Plasma heating, plasma flow and wave production around an electron beam injected into the ionosphere

A brief historical summary of the Minnesota ECHO series and other relevant electron beam experiments is given. The primary purpose of the ECHO experiments is the use of conjugate echoes as probes of the magnetosphere, but beam-plasma and wave studies were also made. The measurement of quasi-dc electric fields and ion streaming during the ECHO 6 experiment has given a pattern for the plasma flow in the hot plasma region extending to 60m radius about the ECHO 6 electron beam. The sheath and potential well caused by ion orbits is discussed with the aid of a model which fits the observations. ELF wave production in the plasma sheath around the beam is briefly discussed. The new ECHO 7 mission to be launched from the Poker Flat range in November 1987 is described

Modulation and heliocentric gradient of low energy cosmic rays near solar minimum, 1965

Modulation and heliocentric gradient of low energy cosmic rays near solar minimum, 196

Magnetospheric substorm effects on energetic electrons in the outer Van Allen belt /Summary of technical report CR-137/

Substorm-associated acceleration effects on electron increases in post-midnight sector of outer radiation bel

A survey of the total radiation in space observed by the OGO satellites, 5 September 1964 - 27 May 1968

Graphical and tabular summaries of ionization rates in space recorded by OGO spacecraft ion chamber

Local and nonlocal biogeophysical effects of deforestation in a climate model

Land cover change (LCC) influences surface temperature locally via biogeophysical effects by changing the water, energy, and momentum budget. In addition to these locally induced changes (local effects), LCC at a given location can cause changes in temperature elsewhere via advection and changes in circulation (nonlocal effects). This dissertation presents an approach to separate local and nonlocal effects in climate models. In three studies, the local and nonlocal effects on surface temperature are analyzed separately. First, local and nonlocal effects are separated in the land-atmosphere model ECHAM6/JSBACH3 by simulating LCC in some model grid cells while leaving vege- tation unchanged in others. The results show that the local effects do not depend on the number of LCC grid cells used in the separation approach. The local effects on surface temperature in the model agree reasonably well with observations. An energy balance decomposition reveals that the mechanisms differ strongly between the local and nonlocal effects. In the second part, a new look-up approach is developed to investigate the local effects on historical LCC and LCC in future scenarios. Historically, biogeophysical changes in surface temperature are dominated by land use while in the future, the combina- tion of warming background climate and subsequent natural shifts in the geographical distribution of forests may become of equal importance. The third part focuses on the nonlocal effects. Simulations with the fully coupled cli- mate model MPI-ESM reveal that the nonlocal cooling of large-scale LCC substantially contributes to the discrepancy between modeled and observed biogeophysical changes in surface temperature. When globally averaged, the deforestation-induced cooling from nonlocal effects outweighs the warming from local effects, and both local and nonlocal effects largely scale linearly with the spatial extent of LCC. The globally av- eraged nonlocal effects induce a cooling for deforestation in all latitudinal bands. In an inter-model comparison of plausible deforestation scenarios, the nonlocal effects induce a cooling also for most other investigated models. This thesis bridges the gap between idealized studies on large-scale LCC and studies on more plausible LCC extents. Furthermore, the separate analysis of local and nonlocal effects reconciles previous model-based studies that found a negative radiative forcing from deforestation and a global mean cooling, and observation-based studies that found a deforestation-induced local warming in most regions

Präventive Tiergesundheitskonzepte in der ökologischen Milchviehhaltung

Ziel war es, mittels einer Fragebogenerhebung (n=1000), Untersuchungen in Praxisbetrieben (n=50) sowie einer Expertenbefragung den Status quo der Tiergesundheitssituation in der ökologischen Milchviehhaltung zu erfassen, mögliche Beziehungen zu Haltungsbedingungen und vorbeugenden Maßnahmen zu untersuchen sowie Entwicklungsperspektiven für Tiergesundheitskonzepte aufzuzeigen. In den repräsentativ ausgewählten Untersuchungsbetrieben betrug die durchschnittliche Behandlungsinzidenz für Mastitis 33 % (0-101 %). Bei der Einzelbetrachtung von vorbeugenden Maßnahmen (Zitzendesinfektion etc.) konnte in der überwiegenden Zahl der Fälle kein positiver Effekt auf die Mastitisinzidenz festgestellt werden; das Vorhandensein einer Anrüstautomatik zeigte dabei die deutlichsten Effekte. Diese Ergebnisse sind jedoch mit Vorbehalt zu betrachten, da aufgrund der geringen Stichprobengröße keine multivariate Analyse erfolgen konnte. Die mittlere Lahmheitsprävalenz betrug 18% (2–53 %). In Boxenlaufställen gehaltene Herden wiesen signifikant höhere Prävalenzen (20 %, 4-53 %) auf als Herden in Laufställen mit freier eingestreuter Liegefläche (10 %, 2-19 %; p<0.01, Mann-Whitney-U). Zudem bestanden Zusammenhänge mit Mängeln in der Haltungsumwelt wie unzureichende Verformbarkeit des Liegeuntergrunds. Die Häufigkeit von Stoffwechselstörungen zeigte ein hohes Maß an Variabilität zwischen Betrieben. Die Gebärpareseinzidenz bewegte sich zwischen 0 und 25 % (MW 5,9 %), während klinische Ketosen (0–12 %), Azidosen (0–11 %) und Labmagenverlagerungen (0–2 %) deutlich seltener auftraten. Die Ergebnisse der vorliegenden Untersuchung zeigen, dass Produktionskrankheiten wie Mastitis, Lahmheiten und Stoffwechselstörungen in der ökologischen Milchviehhaltung eine wichtige Rolle spielen. In der Expertenbefragung wurde besonders der Bedarf nach verstärktem Wissenstransfer in die Praxis herausgestellt

Status quo der Tiergesundheitssituation in der ökologischen Milchviehhaltung – Mastitis, Lahmheiten, Stoffwechselstörungen

It was the aim of the present study to assess the health state in German organic dairy farming with regard to mastitis, lameness and metabolic disorders, to investigate possible relationships with the specific housing conditions and/or the use of preventive measures, and to point out chances for further development. The project consisted of a questionnaire study (1.000 farms) and on-farm investigations in a representative sub-sample of 50 farms. In each farm, herd health records from 2001 and 2002 were copied and subsequently evaluated with regard to mastitis and metabolic disorders. Lameness prevalence was recorded using a 5-point locomotion scoring system during the farm visit. Mastitis incidence ranged between 1 and 101 % (mean 33,4 %). The average lameness prevalence was 17,6 % (2 – 53 %) with herds housed in cubicles showing significantly more lameness (19,7 %, 4 – 53 %) than herds on straw yard systems (10,0 %, 2 – 19 %; p<0.01, Mann-Whitney-U). Housing and management factors such as comfort of the lying place had further significant effects on lameness prevalence. The incidence of metabolic disorders showed a high level of variation. Milk fever incidence ranged between 0 and 25 % (mean 5,9 %). Treatments of clinical ketosis (0 – 12 %), acidosis (0 – 11 %) and displacement of the abomasum (0 – 2 %) were less frequent and seemed to be only of relevance on single farms. The present study demonstrates that production diseases such as mastitis, lameness and metabolic disorders play a considerable role in German organic dairy farming

Experimental verification of drift shell splitting in the distorted magnetosphere

OGO-3 and ATS-1 data used in experimental verification of drift shell splitting in distorted magnetospher

Description of data plots from the University of Minnesota ion chamber and electron spectrometer on OGO-1 and OGO-3

Data plots obtained from ion chamber and electron spectrometer experiments aboard OGO A and OGO C satellite

Why does the locally induced temperature response to land cover change differ across scenarios

Land cover change (LCC) affects temperature locally. The underlying biogeophysical effects are influenced not only by land use (location and extent) but also by natural biogeographic shifts and background climate. We examine the contributions of these three factors to surface temperature changes upon LCC and compare them across Coupled Model Intercomparison Project phase 5 (CMIP5) scenarios. To this end, we perform global deforestation simulations with an Earth system model to deduce locally induced changes in surface temperature for historical and projected forest cover changes. We find that the dominant factors differ between historical and future scenarios: the local temperature response is historically dominated by the factor land use change, but the two other factors become just as important in scenarios of future land use and climate. An additional factor contributing to differences across scenarios is the dependence on the extent of forests before LCC happens: For most locations, the temperature response is strongest when starting deforestation from low forest cover fractions