{"id":128,"date":"2014-08-25T12:25:10","date_gmt":"2014-08-25T10:25:10","guid":{"rendered":"https:\/\/site.uit.no\/spaceweather\/?p=128"},"modified":"2014-08-25T12:25:10","modified_gmt":"2014-08-25T10:25:10","slug":"solar-event-and-its-effect-on-the-ground-in-scandinavia","status":"publish","type":"post","link":"https:\/\/site.uit.no\/spaceweather\/2014\/08\/25\/solar-event-and-its-effect-on-the-ground-in-scandinavia\/","title":{"rendered":"Solar event and its effect on the ground in Scandinavia"},"content":{"rendered":"

Yesterday (24. August) there was an X-ray event on the sun. Such events ionize the dayside ionosphere above “normal” levels and may cause blackouts. Here is the Alert issued by SWPC:<\/p>\n

Space Weather Message Code: SUMXM5<\/em>
\nSerial Number: 119<\/em>
\nIssue Time: 2014 Aug 24 1256 UTC<\/em><\/p>\n

SUMMARY: X-ray Event exceeded M5<\/em>
\nBegin Time: 2014 Aug 24 1200 UTC<\/em>
\nMaximum Time: 2014 Aug 24 1217 UTC<\/em>
\nEnd Time: 2014 Aug 24 1225 UTC<\/em>
\nX-ray Class: M5.9<\/em>
\nOptical Class: 2b<\/em>
\nLocation: S07E77<\/em>
\nNOAA Scale: R2 – Moderate<\/em><\/p>\n

Comment: Impulsive M5\/2b flare from new Region 2151 near the SE limb. Type II (593 km\/s) and Tenflare (409 sfu) radio emissions associated with this event.<\/em>
\nPotential Impacts: Area of impact centered primarily on sub-solar point on the sunlit side of Earth.<\/em>
\nRadio – Limited blackout of HF (high frequency) radio communication for tens of minutes.<\/em><\/p>\n

And indeed effects were seen on the ground. Here are the raw riometer data from Skibotn and Ny-\u00c5lesund. A riometer measures the power of the background cosmic radiation. When the ionosphere increase in density at its lowest altitudes this radiation is absorbed and absorption is observed in the curve. I will at a later point write a post about the excellent instrument of riometers.<\/p>\n

\"Skibotn<\/a>
Skibotn riometer raw data plot<\/figcaption><\/figure>\n
\"Ny-\u00c5lesund<\/a>
Ny-\u00c5lesund riometer raw data plot<\/figcaption><\/figure>\n

Notice at 12 UT there is a small dip in the curves lasting for a little less than half an hour. That is the effect of the x-ray event and indicates some absorption of HF signals at 30 and 40 MHz. Now, both Skibotn and Ny-\u00c5lesund are at hight latitudes, if one moved closer to the sub-solar point one would probably see even more absorption.<\/p>\n

The event was also seen to affect geomagnetic conditions a little at most latitudes of the TGO magnetometer network, see the simultanous dip in the curves at 12 UT in the stackplot<\/a>.<\/p>\n

Nothing dramatic about this space weather event, but it illustrates quite nicely one of the ways the Sun may affect conditions here on Earth<\/p>\n","protected":false},"excerpt":{"rendered":"

Yesterday (24. August) there was an X-ray event on the sun. Such events ionize the dayside ionosphere above “normal” levels and may cause blackouts. Here is the Alert issued by SWPC: Space Weather Message Code: SUMXM5 Serial Number: 119 Issue Time: 2014 Aug 24 1256 UTC SUMMARY: X-ray Event exceeded …<\/p>\n","protected":false},"author":430,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-128","post","type-post","status-publish","format-standard","hentry","category-uncategorized","column","threecol"],"_links":{"self":[{"href":"https:\/\/site.uit.no\/spaceweather\/wp-json\/wp\/v2\/posts\/128","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/site.uit.no\/spaceweather\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/site.uit.no\/spaceweather\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/site.uit.no\/spaceweather\/wp-json\/wp\/v2\/users\/430"}],"replies":[{"embeddable":true,"href":"https:\/\/site.uit.no\/spaceweather\/wp-json\/wp\/v2\/comments?post=128"}],"version-history":[{"count":1,"href":"https:\/\/site.uit.no\/spaceweather\/wp-json\/wp\/v2\/posts\/128\/revisions"}],"predecessor-version":[{"id":131,"href":"https:\/\/site.uit.no\/spaceweather\/wp-json\/wp\/v2\/posts\/128\/revisions\/131"}],"wp:attachment":[{"href":"https:\/\/site.uit.no\/spaceweather\/wp-json\/wp\/v2\/media?parent=128"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/site.uit.no\/spaceweather\/wp-json\/wp\/v2\/categories?post=128"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/site.uit.no\/spaceweather\/wp-json\/wp\/v2\/tags?post=128"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}