Planning the Future Space Weather Operations and Research Infrastructure Proceedings of a Workshop (2021) / Chapter Skim
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6 Strategic Knowledge and Observation Gaps
6 Strategic Knowledge and Observation Gaps
Pages 46-60
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From page 46... ...
SUN/HELIOSPHERE GAPS The Sun is the ultimate driver of much of Earth's space weather environment, through its effects on Earth's surface and atmosphere at its lower boundary, to the variable solar wind particles and fields that both form the magnetosphere and control the planets' exposure to galactic and solar cosmic rays (see Figure 6.1)
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From page 47... ...
, and in roughly 30-45 minutes in cases where the incident solar wind plasma and field conditions are of interest. These conditions are often used in models -- some of which are L1 data-driven -- for a wide range of geospace consequences ranging from energetic particle exposure of Earth-orbiting spacecraft and the ISS, to forecasting the expected strengths of the magnetospheric ring current and auroral electrojets, and their related upper atmosphere and ionosphere perturbations.
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From page 48... ...
Solar energetic particles (SEPs) , also referred to as solar cosmic rays, generally precede and accompany ICMEs, with their fluxes sometimes the highest upon arrival of the ICME shock.
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From page 49... ...
The recent weak sunspot cycles have been accompanied by some on-average weaker solar wind parameters, including the interplanetary field magnitude and solar wind density. These, together with the related weaker solar EUV fluxes, have changed the average conditions in geospace, resulting in generally weaker geomagnetic storms and consequences.
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From page 50... ...
The Sun's polar magnetic fields also figure prominently in the boundary conditions for coronal and solar wind modeling used in forecasting. Presently they are reconstructed using synoptic ground-based or space-based magnetograms, stitched together to form a map of the global solar magnetic field.
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From page 51... ...
In situ instruments would measure the solar wind plasma and field properties that would be experienced at L1 in several days provided that the coronal structures controlling the ecliptic solar wind streams maintain their configuration over that time span -- a situation often realized during undisturbed times. The desirable instruments for an L5 mission are mostly the same as those for L1 missions, including EUV imagers and coronagraphs, plus in situ instruments (solar wind plasma, magnetic field, and energetic particles)
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From page 52... ...
As mentioned above, because of the nature of the solar wind interaction with Earth's nearly dipolar global field, a large southward component of the interplanetary field literally opens the magnetospheric shield external driving and other influences. Thus an ICME which carries large southward Bz can cause major consequences compared to the same ICME with a flipped Bz polarity.
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From page 53... ...
Table 6.1 provides a summary of workshop presentations and discussions regarding solar and heliospheric knowledge gaps, and options to those fill gaps. GEOSPACE GAPS The "Strategic Knowledge and Observations -- Geospace" session was organized in a manner similar to the "Sun/Heliopshere Gaps" session summarized above.
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From page 54... ...
as well as spacecraft design require measurements over disparate timescales, distinguishing between space weather for spaceflight operational decisions and space climatology for space mission design considerations. A concern of some participants is how radiation belt and ring current energy populations will be monitored going forward now that the NASA Van Allen Probes mission (2012–2019)
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From page 55... ...
spacecraft. In addition, low-energy plasmaspheric electrons, ~eV energy, play a critical role in determining the inner edge of outer zone radiation belt electrons and an important boundary for spacecraft surface charging.
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From page 56... ...
Energetic particles enhance ionospheric conductance at high latitudes and modify electrical M-I currents. Solar wind driven convection imposes electric fields that drive currents in the lower ionosphere setting ionospheric plasma into motion at higher altitudes, with ions escaping into geospace and beyond.
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From page 57... ...
The global Birkeland current measurement provides a stringent validation check of the operational MHD models used to derive space weather predictions of LEO and ground impacts. The global, continuous nature of the Iridium sampling via AMPERE complements ground magnetometer observations as a validation check of the operational MHD models used to derive space weather predictions of LEO and ground impacts.
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From page 58... ...
Relevant to filling these knowledge gaps and needs are plans that include NASA's implementation of the Geospace Dynamics Constellation;12 NSF's support for the SWARM-EX CubeSat mission,13 an initial three-satellite pathfinder towards a larger constellation of 6 to 12 CubeSats, each with a more elaborate suite of instruments; and ESA's Daedalus mission,14 a concept that is based on a mother satellite, which carries a suite of instruments along with four small satellites carrying a subset of instruments that are released into the atmosphere. It was also noted that space traffic management, which requires improved models of the neutral atmosphere, will become a shared DoD-NOAA responsibility as space commerce increases dramatically in the current decade (Figure 6.5)
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From page 59... ...
STRATEGIC KNOWLEDGE AND OBSERVATION GAPS 59 FIGURE 6.5 Space is getting crowded. NOTE: Not all will be at 1,325 km; around 7,500 will fly at the very low Earth orbit (335-346 km)
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From page 60... ...
Global ionospheric convection SuperDARN coherent radar network. Global B-field aligned current systems Iridium satellite constellation for global phone/data communications carry magnetometers, may provide real-time currents (AMPERE)
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