The Sun to the Earth – and Beyond Panel Reports (2003) / Chapter Skim
Currently Skimming:
4 Report of the Panel on Theory, Modeling, and Data Exploration
4 Report of the Panel on Theory, Modeling, and Data Exploration
Pages 183-210
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 183... ...
SUMMARY 1 85 4.1 INTRODUCTION 188 Sir 4.2 THEORY, COMPUTATION,AND SUCCESS STORIES 189 Key Issues for the Next Decade 190 4.3 THE ROLE OF DATA EXPLORATION 191 Accompl ishments of the Past Decade 1 92 Problems and Solutions 1 92 Avai I abl e Resou rces 1 93 4.4 A COHERENT FRAMEWORK FOR THEORY, MODELING, AND DATA EXPLORATION 200 Coupling Complexity in Space Plasma Systems 200 The Challenges of Coupling Complexity 202 183
|
From page 185... ...
To embrace the demands imposed by hierarchical coupling or coupling complexity nonlinearity and multiscale, multiprocess, multiregional feedback in space physics space physicists must address a number of challenges: · Formulation of sophisticated models that incorporate disparate scales, processes, and regions and the development of analytic theory; · Computation; · Incorporation of coupling complexity into computational models; · Integration of theory, modeling, and space- and ground-based observations; · Data exploration and assimilation; and · Transition of scientific models to operational status in, for example, space weather activities. Recommendation 1.
|
From page 186... ...
This research program would emphasize the development of coupled global models and the synergistic i nvestigati on of we l l -chosen, d isti nct theoretical problems that underlie the basic physics inherent in the fully general self-consistent space physics problem. For major advances to be made in understanding coupling complexity in space physics, sophisticated computational tools, fundamental theoretical analysis, and state-of-theart data analysis must all be brought under a single umbrella program.
|
From page 187... ...
For models to be an effective bridge between space physics theory and economic, societal, and governmental needs, they have to address the demands imposed by coupling complexity and be sufficiently robust, validated, documented, standardized, and supported. These additional demands impose significant challenges to the groups that develop models, and the criteria for transitioning a model successfully to operational use are frequently very different
|
From page 188... ...
Despite the many solar, heliospheric, and geospace models that can potentially be used for operational space weather forecasting, relatively few have so far been transitioned into operation at the NOAA and Air Force space weather centers. This is due to inadequate resources to support transition efforts, in particular at the NOAA Space Environment Center.
|
From page 189... ...
A precise definition of coupling complexity is given in Section 4.4, "A Coherent Framework for Theory, Modeling, and Data Exploration." From this synthesis flows a set of four major recommendations designed to achieve four goals: (1) dramatically improve and expand space physics theory and modeling by embracing the idea of coupling complexity (or, equivalently, nonlinearity and multiscale and multiprocess feedback)
|
From page 190... ...
Finally, the panel observes that class 3 modeling forms the centerpiece of operational space weather forecasting. Currently, only a few models are THE SUN TO THE EARTH AND BEYOND: PANEL REPORTS used, but if meteorology is any indication, the number of models and their scope will increase dramatically in the next decade.
|
From page 191... ...
Solar and space physics observations also represent a national resource of immediate practical value to the United States. Both NOAA and the DOD currently use real-time observations of the Sun, the solar wind, Earth's magnetosphere, and Earth's ionosphere to predict the disruptive effects of space weather on ionospheric communication, aircraft navigation, radar defense, geosynch ronous satel I ite safety, and commercial electrical power supply.
|
From page 192... ...
NOAA NGDC www.ngdc.noaa.gov DOD NGDC www.ngdc.noaa.gov DOE LANE Leadbelly.lanl.gov USGS NGDC www.ngdc.noaa.gov NOTE: NSSDC, National Space Science Data Center; NCAR, National Center for Atmospheric Research; UMD, University of Maryland; NSO, National Solar Observatory; NGDC, National Geophysical Data Center; LANE, Los Alamos National Laboratory. THE SUN TO THE EARTH AND BEYOND: PANEL REPORTS A number of Web sites appeared during the past decade that allow remote researchers to interactively plot and even analyze high-resolution observations from individual experiments.
|
From page 193... ...
As this program is heavily oversubscribed, it has not had a significant impact on theory, modeling, and data exploration. By contrast, NASA's AISRP specifical Iy targets the space sciences and is responsible for many of the success stories discussed in Boxes 4.1 to 4.10.
|
From page 194... ...
2001. Global simulation of magnetospheric space weather effects of the Bastille Day storm.Solar Physics 204: 325-338.
|
From page 195... ...
1 999. Interaction of the solar wind with the local interstellar medium: A theoretical perspective.
|
From page 196... ...
The prevailing empirical diffusion models gave energization rates that were orders of magnitude too slow, and they only described the intensification of existing zones of MeV particles rather than the formation of new stable belts. Advances in theory identified a new process involving fast resonant acceleration by inductive electric fields accompanying a rapid compression of the geomagnetic field.This theory emphasized the need for new approaches to predicting Earth's dynamic radiation belts and to space weather forecasting.
|
From page 197... ...
Concurrent with the development of instruments and observing methods, a significant theoretical effort occurred to develop the complex analysis techniques required to find inversion methods with suitable resolution and precision, to enhance the resolution and physical complexity of the models of the structure and dynamics of the Sun and of its features, and to include wave phase information in the inferences. Finally, the necessity of analyzing many orders of magnitude more data than had hitherto been required has brought about major advances in the handling of data, and these have to some extent propagated throughout the field of solar physics.
|
From page 198... ...
. During the day, upper atmospheric winds produce dynamo electric fields that cause plasma on these geomagnetic field lines to drift upward, which leads to an elevated ionosphere with peak densities of 1 o6 cm-3 and peak altitudes as high as 600 km.
|
From page 199... ...
-100 - 1 50 `1` -200 0 -250 100 1 0 ~ z FIGURE 4.7.1 SOURCE: Plot by R.W. McGuire, Space Physics Data Facility at NASA Goddard Space Flight Center.
|
From page 200... ...
By contrast, a particular plasma region can admit multiple ion and atom populations, each governed by distinct plasma physical processes yet coupled to one another dynamically and self-consistently. An excellent example is the coupling of the solar wind to the local interstellar medium through the intermediary of neutral interstellar atoms (beyond some 10 to 15 AU, the dominant constituent of the heliosphere, by mass, is neutral interstellar H)
|
From page 201... ...
Finally, space plasmas, as illustrated in extraordinary detail by images of the Sun obtained by the spacecraft TRACE, can change their (magnetic field) configuration on extremely short time scales, with an accompanying explosive relaxation in the associated plasma.
|
From page 202... ...
As suggested early in this section, the notion of "coupling complexity" refers to a class of problems or systems that encompass significantly different scales, regions, or particle populations, the understanding of which requires more than one set of defining equations or concepts. As discussed above, for example, the heliosphere contains cosmic rays, the solar wind, neutral atoms, and pickup ions, each of which interacts with the others and requires its own set of equations and coupling terms.
|
From page 203... ...
The first is to further develop existing codes and algorithms, such as three-dimensional MHD codes that incorporate adaptive mesh refinement for example, three-dimensional hybrid codes with improved electron/ ion mass ratios or improved codes for data exploration. These problems do not demand the inclusion of new physics to handle coupling complexity but demand instead substantial progress in current research areas.
|
From page 204... ...
To simply enhance the existing SECTP is infeasible since the Coupling Complexity Initiative (1) is aimed primarily at systems throughout the heliosphere rather than isolated physical processes and does not emphasize the Sun-Earth connection; (2)
|
From page 205... ...
... Examples of high-priority space science themes that are associated with coupling complexity are numerous and embrace many of the most significant challenges in space physics.The following have been identified as excellent examples of coupling complexity in that they are fundamental to the further development of space physics, they cut across the different areas addressed by the five panels of the Solar and Space Physics Survey Committee, and they have the potential to influence both astrophysics and laboratory plasma physics.The examples below all span three or more of the four classes that introduced the notion of coupling complexity (see p.
|
From page 206... ...
Cross-agency programs have proved successful in the past. The panel recommends the formation of a cross-agency commission, with NASA possibly taking the lead though its LWS program, to examine the implementation of a crossagency Coupling Complexity Initiative.
|
From page 207... ...
This is particularly true of LWS data analysis funds. Challenge 5: Data Exploration and Assimilation Government-supported ground- and space-based research projects are currently returning an unparalleled wealth of in situ and remote space physics observations.
|
From page 208... ...
A similar management structure, tasked with similar functions, was proposed at the Space Physics Data System Commun ity Workshop held at Rice University in 19938 and has subsequently been endorsed at community forums and review teams. Table 4.2 provides the suggested funding profile for an SPIS.
|
From page 209... ...
Challenge 6:Transition of Scientific Models to Operational Status Despite the existence of many solar, heliospheric, and geospace models that can potentially be used for operational space weather forecasting, relatively few have so far been transitioned into operation at the NOAA and Air Force space weather centers. This is due to inadequate resources for transition efforts, in particular at the NOAA/Space Environment Center.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.