{"id":18976,"date":"2020-07-15T21:21:01","date_gmt":"2020-07-16T01:21:01","guid":{"rendered":"http:\/\/www.cr2.cl\/eng\/?p=18976"},"modified":"2020-07-30T21:25:21","modified_gmt":"2020-07-31T01:25:21","slug":"rare-peek-at-patagonia-in-winter-nasa-earth-observatory","status":"publish","type":"post","link":"https:\/\/www.cr2.cl\/eng\/rare-peek-at-patagonia-in-winter-nasa-earth-observatory\/","title":{"rendered":"Rare Peek at Patagonia in Winter (Nasa Earth Observatory)"},"content":{"rendered":"

In southern South America, clouds often rule the skies. But in June 2020, just the right weather patterns were in place to provide a rare, clear view of Patagonia in winter.<\/p>\n

On June 26, when the Moderate Resolution Imaging Spectroradiometer<\/a> (MODIS) on NASA\u2019s Aqua<\/a> satellite acquired these images, skies were clear over nearly all of Patagonia, which spans more than 1 million square kilometers of the continent\u2019s southern end. Snow cover is visible from the western slopes of the Andes Mountains in Chile to the coastal lowlands in Argentina.<\/p>\n

According to Ren\u00e9 Garreaud, a professor at the University of Chile, it\u2019s unusual to see such a widespread cloud-free area over Patagonia. \u201cThe last time that I saw a completely clear image was in February 2019<\/a>,\u201d he said. At that time, during the Southern Hemisphere\u2019s summer, the warm seasonal temperatures meant snow and ice were mostly limited to the spine of the Andes and the Patagonian icefields.<\/p>\n

The region is typically cloudy in satellite imagery<\/a> due to the year-round passage of storms. The southern tip of the continent dips into a belt of prevailing westerly winds, along which high- and low-pressure systems constantly drift eastward. The terrain also enhances the region\u2019s cloudiness: when winds encounter the Andes, moist air blowing in from the Pacific Ocean is forced upward, where it cools and condenses into clouds.<\/p>\n

In June, the usual weather pattern came to a halt. A system of high pressure settled in over the Drake Passage\u2014the waterway just south of the continent\u2014and brought clear skies to the wider region. The weather system stayed put for nearly a week. The phenomenon is known as a \u201cblocking high,\u201d aptly named because it blocks the typical movement of air masses. In this case, westerly winds were forced to take a detour.<\/p>\n

As a result of the blocking high, unusually cold temperatures stretched from Patagonia all the way to Paraguay and Bolivia. Cloud-free skies mean that heat near the land surface can more easily escape to space, resulting in cooler temperatures. In addition, the diverted westerly winds brought cold air from Antarctica and funneled it right into southern Patagonia.<\/p>\n

\n
\"\"<\/div>\n
\n

June 26, 2020<\/p>\n

Those cold temperatures kept the Patagonian plateau in Argentina blanketed under snow that fell during a major storm on June 23-24. Parts of the southern Andes receive abundant precipitation each year, measuring more than 500 centimeters (200 inches). It\u2019s less common, however, to see snowfall so far east on an arid part of the continent that receives less than 30 centimeters (12 inches) of precipitation each year.<\/div>\n<\/div>\n<\/div>\n

The bout of frigid air, however, was not enough to freeze the deep lakes east of the icefield (detailed image). \u201cEven in winter, surface air temperatures are generally above 0 degrees C.,\u201d Garreaud said. \u201cSo the cold event was intense, but not long enough to freeze these lakes.\u201d Left unfrozen, the lakes\u2019 turquoise color\u2014a result of \u201cglacial flour<\/a>\u201d\u2014contrasts even more with the surrounding white snow.<\/p>\n

NASA Earth Observatory images by Lauren Dauphin, using MODIS data from NASA EOSDIS\/LANCE and GIBS\/Worldview<\/a>. Story by Kathryn Hansen<\/a>.<\/i><\/p>\n

Read at Nasa Earth Observatory<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"

In southern South America, clouds often rule the skies. But in June 2020, just the right weather patterns were in place to provide a rare, clear view of Patagonia in winter. On June 26, when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA\u2019s Aqua satellite acquired these images, skies were clear over nearly all of […]<\/p>\n","protected":false},"author":3,"featured_media":18977,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[25,13],"tags":[32,111,999,1000,1001],"_links":{"self":[{"href":"https:\/\/www.cr2.cl\/eng\/wp-json\/wp\/v2\/posts\/18976"}],"collection":[{"href":"https:\/\/www.cr2.cl\/eng\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.cr2.cl\/eng\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.cr2.cl\/eng\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.cr2.cl\/eng\/wp-json\/wp\/v2\/comments?post=18976"}],"version-history":[{"count":1,"href":"https:\/\/www.cr2.cl\/eng\/wp-json\/wp\/v2\/posts\/18976\/revisions"}],"predecessor-version":[{"id":18978,"href":"https:\/\/www.cr2.cl\/eng\/wp-json\/wp\/v2\/posts\/18976\/revisions\/18978"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.cr2.cl\/eng\/wp-json\/wp\/v2\/media\/18977"}],"wp:attachment":[{"href":"https:\/\/www.cr2.cl\/eng\/wp-json\/wp\/v2\/media?parent=18976"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.cr2.cl\/eng\/wp-json\/wp\/v2\/categories?post=18976"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.cr2.cl\/eng\/wp-json\/wp\/v2\/tags?post=18976"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}