CISM

SOHO image animation (57k)
images from SOHO-EIT

Observations Underlying and Validating Models
interplanetary particles and fields

In-situ measurements of particles and fields upstream of the Earth provide the ultimate basis for testing the success of solar-observation-based space weather models. The extent to which the models agree with observations of solar wind stream structure, transients, and energetic particle populations, determines whether we can make accurate forecasts from 27 days (one solar rotation) to several days ahead.

The top image is of WIND spacecraft data, including the Berkeley 3-D plasma experiment solar wind parameters and the Goddard Space Flight Center interplanetary magnetic field components. This approximately 2-day long time series includes the 10 January 1997 magnetic cloud transient associated with the halo CME observed on SOHO on 6 January. The lower image is of the ACE Real Time Solar Wind data for a recent three-day period, and includes a computed Dst geomagnetic index estimate based on these measurements. Both of these data sets, as well as the ISEE-3 and IMP-8 archived data, provide the ultimate test for the space weather prediction potential of our solar-based models. While spacecraft measurements upstream of Earth will always provide the most accurate space weather forecasts, the longer range predictions (from 27-day solar rotation, to several-day storm warning scales) can only be made on a regular basis using solar observations and models.

Click on the images to the left to enlarge.

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