{"id":399796,"date":"2025-09-03T19:05:00","date_gmt":"2025-09-03T17:05:00","guid":{"rendered":"https:\/\/climatescience.press\/?p=399796"},"modified":"2025-09-03T19:05:02","modified_gmt":"2025-09-03T17:05:02","slug":"new-lab-research-shows-increasing-co2-leads-to-a-negative-greenhouse-effect-at-the-poles","status":"publish","type":"post","link":"https:\/\/climatescience.press\/?p=399796","title":{"rendered":"New Lab Research Shows Increasing CO2 Leads To A Negative Greenhouse Effect At The Poles"},"content":{"rendered":"\n
\"Stylized<\/figure>\n\n\n\n

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

From NoTrickZone<\/a><\/p>\n\n\n\n

By\u00a0Kenneth Richard<\/a><\/em><\/p>\n\n\n\n

\"A<\/figure>\n\n\n\n

The evidence keeps piling up. Climate sensitivity to an increase in atmospheric CO2 is effectively zero.<\/strong><\/h4>\n\n\n\n

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

Scientists Hermann Harde and Michael Schnell published a paper in 2021 entitled \u201cVerification of the Greenhouse Effect in the Laboratory<\/a><\/strong>.\u201d The study alleged to experimentally determine the atmospheric CO2 greenhouse effect not only exists, but functions in concert with physical laws.<\/p>\n\n\n\n

\u201cTo our knowledge we present the first demonstration of the atmospheric greenhouse effect in a laboratory experiment, which also allows quantitative measurements under conditions as in the lower troposphere. We use an experimental set-up consisting of two plates in a closed housing, one plate in the upper position heated to 30\u00b0C, the other at the bottom and cooled to -11.4\u00b0C.\u201d<\/em><\/p>\n\n\n\n

A few years later Thorstein Seim and Borgar Olsen (2023<\/a><\/strong>) analyzed their experimental setup in further detail. They noted that when the CO2 is increased 500-fold, or from 0.04% (400 ppm) to 20% (200,000 ppm) in the Harde and Schnell greenhouse effect experiment the plate temperature increases by just 1.18\u00b0C, and by just 0.4\u00b0C more (1.6\u00b0C total) when the CO2 concentration reaches 100%.<\/p>\n\n\n\n

\"A
Image Source:\u00a0Seim and Olsen, 2023<\/a><\/strong><\/figcaption><\/figure>\n\n\n\n

But in their 2023 paper Seim and Olsen modified the Harde and Schnell (2021) experiment to better simulate \u201cthe earth\/atmosphere situation.\u201d They found that instead of modestly increasing the plate temperature by a little more than one degree, their tweaked experimental setup showed increasing CO2 from 0.04% to 100% actually cools<\/em> the blackbody (plate) by about -0.2 to -0.3\u00b0C.<\/p>\n\n\n\n

And now, in another new lab study, Harde and Schnell, 2025<\/a><\/strong> provide experimental evidence that further supports this negative (or near-zero) greenhouse effect at high CO2 concentrations. Their experimental setup shows increasing CO2 from 20,000 (2%) to 80,000 ppm (8%) leads to a negative greenhouse effect, resulting in tenths-of-a-degree cooling.<\/p>\n\n\n\n

This may be the second experiment to illustrate the negative greenhouse effect in a lab. Radiation studies published by other authors (Schmith\u00fcsen et al., 2015<\/a><\/strong>, Chen et al., 2024<\/a><\/strong>) also indicate the cooling influence from adding CO2 may occur in polar climates (Antarctica, Arctic). A CO2-induced high-latitude negative greenhouse effect fully undermines the anthropogenic global warming (AGW) narrative that says humans are driving \u201cpolar amplification,\u201d or rapidly melting glaciers, ice sheets, and sea ice.<\/p>\n\n\n\n

\u201cCO2 radiation is measured for three standard concentrations of 2, 4, and 8%. Addition of CO2 leads to a significant cooling of the gas temperatures\u2026\u201d<\/em><\/p>\n\n\n\n

The latest Harde and Schnell study also affirms water vapor (WV) dominates the greenhouse effect (GHE), and thus the assumption that CO2 is a driver of greenhouse effect forcing has \u201csignificant limitations.\u201d Unlike the 2, 4, and 8% CO2 volumes utilized in this experiment, the real-world atmosphere, with 0.042% CO2, is overwhelmed by WV concentrations that are 30-40 times greater. Thus, the saturated absorption bands where CO2 could potentially have an effect are \u201coverlaid\u201d or \u201coverlapped.\u201d<\/p>\n\n\n\n

\u201c[D]ue to the long propagation paths in the atmosphere and the 30-40 times higher WV concentration, the weak overlap of the spectra leads to a significant limitation of the CO2 climate sensitivity\u2026\u201d<\/em><\/p>\n\n\n\n

\u201cAs the H2O concentration increases, the gas radiation of the other GH-gases is overlaid, and their effectiveness is correspondingly reduced.\u201d<\/em><\/p>\n\n\n\n

\"Diagram
Image Source: Harde and Schnell, 2025<\/figcaption><\/figure>\n\n\n\n

It is assumed that the 100 ppm (0.01%) atmospheric CO2 increase since 1950 \u2013 from ~320 to 420 ppm \u2013 has been the primary cause of 1950-to-present global warming. However, these experiments show increasing CO2 2500-fold (0.04% to 100%) or even 100-fold (~40,000 ppm) leads to insignificant warming or even tenths-of-a-degree cooling. This tiny thermal impact is too insignificant to measurably affect Earth\u2019s climate.<\/p>\n\n\n\n

\"Graph<\/figure>\n\n\n\n

<\/p>\n","protected":false},"excerpt":{"rendered":"

The evidence keeps piling up. Climate sensitivity to an increase in atmospheric CO2 is effectively zero.<\/p>\n","protected":false},"author":121246920,"featured_media":301740,"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":"Explore how recent studies show increasing CO2 levels may lead to a negative greenhouse effect, challenging common climate narratives.","jetpack_seo_html_title":"New Research Reveals CO2's Surprisingly Minimal Climate Impact","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":false,"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":[691829997,691818087,691818296,691837682,691826963,691822277],"class_list":{"0":"post-399796","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","6":"hentry","7":"category-uncategorized","8":"tag-carbon-dioxide-co","9":"tag-global-warming","10":"tag-greenhouse-effect","11":"tag-infrared-ir-radiation","12":"tag-methane-ch4","13":"tag-water-vapor-wv","15":"fallback-thumbnail"},"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/02\/0-CO2.jpeg?fit=1600%2C1200&ssl=1","jetpack_likes_enabled":true,"jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/paxLW1-1G0k","jetpack-related-posts":[{"id":296030,"url":"https:\/\/climatescience.press\/?p=296030","url_meta":{"origin":399796,"position":0},"title":"New 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November 2023 Variations in the greenhouse effect are predominantly modulated by water vapor and cloud cover. CO2\u2019s role in the greenhouse effect is so minor it cannot be discerned. For decades scientists have reported that a CO2 concentration of about 300 ppm can only increase the\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\/11\/00image-580-1024x640-2.webp?fit=1024%2C640&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/11\/00image-580-1024x640-2.webp?fit=1024%2C640&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/11\/00image-580-1024x640-2.webp?fit=1024%2C640&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/11\/00image-580-1024x640-2.webp?fit=1024%2C640&ssl=1&resize=700%2C400 2x"},"classes":[]},{"id":252370,"url":"https:\/\/climatescience.press\/?p=252370","url_meta":{"origin":399796,"position":3},"title":"Earth\u2019s Greenhouse Effect Has Not Been Enhanced, But Instead Its Impact Has Declined Since 1983","author":"uwe.roland.gross","date":"11\/04\/2023","format":false,"excerpt":"This rules out both CO2 and an enhanced greenhouse effect as drivers of global warming.","rel":"","context":"In \"Climate warning\"","block_context":{"text":"Climate warning","link":"https:\/\/climatescience.press\/?tag=climate-warning"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/04\/00000064199.jpg?fit=1200%2C797&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/04\/00000064199.jpg?fit=1200%2C797&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/04\/00000064199.jpg?fit=1200%2C797&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/04\/00000064199.jpg?fit=1200%2C797&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/04\/00000064199.jpg?fit=1200%2C797&ssl=1&resize=1050%2C600 3x"},"classes":[]},{"id":278460,"url":"https:\/\/climatescience.press\/?p=278460","url_meta":{"origin":399796,"position":4},"title":"Lab Experiment Shows A 2500-Fold CO2 Increase Delivers Surface Cooling, Not Warming","author":"uwe.roland.gross","date":"12\/09\/2023","format":false,"excerpt":"\u201cIn\u00a0a modified experiment, where IR emission from the heating source is present, no heating but a slight cooling of a black object is found when air is replaced by CO2.\u00a0The modified experimental situation is also more like the earth\/atmosphere situation.\u201d\u00a0 \u2013\u00a0Seim and Olsen, 2023","rel":"","context":"In \"CO2\"","block_context":{"text":"CO2","link":"https:\/\/climatescience.press\/?tag=co2"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/09\/0Re-radiation_UGC_SystemModel-1.jpg?fit=1200%2C900&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/09\/0Re-radiation_UGC_SystemModel-1.jpg?fit=1200%2C900&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/09\/0Re-radiation_UGC_SystemModel-1.jpg?fit=1200%2C900&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/09\/0Re-radiation_UGC_SystemModel-1.jpg?fit=1200%2C900&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/09\/0Re-radiation_UGC_SystemModel-1.jpg?fit=1200%2C900&ssl=1&resize=1050%2C600 3x"},"classes":[]},{"id":212516,"url":"https:\/\/climatescience.press\/?p=212516","url_meta":{"origin":399796,"position":5},"title":"Scientists: The Global Warming Since 1985 Cannot Be Attributed to CO2 Forcing","author":"uwe.roland.gross","date":"08\/08\/2022","format":false,"excerpt":"Cloud modulation of shortwave radiation and greenhouse effect forcing has largely been the determining factor in the global warming of the last 45 years. 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CO2 forcing and its effect on surface temperatures is detailed in analyses of changes in clear-sky radiation only because all-sky radiation effects that include\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\/08\/0100-percent-of-outgoing-longwave-variation-1985-1998-due-to-clouds-Cess-Wang-2002.jpg?fit=1200%2C762&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/08\/0100-percent-of-outgoing-longwave-variation-1985-1998-due-to-clouds-Cess-Wang-2002.jpg?fit=1200%2C762&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/08\/0100-percent-of-outgoing-longwave-variation-1985-1998-due-to-clouds-Cess-Wang-2002.jpg?fit=1200%2C762&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/08\/0100-percent-of-outgoing-longwave-variation-1985-1998-due-to-clouds-Cess-Wang-2002.jpg?fit=1200%2C762&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/08\/0100-percent-of-outgoing-longwave-variation-1985-1998-due-to-clouds-Cess-Wang-2002.jpg?fit=1200%2C762&ssl=1&resize=1050%2C600 3x"},"classes":[]}],"_links":{"self":[{"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/posts\/399796","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=399796"}],"version-history":[{"count":6,"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/posts\/399796\/revisions"}],"predecessor-version":[{"id":399805,"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/posts\/399796\/revisions\/399805"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/media\/301740"}],"wp:attachment":[{"href":"https:\/\/climatescience.press\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=399796"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=399796"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=399796"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}