{"id":1545,"date":"2014-12-12T15:25:00","date_gmt":"2014-12-12T20:25:00","guid":{"rendered":"http:\/\/site.extension.uga.edu\/climate\/?p=1545"},"modified":"2014-12-12T20:47:27","modified_gmt":"2014-12-13T01:47:27","slug":"standardized-precip-graphs-show-persistence-of-wet-and-dry-spells","status":"publish","type":"post","link":"https:\/\/site.extension.uga.edu\/climate\/2014\/12\/standardized-precip-graphs-show-persistence-of-wet-and-dry-spells\/","title":{"rendered":"Standardized precip graphs show persistence of wet and dry spells"},"content":{"rendered":"

A new tool from the University of Arizona Climate Science Applications Program displays standardized precipitation index (SPI)values for a range of time scales over time.\u00a0 SPI is a calculated rainfall amount that takes into account the average rainfall and the standard deviation of rainfall over time and puts it in a standard format which can be easily compared between regions with different average precipitation conditions.\u00a0 On the graph, green indicates a precipitation surplus and yellow indicates a precipitation deficit.\u00a0 The higher up on the graph, the longer the time scale of the SPI value.\u00a0 Time moves from 1985 on the left to the present on the right.<\/p>\n

The description of this tool is located here<\/a> and an example of how to read the plot is below for AZ.<\/p>\n

\"Source:<\/a>
Source: University of AZ CALS<\/figcaption><\/figure>\n

For the Southeast, the graph shows that recent years at many time scales have been dominated by dry conditions (not a big surprise considering that we have had three major droughts in the last 15 years).\u00a0 The 1998-2002 drought had the lowest SPI values at longer time scales (large black circle) while the 2007-2009 drought had its lowest SPI values at more intermediate time scales, indicating a drought that came on faster but moderated more quickly.\u00a0 The wet spell in late fall 2009 (thin black oval) was very short and did not really affect the longer-term dry conditions at all.<\/p>\n

\"standardized<\/a><\/p>\n

You can get similar charts for individual states at https:\/\/cals.arizona.edu\/climate\/misc\/spi\/spi_contour_states.html<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

A new tool from the University of Arizona Climate Science Applications Program displays standardized precipitation index (SPI)values for a range of time scales over time.\u00a0 SPI is a calculated rainfall amount that takes into account the average rainfall and the standard deviation of rainfall over time and puts it in a standard format which can […]<\/p>\n","protected":false},"author":58,"featured_media":1547,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8],"tags":[],"class_list":["post-1545","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-tools-for-climate-and-agriculture"],"_links":{"self":[{"href":"https:\/\/site.extension.uga.edu\/climate\/wp-json\/wp\/v2\/posts\/1545","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/site.extension.uga.edu\/climate\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/site.extension.uga.edu\/climate\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/site.extension.uga.edu\/climate\/wp-json\/wp\/v2\/users\/58"}],"replies":[{"embeddable":true,"href":"https:\/\/site.extension.uga.edu\/climate\/wp-json\/wp\/v2\/comments?post=1545"}],"version-history":[{"count":2,"href":"https:\/\/site.extension.uga.edu\/climate\/wp-json\/wp\/v2\/posts\/1545\/revisions"}],"predecessor-version":[{"id":1549,"href":"https:\/\/site.extension.uga.edu\/climate\/wp-json\/wp\/v2\/posts\/1545\/revisions\/1549"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/site.extension.uga.edu\/climate\/wp-json\/wp\/v2\/media\/1547"}],"wp:attachment":[{"href":"https:\/\/site.extension.uga.edu\/climate\/wp-json\/wp\/v2\/media?parent=1545"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/site.extension.uga.edu\/climate\/wp-json\/wp\/v2\/categories?post=1545"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/site.extension.uga.edu\/climate\/wp-json\/wp\/v2\/tags?post=1545"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}