723 research outputs found
Effects of solar wind density on auroral electrojets and brightness under influence of substorms
Using the auroral electrojet indices and Polar Ultraviolet Imager auroral images, we examined two fortuitous events during which the solar wind density had clear enhancements while the other solar wind parameters were relatively constant. Two electrojet enhancements were found in each event. The first electrojet enhancement was likely to be related to a substorm in which an auroral bulge appeared at premidnight. The second electrojet enhancement was driven by the density enhancement in the solar wind. The auroral oval became wider in latitude and the auroral distribution became dispersed after the density enhancement arrived at the Earth. The total auroral power integrated over the entire nightside region from 50 to 80° MLAT, however, did not increase significantly in response to the density enhancement. Our interpretation is that the substorm that occurred prior to the solar wind density enhancement had drained out a significant portion of the stored energy in the magnetotail; therefore, less precipitation energy was deposited into the auroral ionosphere by the density enhancement
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Sleepwalking into lock-in? Avoiding wrongs to future people in the governance of solar radiation management research
This paper argues for two ways in which we can avoid the reckless endangerment of future people in the governance of solar radiation management (SRM) research, which could happen through lock-in to SRM deployment from research. SRM research is at an early stage, one at which the mechanisms of lock-in could start to operate. However, lock-in fit to endanger future people could be slowed or stopped through targeted governance. This paper argues that governance of SRM research that does not include provisions to detect, slow, or stop lock-in fails the test of an intergenerationally adequate precautionary principle, and that research governed without these provisions cannot itself be justified as a precaution against the impacts of climate change
Pine Needle Abortion in Cattle: A Progress Report
Cow and calf loss due to pine needle abortion (PNA) in cattle grazing foothill ranges having stands of ponderosa pine (Pinus ponderosa) continues to cause managerial, as well as economic problems, for many ranchers in South Dakota, Colorado, Idaho and California as well as many areas in Canada
Radio Astronomy
Contains research objectives and summary of research on seven research projects and a report on one research project.Joint Services Electronics Program (Contract DAAB07-75-C-1346)National Science Foundation (Grant AST73-05042-AO2)National Institutes of Health (Grant 5 SO5 RR07047-10)U. S. Air Force - Electronic Systems Division (Contract F19628-75-C-0122)M.I.T. Sloan Fund for Basic ResearchNational Aeronautics and Space Administration (Contract NAS5-21980)National Aeronautics and Space Administration (Contract NAS5-22485
Radio Astronomy
Contains research objectives and summary of research on five research projects and reports on two research projects.Joint Services Electronics Program (Contract DAAB07-74-C-0630)National Science Foundation (Grant GP-40484X)National Science Foundation (Grant MPS73-05042-A01)National Institutes of Health (Grant 1 RO1 GM20370-02)National Aeronautics and Space Administration (Contract NAS1-10693)National Aeronautics and Space Administration (Contract NAS5-21980)National Aeronautics and Space Administration (Contract NAS5-20091)U.S. Air Force - Electronic Systems Division (Contract F19628-73-C-0196
Climate change and the duties of the disadvantaged: reply to Caney
Discussions of where the costs of climate change adaptation and mitigation should fall often focus on the ‘polluter pays principle’ or the ‘ability to pay principle’. Simon Caney has recently defended a ‘hybrid view’, which includes versions of both of these principles. This article argues that Caney’s view succeeds in overcoming several shortfalls of both principles, but is nevertheless subject to three important objections: first, it does not distinguish between those emissions which are hard to avoid and those which are easy to avoid; second, its only partial reference to all-things-considered justice means it cannot provide a full account even of climate justice; and third, it assigns to the poor very limited duties to meet climate change costs, even where they have created those costs, which may incentivise them to increase emissions. An alternative pluralistic account which avoids these objections is presented
Pressure balance at the magnetopause: Experimental studies
The pressure balance at the magnetopause is formed by magnetic field and
plasma in the magnetosheath, on one side, and inside the magnetosphere, on the
other side. In the approach of dipole earth's magnetic field configuration and
gas-dynamics solar wind flowing around the magnetosphere, the pressure balance
predicts that the magnetopause distance R depends on solar wind dynamic
pressure Pd as a power low R ~ Pd^alpha, where the exponent alpha=-1/6. In the
real magnetosphere the magnetic filed is contributed by additional sources:
Chapman-Ferraro current system, field-aligned currents, tail current, and
storm-time ring current. Net contribution of those sources depends on
particular magnetospheric region and varies with solar wind conditions and
geomagnetic activity. As a result, the parameters of pressure balance,
including power index alpha, depend on both the local position at the
magnetopause and geomagnetic activity. In addition, the pressure balance can be
affected by a non-linear transfer of the solar wind energy to the
magnetosheath, especially for quasi-radial regime of the subsolar bow shock
formation proper for the interplanetary magnetic field vector aligned with the
solar wind plasma flow.Comment: 8 pages, 2 figure
Extreme geomagnetic disturbances due to shocks within CMEs
We report on features of solar wind-magnetosphere coupling elicited by shocks propagating through coronal mass ejections (CMEs) by analyzing the intense geomagnetic storm of 6 August 1998. During this event, the dynamic pressure enhancement at the shock combined with a simultaneous increase in the southward component of the magnetic field resulted in a large earthward retreat of Earth\u27s magnetopause, which remained close to geosynchronous orbit for more than 4 h. This occurred despite the fact that both shock and CME were weak and relatively slow. Another similar example of a weak shock inside a slow CME resulting in an intense geomagnetic storm is the 30 September 2012 event, which strongly depleted the outer radiation belt. We discuss the potential of shocks inside CMEs to cause large geomagnetic effects at Earth, including magnetopause shadowing
Allocating the Burdens of Climate Action: Consumption-Based Carbon Accounting and the Polluter-Pays Principle
Action must be taken to combat climate change. Yet, how the costs of climate action should be allocated among states remains a question. One popular answer—the polluter-pays principle (PPP)—stipulates that those responsible for causing the problem should pay to address it. While intuitively plausible, the PPP has been subjected to withering criticism in recent years. It is timely, following the Paris Agreement, to develop a new version: one that does not focus on historical production-based emissions but rather allocates climate burdens in proportion to each state’s annual consumption-based emissions. This change in carbon accounting results in a fairer and more environmentally effective principle for distributing climate duties
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