{"id":263622,"date":"2023-06-24T15:30:44","date_gmt":"2023-06-24T13:30:44","guid":{"rendered":"https:\/\/climatescience.press\/?p=263622"},"modified":"2023-06-24T15:30:47","modified_gmt":"2023-06-24T13:30:47","slug":"in-search-of-the-greenhouse-signal-in-the-1990s-and-when-did-they-know-2","status":"publish","type":"post","link":"https:\/\/climatescience.press\/?p=263622","title":{"rendered":"In Search of the \u201cGreenhouse Signal\u201d in the 1990s (and when did they know?)"},"content":{"rendered":"\n
\"\"<\/figure>\n\n\n\n

<\/p>\n\n\n\n

From Master<\/strong>Resource<\/a><\/p>\n\n\n\n

By Robert Bradley Jr.<\/em><\/p>\n\n\n\n

\u201cAs for using proxy data to detect a man-made greenhouse effect, I don\u2019t think we\u2019re ever going to get to the point where we\u2019re going to be totally convincing.\u201d \u2013 Thomas Wigley, National Center for Atmospheric Research, (April 28, 1998)<\/p>\n\n\n\n

When did the \u201cgreenhouse signal\u201d become recognized and \u201csettled science\u201d? Despite the 35th anniversary of James Hansen\u2019s June 1988 testimony to a Senate subcommittee, the historical record should be clear that detection was not in 1988. Or 1991. Or 1995. Or 1998.<\/p>\n\n\n\n

And \u201cExxon Knew<\/a>\u201c?<\/p>\n\n\n\n

\u2014\u2014\u2014\u2014\u2014\u2014\u2014\u2014-<\/p>\n\n\n\n

Here is some history from the used-to-be newspaper of record, the New York Times<\/em>, and its global warming scribe, William K. Stevens.<\/p>\n\n\n\n

In early 1991, Stevens reported<\/a> that scientists were not ready to pronounce evidence of man-made global warming: <\/p>\n\n\n\n

\n
\n
\n

<\/p>\n<\/blockquote>\n<\/blockquote>\n\n\n\n

most scientists are far from ready to announce that greenhouse warming has arrived, since the warming recorded over the last decade could also be part of a natural climatic change. Instead, they are struggling to answer a crucial question: how can a greenhouse warming of the climate be recognized and distinguished from natural warming? They are focusing their detective efforts on various subtle changes that a greenhouse warming would be expected to induce. These signs are known collectively as the greenhouse \u201cfingerprint.\u201d<\/p>\n\n\n\n

The task, climatologists say, is by no means as easy and straightforward as it might seem. Stevens added<\/a>: <\/p>\n\n\n\n

But the greenhouse \u201csignal,\u201d if in fact it is there now, is still so small on a global scale that it is obscured by the \u201cnoise\u201d of the many other factors that influence climate. These other factors, the climatologists say, could well be the cause of the overall global warming observed in the last decade.<\/p>\n\n\n\n

Or, equally possibly, they could have produced an overall cooling that partly offset an even larger greenhouse warming than the rise in average global temperature might suggest. <\/p>\n<\/blockquote>\n\n\n\n

\u2014\u2014\u2014\u2014\u2014\u2014\u2014<\/p>\n\n\n\n

In 1995, Stevens reported that \u201cGlobal Warming Experts Call Human Role Likely.\u201d <\/a>And in 1998<\/a>:<\/p>\n\n\n\n

\n

It is clear, climatologists say, that the earth\u2019s surface has warmed since the start of the Industrial Revolution. But is the warmth out of the ordinary? And did people cause it? Scientists have been unable to provide a definitive answer to these questions because they do not know how much the global climate has varied on its own in the comparatively recent past \u2014 say, the last thousand years \u2014which offers the best basis for comparison with today\u2019s climate. Temperature records based on thermometer readings go back only about 150 years.<\/p>\n<\/blockquote>\n\n\n\n

Some scientists were saying \u2018yes,\u2019 but others no. Stevens quoted<\/a> climatologist Thomas Wigley of the National Center for Atmospheric Research in Boulder, \u201cregarded as a leading expert on the issue of detecting the greenhouse signal\u201d:<\/p>\n\n\n\n

\n

\u201dThey\u2019re making progress, and there is a lot of hard work involved, and I hold them in the highest regard,\u201d Dr. Tom Wigley, a climatologist at the National Center for Atmospheric Research in Boulder, Colo., said of Dr. Mann and his colleagues. \u201dBut I think there\u2019s a limit to how far you can ever go.\u201d As for using proxy data to detect a man-made greenhouse effect, he said, \u201dI don\u2019t think we\u2019re ever going to get to the point where we\u2019re going to be totally convincing.\u201d<\/p>\n<\/blockquote>\n\n\n\n

And \u201cExxon Knew\u201d?<\/p>\n","protected":false},"excerpt":{"rendered":"

When did the \u201cgreenhouse signal\u201d become recognized and \u201csettled science\u201d? Despite the 35th anniversary of James Hansen\u2019s June 1988 testimony to a Senate subcommittee, the historical record should be clear that detection was not in 1988. Or 1991. Or 1995. Or 1998.<\/p>\n","protected":false},"author":121246920,"featured_media":263625,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_coblocks_attr":"","_coblocks_dimensions":"","_coblocks_responsive_height":"","_coblocks_accordion_ie_support":"","_crdt_document":"","advanced_seo_description":"","jetpack_seo_html_title":"","jetpack_seo_noindex":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[1],"tags":[691818056,691818090,691820454,691820453,691818449],"class_list":{"0":"post-263622","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","6":"hentry","7":"category-uncategorized","8":"tag-climate-change","9":"tag-climate-warning","10":"tag-greenhouse-signal","11":"tag-james-hansen","12":"tag-national-center-for-atmospheric-research","14":"fallback-thumbnail"},"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/06\/0dontpanic3.webp?fit=1920%2C1357&ssl=1","jetpack_likes_enabled":true,"jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/paxLW1-16zY","jetpack-related-posts":[{"id":266959,"url":"https:\/\/climatescience.press\/?p=266959","url_meta":{"origin":263622,"position":0},"title":"Climate Fact-Check June 2023 Edition","author":"uwe.roland.gross","date":"07\/12\/2023","format":false,"excerpt":"We\u2019ll close out by returning to James Hansen\u2019s June 1988 testimony. As it turns out, June 2023 was 1.53\u00b0F\u00a0cooler\u00a0in the U.S. than June 1988.","rel":"","context":"In \"Climate change\"","block_context":{"text":"Climate change","link":"https:\/\/climatescience.press\/?tag=climate-change"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/07\/image-350.png?fit=1024%2C1024&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/07\/image-350.png?fit=1024%2C1024&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/07\/image-350.png?fit=1024%2C1024&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/07\/image-350.png?fit=1024%2C1024&ssl=1&resize=700%2C400 2x"},"classes":[]},{"id":263587,"url":"https:\/\/climatescience.press\/?p=263587","url_meta":{"origin":263622,"position":1},"title":"Wrong Again: James Hansen 1988 Senate Testimony Edition","author":"uwe.roland.gross","date":"06\/23\/2023","format":false,"excerpt":"NASA scientist James Hansen launched climate idiocy on June 23, 1988 with his famous Senate testimony. This review of it 35 years later indicates that Hansen\u2019s testimony was largely just hot air, which no doubt contributed to the legendary stuffiness of the Senate hearing room that day.","rel":"","context":"In \"Climate change\"","block_context":{"text":"Climate change","link":"https:\/\/climatescience.press\/?tag=climate-change"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/06\/0014014819_0.jpg?fit=1200%2C630&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/06\/0014014819_0.jpg?fit=1200%2C630&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/06\/0014014819_0.jpg?fit=1200%2C630&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/06\/0014014819_0.jpg?fit=1200%2C630&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/06\/0014014819_0.jpg?fit=1200%2C630&ssl=1&resize=1050%2C600 3x"},"classes":[]},{"id":205562,"url":"https:\/\/climatescience.press\/?p=205562","url_meta":{"origin":263622,"position":2},"title":"The Day the Science Died","author":"uwe.roland.gross","date":"06\/23\/2022","format":false,"excerpt":"NASA\u2019s James Hansen started the global warming scare before Congress on June 23, 1988. It was the hottest June 23 on record, and was an outlier from the eighty year cooling trend. \u201cOn Thursday (June 23, 1988) Hansen became the first climatologist to declare publicly that a major culprit in\u2026","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/06\/0June-23-Average-Maximum-Temperature-Vs-Year-1895-2022-At-All-US-Historical-Climatology-Network-Stations-Red-Line-Is-10-Year-Mean.png?fit=1200%2C1158&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/06\/0June-23-Average-Maximum-Temperature-Vs-Year-1895-2022-At-All-US-Historical-Climatology-Network-Stations-Red-Line-Is-10-Year-Mean.png?fit=1200%2C1158&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/06\/0June-23-Average-Maximum-Temperature-Vs-Year-1895-2022-At-All-US-Historical-Climatology-Network-Stations-Red-Line-Is-10-Year-Mean.png?fit=1200%2C1158&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/06\/0June-23-Average-Maximum-Temperature-Vs-Year-1895-2022-At-All-US-Historical-Climatology-Network-Stations-Red-Line-Is-10-Year-Mean.png?fit=1200%2C1158&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/06\/0June-23-Average-Maximum-Temperature-Vs-Year-1895-2022-At-All-US-Historical-Climatology-Network-Stations-Red-Line-Is-10-Year-Mean.png?fit=1200%2C1158&ssl=1&resize=1050%2C600 3x"},"classes":[]},{"id":400895,"url":"https:\/\/climatescience.press\/?p=400895","url_meta":{"origin":263622,"position":3},"title":"New York Times on Climate: Now (2025) and Then (1988)","author":"uwe.roland.gross","date":"09\/08\/2025","format":false,"excerpt":"The\u00a0New York Times\u00a0is the newspaper of record on climate alarm. 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Particularly important is the estimated anthropogenic warming and sea level rise: 3-9 degrees F and 1-4 feet between 2025 and 2050. Today, 35 years later, the recorded\u2026","rel":"","context":"In \"Climate change\"","block_context":{"text":"Climate change","link":"https:\/\/climatescience.press\/?tag=climate-change"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/06\/01355266.webp?fit=1200%2C675&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/06\/01355266.webp?fit=1200%2C675&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/06\/01355266.webp?fit=1200%2C675&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/06\/01355266.webp?fit=1200%2C675&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/06\/01355266.webp?fit=1200%2C675&ssl=1&resize=1050%2C600 3x"},"classes":[]},{"id":205286,"url":"https:\/\/climatescience.press\/?p=205286","url_meta":{"origin":263622,"position":5},"title":"Toasted Climate","author":"uwe.roland.gross","date":"06\/21\/2022","format":false,"excerpt":"\u201cWe\u2019re toast if we don\u2019t get on a very different path,\u201d Hansen, director of the Goddard Institute of Space Sciences who is sometimes called the godfather of global warming science, told The Associated Press. \u201cThis is the last chance.\u201d\u2013 JUNE 24, 2008 NASA Climate Scientist Says \u201cWe\u2019re Toast\u201d \u2013 CBS\u2026","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/06\/0Image-3605.png?fit=938%2C619&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/06\/0Image-3605.png?fit=938%2C619&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/06\/0Image-3605.png?fit=938%2C619&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/06\/0Image-3605.png?fit=938%2C619&ssl=1&resize=700%2C400 2x"},"classes":[]}],"_links":{"self":[{"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/posts\/263622","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/users\/121246920"}],"replies":[{"embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=263622"}],"version-history":[{"count":3,"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/posts\/263622\/revisions"}],"predecessor-version":[{"id":263626,"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/posts\/263622\/revisions\/263626"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/media\/263625"}],"wp:attachment":[{"href":"https:\/\/climatescience.press\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=263622"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=263622"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=263622"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}