floods and droughts resulting from global warming can each help trigger outbreaks by creating breeding grounds for insects whose desiccated eggs remain viable and hatch in still water. Other effects of global warming on health include the growth of opportunist populations and the increase of the incidence of waterborne diseases because of lack of clean water. In view of this, several steps are cited in order to facilitate the successful management of the dangers of global warming.

  20. Warming shifts 'worming': effects of experimental warming on invasive earthworms in northern North America.

    PubMed

    Eisenhauer, Nico; Stefanski, Artur; Fisichelli, Nicholas A; Rice, Karen; Rich, Roy; Reich, Peter B

    2014-11-03

    Climate change causes species range shifts and potentially alters biological invasions. The invasion of European earthworm species across northern North America has severe impacts on native ecosystems. Given the long and cold winters in that region that to date supposedly have slowed earthworm invasion, future warming is hypothesized to accelerate earthworm invasions into yet non-invaded regions. Alternatively, warming-induced reductions in soil water content (SWC) can also decrease earthworm performance. We tested these hypotheses in a field warming experiment at two sites in Minnesota, USA by sampling earthworms in closed and open canopy in three temperature treatments in 2010 and 2012. Structural equation modeling revealed that detrimental warming effects on earthworm densities and biomass could indeed be partly explained by warming-induced reductions in SWC. The direction of warming effects depended on the current average SWC: warming had neutral to positive effects at high SWC, whereas the opposite was true at low SWC. Our results suggest that warming limits the invasion of earthworms in northern North America by causing less favorable soil abiotic conditions, unless warming is accompanied by increased and temporally even distributions of rainfall sufficient to offset greater water losses from higher evapotranspiration.

  1. Warming shifts `worming': effects of experimental warming on invasive earthworms in northern North America

    NASA Astrophysics Data System (ADS)

    Eisenhauer, Nico; Stefanski, Artur; Fisichelli, Nicholas A.; Rice, Karen; Rich, Roy; Reich, Peter B.

    2014-11-01

    Climate change causes species range shifts and potentially alters biological invasions. The invasion of European earthworm species across northern North America has severe impacts on native ecosystems. Given the long and cold winters in that region that to date supposedly have slowed earthworm invasion, future warming is hypothesized to accelerate earthworm invasions into yet non-invaded regions. Alternatively, warming-induced reductions in soil water content (SWC) can also decrease earthworm performance. We tested these hypotheses in a field warming experiment at two sites in Minnesota, USA by sampling earthworms in closed and open canopy in three temperature treatments in 2010 and 2012. Structural equation modeling revealed that detrimental warming effects on earthworm densities and biomass could indeed be partly explained by warming-induced reductions in SWC. The direction of warming effects depended on the current average SWC: warming had neutral to positive effects at high SWC, whereas the opposite was true at low SWC. Our results suggest that warming limits the invasion of earthworms in northern North America by causing less favorable soil abiotic conditions, unless warming is accompanied by increased and temporally even distributions of rainfall sufficient to offset greater water losses from higher evapotranspiration.

  2. The importance of warm season warming to western U.S. streamflow changes

    USGS Publications Warehouse

    Das, T.; Pierce, D.W.; Cayan, D.R.; Vano, J.A.; Lettenmaier, D.P.

    2011-01-01

    Warm season climate warming will be a key driver of annual streamflow changes in four major river basins of the western U.S., as shown by hydrological model simulations using fixed precipitation and idealized seasonal temperature changes based on climate projections with SRES A2 forcing. Warm season (April-September) warming reduces streamflow throughout the year; streamflow declines both immediately and in the subsequent cool season. Cool season (October-March) warming, by contrast, increases streamflow immediately, partially compensating for streamflow reductions during the subsequent warm season. A uniform warm season warming of 3C drives a wide range of annual flow declines across the basins: 13.3%, 7.2%, 1.8%, and 3.6% in the Colorado, Columbia, Northern and Southern Sierra basins, respectively. The same warming applied during the cool season gives annual declines of only 3.5%, 1.7%, 2.1%, and 3.1%, respectively. Copyright 2011 by the American Geophysical Union.

  3. Warming shifts ‘worming': effects of experimental warming on invasive earthworms in northern North America

    PubMed Central

    Eisenhauer, Nico; Stefanski, Artur; Fisichelli, Nicholas A.; Rice, Karen; Rich, Roy; Reich, Peter B.

    2014-01-01

    Climate change causes species range shifts and potentially alters biological invasions. The invasion of European earthworm species across northern North America has severe impacts on native ecosystems. Given the long and cold winters in that region that to date supposedly have slowed earthworm invasion, future warming is hypothesized to accelerate earthworm invasions into yet non-invaded regions. Alternatively, warming-induced reductions in soil water content (SWC) can also decrease earthworm performance. We tested these hypotheses in a field warming experiment at two sites in Minnesota, USA by sampling earthworms in closed and open canopy in three temperature treatments in 2010 and 2012. Structural equation modeling revealed that detrimental warming effects on earthworm densities and biomass could indeed be partly explained by warming-induced reductions in SWC. The direction of warming effects depended on the current average SWC: warming had neutral to positive effects at high SWC, whereas the opposite was true at low SWC. Our results suggest that warming limits the invasion of earthworms in northern North America by causing less favorable soil abiotic conditions, unless warming is accompanied by increased and temporally even distributions of rainfall sufficient to offset greater water losses from higher evapotranspiration. PMID:25363633

  4. Can Global Warming be Stopped?

    NASA Astrophysics Data System (ADS)

    Luria, M.

    2013-12-01

    Earlier this year, the CO2 levels exceeded the 400 ppm level and there is no sign that the 1-2 ppm annual increase is going to slow down. Concerns regarding the danger of global warming have been reported in numerous occasions for more than a generation, ever since CO2 levels reached the 350 ppm range in the mid 1980's. Nevertheless, all efforts to slow down the increase have showed little if any effect. Mobile sources, including surface and marine transportation and aviation, consist of 20% of the global CO2 emission. The only realistic way to reduce the mobile sources' CO2 signature is by improved fuel efficiency. However, any progress in this direction is more than compensated by continuous increased demand. Stationary sources, mostly electric power generation, are responsible for the bulk of the global CO2 emission. The measurements have shown, that the effect of an increase in renewable sources, like solar wind and geothermal, combined with conversion from coal to natural gas where possible, conservation and efficiency improvement, did not compensate the increased demand mostly in developing countries. Increased usage of nuclear energy can provide some relief in carbon emission but has the potential of even greater environmental hazard. A major decrease in carbon emission can be obtained by either significant reduction in the cost of non-carbon based energy sources or by of carbon sequestration. The most economical way to make a significant decrease in carbon emission is to apply carbon sequestration technology at large point sources that use coal. Worldwide there are about 10,000 major sources that burn >7 billion metric tons of coal which generate the equivalent of 30 trillion kwh. There is a limited experience in CO2 sequestration of such huge quantities of CO2, however, it is estimated that the cost would be US$ 0.01-0.1 per kwh. The cost of eliminating this quantity can be estimated at an average of 1.5 trillion dollars annually. The major emitters, US

  5. 21 CFR 864.9205 - Blood and plasma warming device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Blood and plasma warming device. 864.9205 Section... Blood and Blood Products § 864.9205 Blood and plasma warming device. (a) Nonelectromagnetic blood or plasma warming device—(1) Identification. A nonelectromagnetic blood and plasma warming device is a...

  6. 21 CFR 864.9205 - Blood and plasma warming device.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Blood and plasma warming device. 864.9205 Section... Blood and Blood Products § 864.9205 Blood and plasma warming device. (a) Nonelectromagnetic blood or plasma warming device—(1) Identification. A nonelectromagnetic blood and plasma warming device is...

  7. 21 CFR 864.9205 - Blood and plasma warming device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Blood and plasma warming device. 864.9205 Section... Blood and Blood Products § 864.9205 Blood and plasma warming device. (a) Nonelectromagnetic blood or plasma warming device—(1) Identification. A nonelectromagnetic blood and plasma warming device is a...

  8. 21 CFR 864.9205 - Blood and plasma warming device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Blood and plasma warming device. 864.9205 Section... Blood and Blood Products § 864.9205 Blood and plasma warming device. (a) Nonelectromagnetic blood or plasma warming device—(1) Identification. A nonelectromagnetic blood and plasma warming device is a...

  9. 21 CFR 864.9205 - Blood and plasma warming device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Blood and plasma warming device. 864.9205 Section... Blood and Blood Products § 864.9205 Blood and plasma warming device. (a) Nonelectromagnetic blood or plasma warming device—(1) Identification. A nonelectromagnetic blood and plasma warming device is a...

  10. Warm Absorber Diagnostics of AGN Dynamics

    NASA Astrophysics Data System (ADS)

    Kallman, Timothy

    Warm absorbers and related phenomena are observable manifestations of outflows or winds from active galactic nuclei (AGN) that have great potential value. Understanding AGN outflows is important for explaining the mass budgets of the central accreting black hole, and also for understanding feedback and the apparent co-evolution of black holes and their host galaxies. In the X-ray band warm absorbers are observed as photoelectric absorption and resonance line scattering features in the 0.5-10 keV energy band; the UV band also shows resonance line absorption. Warm absorbers are common in low luminosity AGN and they have been extensively studied observationally. They may play an important role in AGN feedback, regulating the net accretion onto the black hole and providing mechanical energy to the surroundings. However, fundamental properties of the warm absorbers are not known: What is the mechanism which drives the outflow?; what is the gas density in the flow and the geometrical distribution of the outflow?; what is the explanation for the apparent relation between warm absorbers and the surprising quasi-relativistic 'ultrafast outflows' (UFOs)? We propose a focused set of model calculations that are aimed at synthesizing observable properties of warm absorber flows and associated quantities. These will be used to explore various scenarios for warm absorber dynamics in order to answer the questions in the previous paragraph. The guiding principle will be to examine as wide a range as possible of warm absorber driving mechanisms, geometry and other properties, but with as careful consideration as possible to physical consistency. We will build on our previous work, which was a systematic campaign for testing important class of scenarios for driving the outflows. We have developed a set of tools that are unique and well suited for dynamical calculations including radiation in this context. We also have state-of-the-art tools for generating synthetic spectra, which are

  11. Light accelerates plant responses to warming.

    PubMed

    De Frenne, Pieter; Rodríguez-Sánchez, Francisco; De Schrijver, An; Coomes, David A; Hermy, Martin; Vangansbeke, Pieter; Verheyen, Kris

    2015-08-17

    Competition for light has profound effects on plant performance in virtually all terrestrial ecosystems. Nowhere is this more evident than in forests, where trees create environmental heterogeneity that shapes the dynamics of forest-floor communities(1-3). Observational evidence suggests that biotic responses to both anthropogenic global warming and nitrogen pollution may be attenuated by the shading effects of trees and shrubs(4-9). Here we show experimentally that tree shade is slowing down changes in below-canopy communities due to warming. We manipulated levels of photosynthetically active radiation, temperature and nitrogen, alone and in combination, in a temperate forest understorey over a 3-year period, and monitored the composition of the understorey community. Light addition, but not nitrogen enrichment, accelerated directional plant community responses to warming, increasing the dominance of warmth-preferring taxa over cold-tolerant plants (a process described as thermophilization(6,10-12)). Tall, competitive plants took greatest advantage of the combination of elevated temperature and light. Warming of the forest floor did not result in strong community thermophilization unless light was also increased. Our findings suggest that the maintenance of locally closed canopy conditions could reduce, at least temporarily, warming-induced changes in forest floor plant communities.

  12. The equable climate problem during Interglacial warming

    NASA Astrophysics Data System (ADS)

    Davis, B. A.; Mauri, A.; Brewer, S.; Gajewski, K. J.; Kühl, N.; Viau, A. E.; Wu, H.; Kaplan, J. O.

    2011-12-01

    Considerable evidence indicates that warmer climates prior to the Pleistocene glacial-interglacial cycles were more equable, characterised by 1) a smaller equator-pole temperature gradient, and 2) a smaller temperature difference between winter and summer, especially in the interior of the continents. Future climate is also expected to be more equable, but climate models continue to have difficulty simulating this aspect of pre-Pleistocene climates. The equable nature of more recent interglacial warming has received little attention despite being much more accessible, largely because earlier studies have focussed mainly on summer season temperature changes over high latitudes. Here we use a comprehensive synthesis of published marine and terrestrial proxy-data to reconstruct the pattern of both summer and winter temperature anomalies, and the equator-pole temperature gradient, during the warmer conditions of the Mid-Holocene (6 ka), and the Last Interglacial (125 ka) over the Northern Hemisphere. Comparing these results with climate model simulations we find two major paradoxes that are not reproduced in models; 1) winter warming was greater than summer warming, despite contrary insolation forcing, and 2) this strong winter warming was largely the result of a stronger atmospheric circulation comparable with a high index Northern Annular Mode (NAM), despite a weaker equator-pole temperature gradient at this time. These paradoxes present the same equable climate problem that characterise much earlier and warmer climates, adding to uncertainties in the ability of climate models to simulate the equable nature of future climate warming.

  13. Global warming without global mean precipitation increase?

    PubMed Central

    Salzmann, Marc

    2016-01-01

    Global climate models simulate a robust increase of global mean precipitation of about 1.5 to 2% per kelvin surface warming in response to greenhouse gas (GHG) forcing. Here, it is shown that the sensitivity to aerosol cooling is robust as well, albeit roughly twice as large. This larger sensitivity is consistent with energy budget arguments. At the same time, it is still considerably lower than the 6.5 to 7% K−1 decrease of the water vapor concentration with cooling from anthropogenic aerosol because the water vapor radiative feedback lowers the hydrological sensitivity to anthropogenic forcings. When GHG and aerosol forcings are combined, the climate models with a realistic 20th century warming indicate that the global mean precipitation increase due to GHG warming has, until recently, been completely masked by aerosol drying. This explains the apparent lack of sensitivity of the global mean precipitation to the net global warming recently found in observations. As the importance of GHG warming increases in the future, a clear signal will emerge. PMID:27386558

  14. Global warming without global mean precipitation increase?

    PubMed

    Salzmann, Marc

    2016-06-01

    Global climate models simulate a robust increase of global mean precipitation of about 1.5 to 2% per kelvin surface warming in response to greenhouse gas (GHG) forcing. Here, it is shown that the sensitivity to aerosol cooling is robust as well, albeit roughly twice as large. This larger sensitivity is consistent with energy budget arguments. At the same time, it is still considerably lower than the 6.5 to 7% K(-1) decrease of the water vapor concentration with cooling from anthropogenic aerosol because the water vapor radiative feedback lowers the hydrological sensitivity to anthropogenic forcings. When GHG and aerosol forcings are combined, the climate models with a realistic 20th century warming indicate that the global mean precipitation increase due to GHG warming has, until recently, been completely masked by aerosol drying. This explains the apparent lack of sensitivity of the global mean precipitation to the net global warming recently found in observations. As the importance of GHG warming increases in the future, a clear signal will emerge.

  15. Warm eyes provide superior vision in swordfishes.

    PubMed

    Fritsches, Kerstin A; Brill, Richard W; Warrant, Eric J

    2005-01-11

    Large and powerful ocean predators such as swordfishes, some tunas, and several shark species are unique among fishes in that they are capable of maintaining elevated body temperatures (endothermy) when hunting for prey in deep and cold water . In these animals, warming the central nervous system and the eyes is the one common feature of this energetically costly adaptation . In the swordfish (Xiphias gladius), a highly specialized heating system located in an extraocular muscle specifically warms the eyes and brain up to 10 degrees C-15 degrees C above ambient water temperatures . Although the function of neural warming in fishes has been the subject of considerable speculation , the biological significance of this unusual ability has until now remained unknown. We show here that warming the retina significantly improves temporal resolution, and hence the detection of rapid motion, in fast-swimming predatory fishes such as the swordfish. Depending on diving depth, temporal resolution can be more than ten times greater in these fishes than in fishes with eyes at the same temperature as the surrounding water. The enhanced temporal resolution allowed by heated eyes provides warm-blooded and highly visual oceanic predators, such as swordfishes, tunas, and sharks, with a crucial advantage over their agile, cold-blooded prey.

  16. Warm Indian Ocean, Weak Asian Monsoon

    NASA Astrophysics Data System (ADS)

    Koll Roxy, Mathew; Ritika, Kapoor; Terray, Pascal; Murtugudde, Raghu; Ashok, Karumuri; Nath Goswami, Buphendra

    2015-04-01

    There are large uncertainties looming over the status and fate of the South Asian monsoon in a changing climate. Observations and climate models have suggested that anthropogenic warming in the past century has increased the moisture availability and the land-sea thermal contrast in the tropics, favoring an increase in monsoon rainfall. In contrast, we notice that South Asian subcontinent experienced a relatively subdued warming during this period. At the same time, the tropical Indian Ocean experienced a nearly monotonic warming, at a rate faster than the other tropical oceans. Using long-term observations and coupled model experiments, we suggest that the enhanced Indian Ocean warming along with the suppressed warming of the subcontinent weaken the land-sea thermal contrast throughout the troposphere, dampen the monsoon Hadley circulation, and reduce the rainfall over South Asia. As a result, the summer monsoon rainfall during 1901-2012 shows a significant weakening trend over South Asia, extending from Pakistan through central India to Bangladesh.

  17. Pressure in electronically excited warm dense metals

    NASA Astrophysics Data System (ADS)

    Stegailov, Vladimir; Zhilyaev, Petr

    2015-06-01

    Non-equilibrium two-temperature warm dense metals consist of the ion subsystem that is subjected to structural transitions and involved in the mass transfer, and the electron subsystem that in various pulsed experiments absorbs energy and then evolves together with ions to equilibrium. Definition of pressure in such non-equilibrium systems causes certain controversy. In this work we make an attempt to clarify this definition that is vital for proper description of the whole relaxation process. Using the density functional theory we analyze on examples of Al and Au electronic pressure components in warm dense metals. Appealing to the Fermi gas model we elucidate a way to find a number of free delocalized electrons in warm dense metals. First results has been published in. This work is supported by the Russian Science Foundation grant No. 14-19-01487.

  18. The dynamics of warm and cold climates

    NASA Technical Reports Server (NTRS)

    Rind, D.

    1986-01-01

    Changes occurring as a result of climatic warming or cooling are presently investigated by comparing the atmospheric dynamics of five different climate simulations encompassing two ice ages, current and doubled CO2 climates, and a simulation of the warm Cretaceous; a global average surface air temperature range of 13 C is covered by the models. It is noted that many zonally averaged processes do not change systematically as climate changes: the January Hadley cell, the jet stream, mean precipitation patterns, and total atmospheric transport, show very little variation among the different climate simulations. These features result from balances between competing factors; while individual processes differ in the cold and warm climates, there is considerable compensation.

  19. Warm heart surgery eliminates diaphragmatic paralysis.

    PubMed

    Maccherini, M; Davoli, G; Sani, G; Rossi, P; Giani, S; Lisi, G; Mazzesi, G; Toscano, M

    1995-05-01

    Since January 1992, we adopted a new method of myocardial protection: warm blood cardioplegia with continuous ante-retrograde combined delivery during normothermic cardiopulmonary bypass, (CPB) instead of cold blood intermittent cardioplegia plus topical ice slush in hypothermic CPB. We have compared postoperative chest X-rays of 50 patients who underwent elective coronary artery bypass with normothermic CPB to postoperative chest X-rays, of 50 patients operated upon with hypothermia. In the cold group transitory diaphragmatic paralysis, as well as pleural effusions and thoracentesis related to the hypothermia, and topical cooling, were statistically increased over that of warm group. The data suggest that topical cooling with slush ice is responsible for phrenic nerve injury and that warm heart surgery has no associated incidence of diaphragmatic injury.

  20. Dynamic structure factor in warm dense beryllium

    NASA Astrophysics Data System (ADS)

    Plagemann, K.-U.; Sperling, P.; Thiele, R.; Desjarlais, M. P.; Fortmann, C.; Döppner, T.; Lee, H. J.; Glenzer, S. H.; Redmer, R.

    2012-05-01

    We calculate the dynamic structure factor (DSF) in warm dense beryllium by means of ab initio molecular dynamics simulations. The dynamic conductivity is derived from the Kubo-Greenwood formula, and a Drude-like behaviour is observed. The corresponding dielectric function is used to determine the DSF. Since the ab initio approach is so far only applicable for wavenumbers k = 0, the k-dependence of the dielectric function is modelled via the Mermin ansatz. We present the results for the dielectric function and DSF of warm dense beryllium and compare these with perturbative treatments such as the Born-Mermin approximation. We found considerable differences between the results of these approaches; this underlines the need for a first-principles determination of the DSF of warm dense matter.

  1. Warm Dirac-Born-Infeld inflation

    SciTech Connect

    Cai Yifu; Dent, James B.; Easson, Damien A.

    2011-05-15

    We propose a warm inflationary model in the context of relativistic D-brane inflation in a warped throat, which has Dirac-Born-Infeld (DBI) kinetic term and is coupled to radiation through a dissipation term. The perturbation freezes at the sound horizon and the power spectrum is determined by a combination of the dissipative parameter and the sound speed parameter. The thermal dissipation ameliorates the eta problem and softens theoretical constraints from the extra-dimensional volume and from observational bounds on the tensor-to-scalar ratio. The warm DBI model can lead to appreciable non-Gaussianity of the equilateral type. As a phenomenological model, ignoring compactification constraints, we show that large-field warm inflation models do not necessarily yield a large tensor-to-scalar ratio.

  2. Communicating the Dangers of Global Warming

    NASA Astrophysics Data System (ADS)

    Hansen, J. E.

    2006-12-01

    So far, in my opinion, we scientists have not done a good job of communicating the imminent threat posed by global warming, yet I believe there is still time for that if we work efficiently now to overcome existing obstacles. Several of those obstacles are illustrated by contrasting the roles of scientists, the media, special interests, politicians and the public in the ozone depletion and global warming crises. Scientists in America are further challenged by a decline in public science education, a perceived gap between science and religion, increasing politicization of public affairs offices in the government, and accumulation of power by a unitary executive. First order communication tasks are illustrated by a need for improved exchange and understanding, among scientists as well as with the public, of fundamental climate facts: (1) additional global warming exceeding 1C will yield large climate effects, (2) paleoclimate changes contain quantitatively specific information about climate sensitivity that is not widely appreciated, (3) carbon cycle facts, such as the substantial portion of carbon dioxide emissions that will remain in the air "forever", for practical purposes, (4) fossil fuel facts such as the dominant role of coal and unconventional fuels in all business-as-usual scenarios for future energy sources. The facts graphically illustrate the need for prompt actions to avoid disastrous climate change, yet they also reveal the feasibility of a course that minimizes global warming and yields other benefits. Perhaps the greatest challenge is posed by an inappropriate casting of the topic as a dichotomy between those who deny that there is a global warming problem and those who either are exceedingly pessimistic about the prospects for minimizing climate change or believe that solutions would be very expensive. Sensible evaluation of the situation, in my opinion, suggests a strategy for dealing with global warming that is not costly and has many subsidiary

  3. Experimental warming alters migratory caribou forage quality.

    PubMed

    Zamin, Tara J; Côté, Steeve D; Tremblay, Jean-Pierre; Grogan, Paul

    2017-10-01

    Global declines in caribou and reindeer (Rangifer) populations have drawn attention to the myriad of stressors that these Arctic and boreal forest herbivores currently face. Arctic warming has resulted in increased tundra shrub growth and therefore Rangifer forage quantity. However, its effects on forage quality have not yet been addressed although they may be critical to Rangifer body condition and fecundity. We investigated the impact of 8 yrs of summer warming on the quality of forage available to the Bathurst caribou herd using experimental greenhouses (n = 5) located in mesic birch hummock tundra in the central Canadian Low Arctic. Leaf forage quality and digestibility characteristics associated with nutrients (nitrogen and phosphorus), phenolics, and fiber were measured on the deciduous shrub Betula glandulosa (an important Rangifer diet component) at six time points through the growing season, and on five other very common vascular plant and lichen species in late summer. Experimental warming reduced B. glandulosa leaf nitrogen concentrations by ~10% in both late June and mid-July, but not afterwards. It also reduced late summer forage quality of the graminoid Eriophorum vaginatum by increasing phenolic concentrations 38%. Warming had mixed effects on forage quality of the lichen Cetraria cucullata in that it increased nutrient concentrations and tended to decrease fiber contents, but it also increased phenolics. Altogether, these warming-induced changes in forage quality over the growing season, and response differences among species, highlight the importance of Rangifer adaptability in diet selection. Furthermore, the early season reduction in B. glandulosa nitrogen content is a particular concern given the importance of this time for calf growth. Overall, our demonstration of the potential for significant warming impacts on forage quality at critical times for these animals underscores the importance of effective Rangifer range conservation to ensure

  4. Vertical structure of recent Arctic warming.

    PubMed

    Graversen, Rune G; Mauritsen, Thorsten; Tjernström, Michael; Källén, Erland; Svensson, Gunilla

    2008-01-03

    Near-surface warming in the Arctic has been almost twice as large as the global average over recent decades-a phenomenon that is known as the 'Arctic amplification'. The underlying causes of this temperature amplification remain uncertain. The reduction in snow and ice cover that has occurred over recent decades may have played a role. Climate model experiments indicate that when global temperature rises, Arctic snow and ice cover retreats, causing excessive polar warming. Reduction of the snow and ice cover causes albedo changes, and increased refreezing of sea ice during the cold season and decreases in sea-ice thickness both increase heat flux from the ocean to the atmosphere. Changes in oceanic and atmospheric circulation, as well as cloud cover, have also been proposed to cause Arctic temperature amplification. Here we examine the vertical structure of temperature change in the Arctic during the late twentieth century using reanalysis data. We find evidence for temperature amplification well above the surface. Snow and ice feedbacks cannot be the main cause of the warming aloft during the greater part of the year, because these feedbacks are expected to primarily affect temperatures in the lowermost part of the atmosphere, resulting in a pattern of warming that we only observe in spring. A significant proportion of the observed temperature amplification must therefore be explained by mechanisms that induce warming above the lowermost part of the atmosphere. We regress the Arctic temperature field on the atmospheric energy transport into the Arctic and find that, in the summer half-year, a significant proportion of the vertical structure of warming can be explained by changes in this variable. We conclude that changes in atmospheric heat transport may be an important cause of the recent Arctic temperature amplification.

  5. Thyroid storm and warm autoimmune hemolytic anemia.

    PubMed

    Moore, Joseph A; Gliga, Louise; Nagalla, Srikanth

    2017-08-18

    Graves' disease is often associated with other autoimmune disorders, including rare associations with autoimmune hemolytic anemia (AIHA). We describe a unique presentation of thyroid storm and warm AIHA diagnosed concurrently in a young female with hyperthyroidism. The patient presented with nausea, vomiting, diarrhea and altered mental status. Laboratory studies revealed hemoglobin 3.9g/dL, platelets 171×10(9)L(-1), haptoglobin <5mg/dL, reticulocytosis, and positive direct antiglobulin test (IgG, C3d, warm). Additional workup revealed serum thyroid stimulating hormone (TSH) <0.01μIU/mL and serum free-T4 (FT4) level 7.8ng/dL. Our patient was diagnosed with concurrent thyroid storm and warm AIHA. She was started on glucocorticoids to treat both warm AIHA and thyroid storm, as well as antithyroid medications, propranolol and folic acid. Due to profound anemia and hemodynamic instability, the patient was transfused two units of uncrossmatched packed red blood cells slowly and tolerated this well. She was discharged on methimazole as well as a prolonged prednisone taper, and achieved complete resolution of the thyrotoxicosis and anemia at one month. Hyperthyroidism can affect all three blood cell lineages of the hematopoietic system. Anemia can be seen in 10-20% of patients with thyrotoxicosis. Several autoimmune processes can lead to anemia in Graves' disease, including pernicious anemia, celiac disease, and warm AIHA. This case illustrates a rarely described presentation of a patient with Graves' disease presenting with concurrent thyroid storm and warm AIHA. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Timing the warm absorber in NGC 4051

    NASA Astrophysics Data System (ADS)

    Silva, C. V.; Uttley, P.; Costantini, E.

    2016-12-01

    We investigated, using spectral-timing analysis, the characterization of highly ionized outflows in Seyfert galaxies, the so-called warm absorbers. Here, we present our results of the extensive 600 ks of XMM-Newton archival observations of the bright and highly variable Seyfert 1 galaxy NGC 4051 whose spectrum has revealed a complex multicomponent wind. Making use of both RGS and EPIC-pn data, we performed a detailed analysis through a time-dependent photoionization code in combination with spectral and Fourier spectral-timing techniques. The source light curves and the warm absorber parameters obtained from the data were used to simulate the response of the gas to variations in the ionizing flux of the central source. The resulting time variable spectra were employed to predict the effects of the warm absorber on the time lags and coherence of the energy dependent light curves. We have found that, in the absence of any other lag mechanisms, a warm absorber with the characteristics of the one observed in NGC 4051, is able to produce soft lags, up to 100 s, on timescales of hours. The time delay is associated with the response of the gas to changes in the ionizing source, either by photoionization or radiative recombination, which is dependent on its density. The range of radial distances that, under our assumptions, yield longer time delays are distances r 0.3-1.0 × 1016 cm, and hence gas densities n 0.4-3.0 × 107 cm-3. Since these ranges are comparable to the existing estimates of the location of the warm absorber in NGC 4051, we suggest that it is likely that the observed X-ray time lags may carry a signature of the warm absorber response time to changes in the ionizing continuum. Our results show that the warm absorber in NGC 4051 does not introduce lags on the short timescales associated with reverberation, but will likely modify the hard continuum lags seen on longer timescales, which in this source have been measured to be on the order of 50 s. Hence, these

  7. Global warming: a public health concern.

    PubMed

    Afzal, Brenda M

    2007-05-31

    Over the last 100 years the average temperature on the Earth has risen approximately 1ºFahrenheit (F), increasing at a rate twice as fast as has been noted for any period in the last 1,000 years. The Arctic ice cap is shrinking, glaciers are melting, and the Arctic permafrost is thawing. There is mounting evidence that these global climate changes are already affecting human health. This article provides a brief overview of global warming and climate changes, discusses effects of climate change on health, considers the factors which contribute to climate changes, and reviews individual and collective efforts related to reducing global warming.

  8. Winter warming from large volcanic eruptions

    NASA Technical Reports Server (NTRS)

    Robock, Alan; Mao, Jianping

    1992-01-01

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

  9. Analysis of data from spacecraft (stratospheric warmings)

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Investigations involved a search through existing literature and data to obtain case histories for the six or more stratospheric warmings that occurred in April - May 1969, June - July 1969, August 1969, December 1969 - January 1970, December 1970 - January 1971, and January 1973 - February 1973. For each of these warmings the following steps have been taken in preparation for analysis: (1) defining the nature of the problem; (2) literature search of stratwarmings and solar-terrestrial phenomens; and (3) file of data sources, especially stratospheric temperatures (radiances) and geophysical indices.

  10. Global warming and sexual plant reproduction.

    PubMed

    Hedhly, Afif; Hormaza, José I; Herrero, María

    2009-01-01

    The sexual reproductive phase in plants might be particularly vulnerable to the effects of global warming. The direct effect of temperature changes on the reproductive process has been documented previously, and recent data from other physiological processes that are affected by rising temperatures seem to reinforce the susceptibility of the reproductive process to a changing climate. But the reproductive phase also provides the plant with an opportunity to adapt to environmental changes. Understanding phenotypic plasticity and gametophyte selection for prevailing temperatures, along with possible epigenetic changes during this process, could provide new insights into plant evolution under a global-warming scenario.

  11. Dynamic characteristics of observed sudden warmings

    NASA Technical Reports Server (NTRS)

    Dartt, D. G.; Venne, D. E.

    1986-01-01

    The planetary wave dynamics of stratospheric sudden warmings in the Northern Hemisphere for a large number of observed events that occurred during winters from 1970 to 1975 and 1978 to 1981 are investigated. The analysis describes wave propagation and zonal flow interaction from the troposphere upwards to near 50 km, and in some years to near 80 km. Three primary topics are covered here: (1) the interaction of zonally propagating and quasi-stationary planetary waves during warming events; (2) planetary wave influence on zonal flow near the stratopause; and (3) planetary wave propagation to near 80 km as seen from Stratospheric and Mesospheric Sounder (SAMS) data.

  12. Is the climate warming or cooling?

    NASA Astrophysics Data System (ADS)

    Easterling, David R.; Wehner, Michael F.

    2009-04-01

    Numerous websites, blogs and articles in the media have claimed that the climate is no longer warming, and is now cooling. Here we show that periods of no trend or even cooling of the globally averaged surface air temperature are found in the last 34 years of the observed record, and in climate model simulations of the 20th and 21st century forced with increasing greenhouse gases. We show that the climate over the 21st century can and likely will produce periods of a decade or two where the globally averaged surface air temperature shows no trend or even slight cooling in the presence of longer-term warming.

  13. Winter warming from large volcanic eruptions

    SciTech Connect

    Robock, A.; Mao, J.

    1992-01-01

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

  14. Winter warming from large volcanic eruptions

    NASA Technical Reports Server (NTRS)

    Robock, Alan; Mao, Jianping

    1992-01-01

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

  15. National Update: Discussions on global warming

    SciTech Connect

    Not Available

    1989-04-01

    The American Forestry Association (AFA) has launched a national campaign called Global Releaf to educate the public about global warming and the role of forestry in alleviating its effects. AFA executive vice-president R. Neil Sampson states that trees need to be intentionally grown and managed. More trees means less CO{sub 2} buildup, and the lack of trees is one of the causes of global warming. The AFA campaign included public service announcements, educational posters for schools, and material for all forms of media.

  16. Climate change lessons from a warm world

    USGS Publications Warehouse

    Dowsett, Harry J.

    2010-01-01

    In the early 1970’s to early 1980’s Soviet climatologists were making comparisons to past intervals of warmth in the geologic record and suggesting that these intervals could be possible analogs for 21st century “greenhouse” conditions. Some saw regional warming as a benefit to the Soviet Union and made comments along the lines of “Set fire to the coal mines!” These sentiments were alarming to some, and the United States Geological Survey (USGS) leadership thought they could provide a more quantitative analysis of the data the Soviets were using for the most recent of these warm intervals, the Early Pliocene.

  17. Even warm climates get the shivers

    SciTech Connect

    Kerr, R.A.

    1993-07-16

    Researchers in the Greenland Ice-Core Project (GRIP) have found evidence of sharp climate shifts during the last two intergalcials. The Greenland ice sheet evidence shows that Greenland, over and over for decades to thousands of years, cooled drastically from temperatures equal to or higher than today's, often to virtual ice age conditions. The researchers believe that disruptions in the flow of warm water from the southern Atlantic to the North Atlantic, and the return flow of cold water to the south, may be linked to these climatic fluctuations. The present climate appears relatively stable, but that may change if temperatures warm due to increases in atmospheric greenhouse gases.

  18. The recent warming trend in North Greenland

    NASA Astrophysics Data System (ADS)

    Orsi, Anais; Kawamura, Kenji; Masson-Delmotte, Valerie; Landais, Amaelle; Severinghaus, Jeff

    2015-04-01

    The arctic is the fastest warming region on Earth, but it is also one where there is little historical data. Although summer warming causes melt, the annual temperature trend is dominated by the winter and fall season, which are much less well documented. In addition, the instrumental record relies principally on coastal weather stations, and there are very few direct temperature observations in the interior dating back more than 30 years, especially in North Greenland, where the current warming trend is the largest. Here, we present a temperature reconstruction from NEEM (51°W, 77°N), in North Greenland, for the last 100 years, which allows us to put the recent trend in the context of the longer term climate. We use a combination of two independent proxies to reconstruct the temperature history at NEEM: borehole temperature and inert gas isotope measurements in the firn. Borehole temperature takes advantage of the low temperature diffusivity of the snow and ice, which allows the temperature history to be preserved in the ice for several centuries. Temperature gradients in the firn (old snow above the ice) influence the gas isotopic composition: thermal fractionation causes heavy isotopes to concentrate on the cold end of the firn column. We measured the isotopes of inert gases (N2, Ar and Kr), which have a constant atmospheric composition through time, and use the thermal fractionation signal as an additional constraint on the temperature history at the site. We find that NEEM has been warming by 0.86±0.22°C/decade over the past 30 years, from -28.55±0.29°C for the 1900-1970 average to -26.77±0.16°C for the 2000-2010 average. The warming rate at NEEM is similar to that of Greenland Summit, and confirms the large warming trends in North Greenland (polar amplification) and high altitude sites (tropospheric rather than surface warming). Water isotopes show that the recent past has not met the level of the 1928 anomaly; but the average of the past 30 years has

  19. Global warming -- Science and anti-science

    SciTech Connect

    Preining, O. |

    1995-06-01

    The global warming debate has sparked many facts activities in almost all sectors of human endeavors. There are the hard facts, the measurements of the greenhouse gases, the statistics of human activities responsible for emissions, the demographic figures. There are the soft facts, the interpretations of the hard facts requiring additional assumptions. There are the media, the press, television, for whom environmental problems make good stories, these can be used to rise emotions, to make heroes and antiheroes. There are politicians, the global warming debate can be used even in electron campaigns. Global warming is a topic within and beyond science. The judgment (and hence use) of scientific facts is overwhelmingly influenced by the ``Weltbild`` (underlying beliefs how the world operates), and consequently opposing positions of well-known scientists arise. There are the attempts to invent futures of man on Earth: policies, regulations, laws on nation, international, and global levels shall facilitate a change in the basic behavior of all men. The global warming issue has many facets and cannot be successfully discussed without including, e.g., the North-South dialogue, world population, etc.

  20. The recent warming trend in North Greenland

    NASA Astrophysics Data System (ADS)

    Orsi, Anais J.; Kawamura, Kenji; Masson-Delmotte, Valerie; Fettweis, Xavier; Box, Jason E.; Dahl-Jensen, Dorthe; Clow, Gary D.; Landais, Amaelle; Severinghaus, Jeffrey P.

    2017-06-01

    The Arctic is among the fastest warming regions on Earth, but it is also one with limited spatial coverage of multidecadal instrumental surface air temperature measurements. Consequently, atmospheric reanalyses are relatively unconstrained in this region, resulting in a large spread of estimated 30 year recent warming trends, which limits their use to investigate the mechanisms responsible for this trend. Here we present a surface temperature reconstruction over 1982-2011 at NEEM (North Greenland Eemian Ice Drilling Project, 51°W, 77°N), in North Greenland, based on the inversion of borehole temperature and inert gas isotope data. We find that NEEM has warmed by 2.7 ± 0.33°C over the past 30 years, from the long-term 1900-1970 average of -28.55 ± 0.29°C. The warming trend is principally caused by an increase in downward longwave heat flux. Atmospheric reanalyses underestimate this trend by 17%, underlining the need for more in situ observations to validate reanalyses.

  1. Temperature Data Shows Warming in 2001

    NASA Technical Reports Server (NTRS)

    2002-01-01

    TThe figure above depicts how much air temperatures near the Earth's surface changed relative to the global mean temperature from 1951 to 1980. NASA researchers used maps of urban areas derived from city lights data to account for the 'heat island' effect of cities. The red and orange colors show that temperatures are warmer in most regions of the world when compared to the 1951 to 1980 'normal' temperatures. Warming around the world has been widespread, but it is not present everywhere. The largest warming is in Northern Canada, Alaska and Siberia, as indicated by the deeper red colors. The lower 48 United States have become warmer recently, but only enough to make the temperatures comparable to what they were in the 1930s. The scale on the bottom of these temperature anomaly images represent degrees in Celsius. The negative numbers represent cooling and the positive numbers depict warming. Overall, the air temperature near the Earth's surface has warmed by 1oF (0.6oC) globally, on average, over the last century. For more information and additional images, read Satellites Shed Light on a Warmer World. Image courtesy Goddard Institute for Space Studies (GISS).

  2. Arctic decadal variability in a warming world

    NASA Astrophysics Data System (ADS)

    van der Linden, Eveline C.; Bintanja, Richard; Hazeleger, Wilco

    2017-06-01

    Natural decadal variability of surface air temperature might obscure Arctic temperature trends induced by anthropogenic forcing. It is therefore imperative to know how Arctic decadal variability (ADV) will change as the climate warms. In this study, we evaluate ADV characteristics in three equilibrium climates with present-day, double, and quadrupled atmospheric CO2 forcing. The dominant region of variability, which is located over the Barents and Greenland Sea at present, shifts to the central Arctic and Siberian regions as the climate warms. The maximum variability in sea ice cover and surface air temperature occurs in the CO2 doubling climate when sea ice becomes more vulnerable to melt over vast stretches of the Arctic. Furthermore, the links between dominant atmospheric circulation modes and Arctic surface climate characteristics vary strongly with climate change. For instance, a positive Arctic Oscillation index is associated with a colder Arctic in warmer climates, instead of a warmer Arctic at present. Such changing relationships are partly related to the retreat of sea ice because altered wind patterns influence the sea ice distribution and hence the associated local surface fluxes. The atmospheric pressure distributions governing ADV and the associated large-scale dynamics also change with climate warming. The changing character of the ADV shows that it is vital to consider (changes in) ADV when addressing Arctic warming in climate model projections.

  3. Humid heat waves at different warming levels.

    PubMed

    Russo, Simone; Sillmann, Jana; Sterl, Andreas

    2017-08-07

    The co-occurrence of consecutive hot and humid days during a heat wave can strongly affect human health. Here, we quantify humid heat wave hazard in the recent past and at different levels of global warming. We find that the magnitude and apparent temperature peak of heat waves, such as the ones observed in Chicago in 1995 and China in 2003, have been strongly amplified by humidity. Climate model projections suggest that the percentage of area where heat wave magnitude and peak are amplified by humidity increases with increasing warming levels. Considering the effect of humidity at 1.5° and 2° global warming, highly populated regions, such as the Eastern US and China, could experience heat waves with magnitude greater than the one in Russia in 2010 (the most severe of the present era). The apparent temperature peak during such humid-heat waves can be greater than 55 °C. According to the US Weather Service, at this temperature humans are very likely to suffer from heat strokes. Humid-heat waves with these conditions were never exceeded in the present climate, but are expected to occur every other year at 4° global warming. This calls for respective adaptation measures in some key regions of the world along with international climate change mitigation efforts.

  4. Temperature Data Shows Warming in 2001

    NASA Technical Reports Server (NTRS)

    2002-01-01

    TThe figure above depicts how much air temperatures near the Earth's surface changed relative to the global mean temperature from 1951 to 1980. NASA researchers used maps of urban areas derived from city lights data to account for the 'heat island' effect of cities. The red and orange colors show that temperatures are warmer in most regions of the world when compared to the 1951 to 1980 'normal' temperatures. Warming around the world has been widespread, but it is not present everywhere. The largest warming is in Northern Canada, Alaska and Siberia, as indicated by the deeper red colors. The lower 48 United States have become warmer recently, but only enough to make the temperatures comparable to what they were in the 1930s. The scale on the bottom of these temperature anomaly images represent degrees in Celsius. The negative numbers represent cooling and the positive numbers depict warming. Overall, the air temperature near the Earth's surface has warmed by 1oF (0.6oC) globally, on average, over the last century. For more information and additional images, read Satellites Shed Light on a Warmer World. Image courtesy Goddard Institute for Space Studies (GISS).

  5. Abrupt warming of the Red Sea

    NASA Astrophysics Data System (ADS)

    Raitsos, D. E.; Hoteit, I.; Prihartato, P. K.; Chronis, T.; Triantafyllou, G.; Abualnaja, Y.

    2011-07-01

    Coral reef ecosystems, often referred to as “marine rainforests,” concentrate the most diverse life in the oceans. Red Sea reef dwellers are adapted in a very warm environment, fact that makes them vulnerable to further and rapid warming. The detection and understanding of abrupt temperature changes is an important task, as ecosystems have more chances to adapt in a slowly rather than in a rapid changing environment. Using satellite derived sea surface and ground based air temperatures, it is shown that the Red Sea is going through an intense warming initiated in the mid-90s, with evidence for an abrupt increase after 1994 (0.7°C difference pre and post the shift). The air temperature is found to be a key parameter that influences the Red Sea marine temperature. The comparisons with Northern Hemisphere temperatures revealed that the observed warming is part of global climate change trends. The hitherto results also raise additional questions regarding other broader climatic impacts over the area.

  6. Can Global Warming Heat Up Environmental Education?

    ERIC Educational Resources Information Center

    Mazzatenta, Claudio

    2008-01-01

    Bronx Community College (CUNY) launched "Global Warming Campus Awareness and Action Days" in celebration of Earth Day, 2007. The purpose of this program was to raise awareness of environmental issues in the college population, especially students. To let more students have a grasp of what Environmental Education (EE) is all about, the author…

  7. Warm Hydroforming of Lightweight Metal Sheets

    SciTech Connect

    Aginagalde, A.; Orus, A.; Esnaola, J. A.; Torca, I.; Galdos, L.; Garcia, C.

    2007-05-17

    Hydroforming is well known in steel applications for automotive industry, where complicated shapes can be get with high strength to weight ratios. Nevertheless, the poor formability of light alloys at room temperature has limited the application of hydroforming technology for aluminum and magnesium parts. Increasing the temperature of these materials allows substantially greater elongation without fracture. Warm forming strategy is applied in conventional processes, such as rolling and forging, in order to get complex shapes, but still rare in hydroforming technology. This is the technical base of this research project: the development of the hydroforming process at warm working temperatures. The main tasks of the initial phases of the research were the material characterization, and the heated fluid and tooling system design and set up for warm hydroforming of lightweight alloys. Once these goals were accomplished the present paper shows the obtained results. The uniaxial tensile deformation of 5754H111, 6082-T6, 6082-O and AZ31B at the temperature range of 25 deg. C - 250 deg. C is presented as the output of the material characterization task. Both the system features and the results obtained for a bulge test geometry carried out with a warm hydroforming system are also presented. The selected alloys show an improvement in formability at the studied temperature range under both uniaxial and biaxial state of stress.

  8. The global warming hiatus: Slowdown or redistribution?

    NASA Astrophysics Data System (ADS)

    Yan, Xiao-Hai; Boyer, Tim; Trenberth, Kevin; Karl, Thomas R.; Xie, Shang-Ping; Nieves, Veronica; Tung, Ka-Kit; Roemmich, Dean

    2016-11-01

    Global mean surface temperatures (GMST) exhibited a smaller rate of warming during 1998-2013, compared to the warming in the latter half of the 20th Century. Although, not a "true" hiatus in the strict definition of the word, this has been termed the "global warming hiatus" by IPCC (2013). There have been other periods that have also been defined as the "hiatus" depending on the analysis. There are a number of uncertainties and knowledge gaps regarding the "hiatus." This report reviews these issues and also posits insights from a collective set of diverse information that helps us understand what we do and do not know. One salient insight is that the GMST phenomenon is a surface characteristic that does not represent a slowdown in warming of the climate system but rather is an energy redistribution within the oceans. Improved understanding of the ocean distribution and redistribution of heat will help better monitor Earth's energy budget and its consequences. A review of recent scientific publications on the "hiatus" shows the difficulty and complexities in pinpointing the oceanic sink of the "missing heat" from the atmosphere and the upper layer of the oceans, which defines the "hiatus." Advances in "hiatus" research and outlooks (recommendations) are given in this report.

  9. Global Warming 'Pause' - Oceans Reshuffle Heat

    NASA Astrophysics Data System (ADS)

    Nieves, V.; Willis, J. K.; Patzert, W. C.

    2015-12-01

    Despite the fact that greenhouse gases are still increasing and all other indicators show warming-related change (+0.0064 °C/year since 1880 or +0.0077 °C/year during 1993-2002), surface temperatures stopped climbing steadily during the past decade at a rate of +0.0010 °C/year from 2003 to 2012. We show that in recent years, the heat was being trapped in the subsurface waters of the western Pacific and eastern Indian oceans between 100 and 300 m. The movement of warm Pacific water below the surface, also related to the Pacific Decadal Oscillation climatic pattern, temporarily affected surface temperatures and accounted for the global cooling trend in surface temperature. With the Pacific Decadal Oscillation possibly changing to a warm phase, it is likely that the oceans will drive a major surge in global surface warming sometime in the next decade or two. Reference: Nieves, V., Willis, J. K., and Patzert, W. C. (2015). Recent hiatus caused by decadal shift in Indo-Pacific heating. Science, aaa4521.

  10. Global warming and extreme storm surges

    NASA Astrophysics Data System (ADS)

    Grinsted, Aslak

    2013-04-01

    I will show empirical evidence for how global warming has changed extreme storm surge statistics for different regions in the world. Are there any detectable changes beyond what we expect from sea level rise. What does this suggest about the future of hurricane surges such as from hurricane Katrina and superstorm Sandy?

  11. Desert Amplification in a Warming Climate

    NASA Astrophysics Data System (ADS)

    Zhou, Liming

    2016-08-01

    Here I analyze the observed and projected surface temperature anomalies over land between 50°S-50°N for the period 1950–2099 by large-scale ecoregion and find strongest warming consistently and persistently seen over driest ecoregions such as the Sahara desert and the Arabian Peninsula during various 30-year periods, pointing to desert amplification in a warming climate. This amplification enhances linearly with the global mean greenhouse gases(GHGs) radiative forcing and is attributable primarily to a stronger GHGs-enhanced downward longwave radiation forcing reaching the surface over drier ecoregions as a consequence of a warmer and thus moister atmosphere in response to increasing GHGs. These results indicate that desert amplification may represent a fundamental pattern of global warming associated with water vapor feedbacks over land in low- and mid- latitudes where surface warming rates depend inversely on ecosystem dryness. It is likely that desert amplification might involve two types of water vapor feedbacks that maximize respectively in the tropical upper troposphere and near the surface over deserts, with both being very dry and thus extremely sensitive to changes of water vapor.

  12. National contributions to observed global warming

    NASA Astrophysics Data System (ADS)

    Damon Matthews, H.; Graham, Tanya L.; Keverian, Serge; Lamontagne, Cassandra; Seto, Donny; Smith, Trevor J.

    2014-01-01

    There is considerable interest in identifying national contributions to global warming as a way of allocating historical responsibility for observed climate change. This task is made difficult by uncertainty associated with national estimates of historical emissions, as well as by difficulty in estimating the climate response to emissions of gases with widely varying atmospheric lifetimes. Here, we present a new estimate of national contributions to observed climate warming, including CO2 emissions from fossil fuels and land-use change, as well as methane, nitrous oxide and sulfate aerosol emissions While some countries’ warming contributions are reasonably well defined by fossil fuel CO2 emissions, many countries have dominant contributions from land-use CO2 and non-CO2 greenhouse gas emissions, emphasizing the importance of both deforestation and agriculture as components of a country’s contribution to climate warming. Furthermore, because of their short atmospheric lifetime, recent sulfate aerosol emissions have a large impact on a country’s current climate contribution We show also that there are vast disparities in both total and per-capita climate contributions among countries, and that across most developed countries, per-capita contributions are not currently consistent with attempts to restrict global temperature change to less than 2 °C above pre-industrial temperatures.

  13. Is Europa's Subsurface Water Ocean Warm?

    NASA Technical Reports Server (NTRS)

    Melosh, H. J.; Ekholm, A. G.; Showman, A. P.; Lorenz, R. D.

    2002-01-01

    Europa's subsurface water ocean may be warm: that is, at the temperature of water's maximum density. This provides a natural explanation of chaos melt-through events and leads to a correct estimate of the age of its surface. Additional information is contained in the original extended abstract.

  14. Warm reactive autoantibodies: clinical and serologic correlations.

    PubMed

    Wheeler, Christine A; Calhoun, Loni; Blackall, Douglas P

    2004-11-01

    Warm reactive autoantibodies are encountered relatively frequently in tertiary care hospitals. We studied 100 consecutive patients with warm autoantibodies to correlate their clinical and serologic features. Study patients (56 male, 44 female) had various diagnoses and a mean age of 53.5 years (range, 3-90 years). Autoimmune hemolysis was documented in 29 patients; 20 patients (69%) in this subset had diseases classically associated with warm autoimmune hemolytic anemia (hematologic and autoimmune disorders). All study patients demonstrated IgG on their RBCs (direct antiglobulin test [DAT] reactivity range, microscopic to 4+); 49 also demonstrated C3 (reactivity range, microscopic to 3+). The DAT for IgG was 2+ or more in 25 (86%) of 29 patients with hemolysis; the DAT for IgG was 1+ or less in 45 (63%) of 71 patients without hemolysis. In patients with hemolysis, 21 (72%) of 29 had a DAT reactive for C3. These findings may be useful in determining the clinical significance of warm autoantibodies and the extent to which patients should be followed up for hemolysis.

  15. Global warming and health: a review.

    PubMed

    Amofah, G K

    1996-08-01

    The paper looks at the phenomenon of global warming and its potential health effects and outlines a number of plausible response by the health sector in developing countries to its threat. It suggests that the health sector should facilitate an international effort at addressing this challenge, mainly through advocacy, epidemiological surveillance and awareness creation.

  16. Global Warming, A Tragedy of the Commons

    NASA Astrophysics Data System (ADS)

    Philander, S. G.

    2016-12-01

    What is the appropriate balance between our responsibilities towards future generations, and our obligations to those who live in abject poverty today? Global warming, a tragedy of the commons, brings such ethical questions to the fore but, whether "matured" or not, is itself mute on ethical issues.

  17. Microclimate moderates plant responses to macroclimate warming.

    PubMed

    De Frenne, Pieter; Rodríguez-Sánchez, Francisco; Coomes, David Anthony; Baeten, Lander; Verstraeten, Gorik; Vellend, Mark; Bernhardt-Römermann, Markus; Brown, Carissa D; Brunet, Jörg; Cornelis, Johnny; Decocq, Guillaume M; Dierschke, Hartmut; Eriksson, Ove; Gilliam, Frank S; Hédl, Radim; Heinken, Thilo; Hermy, Martin; Hommel, Patrick; Jenkins, Michael A; Kelly, Daniel L; Kirby, Keith J; Mitchell, Fraser J G; Naaf, Tobias; Newman, Miles; Peterken, George; Petrík, Petr; Schultz, Jan; Sonnier, Grégory; Van Calster, Hans; Waller, Donald M; Walther, Gian-Reto; White, Peter S; Woods, Kerry D; Wulf, Monika; Graae, Bente Jessen; Verheyen, Kris

    2013-11-12

    Recent global warming is acting across marine, freshwater, and terrestrial ecosystems to favor species adapted to warmer conditions and/or reduce the abundance of cold-adapted organisms (i.e., "thermophilization" of communities). Lack of community responses to increased temperature, however, has also been reported for several taxa and regions, suggesting that "climatic lags" may be frequent. Here we show that microclimatic effects brought about by forest canopy closure can buffer biotic responses to macroclimate warming, thus explaining an apparent climatic lag. Using data from 1,409 vegetation plots in European and North American temperate forests, each surveyed at least twice over an interval of 12-67 y, we document significant thermophilization of ground-layer plant communities. These changes reflect concurrent declines in species adapted to cooler conditions and increases in species adapted to warmer conditions. However, thermophilization, particularly the increase of warm-adapted species, is attenuated in forests whose canopies have become denser, probably reflecting cooler growing-season ground temperatures via increased shading. As standing stocks of trees have increased in many temperate forests in recent decades, local microclimatic effects may commonly be moderating the impacts of macroclimate warming on forest understories. Conversely, increases in harvesting woody biomass--e.g., for bioenergy--may open forest canopies and accelerate thermophilization of temperate forest biodiversity.

  18. Microclimate moderates plant responses to macroclimate warming

    PubMed Central

    De Frenne, Pieter; Rodríguez-Sánchez, Francisco; Coomes, David Anthony; Baeten, Lander; Verstraeten, Gorik; Vellend, Mark; Bernhardt-Römermann, Markus; Brown, Carissa D.; Brunet, Jörg; Cornelis, Johnny; Decocq, Guillaume M.; Dierschke, Hartmut; Eriksson, Ove; Gilliam, Frank S.; Hédl, Radim; Heinken, Thilo; Hermy, Martin; Hommel, Patrick; Jenkins, Michael A.; Kelly, Daniel L.; Kirby, Keith J.; Mitchell, Fraser J. G.; Naaf, Tobias; Newman, Miles; Peterken, George; Petřík, Petr; Schultz, Jan; Sonnier, Grégory; Van Calster, Hans; Waller, Donald M.; Walther, Gian-Reto; White, Peter S.; Woods, Kerry D.; Wulf, Monika; Graae, Bente Jessen; Verheyen, Kris

    2013-01-01

    Recent global warming is acting across marine, freshwater, and terrestrial ecosystems to favor species adapted to warmer conditions and/or reduce the abundance of cold-adapted organisms (i.e., “thermophilization” of communities). Lack of community responses to increased temperature, however, has also been reported for several taxa and regions, suggesting that “climatic lags” may be frequent. Here we show that microclimatic effects brought about by forest canopy closure can buffer biotic responses to macroclimate warming, thus explaining an apparent climatic lag. Using data from 1,409 vegetation plots in European and North American temperate forests, each surveyed at least twice over an interval of 12–67 y, we document significant thermophilization of ground-layer plant communities. These changes reflect concurrent declines in species adapted to cooler conditions and increases in species adapted to warmer conditions. However, thermophilization, particularly the increase of warm-adapted species, is attenuated in forests whose canopies have become denser, probably reflecting cooler growing-season ground temperatures via increased shading. As standing stocks of trees have increased in many temperate forests in recent decades, local microclimatic effects may commonly be moderating the impacts of macroclimate warming on forest understories. Conversely, increases in harvesting woody biomass—e.g., for bioenergy—may open forest canopies and accelerate thermophilization of temperate forest biodiversity. PMID:24167287

  19. Carbonyl sulfide: No remedy for global warming

    NASA Astrophysics Data System (ADS)

    Taubman, Steven J.; Kasting, James F.

    1995-04-01

    The enhancement of the stratospheric aerosol layer caused by the eruption of Mt. Pinatubo (June 15, 1991), and the subsequent cooling of the earth's lower atmosphere [Dutton and Christy, 1992; Minnis et al., 1993] shows that stratospheric aerosols can have a strong effect on the earth's climate. This supports the notion that the intentional enhancement of the stratospheric aerosol layer through increased carbonyl sulfide (OCS) emissions might be an effective means for counteracting global warming. Through the use of a one-dimensional photochemical model, we investigate what effect such a program might have on global average stratospheric ozone. In addition, we consider the impact of enhanced OCS emissions on rainwater acidity and on the overall health of both plants and animals. We find that while the warming produced by a single CO2 doubling (1 to 4°C) might be offset with ozone losses of less than 5%, any attempt to use carbonyl sulfide as a permanent solution to global warming could result in depletion of global average ozone by 30% or more. We estimate that in order to achieve cooling of 4°C rainwater pH would fall to between 3.5 and 3.8. Finally, a 4°C cooling at the surface will require that ambient near ground OCS levels rise to above 10 ppmv which is probably greater than the safe exposure limit for humans. Thus, enhanced OCS emissions do not provide an environmentally acceptable solution to the problem of global warming.

  20. Should Patients With Haemorrhage Be Kept Warm?

    DTIC Science & Technology

    2010-01-01

    and upward shift of the Starling relationship by way of a compensatory sympathetic excitation ( Braunwald et al. 1967). The resultant increase in...to volume status should be mandated in re-warming protocols. References Braunwald E, Ross J Jr & Sonnenblick EH (1967). N Engl J Med 277, 794–800

  1. Desert Amplification in a Warming Climate

    PubMed Central

    Zhou, Liming

    2016-01-01

    Here I analyze the observed and projected surface temperature anomalies over land between 50°S-50°N for the period 1950–2099 by large-scale ecoregion and find strongest warming consistently and persistently seen over driest ecoregions such as the Sahara desert and the Arabian Peninsula during various 30-year periods, pointing to desert amplification in a warming climate. This amplification enhances linearly with the global mean greenhouse gases(GHGs) radiative forcing and is attributable primarily to a stronger GHGs-enhanced downward longwave radiation forcing reaching the surface over drier ecoregions as a consequence of a warmer and thus moister atmosphere in response to increasing GHGs. These results indicate that desert amplification may represent a fundamental pattern of global warming associated with water vapor feedbacks over land in low- and mid- latitudes where surface warming rates depend inversely on ecosystem dryness. It is likely that desert amplification might involve two types of water vapor feedbacks that maximize respectively in the tropical upper troposphere and near the surface over deserts, with both being very dry and thus extremely sensitive to changes of water vapor. PMID:27538725

  2. Can we delay a greenhouse warming

    SciTech Connect

    Perry, A.M.

    1983-01-01

    The author comments on the EPA report dated September 1983 Can We Delay A Greenhouse Warming. He takes exception to the widely-held interpretation that the answer is not much. The contribution of other greenhouse gases such as methane and nitrous oxide to the EPA scenarios is pointed out, and the lack of understanding of their role is emphasised. (ACR)

  3. Pronounced Warming of the Greenland Ice Sheet

    NASA Astrophysics Data System (ADS)

    Polashenski, C.; Courville, Z.; Benson, C. S.; Wong, G. J.; Hawley, R. L.; Hall, D. K.; Chen, J.

    2013-12-01

    In the late spring and early summer of 2013, researchers on the SAGE (Sunlight Absorption on the Greenland ice sheet Experiment) Traverse, conducted a 4000 km snowmobile traverse across northwest Greenland. One aspect of this study collected field measurements of borehole temperatures across the northern Greenland ice sheet. Sites first measured by Benson in 1953-1955 are re-visited, showing long term trends in ice sheet temperature. Results indicate a pattern of dramatic warming (up to +5-6 C) at mid-level elevations (1400-2500 m) and little temperature change or perhaps slight cooling at high elevations (>2500 m). Compared to coastal West Greenland stations and Arctic-wide temperature reconstructions, which indicate warming trends of 1-1.5 C over the intervening 58-60 years, both results are surprising. Several mechanisms are explored which may account for the rapid warming of mid-altitude ice sheet, including albedo changes and elevated heat transport into the ice due to percolation. The observed ice warming, increasing ice temperature faster than air temperature changes, has serious implications, potentially driving melt facies up the ice sheet faster than would otherwise be expected and priming the ice sheet for greater runoff production.

  4. Global Warming without Global Mean Precipitation Increase?

    NASA Astrophysics Data System (ADS)

    Salzmann, Marc

    2017-04-01

    Global climate models simulate a robust increase of global mean precipitation of about 1.5 to 2% per kelvin surface warming in response to greenhouse gas (GHG) forcing. Here, it is shown the sensitivity to aerosol cooling is robust as well, albeit roughly twice as large (3-4% per kelvin). This larger sensitivity is consistent with energy budget arguments. At the same time, it is still considerably lower than the 6.5 to 7%K-1 decrease of the water vapor concentration with cooling from anthropogenic aerosol since the water vapor radiative feedback lowers the hydrological sensitivity to anthropogenic forcings. When GHG and aerosol forcings are combined, the climate models with a realistic 20th century warming indicate that the global mean hydrological response to GHG warming has until recently been completely masked by aerosol drying. This explains the apparent lack of sensitivity of the global mean precipitation to the net global warming recently found in observations. As the importance of GHGs increases in the future, a clear signal will emerge.

  5. Warm inflationary model in loop quantum cosmology

    SciTech Connect

    Herrera, Ramon

    2010-06-15

    A warm inflationary universe model in loop quantum cosmology is studied. In general we discuss the condition of inflation in this framework. By using a chaotic potential, V({phi}){proportional_to}{phi}{sup 2}, we develop a model where the dissipation coefficient {Gamma}={Gamma}{sub 0}=constant. We use recent astronomical observations for constraining the parameters appearing in our model.

  6. Can Global Warming Heat Up Environmental Education?

    ERIC Educational Resources Information Center

    Mazzatenta, Claudio

    2008-01-01

    Bronx Community College (CUNY) launched "Global Warming Campus Awareness and Action Days" in celebration of Earth Day, 2007. The purpose of this program was to raise awareness of environmental issues in the college population, especially students. To let more students have a grasp of what Environmental Education (EE) is all about, the author…

  7. Global warming in the public sphere.

    PubMed

    Corfee-Morlot, Jan; Maslin, Mark; Burgess, Jacquelin

    2007-11-15

    Although the science of global warming has been in place for several decades if not more, only in the last decade and a half has the issue moved clearly into the public sphere as a public policy issue and a political priority. To understand how and why this has occurred, it is essential to consider the history of the scientific theory of the greenhouse effect, the evidence that supports it and the mechanisms through which science interacts with lay publics and other elite actors, such as politicians, policymakers and business decision makers. This article reviews why and how climate change has moved from the bottom to the top of the international political agenda. It traces the scientific discovery of global warming, political and institutional developments to manage it as well as other socially mediated pathways for understanding and promoting global warming as an issue in the public sphere. The article also places this historical overview of global warming as a public issue into a conceptual framework for understanding relationships between society and nature with emphasis on the co-construction of knowledge.

  8. Rangeland and warm-season forage grasses

    USDA-ARS?s Scientific Manuscript database

    Livestock ranchers depend on grassland grazing for a substantial part of their livestock management systems. Grassland forages make up to 85% of the feed supply for ruminant animal products, especially in warm climates. Grass breeding in general creates some unique breeding challenges ranging from...

  9. Desert Amplification in a Warming Climate.

    PubMed

    Zhou, Liming

    2016-08-19

    Here I analyze the observed and projected surface temperature anomalies over land between 50°S-50°N for the period 1950-2099 by large-scale ecoregion and find strongest warming consistently and persistently seen over driest ecoregions such as the Sahara desert and the Arabian Peninsula during various 30-year periods, pointing to desert amplification in a warming climate. This amplification enhances linearly with the global mean greenhouse gases(GHGs) radiative forcing and is attributable primarily to a stronger GHGs-enhanced downward longwave radiation forcing reaching the surface over drier ecoregions as a consequence of a warmer and thus moister atmosphere in response to increasing GHGs. These results indicate that desert amplification may represent a fundamental pattern of global warming associated with water vapor feedbacks over land in low- and mid- latitudes where surface warming rates depend inversely on ecosystem dryness. It is likely that desert amplification might involve two types of water vapor feedbacks that maximize respectively in the tropical upper troposphere and near the surface over deserts, with both being very dry and thus extremely sensitive to changes of water vapor.

  10. Frequency of Deep Convective Clouds and Global Warming

    NASA Technical Reports Server (NTRS)

    Aumann, Hartmut H.; Teixeira, Joao

    2008-01-01

    This slide presentation reviews the effect of global warming on the formation of Deep Convective Clouds (DCC). It concludes that nature responds to global warming with an increase in strong convective activity. The frequency of DCC increases with global warming at the rate of 6%/decade. The increased frequency of DCC with global warming alone increases precipitation by 1.7%/decade. It compares the state of the art climate models' response to global warming, and concludes that the parametrization of climate models need to be tuned to more closely emulate the way nature responds to global warming.

  11. Frequency of Deep Convective Clouds and Global Warming

    NASA Technical Reports Server (NTRS)

    Aumann, Hartmut H.; Teixeira, Joao

    2008-01-01

    This slide presentation reviews the effect of global warming on the formation of Deep Convective Clouds (DCC). It concludes that nature responds to global warming with an increase in strong convective activity. The frequency of DCC increases with global warming at the rate of 6%/decade. The increased frequency of DCC with global warming alone increases precipitation by 1.7%/decade. It compares the state of the art climate models' response to global warming, and concludes that the parametrization of climate models need to be tuned to more closely emulate the way nature responds to global warming.

  12. Physical Mechanisms of Rapid Lake Warming

    NASA Astrophysics Data System (ADS)

    Lenters, J. D.

    2016-12-01

    Recent studies have shown significant warming of inland water bodies around the world. Many lakes are warming more rapidly than the ambient surface air temperature, and this is counter to what is often expected based on the lake surface energy balance. A host of reasons have been proposed to explain these discrepancies, including changes in the onset of summer stratification, significant loss of ice cover, and concomitant changes in winter air temperature and/or summer cloud cover. A review of the literature suggests that no single physical mechanism is primarily responsible for the majority of these changes, but rather that the large heterogeneity in regional climate trends and lake geomorphometry results in a host of potential physical drivers. In this study, we discuss the variety of mechanisms that have been proposed to explain rapid lake warming and offer an assessment of the physical plausibility for each potential contributor. Lake Superior is presented as a case study to illustrate the "perfect storm" of factors that can cause a deep, dimictic lake to warm at rate that exceeds the rate of global air temperature warming by nearly an order of magnitude. In particular, we use a simple mixed-layer model to show that spatially variable trends in Lake Superior surface water temperature are determined, to first order, by variations in bathymetry and winter air temperature. Summer atmospheric conditions are often of less significance, and winter ice cover may simply be a correlate. The results highlight the importance of considering the full range of factors that can lead to trends in lake surface temperature, and that conventional wisdom may often not be the best guide.

  13. An apparent hiatus in global warming?

    NASA Astrophysics Data System (ADS)

    Trenberth, Kevin E.; Fasullo, John T.

    2013-12-01

    Global warming first became evident beyond the bounds of natural variability in the 1970s, but increases in global mean surface temperatures have stalled in the 2000s. Increases in atmospheric greenhouse gases, notably carbon dioxide, create an energy imbalance at the top-of-atmosphere (TOA) even as the planet warms to adjust to this imbalance, which is estimated to be 0.5-1 W m-2 over the 2000s. Annual global fluctuations in TOA energy of up to 0.2 W m-2 occur from natural variations in clouds, aerosols, and changes in the Sun. At times of major volcanic eruptions the effects can be much larger. Yet global mean surface temperatures fluctuate much more than these can account for. An energy imbalance is manifested not just as surface atmospheric or ground warming but also as melting sea and land ice, and heating of the oceans. More than 90% of the heat goes into the oceans and, with melting land ice, causes sea level to rise. For the past decade, more than 30% of the heat has apparently penetrated below 700 m depth that is traceable to changes in surface winds mainly over the Pacific in association with a switch to a negative phase of the Pacific Decadal Oscillation (PDO) in 1999. Surface warming was much more in evidence during the 1976-1998 positive phase of the PDO, suggesting that natural decadal variability modulates the rate of change of global surface temperatures while sea-level rise is more relentless. Global warming has not stopped; it is merely manifested in different ways.

  14. Respiratory muscle specific warm-up and elite swimming performance.

    PubMed

    Wilson, Emma E; McKeever, Tricia M; Lobb, Claire; Sherriff, Tom; Gupta, Luke; Hearson, Glenn; Martin, Neil; Lindley, Martin R; Shaw, Dominick E

    2014-05-01

    Inspiratory muscle training has been shown to improve performance in elite swimmers, when used as part of routine training, but its use as a respiratory warm-up has yet to be investigated. To determine the influence of inspiratory muscle exercise (IME) as a respiratory muscle warm-up in a randomised controlled cross-over trial. A total of 15 elite swimmers were assigned to four different warm-up protocols and the effects of IME on 100 m freestyle swimming times were assessed.Each swimmer completed four different IME warm-up protocols across four separate study visits: swimming-only warm-up; swimming warm-up plus IME warm-up (2 sets of 30 breaths with a 40% maximum inspiratory mouth pressure load using the Powerbreathe inspiratory muscle trainer); swimming warm-up plus sham IME warm-up (2 sets of 30 breaths with a 15% maximum inspiratory mouth pressure load using the Powerbreathe inspiratory muscle trainer); and IME-only warm-up. Swimmers performed a series of physiological tests and scales of perception (rate of perceived exertion and dyspnoea) at three time points (pre warm-up, post warm-up and post time trial). The combined standard swimming warm-up and IME warm-up were the fastest of the four protocols with a 100 m time of 57.05 s. This was significantly faster than the IME-only warm-up (mean difference=1.18 s, 95% CI 0.44 to 1.92, p<0.01) and the swim-only warm-up (mean difference=0.62 s, 95% CI 0.001 to 1.23, p=0.05). Using IME combined with a standard swimming warm-up significantly improves 100 m freestyle swimming performance in elite swimmers.

  15. Discrimination of a major stratospheric warming event in February-March 1984 from earlier minor warmings

    NASA Technical Reports Server (NTRS)

    Johnson, K. W.; Quiroz, R. S.; Gelman, M. E.

    1985-01-01

    As part of its responsibility for stratospheric monitoring, the Climate Analysis Center derives time trends of various dynamic parameters from NMC stratospheric analyses. Selected figures from this stratospheric monitoring data base are published in Climate Diagnostics Bulletin in March and October, after each hemispheric winter. During the Northern Hemisphere winter of December 1983-February 1984 several warming events may be seen in the plot of 60 deg. N zonal mean temperatures for 10 mb. Minor warmings may be noted in early December, late December, mid January and early February. A major warming with the 60 deg. N zonal mean temperatures reaching -40C is observed in late February, associated with a circulation reversal. In all of the minor warming episodes, there is a polarward movement of the Aleutian anticyclone; however, at 10 mb the North Pole remains in the cyclonic circulation of the stratospheric vortex which is not displaced far from its usual position. In the case of the later February major warming, the 10 mb circulation pattern over the North Pole is anticyclonic, and the cyclonic circulation has moved to the south and east with a considerable elongation. Cross sections of heat transport and momentum transport are not dramatically different for the minor and major warming episodes.

  16. Discrimination of a major stratospheric warming event in February-March 1984 from earlier minor warmings

    NASA Technical Reports Server (NTRS)

    Johnson, K. W.; Quiroz, R. S.; Gelman, M. E.

    1985-01-01

    As part of its responsibility for stratospheric monitoring, the Climate Analysis Center derives time trends of various dynamic parameters from NMC stratospheric analyses. Selected figures from this stratospheric monitoring data base are published in Climate Diagnostics Bulletin in March and October, after each hemispheric winter. During the Northern Hemisphere winter of December 1983-February 1984 several warming events may be seen in the plot of 60 deg. N zonal mean temperatures for 10 mb. Minor warmings may be noted in early December, late December, mid January and early February. A major warming with the 60 deg. N zonal mean temperatures reaching -40C is observed in late February, associated with a circulation reversal. In all of the minor warming episodes, there is a polarward movement of the Aleutian anticyclone; however, at 10 mb the North Pole remains in the cyclonic circulation of the stratospheric vortex which is not displaced far from its usual position. In the case of the later February major warming, the 10 mb circulation pattern over the North Pole is anticyclonic, and the cyclonic circulation has moved to the south and east with a considerable elongation. Cross sections of heat transport and momentum transport are not dramatically different for the minor and major warming episodes.

  17. Response of ocean ecosystems to climate warming

    NASA Astrophysics Data System (ADS)

    Sarmiento, J. L.; Slater, R.; Barber, R.; Bopp, L.; Doney, S. C.; Hirst, A. C.; Kleypas, J.; Matear, R.; Mikolajewicz, U.; Monfray, P.; Soldatov, V.; Spall, S. A.; Stouffer, R.

    2004-09-01

    We examine six different coupled climate model simulations to determine the ocean biological response to climate warming between the beginning of the industrial revolution and 2050. We use vertical velocity, maximum winter mixed layer depth, and sea ice cover to define six biomes. Climate warming leads to a contraction of the highly productive marginal sea ice biome by 42% in the Northern Hemisphere and 17% in the Southern Hemisphere, and leads to an expansion of the low productivity permanently stratified subtropical gyre biome by 4.0% in the Northern Hemisphere and 9.4% in the Southern Hemisphere. In between these, the subpolar gyre biome expands by 16% in the Northern Hemisphere and 7% in the Southern Hemisphere, and the seasonally stratified subtropical gyre contracts by 11% in both hemispheres. The low-latitude (mostly coastal) upwelling biome area changes only modestly. Vertical stratification increases, which would be expected to decrease nutrient supply everywhere, but increase the growing season length in high latitudes. We use satellite ocean color and climatological observations to develop an empirical model for predicting chlorophyll from the physical properties of the global warming simulations. Four features stand out in the response to global warming: (1) a drop in chlorophyll in the North Pacific due primarily to retreat of the marginal sea ice biome, (2) a tendency toward an increase in chlorophyll in the North Atlantic due to a complex combination of factors, (3) an increase in chlorophyll in the Southern Ocean due primarily to the retreat of and changes at the northern boundary of the marginal sea ice zone, and (4) a tendency toward a decrease in chlorophyll adjacent to the Antarctic continent due primarily to freshening within the marginal sea ice zone. We use three different primary production algorithms to estimate the response of primary production to climate warming based on our estimated chlorophyll concentrations. The three algorithms give

  18. Arctic decadal variability in a warming world

    NASA Astrophysics Data System (ADS)

    van der Linden, Eveline C.; Bintanja, Richard; Hazeleger, Wilco

    2017-04-01

    The Arctic is currently warming much faster than other parts of the world, and sea ice is rapidly diminishing. Superimposed on these temperature and sea ice trends is a strong decadal variability, which can reinforce or oppose the trends, depending on its phase. It is therefore imperative to know not only the characteristics of current variability but also how (patterns of) Arctic decadal variability (ADV) might change as the climate warms. We evaluated the ADV characteristics in three long, equilibrium climate simulations for present-day, doubled, and quadrupled atmospheric CO2 forcing. These simulations show that ADV changes non-linearly with increasing CO2 concentrations, with maximum variability occurring in the CO2 doubling climate when sea ice becomes more vulnerable to melt over vast stretches of the Arctic. The dominant region of variability, which is located over the Barents Sea and the Greenland Sea in the current climate, shifts to the central Arctic and Siberian regions as the climate warms. Furthermore, the links between dominant atmospheric circulation modes and Arctic climate characteristics vary strongly with climate change. For instance, a positive Arctic Oscillation (AO) index is associated with a colder Arctic region in warmer climates, instead of a warmer Arctic at present. Such changing relationships are partly related to the retreat of sea ice because altered wind patterns influence the sea ice distribution and hence the associated local surface fluxes. The atmospheric pressure distributions governing ADV also change with climate warming. The Aleutian and Icelandic Lows both play a key role in the changing mean state and the associated variability of the large-scale circulation. Whereas ocean heat transport is firmly associated with ADV in the current and the CO2 doubling climate, the importance of the atmospheric heat transport increases in even warmer climates, suggesting that the large-scale dynamics associated with ADV change as well. The

  19. Warm-adapted microbial communities enhance their carbon-use efficiency in warmed soils

    NASA Astrophysics Data System (ADS)

    Rousk, Johannes; Frey, Serita

    2017-04-01

    Ecosystem models predict that climate warming will stimulate microbial decomposition of soil carbon (C), resulting in a positive feedback to increasing temperatures. The current generation of models assume that the temperature sensitivities of microbial processes do not respond to warming. However, recent studies have suggested that the ability of microbial communities to adapt to warming can lead both strengthened and weakened feedbacks. A further complication is that the balance between microbial C used for growth to that used for respiration - the microbial carbon-use efficiency (CUE) - also has been shown through both modelling and empirical study to respond to warming. In our study, we set out to assess how chronic warming (+5°C over ambient during 9 years) of a temperate hardwood forest floor (Harvard Forest LTER, USA) affected temperature sensitivities of microbial processes in soil. To do this, we first determined the temperature relationships for bacterial growth, fungal growth, and respiration in plots exposed to warmed or ambient conditions. Secondly, we parametrised the established temperature functions microbial growth and respiration with plot-specific measured soil temperature data at a hourly time-resolution over the course of 3 years to estimate the real-time variation of in situ microbial C production and respiration. To estimate the microbial CUE, we also divided the microbial C production with the sum of microbial C production and respiration as a proxy for substrate use. We found that warm-adapted bacterial and fungal communities both shifted their temperature relationships to grow at higher rates in warm conditions which coincided with reduced rates at cool conditions. As such, their optimal temperature (Topt), minimum temperature (Tmin) and temperature sensitivity (Q10) were all increased. The temperature relationship for temperature, in contrast, was only marginally shifted in the same direction, but at a much smaller effect size, with

  20. Warm Rivers Play Role in Arctic Sea Ice Melt Animation

    NASA Image and Video Library

    2014-03-05

    This frame from a NASA MODIS animation depicts warming sea surface temperatures in the Arctic Beaufort Sea after warm waters from Canada Mackenzie River broke through a shoreline sea ice barrier in summer 2012, enhancing the melting of sea ice.

  1. OVERVIEW OF GOLD HILL MILL, ROAD, AND WARM SPRINGS CAMP ...

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

    OVERVIEW OF GOLD HILL MILL, ROAD, AND WARM SPRINGS CAMP BUILDINGS, LOOKING SOUTH SOUTHEAST. THE FUNCTION OF THE FLAT AREA AT CENTER RIGHT IS UNKNOWN. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA

  2. Isolating the anthropogenic component of Arctic warming

    SciTech Connect

    Chylek, Petr; Hengartner, Nicholas; Lesins, Glen; Klett, James D.; Humlum, Ole; Wyatt, Marcia; Dubey, Manvendra K.

    2014-05-28

    Structural equation modeling is used in statistical applications as both confirmatory and exploratory modeling to test models and to suggest the most plausible explanation for a relationship between the independent and the dependent variables. Although structural analysis cannot prove causation, it can suggest the most plausible set of factors that influence the observed variable. Here, we apply structural model analysis to the annual mean Arctic surface air temperature from 1900 to 2012 to find the most effective set of predictors and to isolate the anthropogenic component of the recent Arctic warming by subtracting the effects of natural forcing and variability from the observed temperature. We also find that anthropogenic greenhouse gases and aerosols radiative forcing and the Atlantic Multidecadal Oscillation internal mode dominate Arctic temperature variability. Finally, our structural model analysis of observational data suggests that about half of the recent Arctic warming of 0.64 K/decade may have anthropogenic causes.

  3. Isolating the anthropogenic component of Arctic warming

    DOE PAGES

    Chylek, Petr; Hengartner, Nicholas; Lesins, Glen; ...

    2014-05-28

    Structural equation modeling is used in statistical applications as both confirmatory and exploratory modeling to test models and to suggest the most plausible explanation for a relationship between the independent and the dependent variables. Although structural analysis cannot prove causation, it can suggest the most plausible set of factors that influence the observed variable. Here, we apply structural model analysis to the annual mean Arctic surface air temperature from 1900 to 2012 to find the most effective set of predictors and to isolate the anthropogenic component of the recent Arctic warming by subtracting the effects of natural forcing and variabilitymore » from the observed temperature. We also find that anthropogenic greenhouse gases and aerosols radiative forcing and the Atlantic Multidecadal Oscillation internal mode dominate Arctic temperature variability. Finally, our structural model analysis of observational data suggests that about half of the recent Arctic warming of 0.64 K/decade may have anthropogenic causes.« less

  4. Parameters of human discomfort in warm environments

    SciTech Connect

    Berglund, L.G.; Cunningham, D.J.

    1986-01-01

    The relationship between thermoregulatory responses during exposure to warm and hot environments and the associated subjective perceptions, e.g., comfort, thermal sensation, etc., have been studied by numerous investigators over a considerable span of time, i.e., roughly 50 years. Skin temperature, mean body temperature, sweating, and percent of skin wettedness have been shown to have a role in comfort, thermal sensation, and perception of skin moisture. This paper reviews studies concerned with the physical and physiological parameters relative to these subjective responses and their level of magnitude, with primary emphasis on warm discomfort and skin moisture. The review indicates that, while utilizing different methodologies for quantification of skin moisture under a wide range of ambient conditions and experimental protocols, the relationship between skin wettedness and discomfort or unpleasantness is consistent and experimentally supported.

  5. Cognitive Egocentrism Differentiates Warm and Cold People.

    PubMed

    Boyd, Ryan L; Bresin, Konrad; Ode, Scott; Robinson, Michael D

    2013-02-01

    Warmth-coldness is a fundamental dimension of social behavior. Cold individuals are egocentric in their social relations, whereas warm individuals are not. Previous theorizing suggests that cognitive egocentrism underlies social egocentrism. It was hypothesized that higher levels of interpersonal coldness would predict greater cognitive egocentrism. Cognitive egocentrism was assessed in basic terms through tasks wherein priming a lateralized self-state biased subsequent visual perceptions in an assimilation-related manner. Such effects reflect a tendency to assume that the self's incidental state provides meaningful information concerning the external world. Cognitive egocentrism was evident at high, but not low, levels of interpersonal coldness. The findings reveal a basic difference between warm and cold people, encouraging future research linking cognitive egocentrism to variability in relationship functioning.

  6. Environmental colonialism Leadership and global warming

    SciTech Connect

    Not Available

    1990-02-16

    The vast majority of the world's scientific community believes there is global warming and that it is global problem requiring international cooperation. But policy makers in industrialized countries are at a crossroads:Listen to the skeptics, who demand more proof and who fear economic consequences of an anti-greenhouse campaign, or take the more difficult path of commitment to attacking the problem. Meanwhile, poverty and debt keep. The Third world locked out of any active partnership. This issue of ED highlight their results of recently tapping documents and seminar findings on the subject of global warming. This issue also contains the following: (1) ED Refining Netback Data Series for the US Gulf and West Coasts, Rotterdam, and Singapore as of the February 9, 1990; and (2) ED Fuel Price/Tax Series for countries of the Western Hemisphere, February 1990 edition. 6 figs., 5 tabs.

  7. Giant natural fluctuation models and anthropogenic warming

    NASA Astrophysics Data System (ADS)

    Lovejoy, S.; Rio Amador, L.; Hébert, R.; Lima, I.

    2016-08-01

    Explanations for the industrial epoch warming are polarized around the hypotheses of anthropogenic warming (AW) and giant natural fluctuations (GNFs). While climate sceptics have systematically attacked AW, up until now they have only invoked GNFs. This has now changed with the publication by D. Keenan of a sample of 1000 series from stochastic processes purporting to emulate the global annual temperature since 1880. While Keenan's objective was to criticize the International Panel on Climate Change's trend uncertainty analysis (their assumption that residuals are only weakly correlated), for the first time it is possible to compare a stochastic GNF model with real data. Using Haar fluctuations, probability distributions, and other techniques of time series analysis, we show that his model has unrealistically strong low-frequency variability so that even mild extrapolations imply ice ages every ≈1000 years. Helped by statistics, the GNF model can easily be scientifically rejected.

  8. Viscous warm inflation: Hamilton-Jacobi formalism

    NASA Astrophysics Data System (ADS)

    Akhtari, L.; Mohammadi, A.; Sayar, K.; Saaidi, Kh.

    2017-04-01

    Using Hamilton-Jacobi formalism, the scenario of warm inflation with viscous pressure is considered. The formalism gives a way of computing the slow-rolling parameter without extra approximation, and it is well-known as a powerful method in cold inflation. The model is studied in detail for three different cases of the dissipation and bulk viscous pressure coefficients. In the first case where both coefficients are taken as constant, it is shown that the case could not portray warm inflationary scenario compatible with observational data even it is possible to restrict the model parameters. For other cases, the results shows that the model could properly predicts the perturbation parameters in which they stay in perfect agreement with Planck data. As a further argument, r -ns and αs -ns are drown that show the acquired result could stand in acceptable area expressing a compatibility with observational data.

  9. Warm Debris Disk Candidates from WISE

    NASA Technical Reports Server (NTRS)

    Padgett, Deborah; Stapelfeldt, Karl; Liu, Wilson; Leisawitz, David

    2011-01-01

    The Wide Field Infrared Survey Explorer (WISE) has just completed a sensitive all-sky survey in photometric bands at 3.4, 4.6, 12, and 22 microns. We report on a preliminary investigation of main sequence Hipparcos and Tycho catalog stars with 22 micron emission in excess of photospheric levels. This warm excess emission traces material in the circumstellar region likely to host terrestrial planets and is preferentially found in young systems with ages < 1 Gyr. Nearly a hundred new warm debris disk candidates are detected among FGK stars and 150 A stars within 120 pc. We are in the process of obtaining spectra to determine spectral types and activity level of these stars and are using HST, Herschel and Keck to characterize the dust, multiplicity, and substellar companions of these systems. In this contribution, we will discuss source selection methods and individual examples from among the WISE debris disk candidates.

  10. Latitudinal distribution of the recent Arctic warming

    SciTech Connect

    Chylek, Petr; Lesins, Glen K; Wang, Muyin

    2010-12-08

    Increasing Arctic temperature, disappearance of Arctic sea ice, melting of the Greenland ice sheet, sea level rise, increasing strength of Atlantic hurricanes are these impending climate catastrophes supported by observations? Are the recent data really unprecedented during the observational records? Our analysis of Arctic temperature records shows that the Arctic and temperatures in the 1930s and 1940s were almost as high as they are today. We argue that the current warming of the Arctic region is affected more by the multi-decadal climate variability than by an increasing concentration of carbon dioxide. Unfortunately, none of the existing coupled Atmosphere-Ocean General Circulation Models used in the IPCC 2007 cIimate change assessment is able to reproduce neither the observed 20th century Arctic cIimate variability nor the latitudinal distribution of the warming.

  11. Early Eocene climate warming increased petroleum production

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2012-04-01

    From the late Paleocene, about 58 million years ago, to the early Eocene, about 51 million years ago, Earth's surface temperatures warmed by about 5°-10°C. Also in the early Eocene, there was an increase of carbon-13-depleted carbon in the oceans that cannot be accounted for by changes in carbon cycling at the surface. To better understand the source of that carbon, Kroeger and Funnell modeled the thermal evolution of four sedimentary basins in the southwestern Pacific Ocean. The authors show that the rising surface temperatures of the early Eocene eventually led to warming of the sedimentary beds deep beneath the surface. Petroleum can be produced at only a certain range of temperatures; rising temperatures at greater depths would bring more potential source rocks into temperature conditions under which oil and gas can be produced and released.

  12. AGN warm absorption with the ATHENA

    NASA Astrophysics Data System (ADS)

    Różańska, Agata; Gronkiewicz, Dominik; Hryniewicz, Krzysztof; Adhikari, Tek Prasad; Rataj, Mirosław; Skup, Konrad

    2016-06-01

    X-ray astronomy requires satellites to make progress in searching the distribution of hot matter in the Universe. Approximately 15 years period of time is needed for full construction of the flight instrument from the mission concept up to the launch. A new generation X-ray telescope ATHENA (the Advanced Telescope for High Energy Astrophysics) was approved by European Space Agency as a large mission with a launch foreseen in 2028. In this paper we show how microcalorimeter on the board of ATHENA will help us to study warm absorption observed in active galactic nuclei (AGN). We show that future observations will allow us to identify hundreds of lines from highly ionized elements and to measure Galactic warm absorption with very high precision.

  13. [LEVEL 1--a new blood warming device].

    PubMed

    Arndt, M; Hofmockel, R; Benad, G

    1994-01-01

    Hypothermia of less than 35 degrees C, which frequently occurs in connection with massive blood transfusion, is a serious problem in many patients, in particular in those with polytrauma. The restoration of normal body temperature is very important and requires the use of a rapidly-acting, efficient and safe blood warmer, which is able to work effectively at high flow-rates. The LEVEL 1 (Technologies, Rockland, MA) is such a new blood warmer and works as a heat-exchanger via an aluminium column. This system is highly effective. Six hundred ml of sodium chloride 0.9% are warmed from 4 to 35 degrees C within one minute. This device is quickly operational and has a low priming volume. The LEVEL 1 is the only device currently available which is able to warm blood sufficiently during a very rapid blood transfusion.

  14. Indian Ocean warming modulates Pacific climate change.

    PubMed

    Luo, Jing-Jia; Sasaki, Wataru; Masumoto, Yukio

    2012-11-13

    It has been widely believed that the tropical Pacific trade winds weakened in the last century and would further decrease under a warmer climate in the 21st century. Recent high-quality observations, however, suggest that the tropical Pacific winds have actually strengthened in the past two decades. Precise causes of the recent Pacific climate shift are uncertain. Here we explore how the enhanced tropical Indian Ocean warming in recent decades favors stronger trade winds in the western Pacific via the atmosphere and hence is likely to have contributed to the La Niña-like state (with enhanced east-west Walker circulation) through the Pacific ocean-atmosphere interactions. Further analysis, based on 163 climate model simulations with centennial historical and projected external radiative forcing, suggests that the Indian Ocean warming relative to the Pacific's could play an important role in modulating the Pacific climate changes in the 20th and 21st centuries.

  15. Magnetic fusion development for global warming suppression

    NASA Astrophysics Data System (ADS)

    Li, Jiangang; Zhang, Jie; Duan, Xuru

    2010-01-01

    Energy shortage and environmental pollution are two critical issues for human beings in the 21st century. There is an urgent need for new sustainable energy to meet the fast growing demand for clean energy. Fusion is one of the few options which may be able to satisfy the requirement for large scale sustainable energy generation and global warming suppression and therefore must be developed as quickly as possible. Fusion research has been carried out for the past 50 years. It is too long to wait for another 50 years to generate electricity by fusion. A much more aggressive approach should be taken with international collaboration towards the early use of fusion energy to meet the urgent needs for energy and global warming suppression.

  16. The winter anomaly and sudden stratospheric warmings

    NASA Astrophysics Data System (ADS)

    Lastovicka, J.

    1984-08-01

    Large-scale stratospheric warmings are examined on the basis of 22-year measurements of radio-wave absorption at the Panska Ves observatory. It is shown that these warmings, accompanied by the reversal of wind direction in the lower thermosphere, lead not to an increase but to a decrease in the radio-wave absorption in the lower ionosphere, i.e., to the disappearance of the winter anomaly. It is concluded that the absorption decrease is connected not only with cooling in the mesopause region but also with a total change in the dynamic conditions of the lower ionosphere. The behavior of the winter anomaly in the 1979-1980 and 1981-1982 periods is examined in detail.

  17. Winter warming from large volcanic eruptions

    SciTech Connect

    Robock, A.; Jianping Mao )

    1992-12-24

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

  18. Indian Ocean warming modulates Pacific climate change

    PubMed Central

    Luo, Jing-Jia; Sasaki, Wataru; Masumoto, Yukio

    2012-01-01

    It has been widely believed that the tropical Pacific trade winds weakened in the last century and would further decrease under a warmer climate in the 21st century. Recent high-quality observations, however, suggest that the tropical Pacific winds have actually strengthened in the past two decades. Precise causes of the recent Pacific climate shift are uncertain. Here we explore how the enhanced tropical Indian Ocean warming in recent decades favors stronger trade winds in the western Pacific via the atmosphere and hence is likely to have contributed to the La Niña-like state (with enhanced east–west Walker circulation) through the Pacific ocean–atmosphere interactions. Further analysis, based on 163 climate model simulations with centennial historical and projected external radiative forcing, suggests that the Indian Ocean warming relative to the Pacific’s could play an important role in modulating the Pacific climate changes in the 20th and 21st centuries. PMID:23112174

  19. Isolating the anthropogenic component of Arctic warming

    NASA Astrophysics Data System (ADS)

    Chylek, Petr; Hengartner, Nicholas; Lesins, Glen; Klett, James D.; Humlum, Ole; Wyatt, Marcia; Dubey, Manvendra K.

    2014-05-01

    Structural equation modeling is used in statistical applications as both confirmatory and exploratory modeling to test models and to suggest the most plausible explanation for a relationship between the independent and the dependent variables. Although structural analysis cannot prove causation, it can suggest the most plausible set of factors that influence the observed variable. We apply structural model analysis to the annual mean Arctic surface air temperature from 1900 to 2012 to find the most effective set of predictors and to isolate the anthropogenic component of the recent Arctic warming by subtracting the effects of natural forcing and variability from the observed temperature. We find that anthropogenic greenhouse gases and aerosols radiative forcing and the Atlantic Multidecadal Oscillation internal mode dominate Arctic temperature variability. Our structural model analysis of observational data suggests that about half of the recent Arctic warming of 0.64 K/decade may have anthropogenic causes.

  20. Policies on global warming and ozone depletion

    SciTech Connect

    Green, B.

    1987-04-01

    The recent discovery of a dramatic seasonal drop in the amount of ozone over Antarctica has catalyzed concern for protection of stratospheric ozone, the layer of gas that shields the entire planet from excess ultraviolet radiation. Conservative scientific models predict about a 5% reduction in the amount of global ozone by the middle of the next century, with large local variations. The predicted global warming from increased emissions of greenhouse gases will also have differing effects on local climate and weather conditions and consequently on agriculture. Although numerous uncertainties are associated with both ozone depletion and a global warming, there is a consensus that world leaders need to address the problems. The US Congress is now beginning to take note of the task. In this article, one representative outlines some perceptions of the problems and the policy options available to Congress.

  1. Management of drought risk under global warming

    NASA Astrophysics Data System (ADS)

    Zhang, Qiang; Han, Lanying; Jia, Jianying; Song, Lingling; Wang, Jinsong

    2016-07-01

    Drought is a serious ecological problem around the world, and its impact on crops and water availability for humans can jeopardize human life. Although drought has always been common, the drought risk has become increasingly prominent because of the climatic warming that has occurred during the past century. However, it still does not comprehensively understand the mechanisms that determine the occurrence of the drought risk it poses to humans, particularly in the context of global climate change. In this paper, we summarize the progress of research on drought and the associated risk, introduce the principle of a drought "transition" from one stage to another, synthesize the characteristics of key factors and their interactions, discuss the potential effect of climatic warming on drought risk, and use this discussion to define the basic requirements for a drought risk management system. We also discuss the main measures that can be used to prevent or mitigate droughts in the context of a risk management strategy.

  2. Cognitive Egocentrism Differentiates Warm and Cold People

    PubMed Central

    Boyd, Ryan L.; Bresin, Konrad; Ode, Scott; Robinson, Michael D.

    2012-01-01

    Warmth-coldness is a fundamental dimension of social behavior. Cold individuals are egocentric in their social relations, whereas warm individuals are not. Previous theorizing suggests that cognitive egocentrism underlies social egocentrism. It was hypothesized that higher levels of interpersonal coldness would predict greater cognitive egocentrism. Cognitive egocentrism was assessed in basic terms through tasks wherein priming a lateralized self-state biased subsequent visual perceptions in an assimilation-related manner. Such effects reflect a tendency to assume that the self's incidental state provides meaningful information concerning the external world. Cognitive egocentrism was evident at high, but not low, levels of interpersonal coldness. The findings reveal a basic difference between warm and cold people, encouraging future research linking cognitive egocentrism to variability in relationship functioning. PMID:23564985

  3. The Effect of Arousal on Warm Up Decrement.

    ERIC Educational Resources Information Center

    Anshel, Mark H.

    1985-01-01

    This study examined whether particular strategies would enhance affective arousal and if these techniques would affect warm-up decrement during performance of a sport skill. One strategy eliminated warm-up decrement and two had no effect. Positive and negative arousal and the correlation of arousal level to warm-up decrement are explored.…

  4. Warm up practices of golfers: are they adequate?

    PubMed Central

    Fradkin, A; Finch, C; Sherman, C

    2001-01-01

    Background—Although it is widely recommended that golfers warm up before play or practice to enhance their physical performance and reduce their injury risk, it is not known to what extent they actually undertake such warm up procedures. Objective—To collect information about the proportion of golfers who actively warm up and to determine the types of warm up behaviours. Methods—This study was conducted over three weeks at three different golfing venues: a private golf course, a public golf course, and a golf driving range. Golfers' warm up behaviours, defined as any form of preparative exercise, were recorded by direct observation by two independent observers. Results—The sample consisted of 1040 amateur golfers (852 men and 188 women) aged at least 18 years. Only 54.3% (95% confidence interval 49.8 to 58.8) performed some form of warm up activity. Air swings on the tee were the most commonly observed warm up activity, with 88.7% (95% confidence interval 85.9 to 91.5) of golfers who warmed up performing these. Conclusions—Only a small proportion of amateur golfers perform appropriate warm up exercises. To improve on this, golfers should be educated about the possible benefits of warming up and be shown how to perform an appropriate warm up routine. Key Words: behaviour; observational study; golf; warm up; injury prevention PMID:11273975

  5. Likely cause found for global warming "hiatus"

    NASA Astrophysics Data System (ADS)

    Wendel, JoAnna

    2014-08-01

    An Atlantic current may be the cause of the recent warming "hiatus" observed since the beginning of the 21st century, according to new research published last week in the journal Science (doi:10.1126/science.1254937). The conclusion is based on observations of deep-sea temperatures in the Atlantic Ocean, from floats that sample water down to 2000 meters deep and from looking at historical records from the mid- to late 20th century.

  6. Pre-warming of dental composites.

    PubMed

    Deb, Sanjukta; Di Silvio, Lucy; Mackler, Harrison E; Millar, Brian J

    2011-04-01

    Cavity lining with flowable composites have been proposed to improve initial marginal adaptation and minimize shrinkage stresses. The purpose of this study was to evaluate if prewarming of composites would influence the flow and enhance marginal adaptation thus the effect of pre-warming different types of composites on their properties are reported. Six different composites were used in this study including a flowable and a polyacid modified composite. Uncured composites were pressed between two glass plates with a known load and the film thickness was measured to determine flow. Polymerization shrinkage was measured by means of a one-dimension contacting transducer. Flexural strength was determined using a three-point bend test. Microleakage was determined in human lower third molars on both enamel and dentin restoration interfaces. Cytocompatibility was analyzed with an Alamar Blue redox cell proliferation assay. The flow properties, linear shrinkage, flexural strength, microleakage and cytocompatibility were evaluated at 22 °C and 60 °C. The results indicated that the film thickness for each of the materials was significantly lower at 60 °C and the linear shrinkage was greater as a result of the higher degree of polymerization. The flexural strength of Spectrum TPH and Wave were found to be statistically significantly higher with pre-warming, however the other composites did not exhibit any differences. Microleakage studies showed that pre-warming had no significant bearing on the results and alamarBlue(®) results showed that the pre-heating did not have an effect on the cytotoxicity however the levels of cytotoxicity varied between the composites that can be attributed to the composition. Pre-warming of the composites studied enhanced flow as observed by measuring film thickness and did not significantly affect other properties. Copyright © 2010. Published by Elsevier Ltd.

  7. A global warning for global warming

    SciTech Connect

    Paepe, R.

    1996-12-31

    The problem of global warming is a complex one not only because it is affecting desert areas such as the Sahel leading to famine disasters of poor rural societies, but because it is an even greater threat to modern well established industrial societies. Global warming is a complex problem of geographical, economical and societal factors together which definitely are biased by local environmental parameters. There is an absolute need to increase the knowledge of such parameters, especially to understand their limits of variance. The greenhouse effect is a global mechanism which means that in changing conditions at one point of the Earth, it will affect all other regions of the globe. Industrial pollution and devastation of the forest are quoted as similar polluting anthropogenic activities in far apart regions of the world with totally different societies and industrial compounds. The other important factor is climatic cyclicity which means that droughts are bound to natural cycles. These natural cycles are numerous as is reflected in the study of geo-proxydata from several sequential geological series on land, ice and deepsea. Each of these cycles reveals a drought cycle which occasionally interfere at the same time. It is believed that the present drought might well be a point of interference between the natural cycles of 2,500 and 1,000 years and the man induced cycle of the last century`s warming up. If the latter is the only cycle involved, man will be able to remediate. If not, global warming will become even more disastrous beyond the 21st century.

  8. Response to Skeptics of Global Warming.

    NASA Astrophysics Data System (ADS)

    Kellogg, William W.

    1991-04-01

    The majority of the scientific community involved in climate research is convinced of the reality of a current and future global warming due to the greenhouse effect, a change that must be largely caused by human activities. However, a minority of scientists is still skeptical of the notion that mankind is significantly influencing the climate of the earth, and it therefore argues against taking certain measures to avert this alleged global warming. In recent years the media have given considerable coverage to the statements of these skeptics. Reasons for their statements range from a simple argument that we do not understand the earth's climate system well enough to predict the future, to more complex arguments involving negative feed-backs and changes of solar activity. They question whether the global temperature increase in this century of up to 0.6 K is primarily a result of worldwide burning of fossil fuels. The purpose of this article is to show that the statements of this skeptical school of thought need to be critically analyzed (and in some cases refuted) in the light of current understanding of the planetary system that determines our climate. There is also another school of thought that agrees about the reality of present and future global warming, and claims that this will be beneficial for most of mankind and that it should be encouraged. The policy implications of the latter view are in many respects similar to those of the group that are not convinced that a significant global warming will occur. Both schools of thought argue against taking immediate steps to slow the climate change.

  9. Warm-intermediate inflationary universe model

    SciTech Connect

    Campo, Sergio del; Herrera, Ramon E-mail: ramon.herrera@ucv.cl

    2009-04-15

    Warm inflationary universe models in the context of intermediate expansion, between power law and exponential, are studied. General conditions required for these models to be realizable are derived and discussed. This study is done in the weak and strong dissipative regimes. The inflaton potentials considered in this study are negative-power-law and powers of logarithms, respectively. The parameters of our models are constrained from the WMAP three and five year data.

  10. Robust warming of the global upper ocean.

    PubMed

    Lyman, John M; Good, Simon A; Gouretski, Viktor V; Ishii, Masayoshi; Johnson, Gregory C; Palmer, Matthew D; Smith, Doug M; Willis, Josh K

    2010-05-20

    A large ( approximately 10(23) J) multi-decadal globally averaged warming signal in the upper 300 m of the world's oceans was reported roughly a decade ago and is attributed to warming associated with anthropogenic greenhouse gases. The majority of the Earth's total energy uptake during recent decades has occurred in the upper ocean, but the underlying uncertainties in ocean warming are unclear, limiting our ability to assess closure of sea-level budgets, the global radiation imbalance and climate models. For example, several teams have recently produced different multi-year estimates of the annually averaged global integral of upper-ocean heat content anomalies (hereafter OHCA curves) or, equivalently, the thermosteric sea-level rise. Patterns of interannual variability, in particular, differ among methods. Here we examine several sources of uncertainty that contribute to differences among OHCA curves from 1993 to 2008, focusing on the difficulties of correcting biases in expendable bathythermograph (XBT) data. XBT data constitute the majority of the in situ measurements of upper-ocean heat content from 1967 to 2002, and we find that the uncertainty due to choice of XBT bias correction dominates among-method variability in OHCA curves during our 1993-2008 study period. Accounting for multiple sources of uncertainty, a composite of several OHCA curves using different XBT bias corrections still yields a statistically significant linear warming trend for 1993-2008 of 0.64 W m(-2) (calculated for the Earth's entire surface area), with a 90-per-cent confidence interval of 0.53-0.75 W m(-2).

  11. [Global warming and spread of infectious diseases].

    PubMed

    Ebert, B; Fleischer, B

    2005-01-01

    At the end of the twentieth century, tropical infectious diseases increased despite earlier successes of eradication campaigns. As a global warming of 1.4-5.8 degrees C is anticipated to occur by 2100, mainly the vector-borne tropical diseases that are particularly sensitive to climate are expected to spread. Although biological reasons seemingly support this hypothesis, ecological and socioeconomic factors have in the past proven to be stronger driving forces for the spread of infectious disease than climate.

  12. Effects of Global Warming on Vibrio Ecology.

    PubMed

    Vezzulli, Luigi; Pezzati, Elisabetta; Brettar, Ingrid; Höfle, Manfred; Pruzzo, Carla

    2015-06-01

    Vibrio-related infections are increasing worldwide both in humans and aquatic animals. Rise in global sea surface temperature (SST), which is approximately 1 °C higher now than 140 years ago and is one of the primary physical impacts of global warming, has been linked to such increases. In this chapter, major known effects of increasing SST on the biology and ecology of vibrios are described. They include the effects on bacterial growth rate, both in the field and in laboratory, culturability, expression of pathogenicity traits, and interactions with aquatic organisms and abiotic surfaces. Special emphasis is given to the effect of ocean warming on Vibrio interactions with zooplankters, which represent one of the most important aquatic reservoirs for these bacteria. The reported findings highlight the biocomplexity of the interactions between vibrios and their natural environment in a climate change scenario, posing the need for interdisciplinary studies to properly understand the connection between ocean warming and persistence and spread of vibrios in sea waters and the epidemiology of the diseases they cause.

  13. Global Warming: Evidence from Satellite Observations

    NASA Technical Reports Server (NTRS)

    Prabhakara, C.; Iacovazzi, R.; Yoo, J.-M.; Dalu, G.; Einaudi, Franco (Technical Monitor)

    2000-01-01

    Observations made in Channel 2 (53.74 GHz) of the Microwave Sounding Unit (MSU) radiometer, flown onboard sequential, sun-synchronous, polar-orbiting NOAA (National Oceanic and Atmospheric Administration) operational satellites, indicate that the mean temperature of the atmosphere over the globe increased during the period 1980 to 1999. In this study, we have minimized systematic errors in the time series introduced by satellite orbital drift in an objective manner. This is done with the help of the onboard warm-blackbody temperature, which is used in the calibration of the MSU radiometer. The corrected MSU Channel 2 observations of the NOAA satellite series reveal that the vertically-weighted global-mean temperature of the atmosphere, with a peak weight near the mid troposphere, warmed at the rate of 0.13 +/- 0.05 K/decade during 1980 to 1999. The global warming deduced from conventional meteorological data that have been corrected for urbanization effects agrees reasonably with this satellite-deduced result.

  14. Global warming and allergy in Asia Minor.

    PubMed

    Bajin, Munir Demir; Cingi, Cemal; Oghan, Fatih; Gurbuz, Melek Kezban

    2013-01-01

    The earth is warming, and it is warming quickly. Epidemiological studies have demonstrated that global warming is correlated with the frequency of pollen-induced respiratory allergy and allergic diseases. There is a body of evidence suggesting that the prevalence of allergic diseases induced by pollens is increasing in developed countries, a trend that is also evident in the Mediterranean area. Because of its mild winters and sunny days with dry summers, the Mediterranean area is different from the areas of central and northern Europe. Classical examples of allergenic pollen-producing plants of the Mediterranean climate include Parietaria, Olea and Cupressaceae. Asia Minor is a Mediterranean region that connects Asia and Europe, and it includes considerable coastal areas. Gramineae pollens are the major cause of seasonal allergic rhinitis in Asia Minor, affecting 1.3-6.4 % of the population, in accordance with other European regions. This article emphasizes the importance of global climate change and anticipated increases in the prevalence and severity of allergic disease in Asia Minor, mediated through worsening air pollution and altered local and regional pollen production, from an otolaryngologic perspective.

  15. Atmospheric footprint of the recent warming slowdown

    PubMed Central

    Liu, Bo; Zhou, Tianjun

    2017-01-01

    Growing body of literature has developed to detect the role of ocean heat uptake and transport in the recent warming slowdown between 1998–2013; however, the atmospheric footprint of the slowdown in dynamical and physical processes remains unclear. Here, we divided recent decades into the recent hiatus period and the preceding warming period (1983–1998) to investigate the atmospheric footprint. We use a process-resolving analysis method to quantify the contributions of different processes to the total temperature changes. We show that the increasing rate of global mean tropospheric temperature was also reduced during the hiatus period. The decomposed trends due to physical processes, including surface albedo, water vapour, cloud, surface turbulent fluxes and atmospheric dynamics, reversed the patterns between the two periods. The changes in atmospheric heat transport are coupled with changes in the surface latent heat flux across the lower troposphere (below approximately 800 hPa) and with cloud-related processes in the upper troposphere (above approximately 600 hPa) and were underpinned by strengthening/weakening Hadley Circulation and Walker Circulation during the warming/hiatus period. This dynamical coupling experienced a phase transition between the two periods, reminding us of the importance of understanding the atmospheric footprint, which constitutes an essential part of internal climate variability. PMID:28084457

  16. Atmospheric footprint of the recent warming slowdown.

    PubMed

    Liu, Bo; Zhou, Tianjun

    2017-01-13

    Growing body of literature has developed to detect the role of ocean heat uptake and transport in the recent warming slowdown between 1998-2013; however, the atmospheric footprint of the slowdown in dynamical and physical processes remains unclear. Here, we divided recent decades into the recent hiatus period and the preceding warming period (1983-1998) to investigate the atmospheric footprint. We use a process-resolving analysis method to quantify the contributions of different processes to the total temperature changes. We show that the increasing rate of global mean tropospheric temperature was also reduced during the hiatus period. The decomposed trends due to physical processes, including surface albedo, water vapour, cloud, surface turbulent fluxes and atmospheric dynamics, reversed the patterns between the two periods. The changes in atmospheric heat transport are coupled with changes in the surface latent heat flux across the lower troposphere (below approximately 800 hPa) and with cloud-related processes in the upper troposphere (above approximately 600 hPa) and were underpinned by strengthening/weakening Hadley Circulation and Walker Circulation during the warming/hiatus period. This dynamical coupling experienced a phase transition between the two periods, reminding us of the importance of understanding the atmospheric footprint, which constitutes an essential part of internal climate variability.

  17. Atmospheric footprint of the recent warming slowdown

    NASA Astrophysics Data System (ADS)

    Liu, Bo; Zhou, Tianjun

    2017-01-01

    Growing body of literature has developed to detect the role of ocean heat uptake and transport in the recent warming slowdown between 1998–2013 however, the atmospheric footprint of the slowdown in dynamical and physical processes remains unclear. Here, we divided recent decades into the recent hiatus period and the preceding warming period (1983–1998) to investigate the atmospheric footprint. We use a process-resolving analysis method to quantify the contributions of different processes to the total temperature changes. We show that the increasing rate of global mean tropospheric temperature was also reduced during the hiatus period. The decomposed trends due to physical processes, including surface albedo, water vapour, cloud, surface turbulent fluxes and atmospheric dynamics, reversed the patterns between the two periods. The changes in atmospheric heat transport are coupled with changes in the surface latent heat flux across the lower troposphere (below approximately 800 hPa) and with cloud-related processes in the upper troposphere (above approximately 600 hPa) and were underpinned by strengthening/weakening Hadley Circulation and Walker Circulation during the warming/hiatus period. This dynamical coupling experienced a phase transition between the two periods, reminding us of the importance of understanding the atmospheric footprint, which constitutes an essential part of internal climate variability.

  18. The phenology of Arctic Ocean surface warming.

    PubMed

    Steele, Michael; Dickinson, Suzanne

    2016-09-01

    In this work, we explore the seasonal relationships (i.e., the phenology) between sea ice retreat, sea surface temperature (SST), and atmospheric heat fluxes in the Pacific Sector of the Arctic Ocean, using satellite and reanalysis data. We find that where ice retreats early in most years, maximum summertime SSTs are usually warmer, relative to areas with later retreat. For any particular year, we find that anomalously early ice retreat generally leads to anomalously warm SSTs. However, this relationship is weak in the Chukchi Sea, where ocean advection plays a large role. It is also weak where retreat in a particular year happens earlier than usual, but still relatively late in the season, primarily because atmospheric heat fluxes are weak at that time. This result helps to explain the very different ocean warming responses found in two recent years with extreme ice retreat, 2007 and 2012. We also find that the timing of ice retreat impacts the date of maximum SST, owing to a change in the ocean surface buoyancy and momentum forcing that occurs in early August that we term the Late Summer Transition (LST). After the LST, enhanced mixing of the upper ocean leads to cooling of the ocean surface even while atmospheric heat fluxes are still weakly downward. Our results indicate that in the near-term, earlier ice retreat is likely to cause enhanced ocean surface warming in much of the Arctic Ocean, although not where ice retreat still occurs late in the season.

  19. Global Warming: Evidence from Satellite Observations

    NASA Technical Reports Server (NTRS)

    Prabhakara, C.; Iacovazzi, R., Jr.; Yoo, J.-M.

    2001-01-01

    Observations made in Channel 2 (53.74 GHz) of the Microwave Sounding Unit (MSU) radiometer, flown on-board sequential, sun-synchronous, polar orbiting NOAA operational satellites, indicate that the mean temperature of the atmosphere over the globe increased during the period 1980 to 1999. In this study we have minimized systematic errors in the time series introduced by the satellite orbital drift in an objective manner. This is done with the help the onboard warm black body temperature, which is used in the calibration of the MSU radiometer. The corrected MSU Channel 2 observations of the NOAA satellite series reveal that the vertically weighted global mean temperature of the atmosphere, with a peak weight near the mid-troposphere, warmed at the rate of 0.13 K per decade (with an uncertainty of 0.05 K per decade) during 1980 to 1999. The global warming deduced from conventional meteorological data that have been corrected for urbanization effects agrees reasonably with this satellite deuced result.

  20. Scientists' views about attribution of global warming.

    PubMed

    Verheggen, Bart; Strengers, Bart; Cook, John; van Dorland, Rob; Vringer, Kees; Peters, Jeroen; Visser, Hans; Meyer, Leo

    2014-08-19

    Results are presented from a survey held among 1868 scientists studying various aspects of climate change, including physical climate, climate impacts, and mitigation. The survey was unique in its size, broadness and level of detail. Consistent with other research, we found that, as the level of expertise in climate science grew, so too did the level of agreement on anthropogenic causation. 90% of respondents with more than 10 climate-related peer-reviewed publications (about half of all respondents), explicitly agreed with anthropogenic greenhouse gases (GHGs) being the dominant driver of recent global warming. The respondents' quantitative estimate of the GHG contribution appeared to strongly depend on their judgment or knowledge of the cooling effect of aerosols. The phrasing of the IPCC attribution statement in its fourth assessment report (AR4)-providing a lower limit for the isolated GHG contribution-may have led to an underestimation of the GHG influence on recent warming. The phrasing was improved in AR5. We also report on the respondents' views on other factors contributing to global warming; of these Land Use and Land Cover Change (LULCC) was considered the most important. Respondents who characterized human influence on climate as insignificant, reported having had the most frequent media coverage regarding their views on climate change.

  1. Stratosphere-Troposphere Coupling During Sudden Warmings

    NASA Astrophysics Data System (ADS)

    Solomon, A.

    2012-12-01

    Identifying and diagnosing the mechanism which couples the stratosphere and troposphere during sudden warming events remains a fundamental question of extra-tropical climate variability. In recent years a number of studies have shown that the flux of wave activity out of the troposphere can provide some predictability for extreme vortex events and subsequent influence on the tropospheric circulation (e.g. Polvani 2004). Using the hybrid Lagrangian-Eulerian framework introduced by Nakamura et al. and the ERA-Interim reanalysis, it is demonstrated that the density of pseudomomentum is a better predictor of stratospheric wave-breaking than the Eliassen-Palm flux. Furthermore, the direct relation between this wave activity and the E-P flux explains why the time-integrated flux is a better predictor than the instantaneous flux (Sjoberg 2012). Significant correlations between wave activity aloft and subsequent tropospheric variability underscore the potential for enhanced predictability at intra-seasonal timescales. This new method for visualizing and quantifying the life cycle of sudden warming events reveals the downward propagation of wave activity into the troposphere, difficult to detect using momentum fluxes alone, which may provide the key to unraveling this coupling. comparison of lag-correlations with the zonal mean wind for wave activity (upper) and E-P flux (lower) during sudden warming events. Colors denote magnitude of the correlation with 10mb (white line) predictor timeseries at a given lag (days) relative to the wind at each level. Black contour indicates significance at 99% confidence interval.

  2. Forests: a tool to moderate global warming

    SciTech Connect

    Sedjo, R.A.

    1989-01-01

    Earth's climate may be growing warmer in response to atmospheric accumulation of greenhouse gases, predominantly but not exclusively stemming from human-induced emissions of carbon dioxide (CO/sub 2/) into the atmosphere. Once in the atmosphere, CO/sub 2/ traps heat that would otherwise radiate into space. Each year the Earth's atmosphere takes up approximately 2.9 billion tons of the 4.8 to 5.8 billion tons of carbon that are emitted from various sources. The rest is removed from the atmosphere by natural processes in carbon sinks - places like oceans or forests where carbon is removed from the atmosphere and stored. In addition, changes in land use that have eliminated terrestrial biomass, including tropical forests, have released into the atmosphere the carbon that was captive in the vegetation. Humankind can respond to the prospective global climate change by adapting to the warming, attempting to limit the warming by preventing or mitigating the buildup of atmospheric carbon, or by some combination of the above. Forests can play a critical role in any attempt to mitigate the warming because they are able to capture and store large amounts of carbon from the atmosphere.

  3. Radiative Cooling of Warm Molecular Gas

    NASA Technical Reports Server (NTRS)

    Neufeld, David A.; Kaufman, Michael J.

    1993-01-01

    We consider the radiative cooling of warm (T >= 100 K), fully molecular astrophysical gas by rotational and vibrational transitions of the molecules H2O, CO, and H2. Using an escape probability method to solve for the molecular level populations, we have obtained the cooling rate for each molecule as a function of temperature, density, and an optical depth parameter. A four-parameter expression proves useful in fitting the run of cooling rate with density for any fixed values of the temperature and optical depth parameter. We identify the various cooling mechanisms which are dominant in different regions of the astrophysically relevant parameter space. Given the assumption that water is very abundant in warm regions of the interstellar medium, H2O rotational transitions are found to dominate the cooling of warm interstellar gas over a wide portion of the parameter space considered. While chemical models for the interstellar medium make the strong prediction that water will be produced copiously at temperatures above a few hundred degrees, our assumption of a high water abundance has yet to be tested observationally. The Infrared Space Observatory and the Submillimeter Wave Astronomy Satellite will prove ideal instruments for testing whether water is indeed an important coolant of interstellar and circumstellar gas.

  4. Climate warming will not decrease winter mortality

    NASA Astrophysics Data System (ADS)

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

    2014-03-01

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

  5. The phenology of Arctic Ocean surface warming

    PubMed Central

    Dickinson, Suzanne

    2016-01-01

    Abstract In this work, we explore the seasonal relationships (i.e., the phenology) between sea ice retreat, sea surface temperature (SST), and atmospheric heat fluxes in the Pacific Sector of the Arctic Ocean, using satellite and reanalysis data. We find that where ice retreats early in most years, maximum summertime SSTs are usually warmer, relative to areas with later retreat. For any particular year, we find that anomalously early ice retreat generally leads to anomalously warm SSTs. However, this relationship is weak in the Chukchi Sea, where ocean advection plays a large role. It is also weak where retreat in a particular year happens earlier than usual, but still relatively late in the season, primarily because atmospheric heat fluxes are weak at that time. This result helps to explain the very different ocean warming responses found in two recent years with extreme ice retreat, 2007 and 2012. We also find that the timing of ice retreat impacts the date of maximum SST, owing to a change in the ocean surface buoyancy and momentum forcing that occurs in early August that we term the Late Summer Transition (LST). After the LST, enhanced mixing of the upper ocean leads to cooling of the ocean surface even while atmospheric heat fluxes are still weakly downward. Our results indicate that in the near‐term, earlier ice retreat is likely to cause enhanced ocean surface warming in much of the Arctic Ocean, although not where ice retreat still occurs late in the season. PMID:27867789

  6. Global Warming: Evidence from Satellite Observations

    NASA Technical Reports Server (NTRS)

    Prabhakara, C.; Iacovazzi, R., Jr.; Yoo, J.-M.

    2001-01-01

    Observations made in Channel 2 (53.74 GHz) of the Microwave Sounding Unit (MSU) radiometer, flown on-board sequential, sun-synchronous, polar orbiting NOAA operational satellites, indicate that the mean temperature of the atmosphere over the globe increased during the period 1980 to 1999. In this study we have minimized systematic errors in the time series introduced by the satellite orbital drift in an objective manner. This is done with the help the onboard warm black body temperature, which is used in the calibration of the MSU radiometer. The corrected MSU Channel 2 observations of the NOAA satellite series reveal that the vertically weighted global mean temperature of the atmosphere, with a peak weight near the mid-troposphere, warmed at the rate of 0.13 K per decade (with an uncertainty of 0.05 K per decade) during 1980 to 1999. The global warming deduced from conventional meteorological data that have been corrected for urbanization effects agrees reasonably with this satellite deuced result.

  7. Seaweed communities in retreat from ocean warming.

    PubMed

    Wernberg, Thomas; Russell, Bayden D; Thomsen, Mads S; Gurgel, C Frederico D; Bradshaw, Corey J A; Poloczanska, Elvira S; Connell, Sean D

    2011-11-08

    In recent decades, global climate change [1] has caused profound biological changes across the planet [2-6]. However, there is a great disparity in the strength of evidence among different ecosystems and between hemispheres: changes on land have been well documented through long-term studies, but similar direct evidence for impacts of warming is virtually absent from the oceans [3, 7], where only a few studies on individual species of intertidal invertebrates, plankton, and commercially important fish in the North Atlantic and North Pacific exist. This disparity of evidence is precarious for biological conservation because of the critical role of the marine realm in regulating the Earth's environmental and ecological functions, and the associated socioeconomic well-being of humans [8]. We interrogated a database of >20,000 herbarium records of macroalgae collected in Australia since the 1940s and documented changes in communities and geographical distribution limits in both the Indian and Pacific Oceans, consistent with rapid warming over the past five decades [9, 10]. We show that continued warming might drive potentially hundreds of species toward and beyond the edge of the Australian continent where sustained retreat is impossible. The potential for global extinctions is profound considering the many endemic seaweeds and seaweed-dependent marine organisms in temperate Australia.

  8. Global Warming: Claims, Science, and Consequences

    NASA Astrophysics Data System (ADS)

    Gould, Laurence I.

    2007-04-01

    Widespread (and seemingly dominant) claims about the dire consequences of anthropogenic global warming (AGW) have been propagated by both scientists and politicians and have been prominently featured by much of the mass media. This talk will examine some of those claims --- such as those made in the popular pro-AGW film, An Inconvenient Truth^1 --- from the perspectives of science^2 and scientific methodology^3. Some of the issues considered will be: What are the major ``greenhouse gases''? To what extent is global warming a result of human influences through an increase of ``greenhouse gases''? Is an increase in (1) global temperature and (2) carbon dioxide bad/good? What are some meanings that can be given to the term ``consensus'' in science? What are the estimated financial and other costs of governments implementing the Kyoto accords? Links to readings and videos will be given at the conclusion of the talk. ^1Gore, Al, An Inconvenient Truth: The Planetary Emergency of Global Warming and What We Can Do About It -- (Rodale Press, May, 2006). ^2Marlo Lewis, ``A Skeptic's Guide to An Inconvenient Truth'' http://www.cei.org/pages/aitresponse-book.cfm ^3Aaron Wildavsky, But Is It True? A Citizen's Guide to Environmental Health and Safety Issues (Harvard University Press, 1995), Intro. and Chap. 11. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.NES07.C1.6

  9. Warm-up and performance in competitive swimming.

    PubMed

    Neiva, Henrique P; Marques, Mário C; Barbosa, Tiago M; Izquierdo, Mikel; Marinho, Daniel A

    2014-03-01

    Warm-up before physical activity is commonly accepted to be fundamental, and any priming practices are usually thought to optimize performance. However, specifically in swimming, studies on the effects of warm-up are scarce, which may be due to the swimming pool environment, which has a high temperature and humidity, and to the complexity of warm-up procedures. The purpose of this study is to review and summarize the different studies on how warming up affects swimming performance, and to develop recommendations for improving the efficiency of warm-up before competition. Most of the main proposed effects of warm-up, such as elevated core and muscular temperatures, increased blood flow and oxygen delivery to muscle cells and higher efficiency of muscle contractions, support the hypothesis that warm-up enhances performance. However, while many researchers have reported improvements in performance after warm-up, others have found no benefits to warm-up. This lack of consensus emphasizes the need to evaluate the real effects of warm-up and optimize its design. Little is known about the effectiveness of warm-up in competitive swimming, and the variety of warm-up methods and swimming events studied makes it difficult to compare the published conclusions about the role of warm-up in swimming. Recent findings have shown that warm-up has a positive effect on the swimmer's performance, especially for distances greater than 200 m. We recommend that swimmers warm-up for a relatively moderate distance (between 1,000 and 1,500 m) with a proper intensity (a brief approach to race pace velocity) and recovery time sufficient to prevent the early onset of fatigue and to allow the restoration of energy reserves (8-20 min).

  10. Arctic Warming Signals from Satellite Observations

    NASA Technical Reports Server (NTRS)

    Comiso, Josefino C.

    2005-01-01

    Global warming signals are expected to be amplified in the Arctic primarily because of ice-albedo feedback associated with the high reflectivity of ice and snow that blankets much of the region. The Arctic had been a poorly explored territory basically because of its general inaccessibility on account of extremely harsh weather conditions and the dominant presence of thick perennial ice in the region. The advent of satellite remote sensing systems since the 1960s, however, enabled the acquisition of synoptic data that depict in good spatial detail the temporal changes of many Arctic surface parameters. Among the surface parameters that have been studied using space based systems are surface temperature, sea ice concentration, snow cover, surface albedo and phytoplankton concentration. Associated atmospheric parameters, such as cloud cover, temperature profile, ozone concentration, and aerosol have also been derived. Recent observational and phenomenological studies have indeed revealed progressively changing conditions in the Arctic during the last few decades (e g , Walsh et al. 1996; Serreze et al 2000; Comiso and Parkinson 2004). The changes included declines in the extent and area of surfaces covered by sea ice and snow, increases in melt area over the Greenland ice sheets, thawing of the permafrost, warming in the troposphere, and retreat of the glaciers. These observations are consistent with the observed global warming that has been associated with the increasing concentration of greenhouse gases in the atmosphere (Karl and Trenberth 2003) and confirmed by modeling studies (Holland and Bitz, 2003). The Arctic system, however, is still not well understood complicated by a largely fluctuating wind circulation and atmospheric conditions (Proshutinsky and Johnson 1997) and controlled by what is now known as the Arctic Oscillation (AO) which provides a measure of the strength of atmospheric activities in the region (Thompson and Wallace 1998). Meanwhile, the

  11. Can cirrus clouds warm early Mars?

    NASA Astrophysics Data System (ADS)

    Ramirez, R. M.

    2015-12-01

    The presence of the ancient valley networks on Mars indicates a climate 3.8 Ga that was warm enough to allow substantial liquid water to flow on the martian surface for extended periods of time. However, the origin of these enigmatic features is hotly debated and discussion of their formation has been focused on how warm such a climate may have been and for how long. Recent warm and wet solutions using single-column radiative convective models involve supplementing CO2-H2O atmospheres with other greenhouse gases, such as H2 (i.e. Ramirez et al., 2014; Batalha et al., 2015). An interesting recent proposal, using the CAM 3-D General Circulation model, argues that global cirrus cloud decks in CO2-H2O atmospheres with at least 0.25 bar of CO2 , consisting of 10-micron (and larger) sized particles, could have generated the above-freezing temperatures required to explain the early martian surface geology (Urata and Toon, 2013). Here, we use our single-column radiative convective climate model to check these 3-D results and analyze the likelihood that such warm atmospheres, with mean surface pressures of up to 3 bar, could have supported cirrus cloud decks at full and fractional cloud cover for sufficiently long durations to form the ancient valleys. Our results indicate that cirrus cloud decks could have provided the mean surface temperatures required, but only if cloud cover approaches 100%, in agreement with Urata and Toon (2013). However, even should cirrus cloud coverage approach 100%, we show that such atmospheres are likely to have been too short-lived to produce the volumes of water required to carve the ancient valleys. At more realistic early Mars cloud fractions (~50%, Forget et al., 2013), cirrus clouds do not provide the required warming. Batalha, N., Domagal-Goldman, S. D., Ramirez, R.M., & Kasting, J. F., 2015. Icarus, 258, 337-349. Forget, F., Wordsworth, R., Millour, E., Madeleine, J. B., Kerber, L., Leconte, J., ... & Haberle, R. M., 2013. Icarus, 222

  12. Mechanisms of the warm-up phenomenon.

    PubMed

    Tomai, F; Crea, F; Danesi, A; Perino, M; Gaspardone, A; Ghini, A S; Cascarano, M T; Chiariello, L; Gioffrè, P A

    1996-07-01

    The warm-up phenomenon, described in patients with coronary artery disease, refers to the improved performance following a first exercise test. The aim of this study was to investigate the causes of the warm-up phenomenon. Fifteen patients with coronary artery disease and positive exercise test were enrolled. Patients were off treatment throughout the study. They underwent two consecutive treadmill exercise tests according to the Bruce protocol, with a recovery period of 10 min to re-establish baseline conditions. A third exercise test was then performed 2 h later. Before the onset of ischaemia, the rate-pressure product for a similar degree of workload was similar during the first and second exercise test, while it was lower during the third test (P < 0.05). Time to 1.5 mm ST-segment depression during the second and third exercise test was greater than during the first test (454 +/- 133 and 410 +/- 161 vs 354 +/- 127 s, P < 0.01, respectively). Similarly, the time to anginal pain onset was increased during the second and third exercise tests, compared to the first test (356 +/- 208 and 310 +/- 203 vs 257 +/- 204 s, P < 0.01, respectively). In contrast, rate-pressure product at 1.5 mm ST-segment depression during the second test was higher than that during the first test (232 +/- 47 vs 210 +/- 39 beats.min-1.mmHg.10(2), P < 0.01), while in the third test it was similar to that during the first (209 +/- 43 beats.min-1.mmHg.10(2), P = ns). The warm-up phenomenon observed a few minutes after exercise is characterized by an increase of both time to ischaemia and ischaemic threshold; this adaptation to ischaemia may be due to an improvement of myocardial perfusion or to preconditioning. Conversely, the warm-up phenomenon observed a few hours after repeated exercise is characterized by an increase of time to ischaemia but not of ischaemic threshold and is caused by a slower increase of cardiac workload. Thus, the mechanisms of the warm-up phenomenon may be different

  13. Wind changes above warm Agulhas Current eddies

    NASA Astrophysics Data System (ADS)

    Rouault, M.; Verley, P.; Backeberg, B.

    2016-04-01

    Sea surface temperature (SST) estimated from the Advanced Microwave Scanning Radiometer E onboard the Aqua satellite and altimetry-derived sea level anomalies are used south of the Agulhas Current to identify warm-core mesoscale eddies presenting a distinct SST perturbation greater than to 1 °C to the surrounding ocean. The analysis of twice daily instantaneous charts of equivalent stability-neutral wind speed estimates from the SeaWinds scatterometer onboard the QuikScat satellite collocated with SST for six identified eddies shows stronger wind speed above the warm eddies than the surrounding water in all wind directions, if averaged over the lifespan of the eddies, as was found in previous studies. However, only half of the cases showed higher wind speeds above the eddies at the instantaneous scale; 20 % of cases had incomplete data due to partial global coverage by the scatterometer for one path. For cases where the wind is stronger above warm eddies, there is no relationship between the increase in surface wind speed and the SST perturbation, but we do find a linear relationship between the decrease in wind speed from the centre to the border of the eddy downstream and the SST perturbation. SST perturbations range from 1 to 6 °C for a mean eddy SST of 15.9 °C and mean SST perturbation of 2.65 °C. The diameter of the eddies range from 100 to 250 km. Mean background wind speed is about 12 m s-1 (mostly southwesterly to northwesterly) and ranging mainly from 4 to 16 m s-1. The mean wind increase is about 15 %, which corresponds to 1.8 m s-1. A wind speed increase of 4 to 7 m s-1 above warm eddies is not uncommon. Cases where the wind did not increase above the eddies or did not decrease downstream had higher wind speeds and occurred during a cold front associated with intense cyclonic low-pressure systems, suggesting certain synoptic conditions need to be met to allow for the development of wind speed anomalies over warm-core ocean eddies. In many cases

  14. Experimental winter warming modifies thermal performance and primes acorn ants for warm weather.

    PubMed

    MacLean, Heidi J; Penick, Clint A; Dunn, Robert R; Diamond, Sarah E

    2017-07-01

    The frequency of warm winter days is increasing under global climate change, but how organisms respond to warmer winters is not well understood. Most studies focus on growing season responses to warming. Locomotor performance is often highly sensitive to temperature, and can determine fitness outcomes through a variety of mechanisms including resource acquisition and predator escape. As a consequence, locomotor performance, and its impacts on fitness, may be strongly affected by winter warming in winter-active species. Here we use the acorn ant, Temnothorax curvispinosus, to explore how thermal performance (temperature-driven plasticity) in running speed is influenced by experimental winter warming of 3-5°C above ambient in a field setting. We used running speed as a measure of performance as it is a common locomotor trait that influences acquisition of nest sites and food in acorn ants. Experimental winter warming significantly altered thermal performance for running speed at high (26 and 36°C) but not low test temperatures (6 and 16°C). Although we saw little differentiation in thermal performance at cooler test temperatures, we saw a marked increase in running speed at the hotter test temperatures for ants that experienced warmer winters compared with those that experienced cooler winters. Our results provide evidence that overwintering temperatures can substantially influence organismal performance, and suggest that we cannot ignore overwintering effects when forecasting organismal responses to environmental changes in temperature. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Why tropical forest lizards are vulnerable to climate warming

    PubMed Central

    Huey, Raymond B.; Deutsch, Curtis A.; Tewksbury, Joshua J.; Vitt, Laurie J.; Hertz, Paul E.; Álvarez Pérez, Héctor J.; Garland, Theodore

    2009-01-01

    Biological impacts of climate warming are predicted to increase with latitude, paralleling increases in warming. However, the magnitude of impacts depends not only on the degree of warming but also on the number of species at risk, their physiological sensitivity to warming and their options for behavioural and physiological compensation. Lizards are useful for evaluating risks of warming because their thermal biology is well studied. We conducted macrophysiological analyses of diurnal lizards from diverse latitudes plus focal species analyses of Puerto Rican Anolis and Sphaerodactyus. Although tropical lowland lizards live in environments that are warm all year, macrophysiological analyses indicate that some tropical lineages (thermoconformers that live in forests) are active at low body temperature and are intolerant of warm temperatures. Focal species analyses show that some tropical forest lizards were already experiencing stressful body temperatures in summer when studied several decades ago. Simulations suggest that warming will not only further depress their physiological performance in summer, but will also enable warm-adapted, open-habitat competitors and predators to invade forests. Forest lizards are key components of tropical ecosystems, but appear vulnerable to the cascading physiological and ecological effects of climate warming, even though rates of tropical warming may be relatively low. PMID:19324762

  16. Deep time evidence for climate sensitivity increase with warming

    NASA Astrophysics Data System (ADS)

    Shaffer, Gary; Huber, Matthew; Rondanelli, Roberto; Pepke Pedersen, Jens Olaf

    2016-06-01

    Future global warming from anthropogenic greenhouse gas emissions will depend on climate feedbacks, the effect of which is expressed by climate sensitivity, the warming for a doubling of atmospheric CO2 content. It is not clear how feedbacks, sensitivity, and temperature will evolve in our warming world, but past warming events may provide insight. Here we employ paleoreconstructions and new climate-carbon model simulations in a novel framework to explore a wide scenario range for the Paleocene-Eocene Thermal Maximum (PETM) carbon release and global warming event 55.8 Ma ago, a possible future warming analogue. We obtain constrained estimates of CO2 and climate sensitivity before and during the PETM and of the PETM carbon input amount and nature. Sensitivity increased from 3.3-5.6 to 3.7-6.5 K (Kelvin) into the PETM. When taken together with Last Glacial Maximum and modern estimates, this result indicates climate sensitivity increase with global warming.

  17. Global warming 2007. An update to global warming: the balance of evidence and its policy implications.

    PubMed

    Keller, Charles F

    2007-03-09

    In the four years since my original review (Keller[25]; hereafter referred to as CFK03), research has clarified and strengthened our understanding of how humans are warming the planet. So many of the details highlighted in the IPCC's Third Assessment Report[21] and in CFK03 have been resolved that I expect many to be a bit overwhelmed, and I hope that, by treating just the most significant aspects of the research, this update may provide a road map through the expected maze of new information. In particular, while most of CFK03 remains current, there are important items that have changed: Most notable is the resolution of the conundrum that mid-tropospheric warming did not seem to match surface warming. Both satellite and radiosonde (balloon-borne sensors) data reduction showed little warming in the middle troposphere (4-8 km altitude). In the CFK03 I discussed potential solutions to this problem, but at that time there was no clear resolution. This problem has now been solved, and the middle troposphere is seen to be warming apace with the surface. There have also been advances in determinations of temperatures over the past 1,000 years showing a cooler Little Ice Age (LIA) but essentially the same warming during medieval times (not as large as recent warming). The recent uproar over the so-called "hockey stick" temperature determination is much overblown since at least seven other groups have made relatively independent determinations of northern hemisphere temperatures over the same time period and derived essentially the same results. They differ on how cold the LIA was but essentially agree with the Mann's hockey stick result that the Medieval Warm Period was not as warm as the last 25 years. The question of the sun's influence on climate continues to generate controversy. It appears there is a growing consensus that, while the sun was a major factor in earlier temperature variations, it is incapable of having caused observed warming in the past quarter

  18. Simulation of future global warming scenarios in rice paddies with an open-field warming facility

    PubMed Central

    2011-01-01

    To simulate expected future global warming, hexagonal arrays of infrared heaters have previously been used to warm open-field canopies of upland crops such as wheat. Through the use of concrete-anchored posts, improved software, overhead wires, extensive grounding, and monitoring with a thermal camera, the technology was safely and reliably extended to paddy rice fields. The system maintained canopy temperature increases within 0.5°C of daytime and nighttime set-point differences of 1.3 and 2.7°C 67% of the time. PMID:22145582

  19. Simulation of future global warming scenarios in rice paddies with an open-field warming facility.

    PubMed

    Rehmani, Muhammad Ishaq Asif; Zhang, Jingqi; Li, Ganghua; Ata-Ul-Karim, Syed Tahir; Wang, Shaohua; Kimball, Bruce A; Yan, Chuan; Liu, Zhenghui; Ding, Yanfeng

    2011-12-06

    To simulate expected future global warming, hexagonal arrays of infrared heaters have previously been used to warm open-field canopies of upland crops such as wheat. Through the use of concrete-anchored posts, improved software, overhead wires, extensive grounding, and monitoring with a thermal camera, the technology was safely and reliably extended to paddy rice fields. The system maintained canopy temperature increases within 0.5°C of daytime and nighttime set-point differences of 1.3 and 2.7°C 67% of the time.

  20. Punishments and Prizes for Explaining Global Warming

    NASA Astrophysics Data System (ADS)

    Somerville, R. C.

    2006-12-01

    Some few gifted scientists, the late Carl Sagan being an iconic example, are superbly skilled at communicating science clearly and compellingly to non-scientists. Most scientists, however, have serious shortcomings as communicators. The common failings include being verbose, addicted to jargon, caveat- obsessed and focused on details. In addition, it is far easier for a scientist to scoff at the scientific illiteracy of modern society than to work at understanding the viewpoints and concerns of journalists, policymakers and the public. Obstacles await even those scientists with the desire and the talent to communicate science well. Peer pressure and career disincentives can act as powerful deterrents, discouraging especially younger scientists from spending time on non-traditional activities. Scientists often lack mentors and role models to help them develop skills in science communication. Journalists also face real difficulties in getting science stories approved by editors and other gatekeepers. Climate change science brings its own problems in communication. The science itself is unusually wide- ranging and complex. The contentious policies and politics of dealing with global warming are difficult to disentangle from the science. Misinformation and disinformation about climate change are widespread. Intimidation and censorship of scientists by some employers is a serious problem. Polls show that global warming ranks low on the public's list of important issues. Despite all the obstacles, communicating climate change science well is critically important today. It is an art that can be learned and that brings its own rewards and satisfactions. Academic institutions and research funding agencies increasingly value outreach by scientists, and they provide resources to facilitate it. Society needs scientists who can clearly and authoritatively explain the science of global warming and its implications, while remaining objective and policy-neutral. This need will

  1. Multishock Compression Properties of Warm Dense Argon

    PubMed Central

    Zheng, Jun; Chen, Qifeng; Yunjun, Gu; Li, Zhiguo; Shen, Zhijun

    2015-01-01

    Warm dense argon was generated by a shock reverberation technique. The diagnostics of warm dense argon were performed by a multichannel optical pyrometer and a velocity interferometer system. The equations of state in the pressure-density range of 20–150 GPa and 1.9–5.3 g/cm3 from the first- to fourth-shock compression were presented. The single-shock temperatures in the range of 17.2–23.4 kK were obtained from the spectral radiance. Experimental results indicates that multiple shock-compression ratio (ηi = ρi/ρ0) is greatly enhanced from 3.3 to 8.8, where ρ0 is the initial density of argon and ρi (i = 1, 2, 3, 4) is the compressed density from first to fourth shock, respectively. For the relative compression ratio (ηi’ = ρi/ρi-1), an interesting finding is that a turning point occurs at the second shocked states under the conditions of different experiments, and ηi’ increases with pressure in lower density regime and reversely decreases with pressure in higher density regime. The evolution of the compression ratio is controlled by the excitation of internal degrees of freedom, which increase the compression, and by the interaction effects between particles that reduce it. A temperature-density plot shows that current multishock compression states of argon have distributed into warm dense regime. PMID:26515505

  2. Indentifying the Molecular Origin of Global Warming

    NASA Astrophysics Data System (ADS)

    Bera, P. P.; Lee, T. J.; Francisco, J.

    2009-12-01

    Indentifying the Molecular Origin of Global Warming Partha P. Bera, Joseph S. Francisco and Timothy J. Lee NASA Ames Research Center, Space Science and Astrobiology Division, Moffett Field, California 94035, and Department of Chemistry and Department of Earth and Atmospheric Sciences, Purdue University, West Lafayette, Indiana 47907-1393 Abstract The physical characteristics of greenhouse gases (GHGs) have been investigated to assess which properties are most important in determining the radiative efficiency of a GHG. Chlorofluorcarbons (CFCs), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), hydrofluoroethers, fluoroethers, nitrogen fluorides, and various other known atmospheric trace molecules have been included in this study. Compounds containing the halogens F or Cl have in common very polar X-F or X-Cl bonds, particularly the X-F bonds. It is shown that as more F atoms bond to the same central atom, the bond dipoles become larger as a result of the central carbon atom becoming more positive. This leads to a linear increase in the total or integrated X-F bond dipole derivatives for the molecule, which leads to a non-linear (quadratic) increase in infrared (IR) intensity. Moreover, virtually all of the X-F bond stretches occur in the atmospheric IR window as opposed to X-H stretches, which do not occur in the atmospheric window. It is concluded that molecules possessing several F atoms will always have a large radiative forcing parameter in the calculation of their global warming potential. Some of the implications for global warming and climate change and a new design strategy for more environmentally friendly industrial materials from a molecular quantum chemistry perspective will be discussed.

  3. Post-Babesiosis Warm Autoimmune Hemolytic Anemia.

    PubMed

    Woolley, Ann E; Montgomery, Mary W; Savage, William J; Achebe, Maureen O; Dunford, Kathleen; Villeda, Sarah; Maguire, James H; Marty, Francisco M

    2017-03-09

    Background Babesiosis, a tickborne zoonotic disease caused by intraerythrocytic protozoa of the genus babesia, is characterized by nonimmune hemolytic anemia that resolves with antimicrobial treatment and clearance of parasitemia. The development of warm-antibody autoimmune hemolytic anemia (also known as warm autoimmune hemolytic anemia [WAHA]) in patients with babesiosis has not previously been well described. Methods After the observation of sporadic cases of WAHA that occurred after treatment of patients for babesiosis, we conducted a retrospective cohort study of all the patients with babesiosis who were cared for at our center from January 2009 through June 2016. Data on covariates of interest were extracted from the medical records, including any hematologic complications that occurred within 3 months after the diagnosis and treatment of babesiosis. Results A total of 86 patients received a diagnosis of babesiosis during the 7.5-year study period; 18 of these patients were asplenic. WAHA developed in 6 patients 2 to 4 weeks after the diagnosis of babesiosis, by which time all the patients had had clinical and laboratory responses to antimicrobial treatment of babesiosis, including clearance of Babesia microti parasitemia. All 6 patients were asplenic (P<0.001) and had positive direct antiglobulin tests for IgG and complement component 3; warm autoantibodies were identified in all these patients. No alternative explanation for clinical hemolysis was found. WAHA required immunosuppressive treatment in 4 of the 6 patients. Conclusions We documented post-babesiosis WAHA in patients who did not have a history of autoimmunity; asplenic patients appeared to be particularly at risk.

  4. Warm inflation in presence of magnetic fields

    SciTech Connect

    Piccinelli, Gabriella; Ayala, Alejandro; Mizher, Ana Julia

    2013-07-23

    We present preliminary results on the possible effects that primordial magnetic fields can have for a warm inflation scenario, based on global supersymmetry, with a new-inflation-type potential. This work is motivated by two considerations: first, magnetic fields seem to be present in the universe on all scales which rises de possibility that they could also permeate the early universe; second, the recent emergence of inflationary models where the inflaton is not assumed to be isolated but instead it is taken as an interacting field, even during the inflationary expansion. The effects of magnetic fields are included resorting to Schwinger's proper time method.

  5. Global warming and carbon dioxide through sciences.

    PubMed

    Florides, Georgios A; Christodoulides, Paul

    2009-02-01

    Increased atmospheric CO(2)-concentration is widely being considered as the main driving factor that causes the phenomenon of global warming. This paper attempts to shed more light on the role of atmospheric CO(2) in relation to temperature-increase and, more generally, in relation to Earth's life through the geological aeons, based on a review-assessment of existing related studies. It is pointed out that there has been a debate on the accuracy of temperature reconstructions as well as on the exact impact that CO(2) has on global warming. Moreover, using three independent sets of data (collected from ice-cores and chemistry) we perform a specific regression analysis which concludes that forecasts about the correlation between CO(2)-concentration and temperature rely heavily on the choice of data used, and one cannot be positive that indeed such a correlation exists (for chemistry data) or even, if existing (for ice-cores data), whether it leads to a "severe" or a "gentle" global warming. A very recent development on the greenhouse phenomenon is a validated adiabatic model, based on laws of physics, forecasting a maximum temperature-increase of 0.01-0.03 degrees C for a value doubling the present concentration of atmospheric CO(2). Through a further review of related studies and facts from disciplines like biology and geology, where CO(2)-change is viewed from a different perspective, it is suggested that CO(2)-change is not necessarily always a negative factor for the environment. In fact it is shown that CO(2)-increase has stimulated the growth of plants, while the CO(2)-change history has altered the physiology of plants. Moreover, data from palaeoclimatology show that the CO(2)-content in the atmosphere is at a minimum in this geological aeon. Finally it is stressed that the understanding of the functioning of Earth's complex climate system (especially for water, solar radiation and so forth) is still poor and, hence, scientific knowledge is not at a level to

  6. Atom Interferometry in a Warm Vapor

    DOE PAGES

    Biedermann, G. W.; McGuinness, H. J.; Rakholia, A. V.; ...

    2017-04-17

    Here, we demonstrate matter-wave interference in a warm vapor of rubidium atoms. Established approaches to light-pulse atom interferometry rely on laser cooling to concentrate a large ensemble of atoms into a velocity class resonant with the atom optical light pulse. In our experiment, we show that clear interference signals may be obtained without laser cooling. This effect relies on the Doppler selectivity of the atom interferometer resonance. Lastly, this interferometer may be configured to measure accelerations, and we demonstrate that multiple interferometers may be operated simultaneously by addressing multiple velocity classes.

  7. Climate Models have Accurately Predicted Global Warming

    NASA Astrophysics Data System (ADS)

    Nuccitelli, D. A.

    2016-12-01

    Climate model projections of global temperature changes over the past five decades have proven remarkably accurate, and yet the myth that climate models are inaccurate or unreliable has formed the basis of many arguments denying anthropogenic global warming and the risks it poses to the climate system. Here we compare average global temperature predictions made by both mainstream climate scientists using climate models, and by contrarians using less physically-based methods. We also explore the basis of the myth by examining specific arguments against climate model accuracy and their common characteristics of science denial.

  8. Scientists' Views about Attribution of Global Warming

    NASA Astrophysics Data System (ADS)

    Verheggen, Bart; Strengers, Bart; Cook, John; van Dorland, Rob; Vringer, Kees; Peters, Jeroen; Visser, Hans; Meyer, Leo

    2015-04-01

    What do scientists think? That is an important question when engaging in science communication, in which an attempt is made to communicate the scientific understanding to a lay audience. To address this question we undertook a large and detailed survey among scientists studying various aspects of climate change , dubbed "perhaps the most thorough survey of climate scientists ever" by well-known climate scientist and science communicator Gavin Schmidt. Among more than 1800 respondents we found widespread agreement that global warming is predominantly caused by human greenhouse gases. This consensus strengthens with increased expertise, as defined by the number of self-reported articles in the peer-reviewed literature. 90% of respondents with more than 10 climate-related peer-reviewed publications (about half of all respondents), agreed that anthropogenic greenhouse gases are the dominant cause of recent global warming, i.e. having contributed more than half of the observed warming. With this survey we specified what the consensus position entails with much greater specificity than previous studies. The relevance of this consensus for science communication will be discussed. Another important result from our survey is that the main attribution statement in IPCC's fourth assessment report (AR4) may lead to an underestimate of the greenhouse gas contribution to warming, because it implicitly includes the lesser known masking effect of cooling aerosols. This shows the importance of the exact wording in high-profile reports such as those from IPCC in how the statement is perceived, even by fellow scientists. The phrasing was improved in the most recent assessment report (AR5). Respondents who characterized the human influence on climate as insignificant, reported having the most frequent media coverage regarding their views on climate change. This shows that contrarian opinions are amplified in the media in relation to their prevalence in the scientific community. This

  9. Automatic filament warm-up controller

    NASA Technical Reports Server (NTRS)

    Mccluskey, J.; Daeges, J.

    1979-01-01

    As part of the unattended operations objective of the Deep Space Network deep space stations, this filament controller serves as a step between manual operation of the station and complete computer control. Formerly, the operator was required to devote five to fifteen minutes of his time just to properly warm up the filaments on the klystrons of the high power transmitters. The filament controller reduces the operator's duty to a one-step command and is future-compatible with various forms of computer control.

  10. Warming Early Mars With CH4

    NASA Astrophysics Data System (ADS)

    Justh, H. L.; Kasting, J. F.

    2002-12-01

    The nature of the ancient climate of Mars remains one of the fundamental unresolved problems in martian research. While the present environment is hostile to life, images from the Mariner, Viking and Mars Global Surveyor missions, have shown geologic features on the martian surface that seem to indicate an earlier period of hydrologic activity. The fact that ancient valley networks and degraded craters have been seen on the martian surface indicates that the early martian climate may have been more Earth-like, with a warmer surface temperature. The presence of liquid water would require a greenhouse effect much larger than needed at present, as the solar constant, S0, was 25% lower 3.8 billion years ago when the channels are thought to have formed (1,2). Previous calculations have shown that gaseous CO2 and H2O alone could not have warmed the martian surface to the temperature needed to account for the presence of liquid water (3). It has been hypothesized that a CO2-H2O atmosphere could keep early Mars warm if it was filled with CO2 ice clouds in the upper martian troposphere (4). Obtaining mean martian surface temperatures above 273 K would require nearly 100% cloud cover, a condition that is unrealistic for condensation clouds on early Mars. Any reduction in cloud cover makes it difficult to achieve warm martian surface temperatures except at high pressures and CO2 clouds could cool the martian surface if they were low and optically thick (5). CO2 and CH4 have been suggested as important greenhouse gases on the early Earth. Our research focuses on the effects of increased concentrations of atmospheric greenhouse gases on the surface temperature of early Mars, with emphasis on the reduced greenhouse gas, CH4. To investigate the possible warming effect of CH4, we modified a one-dimensional, radiative-convective climate model used in previous studies of the early martian climate (5). New cloud-free temperature profiles for various surface pressures and CH4 mixing

  11. Anthropogenic global warming threatens world cultural heritage

    NASA Astrophysics Data System (ADS)

    Cazenave, Anny

    2014-05-01

    Numerous cultural sites of the United Nations Educational, Scientific and Cultural Organization (UNESCO) world cultural Heritage are located in low-lying coastal regions. Because of anthropogenic global warming and induced sea level rise, many of these sites will be partially or totally flooded in the coming centuries/millennia. This is shown in a recent study by Marzeion and Levermann (2014 Environ. Res. Lett. 9 034001). Projecting future sea level rise and associated regional variability, these authors investigate which sites will be at risk. Because UNESCO cultural sites represent the common heritage of human beings and reflect the Earth and humanity history, they need to be protected for future generations.

  12. Does coral bleaching mean global warming

    SciTech Connect

    Miller, J.A.

    1991-02-01

    This article discusses the implications of global warming on the marine ecosystems. In recent hearings of the US Senate Committee on Commerce, Science and Transportation, plans were made to introduce legislation for control of greenhouse-gas emissions, conservation of biological diversity, forest conservation, world population planning, sustainable economic development , increased fuel efficiency, and increased research into Earth-system processes. Research is required to ascertain the meaning of coral bleaching, which is the mass expulsion of symbiotic algae, called zooxanthellae, which gives the coral its color. Many scientists think that the death of the algae is an early indicator for massive destruction of the marine ecosystem.

  13. Spherical warm shield design for infrared imaging systems

    NASA Astrophysics Data System (ADS)

    Tian, Qijie; Chang, Songtao; He, Fengyun; Li, Zhou; Qiao, Yanfeng

    2017-09-01

    The F-number matching is the primary means to suppress stray radiation for infrared imaging systems. However, it is difficult to achieve exact F-number matching, owing to the restriction from detectors, or multiple F-number design. Hence, an additional shield is required to block the certain thermal radiation. Typical shield is called flat warm shield, which is flat and operates at room temperature. For flat warm shield, it cannot suppress stray radiation while achieving F-number matching. To overcome the restriction, a spherical reflective warm shield is required. First of all, the detailed theory of spherical warm shield design is developed on basis of the principle that stray radiation cannot directly reach the infrared focal plane array. According to the theory developed above, a polished spherical warm shield, whose radius is 18 mm, is designed to match an F/2 infrared detector with an F/4 infrared imaging system. Then, the performance and alignment errors of the designed spherical warm shield are analyzed by simulation. Finally, a contrast experiment between the designed spherical warm shield and two differently processed flat warm shields is performed in a chamber with controllable inside temperatures. The experimental results indicate that the designed spherical warm shield cannot only achieve F-number matching but suppress stray radiation sufficiently. Besides, it is demonstrated that the theory of spherical warm shield design developed in this paper is valid and can be employed by arbitrary infrared imaging systems.

  14. Soil crusts to warm the planet

    NASA Astrophysics Data System (ADS)

    Garcia-Pichel, Ferran; Couradeau, Estelle; Karaoz, Ulas; da Rocha Ulisses, Nunes; Lim Hsiao, Chiem; Northen, Trent; Brodie, Eoin

    2016-04-01

    Soil surface temperature, an important driver of terrestrial biogeochemical processes, depends strongly on soil albedo, which can be significantly modified by factors such as plant cover. In sparsely vegetated lands, the soil surface can also be colonized by photosynthetic microbes that build biocrust communities. We used concurrent physical, biochemical and microbiological analyses to show that mature biocrusts can increase surface soil temperature by as much as 10 °C through the accumulation of large quantities of a secondary metabolite, the microbial sunscreen scytonemin, produced by a group of late-successional cyanobacteria. Scytonemin accumulation decreases soil albedo significantly. Such localized warming had apparent and immediate consequences for the crust soil microbiome, inducing the replacement of thermosensitive bacterial species with more thermotolerant forms. These results reveal that not only vegetation but also microorganisms are a factor in modifying terrestrial albedo, potentially impacting biosphere feedbacks on past and future climate, and call for a direct assessment of such effects at larger scales. Based on estimates of the global biomass of cyanobacteria in soil biocrusts, one can easily calculate that there must currently exist about 15 million metric tons of scytonemin at work, warming soil surfaces worldwide

  15. Identifying the Molecular Origin of Global Warming

    NASA Technical Reports Server (NTRS)

    Bera, Partha P.; Francisco, Joseph S.; Lee, Timothy J.

    2009-01-01

    We have investigated the physical characteristics of greenhouse gases (GHGs) to assess which properties are most important in determining the efficiency of a GHG. Chlorofluorcarbons (CFCs), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), nitrogen fluorides, and various other known atmospheric trace molecules have been included in this study. Compounds containing the halogens F or Cl have in common very polar X-F or X-Cl bonds, particularly the X-F bonds. It is shown that as more F atoms bond to the same central atom, the bond dipoles become larger as a result of the central atom becoming more positive. This leads to a linear increase in the total or integrated XF bond dipole derivatives for the molecule, which leads to a non-linear (quadratic) increase in infrared (IR) intensity. Moreover, virtually all of the X-F bond stretches occur in the atmospheric IR window as opposed to X-H stretches, which do not occur in the atmospheric window. It is concluded that molecules possessing several F atoms will always have a large radiative forcing parameter in the calculation of their global warming potential. Some of the implications for global warming and climate change are discussed.

  16. Environmental refugees in a globally warmed world

    SciTech Connect

    Myers, N.

    1993-12-01

    This paper examines the complex problem of environmental refugees as among the most serious of all the effects of global warming. Shoreline erosion, coastal flooding, and agricultural disruption from drought, soil erosion and desertification are factors now and in the future in creating a group of environmental refugees. Estimates are that at least 10 million such refugees exist today. A preliminary analysis is presented here as a first attempt to understand the full character and extent of the problem. Countries with large delta and coastal areas and large populations are at particular risk from sea-level rise of as little as .5 - 1 meter, compounded by storm surge and salt water intrusions. Bangladesh, Egypt, China, and India are discussed in detail along with Island states at risk. Other global warming effects such as shifts in monsoon systems and severe and persistent droughts make agriculture particularly vulnerable. Lack of soil moisture is during the growing season will probably be the primary problem. Additional and compounding environmental problems are discussed, and an overview of the economic, sociocultural and political consequences is given. 96 refs., 1 tab.

  17. Climatic warming disrupts recurrent Alpine insect outbreaks

    PubMed Central

    Johnson, Derek M.; Büntgen, Ulf; Frank, David C.; Kausrud, Kyrre; Haynes, Kyle J.; Liebhold, Andrew M.; Esper, Jan; Stenseth, Nils Chr.

    2010-01-01

    Climate change has been identified as a causal factor for diverse ecological changes worldwide. Warming trends over the last couple of decades have coincided with the collapse of long-term population cycles in a broad range of taxa, although causal mechanisms are not well-understood. Larch budmoth (LBM) population dynamics across the European Alps, a classic example of regular outbreaks, inexplicably changed sometime during the 1980s after 1,200 y of nearly uninterrupted periodic outbreak cycles. Herein, analysis of perhaps the most extensive spatiotemporal dataset of population dynamics and reconstructed Alpine-wide LBM defoliation records reveals elevational shifts in LBM outbreak epicenters that coincide with temperature fluctuations over two centuries. A population model supports the hypothesis that temperature-mediated shifting of the optimal elevation for LBM population growth is the mechanism for elevational epicenter changes. Increases in the optimal elevation for population growth over the warming period of the last century to near the distributional limit of host larch likely dampened population cycles, thereby causing the collapse of a millennium-long outbreak cycle. The threshold-like change in LBM outbreak pattern highlights how interacting species with differential response rates to climate change can result in dramatic ecological changes. PMID:21059922

  18. Global warming and thermohaline circulation stability.

    PubMed

    Wood, Richard A; Vellinga, Michael; Thorpe, Robert

    2003-09-15

    The Atlantic thermohaline circulation (THC) plays an important role in global climate. Theoretical and palaeoclimatic evidence points to the possibility of rapid changes in the strength of the THC, including a possible quasi-permanent shutdown. The climatic impacts of such a shutdown would be severe, including a cooling throughout the Northern Hemisphere, which in some regions is greater in magnitude than the changes expected from global warming in the next 50 years. Other climatic impacts would likely include a severe alteration of rainfall patterns in the tropics, the Indian subcontinent and Europe. Modelling the future behaviour of the THC focuses on two key questions. (i) Is a gradual weakening of the THC likely in response to global warming, and if so by how much? (ii) Are there thresholds beyond which rapid or irreversible changes in the THC are likely? Most projections of the response of the THC to increasing concentrations of greenhouse gases suggest a gradual weakening over the twenty-first century. However, there is a wide variation between different models over the size of the weakening. Rapid or irreversible THC shutdown is considered a low-probability (but high-impact) outcome; however, some climate models of intermediate complexity do show the possibility of such events. The question of the future of the THC is beset with conceptual, modelling and observational uncertainties, but some current and planned projects show promise to make substantial progress in tackling these uncertainties in future.

  19. Warming alters the metabolic balance of ecosystems.

    PubMed

    Yvon-Durocher, Gabriel; Jones, J Iwan; Trimmer, Mark; Woodward, Guy; Montoya, Jose M

    2010-07-12

    The carbon cycle modulates climate change, via the regulation of atmospheric CO(2), and it represents one of the most important services provided by ecosystems. However, considerable uncertainties remain concerning potential feedback between the biota and the climate. In particular, it is unclear how global warming will affect the metabolic balance between the photosynthetic fixation and respiratory release of CO(2) at the ecosystem scale. Here, we present a combination of experimental field data from freshwater mesocosms, and theoretical predictions derived from the metabolic theory of ecology to investigate whether warming will alter the capacity of ecosystems to absorb CO(2). Our manipulative experiment simulated the temperature increases predicted for the end of the century and revealed that ecosystem respiration increased at a faster rate than primary production, reducing carbon sequestration by 13 per cent. These results confirmed our theoretical predictions based on the differential activation energies of these two processes. Using only the activation energies for whole ecosystem photosynthesis and respiration we provide a theoretical prediction that accurately quantified the precise magnitude of the reduction in carbon sequestration observed experimentally. We suggest the combination of whole-ecosystem manipulative experiments and ecological theory is one of the most promising and fruitful research areas to predict the impacts of climate change on key ecosystem services.

  20. Black carbon contribution to global warming

    SciTech Connect

    Chylek, P.; Johnson, B.; Kou, L.; Wong, J.

    1996-12-31

    Before the onset of industrial revolution the only important source of black carbon in the atmosphere was biomass burning. Today, black carbon production is divided between the biomass and fossil fuel burning. Black carbon is a major agent responsible for absorption of solar radiation by atmospheric aerosols. Thus black carbon makes other aerosols less efficient in their role of reflecting solar radiation and cooling the earth-atmosphere system. Black carbon also contributes to the absorption of solar radiation by clouds and snow cover. The authors present the results of black carbon concentrations measurements in the atmosphere, in cloud water, in rain and snow melt water collected during the 1992--1996 time period over the southern Nova Scotia. Their results are put into the global and historical perspective by comparing them with the compilation of past measurements at diverse locations and with their measurements of black carbon concentrations in the Greenland and Antarctic ice cores. Black carbon contribution to the global warming is estimated, and compared to the carbon dioxide warming, using the radiative forcing caused by the black carbon at the top of the atmosphere.

  1. Recent Permafrost Warming in Northwest Canada

    NASA Astrophysics Data System (ADS)

    Burn, C.

    2002-12-01

    Ground temperature records, mostly collected by industry, are available for the Mackenzie delta area and western Arctic coast of Canada from the late 1960s and early 1970s. At Garry Island, the mean annual ground temperature (MAGT) is -6C, 2C warmer than previously. Similar data are available for northern Richards Island, and at the Illisarvik drained lake site, on Richards Island, MAGT in the early 1980s was -7C. At Herschel Island, the MAGT is -8C. There are no prior records from Herschel, but similar sites in the region distant from the Mackenzie River discharge plume previously recorded -9 to -10C. These data point to a relatively rapid response of near-surface permafrost temperatures to regional climate warming, due to the minimal phase change at these relatively cold temperatures in the continuous permafrost zone. In contrast, permafrost temperatures close to 0C in central and southern YT show relatively little response to climate warming due to the large amount of latent heat required for a small increase in ground temperature, and to the cooling achieved in separate winters with little or late snowfall.

  2. Global warming potential impact of bioenergy systems

    NASA Astrophysics Data System (ADS)

    Tonini, D.; Hamelin, L.; Wenzel, H.; Astrup, T.

    2012-10-01

    Reducing dependence on fossil fuels and mitigation of GHG emissions is a main focus in the energy strategy of many Countries. In the case of Demark, for instance, the long-term target of the energy policy is to reach 100% renewable energy system. This can be achieved by drastic reduction of the energy demand, optimization of production/distribution and substitution of fossil fuels with biomasses. However, a large increase in biomass consumption will finally induce conversion of arable and currently cultivated land into fields dedicated to energy crops production determining significant environmental consequences related to land use changes. In this study the global warming potential impact associated with six alternative bioenergy systems based on willow and Miscanthus was assessed by means of life-cycle assessment. The results showed that bioenergy production may generate higher global warming impacts than the reference fossil fuel system, when the impacts from indirect land use changes are accounted for. In a life-cycle perspective, only highly-efficient co-firing with fossil fuel achieved a (modest) GHG emission reduction.

  3. Global warming and thermohaline circulation stability

    NASA Astrophysics Data System (ADS)

    Wood, Richard A.; Vellinga, Michael; Thorpe, Robert

    2003-09-01

    The Atlantic thermohaline circulation (THC) plays an important role in global climate. Theoretical and palaeoclimatic evidence points to the possibility of rapid changes in the strength of the THC, including a possible quasi-permanent shutdown. The climatic impacts of such a shutdown would be severe, including a cooling throughout the Northern Hemisphere, which in some regions is greater in magnitude than the changes expected from global warming in the next 50 years. Other climatic impacts would likely include a severe alteration of rainfall patterns in the tropics, the Indian subcontinent and Europe. Modelling the future behaviour of the THC focuses on two key questions. (i) Is a gradual weakening of the THC likely in response to global warming, and if so by how much? (ii) Are there thresholds beyond which rapid or irreversible changes in the THC are likely? Most projections of the response of the THC to increasing concentrations of greenhouse gases suggest a gradual weakening over the twenty-first century. However, there is a wide variation between different models over the size of the weakening. Rapid or irreversible THC shutdown is considered a low-probability (but high-impact) outcome; however, some climate models of intermediate complexity do show the possibility of such events. The question of the future of the THC is beset with conceptual, modelling and observational uncertainties, but some current and planned projects show promise to make substantial progress in tackling these uncertainties in future.

  4. Global warming and cyanobacterial harmful algal blooms.

    PubMed

    Paul, Valerie J

    2008-01-01

    The Earth and the oceans have warmed significantly over the past four decades, providing evidence that the Earth is undergoing long-term climate change. Increasing temperatures and changing rainfall patterns have been documented. Cyanobacteria have a long evolutionary history, with their first occurrence dating back at least 2.7 billion years ago. Cyanobacteria often dominated the oceans after past mass extinction events. They evolved under anoxic conditions and are well adapted to environmental stress including exposure to UV, high solar radiation and temperatures, scarce and abundant nutrients. These environmental conditions favor the dominance of cyanobacteria in many aquatic habitats, from freshwater to marine ecosystems. A few studies have examined the ecological consequences of global warming on cyanobacteria and other phytoplankton over the past decades in freshwater, estuarine, and marine environments, with varying results. The responses of cyanobacteria to changing environmental patterns associated with global climate change are important subjects for future research. Results of this research will have ecological and biogeochemical significance as well as management implications.

  5. Identifying the molecular origin of global warming.

    PubMed

    Bera, Partha P; Francisco, Joseph S; Lee, Timothy J

    2009-11-12

    We have investigated the physical characteristics of greenhouse gases (GHGs) to assess which properties are most important in determining the efficiency of a GHG. Chlorofluorocarbons (CFCs), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), nitrogen fluorides, and various other known atmospheric trace molecules have been included in this study. Compounds containing the halogens F or Cl have in common very polar X-F or X-Cl bonds, particularly the X-F bonds. It is shown that as more F atoms bond to the same central atom the bond dipoles become larger as a result of the central atom becoming more positive. This leads to a linear increase in the total or integrated X-F bond dipole derivatives for the molecule, which leads to a nonlinear (quadratic) increase in infrared (IR) intensity. Moreover, virtually all of the X-F bond stretches occur in the atmospheric IR window as opposed to X-H stretches, which do not occur in the atmospheric window. It is concluded that molecules possessing several F atoms will always have a large radiative forcing parameter in the calculation of their global warming potential. Some of the implications for global warming and climate change are discussed.

  6. Photochemical aerosols in warm exoplanetary atmospheres

    NASA Astrophysics Data System (ADS)

    Imanaka, Hiroshi; Smith, Mark A.; McKay, Christopher P.; Cruikshank, Dale P.; Marley, Mark S.

    2016-10-01

    Recent transit observations of exoplanets have demonstrated the possibility of a wide prevalence of haze/cloud layers at high altitudes. Hydrocarbon photochemical haze could be the candidate for such haze particles on warm sub-Neptunes, but the lack of evidence for methane poses a puzzle for such hydrocarbon photochemical haze. The CH4/CO ratios in planetary atmospheres vary substantially from their temperature and dynamics. We have conducted a series of laboratory simulations to investigate how atmospheric compositions, specifically CH4/CO ratios, affect the haze production rates and their optical properties. The mass production rates in the H2-CH4-CO gas mixtures are rather insensitive to the CH4/CO ratios larger than at 0.3. Significant formation of solid material is observed in a H2-CO gas mixture even without CH4. The complex refractive indices of the aerosol analogue from the H2-CO gas mixture show strong absorption at the visible/near-IR wavelengths. These experimental facts imply that substantial carbonaceous aerosols may be generated in warm H2-CO-CH4 exoplanetary atmospheres, and that it might be responsible for the observed dark albedos at the visible wavelengths.

  7. Acupuncture modulates facial warm sensory thresholds.

    PubMed

    Benoliel, Rafael; Zaidan, Shadya; Eliav, Eli

    2011-01-01

    To assess the effects of four- and six-point acupuncture on facial sensory detection thresholds to thermal and electrical stimuli. Ten healthy volunteers underwent four-point acupuncture at ST6 and LI4 bilaterally for 15 minutes. A further 10 subjects underwent six-point acupuncture by adding needling at ST2 bilaterally. Sensory testing to thermal and electrical stimuli applied to mental and infraorbital nerve dermatomes was performed at baseline, 10 minutes, 1 hour, and 1 day after needling. In the mental and infraorbital nerve dermatomes, six-point acupuncture significantly increased warm threshold by a peak mean of 1.1°C to 1.4°C (repeated measures ANOVA P = .001) and this effect was significant at all time points relative to baseline (P < .05). No significant effects were observed by the four-point acupuncture on warm thresholds, and neither four- nor six-point acupuncture significantly altered electrical detection thresholds. A dose effect, related to the number of points employed, may be present when employing acupuncture.

  8. Soft radiative strength in warm nuclei

    SciTech Connect

    Schiller, A; Voinov, A; Agvaanluvsan, U; Algin, E; Becker, J; Belgya, T; Bernstein, L; Chankova, R; Garrett, P E; Guttormsen, M; Mitchell, G E; Nelson, R O; Rekstad, J; Siem, S; Sunde, A C

    2005-09-29

    We present data on the soft (E{sub {gamma}} < 3-4 MeV) radiative strength function (RSF) for electromagnetic transitions between warm states (i.e. states several MeV above the yrast line) from two different types of experiments. The Oslo method provides data on the total level density and the sum (over all multipolarities) of all RSFs by sequential extraction from primary-{gamma} spectra. Measurements of two-step-decay spectra following neutron capture yields two-step-cascade (TSC) intensities which are roughly proportional to the product of two RSFs. Investigations on {sup 172}Yb and {sup 57}Fe have produced unexpected results. In the first case, a strong (B(M1 {up_arrow}) = 6.5 {mu}{sub N}{sup 2}) resonance at E = 3.3 MeV was identified. In the second case, a large (more than a factor of 10) enhancement compared to theoretical estimates of the very soft (E{sub {gamma}} {le} 3 MeV), summed RSF for transitions between warm states was observed. A somewhat weaker (factor {approx} 3) enhancement of the RSF in Mo isotopes observed within the Oslo method still awaits confirmation from TSC experiments.

  9. Cold months in a warming climate

    NASA Astrophysics Data System (ADS)

    Räisänen, Jouni; Ylhäisi, Jussi S.

    2011-11-01

    The frequency of cold months in the 21st century is studied using the CMIP3 ensemble of climate model simulations, using month-, location- and model-specific threshold temperatures derived from the simulated 20th century climate. Unsurprisingly, cold months are projected to become less common, but not non-existent, under continued global warming. As a multi-model mean over the global land area excluding Antarctica and under the SRES A1B scenario, 14% of the months during the years 2011-2050 are simulated to be colder than the 20th century median for the same month, 1.3% colder than the 10th percentile, and 0.1% record cold. The geographic and seasonal variations in the frequency of cold months are strongly modulated by variations in the magnitude of interannual variability. Thus, for example, cold months are most infrequently simulated over the tropical oceans where the variability is smallest, not over the Arctic where the warming is largest.

  10. Does Global Warming Influence Tornado Activity?

    NASA Astrophysics Data System (ADS)

    Diffenbaugh, Noah S.; Trapp, Robert J.; Brooks, Harold

    2008-12-01

    Tornadoes and other severe thunderstorm phenomena frequently cause as much annual property damage in the United States as do hurricanes, and often cause more fatalities (see http://www.nws.noaa.gov/om/hazstats.shtml). In 2008, there were 2176 preliminary tornado reports logged through mid-December, with 1600 ``actual counts'' (duplicate reports removed) through September, the highest total in the past half century (Figure 1). The mass media have covered these events extensively, and experts have been deluged with requests for explanations, including possible links to anthropogenic global warming. Although recent research has yielded insight into the connections between global warming and tornado and severe thunderstorm forcing, these relationships remain mostly unexplored, largely because of the challenges in observing and numerically simulating tornadoes. Indeed, a number of questions that have been answered for other climate-related phenomena remain particularly difficult for climate and severe weather scientists, including whether there are detectable trends in tornado occurrence and if so, what causes them. This article explores the challenges and opportunities in pursuing these areas of research.

  11. Acting green elicits a literal warm glow

    NASA Astrophysics Data System (ADS)

    Taufik, Danny; Bolderdijk, Jan Willem; Steg, Linda

    2015-01-01

    Environmental policies are often based on the assumption that people only act environmentally friendly if some extrinsic reward is implicated, usually money. We argue that people might also be motivated by intrinsic rewards: doing the right thing (such as acting environmentally friendly) elicits psychological rewards in the form of positive feelings, a phenomenon known as warm glow. Given the fact that people's psychological state may affect their thermal state, we expected that this warm glow could express itself quite literally: people who act environmentally friendly may perceive the temperature to be higher. In two studies, we found that people who learned they acted environmentally friendly perceived a higher temperature than people who learned they acted environmentally unfriendly. The underlying psychological mechanism pertains to the self-concept: learning you acted environmentally friendly signals to yourself that you are a good person. Together, our studies show that acting environmentally friendly can be psychologically rewarding, suggesting that appealing to intrinsic rewards can be an alternative way to encourage pro-environmental actions.

  12. Timing the warm absorber in NGC4051

    NASA Astrophysics Data System (ADS)

    Silva, C.; Uttley, P.; Costantini, E.

    2015-07-01

    In this work we have combined spectral and timing analysis in the characterization of highly ionized outflows in Seyfert galaxies, the so-called warm absorbers. Here, we present our results on the extensive ˜600ks of XMM-Newton archival observations of the bright and highly variable Seyfert 1 galaxy NGC4051, whose spectrum has revealed a complex multi-component wind. Working simultaneously with RGS and PN data, we have performed a detailed analysis using a time-dependent photoionization code in combination with spectral and Fourier timing techniques. This method allows us to study in detail the response of the gas due to variations in the ionizing flux of the central source. As a result, we will show the contribution of the recombining gas to the time delays of the most highly absorbed energy bands relative to the continuum (Silva, Uttley & Costantini in prep.), which is also vital information for interpreting the continuum lags associated with propagation and reverberation effects in the inner emitting regions. Furthermore, we will illustrate how this powerful method can be applied to other sources and warm-absorber configurations, allowing for a wide range of studies.

  13. Warming Seas and Melting Ice Sheets

    NASA Image and Video Library

    2017-09-28

    Sea level rise is a natural consequence of the warming of our planet. We know this from basic physics. When water heats up, it expands. So when the ocean warms, sea level rises. When ice is exposed to heat, it melts. And when ice on land melts and water runs into the ocean, sea level rises. For thousands of years, sea level has remained relatively stable and human communities have settled along the planet’s coastlines. But now Earth’s seas are rising. Globally, sea level has risen about eight inches since the beginning of the 20th century and more than two inches in the last 20 years alone. All signs suggest that this rise is accelerating. Read more: go.nasa.gov/1heZn29 Caption: An iceberg floats in Disko Bay, near Ilulissat, Greenland, on July 24, 2015. The massive Greenland ice sheet is shedding about 300 gigatons of ice a year into the ocean, making it the single largest source of sea level rise from melting ice. Credits: NASA/Saskia Madlener NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  14. 21-SPONGE Detects Unexpectedly "Warm" Neutral Medium

    NASA Astrophysics Data System (ADS)

    Murray, Claire; Lindner, Robert; Stanimirovic, Snezana; Babler, Brian L.; 21-Sponge Team

    2015-01-01

    We present results from "21 cm Spectral Line Observations of Neutral Gas with the (E)VLA" (21-SPONGE), a large survey for Galactic HI absorption with the Karl G. Jansky Very Large Array (VLA). With RMS noise in optical depth of <10-3 per 0.42 km/s channel over 58 lines of sight (40 fully analyzed), 21-SPONGE is the largest HI absorption survey with such high sensitivity ever undertaken. This sensitivity allows us to detect weak absorption by diffuse, warm HI (``warm neutral medium", WNM) directly, and to measure its previously-unconstrained physical properties. We obtain corresponding HI emission spectra from the Arecibo Observatory and calculate column densities and spin temperatures of Gaussian-fitted clouds along each line of sight. To maximize our sensitivity, we stacked the spectral residuals from the first 19 sources, and detected a statistical WNM absorption signature with Ts= 7200(+1800,-1200) K (68% confidence). This high temperature requires a significantly larger density of Lya photons in the ISM than is predicted by recent theoretical and numerical studies. We extend this analysis to measure the effect of Galactic environment on statistical WNM properties.

  15. Multi-species collapses at the warm edge of a warming sea

    PubMed Central

    Rilov, Gil

    2016-01-01

    Even during the current biodiversity crisis, reports on population collapses of highly abundant, non-harvested marine species were rare until very recently. This is starting to change, especially at the warm edge of species’ distributions where populations are more vulnerable to stress. The Levant basin is the southeastern edge of distribution of most Mediterranean species. Coastal water conditions are naturally extreme, and are fast warming, making it a potential hotspot for species collapses. Using multiple data sources, I found strong evidence for major, sustained, population collapses of two urchins, one large predatory gastropod and a reef-building gastropod. Furthermore, of 59 molluscan species once-described in the taxonomic literature as common on Levant reefs, 38 were not found in the present-day surveys, and there was a total domination of non-indigenous species in molluscan assemblages. Temperature trends indicate an exceptional warming of the coastal waters in the past three decades. Though speculative at this stage, the fast rise in SST may have helped pushing these invertebrates beyond their physiological tolerance limits leading to population collapses and possible extirpations. If so, these collapses may indicate the initiation of a multi-species range contraction at the Mediterranean southeastern edge that may spread westward with additional warming. PMID:27853237

  16. Microbial communities respond to experimental warming, but site matters.

    PubMed

    Cregger, Melissa A; Sanders, Nathan J; Dunn, Robert R; Classen, Aimée T

    2014-01-01

    Because microorganisms are sensitive to temperature, ongoing global warming is predicted to influence microbial community structure and function. We used large-scale warming experiments established at two sites near the northern and southern boundaries of US eastern deciduous forests to explore how microbial communities and their function respond to warming at sites with differing climatic regimes. Soil microbial community structure and function responded to warming at the southern but not the northern site. However, changes in microbial community structure and function at the southern site did not result in changes in cellulose decomposition rates. While most global change models rest on the assumption that taxa will respond similarly to warming across sites and their ranges, these results suggest that the responses of microorganisms to warming may be mediated by differences across the geographic boundaries of ecosystems.

  17. Microbial communities respond to experimental warming, but site matters

    PubMed Central

    Sanders, Nathan J.; Dunn, Robert R.; Classen, Aimée T.

    2014-01-01

    Because microorganisms are sensitive to temperature, ongoing global warming is predicted to influence microbial community structure and function. We used large-scale warming experiments established at two sites near the northern and southern boundaries of US eastern deciduous forests to explore how microbial communities and their function respond to warming at sites with differing climatic regimes. Soil microbial community structure and function responded to warming at the southern but not the northern site. However, changes in microbial community structure and function at the southern site did not result in changes in cellulose decomposition rates. While most global change models rest on the assumption that taxa will respond similarly to warming across sites and their ranges, these results suggest that the responses of microorganisms to warming may be mediated by differences across the geographic boundaries of ecosystems. PMID:24795850

  18. Regional warming of hot extremes accelerated by surface energy fluxes

    NASA Astrophysics Data System (ADS)

    Donat, M. G.; Pitman, A. J.; Seneviratne, S. I.

    2017-07-01

    Strong regional differences exist in how hot temperature extremes increase under global warming. Using an ensemble of coupled climate models, we examine the regional warming rates of hot extremes relative to annual average warming rates in the same regions. We identify hot spots of accelerated warming of model-simulated hot extremes in Europe, North America, South America, and Southeast China. These hot spots indicate where the warm tail of a distribution of temperatures increases faster than the average and are robust across most Coupled Model Intercomparison Project Phase 5 models. Exploring the conditions on the specific day when the hot extreme occurs demonstrates that the hot spots are explained by changes in the surface energy fluxes consistent with drying soils. However, the model-simulated accelerated warming of hot extremes appears inconsistent with observations, except over Europe. The simulated acceleration of hot extremes may therefore be unreliable, a result that necessitates a reevaluation of how climate models resolve the relevant terrestrial processes.

  19. Temperature and size variabilities of the Western Pacific Warm Pool

    NASA Technical Reports Server (NTRS)

    Yan, Xiao-Hai; Ho, Chung-Ru; Zheng, Quanan; Klemas, Vic

    1992-01-01

    Variabilities in sea-surface temperature and size of the Western Pacific Warm Pool were tracked with 10 years of satellite multichannel sea-surface temperature observations from 1982 to 1991. The results show that both annual mean sea-surface temperature and the size of the warm pool increased from 1983 to 1987 and fluctuated after 1987. Possible causes of these variations include solar irradiance variabilities, El Nino-Southern Oscillaton events, volcanic activities, and global warming.

  20. The impact of global warming on Mount Everest.

    PubMed

    Moore, G W K; Semple, John L

    2009-01-01

    Global warming impacts a wide range of human activities and ecosystems. One unanticipated consequence of the warming is an increase in barometric pressure throughout the troposphere. Mount Everest's extreme height and resulting low barometric pressure places humans near its summit in an extreme state of hypoxia. Here we quantify the degree with which this warming is increasing the barometric pressure near Everest's summit and argue that it is of such a magnitude as to make the mountain, over time, easier to climb.

  1. 100 LPW 800 Lm Warm White LED

    SciTech Connect

    Sun, Decai

    2010-10-31

    An illumination grade warm white (WW) LED, having correlated color temperature (CCT) between 2800 K and 3500K and capable of producing 800 lm output at 100 lm/W, has been developed in this program. The high power WW LED is an ideal source for use as replacement for incandescent, and Halogen reflector and general purpose lamps of similar lumen value. Over the two year period, we have made following accomplishments: developed a high power warm white LED product and made over 50% improvements in light output and efficacy. The new high power WW LED product is a die on ceramic surface mountable LED package. It has four 1x1 mm{sup 2} InGaN pump dice flip chip attached to a ceramic submount in 2x2 array, covered by warm white phosphor ceramic platelets called Lumiramica and an overmolded silicone lens encapsulating the LED array. The performance goal was achieved through breakthroughs in following key areas: (1) High efficiency pump LED development through pump LED active region design and epi growth quality improvement (funded by internal programs). (2) Increase in injection efficiency (IE) represented by reduction in forward voltage (V{sub f}) through the improvement of the silver-based p-contact and a reduction in spreading resistance. The injection efficiency was increased from 80% at the start of the program to 96% at the end of the program at 700 mA/mm{sup 2}. (3) Improvement in thermal design as represented by reduction in thermal resistance from junction to case, through improvement of the die to submount connection in the thin film flip chip (TFFC) LED and choosing the submount material of high thermal conductivity. A thermal resistance of 1.72 K/W was demonstrated for the high power LED package. (4) Improvement in extraction efficiency from the LED package through improvement of InGaN die level and package level optical extraction efficiency improvement. (5) Improvement in phosphor system efficiency by improving the lumen equivalent (LE) and phosphor package

  2. Deglacial Warming and Wetting of Northern Alaska

    NASA Astrophysics Data System (ADS)

    Daniels, W.; Russell, J. M.; Longo, W. M.; Giblin, A. E.; Holland-Stergar, P.; Morrill, C.; Huang, Y.

    2015-12-01

    Aeolian sand dunes swept across northern Alaska during the last glacial maximum. Today, summer temperatures are moderate and soils can remain waterlogged all summer long. How did the transition from a cold and dry glacial to a warm and wet interglacial take place? To answer this question we reconstructed temperature and precipitation changes during the last deglaciation using biomarker hydrogen isotopes from a new 28,000 year-long sediment core from Lake E5, located in the central Brooks Range of Alaska. We use terrestrial leaf waxes (dDterr, C28-acid), informed by dD measurements of modern vegetation, to infer dD of precipitation, an indicator of relative temperature change. Biomarkers from aquatic organisms (dDaq, C18-acid) are used as a proxy for lake water isotopes. The offset between the two (eterr-aq) is used to infer relative changes in evaporative enrichment of lake water, and by extension, moisture balance. dDterr during the last glacial period was -282‰ compared to -258‰ during the Holocene, suggesting a 5.6 ± 2.7 °C increase in summer temperature using the modern local temperature-dD relationship. Gradual warming began at ~18.5 ka, and temperature increased abruptly at 11.5 ka, at the end of the Younger Dryas. Warming peaked in the early Holocene from 11.5 to 9.1 ka, indicating a Holocene thermal maximum associated with peak summer insolation. The eterr-aq supports a dry LGM and moist Holocene. Other sediment proxies (TIC, TOC, redox-sensitive elements) support the eterr-aq, and reveal a shift to more positive P-E beginning around 17 ka, suggesting rising temperature led increases in precipitation during the last deglaciation. Moreover, differing patterns of dDterr and eterr-aq during the deglaciation suggest that the relationship between temperature and precipitation changed through time. Such decoupling, likely due to regional atmospheric reorganization as the Laurentide ice sheet waned, illustrates the importance of atmospheric dynamics in

  3. Drought under Global Warming: A Review

    NASA Astrophysics Data System (ADS)

    Dai, A.

    2011-12-01

    One of the big concerns associated with global warming is the potential change to land surface moisture conditions that could have a huge impact on agriculture, freshwater resources, and many other aspects of our society and the environment. How drought has changed during recent past and how it might change in the coming decades is increasingly becoming a great concern as global warming continues and more severe droughts are reported in the media. In this presentation, I will provide an overview, based on my own and others' work, of how drought has changed in the last several centuries and during recent decades over many regions around the world based on historical records, and how it might change in the coming decades based on IPCC AR4 model-predicted climate changes. I will present results from analyses of changes in precipitation, streamflow, soil moisture, and (improved) Palmer Drought Severity Index (PDSI) to show that aridity has increased during the last 50-60 years over many land areas, and rapid warming since the 1980s has contributed significantly to this drying. The PDSI (with improved evapotranspiration estimates) calculated from the AR4 multi-model predicted future climate suggests severe drying in the next 20-50 years over most land areas except the northern high-latitudes and parts of Asia. This drying pattern is consistent with other analyses of model-predicted soil moisture and precipitation changes. Although the quantitative interpretation of the future PDSI values may need to be cautious, combined with the other analyses, the PDSI result points to a dire situation with more severe to extreme droughts in the coming decades over the continental U.S., most of Africa and South America, Australia, southern Europe, and western and southeastern Asia. Changes in precipitation play an important role over many land areas, but enhanced evaporation due to increased radiative heating is also a major factor for the model-predicted drying. For more details, see

  4. Anesthesia and global warming: the real hazards of theoretic science

    PubMed Central

    2012-01-01

    Recent speculative articles in the medical literature have indicted certain inhalational anesthetics as contributing to global warming. This unfounded speculation may have deleterious patient impact PMID:22444758

  5. Mechanisms for stronger warming over drier ecoregions observed since 1979

    NASA Astrophysics Data System (ADS)

    Zhou, Liming; Chen, Haishan; Hua, Wenjian; Dai, Yongjiu; Wei, Nan

    2016-11-01

    Previous research found that the warming rate observed for the period 1979-2012 increases dramatically with decreasing vegetation greenness over land between 50°S and 50°N, with the strongest warming rate seen over the driest regions such as the Sahara desert and the Arabian Peninsula, suggesting warming amplification over deserts. To further this finding, this paper explores possible mechanisms for this amplification by analyzing observations, reanalysis data and historical simulations of global coupled atmosphere-ocean general circulation models. We examine various variables, related to surface radiative forcing, land surface properties, and surface energy and radiation budget, that control the warming patterns in terms of large-scale ecoregions. Our results indicate that desert amplification is likely attributable primarily to enhanced longwave radiative forcing associated with a stronger water vapor feedback over drier ecoregions in response to the positive global-scale greenhouse gas forcing. This warming amplification and associated downward longwave radiation at the surface are reproduced by historical simulations with anthropogenic and natural forcings, but are absent if only natural forcings are considered, pointing to new potential fingerprints of anthropogenic warming. These results suggest a fundamental pattern of global warming over land that depend on the dryness of ecosystems in mid- and low- latitudes, likely reflecting primarily the first order large-scale thermodynamic component of global warming linked to changes in the water and energy cycles over different ecosystems. This finding may have important implications in interpreting global warming patterns and assessing climate change impacts.

  6. Global warming and neurodegenerative disorders: speculations on their linkage.

    PubMed

    Habibi, Laleh; Perry, George; Mahmoudi, Morteza

    2014-01-01

    Climate change is having considerable impact on biological systems. Eras of ice ages and warming shaped the contemporary earth and origin of creatures including humans. Warming forces stress conditions on cells. Therefore, cells evolved elaborate defense mechanisms, such as creation of heat shock proteins, to combat heat stress. Global warming is becoming a crisis and this process would yield an undefined increasing rate of neurodegenerative disorders in future decades. Since heat stress is known to have a degenerative effects on neurons and, conversely, cold conditions have protective effect on these cells, we hypothesize that persistent heat stress forced by global warming might play a crucial role in increasing neurodegenerative disorders.

  7. Precompetition warm-up in elite and subelite rhythmic gymnastics.

    PubMed

    Guidetti, Laura; Di Cagno, Alessandra; Gallotta, Maria Chiara; Battaglia, Claudia; Piazza, Marina; Baldari, Carlo

    2009-09-01

    The aim of this study was to investigate which precompetition warm-up methodologies resulted in the best overall performance in rhythmic gymnastics. The coaches of national and international clubs (60 elite and 90 subelite) were interviewed. The relationship between sport performance and precompetition warm-up routines was examined. A total of 49% of the coaches interviewed spent more than 1 hour to prepare their athletes for the competition, including 45 minutes dedicated to warm-up exercises. In spite of previous studies' suggestions, the time between the end of warm-up and the beginning of competition was more than 5 minutes for 68% of those interviewed. A slow run was the activity of choice used to begin the warm-up (96%). Significant differences between elite and subelite gymnasts were found concerning the total duration of warm-up, duration of slow running, utilization of rhythmic steps and leaps during the warm-up, the use of dynamic flexibility exercises, competition performances repetition (p < 0.01), and utilization of imagery (p < 0.05). A precompetition warm-up in rhythmic gymnastics would include static stretching exercises at least 60 minutes prior to the competition starting time and the active stretching exercises alternated with analytic muscle strengthening aimed at increasing muscle temperature. Rhythmic gymnastics coaches at all levels can use this data as a review of precompetition warm-up practices and a possible source of new ideas.

  8. Sustaining effect of soil warming on organic matter decomposition

    NASA Astrophysics Data System (ADS)

    Hou, Ruixing; Ouyang, Zhu; Dorodnikov, Maxim; Wilson, Glenn; Kuzyakov, Yakov

    2015-04-01

    Global warming affects various parts of carbon (C) cycle including acceleration of soil organic matter (SOM) decomposition with strong feedback to atmospheric CO2 concentration. Despite many soil warming studies showed changes of microbial community structure, only very few were focused on sustainability of soil warming on microbial activity associated with SOM decomposition. Two alternative hypotheses: 1) acclimation because of substrate exhaustion and 2) sustaining increase of microbial activity with accelerated decomposition of recalcitrant SOM pools were never proven under long term field conditions. This is especially important in the nowadays introduced no-till crop systems leading to redistribution of organic C at the soil surface, which is much susceptible to warming effects than the rest of the profile. We incubated soil samples from a four-year warming experiment with tillage (T) and no-tillage (NT) practices under three temperatures: 15, 21, and 27 °C, and related the evolved total CO2 efflux to changes of organic C pools. Warmed soils released significantly more CO2 than the control treatment (no warming) at each incubation temperature, and the largest differences were observed under 15 °C (26% increase). The difference in CO2 efflux from NT to T increase with temperature showing high vulnerability of C stored in NT to soil warming. The Q10 value reflecting the sensitivity of SOM decomposition to warming was lower for warmed than non-warmed soil indicating better acclimation of microbes or lower C availability during long term warming. The activity of three extracellular enzymes: β-glucosidase, chitinase, sulphatase, reflecting the response of C, N and S cycles to warming, were significantly higher under warming and especially under NT compared to two other respective treatments. The CO2 released during 2 months of incubation consisted of 85% from recalcitrant SOM and the remaining 15% from microbial biomass and extractable organic C based on the

  9. Southern Ocean warming delayed by circumpolar upwelling and equatorward transport

    NASA Astrophysics Data System (ADS)

    Armour, Kyle C.; Marshall, John; Scott, Jeffery R.; Donohoe, Aaron; Newsom, Emily R.

    2016-07-01

    The Southern Ocean has shown little warming over recent decades, in stark contrast to the rapid warming observed in the Arctic. Along the northern flank of the Antarctic Circumpolar Current, however, the upper ocean has warmed substantially. Here we present analyses of oceanographic observations and general circulation model simulations showing that these patterns--of delayed warming south of the Antarctic Circumpolar Current and enhanced warming to the north--are fundamentally shaped by the Southern Ocean's meridional overturning circulation: wind-driven upwelling of unmodified water from depth damps warming around Antarctica; greenhouse gas-induced surface heat uptake is largely balanced by anomalous northward heat transport associated with the equatorward flow of surface waters; and heat is preferentially stored where surface waters are subducted to the north. Further, these processes are primarily due to passive advection of the anomalous warming signal by climatological ocean currents; changes in ocean circulation are secondary. These findings suggest the Southern Ocean responds to greenhouse gas forcing on the centennial, or longer, timescale over which the deep ocean waters that are upwelled to the surface are warmed themselves. It is against this background of gradual warming that multidecadal Southern Ocean temperature trends must be understood.

  10. Plant community responses to experimental warming across the tundra biome

    PubMed Central

    Walker, Marilyn D.; Wahren, C. Henrik; Hollister, Robert D.; Henry, Greg H. R.; Ahlquist, Lorraine E.; Alatalo, Juha M.; Bret-Harte, M. Syndonia; Calef, Monika P.; Callaghan, Terry V.; Carroll, Amy B.; Epstein, Howard E.; Jónsdóttir, Ingibjörg S.; Klein, Julia A.; Magnússon, Borgþór; Molau, Ulf; Oberbauer, Steven F.; Rewa, Steven P.; Robinson, Clare H.; Shaver, Gaius R.; Suding, Katharine N.; Thompson, Catharine C.; Tolvanen, Anne; Totland, Ørjan; Turner, P. Lee; Tweedie, Craig E.; Webber, Patrick J.; Wookey, Philip A.

    2006-01-01

    Recent observations of changes in some tundra ecosystems appear to be responses to a warming climate. Several experimental studies have shown that tundra plants and ecosystems can respond strongly to environmental change, including warming; however, most studies were limited to a single location and were of short duration and based on a variety of experimental designs. In addition, comparisons among studies are difficult because a variety of techniques have been used to achieve experimental warming and different measurements have been used to assess responses. We used metaanalysis on plant community measurements from standardized warming experiments at 11 locations across the tundra biome involved in the International Tundra Experiment. The passive warming treatment increased plant-level air temperature by 1-3°C, which is in the range of predicted and observed warming for tundra regions. Responses were rapid and detected in whole plant communities after only two growing seasons. Overall, warming increased height and cover of deciduous shrubs and graminoids, decreased cover of mosses and lichens, and decreased species diversity and evenness. These results predict that warming will cause a decline in biodiversity across a wide variety of tundra, at least in the short term. They also provide rigorous experimental evidence that recently observed increases in shrub cover in many tundra regions are in response to climate warming. These changes have important implications for processes and interactions within tundra ecosystems and between tundra and the atmosphere. PMID:16428292

  11. Plant community responses to experimental warming across the tundra biome.

    PubMed

    Walker, Marilyn D; Wahren, C Henrik; Hollister, Robert D; Henry, Greg H R; Ahlquist, Lorraine E; Alatalo, Juha M; Bret-Harte, M Syndonia; Calef, Monika P; Callaghan, Terry V; Carroll, Amy B; Epstein, Howard E; Jónsdóttir, Ingibjörg S; Klein, Julia A; Magnússon, Borgthór; Molau, Ulf; Oberbauer, Steven F; Rewa, Steven P; Robinson, Clare H; Shaver, Gaius R; Suding, Katharine N; Thompson, Catharine C; Tolvanen, Anne; Totland, Ørjan; Turner, P Lee; Tweedie, Craig E; Webber, Patrick J; Wookey, Philip A

    2006-01-31

    Recent observations of changes in some tundra ecosystems appear to be responses to a warming climate. Several experimental studies have shown that tundra plants and ecosystems can respond strongly to environmental change, including warming; however, most studies were limited to a single location and were of short duration and based on a variety of experimental designs. In addition, comparisons among studies are difficult because a variety of techniques have been used to achieve experimental warming and different measurements have been used to assess responses. We used metaanalysis on plant community measurements from standardized warming experiments at 11 locations across the tundra biome involved in the International Tundra Experiment. The passive warming treatment increased plant-level air temperature by 1-3 degrees C, which is in the range of predicted and observed warming for tundra regions. Responses were rapid and detected in whole plant communities after only two growing seasons. Overall, warming increased height and cover of deciduous shrubs and graminoids, decreased cover of mosses and lichens, and decreased species diversity and evenness. These results predict that warming will cause a decline in biodiversity across a wide variety of tundra, at least in the short term. They also provide rigorous experimental evidence that recently observed increases in shrub cover in many tundra regions are in response to climate warming. These changes have important implications for processes and interactions within tundra ecosystems and between tundra and the atmosphere.

  12. Global warming and neurodegenerative disorders: speculations on their linkage

    PubMed Central

    Habibi, Laleh; Perry, George; Mahmoudi, Morteza

    2014-01-01

    Climate change is having considerable impact on biological systems. Eras of ice ages and warming shaped the contemporary earth and origin of creatures including humans. Warming forces stress conditions on cells. Therefore, cells evolved elaborate defense mechanisms, such as creation of heat shock proteins, to combat heat stress. Global warming is becoming a crisis and this process would yield an undefined increasing rate of neurodegenerative disorders in future decades. Since heat stress is known to have a degenerative effects on neurons and, conversely, cold conditions have protective effect on these cells, we hypothesize that persistent heat stress forced by global warming might play a crucial role in increasing neurodegenerative disorders. PMID:25671171

  13. Microwave sounding units and global warming

    NASA Technical Reports Server (NTRS)

    Gary, Bruce L.; Keihm, Stephen J.

    1991-01-01

    A recent work of Spencer and Christy (1990) on precise monitoring of global temperature trends from satellites is critically examined. It is tentatively concluded in the present comment that remote sensing using satellite microwave radiometers can in fact provide a means for the monitoring of troposphere-averaged air temperature. However, for this to be successful more than one decade of data will be required to overcome the apparent inherent variability of global average air temperature. It is argued that the data set reported by Spencer and Christy should be subjected to careful review before it is interpreted as evidence of the presence or absence of global warming. In a reply, Christy provides specific responses to the commenters' objections.

  14. Microwave sounding units and global warming

    NASA Technical Reports Server (NTRS)

    Gary, Bruce L.; Keihm, Stephen J.

    1991-01-01

    A recent work of Spencer and Christy (1990) on precise monitoring of global temperature trends from satellites is critically examined. It is tentatively concluded in the present comment that remote sensing using satellite microwave radiometers can in fact provide a means for the monitoring of troposphere-averaged air temperature. However, for this to be successful more than one decade of data will be required to overcome the apparent inherent variability of global average air temperature. It is argued that the data set reported by Spencer and Christy should be subjected to careful review before it is interpreted as evidence of the presence or absence of global warming. In a reply, Christy provides specific responses to the commenters' objections.

  15. Ecologic simulation of warm water aquaculture ponds

    SciTech Connect

    Piedrahitu, R.H.; Brune, D.E.; Orlob, G.T.; Tchobanoglous, G.

    1983-06-01

    A generalized ecologic model of a fertilized warm-water aquaculture pond is under development. The model is intended to represent the pond ecosystem and its response to external stimuli. The major physical, chemical and biological processes and parameters are included in the model. A total of 19 state variables are included in the model (dissolved oxygen, alkalinity, pH, ammonia, phytoplankton, etc.). The model is formulated as a system of mass balance equations. The equations include stimulatory and inhibitory effects of environmental parameters on processes taking place in the pond. The equations may be solved for the entire growth period and diurnal as well as seasonal fluctuations may be identified. The ultimate objective of the model is to predict the fish biomass that can be produced in a pond under a given set of environmental conditions.

  16. Mass loss from warm giants: Magnetic effects

    NASA Technical Reports Server (NTRS)

    Mullan, D. J.

    1980-01-01

    Among warm giant stars, rapid mass loss sets in along a well defined velocity dividing line (VDL). Hot corona also disappear close to the VDL and thermal pressure cannot drive the observed rapid mass loss in these stars. The VDL may be associated with magnetic fields changing from closed to open. Such a change is consistent with the lack of X-rays from late-type giants. A magnetic transition locus based on Pneuman's work on helmet streamer stability agrees well with the empirical VDL. The change from closed to open fields not only makes rapid mass loss possible, but also contributes to energizing the mass loss in the form of discrete bubbles.

  17. The Warm-Hot Intergalactic Medium

    NASA Technical Reports Server (NTRS)

    Hayes, Jeffrey (Technical Monitor)

    2005-01-01

    This grant is associated to a 5-year LTSA grant, on "Studying the Largest Reservoir of Baryons in the Universe: The Warm-Hot Intergalactic Medium". The first year of work within this program has been very rich, and has already produced several important results, as detailed in this paper. Table 2 of our original proposal justification, listed the planned year-by-year program, divided into two sub-fields: (A) the study of the z=0 (or Local Group WHIM) system, and (B) the study of the z greater than 0 (i.e- intervening WHIM) systems. For each of the two sub-fields we had planned to analyze, in the first year, a number of archival (Chandra, XMM and FUSE) and new (if observed) sightlines. Moreover, the plan for the z=0 system included the search for new interesting sightlines. We have accomplished all these tasks.

  18. Does global warming make Triton blush?

    NASA Astrophysics Data System (ADS)

    Buratti, Bonnie J.; Hicks, Michael D.; Newburn, Ray L., Jr.

    1999-01-01

    Neptune's largest moon, Triton, is one of two satellites in the Solar System that are currently geologically active. At least two geyser-like plumes were observed by the Voyager 2 spacecraft in 1989, and dozens of streaky deposits hint at the existence of many more. Triton also exhibits complex seasonal changes in its 165-year journey about the Sun. Because Triton's atmosphere transports volatiles (primarily nitrogen and methane) during this seasonal cycle, its atmospheric pressure may fluctuate by up to an order of magnitude over decades. Photometric measurements of its albedo and colour over half a century show that seasonal volatile transport has occurred. There have also been indications that more extreme, short-lived changes, perhaps due to geological events, have occurred on Triton. An anomalously red spectrum was reported for Triton in 1977 (refs 5, 6), and global warming has now been observed.

  19. Seasonal flows on warm Martian slopes

    USGS Publications Warehouse

    McEwen, A.S.; Ojha, L.; Dundas, C.M.; Mattson, S.S.; Byrne, S.; Wray, J.J.; Cull, S.C.; Murchie, S.L.; Thomas, N.; Gulick, V.C.

    2011-01-01

    Water probably flowed across ancient Mars, but whether it ever exists as a liquid on the surface today remains debatable. Recurring slope lineae (RSL) are narrow (0.5 to 5 meters), relatively dark markings on steep (25?? to 40??) slopes; repeat images from the Mars Reconnaissance Orbiter High Resolution Imaging Science Experiment show them to appear and incrementally grow during warm seasons and fade in cold seasons. They extend downslope from bedrock outcrops, often associated with small channels, and hundreds of them form in some rare locations. RSL appear and lengthen in the late southern spring and summer from 48??S to 32??S latitudes favoring equator-facing slopes, which are times and places with peak surface temperatures from ???250 to 300 kelvin. Liquid brines near the surface might explain this activity, but the exact mechanism and source of water are not understood.

  20. Seasonal flows on warm Martian slopes

    USGS Publications Warehouse

    McEwen, Alfred S.; Ojha, Lujendra; Dundas, Colin M.; Mattson, Sarah S.; Byrne, Shane; Wray, James J.; Cull, Selby C.; Murchie, Scott L.; Thomas, Nicolas; Gulick, Virginia C.

    2011-01-01

    Water probably flowed across ancient Mars, but whether it ever exists as a liquid on the surface today remains debatable. Recurring slope lineae (RSL) are narrow (0.5 to 5 meters), relatively dark markings on steep (25° to 40°) slopes; repeat images from the Mars Reconnaissance Orbiter High Resolution Imaging Science Experiment show them to appear and incrementally grow during warm seasons and fade in cold seasons. They extend downslope from bedrock outcrops, often associated with small channels, and hundreds of them form in some rare locations. RSL appear and lengthen in the late southern spring and summer from 48°S to 32°S latitudes favoring equator-facing slopes, which are times and places with peak surface temperatures from ~250 to 300 kelvin. Liquid brines near the surface might explain this activity, but the exact mechanism and source of water are not understood.

  1. Status of warm fog dispersal research

    NASA Technical Reports Server (NTRS)

    Keller, V. W.

    1985-01-01

    A new concept for dispersing warm fog is presented. This brute force technique uses large volume recycled water sprays. Energy requirements for this technique are an order of magnitude less than those to operate a thermo-kinetic system. An important side benefit is the considerable emergency fire extinguishing capability it provides along the runway. Tests conducted to provide drop spectra measurements and temperature response measurements of suitable water sprays are described. Three mobile firefighting modules capable of spraying up to 630 l/s (10,000 gpm) to a height in excess of 50 m were utilized. Periodic operation of two parallel rows of nozzles in a heavy fog resulted in downwind-correlated increases in the visual range measured with a forward scatter visibility meter.

  2. Ocean deoxygenation in a warming world.

    PubMed

    Keeling, Ralph E; Körtzinger, Arne; Gruber, Nicolas

    2010-01-01

    Ocean warming and increased stratification of the upper ocean caused by global climate change will likely lead to declines in dissolved O2 in the ocean interior (ocean deoxygenation) with implications for ocean productivity, nutrient cycling, carbon cycling, and marine habitat. Ocean models predict declines of 1 to 7% in the global ocean O2 inventory over the next century, with declines continuing for a thousand years or more into the future. An important consequence may be an expansion in the area and volume of so-called oxygen minimum zones, where O2 levels are too low to support many macrofauna and profound changes in biogeochemical cycling occur. Significant deoxygenation has occurred over the past 50 years in the North Pacific and tropical oceans, suggesting larger changes are looming. The potential for larger O2 declines in the future suggests the need for an improved observing system for tracking ocean 02 changes.

  3. Global warming tugs at trophic interactions.

    PubMed

    Brook, Barry W

    2009-01-01

    Climate change impacts are becoming increasingly evident as 1 degree C warming above pre-industrial temperatures is approached. One of the signature biological effects is a shift towards earlier-timed reproduction. If individual species lack sufficient adaptive plasticity to alter phenology, they will have reduced fitness in a hotter world. Yet, a long-term study of an oak-caterpillar-songbird-sparrowhawk food web reveals that what could matter as much is if trophic interactions are disrupted. Multiple selective pressures may be triggered by climate change, leading to a tug-of-war between the need to stay in synchrony with the timing of maximum food, and the benefits of minimizing predation.

  4. Global warming and changes in ocean circulation

    SciTech Connect

    Duffy, P.B.; Caldeira, K.C.

    1998-02-01

    This final report provides an overview of the goals and accomplishments of this project. Modeling and observational work has raised the possibility that global warming may cause changes in the circulation of the ocean. If such changes would occur they could have important climatic consequences. The first technical goal of this project was to investigate some of these possible changes in ocean circulation in a quantitative way, using a state-of -the-art numerical model of the ocean. Another goal was to develop our ocean model, a detailed three-dimensional numerical model of the ocean circulation and ocean carbon cycles. A major non-technical goal was to establish LLNL as a center of excellence in modelling the ocean circulation and carbon cycle.

  5. Gravitino Warm Dark Matter with Entropy Production

    SciTech Connect

    Baltz, Edward A.; Murayama, Hitoshi

    2001-08-09

    Gravitinos with a mass in the keV range are an interesting candidate for warm dark matter. Recent measurements of the matter density of the universe and of cosmic structures at the dwarf galaxy scale rule out the simplest gravitino models with thermal freeze-out. We construct a model where the decay of the messenger particles that transmit the supersymmetry breaking to the observable sector generates the required entropy to dilute the gravitino relic density by the required factor of a few to come in line with observations. The model is natural, and requires only that the coupling of the messenger sector to the standard model be set so that the decay happens at the appropriate time.

  6. Sea ice thickness and recent Arctic warming

    NASA Astrophysics Data System (ADS)

    Lang, Andreas; Yang, Shuting; Kaas, Eigil

    2017-01-01

    The climatic impact of increased Arctic sea ice loss has received growing attention in the last years. However, little focus has been set on the role of sea ice thickness, although it strongly determines surface heat fluxes. Here ensembles of simulations using the EC-Earth atmospheric model (Integrated Forecast System) are performed and analyzed to quantify the atmospheric impacts of Arctic sea ice thickness change since 1982 as revealed by the sea ice model assimilation Global Ice-Ocean Modeling and Assimilation System. Results show that the recent sea ice thinning has significantly affected the Arctic climate, while remote atmospheric responses are less pronounced owing to a high internal atmospheric variability. Locally, the sea ice thinning results in enhancement of near-surface warming of about 1°C per decade in winter, which is most pronounced over marginal sea ice areas with thin ice. This leads to an increase of the Arctic amplification factor by 37%.

  7. Revaluating ocean warming impacts on global phytoplankton

    NASA Astrophysics Data System (ADS)

    Behrenfeld, Michael J.; O'Malley, Robert T.; Boss, Emmanuel S.; Westberry, Toby K.; Graff, Jason R.; Halsey, Kimberly H.; Milligan, Allen J.; Siegel, David A.; Brown, Matthew B.

    2016-03-01

    Global satellite observations document expansions of the low-chlorophyll central ocean gyres and an overall inverse relationship between anomalies in sea surface temperature and phytoplankton chlorophyll concentrations. These findings can provide an invaluable glimpse into potential future ocean changes, but only if the story they tell is accurately interpreted. Chlorophyll is not simply a measure of phytoplankton biomass, but also registers changes in intracellular pigmentation arising from light-driven (photoacclimation) and nutrient-driven physiological responses. Here, we show that the photoacclimation response is an important component of temporal chlorophyll variability across the global ocean. This attribution implies that contemporary relationships between chlorophyll changes and ocean warming are not indicative of proportional changes in productivity, as light-driven decreases in chlorophyll can be associated with constant or even increased photosynthesis. Extension of these results to future change, however, requires further evaluation of how the multifaceted stressors of a warmer, higher-CO2 world will impact plankton communities.

  8. Ion beam driven warm dense matter experiments

    NASA Astrophysics Data System (ADS)

    Bieniosek, F. M.; Ni, P. A.; Leitner, M.; Roy, P. K.; More, R.; Barnard, J. J.; Kireeff Covo, M.; Molvik, A. W.; Yoneda, H.

    2007-11-01

    We report plans and experimental results in ion beam-driven warm dense matter (WDM) experiments. Initial experiments at LBNL are at 0.3-1 MeV K+ beam (below the Bragg peak), increasing toward the Bragg peak in future versions of the accelerator. The WDM conditions are envisioned to be achieved by combined longitudinal and transverse neutralized drift compression to provide a hot spot on the target with a beam spot size of about 1 mm, and pulse length about 1-2 ns. The range of the beams in solid matter targets is about 1 micron, which can be lengthened by using porous targets at reduced density. Initial experiments include an experiment to study transient darkening at LBNL; and a porous target experiment at GSI heated by intense heavy-ion beams from the SIS 18 storage ring. Further experiments will explore target temperature and other properties such as electrical conductivity to investigate phase transitions and the critical point.

  9. Responses of terrestrial aridity to global warming

    NASA Astrophysics Data System (ADS)

    Fu, Qiang; Feng, Song

    2014-07-01

    The dryness of terrestrial climate can be measured by the ratio of annual precipitation (P) to potential evapotranspiration (PET), where the latter represents the evaporative demand of the atmosphere, which depends on the surface air temperature, relative humidity, wind speed, and available energy. This study examines how the terrestrial mean aridity responds to global warming in terms of P/PET using the Coupled Model Intercomparison Project phase 5 transient CO2 increase to 2 × CO2 simulations. We show that the (percentage) increase (rate) in P averaged over land is ~1.7%/°C ocean mean surface air temperature increase, while the increase in PET is 5.3%/°C, leading to a decrease in P/PET (i.e., a drier terrestrial climate) by ~3.4%/°C. Noting a similar rate of percentage increase in P over land to that in evaporation (E) over ocean, we propose a framework for examining the change in P/PET, in which we compare the change in PET over land and E over ocean, both expressed using the Penman-Monteith formula. We show that a drier terrestrial climate is caused by (i) enhanced land warming relative to the ocean, (ii) a decrease in relative humidity over land but an increase over ocean, (iii) part of increase in net downward surface radiation going into the deep ocean, and (iv) different responses of PET over land and E over ocean for given changes in atmospheric conditions (largely associated with changes in temperatures). The relative contributions to the change in terrestrial mean aridity from these four factors are about 35%, 35%, 15%, and 15%, respectively. The slight slowdown of the surface wind over both land and ocean has little impact on the terrestrial mean aridity.

  10. Mesoamerican Nephropathy or Global Warming Nephropathy?

    PubMed

    Roncal-Jimenez, Carlos A; García-Trabanino, Ramon; Wesseling, Catharina; Johnson, Richard J

    2016-01-01

    An epidemic of chronic kidney disease (CKD) of unknown cause has emerged along the Pacific Coast of Central America. The disease primarily affects men working manually outdoors, and the major group affected is sugarcane workers. The disease presents with an asymptomatic rise in serum creatinine that progresses to end-stage renal disease over several years. Renal biopsies show chronic tubulointerstitial disease. While the cause remains unknown, recent studies suggest that it is driven by recurrent dehydration in the hot climate. Potential mechanisms include the development of hyperosmolarity with the activation of the aldose reductase-fructokinase pathway in the proximal tubule leading to local injury and inflammation, and the possibility that renal injury may be the consequence of repeated uricosuria and urate crystal formation as a consequence of both increased generation and urinary concentration, similar to a chronic tumor lysis syndrome. The epidemic is postulated to be increasing due to the effects of global warming. An epidemic of CKD has led to the death of more than 20,000 lives in Central America. The cause is unknown, but appears to be due to recurrent dehydration. Potential mechanisms for injury are renal damage as a consequence of recurrent hyperosmolarity and/or injury to the tubules from repeated episodes of uricosuria. The epidemic of CKD in Mesoamerica may be due to chronic recurrent dehydration as a consequence of global warming and working conditions. This entity may be one of the first major diseases attributed to climate change and the greenhouse effect. © 2016 S. Karger AG, Basel.

  11. Global warming, global research, and global governing

    SciTech Connect

    Preining, O.

    1997-12-31

    The anticipated dangers of Global Warming can be mitigated by reducing atmospheric greenhouse gas concentrations, especially CO{sub 2}. To reach acceptable, constant levels within the next couple of centuries it might be necessary to accept stabilization levels higher than present ones, The annual CO{sub 2} emissions must be reduced far below today`s values. This is a very important result of the models discussed in the 1995 IPCC report. However, any even very modest scenario for the future must take into account a substantial increase in the world population which might double during the 21st century, There is a considerable emission reduction potential of the industrialized world due to efficiency increase, However, the demand for energy services by the growing world population will, inspite of the availability of alternative energy resources, possibly lead to a net increase in fossil fuel consumption. If the climate models are right, and the science community believes they are, we will experience a global warming of the order of a couple of degrees over the next century; we have to live with it. To be prepared for the future it is essential for us to use new research techniques embracing not only the familiar fields of hard sciences but also social, educational, ethical and economic aspects, We must find a way to build up the essential intellectual capacities needed to deal with these kinds of general problems within all nations and all societies. But this is not Although, we also have to find the necessary dynamical and highly flexible structures for a global governing using tools such as the environmental regime. The first step was the Framework Convention On Climate Change, UN 1992; for resolution of questions regarding implementations the Conference of the Parties was established.

  12. Competitive advantage on a warming planet.

    PubMed

    Lash, Jonathan; Wellington, Fred

    2007-03-01

    Whether you're in a traditional smokestack industry or a "clean" business like investment banking, your company will increasingly feel the effects of climate change. Even people skeptical about global warming's dangers are recognizing that, simply because so many others are concerned, the phenomenon has wide-ranging implications. Investors already are discounting share prices of companies poorly positioned to compete in a warming world. Many businesses face higher raw material and energy costs as more and more governments enact policies placing a cost on emissions. Consumers are taking into account a company's environmental record when making purchasing decisions. There's also a burgeoning market in greenhouse gas emission allowances (the carbon market), with annual trading in these assets valued at tens of billions of dollars. Companies that manage and mitigate their exposure to the risks associated with climate change while seeking new opportunities for profit will generate a competitive advantage over rivals in a carbon-constrained future. This article offers a systematic approach to mapping and responding to climate change risks. According to Jonathan Lash and Fred Wellington of the World Resources Institute, an environmental think tank, the risks can be divided into six categories: regulatory (policies such as new emissions standards), products and technology (the development and marketing of climate-friendly products and services), litigation (lawsuits alleging environmental harm), reputational (how a company's environmental policies affect its brand), supply chain (potentially higher raw material and energy costs), and physical (such as an increase in the incidence of hurricanes). The authors propose a four-step process for responding to climate change risk: Quantify your company's carbon footprint; identify the risks and opportunities you face; adapt your business in response; and do it better than your competitors.

  13. Perihelion precession, polar ice and global warming

    NASA Astrophysics Data System (ADS)

    Steel, Duncan

    2013-03-01

    The increase in mean global temperature over the past 150 years is generally ascribed to human activities, in particular the rises in the atmospheric mixing ratios of carbon dioxide and other greenhouse gases since the Industrial Revolution began. Whilst it is thought that ice ages and interglacial periods are mainly initiated by multi-millennial variations in Earth's heliocentric orbit and obliquity, shorter-term orbital variations and consequent observable climatic effects over decadal/centurial timescales have not been considered significant causes of contemporary climate change compared to anthropogenic influences. Here it is shown that the precession of perihelion occurring over a century substantially affects the intra-annual variation of solar radiation influx at different locations, especially higher latitudes, with northern and southern hemispheres being subject to contrasting insolation changes. This north/south asymmetry has grown since perihelion was aligned with the winter solstice seven to eight centuries ago, and must cause enhanced year-on-year springtime melting of Arctic (but not Antarctic) ice and therefore feedback warming because increasing amounts of land and open sea are denuded of high-albedo ice and snow across boreal summer and into autumn. The accelerating sequence of insolation change now occurring as perihelion moves further into boreal winter has not occurred previously during the Holocene and so would not have been observed before by past or present civilisations. Reasons are given for the significance of this process having been overlooked until now. This mechanism represents a supplementary - natural - contribution to climate change in the present epoch and may even be the dominant fundamental cause of global warming, although anthropogenic effects surely play a role too.

  14. Spectral analysis of amazon canopy phenology during the dry season using a tower hyperspectral camera and modis observations

    DOE PAGES

    de Moura, Yhasmin Mendes; Galvão, Lênio Soares; Hilker, Thomas; ...

    2017-09-01

    The association between spectral reflectance and canopy processes remains challenging for quantifying large-scale canopy phenological cycles in tropical forests. In this paper, we used a tower-mounted hyperspectral camera in an eastern Amazon forest to assess how canopy spectral signals of three species are linked with phenological processes in the 2012 dry season. We explored different approaches to disentangle the spectral components of canopy phenology processes and analyze their variations over time using 17 images acquired by the camera. The methods included linear spectral mixture analysis (SMA); principal component analysis (PCA); continuum removal (CR); and first-order derivative analysis. In addition, threemore » vegetation indices potentially sensitive to leaf flushing, leaf loss and leaf area index (LAI) were calculated: the Enhanced Vegetation Index (EVI), Normalized Difference Vegetation Index (NDVI) and the entitled Green-Red Normalized Difference (GRND) index. We inspected also the consistency of the camera observations using Moderate Resolution Imaging Spectroradiometer (MODIS) and available phenological data on new leaf production and LAI of young, mature and old leaves simulated by a leaf demography-ontogeny model. The results showed a diversity of phenological responses during the 2012 dry season with related changes in canopy structure and greenness values. Because of the differences in timing and intensity of leaf flushing and leaf shedding, Erisma uncinatum, Manilkara huberi and Chamaecrista xinguensis presented different green vegetation (GV) and non-photosynthetic vegetation (NPV) SMA fractions; distinct PCA scores; changes in depth, width and area of the 681-nm chlorophyll absorption band; and variations over time in the EVI, GRND and NDVI. At the end of dry season, GV increased for Erisma uncinatum, while NPV increased for Chamaecrista xinguensis. For Manilkara huberi, the NPV first increased in the beginning of August and then decreased

  15. North Atlantic warming during Dansgaard-Oeschger events synchronous with Antarctic warming and out-of-phase with Greenland climate

    PubMed Central

    Rasmussen, Tine L.; Thomsen, Erik; Moros, Matthias

    2016-01-01

    The precise reason for the differences and out-of-phase relationship between the abrupt Dansgaard-Oeschger warmings in the Nordic seas and Greenland ice cores and the gradual warmings in the south-central Atlantic and Antarctic ice cores is poorly understood. Termed the bipolar seesaw, the differences are apparently linked to perturbations in the ocean circulation pattern. Here we show that surface and intermediate-depth water south of Iceland warmed gradually synchronously with the Antarctic warming and out of phase with the abrupt warming of the Nordic seas and over Greenland. The hinge line between areas showing abrupt and gradual warming was close to the Greenland-Scotland Ridge and the marine system appears to be a ‘push-and-pull’ system rather than a seesaw system. ‘Pull’ during the warm interstadials, when convection in the Nordic seas was active; ‘push’ during the cold stadials, when convection stopped and warm water from the south-central Atlantic pushed northward gradually warming the North Atlantic and Nordic seas. PMID:26847384

  16. North Atlantic warming during Dansgaard-Oeschger events synchronous with Antarctic warming and out-of-phase with Greenland climate.

    PubMed

    Rasmussen, Tine L; Thomsen, Erik; Moros, Matthias

    2016-02-05

    The precise reason for the differences and out-of-phase relationship between the abrupt Dansgaard-Oeschger warmings in the Nordic seas and Greenland ice cores and the gradual warmings in the south-central Atlantic and Antarctic ice cores is poorly understood. Termed the bipolar seesaw, the differences are apparently linked to perturbations in the ocean circulation pattern. Here we show that surface and intermediate-depth water south of Iceland warmed gradually synchronously with the Antarctic warming and out of phase with the abrupt warming of the Nordic seas and over Greenland. The hinge line between areas showing abrupt and gradual warming was close to the Greenland-Scotland Ridge and the marine system appears to be a 'push-and-pull' system rather than a seesaw system. 'Pull' during the warm interstadials, when convection in the Nordic seas was active; 'push' during the cold stadials, when convection stopped and warm water from the south-central Atlantic pushed northward gradually warming the North Atlantic and Nordic seas.

  17. How are large western hemisphere warm pools formed?

    NASA Astrophysics Data System (ADS)

    Enfield, David B.; Lee, Sang-Ki; Wang, Chunzai

    2006-08-01

    During the boreal summer the Western Hemisphere warm pool (WHWP) stretches from the eastern North Pacific to the tropical North Atlantic and is a key feature of the climate of the Americas and Africa. In the summers following nine El Niño events during 1950-2000, there have been five instances of extraordinarily large warm pools averaging about twice the climatological annual size. These large warm pools have induced a strengthened divergent circulation aloft and have been associated with rainfall anomalies throughout the western hemisphere tropics and subtropics and with more frequent hurricanes. However, following four other El Niño events large warm pools did not develop, such that the mere existence of El Niño during the boreal winter does not provide the basis for predicting an anomalously large warm pool the following summer. In this paper, we find consistency with the hypothesis that large warm pools result from an anomalous divergent circulation forced by sea surface temperature (SST) anomalies in the Pacific, the so-called atmospheric bridge. We also find significant explanations for why large warm pools do not always develop. If the El Niño event ends early in the eastern Pacific, the Pacific warm anomaly lacks the persistence needed to force the atmospheric bridge and the Atlantic portion of the warm pool remains normal. If SST anomalies in the eastern Pacific do not last much beyond February of the following year, then the eastern North Pacific portion of the warm pool remains normal. The overall strength of the Pacific El Niño does not appear to be a critical factor. We also find that when conditions favor a developing atmospheric bridge and the winter atmosphere over the North Atlantic conforms to a negative North Atlantic Oscillation (NAO) pattern (as in 1957-58 and 1968-69), the forcing is reinforced and the warm pool is stronger. On the other hand, if a positive NAO pattern develops the warm pool may remain normal even if other circumstances

  18. Human Milk Warming Temperatures Using a Simulation of Currently Available Storage and Warming Methods.

    PubMed

    Bransburg-Zabary, Sharron; Virozub, Alexander; Mimouni, Francis B

    2015-01-01

    Human milk handling guidelines are very demanding, based upon solid scientific evidence that handling methods can make a real difference in infant health and nutrition. Indeed, properly stored milk maintains many of its unique qualities and continues to be the second and third best infant feeding alternatives, much superior to artificial feeding. Container type and shape, mode of steering, amount of air exposure and storage temperature may adversely affect milk stability and composition. Heating above physiological temperatures significantly impacts nutritional and immunological properties of milk. In spite of this knowledge, there are no strict guidelines regarding milk warming. Human milk is often heated in electrical-based bottle warmers that can exceed 80°C, a temperature at which many beneficial human milk properties disappear. High temperatures can also induce fat profile variations as compared with fresh human milk. In this manuscript we estimate the amount of damage due to overheating during warming using a heat flow simulation of a regular water based bottle warmer. To do so, we carried out a series of warming simulations which provided us with dynamic temperature fields within bottled milk. We simulated the use of a hot water-bath at 80°C to heat bottled refrigerated milk (60 ml and 178 ml) to demonstrate that large milk portions are overheated (above 40°C). It seems that the contemporary storage method (upright feeding tool, i.e. bottle) and bottle warming device, are not optimize to preserve the unique properties of human milk. Health workers and parents should be aware of this problem especially when it relates to sick neonates and preemies that cannot be directly fed at the breast.

  19. Human Milk Warming Temperatures Using a Simulation of Currently Available Storage and Warming Methods

    PubMed Central

    Bransburg-Zabary, Sharron; Virozub, Alexander; Mimouni, Francis B.

    2015-01-01

    Human milk handling guidelines are very demanding, based upon solid scientific evidence that handling methods can make a real difference in infant health and nutrition. Indeed, properly stored milk maintains many of its unique qualities and continues to be the second and third best infant feeding alternatives, much superior to artificial feeding. Container type and shape, mode of steering, amount of air exposure and storage temperature may adversely affect milk stability and composition. Heating above physiological temperatures significantly impacts nutritional and immunological properties of milk. In spite of this knowledge, there are no strict guidelines regarding milk warming. Human milk is often heated in electrical-based bottle warmers that can exceed 80°C, a temperature at which many beneficial human milk properties disappear. High temperatures can also induce fat profile variations as compared with fresh human milk. In this manuscript we estimate the amount of damage due to overheating during warming using a heat flow simulation of a regular water based bottle warmer. To do so, we carried out a series of warming simulations which provided us with dynamic temperature fields within bottled milk. We simulated the use of a hot water-bath at 80°C to heat bottled refrigerated milk (60ml and 178 ml) to demonstrate that large milk portions are overheated (above 40°C). It seems that the contemporary storage method (upright feeding tool, i.e. bottle) and bottle warming device, are not optimize to preserve the unique properties of human milk. Health workers and parents should be aware of this problem especially when it relates to sick neonates and preemies that cannot be directly fed at the breast. PMID:26061694

  20. Continuously amplified warming in the Alaskan Arctic: Implications for estimating global warming hiatus

    NASA Astrophysics Data System (ADS)

    Wang, Kang; Zhang, Tingjun; Zhang, Xiangdong; Clow, Gary D.; Jafarov, Elchin E.; Overeem, Irina; Romanovsky, Vladimir; Peng, Xiaoqing; Cao, Bin

    2017-09-01

    Historically, in situ measurements have been notoriously sparse over the Arctic. As a consequence, the existing gridded data of surface air temperature (SAT) may have large biases in estimating the warming trend in this region. Using data from an expanded monitoring network with 31 stations in the Alaskan Arctic, we demonstrate that the SAT has increased by 2.19°C in this region, or at a rate of 0.23°C/decade during 1921-2015. Meanwhile, we found that the SAT warmed at 0.71°C/decade over 1998-2015, which is 2 to 3 times faster than the rate established from the gridded data sets. Focusing on the "hiatus" period 1998-2012 as identified by the Intergovernmental Panel on Climate Change (IPCC) report, the SAT has increased at 0.45°C/decade, which captures more than 90% of the regional trend for 1951-2012. We suggest that sparse in situ measurements are responsible for underestimation of the SAT change in the gridded data sets. It is likely that enhanced climate warming may also have happened in the other regions of the Arctic since the late 1990s but left undetected because of incomplete observational coverage.

  1. Design and performance of B4WarmED, an aboveground and belowground free-air warming experiment at the temperate-boreal forest ecotone

    USDA-ARS?s Scientific Manuscript database

    Conducting manipulative climate change experiments in forests is challenging, given their spatial heterogeneity and canopy complexity. One specific challenge involves warming both plants and soils to depth in ecosystems without much bare ground. We describe the design, implementation, and performanc...

  2. Seagrass ecophysiological performance under ocean warming and acidification

    NASA Astrophysics Data System (ADS)

    Repolho, Tiago; Duarte, Bernardo; Dionísio, Gisela; Paula, José Ricardo; Lopes, Ana R.; Rosa, Inês C.; Grilo, Tiago F.; Caçador, Isabel; Calado, Ricardo; Rosa, Rui

    2017-02-01

    Seagrasses play an essential ecological role within coastal habitats and their worldwide population decline has been linked to different types of anthropogenic forces. We investigated, for the first time, the combined effects of future ocean warming and acidification on fundamental biological processes of Zostera noltii, including shoot density, leaf coloration, photophysiology (electron transport rate, ETR; maximum PSII quantum yield, Fv/Fm) and photosynthetic pigments. Shoot density was severely affected under warming conditions, with a concomitant increase in the frequency of brownish colored leaves (seagrass die-off). Warming was responsible for a significant decrease in ETR and Fv/Fm (particularly under control pH conditions), while promoting the highest ETR variability (among experimental treatments). Warming also elicited a significant increase in pheophytin and carotenoid levels, alongside an increase in carotenoid/chlorophyll ratio and De-Epoxidation State (DES). Acidification significantly affected photosynthetic pigments content (antheraxanthin, β-carotene, violaxanthin and zeaxanthin), with a significant decrease being recorded under the warming scenario. No significant interaction between ocean acidification and warming was observed. Our findings suggest that future ocean warming will be a foremost determinant stressor influencing Z. noltii survival and physiological performance. Additionally, acidification conditions to occur in the future will be unable to counteract deleterious effects posed by ocean warming.

  3. Effects of Warm-Up Stretching Exercises on Sprint Performance

    ERIC Educational Resources Information Center

    Makaruk, Hubert; Makaruk, Beata; Kedra, Stanislaw

    2008-01-01

    Study aim: To assess direct effects of warm-up consisting of static and dynamic stretching exercises on sprint results attained by students differing in sprint performance. Material and methods: A group of 24 male and 19 female physical education students, including 12 and 9 sprinters, respectively. They performed warm-ups consisting of dynamic…

  4. Seagrass ecophysiological performance under ocean warming and acidification.

    PubMed

    Repolho, Tiago; Duarte, Bernardo; Dionísio, Gisela; Paula, José Ricardo; Lopes, Ana R; Rosa, Inês C; Grilo, Tiago F; Caçador, Isabel; Calado, Ricardo; Rosa, Rui

    2017-02-01

    Seagrasses play an essential ecological role within coastal habitats and their worldwide population decline has been linked to different types of anthropogenic forces. We investigated, for the first time, the combined effects of future ocean warming and acidification on fundamental biological processes of Zostera noltii, including shoot density, leaf coloration, photophysiology (electron transport rate, ETR; maximum PSII quantum yield, Fv/Fm) and photosynthetic pigments. Shoot density was severely affected under warming conditions, with a concomitant increase in the frequency of brownish colored leaves (seagrass die-off). Warming was responsible for a significant decrease in ETR and Fv/Fm (particularly under control pH conditions), while promoting the highest ETR variability (among experimental treatments). Warming also elicited a significant increase in pheophytin and carotenoid levels, alongside an increase in carotenoid/chlorophyll ratio and De-Epoxidation State (DES). Acidification significantly affected photosynthetic pigments content (antheraxanthin, β-carotene, violaxanthin and zeaxanthin), with a significant decrease being recorded under the warming scenario. No significant interaction between ocean acidification and warming was observed. Our findings suggest that future ocean warming will be a foremost determinant stressor influencing Z. noltii survival and physiological performance. Additionally, acidification conditions to occur in the future will be unable to counteract deleterious effects posed by ocean warming.

  5. Situational Influences upon Children's Beliefs about Global Warming and Energy

    ERIC Educational Resources Information Center

    Devine-Wright, Patrick; Devine-Wright, Hannah; Fleming, Paul

    2004-01-01

    This paper explores children's beliefs about global warming and energy sources from a psychological perspective, focusing upon situational influences upon subjective beliefs, including perceived self-efficacy. The context of the research is one of growing concern at the potential impacts of global warming, yet demonstrably low levels of…

  6. Possible dynamical mechanisms for the Martian polar warming phenomenon

    NASA Technical Reports Server (NTRS)

    Barnes, Jeffrey R.

    1987-01-01

    The research performed under NASA contract NAGW-727 falls into three major categories, i.e., dynamical modeling of the Martian polar warming phenomenon, studies of dust and water transport associated with a Martian polar warming, and studies of the possible effects of breaking gravity waves on the Martian atmospheric circulation. The work carried out in each of these areas is summarized.

  7. Seagrass ecophysiological performance under ocean warming and acidification

    PubMed Central

    Repolho, Tiago; Duarte, Bernardo; Dionísio, Gisela; Paula, José Ricardo; Lopes, Ana R.; Rosa, Inês C.; Grilo, Tiago F.; Caçador, Isabel; Calado, Ricardo; Rosa, Rui

    2017-01-01

    Seagrasses play an essential ecological role within coastal habitats and their worldwide population decline has been linked to different types of anthropogenic forces. We investigated, for the first time, the combined effects of future ocean warming and acidification on fundamental biological processes of Zostera noltii, including shoot density, leaf coloration, photophysiology (electron transport rate, ETR; maximum PSII quantum yield, Fv/Fm) and photosynthetic pigments. Shoot density was severely affected under warming conditions, with a concomitant increase in the frequency of brownish colored leaves (seagrass die-off). Warming was responsible for a significant decrease in ETR and Fv/Fm (particularly under control pH conditions), while promoting the highest ETR variability (among experimental treatments). Warming also elicited a significant increase in pheophytin and carotenoid levels, alongside an increase in carotenoid/chlorophyll ratio and De-Epoxidation State (DES). Acidification significantly affected photosynthetic pigments content (antheraxanthin, β-carotene, violaxanthin and zeaxanthin), with a significant decrease being recorded under the warming scenario. No significant interaction between ocean acidification and warming was observed. Our findings suggest that future ocean warming will be a foremost determinant stressor influencing Z. noltii survival and physiological performance. Additionally, acidification conditions to occur in the future will be unable to counteract deleterious effects posed by ocean warming. PMID:28145531

  8. Native temperature regime influences soil response to simulated warming

    Treesearch

    Timothy G. Whitby; Michael D. Madritch

    2013-01-01

    Anthropogenic climate change is expected to increase global temperatures and potentially increase soil carbon (C) mineralization, which could lead to a positive feedback between global warming and soil respiration. However the magnitude and spatial variability of belowground responses to warming are not yet fully understood. Some of the variability may depend...

  9. Decomposition of recalcitrant carbon under experimental warming in boreal forest

    PubMed Central

    Allison, Steven D.; Treseder, Kathleen K.

    2017-01-01

    Over the long term, soil carbon (C) storage is partly determined by decomposition rate of carbon that is slow to decompose (i.e., recalcitrant C). According to thermodynamic theory, decomposition rates of recalcitrant C might differ from those of non-recalcitrant C in their sensitivities to global warming. We decomposed leaf litter in a warming experiment in Alaskan boreal forest, and measured mass loss of recalcitrant C (lignin) vs. non-recalcitrant C (cellulose, hemicellulose, and sugars) throughout 16 months. We found that these C fractions responded differently to warming. Specifically, after one year of decomposition, the ratio of recalcitrant C to non-recalcitrant C remaining in litter declined in the warmed plots compared to control. Consistent with this pattern, potential activities of enzymes targeting recalcitrant C increased with warming, relative to those targeting non-recalcitrant C. Even so, mass loss of individual C fractions showed that non-recalcitrant C is preferentially decomposed under control conditions whereas recalcitrant C losses remain unchanged between control and warmed plots. Moreover, overall mass loss was greater under control conditions. Our results imply that direct warming effects, as well as indirect warming effects (e.g. drying), may serve to maintain decomposition rates of recalcitrant C compared to non-recalcitrant C despite negative effects on overall decomposition. PMID:28622366

  10. Artificial warming of arctic meadow under pollution stress: Experimental design

    USDA-ARS?s Scientific Manuscript database

    Boreal and arctic terrestrial ecosystems are central to the climate change debate, notably because future warming is expected to be disproportionate as compared to world averages. Likewise, greenhouse gas (GHG) release from terrestrial ecosystems exposed to climate warming is expected to be the larg...

  11. Soil warming, carbon-nitrogen interactions, and forest carbon budgets.

    PubMed

    Melillo, Jerry M; Butler, Sarah; Johnson, Jennifer; Mohan, Jacqueline; Steudler, Paul; Lux, Heidi; Burrows, Elizabeth; Bowles, Francis; Smith, Rose; Scott, Lindsay; Vario, Chelsea; Hill, Troy; Burton, Andrew; Zhou, Yu-Mei; Tang, Jim

    2011-06-07

    Soil warming has the potential to alter both soil and plant processes that affect carbon storage in forest ecosystems. We have quantified these effects in a large, long-term (7-y) soil-warming study in a deciduous forest in New England. Soil warming has resulted in carbon losses from the soil and stimulated carbon gains in the woody tissue of trees. The warming-enhanced decay of soil organic matter also released enough additional inorganic nitrogen into the soil solution to support the observed increases in plant carbon storage. Although soil warming has resulted in a cumulative net loss of carbon from a New England forest relative to a control area over the 7-y study, the annual net losses generally decreased over time as plant carbon storage increased. In the seventh year, warming-induced soil carbon losses were almost totally compensated for by plant carbon gains in response to warming. We attribute the plant gains primarily to warming-induced increases in nitrogen availability. This study underscores the importance of incorporating carbon-nitrogen interactions in atmosphere-ocean-land earth system models to accurately simulate land feedbacks to the climate system.

  12. Soil warming, carbon–nitrogen interactions, and forest carbon budgets

    PubMed Central

    Melillo, Jerry M.; Butler, Sarah; Johnson, Jennifer; Mohan, Jacqueline; Steudler, Paul; Lux, Heidi; Burrows, Elizabeth; Bowles, Francis; Smith, Rose; Scott, Lindsay; Vario, Chelsea; Hill, Troy; Burton, Andrew; Zhou, Yu-Mei; Tang, Jim

    2011-01-01

    Soil warming has the potential to alter both soil and plant processes that affect carbon storage in forest ecosystems. We have quantified these effects in a large, long-term (7-y) soil-warming study in a deciduous forest in New England. Soil warming has resulted in carbon losses from the soil and stimulated carbon gains in the woody tissue of trees. The warming-enhanced decay of soil organic matter also released enough additional inorganic nitrogen into the soil solution to support the observed increases in plant carbon storage. Although soil warming has resulted in a cumulative net loss of carbon from a New England forest relative to a control area over the 7-y study, the annual net losses generally decreased over time as plant carbon storage increased. In the seventh year, warming-induced soil carbon losses were almost totally compensated for by plant carbon gains in response to warming. We attribute the plant gains primarily to warming-induced increases in nitrogen availability. This study underscores the importance of incorporating carbon–nitrogen interactions in atmosphere–ocean–land earth system models to accurately simulate land feedbacks to the climate system. PMID:21606374

  13. Waste Reduction Model (WARM) Resources for Small Businesses and Organizations

    EPA Pesticide Factsheets

    This page provides a brief overview of how EPA’s Waste Reduction Model (WARM) can be used by small businesses and organizations. The page includes a brief summary of uses of WARM for the audience and links to other resources.

  14. Situational Influences upon Children's Beliefs about Global Warming and Energy

    ERIC Educational Resources Information Center

    Devine-Wright, Patrick; Devine-Wright, Hannah; Fleming, Paul

    2004-01-01

    This paper explores children's beliefs about global warming and energy sources from a psychological perspective, focusing upon situational influences upon subjective beliefs, including perceived self-efficacy. The context of the research is one of growing concern at the potential impacts of global warming, yet demonstrably low levels of…

  15. Opposing plant community responses to warming with and without herbivores.

    PubMed

    Post, Eric; Pedersen, Christian

    2008-08-26

    If controls over primary productivity and plant community composition are mainly environmental, as opposed to biological, then global change may result in large-scale alterations in ecosystem structure and function. This view appears to be favored among investigations of plant biomass and community responses to experimental and observed warming. In far northern and arctic ecosystems, such studies predict increasing dominance of woody shrubs with future warming and emphasize the carbon (C)-sequestration potential and consequent atmospheric feedback potential of such responses. In contrast to previous studies, we incorporated natural herbivory by muskoxen and caribou into a 5-year experimental investigation of arctic plant community response to warming. In accordance with other studies, warming increased total community biomass by promoting growth of deciduous shrubs (dwarf birch and gray willow). However, muskoxen and caribou reduced total community biomass response, and responses of birch and willow, to warming by 19%, 46%, and 11%, respectively. Furthermore, under warming alone, the plant community shifted after 5 years away from graminoid-dominated toward dwarf birch-dominated. In contrast, where herbivores grazed, plant community composition on warmed plots did not differ from that on ambient plots after 5 years. These results highlight the potentially important and overlooked influences of vertebrate herbivores on plant community response to warming and emphasize that conservation and management of large herbivores may be an important component of mitigating ecosystem response to climate change.

  16. Opposing plant community responses to warming with and without herbivores

    PubMed Central

    Post, Eric; Pedersen, Christian

    2008-01-01

    If controls over primary productivity and plant community composition are mainly environmental, as opposed to biological, then global change may result in large-scale alterations in ecosystem structure and function. This view appears to be favored among investigations of plant biomass and community responses to experimental and observed warming. In far northern and arctic ecosystems, such studies predict increasing dominance of woody shrubs with future warming and emphasize the carbon (C)-sequestration potential and consequent atmospheric feedback potential of such responses. In contrast to previous studies, we incorporated natural herbivory by muskoxen and caribou into a 5-year experimental investigation of arctic plant community response to warming. In accordance with other studies, warming increased total community biomass by promoting growth of deciduous shrubs (dwarf birch and gray willow). However, muskoxen and caribou reduced total community biomass response, and responses of birch and willow, to warming by 19%, 46%, and 11%, respectively. Furthermore, under warming alone, the plant community shifted after 5 years away from graminoid-dominated toward dwarf birch-dominated. In contrast, where herbivores grazed, plant community composition on warmed plots did not differ from that on ambient plots after 5 years. These results highlight the potentially important and overlooked influences of vertebrate herbivores on plant community response to warming and emphasize that conservation and management of large herbivores may be an important component of mitigating ecosystem response to climate change. PMID:18719116

  17. Decomposition of recalcitrant carbon under experimental warming in boreal forest.

    PubMed

    Romero-Olivares, Adriana L; Allison, Steven D; Treseder, Kathleen K

    2017-01-01

    Over the long term, soil carbon (C) storage is partly determined by decomposition rate of carbon that is slow to decompose (i.e., recalcitrant C). According to thermodynamic theory, decomposition rates of recalcitrant C might differ from those of non-recalcitrant C in their sensitivities to global warming. We decomposed leaf litter in a warming experiment in Alaskan boreal forest, and measured mass loss of recalcitrant C (lignin) vs. non-recalcitrant C (cellulose, hemicellulose, and sugars) throughout 16 months. We found that these C fractions responded differently to warming. Specifically, after one year of decomposition, the ratio of recalcitrant C to non-recalcitrant C remaining in litter declined in the warmed plots compared to control. Consistent with this pattern, potential activities of enzymes targeting recalcitrant C increased with warming, relative to those targeting non-recalcitrant C. Even so, mass loss of individual C fractions showed that non-recalcitrant C is preferentially decomposed under control conditions whereas recalcitrant C losses remain unchanged between control and warmed plots. Moreover, overall mass loss was greater under control conditions. Our results imply that direct warming effects, as well as indirect warming effects (e.g. drying), may serve to maintain decomposition rates of recalcitrant C compared to non-recalcitrant C despite negative effects on overall decomposition.

  18. Choral Warm-ups: Preparation To Sing, Listen, and Learn.

    ERIC Educational Resources Information Center

    Stegman, Sandra Frey

    2003-01-01

    Focuses on creating warm-up exercises for use with choral groups, offering tips for developing the exercises. Explains that a warm-up is useful for teaching students to sing, listen, and learn specific music concepts and activities. Provides a list of additional resources and example activities. (CMK)

  19. Resonance Absorption of Laser Light by Warm and Cold Plasmas.

    DTIC Science & Technology

    1981-03-01

    34 Ponderomotive Force................38 Hot Electron Energy ................40 Validity bf Assumptions..............41 V. Conclusions...Indicated by Arrows) for the Warm and Cold Plasma Models ..... ................ 31 7 Cold Plasma: Fraction of Laser Energy Resonantly Absorbed as a...Function of Incident Angle .. ............ 35 8 Warm Plasma: Fraction of Laser Energy Resonantly Absorbed as a Function of Incident Angle (T = 637 ev and

  20. Results of Sextant Warm-Up Transient Analysis

    SciTech Connect

    Rank, J.

    1994-06-24

    RHIC design criteria dictates that for the purposes of component repair or replacement a sextant be warmed from it operating temperature to a serviceable temperature in approximately 24 hours. This warming will be accomplished by means of two integral electric heating circuits which loop back through every ~30 m of the magnet.

  1. Effects of Warm-Up Stretching Exercises on Sprint Performance

    ERIC Educational Resources Information Center

    Makaruk, Hubert; Makaruk, Beata; Kedra, Stanislaw

    2008-01-01

    Study aim: To assess direct effects of warm-up consisting of static and dynamic stretching exercises on sprint results attained by students differing in sprint performance. Material and methods: A group of 24 male and 19 female physical education students, including 12 and 9 sprinters, respectively. They performed warm-ups consisting of dynamic…

  2. An aftereffect of global warming on tropical Pacific decadal variability

    NASA Astrophysics Data System (ADS)

    Zheng, Jian; Liu, Qinyu; Wang, Chuanyang

    2017-05-01

    Studies have shown that global warming over the past six decades can weaken the tropical Pacific Walker circulation and maintain the positive phase of the Interdecadal Pacific Oscillation (IPO). Based on observations and model simulations, another aftereffect of global warming on IPO is found. After removing linear trends (global warming signals) from observations, however, the tropical Pacific climate still exhibited some obvious differences between two IPO negative phases. The boreal winter (DJF) equatorial central-eastern Pacific sea surface temperature (SST) was colder during the 1999-2014 period (P2) than that during 1961-1976 (P1). This difference may have been a result of global warming nonlinear modulation of precipitation; i.e., in the climatological rainy region, the core area of the tropical Indo-western Pacific warm pool receives more precipitation through the "wet-get-wetter" mechanism. Positive precipitation anomalies in the warm pool during P2 are much stronger than those during P1, even after subtracting the linear trend. Corresponding to the differences of precipitation, the Pacific Walker circulation is stronger in P2 than in P1. Consequent easterly winds over the equatorial Pacific led to a colder equatorial eastern-central Pacific during P2. Therefore, tropical Pacific climate differences between the two negative IPO phases are aftereffects of global warming. These aftereffects are supported by the results of coupled climate model experiments, with and without global warming.

  3. Evaluation of the Warm Springs Career Exploration Project.

    ERIC Educational Resources Information Center

    Owens, Thomas R.

    The Warm Springs Career Exploration Project (WSCEP) is an adaptation of experience-based career education (EBCE) for Native Americans residing on the Warm Springs Indian Reservation. The project served as a full-time program for American Indian students aged 16-19 who had dropped out of school, and also served as a part-time career development…

  4. Gradual Warming in the North Atlantic during D-O Events Synchronous with Antarctic and Southern Hemisphere Warmings

    NASA Astrophysics Data System (ADS)

    Rasmussen, T. L.; Thomsen, E.; Moros, M.

    2016-12-01

    The climate of the last glacial period was interrupted by about 25 rapid oscillations, called Dansgaard-Oeschger events. In the Greenland ice cores, the events consist of an abrupt warming to warm interstadial conditions followed by a more gradual return to cold stadial conditions. Similar abrupt warmings are seen in paleoceanographic proxies from the Nordic seas, and the shifts are apparently linked to perturbations in the ocean thermohaline circulation. The events also occur in the Antarctic ice cores, but the amplitudes here are smaller and the warmings are more gradual and initiated earlier than in the north. The out-of-phase relationship between the north and south is often referred to as the `Bipolar seesaw'. We have studied core SO2 from the Reykjanes Ridge in the central northernmost Atlantic. The results are compared with previously published records from the North Atlantic and correlated with the Greenland and Antarctic ice cores. By means of transfer function analysis and δ18O values from planktic and benthic foraminifera we show that surface and bottom water temperatures in SO2 increased gradually during the Greenland stadials to a maximum at the beginning of the interstadials. The warmings in SO2 follow the timing and gradual warmings observed in the Antarctic ice cores and they are clearly out of phase with the abrupt, delayed warmings over Greenland. Apparently, the surface and intermediate water over most of the Atlantic from the Antarctica to the Scotland-Greenland Ridge warmed and pressed northward at a time when the atmospheric temperatures over Greenland were at minimum and the convection in the Nordic seas stopped. The system appears to function more as a `push-and-pull' system than as a seesaw with a `pull' during the warm interstadials, when convection in the Nordic seas was active and a `push' during the cold stadials, when warm water from the south-central Atlantic pushed northward gradually warming the northernmost Atlantic and Nordic

  5. Active perioperative patient warming using a self-warming blanket (BARRIER EasyWarm) is superior to passive thermal insulation: a multinational, multicenter, randomized trial.

    PubMed

    Torossian, Alexander; Van Gerven, Elke; Geertsen, Karin; Horn, Bengt; Van de Velde, Marc; Raeder, Johan

    2016-11-01

    Incidence of inadvertent perioperative hypothermia is still high; therefore, present guidelines advocate "prewarming" for its prevention. Prewarming means preoperative patient skin warming, which minimizes redistribution hypothermia caused by induction of anesthesia. In this study, we compared the new self-warming BARRIER EasyWarm blanket with passive thermal insulation regarding mean perioperative patient core body temperature. Multinational, multicenter randomized prospective open-label controlled trial. Surgical ward, operation room, postanesthesia care unit at 4 European hospitals. A total of 246 adult patients, American Society of Anesthesiologists class I to III undergoing elective orthopedic; gynecologic; or ear, nose, and throat surgery scheduled for 30 to 120 minutes under general anesthesia. Patients received warmed hospital cotton blankets (passive thermal insulation, control group) or BARRIER EasyWarm blanket at least 30 minutes before induction of general anesthesia and throughout the perioperative period (intervention group). The primary efficacy outcome was the perioperative mean core body temperature measured by a tympanic infrared thermometer. Secondary outcomes were hypothermia incidence, change in core body temperature, length of stay in postanesthesia care unit, thermal comfort, patient satisfaction, ease of use, and adverse events related to the BARRIER EasyWarm blanket. The BARRIER EasyWarm blanket significantly improved perioperative core body temperature compared with standard hospital blankets (36.5°C, SD 0.4°C, vs 36.3, SD 0.3°C; P<.001). Intraoperatively, in the intervention group, hypothermia incidence was 38% compared with 60% in the control group (P=.001). Postoperatively, the figures were 24% vs 49%, respectively (P=.001). Patients in the intervention group had significantly higher thermal comfort scores, preoperatively and postoperatively. No serious adverse effects were observed in either group. Perioperative use of the new self-warming

  6. Recent warming at Summit, Greenland: Global context and implications

    NASA Astrophysics Data System (ADS)

    McGrath, Daniel; Colgan, William; Bayou, Nicolas; Muto, Atsuhiro; Steffen, Konrad

    2013-05-01

    at Summit, Greenland suggest that the annual mean near-surface air temperature increased at 0.09 ± 0.01°C/a over the 1982-2011 climatology period. This rate of warming, six times the global average, places Summit in the 99th percentile of all globally observed warming trends over this period. The rate of warming at Summit is increasing over time. During the instrumental period (1987-2011), warming has been greatest in the winter season, although the implications of summer warming are more acute. The annual maximum elevation of the equilibrium line and dry snow line has risen at 44 and 35 m/a over the past 15 and 18 years, respectively. Extrapolation of this observed trend now suggests, with 95% confidence intervals, that the dry snow facies of the Greenland Ice Sheet will inevitably transition to percolation facies. There is a 50% probability of this transition occurring by 2025.

  7. Warming modifies trophic cascades and eutrophication in experimental freshwater communities.

    PubMed

    Kratina, Pavel; Greig, Hamish S; Thompson, Patrick L; Carvalho-Pereira, Ticiana S A; Shurin, Jonathan B

    2012-06-01

    Climate warming is occurring in concert with other anthropogenic changes to ecosystems. However, it is unknown whether and how warming alters the importance of top-down vs. bottom-up control over community productivity and variability. We performed a 16-month factorial experimental manipulation of warming, nutrient enrichment, and predator presence in replicated freshwater pond mesocosms to test their independent and interactive impacts. Warming strengthened trophic cascades from fish to primary producers, and it decreased the impact of eutrophication on the mean and temporal variation of phytoplankton biomass. These impacts varied seasonally, with higher temperatures leading to stronger trophic cascades in winter and weaker algae blooms under eutrophication in summer. Our results suggest that higher temperatures may shift the control of primary production in freshwater ponds toward stronger top-down and weaker bottom-up effects. The dampened temporal variability of algal biomass under eutrophication at higher temperatures suggests that warming may stabilize some ecosystem processes.

  8. Effects of sea surface warming on marine plankton.

    PubMed

    Lewandowska, Aleksandra M; Boyce, Daniel G; Hofmann, Matthias; Matthiessen, Birte; Sommer, Ulrich; Worm, Boris

    2014-05-01

    Ocean warming has been implicated in the observed decline of oceanic phytoplankton biomass. Some studies suggest a physical pathway of warming via stratification and nutrient flux, and others a biological effect on plankton metabolic rates; yet the relative strength and possible interaction of these mechanisms remains unknown. Here, we implement projections from a global circulation model in a mesocosm experiment to examine both mechanisms in a multi-trophic plankton community. Warming treatments had positive direct effects on phytoplankton biomass, but these were overcompensated by the negative effects of decreased nutrient flux. Zooplankton switched from phytoplankton to grazing on ciliates. These results contrast with previous experiments under nutrient-replete conditions, where warming indirectly reduced phytoplankton biomass via increased zooplankton grazing. We conclude that the effect of ocean warming on marine plankton depends on the nutrient regime, and provide a mechanistic basis for understanding global change in marine ecosystems.

  9. Paleoanalogues of global warming in the 21st century

    NASA Astrophysics Data System (ADS)

    Velichko, A. A.; Borisova, O. K.

    2011-05-01

    On the basis of landscape-climatic reconstructions for warming periods in the past, likely scenarios of future global warming have been developed for various warming levels that might be reached during the current century. The paleoanalogue of global warming by 0.7-1°C is the Holocene climatic optimum (5.5-6 ka B.P.) and that by 1.7-2°C is the last interglacial optimum (about 125 ka B.P.). The complex analysis concerning response of the principal ecosystem components to the expected warming signifies that there will not be any shifts of vegetation zones during the 21st century; reconstruction will touch only the internal structure of vegetable associations and broadening of interzonal ecotones.

  10. Tracking ocean heat uptake during the surface warming hiatus

    PubMed Central

    Liu, Wei; Xie, Shang-Ping; Lu, Jian

    2016-01-01

    Ocean heat uptake is observed to penetrate deep into the Atlantic and Southern Oceans during the recent hiatus of global warming. Here we show that the deep heat penetration in these two basins is not unique to the hiatus but is characteristic of anthropogenic warming and merely reflects the depth of the mean meridional overturning circulation in the basin. We find, however, that heat redistribution in the upper 350 m between the Pacific and Indian Oceans is closely tied to the surface warming hiatus. The Indian Ocean shows an anomalous warming below 50 m during hiatus events due to an enhanced heat transport by the Indonesian throughflow in response to the intensified trade winds in the equatorial Pacific. Thus, the Pacific and Indian Oceans are the key regions to track ocean heat uptake during the surface warming hiatus. PMID:27025666

  11. Tracking ocean heat uptake during the surface warming hiatus.

    PubMed

    Liu, Wei; Xie, Shang-Ping; Lu, Jian

    2016-03-30

    Ocean heat uptake is observed to penetrate deep into the Atlantic and Southern Oceans during the recent hiatus of global warming. Here we show that the deep heat penetration in these two basins is not unique to the hiatus but is characteristic of anthropogenic warming and merely reflects the depth of the mean meridional overturning circulation in the basin. We find, however, that heat redistribution in the upper 350 m between the Pacific and Indian Oceans is closely tied to the surface warming hiatus. The Indian Ocean shows an anomalous warming below 50 m during hiatus events due to an enhanced heat transport by the Indonesian throughflow in response to the intensified trade winds in the equatorial Pacific. Thus, the Pacific and Indian Oceans are the key regions to track ocean heat uptake during the surface warming hiatus.

  12. Water Availability in a Warming World

    NASA Astrophysics Data System (ADS)

    Aminzade, Jennifer

    As climate warms during the 21st century, the resultant changes in water availability are a vital issue for society, perhaps even more important than the magnitude of warming itself. Yet our climate models disagree in their forecasts of water availability, limiting our ability to plan accordingly. This thesis investigates future water availability projections from Coupled Ocean-Atmosphere General Circulation Models (GCMs), primarily using two water availability measures: soil moisture and the Supply Demand Drought Index (SDDI). Chapter One introduces methods of measuring water availability and explores some of the fundamental differences between soil moisture, SDDI and the Palmer Drought Severity Index (PDSI). SDDI and PDSI tend to predict more severe future drought conditions than soil moisture; 21st century projections of SDDI show conditions rivaling North American historic mega-droughts. We compare multiple potential evapotranspiration (EP) methods in New York using input from the GISS Model ER GCM and local station data from Rochester, NY, and find that they compare favorably with local pan evaporation measurements. We calculate SDDI and PDSI values using various EP methods, and show that changes in future projections are largest when using EP methods most sensitive to global warming, not necessarily methods producing EP values with the largest magnitudes. Chapter Two explores the characteristics and biases of the five GCMs and their 20th and 21st century climate projections. We compare atmospheric variables that drive water availability changes globally, zonally, and geographically among models. All models show increases in both dry and wet extremes for SDDI and soil moisture, but increases are largest for extreme drying conditions using SDDI. The percentage of gridboxes that agree on the sign of change of soil moisture and SDDI between models is very low, but does increase in the 21st century. Still, differences between models are smaller than differences

  13. Phenology and global warming research in Brazil

    NASA Astrophysics Data System (ADS)

    Morellato, L. P. C.

    2009-04-01

    A recent review on South American phenology research has shown an increase in phenology papers over the last two decades, especially in this new 21st century. Nevertheless, there is a lack of long term data sets or monitoring systems, or of papers addressing plant phenology and global warming. The IPCC AR4 report from 2007 has offered indisputable evidence of regional to global-scale change in seasonality, but it is supported by plant and animal phenological data from North Hemisphere and temperate species. Information from tropical regions in general and South America in particular are sparse or lacking. Here I summarize the recent outcomes of our ongoing tropical phenology research in Brazil and its potential contribution to integrate fields and understand the effects of global warming within the tropics. The Phenology Laboratory (UNESP) is located at Rio Claro, São Paulo State, Southeastern Brazil. We are looking for trends and shifts on tropical vegetation phenology, and are exploring different methods for collecting and analyzing phenology data. The phenological studies are developed in collaboration with graduate and undergraduate students, post-docs and researchers from Brazil and around the world. We established three long term monitoring programs on Southeastern Brazil from 2000 onwards: trees from an urban garden, semideciduous forest trees, and savanna cerrado woody vegetation, all based on direct weekly to monthly observation of marked plants. We have collected some discontinuous data from Atlantic rain forest trees ranging from 5 to 8 years long. I collaborate with the longest tropical wet forest phenology monitoring system in Central Amazon, and with another long term monitoring system on semi deciduous forest from South Brazil. All research programs aim, in the long run, to monitor and detect shifts on tropical plant phenology related to climatic changes. Our first preliminary findings suggest that: (i) flowering and leafing are more affected by

  14. Global Warming and 21st Century Drying

    NASA Technical Reports Server (NTRS)

    Cook, Benjamin I.; Smerdun, Jason E.; Seager, Richard; Coats, Sloan

    2014-01-01

    Global warming is expected to increase the frequency and intensity of droughts in the twenty-first century, but the relative contributions from changes in moisture supply (precipitation) versus evaporative demand (potential evapotranspiration; PET) have not been comprehensively assessed. Using output from a suite of general circulation model (GCM) simulations from phase 5 of the Coupled Model Intercomparison Project, projected twentyfirst century drying and wetting trends are investigated using two offline indices of surface moisture balance: the Palmer Drought Severity Index (PDSI) and the Standardized Precipitation Evapotranspiration Index (SPEI). PDSI and SPEI projections using precipitation and Penman- Monteith based PET changes from the GCMs generally agree, showing robust cross-model drying in western North America, Central America, the Mediterranean, southern Africa, and the Amazon and robust wetting occurring in the Northern Hemisphere high latitudes and east Africa (PDSI only). The SPEI is more sensitive to PET changes than the PDSI, especially in arid regions such as the Sahara and Middle East. Regional drying and wetting patterns largely mirror the spatially heterogeneous response of precipitation in the models, although drying in the PDSI and SPEI calculations extends beyond the regions of reduced precipitation. This expansion of drying areas is attributed to globally widespread increases in PET, caused by increases in surface net radiation and the vapor pressure deficit. Increased PET not only intensifies drying in areas where precipitation is already reduced, it also drives areas into drought that would otherwise experience little drying or even wetting from precipitation trends alone. This PET amplification effect is largest in the Northern Hemisphere mid-latitudes, and is especially pronounced in western North America, Europe, and southeast China. Compared to PDSI projections using precipitation changes only, the projections incorporating both

  15. Global Warming and Its Health Impact.

    PubMed

    Rossati, Antonella

    2017-01-01

    Since the mid-19th century, human activities have increased greenhouse gases such as carbon dioxide, methane, and nitrous oxide in the Earth's atmosphere that resulted in increased average temperature. The effects of rising temperature include soil degradation, loss of productivity of agricultural land, desertification, loss of biodiversity, degradation of ecosystems, reduced fresh-water resources, acidification of the oceans, and the disruption and depletion of stratospheric ozone. All these have an impact on human health, causing non-communicable diseases such as injuries during natural disasters, malnutrition during famine, and increased mortality during heat waves due to complications in chronically ill patients. Direct exposure to natural disasters has also an impact on mental health and, although too complex to be quantified, a link has even been established between climate and civil violence. Over time, climate change can reduce agricultural resources through reduced availability of water, alterations and shrinking arable land, increased pollution, accumulation of toxic substances in the food chain, and creation of habitats suitable to the transmission of human and animal pathogens. People living in low-income countries are particularly vulnerable. Climate change scenarios include a change in distribution of infectious diseases with warming and changes in outbreaks associated with weather extreme events. After floods, increased cases of leptospirosis, campylobacter infections and cryptosporidiosis are reported. Global warming affects water heating, rising the transmission of water-borne pathogens. Pathogens transmitted by vectors are particularly sensitive to climate change because they spend a good part of their life cycle in a cold-blooded host invertebrate whose temperature is similar to the environment. A warmer climate presents more favorable conditions for the survival and the completion of the life cycle of the vector, going as far as to speed it up

  16. Warm gas accretion onto the Galaxy

    NASA Astrophysics Data System (ADS)

    Bland-Hawthorn, J.

    2009-03-01

    We present evidence that the accretion of warm gas onto the Galaxy today is at least as important as cold gas accretion. For more than a decade, the source of the bright Hα emission (up to 750 mR†) along the Magellanic Stream has remained a mystery. We present a hydrodynamical model that explains the known properties of the Hα emission and provides new insights on the lifetime of the Stream clouds. The upstream clouds are gradually disrupted due to their interaction with the hot halo gas. The clouds that follow plough into gas ablated from the upstream clouds, leading to shock ionisation at the leading edges of the downstream clouds. Since the following clouds also experience ablation, and weaker Hα (100-200 mR) is quite extensive, a disruptive cascade must be operating along much of the Stream. In order to light up much of the Stream as observed, it must have a small angle of attack (≈ 20°) to the halo, and this may already find support in new Hi observations. Another prediction is that the Balmer ratio (Hα/Hβ) will be substantially enhanced due to the slow shock; this will soon be tested by upcoming WHAM observations in Chile. We find that the clouds are evolving on timescales of 100-200 Myr, such that the Stream must be replenished by the Magellanic Clouds at a fairly constant rate (≳ 0.1 M⊙ yr-1). The ablated material falls onto the Galaxy as a warm drizzle; diffuse ionized gas at 104 K is an important constituent of galactic accretion. The observed Hα emission provides a new constraint on the rate of disruption of the Stream and, consequently, the infall rate of metal-poor gas onto the Galaxy. We consider the stability of Hi clouds falling towards the Galactic disk and show that most of these must break down into smaller fragments that become partially ionized. The Galactic halo is expected to have huge numbers of smaller neutral and ionized fragments. When the ionized component of the infalling gas is accounted for, the rate of gas accretion is

  17. North Greenland's Ice Shelves and Ocean Warming

    NASA Astrophysics Data System (ADS)

    Muenchow, A.; Schauer, U.; Padman, L.; Melling, H.; Fricker, H. A.

    2014-12-01

    Rapid disintegration of ice shelves (the floating extensions of marine-terminating glaciers) can lead to increasing ice discharge, thinning upstream ice sheets, rising sea level. Pine Island Glacier, Antarctica, and Jacobshavn Isbrae, Greenland, provide prominent examples of these processes which evolve at decadal time scales. We here focus on three glacier systems north of 78 N in Greenland, each of which discharges more than 10 Gt per year of ice and had an extensive ice shelf a decade ago; Petermann Gletscher (PG), Niogshalvfjerdsfjorden (79N), and Zachariae Isstrom (ZI). We summarize and discuss direct observations of ocean and glacier properties for these systems as they have evolved in the northwest (PG) and northeast (79N and ZI) of Greenland over the last two decades. We use a combination of modern and historical snapshots of ocean temperature and salinity (PG, 79N, ZI), moored observations in Nares Strait (PG), and snapshots of temperature and velocity fields on the broad continental shelf off northeast Greenland (79N, ZI) collected between 1993 and 2014. Ocean warming adjacent to PG has been small relative to the ocean warming adjacent to 79N and ZI; however, ZI lost its entire ice shelf during the last decade while 79N, less than 70 km to the north of ZI, remained stable. In contrast, PG has thinned by about 10 m/y just prior to shedding two ice islands representing almost half its ice shelf area or a fifth by volume. At PG advective ice flux divergence explains about half of the dominantly basal melting while response to non-steady external forcing explains the other half. The observations at PG,79N, and ZI suggest that remotely sensed ambient surface ocean temperatures are poor proxies to explain ice shelf thinning and retreat. We posit that local dynamics of the subsurface ocean heat flux matters most. Ocean heat must first be delivered over the sill into the fjord and then within the ice shelf cavity to the base of the shelf near the grounding line

  18. Warm Deuteration of Hydrogen Cyanide in Orion

    NASA Astrophysics Data System (ADS)

    Marcelino, N.; Tercero, B.; Cernicharo, J.; Roueff, E.; Palau, A.; Goicoechea, J. R.; Herschel HEXOS Team

    2011-05-01

    Deuterium fractionation has been observed both in cold molecular clouds and in star forming regions. In the latter it should be a remnant from the earlier cold prestellar phase where, after being frozen onto dust grains, deuterated species are released during the switch-on of the protostar. However this mechanism does not explain the large deuteration observed at moderately warm regions such as the Orion Bar and the molecular Ridge. Using HIFI data from the Guaranteed Time Key Program ``Herschel observations of EXtra-Ordinary Sources (HEXOS)'', we have detected high-J DCN transitions, up to J=17-16, toward Orion KL. On the other hand, DNC is not detected within the HIFI frequency range. Furthermore, the DCN J=2-1, 2x2' maps observed with the IRAM 30m telescope show extended emission along the molecular filament revealing the moderate and warm conditions under DCN seems to be produced (Extended and Compact Ridge, Hot Core and Orion-S). On the other hand, DNC J=2--1 emission is much less extended and it does not show an emission peak at the KL position, like DCN, but toward an offset (-20'',-25'') from IRc2. In our analysis we have combined the HIFI data with that of the Orion surveys performed at the 30m, thus including a wide range of excitation conditions. In order to reproduce the observed profiles and compute column densities, we have used the LVG approximation and a source model with a three layer stratification for the Compact Ridge, Plateau and Hot Core components. The abundance ratio DCN/HCN is found to be an order of magnitude higher than the DNC/HNC one for the Compact Ridge and the Hot Core components (Tkin=100-300 K) while the opposite behaviour is obtained for the Extended Ridge (Tkin=60 K), suggesting different deuteration pathways for these two isomers. This study demonstrates that observations covering a wide range of excitation conditions are mandatory to better constrain the physical properties in such a complex region as Orion. This was possible

  19. Warm Jupiters from Secular Planet-Planet Interactions

    NASA Astrophysics Data System (ADS)

    Petrovich, Cristobal; Tremaine, Scott

    2016-10-01

    Most warm Jupiters (gas-giant planets with 0.1 {{au}}≲ a≲ 1 au) have pericenter distances that are too large for significant orbital migration by tidal friction. We study the possibility that the warm Jupiters are undergoing secular eccentricity oscillations excited by an outer companion (a planet or star) in an eccentric and/or mutually inclined orbit. In this model, the warm Jupiters migrate periodically, in the high-eccentricity phase of the oscillation, but are typically observed at lower eccentricities. We show that in this model the steady-state eccentricity distribution of the warm Jupiters is approximately flat, which is consistent with the observed distribution if we restrict the sample to warm Jupiters with detected outer planetary companions. The eccentricity distribution of warm Jupiters without companions exhibits a peak at e≲ 0.2 that must be explained by a different formation mechanism. Based on a population synthesis study, we find that high-eccentricity migration excited by an outer planetary companion (1) can account for ˜ 20 % of the warm Jupiters and most of the warm Jupiters with e≳ 0.4; and (2) can produce most of the observed population of hot Jupiters, with a semimajor axis distribution that matches the observations, but fails to account adequately for ˜ 60 % of hot Jupiters with projected obliquities ≲ 20^\\circ . Thus ˜ 20 % of the warm Jupiters and ˜ 60 % of the hot Jupiters can be produced by high-eccentricity migration. We also provide predictions for the expected mutual inclinations and spin-orbit angles of the planetary systems with hot and warm Jupiters produced by high-eccentricity migration.

  20. 75 FR 57976 - Designation of Service Area for Confederated Tribes of the Warm Springs of Oregon

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-23

    ... Bureau of Indian Affairs Designation of Service Area for Confederated Tribes of the Warm Springs of... Tribes of Warm Springs of Oregon, Warm Springs, Oregon (Warm Springs Tribe) for financial assistance and...: The Warm Springs Tribe submitted to BIA a request with supporting documentation to modify its...

  1. Halocarbon ozone depletion and global warming potentials

    NASA Technical Reports Server (NTRS)

    Cox, Richard A.; Wuebbles, D.; Atkinson, R.; Connell, Peter S.; Dorn, H. P.; Derudder, A.; Derwent, Richard G.; Fehsenfeld, F. C.; Fisher, D.; Isaksen, Ivar S. A.

    1990-01-01

    Concern over the global environmental consequences of fully halogenated chlorofluorocarbons (CFCs) has created a need to determine the potential impacts of other halogenated organic compounds on stratospheric ozone and climate. The CFCs, which do not contain an H atom, are not oxidized or photolyzed in the troposphere. These compounds are transported into the stratosphere where they decompose and can lead to chlorine catalyzed ozone depletion. The hydrochlorofluorocarbons (HCFCs or HFCs), in particular those proposed as substitutes for CFCs, contain at least one hydrogen atom in the molecule, which confers on these compounds a much greater sensitivity toward oxidation by hydroxyl radicals in the troposphere, resulting in much shorter atmospheric lifetimes than CFCs, and consequently lower potential for depleting ozone. The available information is reviewed which relates to the lifetime of these compounds (HCFCs and HFCs) in the troposphere, and up-to-date assessments are reported of the potential relative effects of CFCs, HCFCs, HFCs, and halons on stratospheric ozone and global climate (through 'greenhouse' global warming).

  2. Global Warming and the Microwave Background.

    NASA Astrophysics Data System (ADS)

    Robitaille, Pierre-Marie

    2008-10-01

    The energy balance of our planet is determined by the relationship between absorbed (solar) and emitted (earthly) radiation. In many models, the Earth's radiation is derived by applying Stefan's Law, at a given effective temperature, thereby treating the globe as a uniform blackbody source. However, the oceans cannot be treated as simple blackbody emitters. In fact, while water can provide strong emission bands in the IR, the spectrum is far from blackbody. This is particularly important in the microwave region where the oceans mimic a 3K blackbody source (the Penzias and Wilson signal). As a result, the oceans are poor emitters of radiation in this spectral range. Their inability to efficiently emit radiation results in substantial retention of thermal energy within oceanic systems. Unable to dissipate heat through emission, the oceans turn to convection currents. This provides a driving force for oceanic currents and for hurricanes. It is in the interest of the United States to properly ascertain the Earth's emission profile by using an array of satellites which continually monitor spectral emissions from the microwave through the IR. These satellites will reveal that the Penzias and Wilson signal does originate from the oceans. It is only when the complete emission profile of the Earth is properly understood that mankind will begin to make real progress in modeling global warming.

  3. Is obesity associated with global warming?

    PubMed

    Squalli, J

    2014-12-01

    Obesity is a national epidemic that imposes direct medical and indirect economic costs on society. Recent scholarly inquiries contend that obesity also contributes to global warming. The paper investigates the relationship between greenhouse gas emissions and obesity. Cross-sectional state-level data for the year 2010. Multiple regression analysis using least squares with bootstrapped standard errors and quantile regression. States with higher rates of obesity are associated with higher CO2 and CH4 emissions (p < 0.05) and marginally associated with higher N2O emissions (p < 0.10), net of other factors. Reverting to the obesity rates of the year 2000 across the entire United States could decrease greenhouse gas emissions by about two percent, representing more than 136 million metric tons of CO2 equivalent. Future studies should establish clear causality between obesity and emissions by using longitudinal data while controlling for other relevant factors. They should also consider identifying means to net out the potential effects of carbon sinks, conversion of CH4 to energy, cross-state diversion, disposal, and transfer of municipal solid waste, and potentially lower energy consumption from increased sedentariness. Copyright © 2014 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  4. Title: Freshwater phytoplankton responses to global warming.

    PubMed

    Wagner, Heiko; Fanesi, Andrea; Wilhelm, Christian

    2016-09-20

    Global warming alters species composition and function of freshwater ecosystems. However, the impact of temperature on primary productivity is not sufficiently understood and water quality models need to be improved in order to assess the quantitative and qualitative changes of aquatic communities. On the basis of experimental data, we demonstrate that the commonly used photosynthetic and water chemistry parameters alone are not sufficient for modeling phytoplankton growth under changing temperature regimes. We present some new aspects of the acclimation process with respect to temperature and how contrasting responses may be explained by a more complete physiological knowledge of the energy flow from photons to new biomass. We further suggest including additional bio-markers/traits for algal growth such as carbon allocation patterns to increase the explanatory power of such models. Although carbon allocation patterns are promising and functional cellular traits for growth prediction under different nutrient and light conditions, their predictive power still waits to be tested with respect to temperature. A great challenge for the near future will be the prediction of primary production efficiencies under the global change scenario using a uniform model for phytoplankton assemblages. Copyright © 2016 Elsevier GmbH. All rights reserved.

  5. Responses of Antarctic Oscillation to global warming

    NASA Astrophysics Data System (ADS)

    Feng, S.

    2015-12-01

    The Antarctic Oscillation (AAO) is the major annular mode dominates the spatiotemporal variability of the atmospheric circulation in the Southern Hemisphere. This study examined the sensitivity of AAO to future warming by analyzing the outputs of 34 state-of-the-art climate models participating in phase 5 of the Coupled Model Intercomparion Project (CMIP5). The model simulations include the stabilized (RCP4.5) and business as usual (RCP8.5) scenarios as well as the idealized 1% per year increase in atmospheric CO2 to quadrupling (1pctCO2) and an instantaneous quadrupling of CO2 (abrupt4xCO2). We show that the CMIP5 models on average simulate increases in the AAO in every season by 2100 under the RCP4.5 and RCP8.5 scenarios. However, due to the impacts of ozone, aerosol and land use changes, the amplitudes of the projected changes in AAO to future climate scenarios are quit different on different seasons. After the impact of ozone, aerosol and land use changes were removed; it was found that the impact of greenhouse gases (GHGs) on AAO is similar on all seasons. The increases of AAO are accelerating following the increase of GHGs. Our results are also consistent with the simulations of 1pctCO2 and abrupt4xCO2.

  6. Talking about Climate Change and Global Warming

    PubMed Central

    Kim, Ji Yoon; Joo, Gea-Jae

    2015-01-01

    The increasing prevalence of social networks provides researchers greater opportunities to evaluate and assess changes in public opinion and public sentiment towards issues of social consequence. Using trend and sentiment analysis is one method whereby researchers can identify changes in public perception that can be used to enhance the development of a social consciousness towards a specific public interest. The following study assessed Relative search volume (RSV) patterns for global warming (GW) and Climate change (CC) to determine public knowledge and awareness of these terms. In conjunction with this, the researchers looked at the sentiment connected to these terms in social media networks. It was found that there was a relationship between the awareness of the information and the amount of publicity generated around the terminology. Furthermore, the primary driver for the increase in awareness was an increase in publicity in either a positive or a negative light. Sentiment analysis further confirmed that the primary emotive connections to the words were derived from the original context in which the word was framed. Thus having awareness or knowledge of a topic is strongly related to its public exposure in the media, and the emotional context of this relationship is dependent on the context in which the relationship was originally established. This has value in fields like conservation, law enforcement, or other fields where the practice can and often does have two very strong emotive responses based on the context of the problems being examined. PMID:26418127

  7. Microbial diseases of corals and global warming.

    PubMed

    Rosenberg, Eugene; Ben-Haim, Yael

    2002-06-01

    Coral bleaching and other diseases of corals have increased dramatically during the last few decades. As outbreaks of these diseases are highly correlated with increased sea-water temperature, one of the consequences of global warming will probably be mass destruction of coral reefs. The causative agent(s) of a few of these diseases have been reported: bleaching of Oculina patagonica by Vibrio shiloi; black band disease by a microbial consortium; sea-fan disease (aspergillosis) by Aspergillus sydowii; and coral white plague possibly by Sphingomonas sp. In addition, we have recently discovered that Vibrio coralyticus is the aetiological agent for bleaching the coral Pocillopora damicornis in the Red Sea. In the case of coral bleaching by V. shiloi, the major effect of increasing temperature is the expression of virulence genes by the pathogen. At high summer sea-water temperatures, V. shiloi produces an adhesin that allows it to adhere to a beta-galactoside-containing receptor in the coral mucus, penetrate into the coral epidermis, multiply intracellularly, differentiate into a viable-but-not-culturable (VBNC) state and produce toxins that inhibit photosynthesis and lyse the symbiotic zooxanthellae. In black band disease, sulphide is produced at the coral-microbial biofilm interface, which is probably responsible for tissue death. Reports of newly emerging coral diseases and the lack of epidemiological and biochemical information on the known diseases indicate that this will become a fertile area of research in the interface between microbial ecology and infectious disease.

  8. Talking about Climate Change and Global Warming.

    PubMed

    Lineman, Maurice; Do, Yuno; Kim, Ji Yoon; Joo, Gea-Jae

    2015-01-01

    The increasing prevalence of social networks provides researchers greater opportunities to evaluate and assess changes in public opinion and public sentiment towards issues of social consequence. Using trend and sentiment analysis is one method whereby researchers can identify changes in public perception that can be used to enhance the development of a social consciousness towards a specific public interest. The following study assessed Relative search volume (RSV) patterns for global warming (GW) and Climate change (CC) to determine public knowledge and awareness of these terms. In conjunction with this, the researchers looked at the sentiment connected to these terms in social media networks. It was found that there was a relationship between the awareness of the information and the amount of publicity generated around the terminology. Furthermore, the primary driver for the increase in awareness was an increase in publicity in either a positive or a negative light. Sentiment analysis further confirmed that the primary emotive connections to the words were derived from the original context in which the word was framed. Thus having awareness or knowledge of a topic is strongly related to its public exposure in the media, and the emotional context of this relationship is dependent on the context in which the relationship was originally established. This has value in fields like conservation, law enforcement, or other fields where the practice can and often does have two very strong emotive responses based on the context of the problems being examined.

  9. Global Warming: The Threat to the Planet

    NASA Astrophysics Data System (ADS)

    Hansen, James

    2007-04-01

    Paleoclimate data show that the Earth's climate is remarkably sensitive to global forcings. Positive feedbacks predominate. This allows the entire planet to be whipsawed between climate states. One feedback, the `albedo flip' property of water substance, provides a powerful trigger mechanism. A climate forcing that `flips' the albedo of a sufficient portion of an ice sheet can spark a cataclysm. Ice sheet and ocean inertia provides only moderate delay to ice sheet disintegration and a burst of added global warming. Recent greenhouse gas (GHG) emissions place the Earth perilously close to dramatic climate change that could run out of our control, with great dangers for humans and other creatures. CO2 is the largest human-made climate forcing, but CH4, O3, N2O and black carbon (BC) are important. Only intense simultaneous efforts to slow CO2 emissions and reduce non-CO2 forcings can keep climate within or near the range of the past million years. Some forcings are especially effective at high latitudes, so concerted efforts to reduce their emissions could still ``save the Arctic,'' while also having major benefits for human health, agricultural productivity, and the global environment.

  10. Detecting the warm-hot intergalactic medium

    NASA Astrophysics Data System (ADS)

    den Herder, Jan-Willem; Paerels, Frits B. S.; Rasmussen, Andrew; Bruijn, Marcel; Hoevers, Henk; Kaastra, Jelle S.; Kahn, Steven M.; de Korte, Piet A.; Scharf, Caleb

    2004-10-01

    A very significant fraction of the baryonic matter in the local universe is predicted to form a Warm Hot Intergalactic Medium (WHIM) of very low density, moderately hot gas, tracing the cosmic web. Its X-ray emission is dominated by metal features, but is weak (< 0.01 photons/cm2/s/sr) and potentially hard to separate from the galactic component. However, a mission capable of directly mapping this component of the large scale structure of the universe, via a small number of well chosen emission lines, is now within reach due to recent improvements in cryogenic X-ray detector energy resolution. To map the WHIM, the energy resolution and grasp are optimized. A number of missions have been proposed to map the missing baryons including MBE (US/SMEX program) and DIOS (Japan). The design of the mirror and detector have still room for improvements which will be discussed. With these improvements it is feasible to map a 10 x 10 degree area of the sky in 2 years out to z = 0.2 with sufficient sensitivity to directly detect WHIM structure, such as filaments connecting clusters of galaxies. This structure is predicted by the current Cold Dark Matter paradigm which thus far appears to provide a good description of the distribution of matter as traced by galaxies.

  11. Ion Acoustic Modes in Warm Dense Matter

    NASA Astrophysics Data System (ADS)

    Hartley, Nicholas; Monaco, Guilio; White, Thomas; Gregori, Gianluca; Graham, Peter; Fletcher, Luke; Appel, Karen; Tschentscher, Thomas; Lee, Hae Ja; Nagler, Bob; Galtier, Eric; Granados, Eduardo; Heimann, Philip; Zastrau, Ulf; Doeppner, Tilo; Gericke, Dirk; Lepape, Sebastien; Ma, Tammy; Pak, Art; Schropp, Andreas; Glenzer, Siegfried; Hastings, Jerry

    2015-06-01

    We present results that, for the first time, show scattering from ion acoustic modes in warm dense matter, representing an unprecedented level of energy resolution in the study of dense plasmas. The experiment was carried out at the LCLS facility in California on an aluminum sample at 7 g/cc and 5 eV. Using an X-ray probe at 8 keV, shifted peaks at +/-150 meV were observed. Although the energy shifts from interactions with the acoustic waves agree with predicted values from DFT-MD models, a central (elastic) peak was also observed, which did not appear in modelled spectra and may be due to the finite timescale of the simulation. Data fitting with a hydrodynamic form has proved able to match the observed spectrum, and provide measurements of some thermodynamic properties of the system, which mostly agree with predicted values. Suggest for further experiments to determine the cause of the disparity are also given.

  12. Ion Beam Driven Warm Dense Matter Experiments

    NASA Astrophysics Data System (ADS)

    Bieniosek, F. M.; Henestroza, E.; Leitner, M. A.; Lidia, S. M.; Logan, B. G.; More, R. M.; Ni, P. A.; Seidl, P. A.; Waldron, W. L.; Barnard, J. J.

    2008-11-01

    We report plans and experimental results in ion beam-driven warm dense matter (WDM) experiments. Initial experiments use a 0.3 MeV K+ beam from the NDCX-I accelerator. The WDM conditions are to be achieved by longitudinal and transverse neutralized drift compression to provide a hot spot on the target with a 1-mm beam spot size, and 2-ns pulse length. As a technique for heating matter to high energy density, intense ion beams can deliver precise and uniform beam energy deposition, in a relatively large sample size, and can heat any solid-phase target material. The range of the beams in solid targets is less than 1 micron, which can be lengthened by using reduced density porous targets. We have developed a WDM target chamber and target diagnostics including a fast multi-channel optical pyrometer, optical streak camera, VISAR, and high-speed gated cameras. Initial experiments will explore measurement of temperature and other target parameters. Experiments are planned in areas such as dense electronegative targets, porous target homogenization and two-phase equation of state.

  13. Transient reducing greenhouse warming on early Mars

    NASA Astrophysics Data System (ADS)

    Wordsworth, R.; Kalugina, Y.; Lokshtanov, S.; Vigasin, A.; Ehlmann, B.; Head, J.; Sanders, C.; Wang, H.

    2017-01-01

    The evidence for abundant liquid water on early Mars despite the faint young Sun is a long-standing problem in planetary research. Here we present new ab initio spectroscopic and line-by-line climate calculations of the warming potential of reduced atmospheres on early Mars. We show that the strength of both CO2-H2 and CO2-CH4 collision-induced absorption (CIA) has previously been significantly underestimated. Contrary to previous expectations, methane could have acted as a powerful greenhouse gas on early Mars due to CO2-CH4 CIA in the critical 250-500 cm-1 spectral window region. In atmospheres of 0.5 bar CO2 or more, percent levels of H2 or CH4 raise annual mean surface temperatures by tens of degrees, with temperatures reaching 273 K for pressures of 1.25-2 bars and 2-10% of H2 and CH4. Methane and hydrogen produced following aqueous alteration of Mars' crust could have combined with volcanically outgassed CO2 to form transient atmospheres of this composition 4.5-3.5 Ga. Our results also suggest that inhabited exoplanets could retain surface liquid water at significant distances from their host stars.

  14. Potential effects on health of global warming

    SciTech Connect

    Haines, A. . Whittington Hospital); Parry, M. . Environmental Change Unit)

    1993-12-01

    Prediction of the impacts of global climate change on health is complicated by a number of factors. These include: the difficulty in predicting regional changes in climate, the capacity for adaptation to climate change, the interactions between the effects of global climate change and a number of other key determinants of health, including population growth and poverty, and the availability of adequate preventive and curative facilities for diseases that may be effected by climate change. Nevertheless, it is of importance to consider the potential health impacts of global climate change for a number of reasons. It is also important to monitor diseases which could be effected by climate change in order to detect changes in incidence as early as possible and study possible interactions with other factors. It seems likely that the possible impacts on health of climate change will be a major determinant of the degree to which policies aimed at reducing global warming are followed, as perceptions of the effect of climate change to human health and well-being are particularly likely to influence public opinion. The potential health impacts of climate change can be divided into direct (primary) and indirect (secondary and tertiary) effects. Primary effects are those related to the effect of temperature on human well-being and disease. Secondary effects include the impacts on health of changes in food production, availability of water and of sea level rise. A tertiary level of impacts can also be hypothesized.

  15. Mach reflection in a warm dense plasma

    NASA Astrophysics Data System (ADS)

    Foster, J. M.; Rosen, P. A.; Wilde, B. H.; Hartigan, P.; Perry, T. S.

    2010-11-01

    The phenomenon of irregular shock-wave reflection is of importance in high-temperature gas dynamics, astrophysics, inertial-confinement fusion, and related fields of high-energy-density science. However, most experimental studies of irregular reflection have used supersonic wind tunnels or shock tubes, and few or no data are available for Mach reflection phenomena in the plasma regime. Similarly, analytic studies have often been confined to calorically perfect gases. We report the first direct observation, and numerical modeling, of Mach stem formation for a warm, dense plasma. Two ablatively driven aluminum disks launch oppositely directed, near-spherical shock waves into a cylindrical plastic block. The interaction of these shocks results in the formation of a Mach-ring shock that is diagnosed by x-ray backlighting. The data are modeled using radiation hydrocodes developed by AWE and LANL. The experiments were carried out at the University of Rochester's Omega laser [J. M. Soures, R. L. McCrory, C. P. Verdon et al., Phys. Plasmas 3, 2108 (1996)] and were inspired by modeling [A. M. Khokhlov, P. A. Höflich, E. S. Oran et al., Astrophys J. 524, L107 (1999)] of core-collapse supernovae that suggest that in asymmetric supernova explosion significant mass may be ejected in a Mach-ring formation launched by bipolar jets.

  16. The Tropical Warm Pool International Cloud Experiment

    SciTech Connect

    May, Peter T.; Mather, James H.; Vaughan, Geraint; Jakob, Christian; McFarquhar, Greg; Bower, Keith; Mace, Gerald G.

    2008-05-01

    One of the most complete data sets describing tropical convection ever collected will result from the upcoming Tropical Warm Pool International Cloud Experiment (TWP-ICE) in the area around Darwin, Northern Australia in January and February 2006. The aims of the experiment, which will be operated in conjunction with the DOE Atmospheric Radiation Measurement (ARM) site in Darwin, will be to examine convective cloud systems from their initial stages through to the decay of the cirrus generated and to measure their impact on the environment. The experiment will include an unprecedented network of ground-based observations (soundings, active and passive remote sensors) combined with low, mid and high altitude aircraft for in-situ and remote sensing measurements. A crucial outcome of the experiment will be a data set suitable to provide the forcing and evaluation data required by cloud resolving and single column models as well as global climate models (GCMs) with the aim to contribute to parameterization development. This data set will provide the necessary link between the observed cloud properties and the models that are attempting to simulate them. The experiment is a large multi-agency experiment including substantial contributions from the United States DOE ARM program, ARM-UAV program, NASA, the Australian Bureau of Meteorology, CSIRO, EU programs and many universities.

  17. Sterile neutrinos as subdominant warm dark matter

    SciTech Connect

    Palazzo, A.; Cumberbatch, D.; Slosar, A.; Silk, J.

    2007-11-15

    In light of recent findings which seem to disfavor a scenario with (warm) dark matter entirely constituted of sterile neutrinos produced via the Dodelson-Widrow mechanism, we investigate the constraints attainable for this mechanism by relaxing the usual hypothesis that the relic neutrino abundance must necessarily account for all of the dark matter. We first study how to reinterpret the limits attainable from x-ray nondetection and Lyman-{alpha} forest measurements in the case that sterile neutrinos constitute only a fraction f{sub s} of the total amount of dark matter. Then, assuming that sterile neutrinos are generated in the early universe solely through the Dodelson-Widrow mechanism, we show how the x-ray and Lyman-{alpha} results jointly constrain the mass-mixing parameters governing their production. Furthermore, we show how the same data allow us to set a robust upper limit f{sub s} < or approx. 0.7 at the 2{sigma} level, rejecting the case of dominant dark matter (f{sub s}=1) at the {approx}3{sigma} level.

  18. REIONIZATION IN THE WARM DARK MATTER MODEL

    SciTech Connect

    Yue Bin; Chen Xuelei

    2012-03-10

    Compared with the cold dark matter (CDM) model, the formation of the small-scale structure of the universe is suppressed in the warm dark matter (WDM) model. It is often thought that this would delay the reionization of the intergalactic medium (IGM) because the star formation rate during the epoch of reionization (EOR) would be lowered. However, during the later stage of the EOR, a large portion of the ionizing photons is consumed by recombination inside the minihalos, which is where the gas has higher density and recombination rates than that in the IGM. The suppression of the small-scale structure would therefore reduce the recombination rate and could potentially shorten the reionization process. This effect is investigated here by using the analytical 'bubble model' of reionization. We find that, in some cases, although the initiation of the EOR is delayed in the WDM model, its completion could be even earlier than the CDM case, but the effect is generally small. We obtain limits on the mass of WDM particles for different reionization redshifts.

  19. Tropospheric circulation during the early twentieth century Arctic warming

    NASA Astrophysics Data System (ADS)

    Wegmann, Martin; Brönnimann, Stefan; Compo, Gilbert P.

    2017-04-01

    The early twentieth century Arctic warming (ETCAW) between 1920 and 1940 is an exceptional feature of climate variability in the last century. Its warming rate was only recently matched by recent warming in the region. Unlike recent warming largely attributable to anthropogenic radiative forcing, atmospheric warming during the ETCAW was strongest in the mid-troposphere and is believed to be triggered by an exceptional case of natural climate variability. Nevertheless, ultimate mechanisms and causes for the ETCAW are still under discussion. Here we use state of the art multi-member global circulation models, reanalysis and reconstruction datasets to investigate the internal atmospheric dynamics of the ETCAW. We investigate the role of boreal winter mid-tropospheric heat transport and circulation in providing the energy for the large scale warming. Analyzing sensible heat flux components and regional differences, climate models are not able to reproduce the heat flux evolution found in reanalysis and reconstruction datasets. These datasets show an increase of stationary eddy heat flux and a decrease of transient eddy heat flux during the ETCAW. Moreover, tropospheric circulation analysis reveals the important role of both the Atlantic and the Pacific sectors in the convergence of southerly air masses into the Arctic during the warming event. Subsequently, it is suggested that the internal dynamics of the atmosphere played a major role in the formation in the ETCAW.

  20. Continental warming preceding the Palaeocene-Eocene thermal maximum.

    PubMed

    Secord, Ross; Gingerich, Philip D; Lohmann, Kyger C; Macleod, Kenneth G

    2010-10-21

    Marine and continental records show an abrupt negative shift in carbon isotope values at ∼55.8 Myr ago. This carbon isotope excursion (CIE) is consistent with the release of a massive amount of isotopically light carbon into the atmosphere and was associated with a dramatic rise in global temperatures termed the Palaeocene-Eocene thermal maximum (PETM). Greenhouse gases released during the CIE, probably including methane, have often been considered the main cause of PETM warming. However, some evidence from the marine record suggests that warming directly preceded the CIE, raising the possibility that the CIE and PETM may have been linked to earlier warming with different origins. Yet pre-CIE warming is still uncertain. Disentangling the sequence of events before and during the CIE and PETM is important for understanding the causes of, and Earth system responses to, abrupt climate change. Here we show that continental warming of about 5 °C preceded the CIE in the Bighorn Basin, Wyoming. Our evidence, based on oxygen isotopes in mammal teeth (which reflect temperature-sensitive fractionation processes) and other proxies, reveals a marked temperature increase directly below the CIE, and again in the CIE. Pre-CIE warming is also supported by a negative amplification of δ(13)C values in soil carbonates below the CIE. Our results suggest that at least two sources of warming-the earlier of which is unlikely to have been methane-contributed to the PETM.

  1. Small inner companions of warm Jupiters: Lifetimes and legacies

    SciTech Connect

    Van Laerhoven, Christa; Greenberg, Richard

    2013-12-01

    Although warm Jupiters are generally too far from their stars for tides to be important, the presence of an inner planetary companion to a warm Jupiter can result in tidal evolution of the system. Insight into the process and its effects comes form classical secular theory of planetary perturbations. The lifetime of the inner planet may be shorter than the age of the system, because the warm Jupiter maintains its eccentricity and hence promotes tidal migration into the star. Thus a warm Jupiter observed to be alone in its system might have previously cleared away any interior planets. Before its demise, even if an inner planet is of terrestrial scale, it may promote damping of the warm Jupiter's eccentricity. Thus any inferences of the initial orbit of an observed warm Jupiter must include the possibility of a greater initial eccentricity than would be estimated by assuming it had always been alone. Tidal evolution involving multiple planets also enhances the internal heating of the planets, which readily exceeds that of stellar radiation for the inner planet, and may be great enough to affect the internal structure of warm Jupiters. Secular theory gives insight into the tidal processes, providing, among other things, a way to constrain eccentricities of transiting planets based on estimates of the tidal parameter Q.

  2. Experimental warming effects on the bacterial community structure and diversity

    NASA Astrophysics Data System (ADS)

    Kim, W.; Han, S.; Adams, J.; Son, Y.

    2014-12-01

    The objective of this study is to investigate the responses of soil bacterial community to future temperature increase by conducting open-field warming experiment. We conducted an open-field experimental warming system using infra-red heater in 2011 and regulated the temperature of warmed plots by 3oC higher than that of control plots constantly. The seeds of Pinus densiflora, Abies holophylla, Abies koreana, Betula costata, Quercus variabilis, Fraxinus rhynchophylla, and Zelkova serrata were planted in each 1 m × 1 m plot (n=3) in April, 2012. We collected soil samples from the rhizosphere of 7 tree species. DNA was extracted and PCR-amplified for the bacterial 16S gene targeting V1-V3 region. The paired-end sequencing was performed at Beijing Genome Institute (BGI, Hong Kong, China) using 2× 100 bp Hiseq2000 (Illumina). This study aimed to answer the following prediction/hypothesis: 1) Experimental warming will change the structure of soil bacterial community, 2) There will be distinct 'indicator group' which response to warming treatment relatively more sensitive than other groups. 3) Warming treatment will enhance the microbial activity in terms of soil respiration. 4) The rhizoplane bacterial communities for each of 7 tree species will show different response pattern to warming treatment. Since the sequence data does not arrive before the submission deadline, therefore, we would like to present the results and discussions on December 2014, AGU Fall Meeting.

  3. Glacial terminations as southern warmings without northern control

    NASA Astrophysics Data System (ADS)

    Wolff, E. W.; Fischer, H.; Röthlisberger, R.

    2009-03-01

    The change from a glacial to an interglacial climate is paced by variations in Earth's orbit. However, the detailed sequence of events that leads to a glacial termination remains controversial. It is particularly unclear whether the northern or southern hemisphere leads the termination. Here we present a hypothesis for the beginning and continuation of glacial terminations, which relies on the observation that the initial stages of terminations are indistinguishable from the warming stage of events in Antarctica known as Antarctic Isotopic Maxima, which occur frequently during glacial periods. Such warmings in Antarctica generally begin to reverse with the onset of a warm Dansgaard-Oeschger event in the northern hemisphere. However, in the early stages of a termination, Antarctic warming is not followed by any abrupt warming in the north. We propose that the lack of an Antarctic climate reversal enables southern warming and the associated atmospheric carbon dioxide rise to reach a point at which full deglaciation becomes inevitable. In our view, glacial terminations, in common with other warmings that do not lead to termination, are led from the southern hemisphere, but only specific conditions in the northern hemisphere enable the climate state to complete its shift to interglacial conditions.

  4. A policy synthesis approach for slowing global warming

    SciTech Connect

    Timilsina, G.R.

    1996-12-31

    Global warming is a burning environmental issue today but confronting with subjective as well as policy conflicts. The findings of various studies indicate that developed countries that are capable of affording effective measures towards the global warming mitigation have fewer incentives for doing so because they will have a minimal damage from global warming. The developing countries, although they will have greater damage, are unlikely to divert their development budget for taking preventive actions towards global warming. The only solution in this situation is to design a policy that encourages all the nation in the world to participate in the programs for slowing global warming. Without active participation of all nations, it seems unlikely to reduce the global warming problem in an effective way. This study presents a qualitative policy recommendation extracted from a comprehensive analysis of the findings of several studies conducted so far in this field. This study has categorized the policy approaches for mitigating the global warming in three groups: Engineering approach, forestry approach and economic approach.

  5. Laparoscopic partial nephrectomy: effect of warm ischemia on serum creatinine.

    PubMed

    Bhayani, Sam B; Rha, Koon H; Pinto, Peter A; Ong, Albert M; Allaf, Mohamad E; Trock, Bruce J; Jarrett, Thomas W; Kavoussi, Louis R

    2004-10-01

    Laparoscopic partial nephrectomy (LPN) has been shown to be a safe and effective option for small renal tumors. However, limited data are available regarding the effect of warm ischemic time on postoperative renal function. We assessed the effect of variable durations of warm ischemia on long-term renal function in patients undergoing LPN. A total of 118 patients with a single, unilateral, sporadic renal tumor and normal contralateral kidney underwent LPN from August 1998 to November 2002. Patients were divided into 3 groups based on warm ischemic time, namely group 1-no renal occlusion in 42, group 2-warm ischemia less than 30 minutes in 48 and group 3-warm ischemia greater than 30 minutes in 28. All 3 groups were assessed for changes in serum creatinine 6 months after LPN. Additionally, renal remnants were examined with cross-sectional imaging. At a median followup of 28 months (range 6 to 56) median creatinine had not statistically increased postoperatively. None of the 118 patients progressed to renal insufficiency or required dialysis after LPN. Based on postoperative serum creatinine warm ischemia time up to 55 minutes does not significantly influence long-term renal function after LPN. Thus, during LPN efforts to minimize warm ischemia are important but they should not jeopardize cancer control, hemostasis or collecting system closure.

  6. Global warming /climate change: Involving students using local example.

    NASA Astrophysics Data System (ADS)

    Isiorho, S. A.

    2016-12-01

    The current political climate has made it apparent that the general public does not believe in global warming. Also, there appears to be some confusion between global warming and climate change; global warming is one aspect of climate change. Most scientists believe there is climate change and global warming, although, there is still doubt among students on global warming. Some upper level undergraduate students are required to conduct water level/temperature measurements as part of their course grade. In addition to students having their individual projects, the various classes also utilize a well field within a wetland on campus to conduct group projects. Twelve wells in the well field on campus are used regularly by students to measure the depth of groundwater, the temperature of the waters and other basic water chemistry parameters like pH, conductivity and total dissolved solid (TDS) as part of the class group project. The data collected by each class is added to data from previous classes. Students work together as a group to interpret the data. More than 100 students have participated in this venture for more than 10 years of the four upper level courses: hydrogeology, environmental and urban geology, environmental conservation and wetlands. The temperature trend shows the seasonal variation as one would expect, but it also shows an upward trend (warming). These data demonstrate a change in climate and warming. Thus, the students participated in data collection, learn to write report and present their result to their peers in the classrooms.

  7. Does the climate warming hiatus exist over the Tibetan Plateau?

    PubMed Central

    Duan, Anmin; Xiao, Zhixiang

    2015-01-01

    The surface air temperature change over the Tibetan Plateau is determined based on historical observations from 1980 to 2013. In contrast to the cooling trend in the rest of China, and the global warming hiatus post-1990s, an accelerated warming trend has appeared over the Tibetan Plateau during 1998–2013 (0.25 °C decade−1), compared with that during 1980–1997 (0.21 °C decade−1). Further results indicate that, to some degree, such an accelerated warming trend might be attributable to cloud–radiation feedback. The increased nocturnal cloud over the northern Tibetan Plateau would warm the nighttime temperature via enhanced atmospheric back-radiation, while the decreased daytime cloud over the southern Tibetan Plateau would induce the daytime sunshine duration to increase, resulting in surface air temperature warming. Meanwhile, the in situ surface wind speed has recovered gradually since 1998, and thus the energy concentration cannot explain the accelerated warming trend over the Tibetan Plateau after the 1990s. It is suggested that cloud–radiation feedback may play an important role in modulating the recent accelerated warming trend over the Tibetan Plateau. PMID:26329678

  8. Value of extended warming in patients undergoing elective surgery.

    PubMed

    Wasfie, Tarik J; Barber, Kimberly R

    2015-01-01

    Perioperative temperature management is imperative for positive surgical outcomes. This study assessed the clinical and wellbeing benefits of extending normothermia by using a portable warming gown. A total of 94 patients undergoing elective surgery were enrolled. They were randomized pre-operatively to either a portable warming gown or the standard warming procedure. The warming gown stayed with patients from pre-op to operating room to postrecovery room discharge. Core temperature was tracked throughout the study. Patients also provided responses to a satisfaction and comfort status survey. The change in average core temperature did not differ significantly between groups (P = 0.23). A nonsignificant 48% relative decrease in hypothermic events was observed for the extended warming group (P = 0.12). Patients receiving the warming gown were more likely to report always having their temperature controlled (P = 0.04) and significantly less likely to request additional blankets for comfort (P = 0.006). Clinical outcomes and satisfaction were improved for patients with extended warming.

  9. Tropospheric circulation during the early twentieth century Arctic warming

    NASA Astrophysics Data System (ADS)

    Wegmann, Martin; Brönnimann, Stefan; Compo, Gilbert P.

    2016-06-01

    The early twentieth century Arctic warming (ETCAW) between 1920 and 1940 is an exceptional feature of climate variability in the last century. Its warming rate was only recently matched by recent warming in the region. Unlike recent warming largely attributable to anthropogenic radiative forcing, atmospheric warming during the ETCAW was strongest in the mid-troposphere and is believed to be triggered by an exceptional case of natural climate variability. Nevertheless, ultimate mechanisms and causes for the ETCAW are still under discussion. Here we use state of the art multi-member global circulation models, reanalysis and reconstruction datasets to investigate the internal atmospheric dynamics of the ETCAW. We investigate the role of boreal winter mid-tropospheric heat transport and circulation in providing the energy for the large scale warming. Analyzing sensible heat flux components and regional differences, climate models are not able to reproduce the heat flux evolution found in reanalysis and reconstruction datasets. These datasets show an increase of stationary eddy heat flux and a decrease of transient eddy heat flux during the ETCAW. Moreover, tropospheric circulation analysis reveals the important role of both the Atlantic and the Pacific sectors in the convergence of southerly air masses into the Arctic during the warming event. Subsequently, it is suggested that the internal dynamics of the atmosphere played a major role in the formation in the ETCAW.

  10. Singer and listener perception of vocal warm-up.

    PubMed

    Moorcroft, Lynda; Kenny, Dianna T

    2013-03-01

    This study investigated changes perceived by singers and listeners after the singers had vocally warmed up. The study used a repeated measures within-subject design to assess changes in vibrato quality from pre (nonwarmed-up voice) to post (warmed-up voice) test. Intraclass correlation coefficients were calculated to assess singers' self-ratings pre- and posttest and intra- and interlistener rater reliability. Twelve classically trained female singers recorded and self-rated their performance of an eight bar solo before and after 25 minutes of vocal warm-up exercises. Six experienced listeners assessed the vocal samples for pre- to posttest differences in tone quality and for each singer's warm-up condition. Perceptual judgements were also compared with pre- to posttest changes in vibrato. All singers perceived significant changes in tone quality, psychophysiological factors, proprioceptive feedback and technical command. Significant pre- to posttest differences in tone quality and correct appraisal of the singer's warm-up condition from most of the listeners were only observed for singers who moderated extremely fast or extremely slow vibrato after warming up. The findings reveal the divide between listeners' and singers' perceptions of the warmed-up voice and highlight the importance of enhanced vibrato quality to listener perception of an improvement in vocal quality. Copyright © 2013 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  11. Robust cloud feedback over tropical land in a warming climate

    NASA Astrophysics Data System (ADS)

    Kamae, Youichi; Ogura, Tomoo; Watanabe, Masahiro; Xie, Shang-Ping; Ueda, Hiroaki

    2016-03-01

    Cloud-related radiative perturbations over land in a warming climate are of importance for human health, ecosystem, agriculture, and industry via solar radiation availability and local warming amplification. However, robustness and physical mechanisms responsible for the land cloud feedback were not examined sufficiently because of the limited contribution to uncertainty in global climate sensitivity. Here we show that cloud feedback in general circulation models over tropical land is robust, positive, and is relevant to atmospheric circulation change and thermodynamic constraint associated with water vapor availability. In a warming climate, spatial variations in tropospheric warming associated with climatological circulation pattern result in a general weakening of tropical circulation and a dynamic reduction of land cloud during summer monsoon season. Limited increase in availability of water vapor also reduces the land cloud. The reduction of land cloud depends on global-scale oceanic warming and is not sensitive to regional warming patterns. The robust positive feedback can contribute to the warming amplification and drying over tropical land in the future.

  12. Cold climate bioventing with soil warming in Alaska

    SciTech Connect

    Sayles, G.D.; Brenner, R.C.; Leeson, A.; Hinchee, R.E.; Vogel, C.M.; Miller, R.N.

    1995-12-31

    In the heart of Alaska, a 3-year field study was conducted of bioventing in conjunction with several soil warming methods. The contamination was JP-4 jet fuel. The soil warming methods evaluated, chosen for their apparent low cost, were (1) application of warm water at a low rate, (2) enhanced solar warming by covering the surface with clear plastic in the summer and covering the surface with insulation in the winter, and (3) buried heat pipe. The warm water and buried heat tape methods performed best, maintaining summer-like 10 to 20 C temperatures in the test plots year round, compared to the temperature of the unheated control plot, which dipped to {minus}1 C in the winter. The solar/insulation warming method showed a modest improvement in temperature over the unheated control test plot. The annual average temperatures of the warm water, heat tape, solar, and control plots were 16.9, 14.5, 6.1, and 3.5 C, respectively. The biodegradation rates, measured by in situ respirometry, were higher in plots with higher temperatures and followed the Arrhenius relationship. Despite the low temperature, significant biodegradation was observed in the unheated plot during the winter.

  13. Quantifying global soil carbon losses in response to warming.

    PubMed

    Crowther, T W; Todd-Brown, K E O; Rowe, C W; Wieder, W R; Carey, J C; Machmuller, M B; Snoek, B L; Fang, S; Zhou, G; Allison, S D; Blair, J M; Bridgham, S D; Burton, A J; Carrillo, Y; Reich, P B; Clark, J S; Classen, A T; Dijkstra, F A; Elberling, B; Emmett, B A; Estiarte, M; Frey, S D; Guo, J; Harte, J; Jiang, L; Johnson, B R; Kröel-Dulay, G; Larsen, K S; Laudon, H; Lavallee, J M; Luo, Y; Lupascu, M; Ma, L N; Marhan, S; Michelsen, A; Mohan, J; Niu, S; Pendall, E; Peñuelas, J; Pfeifer-Meister, L; Poll, C; Reinsch, S; Reynolds, L L; Schmidt, I K; Sistla, S; Sokol, N W; Templer, P H; Treseder, K K; Welker, J M; Bradford, M A

    2016-11-30

    The majority of the Earth's terrestrial carbon is stored in the soil. If anthropogenic warming stimulates the loss of this carbon to the atmosphere, it could drive further planetary warming. Despite evidence that warming enhances carbon fluxes to and from the soil, the net global balance between these responses remains uncertain. Here we present a comprehensive analysis of warming-induced changes in soil carbon stocks by assembling data from 49 field experiments located across North America, Europe and Asia. We find that the effects of warming are contingent on the size of the initial soil carbon stock, with considerable losses occurring in high-latitude areas. By extrapolating this empirical relationship to the global scale, we provide estimates of soil carbon sensitivity to warming that may help to constrain Earth system model projections. Our empirical relationship suggests that global soil carbon stocks in the upper soil horizons will fall by 30 ± 30 petagrams of carbon to 203 ± 161 petagrams of carbon under one degree of warming, depending on the rate at which the effects of warming are realized. Under the conservative assumption that the response of soil carbon to warming occurs within a year, a business-as-usual climate scenario would drive the loss of 55 ± 50 petagrams of carbon from the upper soil horizons by 2050. This value is around 12-17 per cent of the expected anthropogenic emissions over this period. Despite the considerable uncertainty in our estimates, the direction of the global soil carbon response is consistent across all scenarios. This provides strong empirical support for the idea that rising temperatures will stimulate the net loss of soil carbon to the atmosphere, driving a positive land carbon-climate feedback that could accelerate climate change.

  14. Quantifying global soil carbon losses in response to warming

    NASA Astrophysics Data System (ADS)

    Crowther, T. W.; Todd-Brown, K. E. O.; Rowe, C. W.; Wieder, W. R.; Carey, J. C.; Machmuller, M. B.; Snoek, B. L.; Fang, S.; Zhou, G.; Allison, S. D.; Blair, J. M.; Bridgham, S. D.; Burton, A. J.; Carrillo, Y.; Reich, P. B.; Clark, J. S.; Classen, A. T.; Dijkstra, F. A.; Elberling, B.; Emmett, B. A.; Estiarte, M.; Frey, S. D.; Guo, J.; Harte, J.; Jiang, L.; Johnson, B. R.; Kröel-Dulay, G.; Larsen, K. S.; Laudon, H.; Lavallee, J. M.; Luo, Y.; Lupascu, M.; Ma, L. N.; Marhan, S.; Michelsen, A.; Mohan, J.; Niu, S.; Pendall, E.; Peñuelas, J.; Pfeifer-Meister, L.; Poll, C.; Reinsch, S.; Reynolds, L. L.; Schmidt, I. K.; Sistla, S.; Sokol, N. W.; Templer, P. H.; Treseder, K. K.; Welker, J. M.; Bradford, M. A.

    2016-12-01

    The majority of the Earth’s terrestrial carbon is stored in the soil. If anthropogenic warming stimulates the loss of this carbon to the atmosphere, it could drive further planetary warming. Despite evidence that warming enhances carbon fluxes to and from the soil, the net global balance between these responses remains uncertain. Here we present a comprehensive analysis of warming-induced changes in soil carbon stocks by assembling data from 49 field experiments located across North America, Europe and Asia. We find that the effects of warming are contingent on the size of the initial soil carbon stock, with considerable losses occurring in high-latitude areas. By extrapolating this empirical relationship to the global scale, we provide estimates of soil carbon sensitivity to warming that may help to constrain Earth system model projections. Our empirical relationship suggests that global soil carbon stocks in the upper soil horizons will fall by 30 ± 30 petagrams of carbon to 203 ± 161 petagrams of carbon under one degree of warming, depending on the rate at which the effects of warming are realized. Under the conservative assumption that the response of soil carbon to warming occurs within a year, a business-as-usual climate scenario would drive the loss of 55 ± 50 petagrams of carbon from the upper soil horizons by 2050. This value is around 12-17 per cent of the expected anthropogenic emissions over this period. Despite the considerable uncertainty in our estimates, the direction of the global soil carbon response is consistent across all scenarios. This provides strong empirical support for the idea that rising temperatures will stimulate the net loss of soil carbon to the atmosphere, driving a positive land carbon-climate feedback that could accelerate climate change.

  15. Warm-up affects diurnal variation in power output.

    PubMed

    Taylor, K; Cronin, J B; Gill, N; Chapman, D W; Sheppard, J M

    2011-03-01

    The purpose of this study was to examine whether time of day variations in power output can be accounted for by the diurnal fluctuations existent in body temperature. 8 recreationally trained males (29.8±5.2 yrs; 178.3±5.2 cm; 80.3±6.5 kg) were assessed on 4 occasions following a: (a) control warm-up at 8.00 am; (b) control warm-up at 4.00 pm; (c) extended warm-up at 8.00 am; and, (d) extended warm-up at 4.00 pm. The control warm-up consisted of dynamic exercises and practice jumps. The extended warm-up incorporated a 20 min general warm-up on a stationary bike prior to completion of the control warm-up, resulting in a whole body temperature increase of 0.3±0.2°C. Kinetic and kinematic variables were measured using a linear optical encoder attached to a barbell during 6 loaded counter-movement jumps. Results were 2-6% higher in the afternoon control condition than morning control condition. No substantial performance differences were observed between the extended morning condition and afternoon control condition where body temperatures were similar. Results indicate that diurnal variation in whole body temperature may explain diurnal performance differences in explosive power output and associated variables. It is suggested that warm-up protocols designed to increase body temperature are beneficial in reducing diurnal differences in jump performance.

  16. Establishing native warm season grasses on Eastern Kentucky strip mines

    SciTech Connect

    Barnes, T.G.; Larkin, J.L.; Arnett, M.B.

    1998-12-31

    The authors evaluated various methods of establishing native warm season grasses on two reclaimed Eastern Kentucky mines from 1994--1997. Most current reclamation practices incorporate the use of tall fescue (Festuca arundinacea) and other cool-season grasses/legumes that provide little wildlife habitats. The use of native warm season grasses will likely improve wildlife habitat on reclaimed strip mines. Objectives of this study were to compare the feasibility of establishing these grasses during fall, winter, or spring using a native rangeland seeder or hydroseeding; a fertilizer application at planting; or cold-moist stratification prior to hydroseeding. Vegetative cover, bare ground, species richness, and biomass samples were collected at the end of each growing season. Native warm season grass plantings had higher plant species richness compared to cool-season reclamation mixtures. There was no difference in establishment of native warm season grasses as a result of fertilization or seeding technique. Winter native warm season grass plantings were failures and cold-moist stratification did not increase plant establishment during any season. As a result of a drought during 1997, both cool-season and warm season plantings were failures. Cool-season reclamation mixtures had significantly more vegetative cover and biomass compared to native warm season grass mixtures and the native warm season grass plantings did not meet vegetative cover requirements for bond release. Forbs and legumes that established well included pale purple coneflower (Echinacea pallida), lance-leaf coreopsis (Coreopsis lanceolata), round-headed lespedeza (Lespedeza capitata), partridge pea (Cassia fasiculata), black-eyed susan (Rudbeckia hirta), butterfly milkweed (Asclepias tuberosa), and bergamot (Monarda fistulosa). Results from two demonstration plots next to research plots indicate it is possible to establish native warm season grasses on Eastern Kentucky strip mines for wildlife habitat.

  17. The impact of extratropical warming on the tropical precipitation

    NASA Astrophysics Data System (ADS)

    Yoshimori, Masakazu; Abe-Ouchi, Ayako; Tatebe, Hiroaki; Nozawa, Toru

    2017-04-01

    From paleoclimate evidence to future climate projections, it has been reported that the asymmetric warming (or cooling) between the northern and southern hemisphere extratropics induces the meridional shift in the tropical precipitation. Such a shift is often understood by the energy-flux framework in that the extra energy is transported from more warming to less warming hemispheres through the change in the Hadley circulation. As the Hadley circulation transports energy in opposite direction to the moisture, the tropical precipitation tends to be intensified in the hemisphere of a larger warming. This framework is shown to be particularly useful for modelling results without ocean dynamical feedback. In the current study, a fully coupled atmosphere-ocean model is used to investigate the impact of extratropical warming on the tropical precipitation under the realistic RCP4.5 scenario. It is shown that the mid-high latitude warming alone in the poleward of 40° (56% global warming) can significantly affect the tropical precipitation change in the equatorward of 20° (38% hemispheric contrast) from late autumn to early winter. High-latitude warming alone affects much less. This meridional change in the tropical precipitation is largely explained by the circulation change, rather than the humidity change. The reduced northward eddy momentum and heat fluxes in the northern hemisphere induces anomalous Hadley circulation in the northern tropics. This change seems to weaken the equatorial upwelling in the Pacific, which leads to the equatorial SST rise. The equatorial sea surface warming induces the meridionally symmetric pattern of the anomalous Hadley circulation (though, asymmetric in strength), resulting in the northward migration of the tropical precipitation. The larger change in the ocean heat transport near the equator, relative to the atmosphere, requires a more refined theory than the conventional energy-flux framework.

  18. Changes in Extreme Warm and Cold Temperatures Associated with 20th Century Global Warming

    NASA Astrophysics Data System (ADS)

    Sardeshmukh, P. D.; Compo, G. P.; McColl, C.; Penland, C.

    2015-12-01

    Has 20thcentury global warming resulted in increases of extreme warm temperatures and decreases of extreme cold temperatures around the globe? One would certainly expect this to be so if the changes in the extreme temperature probabilities were determined only by the mean shift and not by changes in the width and/or shape of the temperature distribution. In reality, however, the latter two effects could also be important. Even ignoring changes of shape, it is easily shown that a 25% reduction of standard deviation, for example, can completely offset the effect of a mean positive shift of 0.5 standardized units on the probabilities of extreme positive values. A 25% increase of standard deviation can similarly offset the effect of the mean shift on the probabilities of extreme negative values. It is possible for such changes of standard deviation to occur in regions of large circulation and storminess changes associated with global warming. With this caveat in mind, we have investigated the change in probability of extreme weekly-averaged near-surface air temperatures, in both winter and summer, from the first half-century (1901-1950) to the last half-century (1960-2009) of the 1901 to 2009 period. We have done this using two newly available global atmospheric datasets (ERA-20C and 20CR-v2c) and large ensembles of global coupled climate model simulations of this period, plus very large ensembles of uncoupled atmospheric model simulations of our own. The results are revealing. In the tropics, the changes in the extreme warm and cold temperature probabilities are indeed generally consistent with those expected from the mean shift of the distribution. Outside the tropics, however, they are generally significantly inconsistent with the mean temperature shift, with many regions showing little or no change in the positive temperature extremes and in some instances even a decrease. In such regions, it is clear that the change in the temperature standard deviation is

  19. Global Warming in the 21st Century: An Alternate Scenario

    NASA Technical Reports Server (NTRS)

    Hansen, James E.

    2000-01-01

    Evidence on a broad range of time scales, from Proterozoic to the most recent periods, shows that the Earth's climate responds sensitively to global forcings. In the past few decades the Earth's surface has warmed rapidly, apparently in response to increasing anthropogenic greenhouse gases in the atmosphere. The conventional view is that the current global warming rate will continue or accelerate in the 21st century. I will describe an alternate scenario that would slow the rate of global warming and reduce the danger of dramatic climate change. But reliable prediction of future climate change requires improved knowledge of the carbon cycle and global observations that allow interpretation of ongoing climate change.

  20. The dynamics of the warming hiatus over the Northern Hemisphere

    NASA Astrophysics Data System (ADS)

    Huang, Jianping; Xie, Yongkun; Guan, Xiaodan; Li, Dongdong; Ji, Fei

    2017-01-01

    A warming hiatus is a period of relatively little change in global mean surface air temperatures (SAT). Many studies have attributed the current warming hiatus to internal climate variability (ICV). But there is less work on discussion of the dynamics about how these ICV modes influence cooling over land in the Northern Hemisphere (NH). Here we demonstrate the warming hiatus was more significant over the continental NH. We explored the dynamics of the warming hiatus from a global perspective and investigated the mechanisms of the reversing from accelerated warming to hiatus, and how ICV modes influence SAT change throughout the NH land. It was found that these ICV modes and Arctic amplification can excite a decadal modulated oscillation (DMO), which enhances or suppresses the long-term trend on decadal to multi-decadal timescales. When the DMO is in an upward (warming) phase, it contributes to an accelerated warming trend, as in last 20 years of twentieth-century. It appears that there is a downward swing in the DMO occurring at present, which has balanced or reduced the radiative forced warming and resulted in the recent global warming hiatus. The DMO modulates the SAT, in particular, the SAT of boreal cold months, through changes in the asymmetric meridional and zonal thermal forcing (MTF and ZTF). The MTF represents the meridional temperature gradients between the mid- and high-latitudes, and the ZTF represents the asymmetry in temperatures between the extratropical large-scale warm and cold zones in the zonal direction. Via the different performance of combined MTF and ZTF, we found that the DMO's modulation effect on SAT was strongest when both weaker (stronger) MTF and stronger (weaker) ZTF occurred simultaneously. And the current hiatus is a result of a downward DMO combined with a weaker MTF and stronger ZTF, which stimulate both a weaker polar vortex and westerly winds, along with the amplified planetary waves, thereby facilitating southward invasion of

  1. Increasing frequency and duration of Arctic winter warming events

    NASA Astrophysics Data System (ADS)

    Graham, Robert M.; Cohen, Lana; Petty, Alek A.; Boisvert, Linette N.; Rinke, Annette; Hudson, Stephen R.; Nicolaus, Marcel; Granskog, Mats A.

    2017-07-01

    Near-surface air temperatures close to 0°C were observed in situ over sea ice in the central Arctic during the last three winter seasons. Here we use in situ winter (December-March) temperature observations, such as those from Soviet North Pole drifting stations and ocean buoys, to determine how common Arctic winter warming events are. Observations of winter warming events exist over most of the Arctic Basin. Temperatures exceeding -5°C were observed during >30% of winters from 1954 to 2010 by North Pole drifting stations or ocean buoys. Using the ERA-Interim record (1979-2016), we show that the North Pole (NP) region typically experiences 10 warming events (T2m > -10°C) per winter, compared with only five in the Pacific Central Arctic (PCA). There is a positive trend in the overall duration of winter warming events for both the NP region (4.25 days/decade) and PCA (1.16 days/decade), due to an increased number of events of longer duration.Plain Language SummaryDuring the last three winter seasons, extreme <span class="hlt">warming</span> events were observed over sea ice in the central Arctic Ocean. Each of these <span class="hlt">warming</span> events were associated with temperatures close to or above 0°C, which lasted for between 1 and 3 days. Typically temperatures in the Arctic at this time of year are below -30°C. Here we study past temperature observations in the Arctic to investigate how common winter <span class="hlt">warming</span> events are. We use time temperature observations from expeditions such as Fram (1893-1896) and manned Soviet North Pole drifting ice stations from 1937 to 1991. These historic temperature records show that winter <span class="hlt">warming</span> events have been observed over most of the Arctic Ocean. Despite a thin network of observation sites, winter time temperatures above -5°C were directly observed approximately once every 3 years in the central Arctic Ocean between 1954 and 2010. Winter <span class="hlt">warming</span> events are associated with storm systems originating in either the Atlantic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20000074249&hterms=global+warming&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dglobal%2Bwarming','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20000074249&hterms=global+warming&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dglobal%2Bwarming"><span>Global <span class="hlt">Warming</span> in the 21st Century: An Alternate Scenario</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hansen, James E.</p> <p>2000-01-01</p> <p>Evidence on a broad range of time scales, from Proterozoic to the most recent periods, shows that the Earth's climate responds sensitively to global forcings. In the past few decades the Earth's surface has <span class="hlt">warmed</span> rapidly, apparently in response to increasing anthropogenic greenhouse gases in the atmosphere. The conventional view is that the current global <span class="hlt">warming</span> rate will continue or accelerate in the 21st century. I will describe an alternate scenario that would slow the rate of global <span class="hlt">warming</span> and reduce the danger of dramatic climate change. But reliable prediction of future climate change requires improved knowledge of the carbon cycle and global observations that allow interpretation of ongoing climate change.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20889150','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20889150"><span>Population risk perceptions of global <span class="hlt">warming</span> in Australia.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Agho, Kingsley; Stevens, Garry; Taylor, Mel; Barr, Margo; Raphael, Beverley</p> <p>2010-11-01</p> <p>According to the World Health Organisation (WHO), global <span class="hlt">warming</span> has the potential to dramatically disrupt some of life's essential requirements for health, water, air and food. Understanding how Australians perceive the risk of global <span class="hlt">warming</span> is essential for climate change policy and planning. The aim of this study was to determine the prevalence of, and socio-demographic factors associated with, high levels of perceived likelihood that global <span class="hlt">warming</span> would worsen, concern for self and family and reported behaviour changes. A module of questions on global <span class="hlt">warming</span> was incorporated into the New South Wales Population Health Survey in the second quarter of 2007. This Computer Assisted Telephone Interview (CATI) was completed by a representative sample of 2004 adults. The weighted sample was comparable to the Australian population. Bivariate and multivariate statistical analyses were conducted to examine the socio-demographic and general health factors. Overall 62.1% perceived that global <span class="hlt">warming</span> was likely to worsen; 56.3% were very or extremely concerned that they or their family would be directly affected by global <span class="hlt">warming</span>; and 77.6% stated that they had made some level of change to the way they lived their lives, because of the possibility of global <span class="hlt">warming</span>. After controlling for confounding factors, multivariate analyses revealed that those with high levels of psychological distress were 2.17 (Adjusted Odds Ratio (AOR)=2.17; CI: 1.16-4.03; P=0.015) times more likely to be concerned about global <span class="hlt">warming</span> than those with low psychological distress levels. Those with a University degree or equivalent and those who lived in urban areas were significantly more likely to think that global <span class="hlt">warming</span> would worsen compared to those without a University degree or equivalent and those who lived in the rural areas. Females were significantly (AOR=1.69; CI: 1.23-2.33; P=0.001) more likely to report they had made changes to the way they lived their lives due to the risk of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16946033','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16946033"><span>Global genetic change tracks global climate <span class="hlt">warming</span> in Drosophila subobscura.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Balanyá, Joan; Oller, Josep M; Huey, Raymond B; Gilchrist, George W; Serra, Luis</p> <p>2006-09-22</p> <p>Comparisons of recent with historical samples of chromosome inversion frequencies provide opportunities to determine whether genetic change is tracking climate change in natural populations. We determined the magnitude and direction of shifts over time (24 years between samples on average) in chromosome inversion frequencies and in ambient temperature for populations of the fly Drosophila subobscura on three continents. In 22 of 26 populations, climates <span class="hlt">warmed</span> over the intervals, and genotypes characteristic of low latitudes (<span class="hlt">warm</span> climates) increased in frequency in 21 of those 22 populations. Thus, genetic change in this fly is tracking climate <span class="hlt">warming</span> and is doing so globally.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009JCAP...06..002M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009JCAP...06..002M"><span>Evolution of the curvature perturbations during <span class="hlt">warm</span> inflation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Matsuda, Tomohiro</p> <p>2009-06-01</p> <p>This paper considers <span class="hlt">warm</span> inflation as an interesting application of multi-field inflation. Delta-N formalism is used for the calculation of the evolution of the curvature perturbations during <span class="hlt">warm</span> inflation. Although the perturbations considered in this paper are decaying after the horizon exit, the corrections to the curvature perturbations sourced by these perturbations can remain and dominate the curvature perturbations at large scales. In addition to the typical evolution of the curvature perturbations, inhomogeneous diffusion rate is considered for <span class="hlt">warm</span> inflation, which may lead to significant non-Gaussianity of the spectrum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009mavo.proc..185N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009mavo.proc..185N"><span>HS 1603+3820 and its <span class="hlt">Warm</span> Absorber</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nikołajuk, M.; Różańska, A.; Czerny, B.; Dobrzycki, A.</p> <p>2009-07-01</p> <p>We use photoionization codes CLOUDY and TITAN to obtain physical conditions in the absorbing medium close to the nucleus of a distant quasar (z = 2.54) HS 1603+3820. We found that the total column density of this <span class="hlt">Warm</span> Absorber is 2 x 1022 cm-2. Due to the softness of the quasars spectrum the modelling allowed us also to determine uniquely the volume hydrogen density of this <span class="hlt">warm</span> gas (n = 1010 cm-3) which combined with the other quasar parameters leads to a distance determination to the <span class="hlt">Warm</span> Absorber from the central source which is ~ 1.5 x 1016 cm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EOSTr..94..142S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EOSTr..94..142S"><span>Majority of Americans Believe Global <span class="hlt">Warming</span> Is Occurring, Survey Shows</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Showstack, Randy</p> <p>2013-04-01</p> <p>Seventy-eight percent of the American public believe that global <span class="hlt">warming</span> has been occurring, according to a 2012 survey presented by Jon Krosnick, senior fellow with the Stanford Woods Institute for the Environment, at a 28 March briefing on Capitol Hill on the trajectory of public perceptions about global <span class="hlt">warming</span> and government involvement in the issue. While the percentage has varied from 75% to 85% since 1997, the survey results "contradict any claims that Americans have turned away from this issue in large numbers," said Krosnick, who is also the Frederic O. Glover Professor in Humanities and Social Sciences at Stanford University, Calif. "They still believe that <span class="hlt">warming</span> has been happening."</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.C21C0456T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.C21C0456T"><span><span class="hlt">Warm</span> Oceans, Fast Glaciers: the connections</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Truffer, M.; Fahnestock, M. A.; Amundson, J. M.</p> <p>2009-12-01</p> <p>Over the last decade many outlet glaciers from the Greenland Ice Sheet have accelerated and thinned, and in a number of cases their termini have retreated. There is much in common from glacier to glacier that emerges as these changes are studied, yet the actual physical mechanisms remain unclear. One can show that the spatial patterns and timing of outlet glacier changes around Greenland coincide with changes in sea surface temperature and length of the sea-ice-free season in the surrounding ocean, and that large glacier changes appear to initiate within one to a few years of shifts in these conditions. While ocean <span class="hlt">warming</span> has a direct impact on rates of melting at the glacier ice/ocean interface, its impact on ice flow is less direct. The spatial and temporal coincidence between changing ocean conditions and speedup is compelling, but the causal link between warmer ocean water and rapid responses from outlet glaciers around Greenland is more complex. Observations of rapid calving retreats, the appearance of calving-related long-period seismicity at some large glaciers undergoing change, and the loss of floating ice tongues all suggest that the direct impact of ocean-driven change is on the stability of the lowest reach of these tidewater outlets. In glaciers with a floating tongue, enhanced basal melt may be destabilizing by thinning the tongue to below its structural integrity; at grounded termini this effect is lacking. However, rapid melt at the near-vertical face can play a significant role for slowly flowing systems. For large grounded glaciers with terminus flow rates of meters per day, the impact of increased melt in summer would seem less important. At such glaciers the link between ocean temperatures, sea ice cover and terminus stability manifests itself by the cessation of calving in fall and winter, which leads to terminus advance and the formation of a floating tongue. The loss of sea ice cover in early spring leads to a disintegration of the seasonal</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19980037619','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19980037619"><span>Global <span class="hlt">Warming</span> Estimation From Microwave Sounding Unit</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Prabhakara, C.; Iacovazzi, R., Jr.; Yoo, J.-M.; Dalu, G.</p> <p>1998-01-01</p> <p>Microwave Sounding Unit (MSU) Ch 2 data sets, collected from sequential, polar-orbiting, Sun-synchronous National Oceanic and Atmospheric Administration operational satellites, contain systematic calibration errors that are coupled to the diurnal temperature cycle over the globe. Since these coupled errors in MSU data differ between successive satellites, it is necessary to make compensatory adjustments to these multisatellite data sets in order to determine long-term global temperature change. With the aid of the observations during overlapping periods of successive satellites, we can determine such adjustments and use them to account for the coupled errors in the long-term time series of MSU Ch 2 global temperature. In turn, these adjusted MSU Ch 2 data sets can be used to yield global temperature trend. In a pioneering study, Spencer and Christy (SC) (1990) developed a procedure to derive the global temperature trend from MSU Ch 2 data. Such a procedure can leave unaccounted residual errors in the time series of the temperature anomalies deduced by SC, which could lead to a spurious long-term temperature trend derived from their analysis. In the present study, we have developed a method that avoids the shortcomings of the SC procedure, the magnitude of the coupled errors is not determined explicitly. Furthermore, based on some assumptions, these coupled errors are eliminated in three separate steps. Such a procedure can leave unaccounted residual errors in the time series of the temperature anomalies deduced by SC, which could lead to a spurious long-term temperature trend derived from their analysis. In the present study, we have developed a method that avoids the shortcomings of the SC procedures. Based on our analysis, we find there is a global <span class="hlt">warming</span> of 0.23+/-0.12 K between 1980 and 1991. Also, in this study, the time series of global temperature anomalies constructed by removing the global mean annual temperature cycle compares favorably with a similar</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22356665','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22356665"><span>Experiments of water formation on <span class="hlt">warm</span> silicates</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>He, Jiao; Vidali, Gianfranco</p> <p>2014-06-10</p> <p>When dust grains have a higher temperature than they would have in dense clouds, and when H, H{sub 2}, and O{sub 2} have a negligible residence time on grains, the formation of water should still be possible via the hydrogenation of OH and Eley-Rideal-type reactions. We determined that the OH desorption energy from an amorphous silicate surface is at least 143 meV (1656 K). This is 400 K higher than the value previously used in chemical models of the interstellar medium and is possibly as high as 410 meV (4760 K). This extends the temperature range for the efficient formation of water on grains from about 30 K to at least 50 K, and possibly over 100 K. We do not find evidence that water molecules leave the surface upon formation. Instead, through a thermal programmed desorption experiment, we find that water formed on the surface of an amorphous silicate desorbs at around 160 K. We also measured the cross-sections for the reaction of H and D with an O{sub 3} layer on an amorphous silicate surface at 50 K. The values of the cross-sections, σ{sub H} = 1.6 ± 0.27 Å{sup 2} and σ{sub D} = 0.94 ± 0.09 Å{sup 2}, respectively, are smaller than the size of an O{sub 3} molecule, suggesting the reaction mechanism is more likely Eley-Rideal than hot-atom. Information obtained through these experiments should help theorists evaluate the relative contribution of water formation on <span class="hlt">warm</span> grains versus in the gas phase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21680496','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21680496"><span>Polar bears in a <span class="hlt">warming</span> climate.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Derocher, Andrew E; Lunn, Nicholas J; Stirling, Ian</p> <p>2004-04-01</p> <p>Polar bears (Ursus maritimus) live throughout the ice-covered waters of the circumpolar Arctic, particularly in near shore annual ice over the continental shelf where biological productivity is highest. However, to a large degree under scenarios predicted by climate change models, these preferred sea ice habitats will be substantially altered. Spatial and temporal sea ice changes will lead to shifts in trophic interactions involving polar bears through reduced availability and abundance of their main prey: seals. In the short term, climatic <span class="hlt">warming</span> may improve bear and seal habitats in higher latitudes over continental shelves if currently thick multiyear ice is replaced by annual ice with more leads, making it more suitable for seals. A cascade of impacts beginning with reduced sea ice will be manifested in reduced adipose stores leading to lowered reproductive rates because females will have less fat to invest in cubs during the winter fast. Non-pregnant bears may have to fast on land or offshore on the remaining multiyear ice through progressively longer periods of open water while they await freeze-up and a return to hunting seals. As sea ice thins, and becomes more fractured and labile, it is likely to move more in response to winds and currents so that polar bears will need to walk or swim more and thus use greater amounts of energy to maintain contact with the remaining preferred habitats. The effects of climate change are likely to show large geographic, temporal and even individual differences and be highly variable, making it difficult to develop adequate monitoring and research programs. All ursids show behavioural plasticity but given the rapid pace of ecological change in the Arctic, the long generation time, and the highly specialised nature of polar bears, it is unlikely that polar bears will survive as a species if the sea ice disappears completely as has been predicted by some.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5827970','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5827970"><span>Report nixes Geritol fix for global <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Roberts, L.</p> <p>1991-09-27</p> <p>Several years ago John Martin of the Moss Landing Marine Laboratory in California suggested a quick fix to the greenhouse problem: dump iron into the Southern Ocean near Antarctica. That, he said, would trigger a massive bloom of the ocean's microscopic plants, which in turn would suck carbon dioxide out of the atmosphere and help reduce global <span class="hlt">warming</span>. His idea ignited a firestorm of controversy that rages on today. While the idea quickly won supporters - including some prominent members of the National Academy of Sciences - much of the oceanographic community was incensed, arguing that you don't tinker with a perfectly health ecosystem to clean up humanity's mess. Now the American Society of Limnology and Oceanography (ASLO) has a report that represents the views of much of the oceanographic community. In the report, released in late summer, ASLO trounces the idea of fertilizing the oceans with iron as a greenhouse fix, as expected. But in an unexpected twist, the society endorses a small-scale experiment in which iron would be added to the open ocean. The idea isn't to engineer the oceans, but to test the hypothesis that might answer one of the longstanding puzzles in biological oceanography: why do the phytoplankton of the Southern Ocean, as well as those in parts of the subarctic and equatorial Pacific, grow so poorly, even though the waters are rich in nutrients such as phosphorus and nitrogen The answer could shed light not only on how the food web operates, but on the global carbon cycle as well.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.2086F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.2086F"><span>Heat waves and <span class="hlt">warm</span> periods in Slovakia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Faško, Pavel; Bochníček, Oliver; Markovič, Ladislav; Švec, Marek</p> <p>2016-04-01</p> <p>The scenarios of climate change caused by human activity show that frequency of occurrence and extent of heat waves in the interior of Europe is increasing. Among the most exposed regions in this regard should the area of southeastern and eastern Austria and south-western Slovakia. The relatively faster increase in the number of heat waves in this area is related also to potential desertification in this region just east of the Alps, since during summer, weather fronts advancing from the west are consequently losing their original features and moderating influence. Summer weather patterns for this area should in the future more closely remind climate typical for some inland areas of southwestern, southern and southeastern Europe. A certain shift of climate zones from south to north should thus modify future climate and Slovakia. Despite the complex natural conditions the existing trends derived from results of meteorological measurements and observations are clear and they confirm <span class="hlt">warming</span> of climate in this region. Observations and measurements in the recent years of the 21st century confirm, that heat waves are no longer rare phenomenon during summer, but are systematically appearing even in colder regions of northern Slovakia. What is very remarkable and will be necessary to pay more attention to, is the fact that these heat waves are expanding into previously unaffected areas, associated with the lack of rainfall and drought, on larger regional scale. In this study heat wave periods and individual heat events and days are statistically identified in the time series characteristics of air temperature at selected meteorological stations for the period from the mid-20th century until 2015, in case of available historical data even for longer period.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22365827','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22365827"><span><span class="hlt">WARM</span> MOLECULAR GAS IN LUMINOUS INFRARED GALAXIES</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lu, N.; Zhao, Y.; Xu, C. K.; Mazzarella, J. M.; Howell, J.; Appleton, P.; Lord, S.; Schulz, B.; Gao, Y.; Armus, L.; Díaz-Santos, T.; Surace, J.; Isaak, K. G.; Petric, A. O.; Charmandaris, V.; Evans, A. S.; Inami, H.; Iwasawa, K.; Leech, J.; Sanders, D. B.; and others</p> <p>2014-06-01</p> <p>We present our initial results on the CO rotational spectral line energy distribution (SLED) of the J to J–1 transitions from J = 4 up to 13 from Herschel SPIRE spectroscopic observations of 65 luminous infrared galaxies (LIRGs) in the Great Observatories All-Sky LIRG Survey. The observed SLEDs change on average from one peaking at J ≤ 4 to a broad distribution peaking around J ∼ 6 to 7 as the IRAS 60-to-100 μm color, C(60/100), increases. However, the ratios of a CO line luminosity to the total infrared luminosity, L {sub IR}, show the smallest variation for J around 6 or 7. This suggests that, for most LIRGs, ongoing star formation (SF) is also responsible for a <span class="hlt">warm</span> gas component that emits CO lines primarily in the mid-J regime (5 ≲ J ≲ 10). As a result, the logarithmic ratios of the CO line luminosity summed over CO (5–4), (6–5), (7–6), (8–7) and (10–9) transitions to L {sub IR}, log R {sub midCO}, remain largely independent of C(60/100), and show a mean value of –4.13 (≡log R{sub midCO}{sup SF}) and a sample standard deviation of only 0.10 for the SF-dominated galaxies. Including additional galaxies from the literature, we show, albeit with a small number of cases, the possibility that galaxies, which bear powerful interstellar shocks unrelated to the current SF, and galaxies, in which an energetic active galactic nucleus contributes significantly to the bolometric luminosity, have their R {sub midCO} higher and lower than R{sub midCO}{sup SF}, respectively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26227528','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26227528"><span>Comparing new-technology passive <span class="hlt">warming</span> versus traditional passive <span class="hlt">warming</span> methods for optimizing perioperative body core temperature.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bender, Miriam; Self, Beverly; Schroeder, Ellen; Giap, Brandon</p> <p>2015-08-01</p> <p>Hypothermia puts surgical patients at risk for adverse outcomes. Traditional passive <span class="hlt">warming</span> methods are mostly ineffective in reducing hypothermia. New-technology passive <span class="hlt">warming</span> holds promise as an effective method for promoting and sustaining normothermia throughout surgery. The purpose of this retrospective cohort study was to compare the effectiveness of new-technology passive <span class="hlt">warming</span> with traditional methods. We measured core body temperature at anesthesia induction and at the end of surgery for patients undergoing robotic-assisted prostatectomy/hysterectomy in the lithotomy position who received either new-technology passive <span class="hlt">warming</span> (n = 30) or traditional linens and gel pads (n = 35). The traditionally <span class="hlt">warmed</span> cohort had no change in temperature (35.9° C ± 0.6° C presurgery vs 35.9° C ± 0.7° C postsurgery; t = 0.47; P = .66). The intervention cohort showed a significant increase in temperature (35.75° C ± 0.52° C presurgery vs 36.30° C ± 0.53° C postsurgery; t = 4.64; P < .001). A repeated-measure analysis of variance adjusting for surgery duration and fluid administration confirmed the significance (F = 17.254; P < .001), suggesting that new-technology passive <span class="hlt">warming</span> may effectively complement active <span class="hlt">warming</span> to reduce perioperative hypothermia.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15819747','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15819747"><span>Keeping <span class="hlt">warm</span> and staying well: findings from the qualitative arm of the <span class="hlt">Warm</span> Homes Project.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Harrington, Barbara E; Heyman, Bob; Merleau-Ponty, Nick; Stockton, H; Ritchie, Neil; Heyman, Anna</p> <p>2005-05-01</p> <p>This paper presents findings from the qualitative arm of the <span class="hlt">Warm</span> Homes Project, a programme of research concerned with the nature of fuel poverty, its alleviation and its relationship to family health. Much of the research into fuel poverty, which results from various combinations of low income and fuel inefficiency, has drawn upon quantitative paradigms. Experiences of, and coping with, fuel poverty have not been well explored. Data for the present study were obtained through qualitative interviews with household members about the above issues. The findings suggest that the expectations of those in fuel poverty about staying <span class="hlt">warm</span>, and their beliefs about the relationship between warmth and health, vary considerably. Fuel poverty often had wider ramifications, impacting on quality of life in complex ways. The respondents took steps to alleviate cold, but their strategies varied. Coping was affected by informational limitations as well as cost constraints. Measures designed to alleviate fuel poverty should take into account its wider social meaning within the lives of household members.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Cabbage&id=EJ373998','ERIC'); return false;" href="http://eric.ed.gov/?q=Cabbage&id=EJ373998"><span>The <span class="hlt">Warm</span>-Blooded Plant of the Swamps.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Camazine, Scott</p> <p>1986-01-01</p> <p>Describes remarkable characteristics of the skunk cabbage (Symplocarpus foetidus) which make it an interesting swamp plant to study in February and March: its <span class="hlt">warm</span>-blooded nature, unpleasant skunky odor, and peculiar root system. (NEC)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060035752&hterms=global+warming+causes&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dglobal%2Bwarming%2Bcauses','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060035752&hterms=global+warming+causes&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dglobal%2Bwarming%2Bcauses"><span>Optimal Detection of Global <span class="hlt">Warming</span> using Temperature Profiles</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Leroy, Stephen S.</p> <p>1997-01-01</p> <p>Optimal fingerprinting is applied to estimate the amount of time it would take to detect <span class="hlt">warming</span> by increased concentrations of carbon dioxide in monthly averages of temperature profiles over the Indian Ocean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-PIA18034.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-PIA18034.html"><span><span class="hlt">Warm</span> Rivers Play Role in Arctic Sea Ice Melt</span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2014-03-05</p> <p>Beaufort Sea surface temperatures where Canada Mackenzie River discharges into the Arctic Ocean, measured by NASA MODIS instrument; <span class="hlt">warm</span> river waters had broken through a shoreline sea ice barrier to enhance sea ice melt.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060035752&hterms=global+warming&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dglobal%2Bwarming','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060035752&hterms=global+warming&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dglobal%2Bwarming"><span>Optimal Detection of Global <span class="hlt">Warming</span> using Temperature Profiles</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Leroy, Stephen S.</p> <p>1997-01-01</p> <p>Optimal fingerprinting is applied to estimate the amount of time it would take to detect <span class="hlt">warming</span> by increased concentrations of carbon dioxide in monthly averages of temperature profiles over the Indian Ocean.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_25 --> <center> <div class="footer-extlink text-muted"><small>Some links on this page may take you to non-federal websites. 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