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Depletion of column ozone in the arctic during the winters of 1993-94 and 1994-95

The total ozone reduction in the Arctic during the winters of 1993/94 acid 1994/95 has been evaluated using the ground-based total ozone measurements of five SAOZ spectrometers distributed in the Arctic and from number density profiles of a balloon-borne version of the instrument. The ozone change resulting from transport has been removed using a 3D Chemistry Transport Model (CTM) run without chem

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Assessments of the possible future climate change, driven by anthropogenic emissions of greenhouse gases, are made with global climate models. These describe the large-scale features rather than regional details of climate, such as variations due to mountains, lakes, and inland oceans. Regional climate modelling improves the details in climate projections. Examples for the Nordic region illustrate

Trajectory studies of polar stratospheric cloud lidar observations at Sodankyla (Finland) during SESAME : Comparison with box model results of particle evolution

Polar stratospheric clouds (PSC) were observed with the multi-wavelength lidar of the MOANA project (Modelling and Observations of Aerosols in the Northern Atmosphere) during SESAME (Second European Stratospheric Arctic and Mid-latitude Experiment). The physical state, liquid or solid, of the cloud particles can be inferred from the lidar data. Using isentropic back-trajectories to obtain the ther

In situ measurements of stratospheric ozone depletion rates in the Arctic winter 1991/1992 : A Lagrangian approach

A Lagrangian approach has been used to assess the degree of chemically induced ozone loss in the Arctic lower stratosphere in winter 1991/1992. Trajectory calculations are used to identify air parcels probed by two ozonesondes at different points along the trajectories. A statistical analysis of the measured differences in ozone mixing ratio and the time the air parcel spent in sunlight between th

Imagining Europe: Framing European Integration in the Lithuanian National Newspapers 1992-2004

This explorative thesis observes how European integration was framed in Lithuanian mass media in the years leading to the accession to the European Union, using it as a case study in the Central Eastern European region entering the EU in 2004. It is situated in the context of the emergence of the concept of European identity in the 1970s expressing the need for European Union countries to develop

Environmental and Geographic Conditions on the Breeding Grounds Drive Bergmannian Clines in Nightjars

Aim: To evaluate (1) whether three migratory nightjar species (Family Caprimulgidae) adhere to Bergmann's rule, (2) whether environmental factors on the breeding or wintering grounds determine body size, and (3) which mechanistic hypotheses best explain Bergmannian patterns in body size. Location: North and South America; Europe and Africa. Taxon: Eastern whip-poor-will (Antrostomus vociferus), Co

Temporal development of ozone within the Arctic Vortex during the winter of 1991/92

In this study we address the question of temporal ozone trends on isentropic surfaces within the Arctic polar vortex during EASOE. We have combined ozone sonde data from twelve campaign stations distributed throughout the European sector of the Arctic. The development of ozone at the 425, 475, 550 and 700K levels is presented, using analysed fields of isentropic potential vorticity and isentropic

Experimental Evolution of the Thermal Performance Curve

The thermal performance curve (TPC) of an organism captures how population growth depends on temperature. When populations experience increased temperatures, such as during global climate change, one prediction is that their TPC can evolve to accommodate the new environmental temperature. Although studies on TPC evolution have mostly focused on modifications in population growth rates, TPC evoluti

Optimisation and Application of Nanoelectroporation for Clonal β-Cell Transfection

Within the field of cell biology, an essential tool is to deliver molecules to cells to manipulate cell behaviour and function. This enables the study of, for example, how a specific change in a cellular process contributes to a disease state. However, cells have barriers, such as the cell membrane, that need to be overcome for the molecules to have an effect. Current transfection methods, such asWithin the field of cell biology, an essential tool is to deliver molecules to cells to manipulate cell behaviour and function. This enables the study of, for example, how a specific change in a cellular process contributes to a disease state. However, cells have barriers, such as the cell membrane, that need to be overcome for the molecules to have an effect. Current transfection methods, such as

Stratospheric ozone depletion and solar UV radiation in the arctic and its potential impact on human health in Finland

A Finnish national climate research programme, SILMU, has funded three projects in the field of ozone and UV radiation research during 1990-1995. The results of these projects are summarised here. The study of temperature sounding records made in Finland 1958-94 has revealed a warming trend in the lower and middle troposphere (up to 0.3 K/decade) and a cooling of similar order of magnitude in the

Yearly cycle of lower tropospheric ozone at the Arctic Circle

Measurements of tropospheric ozone at three sites at the Arctic Circle in the Finnish Lapland are presented. The variability of ground-level ozone over the diurnal and seasonal cycles in 1992-93 is discussed for the sites of Oulanka and Pallas. The variability with height and over the annual cycle in 1989-94 is discussed for the Sodankyla aerological Observatory, which has the longest record on th

Wake analysis of a robotic avian wing with moult gaps in gliding flight

Birds periodically replace their flight feathers through moulting, a process needed to restore aerodynamic function that temporarily reduces the wing surface and flight performance. To mitigate these effects, birds adjust their wings, the angle of attack, and undergo mass loss to compensate for altered aerodynamics.Studying the aerodynamic impact of moult gaps in live birds is challenging, so we u

Dehydration and sedimentation of ice particles in the Arctic stratospheric vortex

Balloon borne frost-point hygrometers and backscatter sondes were launched at Sodankylä, Finland in January and February of 1996. These instruments measure water vapor and the backscatter ratio of light due to polar stratospheric clouds in the Arctic stratospheric vortex. Here we report the results of a hygrometer sonde and a backscatter sonde launched within 3.5 hours of each other on January 22/

Prolonged stratospheric ozone loss in the 1995-96 arctic winter

It is well established that extensive depletion of ozone, initiated by heterogenous reactions on polar stratospheric clouds (PSCs) can occur in both the Arctic and Antarctic lower stratosphere. Moreover, it has been shown that ozone loss rates in the Arctic region in recent years reached values comparable to those over the Antarctic. But until now the accumulated ozone losses over the Arctic have

Lidar observation of spherical particles in a -65°cold cirrus observed above Sodankyla (Finland) during S.E.S.A.M.E.

The absence of LIDAR depolarization in a polar cirrus observed above Sodankyla (Finland) showed the presence of spherical particles at -65°C. The presence of pure liquid water is excluded, since homogeneous freezing should occur at or above -40°C. The cirrus layer was detected at the tropopause, during the horizontal and vertical advection above northern Scandinavia of warm and wet oceanic air. Tw

Observational evidence for chemical ozone depletion over the Arctic in winter 1991-92

LONG-TERM depletion of ozone has been observed since the early 1980s in the Antarctic polar vortex, and more recently at mid-latitudes in both hemispheres, with most of the ozone loss occurring in the lower stratosphere1. Insufficient measurements of ozone exist, however, to determine decadal trends in ozone concentration in the Arctic winter. Several studies of ozone concentrations in the Arctic

Prostate Cancer Foundation White Paper on Combination Therapy for Metastatic Hormone-Sensitive Prostate Cancer

Despite several randomized controlled trials demonstrating the benefits of combination therapies for metastatic hormone-sensitive prostate cancer (mHSPC), a significant treatment gap persists. This initiative by the Prostate Cancer Foundation (PCF) convened stakeholders from academia, community practices, industry, and patient advocacy groups to address critical challenges in mHSPC care. Expert di

Kinetically limited growth of dendritic tin oxide thin films : a machine learning study beyond the structure zone diagram

Even after fifty years since its introduction, the empirical Thornton’s structure zone diagram remains a valuable tool for predicting thin film microstructure. This diagram is essential for understanding the correlation between synthesis, composition, structure, and physical properties in emerging applications. In this work, we critically appraise this diagram by examining Sn─O thin films grown at

Securitizing Science: A Careful Consideration of Trade-offs is Needed

Amid growing geopolitical tensions and the shift toward a multipolar world, research security has emerged as a critical concern for academic institutions and national governments. While efforts to protect science from foreign interference and intellectual property theft are increasing, many current measures lack empirical grounding, clear objectives, or proven effectiveness. This paper discusses t

The perception of walking on an urban forest path in daylight and under electric lighting

In daylight, urban forests promote human health and well-being by offering opportunities for recreation and psychological restoration. In urban forests, electric lighting is often installed to enable recreation during the dark season. This study explored how urban residents experience walking in an urban forest in daylight compared to walking in darkness with electric lighting. Local residents par