{"id":375,"date":"2006-11-26T19:07:54","date_gmt":"2006-11-27T00:07:54","guid":{"rendered":"\/?p=375"},"modified":"2012-01-15T16:11:52","modified_gmt":"2012-01-15T21:11:52","slug":"the-sky-is-falling","status":"publish","type":"post","link":"https:\/\/www.realclimate.org\/index.php\/archives\/2006\/11\/the-sky-is-falling\/","title":{"rendered":"The sky IS falling Le ciel nous tombe vraiment sur la t\u00eate<\/lang_fr>"},"content":{"rendered":"
\n

<\/a>
\nA timely perspective article in Science<\/em> this week addresses the issues of upper atmosphere change. ‘Upper’ atmosphere here is the stratosphere up to the ionosphere (~20 to 300 km). La\u0161tovi\u010dka et al<\/a> point out that cooling trends are exactly as predicted by increasing greenhouse gas trends, and that the increase in density that this implies is causing various ionspheric layers to ‘fall’. This was highlighted a few years back by Jarvis et al (1998)<\/a> and in New Scientist<\/a> in 1999 (and I apologise for stealing their headline!). <\/p>\n

The changes in the figure are related to the cooling seen in the lower stratospheric MSU-4 records (UAH<\/a> or RSS<\/a>), but the changes there (~ 15-20 km) are predominantly due to ozone depletion. The higher up one goes, the more important the CO2<\/sub> related cooling is. It’s interesting to note that significant solar forcing would have exactly the opposite effect (it would cause a warming) – yet another reason to doubt that solar forcing is a significant factor in recent decades.<\/p>\n

Update:<\/strong> The best explanation for the cooling trends can be found on ESPERE<\/a> (alternative site<\/a>), in particular, figure 3<\/a> (alt. version<\/a>).<\/p>\n


\nTraduit par Etienne Pesnelle<\/small>
\n<\/a>Dans le num\u00e9ro de cette semaine de Science, un article opportun de mise en perspective traite des probl\u00e8mes du changement de l’atmosph\u00e8re sup\u00e9rieure. Ladite atmosph\u00e8re “sup\u00e9rieure” consiste en la stratosph\u00e8re jusqu’\u00e0 l’ionosph\u00e8re (~20 \u00e0 300 km). La\u0161tovicka et al<\/a> soulignent que la tendance au refroidissement est exactement telle que pr\u00e9dite par la tendance \u00e0 la hausse des gaz \u00e0 effet de serre, et que l’accroissement de densit\u00e9 que cela implique est en train de provoquer la “chute” de diff\u00e9rentes couches de la ionosph\u00e8re. Cela a \u00e9t\u00e9 mis en exergue il y a quelques ann\u00e9es par Jarvis et al.<\/a> (1998) et dans New Scientist<\/a> en 1999 (et je m’excuse de leur avoir vol\u00e9 le titre de leur article!).<\/p>\n

Les changements dans le graphique sont li\u00e9s au refroidissement constat\u00e9 dans les enregistrements MSU-4 de la basse stratosph\u00e8re (que ce soit ceux provenant des bases de donn\u00e9es UAH<\/a> ou RSS<\/a>), mais les changements \u00e0 ces altitudes (~ 15-20 km) sont principalement d\u00fbs \u00e0 la rar\u00e9faction de l’ozone. Plus on monte, plus le refroidissement d\u00fb au CO2<\/sub> est important. Il est int\u00e9ressant de noter qu’un for\u00e7age solaire significatif aurait exactement l’effet inverse (il provoquerait un r\u00e9chauffement) – encore une autre raison de douter que le for\u00e7age solaire est un facteur significatif [du r\u00e9chauffement climatique] des derni\u00e8res d\u00e9cennies.<\/p>\n

Mise \u00e0 jour<\/strong> : la meilleure explication des tendances au refroidissement peut \u00eatre trouv\u00e9e sur ESPERE<\/a>, en particulier la figure 3<\/a>.<\/lang_fr><\/p>\n\n<\/div> ","protected":false},"excerpt":{"rendered":"

A timely perspective article in Science this week addresses the issues of upper atmosphere change. ‘Upper’ atmosphere here is the stratosphere up to the ionosphere (~20 to 300 km). La\u0161tovi\u010dka et al point out that cooling trends are exactly as predicted by increasing greenhouse gas trends, and that the increase in density that this implies […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","footnotes":""},"categories":[1,3,26],"tags":[],"class_list":["post-375","post","type-post","status-publish","format-standard","category-climate-science","category-greenhouse-gases","category-rc-forum","entry"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t