Supergranule variability in Mt. Wilson Ca II K images [presentation]
Hock, R., Eparvier, F. G., Mcintosh, S., & Rast, M. P. (2010). Supergranule variability in Mt. Wilson Ca II K images [presentation]. In 216th American Astronomical Society Meeting. American Astronomical Society: Miami, FL, US.
We examined the Mt. Wilson Ca II K archive to quantify the long-term changes in the average size of supergranules over five solar cycles from 1930 to 1985. We determined that, although the Mt. Wilson Ca II K images are limited by atmospheric seeing, there is sufficient contrast in the images to i... Show moreWe examined the Mt. Wilson Ca II K archive to quantify the long-term changes in the average size of supergranules over five solar cycles from 1930 to 1985. We determined that, although the Mt. Wilson Ca II K images are limited by atmospheric seeing, there is sufficient contrast in the images to identify supergranules. In general, we found that supergranule size increases during the rising phase of a solar cycle, reaching a peak at solar maximum. In the declining phase of a solar cycle, supergranule size has a larger second peak, becoming out of phase with the solar cycle for several years. Show less
