{"id":413628,"date":"2025-11-17T17:23:19","date_gmt":"2025-11-17T16:23:19","guid":{"rendered":"https:\/\/climatescience.press\/?p=413628"},"modified":"2025-11-17T17:23:21","modified_gmt":"2025-11-17T16:23:21","slug":"new-study-suggests-ice-cores-are-wrong-co2-levels-were-high-in-early-holocene","status":"publish","type":"post","link":"https:\/\/climatescience.press\/?p=413628","title":{"rendered":"New Study Suggests Ice Cores Are Wrong\u2026. CO2 Levels Were High in Early Holocene"},"content":{"rendered":"\n
\"Topographical<\/figure>\n\n\n\n

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

From No Trick Zone<\/a><\/p>\n\n\n\n

By\u00a0P Gosselin<\/a>\u00a0<\/em><\/p>\n\n\n\n

New study: CO2 levels at least equivalent to today\u2019s level of approximately 420 ppm would have been necessary 10,000 years ago.<\/strong><\/p>\n\n\n\n

Germany\u2019s online Report24 posted an article titled: \u201cWhy Ice Cores Lie: High CO2 Levels Characterized Early Times<\/a>\u201c.<\/p>\n\n\n\n

The article summarizes the study by Frans J. Schrijver titled \u201cHistorical CO2 Levels in periods of global Greening<\/em>\u201d which NTZ\u2019s author Kenneth Richard posted here<\/a>.<\/p>\n\n\n\n

\"Document<\/figure>\n\n\n\n

The Report24 article<\/a> questions the traditional measurements of CO2 values from ice cores, which suggest levels of about 280 ppm (parts per million) for the early Holocene (10,000 years ago).<\/p>\n\n\n\n

The recent study by Schrijver argues that the Earth was significantly greener 10,000 years ago, with a forest area over 50 percent higher than today. To enable such growth, CO2 levels at least equivalent to today\u2019s level of approximately 420 ppm would have been necessary. This is justified using the Mitscherlich Law, which describes the relationship between CO2  fertilization and plant growth.<\/p>\n\n\n\n

It is claimed that the Earth itself has quadrupled its natural CO2 emissions since 1750 (from 166 to 210 gigatonnes of carbon per year). In comparison, the human contribution is said to be tiny, increasing from 0 to 11 gigatonnes.<\/p>\n\n\n\n

The article concludes that the idea of low historical CO2 levels and a dramatic, human-caused increase is untenable. The Earth was already green in early times and CO2 levels were high, with practically no human influence.<\/p>\n\n\n\n

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

New study: CO2\u00a0levels at least equivalent to today\u2019s level of approximately 420 ppm would have been necessary 10,000 years ago.<\/p>\n","protected":false},"author":121246920,"featured_media":413632,"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 the new study revealing historical CO2 levels were as high as today 10,000 years ago, challenging traditional ice core data.","jetpack_seo_html_title":"High Historical CO2 Levels: A New Perspective on Earth's Greenery","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":true,"token":"eyJpbWciOiJodHRwczpcL1wvY2xpbWF0ZS1zY2llbmNlLnByZXNzXC93cC1jb250ZW50XC91cGxvYWRzXC8yMDI1XC8xMVwvMEFRT3UySHh6NDFwZ0JqTHpoLU1kaVhRMFAwZS1BS0ZwMkNvMFRydk1DMkVHZ21kS21KdVl0WVlzTm55UGVCTjdIQWxHNVJFeWhtMkc4Y2ozcXliMlZuQjNxZFRZbjI2b0NZeHpWSk1rb1htMEpqSHZLNUg5MTdRaklVSnViRlNwLTEtMTAyNHg1NjcuanBlZyIsInR4dCI6Ik5ldyBTdHVkeSBTdWdnZXN0cyBJY2UgQ29yZXMgQXJlIFdyb25nXHUyMDI2LiBDTzIgTGV2ZWxzIFdlcmUgSGlnaCBpbiBFYXJseSBIb2xvY2VuZSIsInRlbXBsYXRlIjoiaGlnaHdheSIsImZvbnQiOiIiLCJibG9nX2lkIjoxNTU4MTI0NDl9.ZPHPRiXYWT35jcxfzCvZOFqDJVvUT3KZzj_L9BVVt9gMQ"},"version":2},"jetpack_post_was_ever_published":false},"categories":[1],"tags":[691829997,691820981,691822252,691818192,691824528],"class_list":{"0":"post-413628","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-co2-fertilization-2","10":"tag-global-greening","11":"tag-holocene","12":"tag-ice-cores","14":"fallback-thumbnail"},"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2025\/11\/0AQOu2Hxz41pgBjLzh-MdiXQ0P0e-AKFp2Co0TrvMC2EGgmdKmJuYtYYsNnyPeBN7HAlG5REyhm2G8cj3qyb2VnB3qdTYn26oCYxzVJMkoXm0JjHvK5H917QjIUJubFSp-1.jpeg?fit=1768%2C979&ssl=1","jetpack_likes_enabled":true,"jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/paxLW1-1JBq","jetpack-related-posts":[{"id":170711,"url":"https:\/\/climatescience.press\/?p=170711","url_meta":{"origin":413628,"position":0},"title":"Holocene CO2 Variability and Underlying Trends","author":"uwe.roland.gross","date":"01\/11\/2021","format":false,"excerpt":"Guest Post by Renee Hannon Introduction This post compares CO2\u00a0data from Antarctic ice cores during the Holocene interglacial period with other publicly available CO2\u00a0datasets. Antarctic ice CO2\u00a0is regarded as the gold standard for paleo-atmospheric global CO2\u00a0during past interglacial and glacial periods. 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