Sex education - a responsibility of the secondary school

Thesis (Ed.M.)--Boston University This item was digitized by the Internet Archive

Flexstab on the IBM 360

FLEXSTAB, an array of computer programs developed on CDC equipment, has been converted to operate on the IBM 360 computation system. Instructions for installing, validating, and operating FLEXSTAB on the IBM 360 are included. Hardware requirements are itemized and supplemental materials describe JCL sequences, the CDC to IBM conversion, the input output subprograms, and the interprogram data flow

Clouds, photolysis and regional tropospheric ozone budgets.

We use a three-dimensional chemical transport model to examine the shortwave radiative effects of clouds on the tropospheric ozone budget. In addition to looking at changes in global concentrations as previous studies have done, we examine changes in ozone chemical production and loss caused by clouds and how these vary in different parts of the troposphere. On a global scale, we find that clouds have a modest effect on ozone chemistry, but on a regional scale their role is much more significant, with the size of the response dependent on the region. The largest averaged changes in chemical budgets (±10–14%) are found in the marine troposphere, where cloud optical depths are high. We demonstrate that cloud effects are small on average in the middle troposphere because this is a transition region between reduction and enhancement in photolysis rates. We show that increases in boundary layer ozone due to clouds are driven by large-scale changes in downward ozone transport from higher in the troposphere rather than by decreases in in-situ ozone chemical loss rates. Increases in upper tropospheric ozone are caused by higher production rates due to backscattering of radiation and consequent increases in photolysis rates, mainly J(NO2). The global radiative effect of clouds on isoprene, through decreases of OH in the lower troposphere, is stronger than on ozone. Tropospheric isoprene lifetime increases by 7% when taking clouds into account. We compare the importance of clouds in contributing to uncertainties in the global ozone budget with the role of other radiatively-important factors. The budget is most sensitive to the overhead ozone column, while surface albedo and clouds have smaller effects. However, uncertainty in representing the spatial distribution of clouds may lead to a large sensitivity of the ozone budget components on regional scales

Interannual variability of tropospheric composition:the influence of changes in emissions, meteorology and clouds

We have run a chemistry transport model (CTM) to systematically examine the drivers of interannual variability of tropospheric composition during 1996-2000. This period was characterised by anomalous meteorological conditions associated with the strong El Nino of 1997-1998 and intense wildfires, which produced a large amount of pollution. On a global scale, changing meteorology (winds, temperatures, humidity and clouds) is found to be the most important factor driving interannual variability of NO2 and ozone on the timescales considered. Changes in stratosphere-troposphere exchange, which are largely driven by meteorological variability, are found to play a particularly important role in driving ozone changes. The strong influence of emissions on NO2 and ozone interannual variability is largely confined to areas where intense biomass burning events occur. For CO, interannual variability is almost solely driven by emission changes, while for OH meteorology dominates, with the radiative influence of clouds being a very strong contributor. Through a simple attribution analysis for 1996-2000 we conclude that changing cloudiness drives 25% of the interannual variability of OH over Europe by affecting shortwave radiation. Over Indonesia this figure is as high as 71%. Changes in cloudiness contribute a small but non-negligible amount (up to 6%) to the interannual variability of ozone over Europe and Indonesia. This suggests that future assessments of trends in tropospheric oxidizing capacity should account for interannual variability in cloudiness, a factor neglected in many previous studies

Re International Association of Machinists, Lodge 717, and Orenda Ltd

Employee Grievance alleging failure by the company to provide weekly indemnity for non-occupational sickness. The facts: On June 19, 1968, Mr. Garden, the grievor, went to Orenda\u27s plant doctor for an examination. He was referred to his family doctor. That same day, and again on June 24th, he consulted Dr. W.K. Taylor who had been his doctor for some years. On June 25th, Dr. Taylor signed an Attending Physician\u27s Statement for submission to the company in support of a claim by the grievor for weekly indemnity for non-occupational sickness. The statement noted under the heading diagnosis the following: neurodermatitis both hands, duodenal ulcer symptoms . It is also noted on the statement that the patient has been totally disabled (unable to work) from June 19, 1968, and that he should be able to return to work on July 2, 1968. Under the heading how long will the patient be partially disabled? the answer given is for the same period

Impact of climate change on tropospheric ozone and its global budgets

International audienceWe present the chemistry-climate model UMCAM in which a relatively detailed tropospheric chemical module has been incorporated into the UK Met Office's Unified Model version 4.5. We obtain good agreements between the modelled ozone/nitrogen species and a range of observations including surface ozone measurements, ozone sonde data, and some aircraft campaigns. Four 2100 calculations assess model responses to projected changes of anthropogenic emissions (SRES A2), climate change (due to doubling CO2), and idealised climate change-associated changes in biogenic emissions (i.e. 50% increase of isoprene emission and doubling emissions of soil-NOx). The global tropospheric ozone burden increases significantly for all the 2100 A2 simulations, with the largest response caused by the increase of anthropogenic emissions. Climate change has diverse impacts on O3 and its budgets through changes in circulation and meteorological variables. Increased water vapour causes a substantial ozone reduction especially in the tropical lower troposphere (>10 ppbv reduction over the tropical ocean). On the other hand, an enhanced stratosphere-troposphere exchange of ozone, which increases by 80% due to doubling CO2, contributes to ozone increases in the extratropical free troposphere which subsequently propagate to the surface. Projected higher temperatures favour ozone chemical production and PAN decomposition which lead to high surface ozone levels in certain regions. Enhanced convection transports ozone precursors more rapidly out of the boundary layer resulting in an increase of ozone production in the free troposphere. Lightning-produced NOx increases by about 22% in the doubled CO2 climate and contributes to ozone production. The response to the increase of isoprene emissions shows that the change of ozone is largely determined by background NOx levels: high NOx environment increases ozone production; isoprene emitting regions with low NOx levels see local ozone decreases, and increase of ozone levels in the remote region due to the influence of PAN chemistry. The calculated ozone changes in response to a 50% increase of isoprene emissions are in the range of between ?8 ppbv to 6 ppbv. Doubling soil-NOx emissions will increase tropospheric ozone considerably, with up to 5 ppbv in source regions

Winter Conditions Influence Biological Responses of Migrating Hummingbirds

Conserving biological diversity given ongoing environmental changes requires the knowledge of how organisms respond biologically to these changes; however, we rarely have this information. This data deficiency can be addressed with coordinated monitoring programs that provide field data across temporal and spatial scales and with process-based models, which provide a method for predicting how species, in particular migrating species that face different conditions across their range, will respond to climate change. We evaluate whether environmental conditions in the wintering grounds of broad-tailed hummingbirds influence physiological and behavioral attributes of their migration. To quantify winter ground conditions, we used operative temperature as a proxy for physiological constraint, and precipitation and the normalized difference vegetation index (NDVI) as surrogates of resource availability. We measured four biological response variables: molt stage, timing of arrival at stopover sites, body mass, and fat. Consistent with our predictions, we found that birds migrating north were in earlier stages of molt and arrived at stopover sites later when NDVI was low. These results indicate that wintering conditions impact the timing and condition of birds as they migrate north. In addition, our results suggest that biologically informed environmental surrogates provide a valuable tool for predicting how climate variability across years influences the animal populations

Ozone Response to Aircraft Emissions: Sensitivity Studies with Two-dimensional Models

Our first intercomparison/assessment of the effects of a proposed high-speed civil transport (HSCT) fleet on the stratosphere is presented. These model calculations should be considered more as sensitivity studies, primarily designed to serve the following purposes: (1) to allow for intercomparison of model predictions; (2) to focus on the range of fleet operations and engine specifications giving minimal environmental impact; and (3) to provide the basis for future assessment studies. The basic scenarios were chosen to be as realistic as possible, using the information available on anticipated developments in technology. They are not to be interpreted as a commitment or goal for environmental acceptability

Seasonal and inter-annual variations in Troposphere-to-Stratosphere Transport from the Tropical Tropopause Layer

International audienceIn an earlier study of troposphere-to-stratosphere transport (TST) via the tropical tropopause layer (TTL), we found that the vast majority of air parcels undergoing TST from the base of the TTL enter the extratropical lowermost stratosphere quasi-horizontally and show little or no regional preference with regards to origin in the TTL or entry into the stratosphere. We have since repeated the trajectory calculations - originally limited to a single northern hemisphere winter period - in a variety of months and years to assess how robust our earlier findings are to change of timing. To first order, we find that the main conclusions hold, irrespective of the season, year and phase of the El Niño Southern Oscillation (ENSO). We also explore: the distribution of TST between the northern and southern hemispheres; the sensitivity of modelled TST to the definition of the tropopause; and the routes by which air parcels undergo transport exclusively to the stratospheric overworld. Subject to a dynamical definition of the tropopause, we identify a strong bias towards TST in the southern hemisphere, particularly during the northern hemisphere summer. The main difference on switching to the World Meteorological Organization's thermal tropopause definition is that much less TST is modelled in the subtropics and, relative to the dynamical definition, we calculate significantly less transport into the extratropical lowermost stratosphere (ELS) ? an important region with regards to ozone chemistry. In contrast to the rather homogeneous nature of TST into the ELS, we find that transport to the overworld takes place from relatively well-defined regions of the TTL, predominantly above the West Pacific and Indonesia, except for an El Niño period in which most transport takes place from regions above the East Pacific and South America