The National Space Weather Program - Establishing metrics for the ionosphere and thermosphere

Abstract

The National Space Weather Program (NSWP) has an overarching goal “to achieve an active, synergistic, interagency system to provide timely, accurate, and reliable space weather warnings, observations, specifications, and forecasts within the next 10 years.” Among the critical elements contributing to a successful NSWP is the need to establish metrics against which quantitative goals can be defined and progress can be measured. As space physics makes the transition from purely, curiositydriven science to one with significant practical applications, it must provide quantitative and objective measures of its capabilities. We expect that this testing will accelerate scientific progress. The highest priority ionosphere thermosphere science parameters, against which metrics should be defined, are electron density, neutral mass density, and the amplitude of electron density irregularities. These same parameters are also the most critical parameters for application users, affecting communications, navigation, and satellite orbit prediction. Metrics can be established on the parameters themselves, or on “features,” such as the magnitude and location of the equatorial ionization anomaly or subamoral trough. Having identified suitable metrics we are able to determine where we are now in our prediction capabilities, and establish where we would like to he in ten years. Release A: “Copyright 1998 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.” I.ntroductiQg Our reliance on technological systems continues to increase dramatically, and many of these systems are susceptible to extreme space weather conditions. Improved specification and forecasts of the space environment could mitigate, or possibly eliminate, the risk of technological failure. The National Space Weather Program (NSWP) is a far reaching initiative to transition the knowledge from the research community to operational use to provide forecasts and specification of the space environment. The strategy relies on support from four pillars: research, observations, models, and education. The NSWP is comprehensive, covering physical processes from the solar surface, through the solar wind and magnetosphere, to the Earth’s upper atmosphere. Many of the effects relevant to the operation systems although driven by the sun and solar wind, occur in the near-Earth environment of the magnetosphere, ionosphere and thermosphere. For example, satellite systems are vulnerable to magnetospheric particle populations causing deep dielectric and surface charging, and spurious electronic spacecraft commands. Power systems are susceptible to geomagnetically induced currents. Navigation and communication are affected by changes in ionospheric density, total electron content, and irregularities. Sudden injection of energy into the upper atmosphere during geomagnetic storms changes neutral density and satellite drag, resulting in the loss of tracking of many lowEarth orbiting space objects. American Institute of Aeronautics and Astronautics (c)l999 American Institute of Aeronautics & Astronautics The means by which expertise from the research community can be made available to operations is by transitioning state-of-the-art models. These models have evolved over the years and capture the new understanding of the sun-Earth physical system. One of the keys to the success of the NSWP is the creation of a method to incorporate research results into operational models quickly and efficiently. At the core of this process is the Rapid Prototyping Center @PC). Figure 1, which is an updated rendition of an earlier figure from the NSWP Implementation Plan, illustrates the process of running, testing, evaluating, modifying research-grade models. RPCs are under development at the Space Environment Center (SEC) under direction of T. Onsager and at the Air Force Research Laboratory under direction of G. Ginet. RPCs are designed to test the value and feasibility of a research model for operational use. It is designed to provide immediate feedback to model developers in a quasi-operational environment, and allow competing technologies to be examined quickly, cheaply, and effectively. Graduates of the RPC will be implemented in the operational centers at NOAA’s SEC and the AF Space Weather Squadron (55” SWXS), representing the civilian and DOD applications communities, respectively. The second critical element contributing to a successful NSWP is the need to establish metrics against which quantitative goals can be defined and progress can be measured. This represents an important addition to traditional approaches to science. The research expertise and understanding need to be quantified in terms of the accuracy or skill of predicting processes on the Sun, in the interplanetary medium, and in the Earth’s magnetosphere, ionosphere, and thermosphere. With these metrics we can evaluate where are we today, and determine where we want, or need to be, in 10 years.