bluuebunny/crossref_metadata_2025 huggingface dataset:
Low population density of a tropical forest carnivore, Cryptoprocta ferox: implications for protected area management
Authors: Hawkins Clare E. , Racey Paul A.
Published: January 2005

The widespread geographical distributions of mammalian carnivores such as the Carnivora and the Dasyuridae have often been erroneously equated with abundance. Their low densities and high demands on habitat area can render mammalian carnivores especially vulnerable to habitat fragmentation and destruction. The fossa Cryptoprocta ferox (Viverridae) is a mammalian carnivore threatened by the rapid loss of Madagascar's forests, to which it is endemic. A 3-year mark-recapture study, comprising four censuses, generated an estimate of fossa population density at 0.18 adults km−2, or 0.26 individuals km−2. This was supported by a similar estimate from home range data. The fossa is thought to be unusually common in the study area, yet the estimated density was lower than that predicted for a typical tropical carnivorous mammal of the body mass of a fossa. Ecologists are frequently under pressure to provide estimates of local and global population numbers of their study species; we discuss the numerous factors that limit our ability to do this on the basis of a single population estimate. Nonetheless, our findings are sufficient to suggest that none of Madagascar's 46 protected areas supports a viable population of fossas, indicating a demand for corridors and enlarged reserves to ensure this species' long-term survival. Loss of the top predator can have a knock-on effect on an ecosystem. The findings indicate that, to maintain intact tropical forest ecosystems, it may be essential to consider the requirements of their often little-known mammalian carnivores. These requirements could be far greater than previously assumed.
Reintroduction increased vitamin E and condition in captive-bred yellow-footed rock wallabies Petrogale xanthopus
Authors: Lapidge Steven J.
Published: January 2005

Welfare implications of reintroduction are primarily unknown, although reportedly negative. Few studies have described physiological changes in captive-bred animals post-release and consequently the impact of reintroduction on captive-bred animals is not well understood. Such information is crucial to understanding whether reintroduction constitutes ethical practice. For these reasons two physiological indices associated with animal health, plasma vitamin E concentration (PVEC) or α-Tocopherol, and general condition scores, were monitored in reintroduced captive-bred yellow-footed rock wallabies Petrogale xanthopus celeris and P. x. xanthopus pre- and post-release. PVEC was chosen because deficiencies are common in captive animals compared to their wild counterparts, and have been linked to stress, myopathy, neuronal degeneration, low reproduction, anaemia and death. Changes in physical condition, within this study indicated principally by mass variation, coat condition, and reproductive status, but also parasite load, visible stress, lethargy and diarrhoea, have also not been reported for captive-bred animals reintroduced to the wild. Captive-bred yellow-footed rock wallabies reintroduced to areas of their former range in Queensland and South Australia showed a rapid and sustained increase in PVEC and physical condition, with post-release values significantly higher than pre-release captive levels. Post-release values for both parameters did not significantly differ from that of wild counterparts. Hence I conclude that there was no welfare implications related to the observed parameters in these reintroductions, rather the opposite.
Updated estimates of biotic diversity and endemism for Madagascar
Authors: Goodman Steven M. , Benstead Jonathan P.
Published: January 2005

Madagascar is a critical priority for international conservation efforts, based on almost unparalleled levels of endemism, species diversity, and human threat. Field research conducted over the past two decades has greatly expanded knowledge of the island's biota, making it difficult for any single research team to maintain up to date estimates of biodiversity and endemism across taxonomic groups. The recent publication of The Natural History of Madagascar, a synthesis by nearly 300 contributors from a wide range of disciplines, provides the means to update these estimates. Here, we summarize biodiversity information presented in the volume by providing revised estimates of species richness, endemism, and state of knowledge of a wide variety of taxonomic groups occurring on the island.
Fishes of the Salonga National Park, Democratic Republic of Congo: survey and conservation issues
Authors: Inogwabini Bila-Isia
Published: January 2005

Data were collected on the species richness and abundance of fishes at two sites in the Salonga National Park, Democratic Republic of Congo. Thirty species were identified out of a total of 1,180 fish caught. Claria buthupogon and Synodontis nigriventris (respectively 4.7 and 3.5 catches per net-night) were the most abundant species. Twenty-six other fish species were reported from interviews with local people. Conservation concerns are the burning of breeding sites, use of chemicals for fishing, and the newly introduced practice of dynamite fishing. The effects of these practices in the Park have yet to be documented, but it is likely that these fishing techniques are having negative effects on the fish fauna and urgent action is required to curb such activities, at least within the Park.
The IUCN Technical Guidelines on the Management of Ex Situ Populations for Conservation: reflecting major changes in the application of ex situ conservation
Authors: Maunder Mike , Byers Onnie
Published: January 2005

The recently revised IUCN Technical Guidelines on the Management of Ex Situ Populations for Conservation represent an attempt to synthesize current thinking on the strategic application of ex situ conservation for the maximum benefit of both threatened species and habitats. We review this document as a means of assessing major changes in the application of ex situ conservation. We identify a number of major themes. These include the need for the integrated management of wild and captive populations, expansion of ex situ capacity in terms of institutional facilities and breadth of taxonomic experience, an important emphasis to be given to the need for in-country conservation initiatives, and the need to comply with national and international legal structures, most notably the Convention on Biological Diversity.
History: changing the forms or forming the changes?
Authors: LARSEN SVEND ERIK
Published: January 2005

Change in European cultural history has, for a long period, been discussed through two interrelated notions, that of science and that of history. This paper traces the various stages of this discussion from Antiquity to the present day from the point of view of history. Two reoccurring and paradigmatic characters of mythological descent, Odysseus and Prometheus, illustrate how history as a realm for human responsibility and future planning has established itself as a specific European construct, with the 18th century as its final breakthrough in practical and ideological terms. A close analysis of Leonardo da Vinci's drawing the Vitruvian Man, in statu nascendi, shows how the individual human being carrying the obligations and the promises of this history, is envisioned. The final remarks underline the importance of scientific knowledge in the concrete shaping of this responsibility and a plea for an increased cooperation across the disciplines.
Racination and ratiocination: post-colonial crime
Authors: MORSE RUTH
Published: January 2005

Crime fiction is currently one of the most globalized, most popular, and biggest-selling of commercial genres, but there has been almost no attempt to study it in relation to other kinds of post-colonial literature. There is no bibliography of crime writers as ‘post-colonial’, and no attempt to generalize about a body of fiction. This paper is a brief extract from work in progress, based on the books of over fifty Anglophone or Francophone authors who might be categorized as ‘post-colonial’ by birth or residence. I test post-colonial theory against crime fiction, to argue that strong generic conventions call into question some of that theory's received ideas. I consider two linked problems: first, so-called ‘colonial mimicry’ and its obverse, ‘ventriloquism’, because it seems to me a wrong turning in 20th-century criticism; and, second, the demand for new literatures which would create ‘national identities’. I argue that ‘mimicry’ makes no sense in the context of a strong popular genre, and that accusations of ‘colonial mimicry’ reinscribe the asymmetries of judgement they appear to attack. The possibility of imagined geopolitical units as identity-forming, especially in genres which are informed by social criticism, calls into question the demand for literature as a source of national identity.
Europe and post-colonial creativity: a metaphysical cross-culturalism
Authors: MAES-JELINEK HENA
Published: January 2005

In Shakespeare's The Tempest, the meeting between Prospero and Caliban is an allegory of a Renaissance colonial encounter. Although Prospero emphasizes his gift of language to Caliban, he deems him incapable of ‘nurture’ (cultural progress). After the Second World War, the Barbadian novelist Georges Lamming saw in that gift the possibility of a ‘new departure’, which in the following decades was to modify not only Caliban's prospects but most emphatically the European, and specifically, the British cultural scene. I intend to illustrate this transformation through the contribution of postcolonial writers to the metamorphosis of the ‘Great Tradition’ of the English novel. The changes are formal, linguistic but also evince a metaphysical cross-culturalism best exemplified, among others, in the fiction of the Guyanese-born, British novelist Wilson Harris.
Differences in olfactory and visual memory in patients with pathologically confirmed Alzheimer's disease and the Lewy body variant of Alzheimer's disease
Authors: GILBERT PAUL E. , BARR P. JOYCE , MURPHY CLAIRE
Published: January 2005

Recognition and remote memory for odors, faces, and symbols were assessed in patients with pathologically confirmed Lewy body variant of Alzheimer's disease (LBV), patients with pathologically confirmed Alzheimer's disease (AD), and healthy elderly controls. On recognition memory tasks, LBV and AD patients showed significantly lower discriminability (d′) than controls, particularly for olfactory stimuli. However no significant differences were found in the bias measure (c). When participants rated familiarity (a proposed measure of remote memory) of olfactory stimuli LBV and AD patients reported significantly lower familiarity than controls. Familiarity ratings were significantly lower in LBV patients than in AD patients for olfactory, but not for visual stimuli. Consistent with prior reports, the LBV patients showed significantly poorer odor thresholds than AD patients. The results suggest that recognition memory for olfactory stimuli is impaired in LBV and AD. However, patients with LBV are more impaired than patients with AD on tasks requiring remote memory for olfactory but not visual stimuli. The findings suggest that odor memory tasks may be useful in the assessment of LBV and AD. (JINS, 2004,10, 835–842.)
Semantic and phonological processing in illiteracy
Authors: KOSMIDIS MARY H. , TSAPKINI KYRANA , FOLIA VASILIKI , VLAHOU CHRISTINA H. , KIOSSEOGLOU GRIGORIS
Published: January 2005

Researchers of cognitive processing in illiteracy have proposed that the acquisition of literacy modifies the functional organization of the brain. They have suggested that, while illiterate individuals have access only to innate semantic processing skills, those who have learned the correspondence between graphemes and phonemes have several mechanisms available to them through which to process oral language. We conducted 2 experiments to verify that suggestion with respect to language processing, and to elucidate further the differences between literate and illiterate individuals in the cognitive strategies used to process oral language, as well as hemispheric specialization for these processes. Our findings suggest that semantic processing strategies are qualitatively the same in literates and illiterates, despite the fact that overall performance is augmented by increased education. In contrast, explicit processing of oral information based on phonological characteristics appears to be qualitatively different between literates and illiterates: effective strategies in the processing of phonological information depend upon having had a formal education, regardless of the level of education. We also confirmed the differential abilities needed for the processing of semantic and phonological information and related them to hemisphere-specific processing. (JINS, 2004,10, 818–827.)
Standard error in the Jacobson and Truax Reliable Change Index: The
“classical approach” leads to poor estimates
Authors: TEMKIN NANCY R.
Published: January 2005

Different authors have used different estimates of variability in the
denominator of the Reliable Change Index (RCI). Maassen attempts to
clarify some of the differences and the assumptions underlying them. In
particular he compares the ‘classical’ approach using an
estimate SEd supposedly based on measurement error
alone with an estimate SDiff based on the
variability of observed differences in a population that should have no
true change. Maassen concludes that not only is SEd
based on classical theory, but it properly estimates variability due to
measurement error and practice effect while SDiff
overestimates variability by accounting twice for the variability due
to practice. Simulations show Maassen to be wrong on both accounts.
With an error rate nominally set to 10%, RCI estimates using
SDiff wrongly declare change in 10.4% and 9.4% of
simulated cases without true change while estimates using
SEd wrongly declare change in 17.5% and 12.3% of the
simulated cases (p < .000000001 and p < .008,
respectively). In the simulation that separates measurement error and
practice effects, SEd estimates the variability of
change due to measurement error to be .34, when the true variability
due to measurement error was .014. Neuropsychologists should not use
SEd in the denominator of the RCI. (JINS,
2004, 10, 899–901.)
Spatial memory deficits in patients after unilateral selective
amygdalohippocampectomy
Authors: KESSELS ROY P.C. , HENDRIKS MARC P.H. , SCHOUTEN JACOB , VAN ASSELEN MARIEKE , POSTMA ALBERT
Published: January 2005

The present study investigated the differential involvement of the
right and left hippocampus in various forms of spatial memory: spatial
search, positional memory versus object–location
binding, and coordinate versus categorical processing.
Twenty-five epilepsy patients with selective amygdalohippocampectomy
were examined using a sensitive computer paradigm to measure these
spatial memory aspects. The patients' performance was compared to
a group of thirty healthy controls. The results show that the left
amygdalohippocampectomy group performed poorly on the ability to bind
together object information to coordinate spatial locations. In turn,
the right amygdalohippocampectomy group was impaired in coordinate
positional memory. Both patient groups were unimpaired on the spatial
search task. These findings are discussed focusing on the
“binding device” hypothesis in combination with the
cognitive map theory. (JINS, 2004, 10,
907–912.)
Cognitive impulsivity and HIV serostatus in substance dependent
males
Authors: MARTIN EILEEN M. , PITRAK DAVID L. , WEDDINGTON WILLIAM , RAINS NILES A. , NUNNALLY GERALD , NIXON HEATHER , GRBESIC SILVANA , VASSILEVA JASMIN , BECHARA ANTOINE
Published: January 2005

HIV-seropositive (HIV+) drug users show impaired performance on
measures of integrity of prefrontal–subcortical systems. The Iowa
Gambling Task (GT) is mediated primarily through
ventromedial–prefrontal systems, and poor performance on this
measure (“cognitive impulsivity”) is common among substance
dependent individuals (SDIs) as well as patients with disease involving
prefrontal–subcortical systems (e.g., Huntington disease). We
hypothesized that HIV+ SDIs might be more vulnerable to cognitive
impulsivity when compared with HIV-seronegative (HIV−) SDIs
because recent studies report evidence of additive effects of HIV
serostatus and drug dependence on cognition. Further, working memory is
considered a key component of GT performance and is reliably impaired
among HIV+ SDIs compared to controls. We administered the GT to 46 HIV+
and 47 well-matched HIV− males with a past or current history of
substance dependence. In addition, we evaluated correlations between
subjects' scores on the GT and on a delayed nonmatch to sample
(DNMS) task in order to test if working memory deficits accounted for
cognitive impulsivity among the HIV+ subjects. The HIV+ subjects
performed significantly more poorly on the GT compared to the
HIV− group but this effect could not be explained by working
memory deficits. Implications of these findings for future basic and
applied studies of HIV and substance dependence are discussed.
(JINS, 2004, 10, 931–938.)
Neuropsychological effects of pediatric obstructive sleep apnea
Authors: BEEBE DEAN W. , WELLS CAROLYN T. , JEFFRIES JENNIFER , CHINI BARBARA , KALRA MANINDER , AMIN RAOUF
Published: January 2005

Obstructive sleep apnea (OSA) is a fairly common nocturnal breathing disorder, affecting 2–4% of individuals. Although OSA is associated with medical morbidity, its most functionally disruptive effects in adults appear to be neuropsychological in nature. Research on the neuropsychological effects of pediatric OSA has been limited. This study compared the neuropsychological functioning of school-aged children with OSA to that of healthy children. The primary goal was to clarify the presence and pattern of neuropsychological morbidity associated with pediatric OSA. Sleep was assessed with parent-report questionnaires and laboratory sleep studies. Neuropsychological functioning was assessed by formal tests and parent- and teacher-report questionnaires. Data indicated OSA-related cognitive and behavioral impairment that was particularly marked on measures of behavior regulation and some aspects of attention and executive functioning. Minimal effects were observed on measures of intelligence, verbal memory, or processing speed. Exploratory analyses failed to indicate any clear relationship between neuropsychological functioning and objective indexes of hypoxia or sleep disruption, though the sample was small. These data add to a growing literature which suggests that significant neuropsychological deficits are associated with pediatric OSA. Findings suggest a pattern of neuropsychological morbidity that is similar but not identical to that seen in adult OSA. (JINS, 2004,10, 962–975.)
Neuropsychological and neuropathological effects of anoxic or
ischemic induced brain injury
Authors: HOPKINS RAMONA O. , HAALAND KATHLEEN Y.
Published: January 2005

In recent years there has been extensive research in neuropsychological
sequelae of a variety of etiologies, including traumatic brain injury,
dementia, stroke, Parkinson's disease, schizophrenia, and cardiac
surgery. With the exception of stroke and cardiac surgery, significantly
fewer studies have been published regarding neuropsychological outcome in
adults with disorders associated with anoxia or ischemia. Outcomes research
in anoxic or ischemic disorders in pediatric patient populations are even
more limited.
Quality of life, emotional, and cognitive function following acute respiratory distress syndrome
Authors: HOPKINS RAMONA O. , WEAVER LINDELL K. , CHAN KAREN J. , ORME JAMES F.
Published: January 2005

Acute Respiratory Distress Syndrome (ARDS) is characterized by lung injury and hypoxemia, has a high mortality rate, and is associated with significant morbidity including cognitive and emotional sequelae and decreased quality of life. There is limited information regarding which of these factors are associated with decreased quality of life. This study assessed the relationships between quality of life, cognitive and emotional function in ARDS survivors at 1-year post-hospital discharge. Sixty-six ARDS survivors were administered a battery of neuropsychological tests, measures of emotional function and quality of life 1 year post-hospital discharge. At 1 year 45% of the ARDS patients had cognitive sequelae and 29% had mild to moderate symptoms of depression and anxiety. Depression, anxiety, and intensive care unit length of stay were significantly correlated with decreased quality of life. Cognitive impairments did not correlate with decreased quality of life. Illness severity and emotional function, but not cognitive sequelae, are associated with decreased quality of life 1 year following ARDS. ARDS is common and may result in significant cognitive and emotional morbidity and decreased quality of life. (JINS, 2004,10, 1005–1017.)
The Bible of Child/Pediatric Clinical Neuropsychology Has Been
Written
Authors: Butler R.W.
Published: January 2005

The Neuropsychological Evaluation of the Child. Ida Sue Baron.
2004. New York: Oxford University Press. 454 pp., $79.95 (HB).

It is with extreme pleasure that I write a review of this outstanding
text, and also pride that I was selected to be the reviewer. When Dr.
Lezak mailed me the book with a request to write a review for
JINS, I literally called her and thanked her for this
opportunity. I should note, this was not because I would receive a
complimentary copy of The Neuropsychological Evaluation of the
Child, as I had already purchased and read the text, and ordered
an additional copy for my clinic and trainees' access. Dr. Baron
has provided those of us in the field of child/pediatric
neuropsychology with has long been needed: a general background on
clinical issues in conducting neurocognitive assessments with children
and adolescents, along with practical matters and concerns, such as how
to cope with the varying needs of different referral sources, and
providing feedback to parents. Moreover, and most essential, the text
comprehensively reviews neuropsychological measures under all cognitive
domains, and presents exhaustively researched historical and current
normative data for the developmental population. This compilation is an
excellently written book that is comprehensive, detailed, current,
thoughtful, and an invaluable reference for every child and pediatric
neuropsychologist. Indeed, our colleagues who specialize in adult
neuropsychological evaluations would well benefit from reading the text
because the clinical insights are germane to all ages, and the
normative data will enrich their understanding of brain function and
progression throughout the development years.
Mild Cognitive Impairment: Can We Reliably Detect Alzheimer's
Disease Before the Dementia Begins?
Authors: Ostrosky-Solis Feggy
Published: January 2005

Mild Cognitive Impairment Aging to Alzheimer's Disease. R.C.
Petersen (Ed.), 2003, New York: Oxford University Press. 269 pp., $55.00.

People are living longer and along with this phenomenon emerges the
concern about the quality of life as the person ages. While dementia is
by no means a natural consequence of aging, both its incidence and
prevalence increase dramatically with age, from 0.5 percent per year at
the age of 65 years to nearly 8%/year after the age of 85 years
(Evans et al. 1989). Alzheimer's disease (AD) is the most common
cause of dementia. Although the goals of treatment in patients with AD
have been to improve or, at least, to slow the deterioration of memory
and cognition and to maintain independent function, research is moving
from controlling symptoms to early identification and prevention of
age-related cognitive disabilities.
Tropical tropospheric ozone morphology and seasonality seen in satellite and in situ measurements and model calculations
Authors: Kim Jae H. , Na Sunmi , Newchurch M. J. , Martin R. V.
Published: January 2005

An important issue in satellite remote sensing techniques for retrieving tropical tropospheric ozone is understanding the cause of the disagreement between ozone derived from satellite residual‐based methods and the precursor distributions seen in both the fire count distribution and the Measurements Of Pollution In The Troposphere (MOPITT) CO distribution over northern tropical Atlantic and Africa in boreal winter and spring. This discrepancy has been called the Northern Atlantic paradox; however, it actually extends eastward all the way to Indonesia. We define the disagreement as the northern tropical paradox. We employ the scan angle method (SAM) to solve the paradox. This algorithm takes advantage of the difference in the Total Ozone Mapping Spectrometer (TOMS) retrieval information between nadir and high viewing angles. The averaging kernel for this difference exhibits a broad maximum centered at ∼5 km in the troposphere and thereby can be used to estimate tropospheric ozone information. The seasonal distribution of tropospheric ozone derived from the SAM algorithm shows remarkably good agreement with fire counts from Along Track Scanning Radiometer (ATSR), CO from MOPITT, TOMS aerosol index, and ozone distribution from the GEOS‐CHEM model in four seasons over the tropics. In meridional distribution, all of these products clearly reveal the seasonal oscillation between northern tropical Africa in boreal winter and over southern tropical Africa in boreal summer. The residual‐based methods (TOR, CCD, CCP, and modified residual), however, always show the ozone maximum over the southern Atlantic off the coast of southwest Africa. A further comparison with the in situ measurements from the Measurement of Ozone and Water Vapor by Airbus In‐Service Aircraft (MOZAIC) campaign at three locations over the northern tropics, Abidjan (5°N, 4°W), Madras (13°N, 80°E), and Bangkok (14°N, 101°E), supports our results. The seasonality of ozone from the SAM and the model, which shows the ozone maximum in boreal summer and the minimum in boreal winter, is in accordance with the MOZAIC measurements. However, the seasonality of the RBMs does not agree with the seasonality of in situ measurements. We conclude that the northern tropical paradox does not actually exist.
Cosmogenic, radiogenic, and stable isotopic constraints on groundwater residence time in the Nubian Aquifer, Western Desert of Egypt
Authors: Patterson Leslie J. , Sturchio Neil C. , Kennedy B. Mack , van Soest Matthias C. , Sultan Mohamed , Lu Zheng‐Tian , Lehmann Bernhard , Purtschert Roland , El Alfy Zeinhom , El Kaliouby Baher , Dawood Yehia , Abdallah Ali
Published: January 2005

Measurements of radiochlorine (36Cl), radiogenic noble gases (4He and 40Ar), and stable chlorine isotope ratios were obtained to assess the residence time of groundwater in the Nubian Aquifer of the Western Desert of Egypt. Measured 36Cl/Cl ratios yield apparent residence times from ∼0.2 to 1.2 × 106 years in the deep (600–1200 m) groundwater (assuming constant Cl) and ≤0.16 × 106 years in the shallow (<600 m) groundwater. Values of δ37Cl in the groundwater strengthen the application of the 36Cl dating method by constraining Cl sources and identifying groundwater mixing. Dissolved gases were measured in some of the deep groundwater samples. Measured 4He concentrations indicate accumulation of radiogenic 4He that is qualitatively consistent with the age progression indicated by the 36Cl/Cl ratios, but the flux of external 4He from the underlying crust has not been quantified and is not constant throughout the aquifer. Concentrations of 40Ar range from 3.3 to 6.7 × 10−4 ccSTP/g and indicate excess air incorporation at recharge. Measured 40Ar/36Ar ratios do not exceed the atmospheric ratio. A two‐dimensional numerical hydrodynamic transect of the aquifer was modeled from the area of the Uweinat Uplift to the northern Bahariya Oasis. Predicted groundwater velocities in the deep portion of the aquifer are 0.5–3.5 m/yr with groundwater residence times up to 9 × 105 years; residence times up to 1.3 × 106 years are predicted in the confining shale. Aquifer properties are estimated by using the model to fit the measured 36Cl/Cl ratios. Under these conditions, hydrodynamic residence times are within about 30% of those calculated from 36Cl when mixing of Cl− is accounted for in the highest‐Cl− deep groundwaters. By mutually calibrating multiple methods (hydrodynamic, 36Cl, and 4He), a consistent picture of the Nubian Aquifer has emerged in which lateral flow from a southern recharge area dominates the deep horizons, while shallow horizons contain younger, autochthonous recharge.
Salinity change in the subtropical Atlantic: Secular increase and teleconnections to the North Atlantic Oscillation
Authors: Rosenheim Brad E. , Swart Peter K. , Thorrold Simon R. , Eisenhauer Anton , Willenz Philippe
Published: January 2005

Recent studies comparing shipboard data between the 1950's and the 1990's have shown significant, heterogeneous adjustments of the temperature‐salinity structure of the N. Atlantic Ocean. Here, we present proxy records of temperature and salinity from aragonite sclerosponge skeletons, extending existing records of the Salinity Maximum Waters (SMW) of the N. Atlantic back to 1890. These proxy records show secular temperature increases of 1.6–2.0°C, higher than published global averages, and salinity increases of 0.35–0.5 psu, smaller than short‐term secular trends recently measured. Salinity reconstructions vary more significantly on the decadal scale, showing changes that are related to low‐frequency variations of the North Atlantic Oscillation (NAO). On both secular and decadal time scales, the records indicate significant thermohaline changes in the SMW, either via forcing at the surface or increasing depths of density surfaces in the Bahamas.
Global and local isostatic coherence from the wavelet transform
Authors: Kirby J. F. , Swain C. J.
Published: January 2005

A method to compute the variations in lithospheric elastic thickness (Te) has been developed, using the wavelet transform. The technique, which uses a superposition of two‐dimensional Morlet wavelets in a geometry named a ‘fan’ wavelet, is designed to yield isotropic yet complex wavelet coefficients for the co‐ and cross‐spectra of gravity and topography data. These are then used to compute a spatially‐varying, isostatic coherence, from which both global and local estimates may be obtained. We applied the method to synthetic gravity and topography generated for a thin elastic plate of uniform thickness 20 km, yielding an apparent, spatially variable Te of 24.5 ± 3.5 km. The estimated global coherence for this model appears to fit the theoretical prediction as well as Fourier transform‐based estimates, and is smoother than these. We also computed the wavelet coherence, and hence spatially‐varying Te, for a plate of non‐uniform thickness, yielding a difference with the model of −2.0 ± 1.7 km.
Human influence on increasing Arctic river discharges
Authors: Wu Peili , Wood Richard , Stott Peter
Published: January 2005

Climate models predict an intensification of hydrological cycle as anthropogenic greenhouse gas emissions to the atmosphere increase. As part of the process, high latitude precipitation and consequently river runoffs are expected to increase. Some observations have indicated that such a process may have started already during the late half of the 20th century. Arctic river flow changes simulated in HadCM3 with all historical external factors agree with river monitoring data reported by Peterson et al. [2002]. Model simulated total river discharges into the Arctic Ocean have increased by an annual rate of 8.73 km3 since the 1960s. Increasing high latitude precipitation is contributing a substantial part to the upward trend, which is likely to be the early stage of intensifying global hydrological cycle caused by anthropogenic factors, as we do not see the trend in the same model forced with natural factors alone.
Earthquake statistics at Parkfield: 1. Stationarity of b values
Authors: Schorlemmer D. , Wiemer S. , Wyss M.
Published: January 2005

In this paper (paper 1), we quantitatively show that the heterogeneous pattern of b values (of the Gutenberg‐Richter relation) in the Parkfield segment of the San Andreas fault is to a high degree stationary for the past 35 years. This prepares the grounds for paper 2, where we test the hypothesis that our model of spatially varying b values forecasts future seismicity more accurately than the approach in which one assumes a constant b value equal to the average regional value. The method we develop to measure stationarity in the presence of spatial heterogeneity consists of the following steps: (1) Determine the optimal dimensions of the sampling volume by mapping b values with a wide range of radii and selecting the largest radius that gives the most detailed resolution of the b value heterogeneity. Along the selected fault segment, the high data density permits the definition of the dominant dimensions of the seismotectonic fabric, which is about 8–10 km. (2) Map the difference in b value between two periods, selecting numerous possible catalog divisions. (3) Identify significant changes of b values by the Utsu test (Utsu, 1992). Along the studied fault segment of 110 km length, only one patch of radius 5 km showed a significant increase in b, from below average to above, as a function of time. This change in b initiates around 1993 and thus correlates in space and time with a well‐documented episode of creep at depth. Using the derived spatial variable b value distributions, we find that the highest probability for earthquakes with magnitude M ≥ 6 is in the Middle Mountain asperity, where the 1966 Parkfield earthquake nucleated and where all M ≥ 4.5 events in the data set occurred. In contrast, if only the regional average b value of 0.92 is used to predict future seismicity, the creeping segment north of Parkfield should produce major earthquakes most frequently, a conclusion that contradicts the observations.
Influence of pollution on cloud reflectance
Authors: Krüger Olaf , Marks Roman , Graßl Hartmut
Published: January 2005

After the collapse of the East Bloc in 1989, the political and economic changes resulted in significant reductions of industrial activities and thus atmospheric pollution that modified cloud reflectance over and in the lee of the main European emission sources. This impact during a two‐decade transition (1981–1999) of atmospheric pollution in Europe, in particular in East Germany and Poland, was studied on the basis of emission data, measured aerosol concentrations, and satellite observations of cloud reflectance. In these main European emission areas the high degree of air pollution generally enhanced variability of cloud reflectance during the 1980s. The variability was strongest for the early 1980s. A distinct influence of increased particle number density and increased black carbon content as well as secondary aerosol formation is detected. Toward the late 1990s, both the radius effect and the absorption effect, as the two components of the so‐called first indirect aerosol effect, have declined because of reduced particulate matter and sulphur dioxide emissions. The results indicate a pronounced influence of stability on the indirect aerosol effect over Central Europe. The analyzed frequency distributions of cloud reflectance show characteristics that are in line with the theory of radiative transfer.
A new method for multicomponent activity coefficients of electrolytes in aqueous atmospheric aerosols
Authors: Zaveri Rahul A. , Easter Richard C. , Wexler Anthony S.
Published: January 2005

Three‐dimensional models of atmospheric inorganic aerosols need accurate and computationally efficient parameterizations of activity coefficients of various electrolytes in multicomponent aqueous solutions. In this paper, we extend the Taylor's series expansion mixing rule used by C. Wagner in 1952 for estimating activity coefficients in dilute alloy solutions to aqueous electrolyte solutions at any concentration. The resulting method, called the multicomponent Taylor expansion method (MTEM), estimates the mean activity coefficient of an electrolyte in a multicomponent solution on the basis of its values in binary solutions of all the electrolytes present in the mixture at the solution water activity aw, assuming aw is equal to the ambient relative humidity. MTEM is applied here for atmospheric aerosol systems containing H+, NH4+, Na+, Ca2+, SO42−, HSO4−, NO3−, and Cl− ions. The aerosol water content is calculated using the Zdanovskii‐Stokes‐Robinson (ZSR) method. For self‐consistency, most of the MTEM and ZSR parameters are derived using the comprehensive Pitzer‐Simonson‐Clegg model at 298.15 K and are valid for an aw range of 0.2–0.97. Because CaSO4 is sparingly soluble, it is treated as a solid in the model over the entire aw range. MTEM is evaluated for several multicomponent systems representing various continental and marine aerosols and is contrasted against the mixing rule of C. L. Kusik and H. P. Meissner and of L. A. Bromley and the newer approach of S. Metzger and colleagues. Predictions of MTEM are found to be generally within a factor of 0.8–1.25 of the comprehensive Pitzer‐Simonson‐Clegg model and are shown to be significantly more accurate than predictions of the other three methods. MTEM also yields a noniterative solution of the bisulfate ion dissociation in sulfate‐rich systems: a major computational advantage over other ionic‐strength‐based methods that require an iterative solution. CPU time requirements of MTEM relative to other methods for sulfate‐poor and sulfate‐rich systems are also discussed.
Precipitation, sublimation, and snow drift in the Antarctic Peninsula region from a regional atmospheric model
Authors: van Lipzig N. P. M. , King J. C. , Lachlan‐Cope T. A. , van den Broeke M. R.
Published: January 2005

A regional atmospheric model, with a horizontal grid spacing (Δx) of 14 km, is used to study the surface mass balance components (precipitation, sublimation, and snow drift) in the region of the Antarctic Peninsula (AP). An integration is performed for the 7‐year period 1987–1993, using a realistic forcing at the lateral model boundaries and at the sea surface. Output from this integration indicates that the precipitation reaches its maximum value on the northwestern slope of the AP, where the upward motion in the atmosphere is largest. Uplift occurs upstream of the barrier, affecting the precipitation distribution over sea. The effect of the barrier on the precipitation distribution over the Bellingshausen Sea might have important implications for the ocean circulation in this region. The mean precipitation over the grounded ice of the AP (1.20 m water eq yr−1) is 6 times larger than the mean value over all the grounded ice of Antarctica. Our estimates for the surface sublimation and wind transport of snow over the grounding line toward the sea are 9% and 6 ± 1% of the precipitation, respectively. In situ data of the wind distribution at three coastal sites located on the northern, eastern, and western sides of the AP are used to evaluate the modeled wind field, which is important for the snow drift calculations. For two of the three sites considered, the prevailing wind direction and bimodal wind distribution are correctly represented by the model. The calculated distribution of accumulation and ablation due to snow drift shows a complex pattern. The wind removes snow from the spine of the AP, where the near‐surface flow field diverges, whereas deposition occurs mainly on the eastern slopes, where the near‐surface flow field converges. An intercomparison between two 7‐year integrations at different horizontal resolution (Δx = 14 km and Δx = 55 km) shows that the precipitation on the northwestern slope is very sensitive to the model resolution: In the Δx = 14 km integration, precipitation on the northwestern slope is higher than in Δx = 55 km because of higher vertical velocities, resulting in a 35% increase in average precipitation over the grounded ice of the AP.
Evaluation of GOME satellite measurements of tropospheric NO2 and HCHO using regional data from aircraft campaigns in the southeastern United States
Authors: Martin R. V. , Parrish D. D. , Ryerson T. B. , Nicks D. K. , Chance K. , Kurosu T. P. , Jacob D. J. , Sturges E. D. , Fried A. , Wert B. P.
Published: January 2005

We compare tropospheric measurements of nitrogen dioxide (NO2) and formaldehyde (HCHO) from the Global Ozone Monitoring Experiment (GOME) satellite instrument with in situ measurements over eastern Texas and the southeast United States. On average, the GOME and in situ measurements of tropospheric NO2 and HCHO columns are consistent despite pronounced sampling differences. The geometric mean in situ to GOME ratios over the campaign are 1.08 for NO2 and 0.84 for HCHO, with corresponding geometric standard deviations of 1.27 and 1.38. The correlation of the observed column spatial variability between the two NO2 measurement sets is encouraging before (r2 = 0.54, n = 18) and after (r2 = 0.67, n = 18) correcting for a sampling bias. Mean relative vertical profiles of HCHO and NO2 calculated with a global three‐dimensional model (GEOS‐CHEM) and used in the GOME retrieval are highly consistent with in situ measurements; differences would affect the retrieved NO2 and HCHO columns by a few percent. GOME HCHO columns over eastern Texas include contributions from anthropogenic volatile organic compound (VOC) emissions but are dominated by biogenic VOC emissions at the regional scale in August–September when HCHO columns are within 20% of those over the southeastern United States. In situ measurements show that during summer the lowest 1500 m (the lower mixed layer) contains 75% of the tropospheric NO2 column over Houston and Nashville, and 60% of the HCHO column over Houston. Future validation of space‐based measurements of tropospheric NO2 and HCHO columns over polluted regions should include coincident in situ measurements that span the entire satellite footprint, especially in the heterogeneous mixed layer.
Analysis of the evolution of the Antarctic ozone hole size
Authors: Alvarez‐Madrigal M. , Pérez‐Peraza J.
Published: January 2005

The Antarctic ozone hole in the stratospheric layer has two basic parameters: depth and size. In this work the evolution of the ozone hole size (OHS) is analyzed using the monthly mean data for September, October, and November during 1982–2003. On the basis of the analysis of subsets of the data series we found signals of a reversal in the OHS trend during the period 1995–2003 for the months of October and November. On the other hand, the trends of the OHS subsets for the month of September show cyclical changes that approximately follow the variations of the geomagnetic Ap index and the 10.7‐cm solar flux index. The detected beginning of the recovery process is a good test for models in order to match observations.
Titan's stratospheric composition driven by condensation and dynamics
Authors: Hourdin Frédéric , Lebonnois Sébastien , Luz David , Rannou Pascal
Published: January 2005

Atmospheric transport of chemical compounds and organic haze in the stratosphere of Titan is investigated with an axisymmetric general circulation model. It has been shown previously that the meridional circulation, dominated by global Hadley cells, is responsible both for the creation of an intense stratospheric zonal flow and for the accumulation of chemical compounds and haze in high latitudes. The modified composition in turn intensifies the meridional circulation and equator‐to‐pole thermal contrasts. This paper analyzes in detail the transport processes responsible for the observed vertical and latitudinal variations of atmospheric composition. It is shown that the competition between rapid sinking of air from the upper stratosphere in the winter polar vortex and latitudinal mixing by barotropic planetary waves (parameterized in the model) controls the vertical gradient of chemical compounds. The magnitude of polar enrichment (of a factor 1.4 to 20 depending on the particular species) with respect to low latitudes is mostly controlled by the way the meridional advection increases the concentrations of chemical compounds in the clean air which is rising from the troposphere, where most of the chemical compounds are removed by condensation (the temperature at the tropopause being close to 70 K). The agreement between the observed and simulated contrasts provides an indirect but strong validation of the simulated dynamics, thus confirming the explanation put forward for atmospheric superrotation. It is shown also that by measuring the atmospheric composition, the Cassini‐Huygens mission will provide a strong constraint about Titan's atmospheric circulation.
Evolution of large shield volcanoes on Venus
Authors: Herrick Robert R. , Dufek Josef , McGovern Patrick J.
Published: January 2005

We studied the geologic history, topographic expression, and gravity signature of 29 large Venusian shield volcanoes with similar morphologies in Magellan synthetic aperture radar imagery. While they appear similar in imagery, 16 have a domical topographic expression and 13 have a central depression. Typical dimensions for the central depression are 150 km wide and 500 m deep. The central depressions are probably not calderas resulting from collapse of a shallow magma chamber but instead are the result of a corona‐like sagging of a previously domical volcano. The depressions all have some later volcanic filling. All but one of the central depression volcanoes have been postdated by geologic features unrelated to the volcano, while most of the domical volcanoes are at the top of the stratigraphic column. Analysis of the gravity signatures in the spatial and spectral domains shows a strong correlation between the absence of postdating features and the presence of dynamic support by an underlying plume. We infer that the formation of the central depressions occurred as a result of cessation of dynamic support. However, there are some domical volcanoes whose geologic histories and gravity signatures also indicate that they are extinct, so sagging of the central region apparently does not always occur when dynamic support is removed. We suggest that the thickness of the elastic lithosphere may be a factor in determining whether a central depression forms when dynamic support is removed, but the gravity data are of insufficient resolution to test this hypothesis with admittance methods.
Time series analysis of ion dynamics in glassy ionic conductors obtained by a molecular dynamics simulation
Authors: Habasaki J. , Ngai K. L. , Hiwatari Y.
Published: January 2005

We present several characteristics of ionic motion in glassy ionic conductors brought out by time series analysis of molecular dynamics (MD) simulation data. Time series analysis of data obtained by MD simulation can provide crucial information to describe, understand and predict the dynamics in many systems. The data have been treated by the singular spectrum analysis (SSA), which is a method to extract information from noisy short time series and thus provide insight into the unknown or partially unknown dynamics of the underlying system that generated the time series. Phase-space plot reconstructed using the principal components of SSA exhibited complex but clear structures, suggesting the deterministic nature of the dynamics.