INTRODUCING THE THERMOSPHERE CLIMATE INDEX: There's a new data feed on Spaceweather.com--the daily Thermosphere Climate Index (TCI). This is a number recently developed by NASA and university researchers that tells us how Earth's upper atmosphere is responding to solar activity. Monitoring TCI is a must for anyone wanting a true situational awareness of how space weather "touches" Earth. Visit Spaceweather.com for the full story.
Above: Although TCI was only recently invented, researchers have figured out how to calculate its value going back to the 1940s. Today's edition of Spaceweather.com explains where we stand in the historical record.
